Antibiotic Susceptibility Patterns of Bacterial Isolates from Pus Samples in a Tertiary Care Hospital of Punjab, India.

PubMed

Trojan, Rugira; Razdan, Lovely; Singh, Nasib

2016-01-01

We determined the prevalence and antibiotic susceptibilities patterns of bacterial isolates from pus samples collected from patients in a tertiary care hospital of Punjab, India. E. coli was the most prevalent pathogen (51.2%) followed by Staphylococcus aureus (21%), Klebsiella pneumoniae (11.6%), Pseudomonas aeruginosa (5.8%), Citrobacte r spp. (3.5%), Acinetobacter baumannii (2.3%), Proteus mirabilis (2.3%), and Streptococcus spp. (2.3%). E. coli , K. pneumoniae , A. baumannii , and Citrobacter isolates were resistant to multiple antibiotics including higher generation cephalosporins. S. aureus and Streptococcus isolates were sensitive to cloxacillin and vancomycin. However, P. aeruginosa , P. mirabilis , and Streptococcus isolates were found to be less resistant to the spectrum of antibiotics tested. Overall, our findings indicate the prevalence of resistance to different classes of antibiotics in bacterial isolates from pus infections and hence highlight the need for effective surveillance, regulator reporting, and antibiogram-guided antibiotic prescription.

Investigation of environmental drivers of antimicrobial resistance in foodborne bacterial pathogens in antibiotic-free, all natural, pastured poultry flocks.

USDA-ARS?s Scientific Manuscript database

Question: In the absence of antibiotic use within pastured poultry production, what are potential environmental variables that drive the antimicrobial sensitivity patterns of bacterial foodborne pathogens isolated from these flocks? Purpose: The objective of this study is to examine environmental f...

Antibiotic sensitivity pattern of bacteria from diabetic foot infections Haji Adam Malik central general hospital

NASA Astrophysics Data System (ADS)

Bulolo, B. A.; Pase, M. A.; Ginting, F.

2018-03-01

Increasing rate of Diabetic Foot Infections (DFIs) caused by multi-drug-resistance pathogens plays a huge role in the duration of hospitalization, morbidity, and mortality of diabetic patients. The aim of the study is to assess the antibiotic sensitivity pattern of bacteria in DFIs and causative microorganisms. Using cross-sectional retrospective study, data were collected from medical records of DFIs patients previously hospitalized atHaji Adam Malik Hospital, Medan from January to July 2017. 33 patients met the criteria and got enrolled in the study. The classification of DFIs was evaluated according to Wagner’s Classification. Evaluation of antibiotic sensitivity and identification of causative microorganisms were performed in standard microbiologic methods. The most common grade of DFIs was Grade-4 (48.5%), followed by Grade-3 (39.4%) and Grade-5 (9.1%). A total of 12 pathogens were identified. The most common infecting microorganism isolated on pus cultures was Klebsiella pneumonia (33.3%), followed by Escherichia coli (24.2%), Acinetobacter baumanni (12.1%), and Staphylococcus aureus (9.1%). Frequent susceptible antibiotics were Amikacin (88.8%), Imipenem (87%), Meropenem (84.6%), Erythromycin (75%), and Cefoperazone/Sulbactam (68.9%). DFIs are polymicrobial infections in this study K. pneumonia was the most common cause microorganism.

Epidemiology of bacterial isolates among pediatric cancer patients from a tertiary care oncology center in North India.

PubMed

Kapoor, G; Sachdeva, N; Jain, S

2014-01-01

Infections are a major cause of morbidity and mortality in pediatric oncology. Resistance pattern of bacterial isolates determine empiric antibiotic therapy and influence outcome. This study was planned to determine profile of bacterial isolates and their antibiotic resistance pattern among pediatric cancer patients. It was a retrospective, single institutional study. The study was carried out in the department of pediatric hematology-oncology of a tertiary care cancer centre in north India over a period of 24 months (2012-2014). Microbiological data pertaining to pediatric cancer patients, less than 18 yrs of age was analysed. Hence, 238 bacterial isolates were cultured from among 1757 blood, urine and other specimens. Gram negative bacteria were the most common (74%) pathogens identified and E. coli and Klebsiella comprised 80% of them. A high incidence of extended spectrum beta lactamase producing organisms (84%), beta-lactam beta-lactamase inhibitor (78%) and carbapenem resistance was observed (29%). Blood stream infection with multi-drug resistant Klebsiella was associated with high mortality. The gram positive bacteria isolated were predominantly staphylococcus aureus and were antibiotic sensitive. Reduction in the number of culture positive isolates in the second year of our study was probably due to rigorous implementation of infection control measures. These results on microbiologic profile and antibiotic sensitivity pattern of the isolates will be extremely helpful in revision of antibiotic guidelines for our patients and in developing strategies for coping with high prevalence of multi-drug resistance. Antibiotic stewardship and strict implementation of infection control practices will be important components of this effort.

Current trends of microorganisms and their sensitivity pattern in paediatric septic arthritis: A prospective study from tertiary care level hospital.

PubMed

Motwani, Girish; Mehta, Rujuta; Aroojis, Alaric; Vaidya, Sandeep

2017-01-01

Early treatment of septic arthritis is essential before irreversible damage to the articular cartilage occurs. Clinicians often start empirical antibiotic therapy for symptomatic relief while awaiting a definitive culture report. In present day parlance with variations in different centres in the private and public sector and rampant antibiotic abuse, a lot of resistance is being seen in the flora and their sensitivity patterns. Hence it is imperative to document and analyze these changing trends. The authors conducted a retrospective analysis of prospectively gathered data of 60 patients under 14 years of age. Joint arthrotomy was performed as a standard therapeutic protocol and the drained pus or synovial fluid was sent for gram stain and culture by 2 different methods: conventional agar plate method and BACTEC Peds Plus/F bottle method. Antibiotic susceptibility tests were done by the disc diffusion method of Clinical Laboratory Standards Institute (CLSI). The commonest presenting age group was below 1 year (80% patients) including 24 neonates. There were 19 hospital and 41 community acquired cases of septic arthritis. The hip (56%) was the commonest affected joint followed by knee (28%), shoulder joint (11%) and elbow (5%). Microorganism was isolated in 53% isolates of joint fluid only (36 culture positive patients). Conventional agar methods of culture showed positive report in only 42% patients (15/36 patients) while with the BACTEC method the yield was 71%. In the Community acquired septic arthritis, methicillin sensitive Staphylococcus aureus was isolated as commonest microbe while resistant variety of gram negative bacilli including E. coli and Klebsiella were found as predominant organism causing hospital acquired nosocomial infection of joints. The results strikingly differ in terms of response to treatment as most patients (11/19 patients) showed significant resistance to the most commonly practiced empirical antibiotic regimen of ampicillin-cloxacillin group in routine practice. When cefazolin was used as empirical antibiotic, it has shown good response and better sensitivity in 82% patients (27/33 patients). S. aureus is still the most common organism in septic arthritis. The BACTEC system was found to improve the yield of clinically significant isolates. Though a significant resistance to common antibiotic regimen is noticed, the strain is susceptible to cephalosporin group of antibiotics. We recommend the use of cephalosporine antibiotics as an empirical therapy till culture and sensitivity report are available.

Microbial aetiology and sensitivity of asymptomatic bacteriuria among ante-natal mothers in Mulago hospital, Uganda.

PubMed

Andabati, G; Byamugisha, J

2010-12-01

Asymptomatic bacteriuria in pregnancy is associated with potential urinary and obstetric complications. However the prevalence aetiology and antimicrobial sensitivity patterns of asymptomatic bacteriurea among women attending ante-natal care in our Hospital is not known. To determine the prevalence and identify the aetiological agents associated with asymptomatic bacteriurea in antenatal mothers in Mulago Hospital. We also intended to determine the anti-microbial sensitivity patterns of the common uropathogen in this population We performed culture and anti-microbial sensitivity tests on urine samples from 218 consecutive ante-natal mothers in Mulago Hospital. All participants did not have any clinical symptoms attributable to urinary tract infection. Twenty nine (13.3%) of the samples had significant bacterial growth and E.coli was the commonest isolate (51.2%). There was a high level (20-62%) of anti-bacterial resistance to the commonly used antibiotics. Asymptomatic bacteriuria is common among ante-natal mothers in Mulago. E. Coli that is resistant to the most commonly used antibiotics is the commonest isolate."

Nosocomial pneumonia: Search for an empiric and effective antibiotic regimen in high burden tertiary care centre.

PubMed

Gupta, Nitin; Soneja, Manish; Ray, Yogiraj; Sahu, Monalisa; Vinod, Kutty Sharada; Kapil, Arti; Biswas, Ashutosh; Wig, Naveet; Sood, Rita

2018-05-13

The clinical practice guidelines on nosocomial pneumonia recommends an empirical regimen that would work in 95% of the patients based on the local antibiogram. The aim of the study was development of an antibiogram for guiding empiric therapy in settings with high prevalence of multi-drug resistant organisms. A retrospective review of electronic health records (e-hospital portal) was done to analyze all respiratory isolates from patients admitted in medical wards and intensive care unit between May 2016 and May 2017. The samples included brocho-alveolar lavage (BAL), mini broncho-alveolar lavage (mini-BAL) and endotracheal aspirate. The sensitivity pattern (combined and individual) of all bacterial isolates were analysed for commonly used antibiotics and their combinations. Out of the 269 isolates, the most common organisms were Pseudomonas aeruginosa (125, 46%), Acinetobacter baumanni (74, 27%) and Klebsiella pneumoniae (50, 19%). Cefoperazone-sulbactam (43%) had the best sensitivity pattern overall. Cefoperazone-sulbactam plus amikacin (56%) was the combination with the best combined sensitivity overall. There is a high prevalence of resistance in the commonly implicated organisms to the available antibiotics. There is an urgent need for implementation of effective anti-microbial stewardship programmes and development of newer antimicrobials.

Antimicrobial resistance pattern in a tertiary care hospital: An observational study

PubMed Central

Saravanan, Revathy; Raveendaran, Vinod

2013-01-01

Context: The number of organisms developing resistance to commonly used antibiotics is increasing among the various generations. The exact national scenario of antimicrobial resistance (AMR) is not known in India owing to the absence of a central monitoring agency. Aims: The aim of this study is to identify the group of organisms developing resistance, to know the classes of drugs against, which resistance has emerged and to assess the possible factors that can favor the development of AMR so that antibiotic policy can be formulated for the proper and effective use of antibiotics. Settings and Design: An observational study was conducted for a period of 1 year from August 2011 to July 2012 in a tertiary care hospital in Pondicherry. Subjects and Methods: Data regarding culture and sensitivity of the organisms isolated from different sources such as urine, blood, wound swab/pus, stool, sputum and tracheal aspirations were collected from the records of the Microbiology Department. Sample processing, identification of organisms to the genus and/or species level and antimicrobial sensitivity were carried out as per the Clinical and Laboratory Standards Institute guidelines on the 999 samples received. Results: Out of 999 samples, 125 (12.5%) showed significant growth of organisms exhibiting resistance to either single or multiple drugs. Out of 84 (67.2%) in-patients and 41 (32.8%) out-patient samples, Escherichia was the most common organism isolated with a total of 41 (32.8%), followed by Methicillin sensitive Staphylococcus aureus, 26 (20.8%), Klebsiella 25 (20%), Methicillin resistant Staphylococcus aureus 17 (13.6%), Pseudomonas 10 (8%), Proteus 2 (1.6%), 1 (0.8%) each of Citrobacter and Enterococci. Maximum resistance was observed with commonly used first line antimicrobials such as co-trimoxazole, ampicillin, amoxicillin, amoxyclav, fluoroquinolones, third generation cephalosporins and nalidixic acid. Least resistant or highly sensitive were amikacin, nitrofurantoin, gentamycin and doxycycline among the gram-negative bacteria. Macrolides, clindamycin, gentamycin, nitrofurantoin, vancomycin were the most sensitive antimicrobials against the gram-positive bacteria. Lack of knowledge on the consequences of inappropriate use of antibiotics was exhibited by 63% of subjects in our study. Conclusions: AMR was more with hospital acquired organisms and against commonly used antibiotics that are available since long period. Variation of resistance and sensitivity pattern with time and geographical location is identified. Periodic AMR monitoring and rotation of antibiotics are suggested to restrict further emergence of resistance. PMID:24808672

Antibiotic sensitivity pattern in blaNDM-1-positive and carbapenemase-producing Enterobacteriaceae

PubMed Central

Mulla, Summaiya; Charan, Jaykaran; Rajdev, Sangita

2016-01-01

Background: Some studies published in recent time revealed that many bacteria from Enterobacteriaceae group are multi-antibiotic-resistant because of the production enzymes carbapenemase particularly New Delhi metallo-beta-lactamase encoded by gene called blaNDM-1. Looking at public health importance of this issue there is a need for studies at other centers to confirm or refute published findings. Objectives: This study was designed with the aim of exploring antibiotic resistance in Enterobacteriaceae group of bacteria and also to explore gene and enzyme responsible for it. Materials and Methods: Samples of Enterobacteriaceae were collected from wards and outpatient departments. Antibiotic sensitivity was checked by an automated system (VITEK 2 COMPACT). Carbapenemase production was assessed by Modified Hodge Test. Presence of blaNDM-1 was assessed by polymerase chain reaction. Statistics: Frequency and percentage were used to describe the data. Frequency of sensitivity was compared between carbapenemase producers and noncarbapenemase producers by Fisher's exact test. Results: Forty-seven percent bacteria were found to be producing carbapenemase enzyme. These bacteria were significantly less sensitive to cefoperazone, cefepime, and amikacin. Among carbapenemase-producing organisms, 3% and 6% were resistant to tigecycline and colistin, respectively. Forty percent bacteria were found to be having blaNDM-1 gene. There was a significant difference between blaNDM-1-positive and blaNDM-1-negative for sensitivity toward cefoperazone + sulbactam, imipenem, meropenem, amikacin, tobramycine, ciprofloxacin, and levofloxacin. Conclusion: Presence of carbapenemase enzyme and blaNDM-1 gene is associated with high level of resistance in Enterobacteriaceae group of bacteria and only few antibiotics have good sensitivity for these organisms. PMID:26958516

Heterogeneity and antibiotic resistance in Propionibacterium acnes isolates and its therapeutic implications: blurring the lines between commensal and pathogenic phylotypes.

PubMed

Sadhasivam, Suresh; Sinha, Mau; Saini, Swamini; Kaur, Simar Preet; Gupta, Tanvi; Sengupta, Shiladitya; Ghosh, Shamik; Sardana, Kabir

2016-11-01

Acne vulgaris is a multifactorial skin disease associated with the colonization of Propionibacterium acnes. Antibiotics are a mainstay of treatment for acne, yet the emergence of resistance against the currently approved antibiotics is a serious concern. In this case report, a slow responder had multiple Propionibacterium acnes isolates with varied levels of sensitivity to the conventional antibiotics. The bacterial isolates obtained from acne samples collected from the patient were analyzed for phylogeny, and was found to be largely restricted to two different lineage patterns. Propionibacterium acnes phylotype IA1, which is considered to be pathogenic, displayed clindamycin sensitivity, but phylotype IB, which is associated with commensals, exhibited high clindamycin resistance. Sensitivity analysis revealed uniform resistance to macrolides, but susceptibility to tetracycline and nadifloxacin. These results implicate Propionibacterium acnes in the pathophysiology of acne vulgaris, although the lines between commensal and pathological phylotypes may be blurred. Switching the patient to a combination of minocycline and nadifloxacin resulted in a significant improvement in the clinical lesions. Such a science-driven judicious selection of antibiotics can minimize the probability of development of resistance, and might be the way forward in the treatment of acne. © 2016 Wiley Periodicals, Inc.

Bacterial Etiology and Antibiotic Resistance Profile of Community-Acquired Urinary Tract Infections in a Cameroonian City.

PubMed

Nzalie, Rolf Nyah-Tuku; Gonsu, Hortense Kamga; Koulla-Shiro, Sinata

2016-01-01

Introduction. Community-acquired urinary tract infections (CAUTIs) are usually treated empirically. Geographical variations in etiologic agents and their antibiotic sensitivity patterns are common. Knowledge of antibiotic resistance trends is important for improving evidence-based recommendations for empirical treatment of UTIs. Our aim was to determine the major bacterial etiologies of CAUTIs and their antibiotic resistance patterns in a cosmopolitan area of Cameroon for comparison with prescription practices of local physicians. Methods. We performed a cross-sectional descriptive study at two main hospitals in Yaoundé, collecting a clean-catch mid-stream urine sample from 92 patients having a clinical diagnosis of UTI. The empirical antibiotherapy was noted, and identification of bacterial species was done on CLED agar; antibiotic susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Results. A total of 55 patients had samples positive for a UTI. Ciprofloxacin and amoxicillin/clavulanic acid were the most empirically prescribed antibiotics (30.9% and 23.6%, resp.); bacterial isolates showed high prevalence of resistance to both compounds. Escherichia coli (50.9%) was the most common pathogen, followed by Klebsiella pneumoniae (16.4%). Prevalence of resistance for ciprofloxacin was higher compared to newer quinolones. Conclusions. E. coli and K. pneumoniae were the predominant bacterial etiologies; the prevalence of resistance to commonly prescribed antibiotics was high.

Bacterial pattern and antibiotic sensitivity in children and adolescents with infected atopic dermatitis

NASA Astrophysics Data System (ADS)

Samosir, C. T.; Ruslie, R. H.; Rusli, R. E.

2018-03-01

Atopic dermatitis (AD) is a pruritic and chronic inflammatory skin disease which affected approximately 20% in children. Bacterial infection is common in AD patients and correlates directly with AD severity. A cross-sectional study was conducted to evaluate the prevalence of bacterial skin infection in AD patients and its relation with severity of AD and also to study bacteria in the infected AD and its antibiotic sensitivity. Samples were 86 children and adolescents with an AD in Helvetia Community Health Center Medan from March 2016 until February 2017. Index of SCORing Atopic Dermatitis (SCORAD) was used to evaluate the severity of AD. Lesion and nonlesional skinwere swabbed to take sterile cultures. All bacteria noted and tested for antibiotic sensitivity. Datawere by using Chi-Square and Mann Whitney test with 95% CI and p-value<0.05 was considered statistically significant. Fifty-six AD patients (65.1%) were bacterial infected. There was a significant relationship between severity of AD and bacterial infection (p = 0.006). Staphylococcus aureus was the leading bacteria from all degrees of AD severity. Isolated Staphylococcus aureuswas sensitive to amoxicillin-clavulanate (93.3%), clindamycin (90%), erythromycin (90%), and gentamicin (90%), while sensitivity to tetracycline was low (20%).

Prevalence of current patterns and predictive trends of multidrug-resistant Salmonella Typhi in Sudan.

PubMed

Elshayeb, Ayman A; Ahmed, Abdelazim A; El Siddig, Marmar A; El Hussien, Adil A

2017-11-14

Enteric fever has persistence of great impact in Sudanese public health especially during rainy season when the causative agent Salmonella enterica serovar Typhi possesses pan endemic patterns in most regions of Sudan - Khartoum. The present study aims to assess the recent state of antibiotics susceptibility of Salmonella Typhi with special concern to multidrug resistance strains and predict the emergence of new resistant patterns and outbreaks. Salmonella Typhi strains were isolated and identified according to the guidelines of the International Standardization Organization and the World Health Organization. The antibiotics susceptibilities were tested using the recommendations of the Clinical Laboratories Standards Institute. Predictions of emerging resistant bacteria patterns and outbreaks in Sudan were done using logistic regression, forecasting linear equations and in silico simulations models. A total of 124 antibiotics resistant Salmonella Typhi strains categorized in 12 average groups were isolated, different patterns of resistance statistically calculated by (y = ax - b). Minimum bactericidal concentration's predication of resistance was given the exponential trend (y = n e x ) and the predictive coefficient R 2  > 0 < 1 are approximately alike. It was assumed that resistant bacteria occurred with a constant rate of antibiotic doses during the whole experimental period. Thus, the number of sensitive bacteria decreases at the same rate as resistant occur following term to the modified predictive model which solved computationally. This study assesses the prediction of multi-drug resistance among S. Typhi isolates by applying low cost materials and simple statistical methods suitable for the most frequently used antibiotics as typhoid empirical therapy. Therefore, bacterial surveillance systems should be implemented to present data on the aetiology and current antimicrobial drug resistance patterns of community-acquired agents causing outbreaks.

Host population structure and treatment frequency maintain balancing selection on drug resistance

PubMed Central

Baskerville, Edward B.; Colijn, Caroline; Hanage, William; Fraser, Christophe; Lipsitch, Marc

2017-01-01

It is a truism that antimicrobial drugs select for resistance, but explaining pathogen- and population-specific variation in patterns of resistance remains an open problem. Like other common commensals, Streptococcus pneumoniae has demonstrated persistent coexistence of drug-sensitive and drug-resistant strains. Theoretically, this outcome is unlikely. We modelled the dynamics of competing strains of S. pneumoniae to investigate the impact of transmission dynamics and treatment-induced selective pressures on the probability of stable coexistence. We find that the outcome of competition is extremely sensitive to structure in the host population, although coexistence can arise from age-assortative transmission models with age-varying rates of antibiotic use. Moreover, we find that the selective pressure from antibiotics arises not so much from the rate of antibiotic use per se but from the frequency of treatment: frequent antibiotic therapy disproportionately impacts the fitness of sensitive strains. This same phenomenon explains why serotypes with longer durations of carriage tend to be more resistant. These dynamics may apply to other potentially pathogenic, microbial commensals and highlight how population structure, which is often omitted from models, can have a large impact. PMID:28835542

Antimicrobial sensitivity patterns of cerebrospinal fluid (CSF) isolates in Namibia: implications for empirical antibiotic treatment of meningitis.

PubMed

Mengistu, Assegid; Gaeseb, Johannes; Uaaka, Gottfried; Ndjavera, Christophine; Kambyambya, Kennedy; Indongo, Lazarus; Kalemeera, Francis; Ntege, Christopher; Mabirizi, David; Joshi, Mohan P; Sagwa, Evans

2013-01-01

Bacterial meningitis is a medical emergency associated with high mortality rates. Cerebrospinal fluid (CSF) culture is the "gold standard" for diagnosis of meningitis and it is important to establish the susceptibility of the causative microorganism to rationalize treatment. The Namibia Standard Treatment Guidelines (STGs) recommends initiation of empirical antibiotic treatment in patients with signs and symptoms of meningitis after taking a CSF sample for culture and sensitivity. The objective of this study was to assess the antimicrobial sensitivity patterns of microorganisms isolated from CSF to antibiotics commonly used in the empirical treatment of suspected bacterial meningitis in Namibia. This was a cross-sectional descriptive study of routinely collected antibiotic susceptibility data from the Namibia Institute of Pathology (NIP) database. Results of CSF culture and sensitivity from January 1, 2009 to May 31, 2012, from 33 state hospitals throughout Namibia were analysed. The most common pathogens isolated were Streptococcus species, Neisseria meningitidis, Haemophilus influenzae, Staphylococcus, and Escherichia coli. The common isolates from CSF showed high resistance (34.3% -73.5%) to penicillin. Over one third (34.3%) of Streptococcus were resistance to penicillin which was higher than 24.8% resistance in the United States. Meningococci were susceptible to several antimicrobial agents including penicillin. The sensitivity to cephalosporins remained high for Streptococcus, Neisseria, E. coli and Haemophilus. The highest percentage of resistance to cephalosporins was seen among ESBL K. pneumoniae (n = 7, 71%-100%), other Klebsiella species (n = 7, 28%-80%), and Staphylococcus (n = 36, 25%-40%). The common organisms isolated from CSF were Streptococcus Pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Staphylococcus, and E. coli. All common organisms isolated from CSF showed high sensitivity to cephalosporins used in the empirical treatment of meningitis. The resistance of the common isolates to penicillin is high. Most ESBL K. pneumoniae were isolated from CSF samples drawn from neonates and were found to be resistant to the antibiotics recommended in the Namibia STGs. Based on the above findings, it is recommended to use a combination of aminoglycoside and third-generation cephalosporin to treat non-ESBL Klebsiella isolates. Carbapenems (e.g., meropenem) and piperacillin/tazobactam should be considered for treating severely ill patients with suspected ESBL Klebsiella infection. Namibia should have a national antimicrobial resistance surveillance system for early detection of antibiotics that may no longer be effective in treating meningitis and other life-threatening infections due to resistance.

Antibiotic Resistances of Yogurt Starter Cultures Streptococcus thermophilus and Lactobacillus bulgaricus

PubMed Central

Sozzi, Tommaso; Smiley, Martin B.

1980-01-01

Twenty-nine strains of Lactobacillus bulgaricus and 15 strains of Streptococcus thermophilus were tested for resistance to 35 antimicrobial agents by using commercially available sensitivity disks. Approximately 35% of the isolates had uncharacteristic resistance patterns. PMID:16345654

Breast Implant-Associated Infections: The Role of the National Surgical Quality Improvement Program and the Local Microbiome.

PubMed

Cohen, Justin B; Carroll, Cathy; Tenenbaum, Marissa M; Myckatyn, Terence M

2015-11-01

The most common cause of surgical readmission after breast implant surgery remains infection. Six causative organisms are principally involved: Staphylococcus epidermidis and S. aureus, Escherichia, Pseudomonas, Propionibacterium, and Corynebacterium. The authors investigated the infection patterns and antibiotic sensitivities to characterize their local microbiome and determine ideal antibiotic selection. A retrospective review of 2285 consecutive implant-based breast procedures was performed. Included surgical procedures were immediate and delayed breast reconstruction, tissue expander exchange, and cosmetic augmentation. Patient demographics, chemotherapy and/or irradiation status, implant characteristics, explantation reason, time to infection, microbiological data, and antibiotic sensitivities were reviewed. Forty-seven patients (2.1 percent) required inpatient admission for antibiotics, operative explantation, or drainage by interventional radiology. The infection rate varied depending on surgical procedure, with the highest rate seen in mastectomy and immediate tissue expander reconstruction (6.1 percent). The mean time to explantation was 41 days. Only 50 percent of infections occurred within 30 days of the indexed National Surgical Quality Improvement Program operation. The most commonly isolated organisms were coagulase-negative Staphylococcus (27 percent), methicillin-sensitive S. aureus (25 percent), methicillin-resistant S. aureus (7 percent), Pseudomonas (7 percent), and Peptostreptococcus (7 percent). All Gram-positive organisms were sensitive to vancomycin, linezolid, tetracycline, and doxycycline; all Gram-negative organisms were sensitive to gentamicin and cefepime. Empiric antibiotics should be vancomycin (with the possible inclusion of gentamicin) based on their broad effectiveness against the authors' unique microbiome. Minor infections should be treated with tetracycline or doxycycline as a second-line agent. National Surgical Quality Improvement Program data are adequate for monitoring and comparing breast infections but certainly not comprehensive. Therapeutic, IV.

Enteric fever in Mumbai--clinical profile, sensitivity patterns and response to antimicrobials.

PubMed

Jog, S; Soman, R; Singhal, T; Rodrigues, C; Mehta, A; Dastur, F D

2008-04-01

Enteric fever is endemic in Mumbai and its diagnosis poses several problems. Our main aim was to study the clinical profile, haematological features of culture proven typhoid cases, the antimicrobial susceptibility pattern of the isolates and the time to defervescence with the treatment received. This was a retospective chart review of all cases of culture proven enteric fever carried out at a tertiary care private hospital in Mumbai over the period January 2003 to September 2005. Culture positivity in our study was 52.6%. Sixty one percent of the isolates were Salmonella typhi while 39% were Salmonella paratyphi A. An absolute eosinopenia was seen in 76.9% of the patients. Before being admitted to the hospital, 46.2% received antibiotics. The mean time to defervescence in patients who received prior antibiotics was 4.5 days while that in those who did not receive prior antibiotics was 5.1 days. A high culture positivity despite prior or ongoing antibiotic treatment was seen. Absolute eosinophil count of 0% could be an important marker of typhoid. High prevalence of nalidixic acid resistance, a marker of resistance to fluoroquinolones was observed. Combination treatment was not found to be superior to treatment with a single antibiotic.

Antimicrobial resistance pattern and genetic correlation in Enterococcus faecium isolated from healthy volunteers.

PubMed

Asadian, M; Sadeghi, J; Rastegar Lari, A; Razavi, Sh; Hasannejad Bibalan, M; Talebi, M

2016-03-01

Enterococci are known as a cause of nosocomial infections and this aptitude is intensified by the growth of antibiotic resistance. In the present study, Enterococcus faecium isolates from healthy volunteers were considered to determine the antibiotic resistance profiles and genetic correlation. A total 91 normal flora isolates of enterococci were included in this study. Identification of Enterococcus genus and species were done by biochemical and PCR methods, respectively. Sensitivity for 10 antibiotics was determined and genetic relatedness of all isolates was assessed using Repetitive Element Palindromic PCR (REP-PCR) followed by Pulse Field Gel Electrophoresis (PFGE) on the representative patterns. None of the isolates were resistant to teicoplanin, vancomycin, quinupristin-dalfopristin, linezolid, chloramphenicol, ampicillin and high-level gentamicin. On the other hand, the resistance rate was detected in 30.7%, 23%, and 3.29% of isolates for erythromycin, tetracycline and ciprofloxacin, respectively. The results of PFGE showed 19 (61.5% of our isolates) common types (CT) and 35 (38.5%) single types (ST) amongst the isolates. This is the first study to describe antibiotic resistance pattern and genetic relationship among normal flora enterococci in Iran. This study showed no prevalence of Vancomycin Resistant Enterococci (VRE) and high degrees of diversity among normal flora isolates by genotyping using PFGE. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical Options for the Treatment of Urinary Tract Infections in Children

PubMed Central

Ramlakhan, Shammi; Singh, Virendra; Stone, Joanne; Ramtahal, Alicia

2014-01-01

Urinary Tract Infections (UTI) are a common cause of childhood febrile illness with 7% of girls and 2% of boys having a symptomatic culture positive UTI by the age of six years. Although there are conflicting views on the long term sequelae of UTI, as well as the place of prophylaxis, the universal aims of treatment of childhood UTI remain those of symptom alleviation, prevention of systemic infection and short and longer term complications. There is good evidence of historical and emerging resistance patterns, therefore rationalisation of prescription patterns by knowledge of sensitivities coupled with re-examination of empirical antibiotic choices is clearly important. Local formularies should reflect geographical resistance patterns along with best evidence on the duration and choice of antibiotic in order to maximize therapeutic effect, while minimizing the development of resistant strains. PMID:25210486

The choice of antibiotic in open fractures in a teaching hospital in a developing country.

PubMed

Alonge, T O; Salawu, S A; Adebisi, A T; Fashina, A N

2002-06-01

Open fracture wounds may be contaminated, and the use of an appropriate antibiotic in the early stages of management reduces the risk of osteomyelitis developing. Environmental factors influence both the type of micro-organisms that are isolated from these wounds and the antibiotics that are chosen to manage the wounds. Before this study, the choice of antibiotic in the management of open fractures in our hospital was based on tradition and 'best guess' antibiotics. In a prospective study of 52 open fractures seen in the accident and emergency unit of University College Hospital, Ibadan, between January and June 2000, the positive bacterial culture yield was more than 70%. Staphylococcus aureus was the commonest microbial isolate, accounting for 37.5% of total isolates. The antibiotic sensitivity pattern revealed high efficacies for pefloxacin, ciprofloxacin and ceftriaxone against the isolated micro-organisms. In comparative costs, these antibiotics are cheaper than the combination of the 'best guess' antibiotics that were used previously. On the strength of this finding, we have suggested a change in the antibiotic policy of the hospital with regard to the antibiotic regimen to be used to complement the surgical management of open fractures.

[Antibiotic resistance of streptococcus pneumoniae among healthy nasopharyngeal carriers in seven regions of Peru].

PubMed

Torres, Nancy; Velásquez, Ricardo; Mercado, Erik H; Egoavil, Martha; Horna, Gertrudis; Mejía, Lida; Castillo, María E; Chaparro, Eduardo; Hernández, Roger; Silva, Wilda; Campos, Francisco E; Sáenz, Andrés; Hidalgo, Félix; Letona, Carolina; Valencia, Angel G; Cerpa, Rosario; López-de-Romaña, Bernardo; Torres, Berenice; Castillo, Fiorella; Calle, Andrea; Rabanal, Synthia; Pando, Jackeline; Lacroix, Elizabeth; Reyes, Isabel; Guerra, Humberto; Ochoa, Theresa J

2013-01-01

To determine the pattern of antibiotic susceptibility of isolated Streptococcus pneumoniae strains of healthy nasopharyngeal carriers younger than 2 years in seven regions of Peru. Between 2007 and 2009, nasopharyngeal swab samples were collected among 2123 healthy children aged 2-24 months in growth and development medical practices (CRED) and vaccination offices of hospitals and health centers in Lima, Piura, Cusco, Abancay, Arequipa, Huancayo, and Iquitos. The resistance to ten antibiotics through disk diffusion sensitivity testing of isolated pneumococcus strains was determined. 572 strains were isolated. High rates of resistance to co-trimoxazole (58%), penicillin (52.2% non-sensitive); tetracycline (29,1%); azithromycin (28,9%), and erythromycin (26,3%). Resistance to chloramphenicol was low (8.8%). Multiresistance was found at 29.5%. Resistance to azithromycin and penicillin was different in all seven regions (p<0,05), the highest percentage of non-sensitive strains being found in Arequipa (63,6%), whereas the lowest percentage was found in Cusco (23.4%). High levels of resistance found to penicillin, co-trimoxasole and macrolides in isolated pneumococcus strains of healthy carriers in all studied regions, and their association to a previous use of antibiotics, represent a significant public health problem in our country. This emphasizes the need to implement nationwide strategies to reduce the irrational use of antibiotics, especially among children. It is necessary to complement data of resistance to penicillin with the determination of minimal inhibitory concentration to make proper therapeutic recommendations.

Bacterial Profile and Antibiotic Resistance in Patients with Diabetic Foot Ulcer in Guangzhou, Southern China: Focus on the Differences among Different Wagner's Grades, IDSA/IWGDF Grades, and Ulcer Types

PubMed Central

Xie, Xiaoying; Bao, Yunwen; Ni, Lijia; Liu, Dan; Niu, Shaona; Lin, Haixiong; Li, Hongyu; Duan, Chaohui; Yan, Li; Luo, Zhaofan

2017-01-01

Objective To understand the bacterial profile and antibiotic resistance patterns in diabetic foot infection (DFI) in different Wagner's grades, IDSA/IWGDF grades, and different ulcer types in Guangzhou, in order to provide more detailed suggestion to the clinician about the empirical antibiotic choice. Methods 207 bacteria were collected from 117 DFIs in Sun Yat-sen Memorial Hospital from Jan.1, 2010, to Dec.31, 2015. The clinical data and microbial information were analyzed. Results The proportion of Gram-negative bacteria (GNB) was higher than Gram-positive bacteria (GPB) (54.1% versus 45.9%), in which Enterobacteriaceae (73.2%) and Staphylococcus (65.2%) were predominant, respectively. With an increasing of Wagner's grades and IDSA/IWGDF grades, the proportion of GNB bacterial infection, especially Pseudomonas, was increased. Neuro-ischemic ulcer (N-IFU) was more susceptible to GNB infection. Furthermore, with the aggravation of the wound and infection, the antibiotic resistance rates were obviously increased. GPB isolated in ischemic foot ulcer (IFU) showed more resistance than the N-IFU, while GNB isolates were on the opposite. Conclusions Different bacterial profiles and antibiotic sensitivity were found in different DFU grades and types. Clinician should try to stay updated in antibiotic resistance pattern of common pathogens in their area. This paper provided them the detailed information in this region. PMID:29075293

Infants under two months of age with urinary tract infections are showing increasing resistance to empirical and oral antibiotics.

PubMed

Segal, Zvi; Cohen, Matan J; Engelhard, Dan; Tenenbaum, Ariel; Simckes, Ari M; Benenson, Shmuel; Stepensky, Polina; Averbuch, Diana

2016-04-01

Data on antimicrobial resistance in uropathogens in infants up to the age of three months are limited. This study characterised resistance patterns in Gram-negative uropathogens in infants up to the age of two months. Previously healthy young infants with urinary tract infections (UTIs) were studied retrospectively. Antimicrobial susceptibility was evaluated. Multidrug resistance (MDR) was defined as resistance to at least three antibiotic classes. Clinical, laboratory and outcome data were compared between infants with UTIs caused by bacteria sensitive and resistant to empirical and to oral therapy. We evaluated 306 UTI episodes with 314 pathogens. The following resistance rates were observed: ampicillin 73.7%, cefazoline 22.1%, ampicillin/clavulanate 21.8%, cefuroxime 7.8%, gentamicin 7%; MDR 11.8%; resistant to empirical treatment 7.3% and resistant to available oral antibiotics 8.6%. Our study showed that pathogens resistant to empirical and oral therapy were more frequently isolated in non-Jewish (Arab) infants and in those of ≥30 days of age. Resistance to empirical treatment and oral antibiotics also resulted in longer mean hospital stays. Resistance to antibiotics challenges empirical therapy and compromises oral treatment options in young infants with UTIs. Antimicrobial resistance patterns should be monitored in infants to determine appropriate empirical antibiotic therapy protocols. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Analysis of antibiotic resistance pattern of S. aureus strains isolated from the Orthopedics-Traumatology Section of "Sf. Spiridon" Clinical Emergency Hospital, Iaşi.

PubMed

Tucaliuc, D; Alexa, O; Tuchiluş, Cristina Gabriela; Ursu, Ramona Gabriela; Tucaliuc, Elena Simona; Iancu, Luminiţa Smaranda

2014-01-01

The retrospective analysis of antibiotic sensibility of S. aureus strains isolated from infected patients from the Orthopedics-Traumatology Clinic of "Sf. Spiridon" Clinical Emergency Hospital, Iaşi during January 2003-December 2013, in view of determining the evolution trend of the resistance phenomenon and of pinpointing the most useful treatment for these strains. The antibiotic sensitivity test was carried out using two methods: diffusimetric-Kirby-Bauer and the MIC determination by E-test (for the strains isolated in 2013); the interpretation of the sensitivity was made in a standardized manner, in compliance with the CLSI (Clinical and Laboratory Standards Institute) standard for antibiotics testing in force. The sensitivity testing for beta-lactams proved that during the 11 years of the study, the average value of the frequency of resistant strains was of 41.59% +/- 8.68. The highest frequency of MRSA (Methicillin Restant S. aureus) strains was noticed in 2012 (58.6%), followed by 2004 (50.7%). Even if in 2013 it dropped to 38.9%, the trend calculated for 2003-2013 is slightly rising (y = 0.0073x + 0.372). Out of the total of 495 S. aureus strains that were isolated, 164 (33.13%) were completely sensitive to the tested antibiotics and 26 (5.25%) were resistant only to beta-lactams. The other MRSA strains associated multiple resistance and MIC for vancomycin varied between 0.5-2 mg/ml. Two strains whose MIC was of 0.5 mg/ml were sensitive to most classes of tested antibiotics, including beta-lactams, except for macrolides (erythromycin), and the strain whose MIC was of 2 mg/ml, was resistant to all classes of tested antibiotics, except for glycopeptides and oxazolidiones. The other tested strains had a MIC for vancomycin equal to 1 mg/ml. Due to the fact that there are infections with SAMR strains in a rather worrying percentage (53.9%) that are resistant to the other classes of antibiotics, the only therapeutic solution being the vancomycin treatment, its use should be limited solely to those cases when it is really necessary. Fortunately, no vancomycin resistant MRSA strains have been identified in our country, but this phenomenon should be kept under close surveillance.

Molecular characterization and evaluation of the emerging antibiotic-resistant Streptococcus pyogenes from eastern India.

PubMed

Ray, Dipanwita; Saha, Somnath; Sinha, Sukanta; Pal, Nishith Kumar; Bhattacharya, Basudev

2016-12-12

Group A Streptococcus strains causing wide variety of diseases, recently became noticeable in eastern India, are not amenable to standard treatment protocol thus enhancing the possibility of disease morbidity by becoming antibiotic resistance. The association of Lancefield group A Streptococcal variation with degree of vir architectural diversity was evaluated using emm typing and restriction fragment length polymorphism analyses. The antibiotic sensitivity patterns were examined by modified Kirby-Bauer method of disk diffusion. Percentage calculations, 95% confidence interval and one-way ANOVA were used to assess differences in proportions. Our observations revealed 20 different emm types and 13 different HaeIII vir typing patterns. A 1.2 kb fragment was found in all HaeIII typing pattern. Fragments of 1.2 kb and 550 bp were conserved in majority of the isolates. HinfI digestion was found proficient in differentiating the strains of same vir typing patterns. Strong predominance of speC (85%) and speF (80%) genes have been observed encoding exotoxins production. 4 isolates were found to be erythromycin resistant and were of genotype emm49. High degree of tetracycline resistance was shown by 53.57% isolates which belonged to 12 different emm genotypes. These findings suggested that in addition to emm typing, sequential application of HaeIII and HinfI restriction enzymes in vir typing analysis is an effective tool for group A streptococcal molecular characterization associated with antibiotic resistance.

Neonatal blood stream infections in tertiary referral hospitals in Kurdistan, Iran.

PubMed

Nikkhoo, Bahram; Lahurpur, Fariba; Delpisheh, Ali; Rasouli, Mohammad Aziz; Afkhamzadeh, Abdorrahim

2015-06-09

Bloodstream infection (BSI) is one of the most common causes of nosocomial infection in neonatal intensive care units (NICU). The aim of the present study was to determine bacterial agents and their susceptibility patterns to antibiotics and to investigate the risk factors associated with BSI. This was a nested case-control study carried out from September 2009 to June 2010 in the NICU wards in Sanandaj hospitals western Iran. Cases were patients with BSI and controls were other patients who had negative blood culture. Bacteriologic diagnosis and antibiotic susceptibility pattern was performed based on the Edward & Ewings and the National Committee of Clinical Laboratory (NCCL) Standards. Of 472 patients who hospitalized in NICU, 6.4% had BSI (n = 30) including 17girls (56.7%) and 13 boys (43.3%). Enterobacter SPP was the predominant isolated bacteria from blood culture (36.7%). The maximum antibiotic resistance and sensitivity were observed by Tetracycline and Ciprofloxacin respectively. Risk factors associated with BSI were age ≤ 7 days (p = 0.001), previous antibiotic consumption (p = 0.013), and low birth weight (LBW), (p = 0.001). Gram negative bacteria and Entrobacter in particular are the most common pathogens. Improving prenatal health care, standards of infection control and choosing accurate antibiotics are recommended to avoid BSI in neonatal intensive care units.

Reinventing the Wheel: Impact of Prolonged Antibiotic Exposure on Multi-Drug Resistant Ventilator-Associated Pneumonia in Trauma Patients.

PubMed

Lewis, Richard H; Sharpe, John P; Swanson, Joseph M; Fabian, Timothy C; Croce, Martin A; Magnotti, Louis J

2018-04-16

Multi-drug resistant (MDR) strains of both Acinetobacter baumannii (AB) and Pseudomonas aeruginosa (PA) as causative VAP pathogens are becoming increasingly common. Still, the risk factors associated with this increased resistance have yet to be elucidated. The purpose of this study was to examine the changing sensitivity patterns of these pathogens over time and determine which risk factors predict MDR in trauma patients with VAP. Patients with either AB or PA VAP over 10 years were stratified by pathogen sensitivity (sensitive (SEN) and MDR), age, severity of shock and injury severity. Prophylactic and empiric antibiotic days, risk factors for severe VAP and mortality were compared. Multivariable logistic regression (MLR) was performed to determine which risk factors were independent predictors of MDR. 397 patients were identified with AB or PA VAP. There were 173 episodes of AB (91 SEN and 82 MDR) and 224 episodes of PA (170 SEN and 54 MDR). The incidence of MDR VAP did not change over the study (p=0.633). Groups were clinically similar with the exception of 24-hour transfusions (14 vs 19 units, p = 0.009) and extremity AIS (1 vs 3, p<0.001), both significantly increased in the MDR group. Antibiotic exposure as well as mIEAT (63% vs 81%, p<0.001) were significantly increased in the MDR group. MLR identified prophylactic antibiotic days (OR 23.1; 95%CI 16.7-28, p<0.001) and mIEAT (OR 18.1; 95%CI 12.2-26.1, p=0.001) as independent predictors of MDR after adjusting for severity of shock, injury severity, severity of VAP and antibiotic exposure. Prolonged exposure to unnecessary antibiotics remains one of the strongest predictors for the development of antibiotic resistance. MLR identified prophylactic antibiotic days and mIEAT an independent risk factors for MDR VAP. Thus, limiting prophylactic antibiotic days is the only potentially modifiable risk factor for the development of MDR VAP in trauma patients. Level III, Prognostic LEVEL OF EVIDENCE: Multi-drug resistant, antibiotic exposure.

Study of Pre-disposing Factors of Acute Exacerbation of Chronic Obstructive Pulmonary Disease and Antibiotic Prescribing Pattern with Reference to Antibiotic Sensitivity Test.

PubMed

Shrestha, R; Shrestha, B; Shakya Shrestha, S; Pant, A; Prajapati, B; Karmacharya, B M

2015-01-01

Background Chronic Obstructive Pulmonary Disease (COPD) affects about 329 million people worldwide, which is nearly 5% of the entire global population. In the context of Nepal, COPD accounts for 43% of the non-communicable disease burden and 2.56% of hospitalizations. Various pre-disposing factors like bacterial, viral, fungal, smoking, occupational exposures and genetic factors have been proposed to precipitate COPD and its exacerbation though, the definitive pre-disposing factors and factors related to acute exacerbation have not been determined in the context of Nepal. Objective To find out the pre-disposing factors and the related causative agents for COPD. Method A cross sectional study was conducted in a tertiary care hospital. Patients of all age group who were diagnosed as COPD and admitted in the hospital were included in this study. Patients were interviewed using structured questionnaire. The sociodemographic data including personal and medical history were recorded from those participants. In addition, sputum from those patients was sent for culture to investigate the possible responsible pathogens as well as its antibiotic sensitivity pattern. Result A total of 150 patients having Acute Exacerbation of Chronic Obstructive Pulmonary Disease (AECOPD) who have admitted from either emergency or out-patient department of the hospital were included in this study. Among the total number of patients, more than half of them were female (n=82). In addition, analysis of occupations shows that most of them were either farmer (36.0%) or housewife (30.7%). In total studied patients (n=150), most of them were using traditional firewood (83%) for cooking purpose and majority of patients (91%) were smokers. Most of the sputum samples show growth of gram-positive cocci (26.7%) and gram negative bacilli (27.5%). Considering the overall sensitivity pattern, the higher sensitivity was recorded for Co-trimoxazole and Ciprofloxacin while higher rate of resistance was noted for Penicillin group of drugs. The most widely used antibiotics were found to be Cephalosporin group of drugs (68%). Conclusion The present study revealed that the case of COPD is more in female and the commonest pre-disposing factor is found to be smoke/firewood. Cephalosporin group of drugs is the most commonly prescribed drug.

The comparison of printed resources bacterial contamination in libraries of Al-Zahra Hospital and Sciences Faculty of Isfahan University and the determination of their antibiotic sensitivity pattern.

PubMed

Rafiei, Hosein; Chadeganipour, Mostafa; Ojaghi, Rezvan; Maracy, Mohammad Reza; Nouri, Rasool

2017-01-01

During the library loan process, the printed resources can be a carrier of pathogenic bacteria. In this study, it was tried to compare the Bacterial Contamination Rates and their antibiotic sensitivity pattern in printed resources of a hospital and a non-hospital library. This is a cross-sectional study. Returning books from the Al-Zahra hospital library and library of Sciences faculty of Isfahan University provides the research community. The sample size, 96 cases, was calculated using quota sampling. For sampling sterile swab dipped in trypticase soy broth medium and transfer trypticase soy broth medium were used. To identify different type of isolated bacteria from Gram-staining test and biochemical tests such as; TSI, IMViC and etc., were used. 76 (79.2%) and 20 (20.8%) of cultured samples were negative and positive, the respectively. Of 20 positive samples, 11 samples (55%) belong to the family Enterobacteriaceae that after detecting by Differential teste identified all 11 samples of Enterobacter that all of them were sensitive to Gentamicin and Ofloxacin. Also the most resistance to Nitrofurantoin and Amikacin was observed. 9 cases remained (45%) were coagulase-negative Staphylococcus that all of them were sensitive to the Trimethoprim-sulfamethoxazole and Cephalexin antibiotics also the most resistance to Cefixime was observed. Considering that the Enterobacter sp and coagulase-negative Staphylococcus were separated from the books, the books as well as other hospital and medical equipment can transmit the infection to librarians, library users, patients and hospital staff, and also it can produce serious infections in patients with immune deficiency.

The comparison of printed resources bacterial contamination in libraries of Al-Zahra Hospital and Sciences Faculty of Isfahan University and the determination of their antibiotic sensitivity pattern

PubMed Central

Rafiei, Hosein; Chadeganipour, Mostafa; Ojaghi, Rezvan; Maracy, Mohammad Reza; Nouri, Rasool

2017-01-01

Introduction: During the library loan process, the printed resources can be a carrier of pathogenic bacteria. In this study, it was tried to compare the Bacterial Contamination Rates and their antibiotic sensitivity pattern in printed resources of a hospital and a non-hospital library. Methods: This is a cross-sectional study. Returning books from the Al-Zahra hospital library and library of Sciences faculty of Isfahan University provides the research community. The sample size, 96 cases, was calculated using quota sampling. For sampling sterile swab dipped in trypticase soy broth medium and transfer trypticase soy broth medium were used. To identify different type of isolated bacteria from Gram-staining test and biochemical tests such as; TSI, IMViC and etc., were used. Results: 76 (79.2%) and 20 (20.8%) of cultured samples were negative and positive, the respectively. Of 20 positive samples, 11 samples (55%) belong to the family Enterobacteriaceae that after detecting by Differential teste identified all 11 samples of Enterobacter that all of them were sensitive to Gentamicin and Ofloxacin. Also the most resistance to Nitrofurantoin and Amikacin was observed. 9 cases remained (45%) were coagulase-negative Staphylococcus that all of them were sensitive to the Trimethoprim-sulfamethoxazole and Cephalexin antibiotics also the most resistance to Cefixime was observed. Conclusion: Considering that the Enterobacter sp and coagulase-negative Staphylococcus were separated from the books, the books as well as other hospital and medical equipment can transmit the infection to librarians, library users, patients and hospital staff, and also it can produce serious infections in patients with immune deficiency. PMID:28546984

Temperate and lytic bacteriophages programmed to sensitize and kill antibiotic-resistant bacteria

PubMed Central

Yosef, Ido; Manor, Miriam; Kiro, Ruth

2015-01-01

The increasing threat of pathogen resistance to antibiotics requires the development of novel antimicrobial strategies. Here we present a proof of concept for a genetic strategy that aims to sensitize bacteria to antibiotics and selectively kill antibiotic-resistant bacteria. We use temperate phages to deliver a functional clustered regularly interspaced short palindromic repeats (CRISPR)–CRISPR-associated (Cas) system into the genome of antibiotic-resistant bacteria. The delivered CRISPR-Cas system destroys both antibiotic resistance-conferring plasmids and genetically modified lytic phages. This linkage between antibiotic sensitization and protection from lytic phages is a key feature of the strategy. It allows programming of lytic phages to kill only antibiotic-resistant bacteria while protecting antibiotic-sensitized bacteria. Phages designed according to this strategy may be used on hospital surfaces and hand sanitizers to facilitate replacement of antibiotic-resistant pathogens with sensitive ones. PMID:26060300

Temperate and lytic bacteriophages programmed to sensitize and kill antibiotic-resistant bacteria.

PubMed

Yosef, Ido; Manor, Miriam; Kiro, Ruth; Qimron, Udi

2015-06-09

The increasing threat of pathogen resistance to antibiotics requires the development of novel antimicrobial strategies. Here we present a proof of concept for a genetic strategy that aims to sensitize bacteria to antibiotics and selectively kill antibiotic-resistant bacteria. We use temperate phages to deliver a functional clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) system into the genome of antibiotic-resistant bacteria. The delivered CRISPR-Cas system destroys both antibiotic resistance-conferring plasmids and genetically modified lytic phages. This linkage between antibiotic sensitization and protection from lytic phages is a key feature of the strategy. It allows programming of lytic phages to kill only antibiotic-resistant bacteria while protecting antibiotic-sensitized bacteria. Phages designed according to this strategy may be used on hospital surfaces and hand sanitizers to facilitate replacement of antibiotic-resistant pathogens with sensitive ones.

Antibiotic therapy for Shigella dysentery.

PubMed

Prince Christopher R H; David, Kirubah V; John, Sushil M; Sankarapandian, Venkatesan

2010-01-20

Shigella dysentery is a relatively common illness and occasionally causes death, worldwide. Mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. The antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects. To evaluate the efficacy and safety of antibiotics for treating Shigella dysentery. In June 2009 we identified all relevant trials from the following databases: Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, issue 4), MEDLINE, EMBASE, LILACS and the metaRegister of Controlled Trials (mRCT). We also checked conference proceedings for relevant abstracts, and contacted researchers, organizations, and pharmaceutical companies. Randomized controlled trials of antibiotics for Shigella dysentery. Four authors, working in pairs, independently assessed trial eligibility, methodological quality, and extracted data. We calculated risk ratios (RR) with 95% confidence intervals (CI) for dichotomous data, and used the random-effects model for significant heterogeneity. We explored possible sources of heterogeneity, when present, in subgroup analyses of participant age and percentage of participants with confirmed Shigella infection. Sixteen trials (1748 participants), spanning four decades and with differing sensitivity to Shigella isolates, met the inclusion criteria. Seven were judged to be at risk of bias due to inadequate allocation concealment or blinding, and 12 due to incomplete reporting of outcome data. Limited data from one three-armed trial of people with moderately severe illness suggest that antibiotics reduce the episodes of diarrhoea at follow-up (furazolidone versus no drug RR 0.21, 95% CI 0.09 to 0.48, 73 participants; cotrimoxazole versus no drug RR 0.30, 95% CI 0.15 to 0.59, 76 participants).There was insufficient evidence to consider any class of antibiotic superior in efficacy in treating Shigella dysentery, but heterogeneity for some comparisons limits confidence in the results. All the antibiotics studied were safe. There was inadequate evidence regarding the role of antibiotics in preventing relapses. Antibiotics reduce the duration of Shigella dysentery.Regularly updated local or regional antibiotic sensitivity patterns to different species and strains of Shigella are required to guide empiric therapy. More trials adhering to standard guidelines are required to evaluate the role of antibiotics in the treatment of severe forms of Shigella dysentery and in groups who are at high risk of complications.

Antibiotic therapy for Shigella dysentery.

PubMed

Christopher, Prince Rh; David, Kirubah V; John, Sushil M; Sankarapandian, Venkatesan

2010-08-04

Shigella dysentery is a relatively common illness and occasionally causes death, worldwide. Mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. The antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects. To evaluate the efficacy and safety of antibiotics for treating Shigella dysentery. In June 2009 we identified all relevant trials from the following databases: Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, issue 4), MEDLINE, EMBASE, LILACS and the metaRegister of Controlled Trials (mRCT). We also checked conference proceedings for relevant abstracts, and contacted researchers, organizations, and pharmaceutical companies. Randomized controlled trials of antibiotics for Shigella dysentery. Four authors, working in pairs, independently assessed trial eligibility, methodological quality, and extracted data. We calculated risk ratios (RR) with 95% confidence intervals (CI) for dichotomous data, and used the random-effects model for significant heterogeneity. We explored possible sources of heterogeneity, when present, in subgroup analyses of participant age and percentage of participants with confirmed Shigella infection. Sixteen trials (1748 participants), spanning four decades and with differing sensitivity to Shigella isolates, met the inclusion criteria. Seven were judged to be at risk of bias due to inadequate allocation concealment or blinding, and 12 due to incomplete reporting of outcome data. Limited data from one three-armed trial of people with moderately severe illness suggest that antibiotics reduce the episodes of diarrhoea at follow-up (furazolidone versus no drug RR 0.21, 95% CI 0.09 to 0.48, 73 participants; cotrimoxazole versus no drug RR 0.30, 95% CI 0.15 to 0.59, 76 participants).There was insufficient evidence to consider any class of antibiotic superior in efficacy in treating Shigella dysentery, but heterogeneity for some comparisons limits confidence in the results. All the antibiotics studied were safe. There was inadequate evidence regarding the role of antibiotics in preventing relapses. Antibiotics reduce the duration of Shigella dysentery.Regularly updated local or regional antibiotic sensitivity patterns to different species and strains of Shigella are required to guide empiric therapy. More trials adhering to standard guidelines are required to evaluate the role of antibiotics in the treatment of severe forms of Shigella dysentery and in groups who are at high risk of complications.

Asymptomatic bacteriuria among antenatal women in Lagos.

PubMed

Olamijulo, Joseph Ayodeji; Adewale, Chris Olu; Olaleye, Olalekan

2016-08-01

This cross-sectional study was undertaken to determine the prevalence of asymptomatic bacteriuria (ASB), the commonest bacterial isolates and the antibiotic sensitivity pattern among 556 pregnant women in Lagos University Teaching Hospital (LUTH), Nigeria. Women with a bacterial count over 100,000 colony-forming units per millilitre of the same organisms in paired urine samples were considered to have ASB. The prevalence of ASB was 14.6%. Klebsiella was the commonest micro-organism (39.2%) isolated. ASB was significantly associated with marital status, body mass index and parity. There was a significant relationship between urinary nitrites and ASB. The isolated organisms showed remarkable resistance to commonly prescribed antibiotics such as amoxicillin, cloxacillin and trimethoprim but good sensitivity to ofloxacin, gentamycin and ceftazidime. These facts have implications for the management of ASB in pregnancy.

Clinical test to detect mecA and antibiotic resistance in Staphylococcus aureus, based on novel biotechnological methods.

PubMed

Shahmohammadi, Mohammad Reza; Nahaei, Mohammad Reza; Akbarzadeh, Abolfazl; Milani, Morteza

2016-09-01

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common organisms isolated from clinical samples, and has been associated with morbidity and mortality among hospitalized patients. The aim of this study was to evaluate the prevalence and antibiotic susceptibility patterns among MRSA and methicillin-sensitive S. aureus (MSSA) isolates collected from four hospitals in Iran. A total of 183 isolates of S. aureus were collected from various clinical specimens of four hospitals in Iran. The isolates were identified by using the conventional biochemical tests. Three methods-oxacillin agar disk diffusion, oxacillin agar screening, and PCR- were applied to determine susceptibility to oxacillin. The conventional disk agar diffusion test was used to evaluate the antibiotic sensitivity of our isolates against 15 antibiotics, according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Of 183 isolates, 77 isolates (42.1%) were found to be MRSA, by the PCR method. The highest antibiotic resistance was found to be against penicillin, co-trimoxazole, erythromycin, and tetracycline respectively. All isolates were susceptible to vancomycin, according to the results of disk agar diffusion. Among other antibiotics, teicoplanin (84%) and fusidic acid (80.5%) were more active against MRSA isolates. For the different methods evaluated, the sensitivities and specificities were as follows: for disk agar diffusion (84.9% and 95.9%) and for agar screening test with oxacillin concentrations of 0.6 μg/ml (70.8% and 97.4%), 4 μg/ml (96.1%and 97.2%) and 6 μg/ml (96% and 96.3%), respectively. The results of our study showed that 47% of S. aureus isolates were MRSA. Overall, in this research study, resistance to all test antimicrobial agents in MRSA isolates were higher than that of MSSA isolates. Our results also revealed that 85% of mecA-positive isolates and 15% of mecA-negative isolates were resistant to methicillin; while 96% of mecA-negative isolates were sensitive to methicillin. Meanwhile 4% of mecA-positive isolates were also sensitive to methicillin.

Bacteriophages for treating urinary tract infections in patients undergoing transurethral resection of the prostate: a randomized, placebo-controlled, double-blind clinical trial.

PubMed

Leitner, Lorenz; Sybesma, Wilbert; Chanishvili, Nina; Goderdzishvili, Marina; Chkhotua, Archil; Ujmajuridze, Aleksandre; Schneider, Marc P; Sartori, Andrea; Mehnert, Ulrich; Bachmann, Lucas M; Kessler, Thomas M

2017-09-26

Urinary tract infections (UTI) are among the most prevalent microbial diseases and their financial burden on society is substantial. The continuing increase of antibiotic resistance worldwide is alarming. Thus, well-tolerated, highly effective therapeutic alternatives are urgently needed. Although there is evidence indicating that bacteriophage therapy may be effective and safe for treating UTIs, the number of investigated patients is low and there is a lack of randomized controlled trials. This study is the first randomized, placebo-controlled, double-blind trial investigating bacteriophages in UTI treatment. Patients planned for transurethral resection of the prostate are screened for UTIs and enrolled if in urine culture eligible microorganisms ≥10 4 colony forming units/mL are found. Patients are randomized in a double-blind fashion to the 3 study treatment arms in a 1:1:1 ratio to receive either: a) bacteriophage (i.e. commercially available Pyo bacteriophage) solution, b) placebo solution, or c) antibiotic treatment according to the antibiotic sensitivity pattern. All treatments are intended for 7 days. No antibiotic prophylaxes will be given to the double-blinded treatment arms a) and b). As common practice, the Pyo bacteriophage cocktail is subjected to periodic adaptation cycles during the study. Urinalysis, urine culture, bladder and pain diary, and IPSS questionnaire will be completed prior to and at the end of treatment (i.e. after 7 days) or at withdrawal/drop out from the study. Patients with persistent UTIs will undergo antibiotic treatment according to antibiotic sensitivity pattern. Based on the high lytic activity and the potential of resistance optimization by direct adaptation of bacteriophages, and considering the continuing increase of antibiotic resistance worldwide, bacteriophage therapy is a very promising treatment option for UTIs. Thus, our randomized controlled trial investigating bacteriophages for treating UTIs will provide essential insights into this potentially revolutionizing treatment option. This study has been registered at clinicaltrials.gov ( www.clinicaltrials.gov/ct2/show/NCT03140085 ). April 27, 2017.

Invasive bacterial infections in a pediatric oncology unit in a tertiary care center.

PubMed

Trehan, A; Totadri, S; Gautam, V; Bansal, D; Ray, P

2014-01-01

Multidrug resistant (MDR) pathogens are becoming a major problem worldwide, more so in the immunocompromised hosts resulting in the urgent need of antibiotic stewardship. To analyze the organisms isolated and the drug resistance pattern in a pediatric oncology unit. Data pertaining to infections with 128 positive cultures in patients with febrile neutropenia over a period of 1-year are presented. The unit antibiotic policy is decided depending on the sensitivity of the prevailing common organisms. We isolated Gram-negative organisms in 56% cases. Escherichia coli and Klebseilla were the most frequent lactose fermenting Gram-negative Bacilli and Pseudomonas and Acinetobacter the nonfermenting Gram-negative Bacilli. Only 20-30% of the Gram-negative organisms cultured were sensitive to a 3rd/4th generation cephalosporin. The combination of a beta-lactam/inhibitor covered 2/3rd of Gram-negative organisms. About 80% of the organisms were sensitive to carbapenems. There was no colistin resistance. About 44% of our cultures grew a Gram-positive bacterial organism and included coagulase negative Staphylococcus. We had an incidence of methicillin resistant Staphylococcus aureus to be 30%. About 30% of the enterococci isolated in our unit were vancomycin-resistant enterococci. About 23% of patients with a positive bacterial culture died. Infections in pediatric cancer patient's account for about 15-20% of the deaths in developing countries as these patients are at a high risk for developing MDR infections. Resistance rates among Gram-positive and Gram-negative organisms have increased worldwide. Every unit needs a rational antibiotic policy. Antibiotic de-escalation and judicious decrease in the duration of antibiotics needs to be practiced.

Characterization and susceptibility patterns of clinically important Enterococcus species in eastern Nepal.

PubMed

Acharya, A; Khanal, A; Kanungo, R; Mohapatra, T

2007-12-01

Life threatening infections caused by enterococcus species with multidrug resistance has emerged as a threat to medical care in the present era. This study was conducted to characterize enterococcus species isolated from different clinical samples and to detect the pattern of susceptibility to some of the commonly used antibiotics in B.P Koirala Institute of Health Sciences (BPKIHS), a tertiary care hospital in eastern Nepal. Clinical samples submitted to the microbiology unit of Central Laboratory Service (CLS) for culture and sensitivity during March 2002 - February 2003 was analyzed. Enterococcus species were identified by colony characteristics, gram staining and relevant biochemical tests. Antibiotic susceptibility test was done by the Kirby Bauer disc diffusion technique. Of 50 Enterococcus species isolated, E. faecalis was the predominant isolate (48.0%) followed by E. faecium (32.0%) and E. avium (20.0%). Eighty-eight percent of E. faecalis showed sensitivity to cephotaxime and 87.0% to vancomycin. Multiple drug resistance was observed most commonly in E. faecium. Seventeen percent of E. faecium were resistant to vancomycin and 63.0% to ciprofloxacin and 44.0% to ampicillin. On the contrary E. avium rarely showed resistance to the antimicrobials tested including vancomycin. Enterococcal infections are common nowadays specially in hospitalized patients. Inappropriate use of antibiotics in clinical practice and poultry should be discouraged to prevent the emergence of multidrug resistant species.

Antibiotic-resistant bacteria show widespread collateral sensitivity to antimicrobial peptides.

PubMed

Lázár, Viktória; Martins, Ana; Spohn, Réka; Daruka, Lejla; Grézal, Gábor; Fekete, Gergely; Számel, Mónika; Jangir, Pramod K; Kintses, Bálint; Csörgő, Bálint; Nyerges, Ákos; Györkei, Ádám; Kincses, András; Dér, András; Walter, Fruzsina R; Deli, Mária A; Urbán, Edit; Hegedűs, Zsófia; Olajos, Gábor; Méhi, Orsolya; Bálint, Balázs; Nagy, István; Martinek, Tamás A; Papp, Balázs; Pál, Csaba

2018-06-01

Antimicrobial peptides are promising alternative antimicrobial agents. However, little is known about whether resistance to small-molecule antibiotics leads to cross-resistance (decreased sensitivity) or collateral sensitivity (increased sensitivity) to antimicrobial peptides. We systematically addressed this question by studying the susceptibilities of a comprehensive set of 60 antibiotic-resistant Escherichia coli strains towards 24 antimicrobial peptides. Strikingly, antibiotic-resistant bacteria show a high frequency of collateral sensitivity to antimicrobial peptides, whereas cross-resistance is relatively rare. We identify clinically relevant multidrug-resistance mutations that increase bacterial sensitivity to antimicrobial peptides. Collateral sensitivity in multidrug-resistant bacteria arises partly through regulatory changes shaping the lipopolysaccharide composition of the bacterial outer membrane. These advances allow the identification of antimicrobial peptide-antibiotic combinations that enhance antibiotic activity against multidrug-resistant bacteria and slow down de novo evolution of resistance. In particular, when co-administered as an adjuvant, the antimicrobial peptide glycine-leucine-amide caused up to 30-fold decrease in the antibiotic resistance level of resistant bacteria. Our work provides guidelines for the development of efficient peptide-based therapies of antibiotic-resistant infections.

[Antibiotic consumption and bacterial sensitivity in a teaching hospital: A 5-year study].

PubMed

Cotteret, C; Vallières, E; Roy, H; Ovetchkine, P; Longtin, J; Bussières, J-F

2016-10-01

To reduce risks of antibiotic resistance, governmental and learned societies decreed the optimal use of antibiotics. The relation between antibiotic consumption and bacterial resistance increase has been clearly demonstrated over the last several years. Antibiotic consumption data and bacterial sensitivity data are regularly published, but very few publications have searched for a correlation between these two variables. This study focused on antibiotic use and consumption as well as bacterial sensitivity to these antibiotics. The main objective was to describe the changes in antibiotic consumption and bacterial sensitivity in a mother-child teaching hospital. The secondary objectives were to explore whether antibiotic use and bacterial sensitivity were correlated and to comment on the usefulness of these data for clinicians. This was a 5-year retrospective, descriptive, cross-sectional study. All samples from usually sterile biologic liquids of hospitalized pediatric patients were included in the study. The samples from outpatient clinics were excluded. All types of bacteria identified in more than 30 isolates were included in the study. The antibiotics usually used to treat these bacteria were included. To assess antibiotic consumption, we calculated the number of days of therapy per 1000 patient-days for hospitalized pediatric patients and we calculated the Pearson correlation coefficient between antibiotic consumption and sensitivity rates to these antibiotics. Two scenarios were explored: one with correlation by year and one with the next year for bacterial sensitivity. During the study period (2010-2011 to 2014-2015), overall antibiotics consumption remained relatively stable. Concerning bacterial sensitivity, we noted important changes (sensitivity rates increased for 12 antibiotic-bacteria pairs, remained stable for five, and decreased for 15). We found three significant correlations for the first scenario: Pseudomonas aeruginos-ceftazidime (P=0.01), P. aeruginosa-ciprofloxacin and fluoroquinolone consumption (P=0.02), Enterococcus sp-ampicillin and penicillin consumption (P=0.04). For the second scenario, we found only two significant correlations: coagulase-negative Staphylococcus-oxacilline and penicillin consumption (P=0.02), P. aeruginosa/piperacillin (P=0.04). This exploratory study allowed us to describe antibiotic consumption and bacterial sensitivity progression. To our knowledge, this is the first study exploring the correlation between antibiotic consumption and the bacterial sensitivity rate in pediatrics in Canada. It remains very difficult to show this correlation between these two variables because of the multiple sources of bacterial resistance. These data are particularly useful for the antimicrobial stewardship programs and for clinicians. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Asymptomatic bacteriuria among an obstetric population in Ibadan.

PubMed

Awonuga, D O; Dada-Adegbola, H O; Fawole, A O; Olala, F A; Onimisi-Smith, H O

2011-01-01

Asymptomatic bacteriuria in pregnancy is the major risk factor for symptomatic urinary tract infection during pregnancy. Screening and identification of bacteriuria during pregnancy have been recommended. To determine the prevalence and pattern of asymptomatic bacteriuria associated with pregnancy. The study was a descriptive, cross sectional survey of pattern of asymptomatic bacteriuria among consecutive patients presenting for the first antenatal visit at a University College Hospital, during a period of two months. Relevant information obtained from all the patients recruited for the study included age, parity, educational level, gestational age and occupation of participant. Haemoglobin electrophoresis patterns were also retrieved and recorded. Main outcome measures were prevalence of asymptomatic bacteriuria, bacterial isolates and their antibiotic sensitivities. There were 205 eligible participants with a mean age of 30.6 ± 4.3 years and a mean gestational age at booking of 20.9 ±7.0 weeks. The prevalence of asymptomatic bacteriuria was 22(10.7%). The isolated pathogens were predominantly coliforms (Klebsiella and E. coli) accounting for 45.5% and Staphylococcus saprophyticus (27.3%). Only gentamycin, nitrofurantoin and ofloxacin demonstrated high efficacy against these uropathogens with antibiotic sensitivity rates of 72.7%-81.8%. Prevalence of asymptomatic bacteriuria in this centre is relatively high. This underscores the need for routine screening of pregnant women for bacteriuria.

Reversing Bacterial Resistance to Antibiotics by Phage-Mediated Delivery of Dominant Sensitive Genes

PubMed Central

Edgar, Rotem; Friedman, Nir; Molshanski-Mor, Shahar

2012-01-01

Pathogen resistance to antibiotics is a rapidly growing problem, leading to an urgent need for novel antimicrobial agents. Unfortunately, development of new antibiotics faces numerous obstacles, and a method that resensitizes pathogens to approved antibiotics therefore holds key advantages. We present a proof of principle for a system that restores antibiotic efficiency by reversing pathogen resistance. This system uses temperate phages to introduce, by lysogenization, the genes rpsL and gyrA conferring sensitivity in a dominant fashion to two antibiotics, streptomycin and nalidixic acid, respectively. Unique selective pressure is generated to enrich for bacteria that harbor the phages carrying the sensitizing constructs. This selection pressure is based on a toxic compound, tellurite, and therefore does not forfeit any antibiotic for the sensitization procedure. We further demonstrate a possible way of reducing undesirable recombination events by synthesizing dominant sensitive genes with major barriers to homologous recombination. Such synthesis does not significantly reduce the gene's sensitization ability. Unlike conventional bacteriophage therapy, the system does not rely on the phage's ability to kill pathogens in the infected host, but instead, on its ability to deliver genetic constructs into the bacteria and thus render them sensitive to antibiotics prior to host infection. We believe that transfer of the sensitizing cassette by the constructed phage will significantly enrich for antibiotic-treatable pathogens on hospital surfaces. Broad usage of the proposed system, in contrast to antibiotics and phage therapy, will potentially change the nature of nosocomial infections toward being more susceptible to antibiotics rather than more resistant. PMID:22113912

Reversing bacterial resistance to antibiotics by phage-mediated delivery of dominant sensitive genes.

PubMed

Edgar, Rotem; Friedman, Nir; Molshanski-Mor, Shahar; Qimron, Udi

2012-02-01

Pathogen resistance to antibiotics is a rapidly growing problem, leading to an urgent need for novel antimicrobial agents. Unfortunately, development of new antibiotics faces numerous obstacles, and a method that resensitizes pathogens to approved antibiotics therefore holds key advantages. We present a proof of principle for a system that restores antibiotic efficiency by reversing pathogen resistance. This system uses temperate phages to introduce, by lysogenization, the genes rpsL and gyrA conferring sensitivity in a dominant fashion to two antibiotics, streptomycin and nalidixic acid, respectively. Unique selective pressure is generated to enrich for bacteria that harbor the phages carrying the sensitizing constructs. This selection pressure is based on a toxic compound, tellurite, and therefore does not forfeit any antibiotic for the sensitization procedure. We further demonstrate a possible way of reducing undesirable recombination events by synthesizing dominant sensitive genes with major barriers to homologous recombination. Such synthesis does not significantly reduce the gene's sensitization ability. Unlike conventional bacteriophage therapy, the system does not rely on the phage's ability to kill pathogens in the infected host, but instead, on its ability to deliver genetic constructs into the bacteria and thus render them sensitive to antibiotics prior to host infection. We believe that transfer of the sensitizing cassette by the constructed phage will significantly enrich for antibiotic-treatable pathogens on hospital surfaces. Broad usage of the proposed system, in contrast to antibiotics and phage therapy, will potentially change the nature of nosocomial infections toward being more susceptible to antibiotics rather than more resistant.

Developing biochemical and molecular markers for cyanobacterial inoculants.

PubMed

Prasanna, R; Madhan, K; Singh, R N; Chauhan, A K; Nain, L

2010-09-01

Markers for evaluating the establishment of cyanobacteria based on their sensitivity or resistance to antibiotics, saccharide utilization patterns and PCR generated fingerprints were developed. Four selected strains (isolates from rhizosphere soils of diverse agro-ecosystems) have shown potential as diazotrophs and exhibited plant growth promoting abilities. Different responses were obtained on screening against 40 antibiotics, which aided in developing selectable antibiotic markers for each strain. Biochemical profiles generated using standardized chromogenic identification system (including saccharide utilization tests) revealed that 53 % of the saccharides tested were not utilized by any strain, while some strains exhibited unique ability for utilization of saccharides such as melibiose, cellobiose, maltose and glucosamine. PCR based amplification profiles developed using a number of primers based on repeat sequences revealed the utility of 3 primers in providing unique fingerprints for the strains.

Impact of Rapid Susceptibility Testing and Antibiotic Selection Strategy on the Emergence and Spread of Antibiotic Resistance in Gonorrhea

PubMed Central

Tuite, Ashleigh R; Gift, Thomas L; Chesson, Harrell W; Hsu, Katherine; Salomon, Joshua A; Grad, Yonatan H

2017-01-01

Abstract Background Increasing antibiotic resistance limits treatment options for gonorrhea. We examined the impact of a hypothetical point-of-care (POC) test reporting antibiotic susceptibility profiles on slowing resistance spread. Methods A mathematical model describing gonorrhea transmission incorporated resistance emergence probabilities and fitness costs associated with resistance based on characteristics of ciprofloxacin (A), azithromycin (B), and ceftriaxone (C). We evaluated time to 1% and 5% prevalence of resistant strains among all isolates with the following: (1) empiric treatment (B and C), and treatment guided by POC tests determining susceptibility to (2) A only and (3) all 3 antibiotics. Results Continued empiric treatment without POC testing was projected to result in >5% of isolates being resistant to both B and C within 15 years. Use of either POC test in 10% of identified cases delayed this by 5 years. The 3 antibiotic POC test delayed the time to reach 1% prevalence of triply-resistant strains by 6 years, whereas the A-only test resulted in no delay. Results were less sensitive to assumptions about fitness costs and test characteristics with increasing test uptake. Conclusions Rapid diagnostics reporting antibiotic susceptibility may extend the usefulness of existing antibiotics for gonorrhea treatment, but ongoing monitoring of resistance patterns will be critical. PMID:28968710

Urinary tract infections in pregnancy: evaluation of diagnostic framework.

PubMed

Jido, Tukur Ado

2014-01-01

This study was performed with the objective to examine the diagnostic framework for urinary tract infection (UTI) in pregnancy and physician response to the clinical diagnosis and to correlate responses to the results of urine culture and sensitivity. Over a 6-month period, 81 consecutive patients attending the labor ward admission of a district general hospital with the diagnosis of UTI during pregnancy were analyzed. Relevant information on symptom complex, result of dipstick urinalysis and culture and sensitivity were recorded. Data were analyzed using descriptive statistics. Of the 78 patients analyzed, 79% had increased urinary frequency, 73.1% had suprapubic pains and 53.1% had dysuria. All the patients had urinalysis with dipsticks, 41 (52.6%) were positive for nitrites and 64 (82.1%) were positive for leukocyte esterase. All 78 patients had urine culture and sensitivity, 21 (26.8%) of who were positive, and coliforms were the most commonly isolated pathogens. The sensitivity for nitrite was 80.9%, specificity 57.9% and positive predictive value 41.4%. The corresponding figures for leukocyte esterase were sensitivity 100%, specificity 24.6% and positive predictive value 32.8%. Sixty-six (84.6%) patients had treatment started on the basis of the clinical diagnosis, mostly with co-amoxyclavullinic acid or amoxicillin alone. A high resistance rate to these empirically chosen antibiotics was seen in the sensitivity pattern of isolated pathogens. Current clinical diagnostic algorithms for the diagnosis of UTI when applied in the context of pregnancy have low specificity and positive predictive values; yet, empirical antibiotics are frequently employed on this basis. These are often not in keeping with the sensitivity pattern of isolated organisms. There is need for a continuing research for more specific bedside tests.

Antimicrobial sensitivity pattern of bacterial pathogens in urinary tract infections in South Delhi, India.

PubMed

Akhtar, Mohammad Shabib; Mohsin, Nehal; Zahak, Ahmad; Ain, Mohammad Ruhal; Pillai, P K; Kapur, Prem; Ahmad, Mohammad Zaki

2014-01-01

Seventy-four bacterial proven cases of urinary tract infections were studied, and identified by Mac Conkey agar and blood agar medium separately; all the isolates were subjected to antimicrobial sensitivity testing by Stokes technique. Ninty-six percent of total isolated organisms were found to be gram negative while remaining 4% were gram positive. Among gram negatives, E. coli and gram positive S. aureus were the most prevalent organisms. The percentage of gram negative isolates were as follows, E. coli (79.7%) followed by Klebsiella (9.5%), Pseudomonas, Acinetobacter were (2.7% each), Proteus constituted (1.4%). and among gram positive S. aureus (4%). The antibiotic resistance of identified organisms was carried out by disc-diffusion method with commercially available disc of thirteen antibiotics having different mode of actions such as inhibition of cell wall synthesis, membrane permeability alternatives, inhibition of protein synthesis and DNA synthesis inhibitors. Gram negatives showed more resistance to these antibiotics as compared to gram positive organisms. The most effective antibiotic for gram negative UTI isolates is amikacin showing 63% efficacy followed by Cefotaxime 55% efficacy, Amoxicillin and Ciprofloxacin with (49% each) efficacy. Among gram positives, Chloramphenicol, Co-trimoxazole, Gentamicin, Amikacin, Ciprofloxacin and Cefotaxime are most effective with (66.6% each) efficacy, then Ampicillin, Amoxicillin, Tetracycline and norfloxacin with (33.3% each) efficacy.

Isolation and identification of Salmonella from curry samples and its sensitivity to commercial antibiotics and aqueous extracts of Camelia sinensis (L.) and Trachyspermum ammi (L.)

PubMed Central

Gunasegaran, Thanes; Rathinam, Xavier; Kasi, Marimuthu; Sathasivam, Kathiresan; Sreenivasan, Sasidharan; Subramaniam, Sreeramanan

2011-01-01

Objective To isolate Salmonella from curry samples and to evaluate the drug sensitivity of the food-borne Salmonella and its susceptibility to specific plant extracts. Methods Salmonella was isolated from the curry samples by standard microbiological methods and was confirmed by biochemical tests. The antibiotic susceptibility test was conducted by disc diffusion method using commercially available antibiotics such as ampicillin, tetracycline, chloramphenicol, kanamycin, and penicillin. In addition, the susceptibility of the food-borne Salmonella was also evaluated against the aqueous extracts of Camelia sinensis (L.) Theaceae (tea leaves) and the Trachyspermum ammi (L.) Apiaceae ( ajwain or omum seeds). Results Out of fifty curry samples, only seven samples were identified to have Salmonella contamination. The Salmonella isolates showed a significant drug resistance pattern except for kanamycin. The plant extracts showed a considerable antibacterial activity against the isolates, indicating the presence of antimicrobial principle which can be exploited after complete pharmacological investigations. Conclusions The present study demonstrates the occurrence of Salmonella in the curry samples, and shows significant drug resistance against most of the commercially available antibiotics, except kanamycin. Antimicrobial effect of the plant extracts against the food-bone Salmonella suggests that dietary including medicinal herbs would be one strategy to manage food borne pathogens. PMID:23569772

Changes in Bacterial Resistance Patterns of Pediatric Urinary Tract Infections and Rationale for Empirical Antibiotic Therapy.

PubMed

Gökçe, İbrahim; Çiçek, Neslihan; Güven, Serçin; Altuntaş, Ülger; Bıyıklı, Neşe; Yıldız, Nurdan; Alpay, Harika

2017-09-29

The causative agent spectrum and resistance patterns of urinary tract infections in children are affected by many factors. To demonstrate antibiotic resistance in urinary tract infections and changing ratio in antibiotic resistance by years. Retrospective cross-sectional study. We analysed antibiotic resistance patterns of isolated Gram (-) bacteria during the years 2011-2014 (study period 2) in children with urinary tract infections. We compared these findings with data collected in the same centre in 2001-2003 (study period 1). Four hundred and sixty-five uncomplicated community-acquired Gram (-) urinary tract infections were analysed from 2001-2003 and 400 from 2011-2014. Sixty-one percent of patients were female (1.5 girls : 1 boy). The mean age of children included in the study was 3 years and 9 months. Escherichia coli was the predominant bacteria isolated during both periods of the study (60% in study period 1 and 73% in study period 2). Bacteria other than E. coli demonstrated a higher level of resistance to all of the antimicrobials except trimethoprim-sulfamethoxazole than E. coli bacteria during the years 2011-2014. In our study, we found increasing resistance trends of urinary pathogens for cefixime (from 1% to 15%, p<0.05), amikacin (from 0% to 4%, p<0.05) and ciprofloxacin (from 0% to 3%, p<0.05) between the two periods. Urinary pathogens showed a decreasing trend for nitrofurantoin (from 17% to 7%, p=0.0001). No significant trends were detected for ampicillin (from 69% to 71%), amoxicillin-clavulanate (from 44% to 43%), cefazolin (from 39% to 32%), trimethoprim-sulfamethoxazole (from 32% to 31%), cefuroxime (from 21% to 18%) and ceftriaxone (from 10% to 14%) between the two periods (p>0.05). In childhood urinary tract infections, antibiotic resistance should be evaluated periodically and empiric antimicrobial therapy should be decided according to antibiotic sensitivity results.

Sublethal Concentrations of Antibiotics Cause Shift to Anaerobic Metabolism in Listeria monocytogenes and Induce Phenotypes Linked to Antibiotic Tolerance

PubMed Central

Knudsen, Gitte M.; Fromberg, Arvid; Ng, Yin; Gram, Lone

2016-01-01

The human pathogenic bacterium Listeria monocytogenes is exposed to antibiotics both during clinical treatment and in its saprophytic lifestyle. As one of the keys to successful treatment is continued antibiotic sensitivity, the purpose of this study was to determine if exposure to sublethal antibiotic concentrations would affect the bacterial physiology and induce antibiotic tolerance. Transcriptomic analyses demonstrated that each of the four antibiotics tested caused an antibiotic-specific gene expression pattern related to mode-of-action of the particular antibiotic. All four antibiotics caused the same changes in expression of several metabolic genes indicating a shift from aerobic to anaerobic metabolism and higher ethanol production. A mutant in the bifunctional acetaldehyde-CoA/alcohol dehydrogenase encoded by lmo1634 did not have altered antibiotic tolerance. However, a mutant in lmo1179 (eutE) encoding an aldehyde oxidoreductase where rerouting caused increased ethanol production was tolerant to three of four antibiotics tested. This shift in metabolism could be a survival strategy in response to antibiotics to avoid generation of ROS production from respiration by oxidation of NADH through ethanol production. The monocin locus encoding a cryptic prophage was induced by co-trimoxazole and repressed by ampicillin and gentamicin, and this correlated with an observed antibiotic-dependent biofilm formation. A monocin mutant (ΔlmaDCBA) had increased biofilm formation when exposed to increasing concentration of co-trimoxazole similar to the wild type, but was more tolerant to killing by co-trimoxazole and ampicillin. Thus, sublethal concentrations of antibiotics caused metabolic and physiological changes indicating that the organism is preparing to withstand lethal antibiotic concentrations. PMID:27462313

Pre- and post-natal exposure to antibiotics and the development of eczema, recurrent wheezing and atopic sensitization in children up to the age of 4 years.

PubMed

Dom, S; Droste, J H J; Sariachvili, M A; Hagendorens, M M; Oostveen, E; Bridts, C H; Stevens, W J; Wieringa, M H; Weyler, J J

2010-09-01

Little data are available on the relationship between indirect antibiotic exposure of the child in utero or during lactation and allergic diseases. On the other hand, several studies have been conducted on the association with direct post-natal antibiotic exposure, but the results are conflicting. The aim of this study was to investigate pre- and post-natal antibiotic exposure and the subsequent development of eczema, recurrent wheeze and atopic sensitization in children up to the age of 4 years. We conducted an aetiologic study in 773 children based on a prospective birth cohort project in which environmental and health information were collected using questionnaires. Antibiotic exposure was assessed as maternal antibiotic intake during pregnancy and during lactation and as medication intake of the child. The chronology of exposures and outcomes was taken into account during the data processing. At the age of 1 and 4 years, a blood sample was taken for the quantification of specific IgE. Prenatal antibiotic exposure was significantly positively associated with eczema, whereas no association was found with recurrent wheeze and atopic sensitization. We found a positive, although statistically not significant, association between antibiotic exposure through breastfeeding and recurrent wheeze. Neither eczema nor atopic sensitization was significantly associated with antibiotic exposure through breastfeeding. Finally, we observed a negative association between the use of antibiotics in the first year of life and eczema and atopic sensitization, and also between antibiotic use after the first year of life and recurrent wheeze, eczema and atopic sensitization. Indirect exposure to antibiotics (in utero and during lactation) increases the risk for allergic symptoms in children, while direct exposure to antibiotics appears to be protective. The biological mechanisms underlying these findings still need to be elucidated.

Antibiotic Resistance Patterns of Gram-Negative Psychrotrophic Bacteria from Bulk Tank Milk.

PubMed

Decimo, Marilù; Silvetti, Tiziana; Brasca, Milena

2016-04-01

Bacterial resistance to antibiotics is a major global health problem and resistance of Pseudomonadaceae and Enterobacteriaceae is a serious concern. We investigated the prevalence of drug-resistance in a total of 80 psychrotrophic strains from bulk milk belonging to Pseudomonas genus (n. 63) and Enterobacteriaceae group (n. 17). All the strains were tested against 16 antibiotics. Pseudomonas were further investigated for their sensitivity against 12 additional antibiotics. Pseudomonas showed a high susceptibility toward fluoroquinolones, aminoglycosides, and piperacillin and, to a lesser extent, to imipenem, ceftazidime, cefepime. Thirty-five out of 63 Pseudomonas strains were susceptible to meropenem, while among antibiotics for which recommended breakpoints are not yet available, 55% of Pseudomonas strains had no inhibition halo in presence of nitrofurantoin, highlighting a resistance toward this drug. The results obtained in this study indicate a high efficiency of fluoroquinolones, chloramphenicol (94%), and kanamycin (76%) for Enterobacteriaceae while a high prevalence of resistant strains was found to ampicillin (13/17). Serratia marcescens is highly susceptible to fluoroquinolones, chloramphenicol, and kanamycin. Moreover, mupirocin seems to be the new antibiotic with the less efficacy for Enterobacteriaceae, with 41% of strains without halo, pointing out an important resistance. Further knowledge on resistance to known and new antibiotics among Pseudomonas species and Enterobacteriaceae of milk origin was acquired. © 2016 Institute of Food Technologists®

[Micromonospora resistence to definite antibiotics and their ability to produce structurally analogous antibiotics].

PubMed

Bibikova, M V; Ivanitskaia, L P; Tikhonova, A S

1980-01-01

Thirty six cultures of Micromonospora freshly isolated from soil samples were studied with respect to their sensitivity to a number of antibiotics of various structures and modes of action. It was found that all of them were highly sensitive to penicillin, ristomycin, tetracycline, rifampicin, streptomycin, olivomycin, carminomycin and dactinomycin. Significant differences in sensitivity of the Micromonospora cultures were revealed only with respect to gentamicin, tobramicin, erythromycin and lincomycin. Seven cultures were resistant to gentamicin and tobramicin and sensitive to all of the other antibiotics. Broad spectrum antibiotics were isolated from these cultures. The study of the antibiotic chemistry showed that they were 2-desoxystreptamine-containing aminoglycosides. Two cultures proved to be resistant to erythromycin and lincomycin. When identified with the use of antibiotic resistant staphylococcal strains, the crude antibiotic substances isolated from these cultures appeared to be not active against staphylococci resistant to erythromycin and lincomycin. By their chromatograpi- behaviour the antibiotics were close to macrolides. Therefore, it was found that production of aminoglycoside and macrolide antibiotics was most characteristic of Micromonospora. A certain correlation between resistance of Micromonospora to these 2 antibiotic groups and capacity for their production was shown.

The human milk protein-lipid complex HAMLET sensitizes bacterial pathogens to traditional antimicrobial agents.

PubMed

Marks, Laura R; Clementi, Emily A; Hakansson, Anders P

2012-01-01

The fight against antibiotic resistance is one of the most significant challenges to public health of our time. The inevitable development of resistance following the introduction of novel antibiotics has led to an urgent need for the development of new antibacterial drugs with new mechanisms of action that are not susceptible to existing resistance mechanisms. One such compound is HAMLET, a natural complex from human milk that kills Streptococcus pneumoniae (the pneumococcus) using a mechanism different from common antibiotics and is immune to resistance-development. In this study we show that sublethal concentrations of HAMLET potentiate the effect of common antibiotics (penicillins, macrolides, and aminoglycosides) against pneumococci. Using MIC assays and short-time killing assays we dramatically reduced the concentrations of antibiotics needed to kill pneumococci, especially for antibiotic-resistant strains that in the presence of HAMLET fell into the clinically sensitive range. Using a biofilm model in vitro and nasopharyngeal colonization in vivo, a combination of HAMLET and antibiotics completely eradicated both biofilms and colonization in mice of both antibiotic-sensitive and resistant strains, something each agent alone was unable to do. HAMLET-potentiation of antibiotics was partially due to increased accessibility of antibiotics to the bacteria, but relied more on calcium import and kinase activation, the same activation pathway HAMLET uses when killing pneumococci by itself. Finally, the sensitizing effect was not confined to species sensitive to HAMLET. The HAMLET-resistant respiratory species Acinetobacter baumanii and Moraxella catarrhalis were all sensitized to various classes of antibiotics in the presence of HAMLET, activating the same mechanism as in pneumococci. Combined these results suggest the presence of a conserved HAMLET-activated pathway that circumvents antibiotic resistance in bacteria. The ability to activate this pathway may extend the lifetime of the current treatment arsenal.

The Human Milk Protein-Lipid Complex HAMLET Sensitizes Bacterial Pathogens to Traditional Antimicrobial Agents

PubMed Central

Marks, Laura R.; Clementi, Emily A.; Hakansson, Anders P.

2012-01-01

The fight against antibiotic resistance is one of the most significant challenges to public health of our time. The inevitable development of resistance following the introduction of novel antibiotics has led to an urgent need for the development of new antibacterial drugs with new mechanisms of action that are not susceptible to existing resistance mechanisms. One such compound is HAMLET, a natural complex from human milk that kills Streptococcus pneumoniae (the pneumococcus) using a mechanism different from common antibiotics and is immune to resistance-development. In this study we show that sublethal concentrations of HAMLET potentiate the effect of common antibiotics (penicillins, macrolides, and aminoglycosides) against pneumococci. Using MIC assays and short-time killing assays we dramatically reduced the concentrations of antibiotics needed to kill pneumococci, especially for antibiotic-resistant strains that in the presence of HAMLET fell into the clinically sensitive range. Using a biofilm model in vitro and nasopharyngeal colonization in vivo, a combination of HAMLET and antibiotics completely eradicated both biofilms and colonization in mice of both antibiotic-sensitive and resistant strains, something each agent alone was unable to do. HAMLET-potentiation of antibiotics was partially due to increased accessibility of antibiotics to the bacteria, but relied more on calcium import and kinase activation, the same activation pathway HAMLET uses when killing pneumococci by itself. Finally, the sensitizing effect was not confined to species sensitive to HAMLET. The HAMLET-resistant respiratory species Acinetobacter baumanii and Moraxella catarrhalis were all sensitized to various classes of antibiotics in the presence of HAMLET, activating the same mechanism as in pneumococci. Combined these results suggest the presence of a conserved HAMLET-activated pathway that circumvents antibiotic resistance in bacteria. The ability to activate this pathway may extend the lifetime of the current treatment arsenal. PMID:22905269

Molecular characterization and determination of antimicrobial resistance of Mycoplasma gallisepticum isolated from chickens.

PubMed

Pakpinyo, Somsak; Sasipreeyajan, Jiroj

2007-11-15

In this study, three consecutive approaches of molecular characterization, determination of minimum inhibitory concentration (MIC) and antimicrobial tested on Mycoplasma gallisepticum (MG) isolated from chicken farms were investigated. These approaches were conducted between 2004 and 2005 to 134 MG samples collected from five different regions of the intensive farming area of Thailand. Twenty MG isolates and four reference strains including S6, F, ts-11, and 6/85 were classified according to Random Amplification of Polymorphic DNA (RAPD) patterns prior to the antimicrobial tests. These isolates exhibited 5 different genotypes (A-E). Consequently, MG isolates representing each genotype were tested on 11 registered antibiotics. The levels of MIC were determined. Three antibiotics, doxycycline (0.20 microg/ml), tiamulin (0.10 microg/ml), and tylosin (0.33 microg/ml), gave the least MICs among all effective drugs. Break point comparisons of each antimicrobial suggested that the MG isolates were most sensitive to lincomycin, oxytetracycline, tiamulin, and tylosin. Some MG isolates had an intermediate effect on josamycin and were resistant to enrofloxacin and erythromycin. Our results also indicated that MG isolated and collected from the region and nearby districts had similar RAPD patterns showing properties of antimicrobial resistance. The RAPD patterns may imply the frequent use of antibiotics and a resistant strain of MG. This is the first report of genetic characterization using RAPD reflected by the levels of MIC against MG. The information is useful to plan for prophylactic and therapeutic impacts on the poultry industry especially in the area of intensive use of antibiotics.

Antibiotic Resistance Determinants in a Pseudomonas putida Strain Isolated from a Hospital

PubMed Central

Duque, Estrella; Fernández, Matilde; Molina-Santiago, Carlos; Roca, Amalia; Porcel, Mario; de la Torre, Jesús; Segura, Ana; Plesiat, Patrick; Jeannot, Katy; Ramos, Juan-Luis

2014-01-01

Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267) kills insects and is resistant to the majority of the antibiotics used in laboratories and hospitals, including aminoglycosides, ß-lactams, cationic peptides, chromoprotein enediyne antibiotics, dihydrofolate reductase inhibitors, fluoroquinolones and quinolones, glycopeptide antibiotics, macrolides, polyketides and sulfonamides. Similar to other P. putida clinical isolates the strain was sensitive to amikacin. To shed light on the broad pattern of antibiotic resistance, which is rarely found in clinical isolates of this species, the genome of this strain was sequenced and analysed. The study revealed that the determinants of multiple resistance are both chromosomally-borne as well as located on the pPC9 plasmid. Further analysis indicated that pPC9 has recruited antibiotic and biocide resistance genes from environmental microorganisms as well as from opportunistic and true human pathogens. The pPC9 plasmid is not self-transmissible, but can be mobilized by other bacterial plasmids making it capable of spreading antibiotic resistant determinants to new hosts. PMID:24465371

Bacterial clonal diagnostics as a tool for evidence-based empiric antibiotic selection

PubMed Central

Tchesnokova, Veronika; Avagyan, Hovhannes; Rechkina, Elena; Chan, Diana; Muradova, Mariya; Haile, Helen Ghirmai; Radey, Matthew; Weissman, Scott; Riddell, Kim; Scholes, Delia; Johnson, James R.

2017-01-01

Despite the known clonal distribution of antibiotic resistance in many bacteria, empiric (pre-culture) antibiotic selection still relies heavily on species-level cumulative antibiograms, resulting in overuse of broad-spectrum agents and excessive antibiotic/pathogen mismatch. Urinary tract infections (UTIs), which account for a large share of antibiotic use, are caused predominantly by Escherichia coli, a highly clonal pathogen. In an observational clinical cohort study of urgent care patients with suspected UTI, we assessed the potential for E. coli clonal-level antibiograms to improve empiric antibiotic selection. A novel PCR-based clonotyping assay was applied to fresh urine samples to rapidly detect E. coli and the urine strain's clonotype. Based on a database of clonotype-specific antibiograms, the acceptability of various antibiotics for empiric therapy was inferred using a 20%, 10%, and 30% allowed resistance threshold. The test's performance characteristics and possible effects on prescribing were assessed. The rapid test identified E. coli clonotypes directly in patients’ urine within 25–35 minutes, with high specificity and sensitivity compared to culture. Antibiotic selection based on a clonotype-specific antibiogram could reduce the relative likelihood of antibiotic/pathogen mismatch by ≥ 60%. Compared to observed prescribing patterns, clonal diagnostics-guided antibiotic selection could safely double the use of trimethoprim/sulfamethoxazole and minimize fluoroquinolone use. In summary, a rapid clonotyping test showed promise for improving empiric antibiotic prescribing for E. coli UTI, including reversing preferential use of fluoroquinolones over trimethoprim/sulfamethoxazole. The clonal diagnostics approach merges epidemiologic surveillance, antimicrobial stewardship, and molecular diagnostics to bring evidence-based medicine directly to the point of care. PMID:28350870

Bacterial clonal diagnostics as a tool for evidence-based empiric antibiotic selection.

PubMed

Tchesnokova, Veronika; Avagyan, Hovhannes; Rechkina, Elena; Chan, Diana; Muradova, Mariya; Haile, Helen Ghirmai; Radey, Matthew; Weissman, Scott; Riddell, Kim; Scholes, Delia; Johnson, James R; Sokurenko, Evgeni V

2017-01-01

Despite the known clonal distribution of antibiotic resistance in many bacteria, empiric (pre-culture) antibiotic selection still relies heavily on species-level cumulative antibiograms, resulting in overuse of broad-spectrum agents and excessive antibiotic/pathogen mismatch. Urinary tract infections (UTIs), which account for a large share of antibiotic use, are caused predominantly by Escherichia coli, a highly clonal pathogen. In an observational clinical cohort study of urgent care patients with suspected UTI, we assessed the potential for E. coli clonal-level antibiograms to improve empiric antibiotic selection. A novel PCR-based clonotyping assay was applied to fresh urine samples to rapidly detect E. coli and the urine strain's clonotype. Based on a database of clonotype-specific antibiograms, the acceptability of various antibiotics for empiric therapy was inferred using a 20%, 10%, and 30% allowed resistance threshold. The test's performance characteristics and possible effects on prescribing were assessed. The rapid test identified E. coli clonotypes directly in patients' urine within 25-35 minutes, with high specificity and sensitivity compared to culture. Antibiotic selection based on a clonotype-specific antibiogram could reduce the relative likelihood of antibiotic/pathogen mismatch by ≥ 60%. Compared to observed prescribing patterns, clonal diagnostics-guided antibiotic selection could safely double the use of trimethoprim/sulfamethoxazole and minimize fluoroquinolone use. In summary, a rapid clonotyping test showed promise for improving empiric antibiotic prescribing for E. coli UTI, including reversing preferential use of fluoroquinolones over trimethoprim/sulfamethoxazole. The clonal diagnostics approach merges epidemiologic surveillance, antimicrobial stewardship, and molecular diagnostics to bring evidence-based medicine directly to the point of care.

Bacterial Species and Antibiotic Sensitivity in Korean Patients Diagnosed with Acute Otitis Media and Otitis Media with Effusion.

PubMed

Kim, Sang Hoon; Jeon, Eun Ju; Hong, Seok Min; Bae, Chang Hoon; Lee, Ho Yun; Park, Moo Kyun; Byun, Jae Yong; Kim, Myung Gu; Yeo, Seung Geun

2017-04-01

Changes over time in pathogens and their antibiotic sensitivity resulting from the recent overuse and misuse of antibiotics in otitis media (OM) have complicated treatment. This study evaluated changes over 5 years in principal pathogens and their antibiotic sensitivity in patients in Korea diagnosed with acute OM (AOM) and OM with effusion (OME). The study population consisted of 683 patients who visited the outpatient department of otorhinolaryngology in 7 tertiary hospitals in Korea between January 2010 and May 2015 and were diagnosed with acute AOM or OME. Aural discharge or middle ear fluid were collected from patients in the operating room or outpatient department and subjected to tests of bacterial identification and antibiotic sensitivity. The overall bacteria detection rate of AOM was 62.3% and OME was 40.9%. The most frequently isolated Gram-positive bacterial species was coagulase negative Staphylococcus aureus (CNS) followed by methicillin-susceptible S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), and Streptococcus pneumonia (SP), whereas the most frequently isolated Gram-negative bacterium was Pseudomonas aeruginosa (PA). Regardless of OM subtype, ≥ 80% of CNS and MRSA strains were resistant to penicillin (PC) and tetracycline (TC); isolated MRSA strains showed low sensitivity to other antibiotics, with 100% resistant to PC, TC, cefoxitin (CFT), and erythromycin (EM); and isolated PA showed low sensitivity to quinolone antibiotics, including ciprofloxacin (CIP) and levofloxacin (LFX), and to aminoglycosides. Bacterial species and antibiotic sensitivity did not change significantly over 5 years. The rate of detection of MRSA was higher in OME than in previous studies. As bacterial predominance and antibiotic sensitivity could change over time, continuous and periodic surveillance is necessary in guiding appropriate antibacterial therapy. © 2017 The Korean Academy of Medical Sciences.

Cost-Effectiveness of Antibiotic Prophylaxis Strategies for Transrectal Prostate Biopsy in an Era of Increasing Antimicrobial Resistance.

PubMed

Lee, Kyueun; Drekonja, Dimitri M; Enns, Eva A

2018-03-01

To determine the optimal antibiotic prophylaxis strategy for transrectal prostate biopsy (TRPB) as a function of the local antibiotic resistance profile. We developed a decision-analytic model to assess the cost-effectiveness of four antibiotic prophylaxis strategies: ciprofloxacin alone, ceftriaxone alone, ciprofloxacin and ceftriaxone in combination, and directed prophylaxis selection based on susceptibility testing. We used a payer's perspective and estimated the health care costs and quality-adjusted life-years (QALYs) associated with each strategy for a cohort of 66-year-old men undergoing TRPB. Costs and benefits were discounted at 3% annually. Base-case resistance prevalence was 29% to ciprofloxacin and 7% to ceftriaxone, reflecting susceptibility patterns observed at the Minneapolis Veterans Affairs Health Care System. Resistance levels were varied in sensitivity analysis. In the base case, single-agent prophylaxis strategies were dominated. Directed prophylaxis strategy was the optimal strategy at a willingness-to-pay threshold of $50,000/QALY gained. Relative to the directed prophylaxis strategy, the incremental cost-effectiveness ratio of the combination strategy was $123,333/QALY gained over the lifetime time horizon. In sensitivity analysis, single-agent prophylaxis strategies were preferred only at extreme levels of resistance. Directed or combination prophylaxis strategies were optimal for a wide range of resistance levels. Facilities using single-agent antibiotic prophylaxis strategies before TRPB should re-evaluate their strategies unless extremely low levels of antimicrobial resistance are documented. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Antimicrobial activity of lactobacillus strains against uropathogens.

PubMed

Shim, Yoon Hee; Lee, Seung Joo; Lee, Jung Won

2016-10-01

The use of lactobacillus probiotics has been proposed as an alternative to prophylactic antibiotics for preventing urinary tract infection (UTI) in the era of antibiotic resistance. In this study, the antimicrobial activity of lactobacillus strains against uropathogens, was evaluated and compared with that of antibiotics. To evaluate inhibitory activities of lactobacilli against uropathogens, six lactobacillus strains (L. gasseri, L. rhamnosus, L. acidophilus, L. plantarum, L. paracasei, L. acidophilus) and four representative uropathogens of infantile UTI (extended-spectrum beta-lactamase [ESBL](-) Escherichia coli, ESBL(+) E. coli, Proteus vulgaris, Enterococcus fecalis) were selected. Lactobacillus strain in vitro inhibition of each uropathogen was evaluated on MRS agar well diffusion assay and compared with that of commercial antibiotic discs. Average inhibitory zone for each of the six lactobacillus strains against the four uropathogens showed slightly different but consistent inhibition (inhibitory zone diameter, 10.5-20.0 mm). This was different to that of the antibiotic discs, which had a wider range of inhibition (inhibitory zone diameter, <6.0-27.5 mm) depending on the uropathogen resistance pattern. The inhibitory zone of the six lactobacillus strains was between that of sensitive and resistant antibiotics (P < 0.05). Lactobacillus strains had similar moderate antimicrobial activities against uropathogens. Further research is needed to ascertain the strains with the best probiotic potential. © 2016 Japan Pediatric Society.

Detection of meca gene from methicillin resistant staphylococcus aureus isolates of north sumatera

NASA Astrophysics Data System (ADS)

Septiani Nasution, Gabriella; Suryanto, Dwi; Lia Kusumawati, R.

2018-03-01

Methicillin Resistant Staphylococcus aureus (MRSA) is a major pathogen associated with hospital-acquired infections (nosocomial infections). MRSA is a type of S. aureus resistant to the sub-group of beta-lactam antibiotics such as penicillin, cephalosporin, monobactam, and carbapenem. MRSA is resistant because of genetic changes caused by exposure to irrational antibiotic therapy. This study aimed to detect mecA gene in North Sumatra isolates of MRSA and to determine the pattern of antibiotic resistance in S.aureus isolates classified as MRSA by Vitek 2 Compact in the Central Public Hospital Haji Adam Malik, Medan. Samples were 40 isolates of S. aureus classified as MRSA obtained from clinical microbiology specimens. DNA isolation of the isolates was conducted by a method of freeze-thaw cycling. Amplification of mecA gene was done by PCR technique using specific primer for the gene. PCR products were visualized using mini-gel electrophoresis. The results showed that all MRSA isolates showed to have 533 bp band of mecA. Antibiotics test of Vitek 2 Compact showed that despite all isolates were resistant to beta-lactam antibiotics groups; the isolates showed multidrug resistant to other common antibiotics, such as aminoglycosides, macrolides, and fluoroquinolones. However, they were still sensitive to vancomycin (82.5% isolates), linezolid (97.5% isolates), and tigecycline (100% isolates).

Gas Plasma Pre-treatment Increases Antibiotic Sensitivity and Persister Eradication in Methicillin-Resistant Staphylococcus aureus

PubMed Central

Guo, Li; Xu, Ruobing; Zhao, Yiming; Liu, Dingxin; Liu, Zhijie; Wang, Xiaohua; Chen, Hailan; Kong, Michael G.

2018-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of serious nosocomial infections, and recurrent MRSA infections primarily result from the survival of persister cells after antibiotic treatment. Gas plasma, a novel source of ROS (reactive oxygen species) and RNS (reactive nitrogen species) generation, not only inactivates pathogenic microbes but also restore the sensitivity of MRSA to antibiotics. This study further found that sublethal treatment of MRSA with both plasma and plasma-activated saline increased the antibiotic sensitivity and promoted the eradication of persister cells by tetracycline, gentamycin, clindamycin, chloramphenicol, ciprofloxacin, rifampicin, and vancomycin. The short-lived ROS and RNS generated by plasma played a primary role in the process and induced the increase of many species of ROS and RNS in MRSA cells. Thus, our data indicated that the plasma treatment could promote the effects of many different classes of antibiotics and act as an antibiotic sensitizer for the treatment of antibiotic-resistant bacteria involved in infectious diseases. PMID:29628915

[Evaluation of antibiotic resistance of Escherichia coli in urinary tract infections in Primary Care Barbastro Sector (Huesca)].

PubMed

Betrán, Ana; Cortés, Ana Ma; López, Concepción

2015-10-01

Evaluate the resistance of community-uropathogen, Escherichia coli to several antibiotics in our health sector and deduce empirical treatment options. E. coli strains isolated from urine cultures of patients from Primary Care Barbastro Sector, between January 2011 and December 2013, were studied. The resistances rates for nine common antibiotics were determined, and differences in sensitivity were analyzed, comparing confidence intervals for proportions by the method of Wilson. E. coli was the most frequently isolated bacteria (61.08% of positive urine cultures sent from Primary Care). Overall, there has been an increase in resistance of E. coli isolates in all antimicrobials studied. Still, resistance has remained below 4% compared to fosfomycin and nitrofurantoin and below 10% in cephalosporins second and third generation. Resistance to amoxicillin-clavulanate has increased progressively reaching 21.5% in 2013; only this antibiotic has presented a statistically significant increase. The maximum levels of resistance (over 30%) were found in the antibiotics administered orally and often indicated in uncomplicated urinary tract infections: trimethoprim-sulfamethoxazole, ciprofloxacin and ampicillin. Update knowledge susceptibility patterns of microorganisms most commonly isolated in urine samples in each health area allows to choose the most suitable and effective treatments trough empirical knowledge.

The microbiological spectrum and antibiotic sensitivity profile of extubated silicone stents following dacryocystorhinostomy.

PubMed

Ali, Mohammad Javed; Manderwad, Guruprasad; Naik, Milind N

2013-10-01

We aim to report the microbiological spectrum of organisms cultured from extubated silicone stents after a dacryocystorhinostomy and their antibiotic sensitivity patterns. Prospective interventional study. 50 silicone stents of 50 consecutive patients who underwent either external or endonasal dacryocystorhinostomy were enrolled for the study. All the stents were retrieved under endoscopic guidance from the nasal cavity at 3 months following surgery. All the tubes were immediately inoculated onto blood agar, chocolate agar, brain-heart infusion broth, Saboraud's dextrose agar and potato dextrose agar. Data collected and analyzed include demographics, diagnosis, type of dacryocystorhinostomy and the microbiological profile. The culture results, organisms isolated and their antibiotic sensitivity were studied. The mean age of patients at the time of dacyrocystorhinostomy was 34.4 years. Bacterial growth was noted in 88% (44/50) of all the stents cultured, whereas 60% (30/50) grew fungi and 6% (3/50) showed sterile cultures. 48% (24/50) of the stents showed mixed bacterial and fungal isolates. Among the fungal isolates, Aspergillus species accounted for 66.6% (20/30) followed by Fusarium species, which were seen in 26.6% (8/30). Among the bacterial isolates, gram negative organisms were the most common seen in 54.5% (24/44) and the commonest species isolated was Pseudomonas aeruginosa from 27% (12/44) of the stents. Staphylococcus aureus was the commonest gram positive isolate accounting for 18% of all the bacterial isolates. Gram positive organisms were commonly sensitive to cephalosporins and vancomycin whereas gram negative organisms were sensitive to quinolones and aminoglycosides. The surgical success rate was 96% (48/50). Fungal isolates were cultured from significant number of stents retrieved following dacryocystorhinostomy. Gram negative organisms are more common as compared to the gram positive. The organisms isolated were not found to influence the success of dacryocystorhinostomy.

Relationship of Triamine-Biocide Tolerance of Salmonella enterica Serovar Senftenberg to Antimicrobial Susceptibility, Serum Resistance and Outer Membrane Proteins.

PubMed

Futoma-Kołoch, Bożena; Dudek, Bartłomiej; Kapczyńska, Katarzyna; Krzyżewska, Eva; Wańczyk, Martyna; Korzekwa, Kamila; Rybka, Jacek; Klausa, Elżbieta; Bugla-Płoskońska, Gabriela

2017-07-11

A new emerging phenomenon is the association between the incorrect use of biocides in the process of disinfection in farms and the emergence of cross-resistance in Salmonella populations. Adaptation of the microorganisms to the sub-inhibitory concentrations of the disinfectants is not clear, but may result in an increase of sensitivity or resistance to antibiotics, depending on the biocide used and the challenged Salmonella serovar. Exposure of five Salmonella enterica subsp. enterica serovar Senftenberg ( S. Senftenberg) strains to triamine-containing disinfectant did not result in variants with resistance to antibiotics, but has changed their susceptibility to normal human serum (NHS). Three biocide variants developed reduced sensitivity to NHS in comparison to the sensitive parental strains, while two isolates lost their resistance to serum. For S. Senftenberg, which exhibited the highest triamine tolerance (6 × MIC) and intrinsic sensitivity to 22.5% and 45% NHS, a downregulation of flagellin and enolase has been demonstrated, which might suggest a lower adhesion and virulence of the bacteria. This is the first report demonstrating the influence of biocide tolerance on NHS resistance. In conclusion, there was a potential in S. Senftenberg to adjust to the conditions, where the biocide containing triamine was present. However, the adaptation did not result in the increase of antibiotic resistance, but manifested in changes within outer membrane proteins' patterns. The strategy of bacterial membrane proteins' analysis provides an opportunity to adjust the ways of infection treatments, especially when it is connected to the life-threating bacteremia caused by Salmonella species.

Relationship of Triamine-Biocide Tolerance of Salmonella enterica Serovar Senftenberg to Antimicrobial Susceptibility, Serum Resistance and Outer Membrane Proteins

PubMed Central

Futoma-Kołoch, Bożena; Dudek, Bartłomiej; Kapczyńska, Katarzyna; Wańczyk, Martyna; Korzekwa, Kamila; Rybka, Jacek; Klausa, Elżbieta; Bugla-Płoskońska, Gabriela

2017-01-01

A new emerging phenomenon is the association between the incorrect use of biocides in the process of disinfection in farms and the emergence of cross-resistance in Salmonella populations. Adaptation of the microorganisms to the sub-inhibitory concentrations of the disinfectants is not clear, but may result in an increase of sensitivity or resistance to antibiotics, depending on the biocide used and the challenged Salmonella serovar. Exposure of five Salmonella enterica subsp. enterica serovar Senftenberg (S. Senftenberg) strains to triamine-containing disinfectant did not result in variants with resistance to antibiotics, but has changed their susceptibility to normal human serum (NHS). Three biocide variants developed reduced sensitivity to NHS in comparison to the sensitive parental strains, while two isolates lost their resistance to serum. For S. Senftenberg, which exhibited the highest triamine tolerance (6 × MIC) and intrinsic sensitivity to 22.5% and 45% NHS, a downregulation of flagellin and enolase has been demonstrated, which might suggest a lower adhesion and virulence of the bacteria. This is the first report demonstrating the influence of biocide tolerance on NHS resistance. In conclusion, there was a potential in S. Senftenberg to adjust to the conditions, where the biocide containing triamine was present. However, the adaptation did not result in the increase of antibiotic resistance, but manifested in changes within outer membrane proteins’ patterns. The strategy of bacterial membrane proteins’ analysis provides an opportunity to adjust the ways of infection treatments, especially when it is connected to the life-threating bacteremia caused by Salmonella species. PMID:28696348

Antibiotic resistance patterns of community-acquired urinary tract infections in children with vesicoureteral reflux receiving prophylactic antibiotic therapy.

PubMed

Cheng, Chi-Hui; Tsai, Ming-Horng; Huang, Yhu-Chering; Su, Lin-Hui; Tsau, Yong-Kwei; Lin, Chi-Jen; Chiu, Cheng-Hsun; Lin, Tzou-Yien

2008-12-01

The goal was to examine bacterial antimicrobial resistance of recurrent urinary tract infections in children receiving antibiotic prophylaxis because of primary vesicoureteral reflux. We reviewed data retrospectively for children with documented vesicoureteral reflux in 2 hospitals during a 5-year follow-up period. The patients were receiving co-trimoxazole, cephalexin, or cefaclor prophylaxis or prophylaxis with a sequence of different antibiotics (alternative monotherapy). Demographic data, degree of vesicoureteral reflux, prophylactic antibiotics prescribed, and antibiotic sensitivity results of first urinary tract infections and breakthrough urinary tract infections were recorded. Three hundred twenty-four patients underwent antibiotic prophylaxis (109 with co-trimoxazole, 100 with cephalexin, 44 with cefaclor, and 71 with alternative monotherapy) in one hospital and 96 children underwent co-trimoxazole prophylaxis in the other hospital. Breakthrough urinary tract infections occurred in patients from both hospitals (20.4% and 25%, respectively). Escherichia coli infection was significantly less common in children receiving antibiotic prophylaxis, compared with their initial episodes of urinary tract infection, at both hospitals. Children receiving cephalosporin prophylaxis were more likely to have an extended-spectrum beta-lactamase-producing organism for breakthrough urinary tract infections, compared with children with co-trimoxazole prophylaxis. Antimicrobial susceptibilities to almost all antibiotics decreased with cephalosporin prophylaxis when recurrent urinary tract infections developed. The extent of decreased susceptibilities was also severe for prophylaxis with a sequence of different antibiotics. However, antimicrobial susceptibilities decreased minimally in co-trimoxazole prophylaxis groups. Children receiving cephalosporin prophylaxis are more likely to have extended-spectrum beta-lactamase-producing bacteria or multidrug-resistant uropathogens other than E coli for breakthrough urinary tract infections; therefore, these antibiotics are not appropriate for prophylactic use in patients with vesicoureteral reflux. Co-trimoxazole remains the preferred prophylactic agent for vesicoureteral reflux.

Molecular characterization, antibiotic resistance pattern and biofilm formation of Vibrio parahaemolyticus and V. cholerae isolated from crustaceans and humans.

PubMed

Ahmed, Heba A; El Bayomi, Rasha M; Hussein, Mohamed A; Khedr, Mariam H E; Abo Remela, Etab M; El-Ashram, Ahmed M M

2018-06-02

Human infection with pathogenic vibrios is associated with contaminated seafood consumption. In the present study, we examined 225 crustaceans collected from retail markets in Egypt. Stool samples from gastroenteritis patients were also examined. Bacteriological and molecular examinations revealed 34 (15.1%) V. parahaemolyticus and 2 (0.9%) V. cholerae from crustaceans, while V. parahaemolyticus isolates were identified in 3 (3%) of the human samples. The virulence-associated genes tdh and/or trh were detected in 5.9% and 100% of the crustacean and human samples, respectively, whereas the two V. cholerae isolates were positive for the ctx and hlyA genes. Antibiotic sensitivity revealed high resistance of the isolates to the used antibiotics and an average MAR index of 0.77. Biofilm formation at different temperatures indicated significantly higher biofilm formation at 37 °C and 25 °C compared with 4 °C. Frequent monitoring of seafood for Vibrio species and their antibiotic, molecular and biofilm characteristics is essential to improve seafood safety. Copyright © 2018 Elsevier B.V. All rights reserved.

Pattern of Antibiotic Prescription among Dentists in Iran

PubMed Central

Kakoei, Shahla; Raoof, Maryam; Baghaei, Fahimeh; Adhami, Shahrzad

2007-01-01

INTRODUCTION: This study examines the antibiotic prescription in dentists participated in 9th Congress of Iranian Association of Endodontists in Esfahan/2006. MATERIALS AND METHODS: A questionnaire for this cross sectional study was designed for evaluating the patterns of antibiotic prescription. It included some demographic information, clinical signs, and conditions in need for antibiotic and prophylactic prescription and their choices. Data was analyzed using Pearson’s Chi-square test. RESULTS: High percentage of responders prescribe antibiotic for fever (78.2%) and diffuse swelling (85.1%). However, some situations such as acute pulpitis, chronic periapical lesions and marginal gingivitis were irrationally prescribed. CONCLUSION: This study showed a fairly good pattern of antibiotic prescription but it was far from ideal. PMID:24348653

Resistance Patterns of Typhoid Fever in Children: A Longitudinal Community-Based Study.

PubMed

Vala, Snehal; Shah, Urvesh; Ahmad, Syed Amir; Scolnik, Dennis; Glatstein, Miguel

2016-01-01

Salmonella typhi and S. paratyphi are important causes of bacteremia in children, especially those from the developing world. There is a lack of standardized treatment protocols for such patients in the literature, and there are also reports of therapeutic failure related to resistance to commonly used antibiotics. We analyzed the epidemiological, clinical, and antimicrobiological sensitivity patterns of disease in patients diagnosed with blood culture-positive typhoid fever over a 6-month period in a tertiary-care pediatric hospital in western India. Data were retrospectively analyzed for all patients with Salmonella isolates on blood culture between January 1 and June 30, 2011 at the Synergy Neonatal and Pediatric Hospital. Susceptibility of isolates to antimicrobials and minimum inhibitory concentrations were determined. Demographic data, symptoms and signs, basic laboratory results, treatment courses, and clinical outcomes were collected from clinical charts. All of the 61 isolates of S. typhi were sensitive to cefepime (fourth-generation cephalosporin), 96% to third-generation cephalosporins, and 95% to quinolones. There was intermediate sensitivity to ampicillin (92%) and chloramphenicol (80%). Notably, azithromycin resistance was observed in 63% of isolates. All patients ultimately made full recoveries. There is an urgent need for large scale, community-based clinical trials to evaluate the effectiveness of different antibiotics in enteric fever. Our antimicrobial susceptibility data suggest that quinolones and third-generation cephalosporins should be used as first-line antimicrobials in enteric fever. Although fourth-generation cephalosporins are useful, we feel their use should be restricted to complicated or resistant cases.

Lipid Content of Antibiotic-Resistant and -Sensitive Strains of Serratia marcescens

PubMed Central

Chang, Chuan-Yi; Molar, Roger E.; Tsang, Joseph C.

1972-01-01

The lipid content of antibiotic-resistant, nonpigmented strain (Bizio) and antibiotic-sensitive, pigmented strain (08) of Serratia marcescens was studied. The resistant strain contains at least three times more total extractable lipid and phospholipid than the sensitive strain. Lysophosphatidylethanolamine, phosphatidylserine, lecithin, phosphatidylglycerol, phosphatidylethanolamine, and polyglycerolphosphatide were identified in the phospholipid fractions of both strains. Images PMID:4568257

Bacterial isolates and their antimicrobial susceptibility patterns among pediatric patients with urinary tract infections.

PubMed

Ayelign, Birhanu; Abebe, Betelehem; Shibeshi, Adugna; Meshesha, Sosina; Shibabaw, Tewodros; Addis, Zelalem; Gelaw, Aschalew; Dagnew, Mulat

2018-01-01

Urinary tract infection is a common pediatric problem with the potential to produce long-term morbidity. Therefore, appropriate diagnosis and prompt treatment is required. However, studies about magnitude of uropathogenicity and antimicrobial resistance pattern of pediatric urinary tract infection (UTI) are lacking in resource limited countries including Ethiopia. This study was aimed to determine bacterial isolates, antimicrobial susceptibility pattern among pediatric patients with UTI. A cross- sectional study was conducted. Pathogenic bacterial isolates were identified by culture and biochemical methods following standard procedures. Antimicrobial susceptibility testing of the isolates for commonly used antibiotics was done using the standard disc diffusion method on Muller Hinton agar. Associations between dependent and independent variables were measured using chi-square test and within 95% confidence interval. P values <0.05 were considered as statistically significant. A total of 310 pediatric patients were included in the study, and 82 (26.45%) bacterial isolates were detected. Gram- negative bacteria were predominant etiologic agents of UTI in this study. E. coli was the most frequently occurring pathogen (n=45; 54.88%) followed by S. aureus and P.aeruginosa (n=8; 9.75% for both), P. vulgaris , P.aeruginosa (n=4; 4.88%, for both) and Enterococcus species (n=3; 3.66%). All K. pneumoniae , P. mirabilis , and K. ozanae straines were 100% resistance to ampicillin, followed by P. aeruginosa (87.5%) and E. coli (69%). While all Gram- positive bacterial isolates were 100% sensitive to ciprofloxacin. Malnutrition, history of catherization and previous history of UTI were independently associated with UTI (p=0.000). There was a high prevalence of uropathogenic bacteria and drug resistance particularly to ampicillin (72%) and tetracycline (37.80%). This condition indicates that antibiotic selection should be based on knowledge of the local prevalence of bacterial organisms and antibiotic sensitivities rather than empirical treatment.

Antibiotic resistance pattern and empirical therapy for urinary tract infections in children.

PubMed

Al-Harthi, Abdulla A; Al-Fifi, Suliman H

2008-06-01

To study the type of bacterial pathogen causing urinary tract infection in children at Aseer Central Hospital, southwestern Saudi Arabia, and their antimicrobial resistance patterns. A retrospective study of all the urine cultures carried out on children in the period from January 2003 to December 2006, for a total of 4 years were reviewed at the bacteriology laboratory, Aseer Central Hospital, southwestern region of Saudi Arabia. Their antimicrobial resistances as well as sensitivities were also analyzed. A total of 464 urine cultures were identified. Escherichia coli constitutes the most common pathogen isolated (37.3%), followed by Klebsiella (16.4%) and Pseudomonas species (15.7%). In general, there was a significant increase in the resistance rates of different bacterial pathogens to different antibiotics. In spite of an increase in the resistance rates of bacterial pathogens causing UTI, ceftriaxone, imipenem, and to some extent Azactam are appropriate for initial empirical intravenous therapy in UTI. In patients with uncomplicated UTI not requiring hospitalization, Nalidixic acid, and Nitrofurantoin can be used as oral treatment.

Classification of Antibiotic Resistance Patterns of Indicator Bacteria by Discriminant Analysis: Use in Predicting the Source of Fecal Contamination in Subtropical Waters

PubMed Central

Harwood, Valerie J.; Whitlock, John; Withington, Victoria

2000-01-01

The antibiotic resistance patterns of fecal streptococci and fecal coliforms isolated from domestic wastewater and animal feces were determined using a battery of antibiotics (amoxicillin, ampicillin, cephalothin, chlortetracycline, oxytetracycline, tetracycline, erythromycin, streptomycin, and vancomycin) at four concentrations each. The sources of animal feces included wild birds, cattle, chickens, dogs, pigs, and raccoons. Antibiotic resistance patterns of fecal streptococci and fecal coliforms from known sources were grouped into two separate databases, and discriminant analysis of these patterns was used to establish the relationship between the antibiotic resistance patterns and the bacterial source. The fecal streptococcus and fecal coliform databases classified isolates from known sources with similar accuracies. The average rate of correct classification for the fecal streptococcus database was 62.3%, and that for the fecal coliform database was 63.9%. The sources of fecal streptococci and fecal coliforms isolated from surface waters were identified by discriminant analysis of their antibiotic resistance patterns. Both databases identified the source of indicator bacteria isolated from surface waters directly impacted by septic tank discharges as human. At sample sites selected for relatively low anthropogenic impact, the dominant sources of indicator bacteria were identified as various animals. The antibiotic resistance analysis technique promises to be a useful tool in assessing sources of fecal contamination in subtropical waters, such as those in Florida. PMID:10966379

Influence of regular reporting on local Pseudomonas aeruginosa and Acinetobacter spp. sensitivity to antibiotics on consumption of antibiotics and resistance patterns.

PubMed

Djordjevic, Z M; Folic, M M; Jankovic, S M

2017-10-01

Regular surveillance of antimicrobial resistance is an important component of multifaceted interventions directed at the problem with resistance of bacteria causing healthcare-associated infections (HAIs) in intensive care units (ICUs). Our aim was to analyse antimicrobial consumption and resistance among isolates of Pseudomonas aeruginosa and Acinetobacter spp. causing HAIs, before and after the introduction of mandatory reporting of resistance patterns to prescribers. A retrospective observational study was conducted between January 2011 and December 2015, at an interdisciplinary ICU of the Clinical Centre Kragujevac, Serbia. The intervention consisted of continuous resistance monitoring of all bacterial isolates from ICU patients and biannual reporting of results per isolate to prescribers across the hospital. Both utilization of antibiotics and density of resistant isolates of P. aeruginosa and Acinetobacter spp. were followed within the ICU. Resistance densities of P. aeruginosa to all tested antimicrobials were lower in 2015, in comparison with 2011. Although isolates of Acinetobacter spp. had lower resistance density in 2015 than in 2011 to the majority of investigated antibiotics, a statistically significant decrease was noted only for piperacillin/tazobactam. Statistically significant decreasing trends of consumption were recorded for third-generation cephalosporins, aminoglycosides and fluoroquinolones, whereas for the piperacillin/tazobactam, ampicillin/sulbactam and carbapenems, utilization trends were decreasing, but without statistical significance. In the same period, increasing trends of consumption were observed for tigecycline and colistin. Regular monitoring of resistance of bacterial isolates in ICUs and reporting of summary results to prescribers may lead to a significant decrease in utilization of some antibiotics and slow restoration of P. aeruginosa and Acinetobacter spp. susceptibility. © 2017 John Wiley & Sons Ltd.

Antibiotic Prescribing Patterns in Outpatient Emergency Clinics at Queen Rania Al Abdullah II Children's Hospital, Jordan, 2013.

PubMed

Al-Niemat, Sahar I; Aljbouri, Tareq M; Goussous, Lana S; Efaishat, Rania A; Salah, Rehab K

2014-07-01

To investigate antibiotics prescribing patterns in the outpatient pediatric emergency clinic at Queen Rania Al Abdullah II Children's Hospital at Royal Medical Services in Amman, Jordan. The data was collected from the emergency pharmacy over the period of a -five consecutive months. The methodology recommended by the World Health Organization for investigating drug use in a health facility was followed. The study measures the percentage of encounter with a prescribed antibiotic and the percentage share of each antibiotic category. The distribution of diagnostic categories that accounted for all antibiotics being prescribed and the distribution of each antibiotic being prescribed for upper respiratory tract infections (URTIs) were also measured. Antibiotic prescribing was frequent during pediatric visits to the outpatient pediatric emergency clinic resulting in a high percentage of encounters (85%) when compared to appropriate. Emergency physicians continue to frequently prescribe broad spectrum antibiotics which accounted for approximately (60%) of the total prescribed antibiotics and (83%) of prescribed antibiotics for upper respiratory tract infections and macrolides (primarily azithromycin) were the leading class among them. Our results showed high consumption of antibiotics by emergency department pediatricians which highlight the importance for interventions to promote rational and judicious prescribing. An insight into factors influencing antibiotics prescribing patterns by military prescribers is required.

The enhanced effects of antibiotics irradiated of extremely high frequency electromagnetic field on Escherichia coli growth properties.

PubMed

Torgomyan, Heghine; Trchounian, Armen

2015-01-01

The effects of extremely high frequency electromagnetic irradiation and antibiotics on Escherichia coli can create new opportunities for applications in different areas—medicine, agriculture, and food industry. Previously was shown that irradiated bacterial sensitivity against antibiotics was changed. In this work, it was presented the results that irradiation of antibiotics and then adding into growth medium was more effective compared with non-irradiated antibiotics bactericidal action. The selected antibiotics (tetracycline, kanamycin, chloramphenicol, and ceftriaxone) were from different groups. Antibiotics irradiation was performed with low intensity 53 GHz frequency during 1 h. The E. coli growth properties—lag-phase duration and specific growth rate—were markedly changed. Enhanced bacterial sensitivity to irradiated antibiotics is similar to the effects of antibiotics of higher concentrations.

Pattern of infection, therapy, outcome and risk stratification of patients with febrile neutropenia in a tertiary care oncology hospital in India.

PubMed

Noronha, V; Joshi, A; Patil, V M; Bhosale, B; Muddu, V K; Banavali, S; Kelkar, R; Prabhash, K

2014-01-01

Indian febrile neutropenia (FN) data are limited, especially in adult solid tumor patients. The aim was to study patterns of presentation, source of infection, management and outcome and to evaluate the factors which may correlate with outcome. A retrospective analysis of prospective data of FN patients at a tertiary care oncology teaching hospital in India between 2007 and 2012. A standardized form was filled for each patient. Patient management was at the discretion of the treating physician. Multinational Association for Supportive Care in Cancer (MASCC) score was retrospectively calculated. Failure of therapy was defined as death, organ failure, shifting from outpatient to inpatient or requirement of intensive care support. SPSS version 16 was used for analysis. A total of 388 FN episodes were included: 256 in hematolymphoid and 132 in solid tumor patients. 156 episodes were high-risk by MASCC score. Focus of infection was clinical in 45% and radiologic in 16%. Blood cultures were positive in 18% cases, most commonly Gram-negative organisms (72%). 93% patients were treated with an antibiotic combination of third-generation cephalosporin/beta-lactamase inhibitor, with aminoglycoside or fluoroquinolone. Antibiotic sensitivity to ceftriaxone was low at 38% while sensitivity to cefoperazone/sulbactam and piperacillin/tazobactam ranged between 50% and 55% and for carbapenems 75%. Failure of therapy occurred in 156 episodes, most commonly due to the need for second line antibiotics. Mortality was 5.5%. On univariate analysis, MASCC score, age, type of malignancy, prophylactic growth factors, presence of focus of infection, hemoglobin and nadir platelet count correlated with FN complications. Gram-negative bacteremia continues to be the predominant cause of FN in our setup.

Acute Bacterial Prostatitis: Diagnosis and Management.

PubMed

Coker, Timothy J; Dierfeldt, Daniel M

2016-01-15

Acute bacterial prostatitis is an acute infection of the prostate gland that causes pelvic pain and urinary tract symptoms, such as dysuria, urinary frequency, and urinary retention, and may lead to systemic symptoms, such as fevers, chills, nausea, emesis, and malaise. Although the true incidence is unknown, acute bacterial prostatitis is estimated to comprise approximately 10% of all cases of prostatitis. Most acute bacterial prostatitis infections are community acquired, but some occur after transurethral manipulation procedures, such as urethral catheterization and cystoscopy, or after transrectal prostate biopsy. The physical examination should include abdominal, genital, and digital rectal examination to assess for a tender, enlarged, or boggy prostate. Diagnosis is predominantly made based on history and physical examination, but may be aided by urinalysis. Urine cultures should be obtained in all patients who are suspected of having acute bacterial prostatitis to determine the responsible bacteria and its antibiotic sensitivity pattern. Additional laboratory studies can be obtained based on risk factors and severity of illness. Radiography is typically unnecessary. Most patients can be treated as outpatients with oral antibiotics and supportive measures. Hospitalization and broad-spectrum intravenous antibiotics should be considered in patients who are systemically ill, unable to voluntarily urinate, unable to tolerate oral intake, or have risk factors for antibiotic resistance. Typical antibiotic regimens include ceftriaxone and doxycycline, ciprofloxacin, and piperacillin/tazobactam. The risk of nosocomial bacterial prostatitis can be reduced by using antibiotics, such as ciprofloxacin, before transrectal prostate biopsy.

An Insight into Antibiotic Resistance to Bacterial Infection in Chronic Liver Disease.

PubMed

Jain, Mayank; Varghese, Joy; Michael, Tom; Kedarishetty, Chandan Kumar; G, Balajee; Swaminathan, Subramanian; Venkataraman, Jayanthi

2017-12-01

End stage liver disease leads to immune dysfunction which predisposes to infection. There has been a rise in antibiotic resistant infections in these patients. There is scanty data f from India or idea regarding the same. The present study was undertaken to determine the type of infection acquired and the prevalence of antibiotic resistant infections in cirrhotic patients at a tertiary referral center in South India. In this retrospective study, all consecutive cirrhotic patients hospitalized between 2011 and 2013 with a microbiologically-documented infection were enrolled. Details of previous admission and antibiotics if received were noted. In culture positive infections, the source of infection (ascites, skin, respiratory tract: sputum/endotracheal tube aspirate, pleural fluid; urine and blood) and microorganisms isolated and their antibiotic susceptibility was noted. A total of 92 patients had 240 culture positive samples in the study period. Majority were Klebseilla followed by Escherichia coli and Enterococcus in nosocomial and health care associated infections. However, Enteroccocus was followed by E. coli and Klebsiella in community acquired infections. The antibiotic sensitivity pattern was analyzed for the major causative organisms such as E. coli , Klebsiella and Enterococcus . Most common resistant strains were extended spectrum beta lactamase producing enterobacteriacae (ESBL) followed by carbapenemase producing Klebsiella and methicillin resistant Staphylococcus aureus . Noscomial infection is the most common type, with Klebsiella and E. coli and there is significant rise in ESBL producing organism.

Lactobacillus farciminis MD, a newer strain with potential for bacteriocin and antibiotic assay.

PubMed

Halami, P M; Chandrashekar, A; Nand, K

2000-03-01

A native isolate Lactobacillus farciminis MD isolated from fermenting mushroom exhibited a high degree of sensitivity to the majority of the bacteriocins produced by strains of lactobacilli, leuconostoc and pediococci. Also, the efficacy of Lact. farciminis MD as a sensitive strain for antibiotic assay was established against different antibiotics including ampicillin, cefazoline, chloramphenicol and nitrofurantoin at concentrations of 30 microg each, showing an inhibition zone of 30 mm diameter. The high degree of sensitivity towards bacteriocins and antibiotics provide potential for the exploitation of Lact. farciminis MD in establishing very well-defined bacteriocin producers.

Antibiotic resistance patterns and genetic relatedness of Enterococcus faecalis and Enterococcus faecium isolated from military working dogs in Korea.

PubMed

Bang, Kiman; An, Jae-Uk; Kim, Woohyun; Dong, Hee-Jin; Kim, Junhyung; Cho, Seongbeom

2017-06-30

Enterococcus spp. are normally present in the gastrointestinal tracts of animals and humans, but can cause opportunistic infections that can be transmitted to other animals or humans with integrated antibiotic resistance. To investigate if this is a potential risk in military working dogs (MWDs), we analyzed antibiotic resistance patterns and genetic relatedness of Enterococcus spp. isolated from fecal samples of MWDs of four different age groups. Isolation rates of Enterococcus spp., Enterococcus ( E. ) faecalis , and E. faecium , were 87.7% (57/65), 59.6% (34/57), and 56.1% (32/57), respectively, as determined by bacterial culture and multiplex PCR. The isolation rate of E. faecalis gradually decreased with age (puppy, 100%; adolescent, 91.7%; adult, 36.4%; and senior, 14.3%). Rates of resistance to the antibiotics ciprofloxacin, gentamicin, streptomycin, sulfamethoxazole/trimethoprim, imipenem, and kanamycin among Enterococcus spp. increased in adolescents and adults and decreased in senior dogs, with some isolates having three different antibiotic resistance patterns. There were indistinguishable pulsed-field gel electrophoresis patterns among the age groups. The results suggest that Enterococcus is horizontally transferred, regardless of age. As such, periodic surveillance studies should be undertaken to monitor changes in antibiotic resistance, which may necessitate modification of antibiotic regimens to manage antibiotic resistance transmission.

Antibiotic Prescription, Organisms and its Resistance Pattern in Patients Admitted to Respiratory ICU with Respiratory Infection in Mysuru.

PubMed

Mahendra, M; Jayaraj, B S; Lokesh, K S; Chaya, S K; Veerapaneni, Vivek Vardhan; Limaye, Sneha; Dhar, Raja; Swarnakar, Rajesh; Ambalkar, Shrikant; Mahesh, P A

2018-04-01

Respiratory infections account for significant morbidity, mortality and expenses to patients getting admitted to ICU. Antibiotic resistance is a major worldwide concern in ICU, including India. It is important to know the antibiotic prescribing pattern in ICU, organisms and its resistance pattern as there is sparse data on Indian ICUs. We conducted a prospective study from August 2015 to February 2016. All patients getting admitted to RICU with respiratory infection who were treated with antibiotics were included into study. Demographic details, comorbidities, Clinco-pathological score (CPI) on day1 and 2 of admission, duration of ICU admission, number of antibiotics used, antibiotic prescription, antimicrobial resistance pattern of patients were collected using APRISE questionnaire. During study period 352 patients were screened and 303 patients were included into study. Mean age was 56.05±16.37 and 190 (62.70%) were men. Most common diagnosis was Pneumonia (66%). Piperacillin-tazobactam was most common empirical antibiotic used. We found 60% resistance to piperacillin-tazobactam. Acinetobacter baumanii was the most common organism isolated (29.2%) and was highly resistant to Carbapenem (60%). Klebsiella pneumoniae was resistant to Amikacin (45%), piperacillin (55%) and Ceftazidime (50%). Piperacillin-tazobactam was the most common antibiotic prescribed to patients with respiratory infection admitted to ICU. More than half of patients (60%) had resistance to the empirical antibiotic used in our ICU, highlighting the need for antibiogram for each ICU. Thirty six percent of patient had prior antibiotic use and had mainly gram negative organisms with high resistance to commonly used antibiotics.

Trends and patterns of antibiotic consumption in China's tertiary hospitals: Based on a 5 year surveillance with sales records, 2011-2015.

PubMed

Wushouer, Haishaerjiang; Tian, Ye; Guan, Xiao-Dong; Han, Sheng; Shi, Lu-Wen

2017-01-01

The consumption of antibiotics is a major driver in the development of antimicrobial resistance. This study aims to identify the trends and patterns of the total antibiotic consumption in China's tertiary hospitals from 2011 to 2015 by retrospectively analyzing aggregated monthly surveillance data on antibiotic sales made to 468 hospitals from 28 provinces. Antibiotic consumption was expressed in DDD per 1,000 inhabitants per day (DID). We compared population weighted antibiotic consumption patterns in China with European countries using indicators from the European Surveillance of Antimicrobial Consumption (ESAC). Total antibiotic consumption, including all the specific antibiotic class except for aminoglycoside antibacterials, were significantly increased during the study period from an average of 7.97 DID in 2011 to 10.08 DID in 2015. In 2015, the eastern regions of China consumed the most antibiotics using population denominator while the western regions consumed the most using inpatient denominator. Cephalosporins accounted for 28.6% of total DID, followed by beta-lactam-beta-lactamase inhibitor combinations (20.0%), macrolides (17.4%), and fluoroquinolones (10.5%). Antibiotic in parenteral form accounted for nearly half of all antibiotics. Although over the past few years major efforts had been made to reduce the risks of excessive antibiotic use through antibiotic stewardship, total antibiotic consumption showed a significant upward trend during the study period. A consistent preference for cephalosporins, macrolides, beta-lactam-beta-lactamase inhibitor combinations, as well as parenteral preparations was observed.

Toxicological impacts of antibiotics on aquatic micro-organisms: A mini-review.

PubMed

Välitalo, Pia; Kruglova, Antonina; Mikola, Anna; Vahala, Riku

2017-05-01

Antibiotics are found globally in the environment at trace levels due to their extensive consumption, which raises concerns about the effects they can have on non-target organisms, especially environmental micro-organisms. So far the majority of studies have focused on different aspects of antibiotic resistance or on analyzing the occurrence, fate, and removal of antibiotics from hospital and municipal wastewaters. Little attention has been paid to ecotoxicological effects of antibiotics on aquatic micro-organisms although they play a critical role in most ecosystems and they are potentially sensitive to these substances. Here we review the current state of research on the toxicological impacts of antibiotics to aquatic micro-organisms, including proteobacteria, cyanobacteria, algae and bacteria commonly present in biological wastewater treatment processes. We focus on antibiotics that are poorly removed during wastewater treatment and thus end up in surface waters. We critically discuss and compare the available analytical methods and test organisms based on effect concentrations and identify the knowledge gaps and future challenges. We conclude that, in general, cyanobacteria and ammonium oxidizing bacteria are the most sensitive micro-organisms to antibiotics. It is important to include chronic tests in ecotoxicological assessment, because acute tests are not always appropriate in case of low sensitivity (for example for proteobacteria). However, the issue of rapid development of antibiotic resistance should be regarded in chronic testing. Furthermore, the application of other species of bacteria and endpoints should be considered in the future, not forgetting the mixture effect and bacterial community studies. Due to differences in the sensitivity of different test organisms to individual antibiotic substances, the application of several bioassays with varying test organisms would provide more comprehensive data for the risk assessment of antibiotics. Regardless of the growing concerns related to antibiotics in the environment, there are still evident knowledge gaps related to antibiotics, as there is only limited or no ecotoxicological data on many potentially harmful antibiotics. Copyright © 2017 Elsevier GmbH. All rights reserved.

Comparing the sensitivity of chlorophytes, cyanobacteria, and diatoms to major-use antibiotics.

PubMed

Guo, Jiahua; Selby, Katherine; Boxall, Alistair B A

2016-10-01

The occurrence of antibiotic residues in the aquatic environment is an emerging concern. In contrast to daphnia and fish, algae are known to be particularly sensitive to antibiotic exposure. However, to date, a systematic evaluation of the sensitivity of different algal species to antibiotics has not been performed. The aim of the present study was therefore to explore the sensitivity of a battery of algal species toward antibiotic exposures. The present study investigated the growth inhibition effects of 3 major-use antibiotics, tylosin, lincomycin, and trimethoprim, on 7 algal species from the chlorophyte, cyanobacteria, and diatom groups. Based on median effective concentration (EC50) values, cyanobacteria (EC50 = 0.095-0.13 μmol/L) were found to be the most sensitive group to lincomycin followed by chlorophytes (EC50 = 7.36-225.73 μmol/L) and diatoms (EC50 > 225.73 μmol/L). Cyanobacteria were also the most sensitive group to tylosin (EC50 = 0.09-0.092 μmol/L), but, for this compound, diatoms (EC50 = 1.33-5.7 μmol/L) were more sensitive than chlorophytes (EC50 = 4.14-81.2 μmol/L). Diatoms were most sensitive to trimethoprim (EC50 = 7.36-74.61 μmol/L), followed by cyanobacteria (EC50 = 315.78-344.45 μmol/L), and chlorophytes (EC50 > 344.45 μmol/L) for trimethoprim. Although these results partly support the current approach to regulatory environmental risk assessment (whereby cyanobacterial species are recommended for use with antibiotic compounds), they indicate that for some antibiotics this group might not be the most appropriate test organism. It is therefore suggested that environmental risk assessments consider data on 3 algal groups (chlorophytes, cyanobacteria, and diatoms) and use test species from these groups, which are consistently found to be the most sensitive (Pseudokirchneriella subcapitata, Anabaena flos-aquae, and Navicula pelliculosa). Environ Toxicol Chem 2016;35:2587-2596. © 2016 SETAC. © 2016 SETAC.

Studies on Early Allergic Sensitization in the Lithuanian Birth Cohort

PubMed Central

Dubakiene, Ruta; Rudzeviciene, Odilija; Butiene, Indre; Sezaite, Indre; Petronyte, Malvina; Vaicekauskaite, Dalia; Zvirbliene, Aurelija

2012-01-01

Cohort studies are of great importance in defining the mechanism responsible for the development of allergy-associated diseases, such as atopic dermatitis, allergic asthma, and allergic rhinoconjunctivitis. Although these disorders share genetic and environmental risk factors, it is still under debate whether they are linked or develop sequentially along an atopic pathway. The current study was aimed to determine the pattern of allergy sensitization in the Lithuanian birth cohort “Alergemol” (n = 1558) established as a part of the multicenter European birth cohort “EuroPrevall”. Early sensitization to food allergens in the “Alergemol” birth cohort was analysed. The analysis revealed 1.3% and 2.8% of symptomatic-sensitized subjects at 6 and 12 months of age, respectively. The sensitization pattern in response to different allergens in the group of infants with food allergy symptoms was studied using allergological methods in vivo and in vitro. The impact of maternal and environmental risk factors on the early development of food allergy in at 6 and 12 months of age was evaluated. Our data showed that maternal diet, diseases, the use of antibiotics, and tobacco smoke during pregnancy had no significant impact on the early sensitization to food allergens. However, infants of atopic mothers were significantly more often sensitized to egg as compared to the infants of nonatopic mothers. PMID:22606067

Incidence of multidrug resistant Vibrio parahaemolyticus isolated from Ponnani, South India.

PubMed

Reyhanath, Pilakka Veettil; Kutty, Ranjeet

2014-04-01

The prevalence of Vibrio parahaemolyticus has been reported from Ponnani earlier, however incidence of multidrug resistant strains have been encountered recently in clinical laboratories. The source for such strains and their presence in this major fish landing centre has been investigated. Antibiotic sensitivity tests on isolates of V. parahaemolyticus isolated from three different substrates were conducted following disc diffusion method. Populations of V. parahaemolyticus (cfu/ml) were relatively high in sediment samples (7.67 ± 2.08), compared to shrimp (5.33 ±1.53) and water samples (3.67 ± 1.15). V. parahaemolyticus isolated from water showed relatively higher antibiotic resistance pattern compared to other two groups. The highest incidence of antibiotic resistance was recorded against cephalothin and nitrofurantonine; the lowest was against tobramycin, piperacillin and amikacin. Maximum multiple drug resistant (MDR) strains were encountered from water samples followed by shrimps. Results emerging from the present study clearly showed that Ponnani has a fairly good population of antibiotic resistant strains of V. parahaemolyticus. The present study provides an insight on the microbial population of V. parahaemolyticus in Ponnani harbour and warrants the need to develop control measures to reduce incidences of post-harvest contamination of seafood.

Practice variation on use of antibiotics: An international survey among pediatric urologists.

PubMed

Kim, Jin K; Chua, Michael E; Ming, Jessica M; Braga, Luis H; Smith, Grahame H H; Driver, Christopher; Koyle, Martin A

2018-05-19

Although there is abundance in literature focusing on the use of prophylactic antibiotics for adult urological procedures, the evidence for using antibiotics following common pediatric urological procedures is limited with no specific guidelines for use. Consequently, current practices on antibiotic usage for common interventions may be variable among practicing pediatric urologists, lacking evidence-based support. The aim was to evaluate the current practice pattern on antibiotic usage for common interventions amongst pediatric urologists (PU) practicing in four English-speaking sectors of the world. An anonymous survey of five scenarios with multiple choice options was disseminated to all active practicing members of the Pediatric Urologist of Canada (PUC) and Society of Pediatric Urology of Australia and New Zealand (SPUNZA), as well as all those attending the 2016 British Association of Pediatric Urology (BAPU) and 2017 American Association of Pediatric Urology (AAPU) meetings. The response for each scenario was summarized for overall practice pattern variation and the pattern for each sector was compared using the Fisher exact test. A total of 126 respondents completed the survey (68.5% response rate) with at least a 65% response rate for each of the four sectors. The majority of respondents do not use antibiotics for indwelling urethral (46.8%) and suprapubic catheters (53.4%); however, they do give antibiotics for J-J stent placement (65.1%) and hypospadias surgery (84.9%), and use antibiotics after hypospadias surgery where catheters or stents are left indwelling (80.9%, 84.2%, respectively). Among those surveyed, the PUC members and AAPU PU demonstrated similar practice patterns which often significantly differed from that of SPUNZA members and BAPU attendees. Specifically, a significantly larger proportion of the North American pediatric urologists do not use antibiotics for common procedures compared with Australia, New Zealand, and the UK (Table). In the absence of prospective studies in antibiotic use for pediatric patients to guide clinicians, there is a clear variability among sectors in the use of antibiotics for most clinical scenarios investigated. With increasing resistance patterns and possible adverse effects of antibiotics, it is important that the international pediatric urology community engage in discussions and collaborations to address this issue. Practice patterns in antibiotic usage amongst PU varies widely, some of which may be associated with their local "culture." There is a need to understand these differences and begin to standardize treatment in the hopes of increasing appropriate use of antibiotics internationally. Copyright © 2018 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Role of Antibiosis in Competition of Erwinia Strains in Potato Infection Courts

PubMed Central

Axelrood, Paige E.; Rella, Manuela; Schroth, Milton N.

1988-01-01

Erwinia carotovora subsp. betavasculorum strains produced a bactericidal antibiotic in vitro that inhibited a wide spectrum of gram-negative and gram-positive bacteria. The optimum temperature for production was 24°C, and the addition of glycerol to culture media enhanced antibiotic production. Antibiotic production by these strains in the infection court of potato was the principal determinant enabling it to gain ascendancy over competing antibiotic-sensitive Erwinia carotovora subsp. carotovora strains. There was a complete correlation between antibiotic production by E. carotovora subsp. betavasculorum in vitro and inhibition of competing E. carotovora subsp. carotovora strains in planta. Inhibition of the latter by the former was apparent after 10 h of incubation in potato tuber wounds. Population densities of sensitive E. carotovora subsp. carotovora strains in mixed potato tuber infections with E. carotovora subsp. betavasculorum were approximately 106-fold lower after 48 h of incubation than in corresponding single sensitive strain infections. E. carotovora subsp. carotovora were not inhibited in tuber infections that were incubated anaerobically. This correlated with the absence of antibiotic production during anaerobic incubation in vitro. Antibiotic-resistant strains of E. carotovora subsp. carotovora were not inhibited in planta or in vitro by E. carotovora subsp. betavasculorum. Moreover, isogenic antibiotic-negative (Ant−) mutant E. carotovora subsp. betavasculorum strains were not inhibitory to sensitive E. carotovora subsp. carotovora strains in tuber infections. PMID:16347633

Bacterial cheating limits antibiotic resistance

NASA Astrophysics Data System (ADS)

Xiao Chao, Hui; Yurtsev, Eugene; Datta, Manoshi; Artemova, Tanya; Gore, Jeff

2012-02-01

The widespread use of antibiotics has led to the evolution of resistance in bacteria. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removing the antibiotic. The cooperative nature of this growth suggests that a cheater strain---which does not contribute to breaking down the antibiotic---may be able to take advantage of cells cooperatively inactivating the antibiotic. Here we find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We observe stable coexistence between the two strains and find that a simple model successfully explains the behavior as a function of antibiotic concentration and cell density. We anticipate that our results will provide insight into the evolutionary origin of phenotypic diversity and cooperative behaviors.

Trends and patterns of antibiotic consumption in Shanghai municipality, China: a 6 year surveillance with sales records, 2009-14.

PubMed

Lin, Hai; Dyar, Oliver James; Rosales-Klintz, Senia; Zhang, Jianzhong; Tomson, Göran; Hao, Mo; Stålsby Lundborg, Cecilia

2016-06-01

The objective of this study was to identify the trends and patterns of total antibiotic use in Shanghai from 2009 to 2014. Sales records were collected from a minimum of 160 hospitals and 241 primary healthcare settings and used as a proxy for consumption. Antibiotic sales expressed in DDD per 1000 inhabitants per day (DID) were calculated. We compared patterns of antibiotic use in the Shanghai municipality, populated by 24 million inhabitants, with European countries using indicators from the European Surveillance of Antimicrobial Consumption (ESAC). Total antibiotic use was highest at 25.9 DID in 2010, fell to 17.8 DID in 2012 and remained stable thereafter. The majority of this reduction occurred over 6 months in 2011. In 2014, two-thirds of the antibiotic sales were to hospitals (serving both inpatients and outpatients) and one-third to primary healthcare institutions. Cephalosporins accounted for 50.2% of total DID, followed by macrolides (18.2%), quinolones (16.0%) and penicillins (7.3%). A fifth of all antibiotics were used in parenteral form. We have successfully used aggregated sales data to monitor antibiotic usage across a large urban population over a 6 year period. A rapid, substantial and sustained reduction in antibiotic usage across the entire health system occurred. This coincided with several interventions across hierarchies in the health sector, including a national campaign. The patterns of antibiotic use indicate persistent preferences for cephalosporins, macrolides, quinolones and parenteral preparations. Further efforts are needed to investigate and improve the quality of antibiotic use. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Antibiotic Prescription, Organisms and its Resistance Pattern in Patients Admitted to Respiratory ICU with Respiratory Infection in Mysuru

PubMed Central

Mahendra, M; Jayaraj, BS; Lokesh, KS; Chaya, SK; Veerapaneni, Vivek Vardhan; Limaye, Sneha; Dhar, Raja; Swarnakar, Rajesh; Ambalkar, Shrikant; Mahesh, PA

2018-01-01

Aim of Study: Respiratory infections account for significant morbidity, mortality and expenses to patients getting admitted to ICU. Antibiotic resistance is a major worldwide concern in ICU, including India. It is important to know the antibiotic prescribing pattern in ICU, organisms and its resistance pattern as there is sparse data on Indian ICUs. Materials and Methods: We conducted a prospective study from August 2015 to February 2016. All patients getting admitted to RICU with respiratory infection who were treated with antibiotics were included into study. Demographic details, comorbidities, Clinco-pathological score (CPI) on day1 and 2 of admission, duration of ICU admission, number of antibiotics used, antibiotic prescription, antimicrobial resistance pattern of patients were collected using APRISE questionnaire. Results: During study period 352 patients were screened and 303 patients were included into study. Mean age was 56.05±16.37 and 190 (62.70%) were men. Most common diagnosis was Pneumonia (66%). Piperacillin-tazobactam was most common empirical antibiotic used. We found 60% resistance to piperacillin-tazobactam. Acinetobacter baumanii was the most common organism isolated (29.2%) and was highly resistant to Carbapenem (60%). Klebsiella pneumoniae was resistant to Amikacin (45%), piperacillin (55%) and Ceftazidime (50%). Conclusion: Piperacillin-tazobactam was the most common antibiotic prescribed to patients with respiratory infection admitted to ICU. More than half of patients (60%) had resistance to the empirical antibiotic used in our ICU, highlighting the need for antibiogram for each ICU. Thirty six percent of patient had prior antibiotic use and had mainly gram negative organisms with high resistance to commonly used antibiotics. PMID:29743760

Endodontic treatment-related antibiotic prescribing patterns of South African oral health professionals.

PubMed

Lalloo, R; Solanki, G; Ramphoma, K; Myburgh, N G

2017-11-01

To assess the antibiotic prescribing patterns of South African dentists for patients undergoing endodontic treatment. This study used data from 2013 health insurance claims submitted by South African oral health professionals to determine the antibiotic prescribing patterns related to endodontic treatment. A logistic regression model was used to test the fully adjusted statistical significance of the association between the exploratory variables (gender, age group, event type, abscess treatment, chronic health) and the dependent variable (antibiotic prescription). Odds ratios with 95% confidence intervals (CI) are reported, and a 95% CI excluding 1 was considered statistically significant. Almost 10% of endodontic treatments were prescribed an antibiotic. There were no significant differences in prescribing patterns by gender, age and chronic health status. Prescriptions were more common at the preparatory stage (9.4%) of root canal treatment compared to the therapy (4.7%) and canal filling (2%) stages. Patients who received apical surgery (OR = 2.28; 95% CI 1.38-3.76) and treatment of an abscess (OR = 2.57; 95% 1.82-3.63) had a significantly increased odds of being prescribed an antibiotic. Almost three-quarters of prescriptions were for narrow spectrum antibiotics. The frequency of antibiotic prescribing by South African dental practitioners for patients undergoing endodontic treatment is relatively low and predominantly involved narrow spectrum antibiotics. It, however, remains important that antibiotics are only prescribed when clinically essential, such as when there are obvious systemic effects. These include fever above 37 degrees, malaise, lymphadenopathy, trismus, increase swelling, cellulitis, osteomyelitis and persistent infection. The wider dissemination and adherence to clear evidence-based prescribing guidelines for antibiotics in this clinical area are important. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

[Sensitivity of microbial associations of periodontal lesions to antibacterial agents].

PubMed

Makeeva, I M; Daurova, F Yu; Byakova, S F; Ippolitov, E V; Gostev, M S; Polikushina, A O; Shubin, E V

2016-01-01

The aim of the study was the development of approaches to improve the effectiveness of antibiotic therapy in dental practice on the basis of determining the sensitivity of pathogenic microorganisms to antibiotics of different groups. The study included determination of the sensitivity of the microbial complexes from wound exudate of periodontal pocket and apical abscess to macrolides, quinolones, penicillins, lincosamides and 5-nitroimidazole. A survey of dentists and dental clinics patients to identify the cause and frequency of use of antibiotics and to identify possible adverse reactions was also conducted. Dentists prefer macrolide antibiotics, protected penicillins, and fluoroquinolone combined with 5-nitroimidazole. All patients have taken antibiotics themselves at least once a year. Microbial complexes in patients with acute and exacerbated apical periodontitis in 79% of cases are susceptible to amoxicillin/clavulanic acid, to azithromycin - 52%, lincomycin - 36%, 5-nitroimidazole - 68%, ciprofloxacin - 73.7%. In patients with apical abscess high rates of resistance of microbial complexes to all types of antibiotics was revealed (33% for lincomycin 76,1% for ciprofloxacin, 28,6% for 5-nitroimidazole). Patients with moderate to severe periodontitis in 90.5% are sensitive to amoxicillin/clavulanic acid and azithromycin, in 62.4% to lincomycin. Sensitivity to ciprofloxacin was detected in 85.7% of patients, in 14.3% - moderate resistance.

A study of bacterial pathogens and antibiotic susceptibility patterns in chronic suppurative otitis media.

PubMed

Mofatteh, M R; Shahabian Moghaddam, F; Yousefi, M; Namaei, M H

2018-01-01

To assess the frequency of bacterial agents in chronic suppurative otitis media and the antibiotic susceptibility patterns of isolates among patients. A total of 185 patients clinically diagnosed with chronic suppurative otitis media were interviewed and middle-ear effusion samples were collected using sterile swabs. All bacterial isolates were identified by conventional microbiological methods. Antibiotic susceptibility patterns of the isolates were determined by Kirby-Bauer disc diffusion. Staphylococci spp. (64.9 per cent) were the most prevalent bacteria isolated, followed by Klebsiella spp. (12.9 per cent) and Pseudomonas aeruginosa (10.3 per cent). The most effective antibiotic for treatment of bacterial chronic suppurative otitis media was ciprofloxacin. Statistical analysis showed no significant difference in bacterial infestations among chronic suppurative otitis media patients and the antimicrobial susceptibility patterns of the bacterial isolates based on gender and age (p > 0.05). Our findings highlight the importance of a continuous and periodic evaluation of the bacteriological profile and antibiotic susceptibility patterns in chronic suppurative otitis media patients for efficacious treatment of the infection.

Aptamer-Based Biosensors for Antibiotic Detection: A Review.

PubMed

Mehlhorn, Asol; Rahimi, Parvaneh; Joseph, Yvonne

2018-06-11

Antibiotic resistance and, accordingly, their pollution because of uncontrolled usage has emerged as a serious problem in recent years. Hence, there is an increased demand to develop robust, easy, and sensitive methods for rapid evaluation of antibiotics and their residues. Among different analytical methods, the aptamer-based biosensors (aptasensors) have attracted considerable attention because of good selectivity, specificity, and sensitivity. This review gives an overview about recently-developed aptasensors for antibiotic detection. The use of various aptamer assays to determine different groups of antibiotics, like β-lactams, aminoglycosides, anthracyclines, chloramphenicol, (fluoro)quinolones, lincosamide, tetracyclines, and sulfonamides are presented in this paper.

Bacteriuria amongst Pregnant Women in the Buea Health District, Cameroon: Prevalence, Predictors, Antibiotic Susceptibility Patterns and Diagnosis

PubMed Central

Mokube, Morike Ngoe; Atashili, Julius; Halle-Ekane, Gregory Edie; Ikomey, George M.; Ndumbe, Peter M.

2013-01-01

Background Bacteriuria is associated with significant maternal and foetal risks. However, its prevalence is not known in our community. Objectives This study was carried out to determine the prevalence and predictors of bacteriuria in pregnant women of the Buea Health District (BHD) as well as the antibiotic sensitivity patterns of bacterial isolates. It also sought to determine the diagnostic performance of the nitrite and leucocyte esterase tests in detecting bacteriuria in these women. Methods An observational analytic cross-sectional study was carried out amongst pregnant women attending selected antenatal care centres in Buea. We recruited 102 consenting pregnant women for the study. Demographic and clinical data were collected using structured questionnaires. Clean catch midstream urine was collected from each participant in sterile leak proof containers. Samples were examined biochemically, microscopically and by culture. Significant bacteriuria was defined as the presence of ≥108 bacteria/L of cultured urine. Identification and susceptibility of isolates was performed using API 20E and ATB UR EU (08) (BioMerieux, Marcy l'Etoile, France). Results Significant bacteriuria was found in the urine of 24 of the 102 women tested giving a bacteriuria prevalence of 23.5% in pregnant women of the BHD. Asymptomatic bacteriuria was detected in 8(7.8%) of the women. There was no statistically significant predictor of bacteriuria. Escherichia coli were the most isolated (33%) uropathogens and were 100% sensitive to cefixime, cefoxitin and cephalothin. The nitrite and leucocyte esterase tests for determining bacteriuria had sensitivities of 8%, 20.8% and specificities of 98.7% and 80.8% respectively. Conclusion Bacteriuria is frequent in pregnant women in the BHD suggesting the need for routine screening by urine culture. Empiric treatment with cefixime should be instituted until results of urine culture and sensitivity are available. Nitrite and leucocyte esterase tests were not sensitive enough to replace urine culture as screening tests. PMID:23976983

Bacteriuria amongst pregnant women in the Buea Health District, Cameroon: prevalence, predictors, antibiotic susceptibility patterns and diagnosis.

PubMed

Mokube, Morike Ngoe; Atashili, Julius; Halle-Ekane, Gregory Edie; Ikomey, George M; Ndumbe, Peter M

2013-01-01

Bacteriuria is associated with significant maternal and foetal risks. However, its prevalence is not known in our community. This study was carried out to determine the prevalence and predictors of bacteriuria in pregnant women of the Buea Health District (BHD) as well as the antibiotic sensitivity patterns of bacterial isolates. It also sought to determine the diagnostic performance of the nitrite and leucocyte esterase tests in detecting bacteriuria in these women. An observational analytic cross-sectional study was carried out amongst pregnant women attending selected antenatal care centres in Buea. We recruited 102 consenting pregnant women for the study. Demographic and clinical data were collected using structured questionnaires. Clean catch midstream urine was collected from each participant in sterile leak proof containers. Samples were examined biochemically, microscopically and by culture. Significant bacteriuria was defined as the presence of ≥10⁸ bacteria/L of cultured urine. Identification and susceptibility of isolates was performed using API 20E and ATB UR EU (08) (BioMerieux, Marcy l'Etoile, France). Significant bacteriuria was found in the urine of 24 of the 102 women tested giving a bacteriuria prevalence of 23.5% in pregnant women of the BHD. Asymptomatic bacteriuria was detected in 8(7.8%) of the women. There was no statistically significant predictor of bacteriuria. Escherichia coli were the most isolated (33%) uropathogens and were 100% sensitive to cefixime, cefoxitin and cephalothin. The nitrite and leucocyte esterase tests for determining bacteriuria had sensitivities of 8%, 20.8% and specificities of 98.7% and 80.8% respectively. Bacteriuria is frequent in pregnant women in the BHD suggesting the need for routine screening by urine culture. Empiric treatment with cefixime should be instituted until results of urine culture and sensitivity are available. Nitrite and leucocyte esterase tests were not sensitive enough to replace urine culture as screening tests.

Combined Effects and Cross-Interactions of Different Antibiotics and Polypeptides in Salmonella bredeney.

PubMed

Ju, Xiangyu; Zhu, Mengjiao; Han, Jinzhi; Lu, Zhaoxin; Zhao, Haizhen; Bie, Xiaomei

2018-05-24

Salmonella spp. are health-threatening foodborne pathogens. The increasingly common spread of antibiotic-resistant Salmonella spp. is a major public healthcare issue worldwide. In this study, we wished to explore (1) antibiotic or polypeptide combinations to inhibit multidrug-resistant Salmonella bredeney and (2) the regulation of cross-resistance and collateral sensitivity of antibiotics and polypeptides. We undertook a study to select antibiotic combinations. Then, we promoted drug-resistant strains of S. bredeney after 15 types of antibiotic treatment. From each evolving population, the S. bredeney strain was exposed to a particular single drug. Then, we analyzed how the evolved S. bredeney strains acquired resistance or susceptibility to other drugs. A total of 105 combinations were tested against S. bredeney following the protocols of CLSI-2016 and EUCAST-2017. The synergistic interactions between drug pairings were diverse. Notably, polypeptides were more likely to be linked to synergistic combinations: 56% (19/34) of the synergistic pairings were relevant to polypeptides. Simultaneously, macrolides demonstrated antagonism toward polypeptides. The latter were more frequently related to collateral sensitivity than the other drugs because the other 13 drugs sensitized S. bredeney to polypeptides. In an experimental evolution involving 15 drugs, single drug-evolved strains were examined against the other 14 drugs, and the results were compared with the minimal inhibitory concentration of the ancestral strain. Single drug-evolved S. bredeney strains could alter the sensitivity to other drugs, and S. bredeney evolution against antibiotics could sensitize it to polypeptides.

Background antibiotic resistance patterns in antibiotic-free pastured poultry production

USDA-ARS?s Scientific Manuscript database

Antibiotic resistance (AR) is a significant public health issue, and agroecosystems are often viewed as major environmental sources of antibiotic resistant foodborne pathogens. While the use of antibiotics in agroecosystems can potentially increase AR, appropriate background resistance levels in th...

Comparison of antibiotic resistance patterns in collections of Escherichia coli and Proteus mirabilis uropathogenic strains.

PubMed

Adamus-Bialek, Wioletta; Zajac, Elzbieta; Parniewski, Pawel; Kaca, Wieslaw

2013-04-01

Escherichia coli and Proteus mirabilis are important urinary tract pathogens. The constant increase in the antibiotic resistance of clinical bacterial strains has become an important clinical problem. The aim of this study was to compare the antibiotic resistance of 141 clinical (Sweden and Poland) and 42 laboratory (Czech Republic) P. mirabilis strains and 129 clinical (Poland) uropathogenic E. coli strains. The proportion of unique versus diverse patterns in Swedish clinical and laboratory P. mirabilis strain collections was comparable. Notably, a similar proportion of unique versus diverse patterns was observed in Polish clinical P. mirabilis and E. coli strain collections. Mathematical models of the antibiotic resistance of E. coli and P. mirabilis strains based on Kohonen networks and association analysis are presented. In contrast to the three clinical strain collections, which revealed complex associations with the antibiotics tested, laboratory P. mirabilis strains provided simple antibiotic association diagrams. The monitoring of antibiotic resistance patterns of clinical E. coli and P. mirabilis strains plays an important role in the treatment procedures for urinary tract infections and is important in the context of the spreading drug resistance in uropathogenic strain populations. The adaptability and flexibility of the genomes of E. coli and P. mirabilis strains are discussed.

A study of pre-antibiotic bacteriology in 125 patients with necrotizing enterocolitis.

PubMed

Chan, K L; Saing, H; Yung, R W; Yeung, Y P; Tsoi, N S

1994-01-01

Over a five-year period, 125 newborns with necrotizing enterocolitis (NEC) were managed by us. Their mean birthweight was 1700 g and mean maturity was 32 weeks. Before commencement of antibiotics, routine septic work-up was done in order to define the bacterial spectrum and antibiotic sensitivity. The study includes aerobic and anaerobic cultures of gastric and pharyngeal aspirates, blood cultures, umbilical swabs and culture of umbilical catheter tips in relevant cases. Peritoneal swab results were also analyzed if laparatomy was performed. Positive cultures were present in 45 patients (36%) with 55 positive specimens. Fifteen types of organism were isolated: the commonest was Enterobacter (29%), followed by E. coli (14.5%) and Klebsiella (13%). They were resistant to ampicillin and first-generation cephalosporin. These organisms were usually opportunistic pathogens. Overgrowth of them may be the cause of NEC. Regular review of the antibiotic sensitivity of these organisms allows prompt and appropriate choice of antibiotics. At the same time, antibiotic sensitivity for these organisms was analyzed to guide us in the choice of antibiotic therapy.

Cooperation, competition and antibiotic resistance in bacterial colonies.

PubMed

Frost, Isabel; Smith, William P J; Mitri, Sara; Millan, Alvaro San; Davit, Yohan; Osborne, James M; Pitt-Francis, Joe M; MacLean, R Craig; Foster, Kevin R

2018-06-01

Bacteria commonly live in dense and genetically diverse communities associated with surfaces. In these communities, competition for resources and space is intense, and yet we understand little of how this affects the spread of antibiotic-resistant strains. Here, we study interactions between antibiotic-resistant and susceptible strains using in vitro competition experiments in the opportunistic pathogen Pseudomonas aeruginosa and in silico simulations. Selection for intracellular resistance to streptomycin is very strong in colonies, such that resistance is favoured at very low antibiotic doses. In contrast, selection for extracellular resistance to carbenicillin is weak in colonies, and high doses of antibiotic are required to select for resistance. Manipulating the density and spatial structure of colonies reveals that this difference is partly explained by the fact that the local degradation of carbenicillin by β-lactamase-secreting cells protects neighbouring sensitive cells from carbenicillin. In addition, we discover a second unexpected effect: the inducible elongation of cells in response to carbenicillin allows sensitive cells to better compete for the rapidly growing colony edge. These combined effects mean that antibiotic treatment can select against antibiotic-resistant strains, raising the possibility of treatment regimes that suppress sensitive strains while limiting the rise of antibiotic resistance. We argue that the detailed study of bacterial interactions will be fundamental to understanding and overcoming antibiotic resistance.

Influence of Hydrogen Peroxide, Lactic Acid, and Surfactants from Vaginal Lactobacilli on the Antibiotic Sensitivity of Opportunistic Bacteria.

PubMed

Sgibnev, Andrey; Kremleva, Elena

2017-06-01

We studied as hydrogen peroxide, lactic acid, or surfactants from clinical isolates of vaginal lactobacilli and cell-free supernatants from probiotic strain LCR35 can influence on the sensitivity of opportunistic bacteria to antibiotics. We found that the most effective in increasing sensitivity to antibiotics were hydrogen peroxide and surfactants or their combination but no lactic acid. In some cases, the effect of the composition of hydrogen peroxide and surfactants was clearly higher than the sum of effects of these substances alone. With using of the supernatant of LCR35 was shown that the combination of surfactant and lactate has greater effect compared with surfactants alone. In concluding, metabolites of vaginal lactobacilli are suitable for the role of "antibiotic assistants" and it can help solve the problems the antibiotic resistance.

National ambulatory antibiotic prescribing patterns for pediatric urinary tract infection, 1998-2007.

PubMed

Copp, Hillary L; Shapiro, Daniel J; Hersh, Adam L

2011-06-01

The goal of this study was to investigate patterns of ambulatory antibiotic use and to identify factors associated with broad-spectrum antibiotic prescribing for pediatric urinary tract infections (UTIs). We examined antibiotics prescribed for UTIs for children aged younger than 18 years from 1998 to 2007 using the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey. Amoxicillin-clavulanate, quinolones, macrolides, and second- and third-generation cephalosporins were classified as broad-spectrum antibiotics. We evaluated trends in broad-spectrum antibiotic prescribing patterns and performed multivariable logistic regression to identify factors associated with broad-spectrum antibiotic use. Antibiotics were prescribed for 70% of pediatric UTI visits. Trimethoprim-sulfamethoxazole was the most commonly prescribed antibiotic (49% of visits). Broad-spectrum antibiotics were prescribed one third of the time. There was no increase in overall use of broad-spectrum antibiotics (P = .67); however, third-generation cephalosporin use doubled from 12% to 25% (P = .02). Children younger than 2 years old (odds ratio: 6.4 [95% confidence interval: 2.2-18.7, compared with children 13-17 years old]), females (odds ratio: 3.6 [95% confidence interval: 1.6-8.5]), and temperature ≥ 100.4°F (odds ratio: 2.9 [95% confidence interval: 1.0-8.6]) were independent predictors of broad-spectrum antibiotic prescribing. Race, physician specialty, region, and insurance status were not associated with antibiotic selection. Ambulatory care physicians commonly prescribe broad-spectrum antibiotics for the treatment of pediatric UTIs, especially for febrile infants in whom complicated infections are more likely. The doubling in use of third-generation cephalosporins suggests that opportunities exist to promote more judicious antibiotic prescribing because most pediatric UTIs are susceptible to narrower alternatives.

National Ambulatory Antibiotic Prescribing Patterns for Pediatric Urinary Tract Infection, 1998–2007

PubMed Central

Shapiro, Daniel J.; Hersh, Adam L.

2011-01-01

OBJECTIVE: The goal of this study was to investigate patterns of ambulatory antibiotic use and to identify factors associated with broad-spectrum antibiotic prescribing for pediatric urinary tract infections (UTIs). METHODS: We examined antibiotics prescribed for UTIs for children aged younger than 18 years from 1998 to 2007 using the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey. Amoxicillin-clavulanate, quinolones, macrolides, and second- and third-generation cephalosporins were classified as broad-spectrum antibiotics. We evaluated trends in broad-spectrum antibiotic prescribing patterns and performed multivariable logistic regression to identify factors associated with broad-spectrum antibiotic use. RESULTS: Antibiotics were prescribed for 70% of pediatric UTI visits. Trimethoprim-sulfamethoxazole was the most commonly prescribed antibiotic (49% of visits). Broad-spectrum antibiotics were prescribed one third of the time. There was no increase in overall use of broad-spectrum antibiotics (P = .67); however, third-generation cephalosporin use doubled from 12% to 25% (P = .02). Children younger than 2 years old (odds ratio: 6.4 [95% confidence interval: 2.2–18.7, compared with children 13–17 years old]), females (odds ratio: 3.6 [95% confidence interval: 1.6–8.5]), and temperature ≥100.4°F (odds ratio: 2.9 [95% confidence interval: 1.0–8.6]) were independent predictors of broad-spectrum antibiotic prescribing. Race, physician specialty, region, and insurance status were not associated with antibiotic selection. CONCLUSIONS: Ambulatory care physicians commonly prescribe broad-spectrum antibiotics for the treatment of pediatric UTIs, especially for febrile infants in whom complicated infections are more likely. The doubling in use of third-generation cephalosporins suggests that opportunities exist to promote more judicious antibiotic prescribing because most pediatric UTIs are susceptible to narrower alternatives. PMID:21555502

Patterns of antibiotic use in the community and challenges of antibiotic surveillance in a lower-middle-income country setting: a repeated cross-sectional study in Vellore, South India.

PubMed

Chandy, Sujith J; Thomas, Kurien; Mathai, Elizabeth; Antonisamy, Belavendra; Holloway, Kathleen A; Stalsby Lundborg, Cecilia

2013-01-01

There is considerable evidence linking antibiotic usage to bacterial resistance. Intervention strategies are needed to contain antibiotic use and thereby resistance. To plan appropriate strategies, it is imperative to undertake surveillance in the community to monitor antibiotic encounters and drivers of specific antibiotic misuse. Such surveillance is rarely in place in lower-middle-income countries (LMICs). This study describes antibiotic patterns and challenges faced while developing such surveillance systems in an LMIC. Surveillance of antibiotic encounters (prescriptions and dispensations) was carried out using a repeated cross-sectional design for 2 years in Vellore, south India. Every month, patients attending 30 health facilities (small hospitals, general practitioner clinics and pharmacy shops) were observed until 30 antibiotic encounters were attained in each. Antibiotic use was expressed as the percentage of encounters containing specific antibiotics and defined daily doses (DDDs)/100 patients. Bulk antibiotic sales data were also collected. Over 2 years, a total of 52,788 patients were observed and 21,600 antibiotic encounters (40.9%) were accrued. Fluoroquinolones and penicillins were widely used. Rural hospitals used co-trimoxazole more often and urban private hospitals used cephalosporins more often; 41.1% of antibiotic prescriptions were for respiratory infections. The main challenges in surveillance included issues regarding sampling, data collection, denominator calculation and sustainability. Patterns of antibiotic use varied across health facilities, suggesting that interventions should involve all types of health facilities. Although challenges were encountered, our study shows that it is possible to develop surveillance systems in LMICs and the data generated may be used to plan feasible interventions, assess impact and thereby contain resistance.

Culture and Real-Time PCR Based Maternal Screening and Antibiotic Susceptibility for Group B Streptococcus: An Iranian Experience.

PubMed

Goudarzi, Gholamreza; Ghafarzadeh, Masoumeh; Shakib, Pegah; Anbari, Khatereh

2015-04-19

Vertical Transmission of group B streptococcus (GBS) from a vagina colonized mother to her infant upon rupture of membranes (ROM) or after the onset of labor can cause life-threatening infections in newborn. Although intrapartum antibiotic prophylaxis (IAP) can significantly decrease neonatal GBS diseases, this issue has potentiated the emergence of antibiotic resistance strains. Our study examined the colonization rate of GBS using real-time PCR and culture methods, and trends in antibiotic resistance of GBS isolates obtained from pregnant women in Khorramabad, Iran. In this cross-sectional study, two vaginal-rectal swabs were collected and analyzed separately from 100 pregnant women at 35-37 weeks of gestation by convenience sampling method. The specimens were subjected to GBS detection using real-time PCR assay and standard culture. Susceptibility pattern of the GBS isolates was examined using the disk diffusion method. GBS carriage rate was 17% and 19% using culture and real-time PCR, respectively. In six samples, the culture was positive and the real-time PCR was negative. Sensitivity and specificity for real-time PCR were 72.7% and 96.1%, respectively using culture as the gold standard. Amongst twenty-two isolates examined, 100% resistance to erythromycin and clindamycin was observed. One isolate (4%) exhibited resistance to penicillin. Considering the relatively high GBS carriage rate in Khorramabad, routine antepartum screening for GBS is recommended. Penicillin can remain the antibiotic of choice for IAP; however, in penicillin-allergic mothers, vancomycin can be an alternative antibiotic.

Prescribing antibiotics in diabetic foot infection: what is the role of initial microscopy and culture of tissue samples?

PubMed

Chisman, Robin; Lowry, Danielle; Saeed, Mujahid A; Tiwari, Alok; David, Miruna D

2017-08-01

The aim of this study was to evaluate the role of microscopy, Gram stain and the culture of tissue samples in the antibiotic treatment of patients with diabetic foot infection. A retrospective review of patients with a diabetic foot infection was undertaken. Data analysed included the severity of infection, antibiotic prescribing patterns, microscopy and culture results. A total of 71 patients were included, from whom 114 tissue samples were collected. Gram stain results were in agreement with final culture results in 45·8% (n = 54) of samples. Overall sensitivity and specificity of the Gram stains were low (74·5% and 69·8%, respectively), although the specificity for Gram-negative rods was high (98·5%). The presence or absence of 'pus cells' on microscopy was a poor predictor of culture results. Empirical prescribing of antibiotics was in accordance with local policy in 31·1% of patients, improving to 86·8 % following culture results. Microscopy, a skilled laboratory procedure, was generally a poor predictor of tissue culture results. However, the presence of Gram-negative rods was suggestive of isolation in the culture of such organisms and could allow the early broadening of antibiotic treatment. Despite initial poor compliance of empirical antibiotic treatment regimens, prescribing was adjusted in light of culture results, suggesting these were important for clinicians. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Persistence of antibiotic resistance: evaluation of a probiotic approach using antibiotic-sensitive Megasphaera elsdenii strains to prevent colonization of swine by antibiotic-resistant strains.

PubMed

Stanton, Thad B; Humphrey, Samuel B

2011-10-01

Megasphaera elsdenii is a lactate-fermenting, obligately anaerobic bacterium commonly present in the gastrointestinal tracts of mammals, including humans. Swine M. elsdenii strains were previously shown to have high levels of tetracycline resistance (MIC=64 to >256 μg/ml) and to carry mosaic (recombinant) tetracycline resistance genes. Baby pigs inherit intestinal microbiota from the mother sow. In these investigations we addressed two questions. When do M. elsdenii strains from the sow colonize baby pigs? Can five antibiotic-sensitive M. elsdenii strains administered intragastrically to newborn pigs affect natural colonization of the piglets by antibiotic-resistant (AR) M. elsdenii strains from the mother? M. elsdenii natural colonization of newborn pigs was undetectable (<10(4) CFU/g [wet weight] of feces) prior to weaning (20 days after birth). After weaning, all pigs became colonized (4 × 10(5) to 2 × 10(8) CFU/g feces). In a separate study, 61% (76/125) of M. elsdenii isolates from a gravid sow never exposed to antibiotics were resistant to chlortetracycline, ampicillin, or tylosin. The inoculation of the sow's offspring with mixtures of M. elsdenii antibiotic-sensitive strains prevented colonization of the offspring by maternal AR strains until at least 11 days postweaning. At 25 and 53 days postweaning, however, AR strains predominated. Antibiotic susceptibility phenotypes and single nucleotide polymorphism (SNP)-based identities of M. elsdenii isolated from sow and offspring were unexpectedly diverse. These results suggest that dosing newborn piglets with M. elsdenii antibiotic-sensitive strains delays but does not prevent colonization by maternal resistant strains. M. elsdenii subspecies diversity offers an explanation for the persistence of resistant strains in the absence of antibiotic selection.

Aerobic vaginal pathogens and their sensitivity pattern.

PubMed

Mumtaz, Shamim; Ahmad, Mumtaz; Aftab, Irum; Akhtar, Naeem; ul Hassan, Masood; Hamid, Abdul

2008-01-01

The vaginal flora is a complicated environment, containing dozens of microbiological species in variable quantities and relative proportions. The frequent cause of vaginal discharge is an infection or colonization with different microorganisms. Some pathologic conditions causing vaginitis are well defined yet, 7-72% of women with vaginitis may remain undiagnosed and such forms of abnormal vaginal flora neither considered as normal, nor can be called bacterial vaginosis have been termed as 'intermediate flora' and its management probably differ from that of bacterial vaginosis. It is of crucial importance in pregnant females at risk of preterm delivery. The present study has been conducted especially to elucidate this type of aerobic vaginal isolates and their culture and sensitivity towards currently used antibiotics. This study was conducted at the Microbiology Department of Fauji Foundation Hospital, Rawalpindi over a period of two years (April 2004-March 2006). One thousand, nine hundred and twenty three high vaginal swabs, both from indoor and outdoor patients were collected, cultured and their susceptibility to various antibiotics was determined. Significant growth was obtained in 731 samples. The highest frequency of infection (39.5%) was observed at 31-40 years followed by 41-50 years (35.8%). About 76% were from outdoor and 24% were from indoor patients. Staphylococcus aureus was the most prevalent vaginal pathogen at 11-60 yrs & with highest prevalence at 31-40 years followed by 41-50 years. It was a predominant pathogen in both indoor (35%) as well as outdoor (41.6%) patients, followed by enteric gram-negative bacilli and other gram-positive cocci. There were very few antibiotics among the conventionally available aminoglycosides, third generation cephalosporins, penicillin, quinolones, sulfonamides and tetracyclines possessing good sensitivity (> 80%) against any one the common aerobic vaginal pathogens. The effective chemotherapeutics agents belong to the groups of carbapenems and beta-lactams beta-lactamase inhibitor combinations. The high prevalence of gynaecological infections demands that the patients with gynaecological symptoms be investigated thoroughly. Culture must invariably be done. Currently the antibiotics showing good sensitivity are very expensive. So there is a need for an effective antimicrobial policy. Effective drug should be reserved for the treatment of serious life threatening situations only.

Urinary tract infection diagnosis and response to antibiotics using Raman spectroscopy

NASA Astrophysics Data System (ADS)

Kastanos, Evdokia; Kyriakides, Alexandros; Hadjigeorgiou, Katerina; Pitris, Constantinos

2009-02-01

Urinary tract infection diagnosis and antibiogram require a 48 hour waiting period using conventional methods. This results in ineffective treatments, increased costs and most importantly in increased resistance to antibiotics. In this work, a novel method for classifying bacteria and determining their sensitivity to an antibiotic using Raman spectroscopy is described. Raman spectra of three species of gram negative Enterobacteria, most commonly responsible for urinary tract infections, were collected. The study included 25 samples each of E.coli, Klebsiella p. and Proteus spp. A novel algorithm based on spectral ratios followed by discriminant analysis resulted in classification with over 94% accuracy. Sensitivity and specificity for the three types of bacteria ranged from 88-100%. For the development of an antibiogram, bacterial samples were treated with the antibiotic ciprofloxacin to which they were all sensitive. Sensitivity to the antibiotic was evident after analysis of the Raman signatures of bacteria treated or not treated with this antibiotic as early as two hours after exposure. This technique can lead to the development of new technology for urinary tract infection diagnosis and antibiogram with same day results, bypassing urine cultures and avoiding all undesirable consequences of current practice.

Klebsiella pneumonia, a Microorganism that Approves the Non-linear Responses to Antibiotics and Window Theory after Exposure to Wi-Fi 2.4 GHz Electromagnetic Radiofrequency Radiation

PubMed Central

Taheri, M.; Mortazavi, S. M. J.; Moradi, M.; Mansouri, Sh.; Nouri, F.; Mortazavi, S. A. R.; Bahmanzadegan, F.

2015-01-01

Background Drug resistance is widely believed to be an increasingly serious threat to global public health. We have previously reported that short term exposure of microorganisms to diagnostic ultrasound waves could significantly alter their sensitivity to antibiotics. In our previous studies, Klebsiella pneumoniae showed major differences in the sensitivity to antibiotics in exposed and non-exposed samples. This study was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation. Materials and Methods In this in vitro study, three replicate agar plates were used for each test. The antibiotic susceptibility test was carried out using disc diffusion method on Mueller Hinton agar plates and the inhibition zones in both control and exposed groups were measured. A common Wi-Fi router was used in this study as the radiofrequency exposure source. Irradiated samples were exposed to Wi-Fi radiofrequency radiation for 3, 4.5 and 8 hours. Results Statistically significant variations of sensitivity to antibiotics were found for all studied antibiotics after 4.5 hours of RF exposure, compared to non-exposed bacteria. Interestingly, the mean diameters of the inhibition zones after 3 hours of exposure were less than those exposed for 4.5 hours. Following this rise in the sensitivity to antibiotics, a fall was observed in the bacteria exposed for 8 hours for all studied antibiotics. Conclusion The findings of this study show a statistically significant rise in the sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation. As in this study a minimum level of effect was needed for the induction of adaptive response, these results also confirm the validity of the so-called “window theory”. PMID:26396967

Klebsiella pneumonia, a Microorganism that Approves the Non-linear Responses to Antibiotics and Window Theory after Exposure to Wi-Fi 2.4 GHz Electromagnetic Radiofrequency Radiation.

PubMed

Taheri, M; Mortazavi, S M J; Moradi, M; Mansouri, Sh; Nouri, F; Mortazavi, S A R; Bahmanzadegan, F

2015-09-01

Drug resistance is widely believed to be an increasingly serious threat to global public health. We have previously reported that short term exposure of microorganisms to diagnostic ultrasound waves could significantly alter their sensitivity to antibiotics. In our previous studies, Klebsiella pneumoniae showed major differences in the sensitivity to antibiotics in exposed and non-exposed samples. This study was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation. In this in vitro study, three replicate agar plates were used for each test. The antibiotic susceptibility test was carried out using disc diffusion method on Mueller Hinton agar plates and the inhibition zones in both control and exposed groups were measured. A common Wi-Fi router was used in this study as the radiofrequency exposure source. Irradiated samples were exposed to Wi-Fi radiofrequency radiation for 3, 4.5 and 8 hours. Statistically significant variations of sensitivity to antibiotics were found for all studied antibiotics after 4.5 hours of RF exposure, compared to non-exposed bacteria. Interestingly, the mean diameters of the inhibition zones after 3 hours of exposure were less than those exposed for 4.5 hours. Following this rise in the sensitivity to antibiotics, a fall was observed in the bacteria exposed for 8 hours for all studied antibiotics. The findings of this study show a statistically significant rise in the sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation. As in this study a minimum level of effect was needed for the induction of adaptive response, these results also confirm the validity of the so-called "window theory".

Bacterial Cheating Limits the Evolution of Antibiotic Resistance

NASA Astrophysics Data System (ADS)

Yurtsev, Eugene; Xiao Chao, Hui; Datta, Manoshi; Artemova, Tatiana; Gore, Jeff

2012-02-01

The emergence of antibiotic resistance in bacteria is a significant health concern. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removal of the antibiotic. The presence of a cooperative mechanism of resistance suggests that a cheater strain - which does not contribute to breaking down the antibiotic - may be able to take advantage of resistant cells. We find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We use a simple model in conjunction with difference equations to explain the observed population dynamics as a function of cell density and antibiotic concentration. Our experimental difference equations resemble the logistic map, raising the possibility of oscillations or even chaotic dynamics.

Vancomycin-Resistance Enterococci Infections in the Department of the Defense: Annual Report 2014

DTIC Science & Technology

2015-07-22

change in 2014 as VRE continues to predominately affect elderly females and manifest as urinary tract infections ( UTIs ). In addition, antibiotic...urinary tract infections ( UTIs ). In addition, antibiotic susceptibility patterns did not substantially change in 2014. Daptomycin, linezolid and...the infection continues to predominately affect elderly females and manifest as UTIs . In addition, antibiotic susceptibility patterns did not

The Biogeography of Putative Microbial Antibiotic Production

PubMed Central

Bryant, Jessica A.; Charkoudian, Louise K.; Docherty, Kathryn M.; Jones, Evan; Kembel, Steven W.; Green, Jessica L.; Bohannan, Brendan J. M.

2015-01-01

Understanding patterns in the distribution and abundance of functional traits across a landscape is of fundamental importance to ecology. Mapping these distributions is particularly challenging for species-rich groups with sparse trait measurement coverage, such as flowering plants, insects, and microorganisms. Here, we use likelihood-based character reconstruction to infer and analyze the spatial distribution of unmeasured traits. We apply this framework to a microbial dataset comprised of 11,732 ketosynthase alpha gene sequences extracted from 144 soil samples from three continents to document the spatial distribution of putative microbial polyketide antibiotic production. Antibiotic production is a key competitive strategy for soil microbial survival and performance. Additionally, novel antibiotic discovery is highly relevant to human health, making natural antibiotic production by soil microorganisms a major target for bioprospecting. Our comparison of trait-based biogeographical patterns to patterns based on taxonomy and phylogeny is relevant to our basic understanding of microbial biogeography as well as the pressing need for new antibiotics. PMID:26102275

Nasal carriage and antimicrobial susceptibility of Staphylococcus aureus in healthy preschool children in Ujjain, India.

PubMed

Pathak, Ashish; Marothi, Yogyata; Iyer, Rama V; Singh, Binita; Sharma, Megha; Eriksson, Bo; Macaden, Ragini; Lundborg, Cecilia Stålsby

2010-12-29

There is increasing evidence that community acquired S. aureus infections are spreading among healthy children. Nasal colonization with S. aureus plays pivotal role in the increasing prevalence of resistant community acquired S. aureus infections worldwide. A regular surveillance system is important in ensuring quality of patient care. The aim of the study was to assess the prevalence of and the factors associated with nasal carriage of S. aureus and its antibiotic sensitivity pattern among healthy children in Ujjain, India. A prospective study was done in paediatric outpatient clinics of R.D. Gardi medical college Ujjain, India. Healthy children from 1 month to 59 months of age were included. Information on previously known risk factors for nasal colonization was collected using a pre-tested questionnaire. Swabs from anterior nares were collected and transported in Amies transport media with charcoal and cultured on 5% sheep blood agar. Antibiotic sensitivity tests were performed using Kirby Bauer's disc diffusion method according to performance standards of Clinical and Laboratory Standard Institute guidelines. Of the 1,562 children from 1-month up-to five years of age included in the study 98 children tested positive for nasal carriage of S. aureus. The prevalence of nasal carriage of S. aureus was 6.3% (95% CI 5.1-7.5) out of which 16.3% (95% CI 8.9-23.8) were methicillin-resistant S. aureus (MRSA). The factors associated with nasal carriage were "child attending preschool" (OR 4.26, 95% CI 2.25-8.03; P = 0.007) or "school" (OR 3.02, 95% CI 1.27-7.18; P < 0.001) and "family size more than 10 members" (OR 2.76 95% CI 1.06-7.15; P = 0.03). The sensitivity pattern of isolated S. aureus showed resistance to commonly used oral antibiotics while resistance to glycopeptides was not noted. We found a relatively low rate of nasal carriage of S. aureus in children below five years when compared to children of older age groups in India. Yet, prevalence of MRSA was relatively high.

Antibiotic prophylaxis patterns of Finnish dentists performing dental implant surgery.

PubMed

Pyysalo, Mikko; Helminen, Mika; Antalainen, Anna-Kaisa; Sándor, George K; Wolff, Jan

2014-11-01

The peri-operative use of prophylactic antibiotics in clinically healthy patients undergoing dental implant surgery is very common in Finland. While antibiotics are prescribed with the hope of preventing both local and systemic complications, their application and utilization is not uniform. The aim of this study was to assess the variation in prescribing patterns among Finnish dentists performing dental implant placement operations. This study also aimed to examine the possible relationship between early implant removal and the use of the prophylactic antibiotics in Finland. The National Institute for Health and Welfare in Finland granted permission to access the Finnish Dental Implant Register. The peri-operative antibiotic prophylaxis prescribing patterns were assessed in a total of 110 543 dental implant placement procedures and 1038 dental implant removal operations performed in Finland between April 1994 and April 2012. A total of 61 different antibiotics or combinations were prescribed peri-operatively during implant placements in Finland between 1994-2012. Phenoxymethylpenicillin was the most commonly prescribed drug (72.2%). No statistically significant difference in early implant removal rates could be found between patients who had or had not received peri-operative prophylaxis. However, patients who had received peri-operative prophylaxis had statistically significant longer implant survival rates. There is a variation in antibiotic prescribing patterns among Finnish dentists placing dental implants. The results suggest that the use of prophylactic antibiotics has little effect on the prevention of primary implant surgery-related complications and, hence, success rates.

Bacterial cheating limits the evolution of antibiotic resistance

NASA Astrophysics Data System (ADS)

Chao, Hui Xiao; Datta, Manoshi; Yurtsev, Eugene; Gore, Jeff

2011-03-01

The widespread use of antibiotics has led to the evolution of resistance in bacteria. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removing the antibiotic. The cooperative nature of this growth suggests that a cheater strain--which does not contribute to breaking down the antibiotic--may be able to take advantage of cells cooperatively inactivating the antibiotic. Here we experimentally find that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We observe stable coexistence between the two strains and find that a simple model successfully explains the behavior as a function of antibiotic concentration and cell density. We anticipate that our results will provide insight into the evolutionary origin of phenotypic diversity and cooperative behaviors found in nature.

Isolation, identification and sensitivity pattern of microorganisms isolated from the urine of pregnant women.

PubMed

Karim, S; Khan, K I

1994-01-01

The present studies were conducted to detect and identify the microorganism from the urine of pregnant women having urinary tract infection. The antibiotic susceptibility of these isolated microorganisms was also determined. The microorganisms found responsible for the infection were bacteria, fungi, yeast and protozoa. Among the bacteria two were identified as Gram-positive cocci i.e. Staphylococcus aureus and S. epidermidis, the remaining two were Gram-negative bacilli which were Escherichia coil and Pseudomonas aeruginosa. The fungus was identified as AspelEillus niger and the yeast like fungus Candida albican. The only protozoan found in some of the urine samples was Trichomonas vaginalis. These isolated and identified microorganisms were more susceptible to Norfloxacin, Velosef, Minocin, Nitrofurantoin, Malidixic acid and Metronidazole whereas antibiotics Penbritin and Cefaloridine were least effective against these microorganisms.

Antibiotic sensitivity and resistance in Ornithobacterium rhinotracheale strains from Belgian broiler chickens.

PubMed

Devriese, L A; De Herdt, P; Haesebrouck, F

2001-06-01

Establishing the antibiotic sensitivity of the avian respiratory pathogen Ornithobacterium rhinotracheale is difficult because of the organism's complex growth requirements and the unusually frequent occurrence of resistance. The minimal inhibitory concentrations of 10 antibiotics were determined for 45 strains of O. rhinotracheale from Belgian broiler chickens collected from 45 farms between 1995 and 1998. They were compared with the type strain, which was isolated from a turkey, and a strain isolated from a rook. All the broiler strains were resistant to lincomycin and to the beta-lactams ampicillin and ceftiofur. Less than 10% of the strains were sensitive to the macrolides tylosin and spiramycin, tilmicosin and flumequine. A few strains were sensitive to enrofloxacin and doxycycline. All strains were sensitive to tiamulin.

Antibiotic susceptibility profiles for mastitis treatment.

PubMed

Hinckley, L S; Benson, R H; Post, J E; DeCloux, J C

1985-10-01

Susceptibility tests were performed on milk samples representing prevalent mastitis infections in certain herds. Susceptibility patterns of the same bacterial species from several mastitis infections in the same herd were consistent. The herd antibiotic susceptibility profiles were used as a basis for selecting antibiotics for treatment of all such mastitis cases in that herd. A high degree of correlation was seen between the susceptibility test results and treatment results. Susceptibility patterns of the same bacterial species from mastitis infections in different herds varied greatly, which indicated that any one antibiotic would not work equally well against the same bacterial infection in every herd. Therefore, treatment should be selected on the basis of susceptibility test results. When both Streptococcus and Staphylococcus mastitis occurred in the same herd, the susceptibility patterns for the 2 bacterial species varied widely. Therefore, for herds that experienced both streptococcal and staphylococcal mastitis, antibiotics to which both bacterial species were susceptible were used for treatment.

Diversity and antibiotic resistance patterns of Sphingomonadaceae isolates from drinking water.

PubMed

Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

2011-08-15

Sphingomonadaceae (n = 86) were isolated from a drinking water treatment plant (n = 6), tap water (n = 55), cup fillers for dental chairs (n = 21), and a water demineralization filter (n = 4). The bacterial isolates were identified based on analysis of the 16S rRNA gene sequence, and intraspecies variation was assessed on the basis of atpD gene sequence analysis. The isolates were identified as members of the genera Sphingomonas (n = 27), Sphingobium (n = 28), Novosphingobium (n = 12), Sphingopyxis (n = 7), and Blastomonas (n = 12). The patterns of susceptibility to five classes of antibiotics were analyzed and compared for the different sites of isolation and taxonomic groups. Colistin resistance was observed to be intrinsic (92%). The highest antibiotic resistance prevalence values were observed in members of the genera Sphingomonas and Sphingobium and for beta-lactams, ciprofloxacin, and cotrimoxazole. In tap water and in water from dental chairs, antibiotic resistance was more prevalent than in the other samples, mainly due to the predominance of isolates of the genera Sphingomonas and Sphingobium. These two genera presented distinct patterns of association with antibiotic resistance, suggesting different paths of resistance development. Antibiotic resistance patterns were often related to the species rather than to the site or strain, suggesting the importance of vertical resistance transmission in these bacteria. This is the first study demonstrating that members of the family Sphingomonadaceae are potential reservoirs of antibiotic resistance in drinking water.

A competitive trade-off limits the selective advantage of increased antibiotic production.

PubMed

Gerardin, Ylaine; Springer, Michael; Kishony, Roy

2016-09-26

In structured environments, antibiotic-producing microorganisms can gain a selective advantage by inhibiting nearby competing species 1 . However, despite their genetic potential 2,3 , natural isolates often make only small amounts of antibiotics, and laboratory evolution can lead to loss rather than enhancement of antibiotic production 4 . Here, we show that, due to competition with antibiotic-resistant cheater cells, increased levels of antibiotic production can actually decrease the selective advantage to producers. Competing fluorescently labelled Escherichia coli colicin producers with non-producing resistant and sensitive strains on solid media, we found that although producer colonies can greatly benefit from the inhibition of nearby sensitive colonies, this benefit is shared with resistant colonies growing in their vicinity. A simple model, which accounts for such local competitive and inhibitory interactions, suggests that the advantage of producers varies non-monotonically with the amount of production. Indeed, experimentally varying the amount of production shows a peak in selection for producers, reflecting a trade-off between benefit gained by inhibiting sensitive competitors and loss due to an increased contribution to resistant cheater colonies. These results help explain the low level of antibiotic production observed for natural species and can help direct laboratory evolution experiments selecting for increased or novel production of antibiotics.

Detection of tetQ and ermF antibiotic resistance genes in Prevotella and Porphyromonas isolates from clinical specimens and resident microbiota of humans.

PubMed

Arzese, A R; Tomasetig, L; Botta, G A

2000-05-01

Gram-negative anaerobes belonging to the genera Fusobacterium, Prevotella and Porphyromonas were investigated for the presence of tetQ and ermF, which have been shown to be spread by conjugal elements. One hundred isolates from either sites of infection or various body sites in healthy subjects were studied. PCR was used to detect tetQ, and DNA-DNA hybridization studies on EcoRI chromosomal digests were undertaken to detect the presence of tetQ and ermF. Antibiotic sensitivity assays were performed on selected isolates to detect tetracycline, erythromycin and penicillin resistance. Twenty Fusobacterium isolates lacked tetQ, and were tetracycline sensitive. Twenty per cent of Prevotella spp. isolates both from clinical specimens and from healthy subjects were found to possess tetQ. Of 20 Porphyromonas isolates tested, one (Porphyromonas levii) from a case of bacterial vaginosis was shown to possess tetQ in the chromosome. The presence of tetQ was always associated with tetracycline resistance. Four isolates of Prevotella melaninogenica and one isolate of Prevotella were ermF-positive, although expression of erythromycin resistance was not consistently associated with detection of this gene. Antibiotic resistance phenotypes of Prevotella isolates were shown to be related to specific chromosomal restriction patterns by hybridization studies: tetracycline resistance and tetracycline/erythromycin resistance are conferred by Bacteroides tetracycline-resistant ERL elements, whereas the tetracycline/penicillin resistance phenotype could be due to spread of elements identified in Prevotella only. Tetracycline/erythromycin-resistant and tetracycline/erythromycin/penicillin-resistant P. melaninogenica isolates were found in this study. It appeared that the presence of tetQ and ermF in Bacteroides and Prevotella contributed to the persistence of antibiotic resistance isolates within the host and to potential spread to other organisms through conjugal elements.

Epidemiological Features and Antibiotic Resistance Patterns of Haemophilus influenzae Originating from Respiratory Tract and Vaginal Specimens in Pediatric Patients.

PubMed

Li, Jian-Ping; Hua, Chun-Zhen; Sun, Li-Ying; Wang, Hong-Jiao; Chen, Zhi-Min; Shang, Shi-Qiang

2017-12-01

Haemophilus influenzae (H. influenzae) is a common pathogen of respiratory tract infections in children, however, as a possible cause of vulvovaginitis in prepubertal girls, its epidemiological features, antibiotic-resistance patterns, and treatment are seldom noted. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: Specimens obtained from patients were inoculated on Haemophilus selective medium; and drug-sensitivities tests were determined using the disk diffusion method. A cefinase disk was used to detect β-lactamase. A total of 610 H. influenzae strains, 81.6% (498/610) from the respiratory tract and 18.0% (110/610) from the vagina, were identified in the Children's Hospital in 2015. The age of the children with respiratory tract strains were significantly younger than those with vaginal strains (P < .001). The H. influenzae isolation rate in May was the highest. The β-lactamase positive rate was 51.5% (314/610), and 52.5% (320/610) were resistant to ampicillin. The susceptibilities rates to cefuroxime, ampicillin/sulbactam, cefotaxime, clarithromycin, and sulfamethoxazole-trimethoprim were 72.1% (440/610), 95.9%, 96.4% (588/610), 81.8% (499/610), and 36.4% (222/610), respectively. Higher resistance to ampicillin, cefuroxime, clarithromycin, and sulfamethoxazole-trimethoprim were found in respiratory tract strains, compared with vaginal strains (P < .05). All of the patients with H. influenzae in the respiratory tract were cured with oral or intravenous β-lactam antibiotics. Of all patients with vaginal strains, 50% (55/110) were cured with topical ofloxacin gel, and 44.5% (49/110) were cured with oral β-lactam antibiotics. The drug-resistance rates of H. influenzae isolated from vagina were lower than those from the respiratory tract. Topical ofloxacin gel or oral β-lactam antibiotics are effective treatments to eliminate the H. influenza causing infection in the vagina. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Profile of children with urinary tract infection and the utility of urine dipstick as a diagnostic tool.

PubMed

Ojha, A R; Aryal, U R

2014-01-01

Urinary tract infection is a common problem in children and its early diagnosis and treatment is important to prevent long-term complications. Urine dipstick can be an important tool in this respect. The aim of this study is to look at the utility of urine dipstick as a diagnostic tool for UTI and will also see the clinical profile of children with UTI and sensitivity pattern of antibiotics among the isolates of urine culture. Urine samples of all children below 14 years of age who were suspected of urinary tract infection were sent for routine microscopic examination and dipstick testing. Urine culture and sensitivity were sent for those samples that were tested positive for nitrite, leucocyte esterase activity or both. For every fifth sample, which is dipstick negative, a culture and sensitivity testing was done. Among 110 children enrolled, 32(29%) cases had significant bacteriuria. Out of 32 culture positive cases 18(56%) were female. Fever was the main complaint (62.5%)). Escherichia Coli was isolated in 81.25% of cases. Amikacin was sensitive in 93% and amoxicillinwas resistant in 82%. The sensitivity, specificity, positive predictive value, negative predictive value of nitrite test was 65%, 80%, 58%, 85% respectively; those of leucocyte esterase are 84%, 55%, 43%, 89% respectively; those for significant microscopic pyuria >10/hpf were 65%, 74%, 51%, 84% respectively. E. Coli is the commonest uropathogen in children with UTI. Amikacin is the most sensitive antibiotic against all the isolates. A positive dipstick both for nitrite and leucocyte esterase is associated with high sensitivity and specificity for urinary tract infection as compared to either of them positive alone. In addition, urine WBC ≥10/hpf is associated with high probability of UTI.

Normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity, in patients undergoing cataract surgery at Phramongkutklao Hospital.

PubMed

Ratnumnoi, Ravee; Keorochana, Narumon; Sontisombat, Chavalit

2017-01-01

This study aimed to evaluate the normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity. This was a prospective cross-sectional study. A prospective study was conducted on 120 patients who underwent cataract surgery at the Phramongkutklao Hospital from September 2014 to October 2014. Conjunctival and lid margin swabs were obtained from patients before they underwent cataract surgery. These swabs were used to inoculate blood agar and chocolate agar plates for culturing. After growth of the normal flora, the antibiotic sensitivity method using tobramycin, moxifloxacin, levofloxacin, and cefazolin was applied. Normal flora of conjunctiva and lid margin, along with its antibiotic sensitivity, from patients who underwent cataract surgery was assessed. A total of 120 eyes were included in this study, and bacterial isolation rates were identified. Five bacteria from the lid margin were cultured, namely, coagulase-negative staphylococcus (58.33%), Streptococcus spp. (2.5%), Corynebacterium (1.67%), Micrococcus spp. (1.67%), and Staphylococcus aureus (0.83%). Two bacteria from the conjunctiva were cultured, namely, coagulase-negative staphylococcus (30%) and Streptococcus spp. (0.83%). Results of antibiotic sensitivity test showed that all isolated bacteria are sensitive to cefazolin 100%, tobramycin 98.67%, levofloxacin 100%, and moxifloxacin 100%. Coagulase-negative staphylococci are the most common bacteria isolated from conjunctiva and lid margin.

Have the organisms that cause breast abscess changed with time?--Implications for appropriate antibiotic usage in primary and secondary care.

PubMed

Dabbas, Natalie; Chand, Manish; Pallett, Ann; Royle, Gavin T; Sainsbury, Richard

2010-01-01

Many patients with breast abscess are managed in primary care. Knowledge of current trends in the bacteriology is valuable in informing antibiotic choices. This study reviews bacterial cultures of a large series of breast abscesses to determine whether there has been a change in the causative organisms during the era of increasing methicillin-resistant Staphylococcus aureus (MRSA). Analysis was undertaken of all breast abscesses treated in a single unit over 2003 - 2006, including abscess type, bacterial culture, antibiotic sensitivity and resistance patterns. One hundred and ninety cultures were obtained (32.8% lactational abscess, 67.2% nonlactational). 83% yielded organisms. Staphylococcus aureus was the commonest organism isolated (51.3%). Of these, 8.6% were MRSA. Other common organisms included mixed anaerobes (13.7%), and anaerobic cocci (6.3%). Lactational abscesses were significantly more likely to be caused by S. aureus (p < 0.05). Methicillin-resistant Staphylococcus aureus rates were not statistically different between lactational and nonlactational abscess groups. Appropriate antibiotic choices are of great importance in the community management of breast abscess. Ideally, microbial cultures should be obtained to institute targeted therapy but we recommend the continued use of flucloxacillin with or without metronidazole (or amoxicillin-clavulanate as a single preparation) as initial empirical therapy.

Prevalence, assessment, and antimicrobial resistance patterns of Salmonella from raw chicken eggs in Haramaya, Ethiopia.

PubMed

Kemal, Jelalu; Sibhat, Berhanu; Menkir, Sissay; Beyene, Desta

2016-11-24

The presence of antimicrobial-resistant Salmonella in poultry and poultry products, including eggs, is a global public health concern. This study aimed to estimate the levels and patterns of antimicrobial resistance of Salmonella from chicken eggs and assess consumers' raw egg consumption and farmers' handling practices. A total of 300 egg samples were collected from Haramaya open market (n = 150) and Haramaya University poultry farm (n = 150) in Ethiopia. Questionnaires were administered to egg sellers and buyers. A sterile cotton swab was used to sample the surface of eggs. The shells were sterilized and the egg content sampled. Isolation was done using the conventional methods for the detection of Salmonella, following the standard guidelines from ISO 6579. Sensitivity to 12 selected antibiotics was tested following the procedure of the Clinical and Laboratory Standards Institute. A level of 5.3% was observed among eggs shells from the open market and 0% among egg shells from the poultry farm, for an overall level of 2.7%. There was a significant difference (p = 0.004) between the prevalence of Salmonella spp. in sample site and sample type. Of the antimicrobials tested, Salmonella isolates were all resistant to erythromycin and clindamycin. Isolates were sensitive to ciprofloxacin (100%) and chloramphenicol (87.5%). All isolates were resistant to multiple antibiotics. One-third of the consumers were found to have eaten raw eggs for perceived medicinal values. To minimize the potential contamination of eggs by pathogens, the eggs should be properly handled, transported, and stored.

Antibiotic sensitivity and sequence amplification patterns of genes in multidrug resistant enterobacteria isolates from processed foods in some West African countries.

PubMed

Owoseni, Abimbola Adetokunboh; Onilude, Abiodun Anthony

2011-01-01

Diarrhoea, dysentery and other diseases due to other enteric bacteria have reportedly been found to resist chemotherapeutic treatment in some West African communities with fatal consequences in some cases. This study was carried out to determine multidrug resistance patterns of Enterobacteria isolates from processed ready-to-eat foods. Indigenously processed food samples of different types were collected from two Francophone and two Anglophone countries in the West African sub-region during the wet and dry seasons of a sampling period of two years. Enterobacteria were isolated from the samples using standard techniques. Amplification of chromosomal DNA of the isolates using the Polymerase Chain Reaction was carried out. The results obtained were subjected to statistical analyses. All isolates showed resistance to cefuroxime (90.7%), nitrofurantoin (90.6%), augmentin (86.1%) and ampicillin (51.2%) while all were sensitive to gentamycin and ciprofloxacin. There was amplification indicating the presence of invA gene at a position of 240 bp. There was no amplification at all for the spvC gene in any of the isolates tested. Multidrug resistant enteric bacteria in these foods containing the invA gene could lead to infections with uncontrolled antibiotic use. The presence of enteric bacteria in the foods analyzed which provide undeniable evidence of the poor microbiological quality of these foods could form the basis of a useful databank in formulation of food-borne disease control and prevention strategies.

Burn Wound Infections and Antibiotic Susceptibility Patterns at Pakistan Institute of Medical Sciences, Islamabad, Pakistan

PubMed Central

Saaiq, Muhammad; Ahmad, Shehzad; Zaib, Muhammad Salman

2015-01-01

BACKGROND Burn wound infections carry considerable mortality and morbidity amongst burn injury victims who have been successfully rescued through the initial resuscitation. This study assessed the prevalent microrganisms causing burn wound infections among hospitalized patients; their susceptibility pattern to commonly used antibiotics; and the frequency of infections with respect to the duration of the burn wounds. METHODS This study was carried out at Burn Care Centre, Pakistan Institute of Medical Sciences (PIMS), Islamabad, Pakistan over a period of two years (i.e. from June 2010 to May 2012). The study included all wound-culture-positive patients of either gender and all ages, who had sustained deep burns and underwent definitive management with wound excisions and skin auto-grafting. Patients with negative cultures of the wounds were excluded. Tissue specimens for culture and sensitivity were collected from burn wounds using standard collection techniques and analyzed at microbiological laboratory. RESULTS Out of a total of 95 positive microbial growths, 36 were Pseudomonas aeruginosa (35.29%) as the most frequent isolate found, followed by 21 Klebsiella pneumoniae (20.58%), 19 Staphylococcus aureaus (18.62%), 10 Proteus (9.80%), 7 E. coli (6.86%), 7 Acinetobacter (6.86%), and 4 Candida (3.92%). A variable antibiotic susceptibility pattern was observed among the grown microbes. Positive cultures were significantly more frequent among patients with over two weeks duration of burn wounds. CONCLUSION P. aeruginosa, K. pneumoniae and S. aureus constituted the most common bacterial microbes of burn wounds in our in-patients cases. Positive cultures were more frequent among patients with over two weeks duration of burn wounds. Early excision and skin grafting of deep burns and adherence to infection control measures can help to effectively reduce the burden of these infections. PMID:25606471

The biofilm-specific antibiotic resistance gene ndvB is important for expression of ethanol oxidation genes in Pseudomonas aeruginosa biofilms.

PubMed

Beaudoin, Trevor; Zhang, Li; Hinz, Aaron J; Parr, Christopher J; Mah, Thien-Fah

2012-06-01

Bacteria growing in biofilms are responsible for a large number of persistent infections and are often more resistant to antibiotics than are free-floating bacteria. In a previous study, we identified a Pseudomonas aeruginosa gene, ndvB, which is important for the formation of periplasmic glucans. We established that these glucans function in biofilm-specific antibiotic resistance by sequestering antibiotic molecules away from their cellular targets. In this study, we investigate another function of ndvB in biofilm-specific antibiotic resistance. DNA microarray analysis identified 24 genes that were responsive to the presence of ndvB. A subset of 20 genes, including 8 ethanol oxidation genes (ercS', erbR, exaA, exaB, eraR, pqqB, pqqC, and pqqE), was highly expressed in wild-type biofilm cells but not in ΔndvB biofilms, while 4 genes displayed the reciprocal expression pattern. Using quantitative real-time PCR, we confirmed the ndvB-dependent expression of the ethanol oxidation genes and additionally demonstrated that these genes were more highly expressed in biofilms than in planktonic cultures. Expression of erbR in ΔndvB biofilms was restored after the treatment of the biofilm with periplasmic extracts derived from wild-type biofilm cells. Inactivation of ethanol oxidation genes increased the sensitivity of biofilms to tobramycin. Together, these results reveal that ndvB affects the expression of multiple genes in biofilms and that ethanol oxidation genes are linked to biofilm-specific antibiotic resistance.

A survey on microorganisms and their sensitivity by E-test in ventilator-associated pneumonia at Toxicological-Intensive Care Unit of Loghman-Hakim Hospital.

PubMed

Talaie, Haleh; Sabeti, Shahram; Mahdavinejad, Arezou; Barari, Behjat; Kamalbeik, Sepideh

2010-12-01

Ventilator associated pneumonia (VAP) is the most common nosocomial infection at ICUs, with high mortality and morbidity. The diagnostic method for VAP is based on the combination of clinical, radiological, and microbiological criteria. Lower respiratory tract culture results are useful to confirm the etiology of VAP and adjusted antibiotics. Endotracheal aspiration (EA) is the simplest noninvasive technique for performing lower respiratory tract culture, with high sensitivity and moderately high specificity. The aim of this survey was to evaluate the quantitative cultures of endotracheal aspirates in VAP patients and the sensitivity patterns of microorganisms through E-test. Among 582 ICU admitted patients who were under mechanical ventilation for more than 48 hours, 72 suspected patients of VAP were prospectively evaluated during a 10 month period. Evaluation of our ICU standards by APACHE III scoring, and GCS were carried out on the first day of admission in all patients. Quantitative cultures of EA were performed on all 72 patients. Antibiotic resistance pattern of isolated pathogens was defined by E-test. VAP was confirmed in 46 out of 72 cases (50, 69.4% males and 22, 30.6% females - mean age was 33 +/- 12 years) through quantitative cultures of EA samples. The probable incidence of VAP was 7.9% (per ventilated patients > or = 48 hours). The mean APACHE III score was 31.28 +/- 16. GCS in most of the patients was between 8 and 12. Staphylococcus aureus was the most frequently isolated organism (58.7%), with high sensitivity to Amikacin, Ciprofloxacin, and Teicoplanin (>92%); Pseudomonas aeruginosa was the second most frequent organism (17.4 percent); Acinetobacter isolates were potentially drug resistant, and only Amikacin was effective. Tracheal aspirates in combination with clinical findings show important roles in the management of VAP and decrease inappropriate antimicrobial therapy. S. aureus is the main agent leading to VAP in the TICU of the Loghman Hakim Hospital.

Contribution of urinary tract infection to the burden of febrile illnesses in young children in rural Kenya

PubMed Central

O’Meara, Wendy Prudhomme; Holland, Thomas L.; Armstrong, Janice

2017-01-01

Introduction The clinical features of UTI in young children may not localize to the urinary tract and closely resemble other febrile illnesses. In malaria endemic areas, a child presenting with fever is often treated presumptively for malaria without investigation for UTI. Delayed or inadequate treatment of UTI increases the risk of bacteremia and renal scarring in young children and subsequently complications as hypertension and end stage renal disease in adulthood. Methods A cross-sectional study was carried out in a hospital in western Kenya. Inpatients and outpatients 2 months to five years with axillary temperature ≥37.5°C and no antibiotic use in the previous week were enrolled between September 2012 and April 2013. Urine dipstick tests, microscopy, and cultures were done and susceptibility patterns to commonly prescribed antibiotics established. UTI was defined as presence of pyuria (a positive urine dipstick or microscopy test) plus a positive urine culture. Results A total of 260 subjects were recruited; 45.8% were female and the median age was 25months (IQR: 13, 43.5). The overall prevalence of UTI was 11.9%. Inpatients had a higher prevalence compared to outpatients (17.9% v 7.8%, p = 0.027). UTI co-existed with malaria but the association was not significant (OR 0.80, p = 0.570). The most common organisms isolated were Escherichia coli (64.5%) and Staphylococcus aureus (12.9%) and were sensitive to ciproflaxin, cefuroxime, ceftriaxone, gentamycin and nitrofurantoin but largely resistant to more commonly used antibiotics such as ampicillin (0%), amoxicillin (16.7%), cotrimoxazole (16.7%) and amoxicillin-clavulinate (25%). Conclusion Our study demonstrates UTI contributes significantly to the burden of febrile illness in young children and often co-exists with other infections. Multi-drug resistant organisms are common therefore choice of antimicrobial therapy should be based on local sensitivity pattern. PMID:28323886

Contribution of urinary tract infection to the burden of febrile illnesses in young children in rural Kenya.

PubMed

Masika, Wechuli Geoffrey; O'Meara, Wendy Prudhomme; Holland, Thomas L; Armstrong, Janice

2017-01-01

The clinical features of UTI in young children may not localize to the urinary tract and closely resemble other febrile illnesses. In malaria endemic areas, a child presenting with fever is often treated presumptively for malaria without investigation for UTI. Delayed or inadequate treatment of UTI increases the risk of bacteremia and renal scarring in young children and subsequently complications as hypertension and end stage renal disease in adulthood. A cross-sectional study was carried out in a hospital in western Kenya. Inpatients and outpatients 2 months to five years with axillary temperature ≥37.5°C and no antibiotic use in the previous week were enrolled between September 2012 and April 2013. Urine dipstick tests, microscopy, and cultures were done and susceptibility patterns to commonly prescribed antibiotics established. UTI was defined as presence of pyuria (a positive urine dipstick or microscopy test) plus a positive urine culture. A total of 260 subjects were recruited; 45.8% were female and the median age was 25months (IQR: 13, 43.5). The overall prevalence of UTI was 11.9%. Inpatients had a higher prevalence compared to outpatients (17.9% v 7.8%, p = 0.027). UTI co-existed with malaria but the association was not significant (OR 0.80, p = 0.570). The most common organisms isolated were Escherichia coli (64.5%) and Staphylococcus aureus (12.9%) and were sensitive to ciproflaxin, cefuroxime, ceftriaxone, gentamycin and nitrofurantoin but largely resistant to more commonly used antibiotics such as ampicillin (0%), amoxicillin (16.7%), cotrimoxazole (16.7%) and amoxicillin-clavulinate (25%). Our study demonstrates UTI contributes significantly to the burden of febrile illness in young children and often co-exists with other infections. Multi-drug resistant organisms are common therefore choice of antimicrobial therapy should be based on local sensitivity pattern.

Antibiotic Sensitivity of Micrococcus radiodurans

PubMed Central

Hawiger, J.; Jeljaszewicz, J.

1967-01-01

A wild-type strain of Micrococcus radiodurans and its nonpigmented mutant W1 were tested for sensitivity to 10 antibiotics selected from the standpoint of their mechanism of action. Representatives of groups of antibiotics inhibiting deoxyribonucleic acid (DNA) synthesis, DNA-dependent ribonucleic acid synthesis, protein synthesis, and cell wall synthesis were selected. M. radiodurans and its mutant exhibited full susceptibility to all antibiotics tested (mitomycin C, actinomycin D, chloramphenicol, dihydrostreptomycin, erythromycin, neomycin, kanamycin, benzylpenicillin, bacitracin, and vancomycin), the degree of susceptibility being of the same order as that of a standard strain of Staphylococcus aureus 209 P, with the exception of dihydrostreptomycin. PMID:4166078

Management of neonatal sepsis at Muhimbili National Hospital in Dar es Salaam: diagnostic accuracy of C-reactive protein and newborn scale of sepsis and antimicrobial resistance pattern of etiological bacteria.

PubMed

Mkony, Martha Franklin; Mizinduko, Mucho Michael; Massawe, Augustine; Matee, Mecky

2014-12-05

We determined the accuracy of Rubarth's newborn scale of sepsis and C- reactive protein in diagnosing neonatal sepsis and assessed antimicrobial susceptibility pattern of etiological bacteria. This cross sectional study was conducted at Muhimbili National Hospital in Dar es Salaam, Tanzania between July 2012 and March 2013. Neonates suspected to have sepsis underwent physical examination using Rubarth's newborn scale of sepsis (RNSOS). Blood was taken for culture and antimicrobial sensitivity testing, full blood picture and C - reactive protein (CRP) performed 12 hours apart. The efficacy of RNSOS and serial CRP was assessed by calculating sensitivity, specificity, negative and positive predictive values, receiver operating characteristics (ROC) analysis as well as likelihood ratios (LHR) with blood culture result used as a gold standard. Out of 208 blood samples, 19.2% had a positive blood culture. Single CRP had sensitivity and specificity of 87.5% and 70.9% respectively, while RNSOS had sensitivity of 65% and specificity of 79.7%. Serial CRP had sensitivity of 69.0% and specificity of 92.9%. Combination of CRP and RNSOS increased sensitivity to 95.6% and specificity of 56.4%. Combination of two CRP and RNSOS decreased sensitivity to 89.1% but increased specificity to 74%. ROC for CRP was 0.86; and for RNSOS was 0.81. For CRP the LHR for positive test was 3 while for negative test was 0.18, while for RNSOS the corresponding values were 3.24 and for negative test was 0.43. Isolated bacteria were Klebsiella spp 14 (35%), Escherichia coli 12 (22.5%), Coagulase negative staphlococci 9 (30%), Staphylococcus aureus 4 (10%), and Pseudomonas spp 1 (2.5%). The overall resistance to the WHO recommended first line antibiotics was 100%, 92% and 42% for cloxacillin, ampicillin and gentamicin, respectively. For the second line drugs resistance was 45%, 40%, and 7% for ceftriaxone, vancomycin and amikacin respectively. Single CRP in combination with RNSOS can be used for rapid identification of neonates with sepsis due to high sensitivity (95.6%) but cannot exclude those without sepsis due to low specificity (56.4%). Serial CRP done 12hrs apart can be used to exclude non-cases. This study demonstrated very high levels of resistance to the first-line antibiotics.

Antibiotics: MedlinePlus Health Topic

MedlinePlus

... or not using them properly, can add to antibiotic resistance . This happens when bacteria change and become able ... ports Pseudomembranous colitis Sensitivity analysis Related Health Topics Antibiotic Resistance Bacterial Infections Medicines National Institutes of Health The ...

Antibiotic Sensitivity Profiling and Virulence Potential of Campylobacter jejuni Isolates from Estuarine Water in the Eastern Cape Province, South Africa.

PubMed

Otigbu, Anthony C; Clarke, Anna M; Fri, Justine; Akanbi, Emmanuel O; Njom, Henry A

2018-05-06

Campylobacter jejuni (CJ) is a zoonotic microbe and a major causative organism of diarrheal infection in humans that often has its functional characteristics inactivated in stressed conditions. The current study assessed the correlation between recovered CJ and water quality parameters and the drug sensitivity patterns of the pathogen to frontline antibiotics in human and veterinary medicine. Water samples ( n = 244) from rivers/estuarines were collected from April⁻September 2016, and physicochemical conditions were recorded on-site. CJ was isolated from the samples using standard microbiological methods and subjected to sensitivity testing to 10 antibiotics. Mean CJ counts were between 1 and 5 logs (CFU/mL). Ninety-five isolates confirmed as CJ by PCR showed varying rates of resistance. Sensitivity testing showed resistance to tetracycline (100%), azithromycin (92%), clindamycin (84.2%), clarithromycin and doxycycline (80%), ciprofloxacin (77.8%), vancomycin (70.5%), erythromycin (70%), metronidazole (36.8%) and nalidixic acid (30.5%). Virulence encoding genes were detected in the majority 80/95, 84.2%) of the confirmed isolates from cdtB ; 60/95 (63.2%) from cstII ; 49/95 (51.6%) from cadF ; 45/95 (47.4%) from clpP ; 30/95 (31.6%) from htrB , and 0/95 (0%) from csrA . A multiple resistance cme ABC active efflux pump system was present in 69/95 (72.6) isolates. The presence of CJ was positively correlated with temperature ( r = 0.17), pH ( r = 0.02), dissolved oxygen ( r = 0.31), and turbidity ( r = 0.23) but negatively correlated with salinity ( r = −0.39) and conductivity ( r = −0.28). The detection of multidrug resistant CJ strains from estuarine water and the differential gene expressions they possess indicates a potential hazard to humans. Moreover, the negative correlation between the presence of the pathogen and physicochemical parameters such as salinity indicates possible complementary expression of stress tolerance response mechanisms by wild-type CJ strains.

Diversity and Antibiotic Resistance Patterns of Sphingomonadaceae Isolates from Drinking Water▿

PubMed Central

Vaz-Moreira, Ivone; Nunes, Olga C.; Manaia, Célia M.

2011-01-01

Sphingomonadaceae (n = 86) were isolated from a drinking water treatment plant (n = 6), tap water (n = 55), cup fillers for dental chairs (n = 21), and a water demineralization filter (n = 4). The bacterial isolates were identified based on analysis of the 16S rRNA gene sequence, and intraspecies variation was assessed on the basis of atpD gene sequence analysis. The isolates were identified as members of the genera Sphingomonas (n = 27), Sphingobium (n = 28), Novosphingobium (n = 12), Sphingopyxis (n = 7), and Blastomonas (n = 12). The patterns of susceptibility to five classes of antibiotics were analyzed and compared for the different sites of isolation and taxonomic groups. Colistin resistance was observed to be intrinsic (92%). The highest antibiotic resistance prevalence values were observed in members of the genera Sphingomonas and Sphingobium and for beta-lactams, ciprofloxacin, and cotrimoxazole. In tap water and in water from dental chairs, antibiotic resistance was more prevalent than in the other samples, mainly due to the predominance of isolates of the genera Sphingomonas and Sphingobium. These two genera presented distinct patterns of association with antibiotic resistance, suggesting different paths of resistance development. Antibiotic resistance patterns were often related to the species rather than to the site or strain, suggesting the importance of vertical resistance transmission in these bacteria. This is the first study demonstrating that members of the family Sphingomonadaceae are potential reservoirs of antibiotic resistance in drinking water. PMID:21705522

Factors influencing antibiotic prescribing habits and use of sensitivity testing amongst veterinarians in Europe.

PubMed

De Briyne, N; Atkinson, J; Pokludová, L; Borriello, S P; Price, S

2013-11-16

The Heads of Medicines Agencies and the Federation of Veterinarians of Europe undertook a survey to gain a better insight into the decision-making process of veterinarians in Europe when deciding which antibiotics to prescribe. The survey was completed by 3004 practitioners from 25 European countries. Analysis was to the level of different types of practitioner (food producing (FP) animals, companion animals, equines) and country for Belgium, Czech Republic, France, Germany, Spain, Sweden and the UK. Responses indicate no single information source is universally considered critical, though training, published literature and experience were the most important. Factors recorded which most strongly influenced prescribing behaviour were sensitivity tests, own experience, the risk for antibiotic resistance developing and ease of administration. Most practitioners usually take into account responsible use warnings. Antibiotic sensitivity testing is usually performed where a treatment failure has occurred. Significant differences were observed in the frequency of sensitivity testing at the level of types of practitioners and country. The responses indicate a need to improve sensitivity tests and services, with the availability of rapid and cheaper testing being key factors.

Factors influencing antibiotic prescribing habits and use of sensitivity testing amongst veterinarians in Europe

PubMed Central

De Briyne, N.; Atkinson, J.; Pokludová, L.; Borriello, S. P.; Price, S.

2013-01-01

The Heads of Medicines Agencies and the Federation of Veterinarians of Europe undertook a survey to gain a better insight into the decision-making process of veterinarians in Europe when deciding which antibiotics to prescribe. The survey was completed by 3004 practitioners from 25 European countries. Analysis was to the level of different types of practitioner (food producing (FP) animals, companion animals, equines) and country for Belgium, Czech Republic, France, Germany, Spain, Sweden and the UK. Responses indicate no single information source is universally considered critical, though training, published literature and experience were the most important. Factors recorded which most strongly influenced prescribing behaviour were sensitivity tests, own experience, the risk for antibiotic resistance developing and ease of administration. Most practitioners usually take into account responsible use warnings. Antibiotic sensitivity testing is usually performed where a treatment failure has occurred. Significant differences were observed in the frequency of sensitivity testing at the level of types of practitioners and country. The responses indicate a need to improve sensitivity tests and services, with the availability of rapid and cheaper testing being key factors. PMID:24068699

[Sensitivity and antibiotic resistance in infections of the musculoskeletal system].

PubMed

Mata-Hernández, Argenis; Rivera-Villa, Adrián Huematzin; Miguel-Pérez, Adrián; Pérez-Atanasio, José Manuel; Torres-González, Rubén

2016-01-01

Infections of the musculoskeletal system are a devastating complication for patients, due to it's long rehabilitation process and even sometimes the removal of the implant, the chronicity of infection, is often due to lack of coverage in empirical antibiotics. A retrospective, observational, descriptive cohort study was performed. All cultures form musculoskeletal system infected patients reported of sensitivity and resistance of germs isolated were analyzed. A total of 143 positive results were included. Reported more frequent germ Staphylococcus aureus accounted for 75 positive cases, followed by Escherichia coli with 31 positive results. Antibiotics with better sensitivity according to the type of microorganisms were trimethoprim-sulfamethoxazole and vancomycin, levofloxacin and linezolid, gentamicin, erythromycin and amikacin. Regarding antibiotic resistance, those reported with the highest percentage were penicillin G, amoxicillin with clavulanic acid and ampicillin. We recommend using empirical treatments in musculoskeletal system infections, trimethoprim-sulfamethoxazole are the best choice because they have the same sensitivity compare with vancomycin and a resistance rate of 7.6%. Betalactamics have a high percentage of resistance and low sensitivity so we must consider alternatives.

Epidemiology of urinary tract infections and antibiotics sensitivity among pregnant women at Khartoum North Hospital.

PubMed

Hamdan, Hamdan Z; Ziad, Abdel Haliem M; Ali, Salah K; Adam, Ishag

2011-01-18

Urinary tract infections (UTI) can lead to poor maternal and perinatal outcomes. Investigating epidemiology of UTI and antibiotics sensitivity among pregnant women is fundamental for care-givers and health planners. A cross sectional study has been conducted at Khartoum north teaching hospital Antenatal Care Clinic between February-June 2010, to investigate epidemiology of UTI and antibiotics resistance among pregnant women. Structured questionnaires were used to gather data from pregnant women. UTI was diagnosed using mid stream urine culture on standard culture media Out of 235 pregnant women included, 66 (28.0%) were symptomatic and 169 (71.9%) asymptomatic. the prevalence of bacteriuria among symptomatic and asymptomatic pregnant women were (12.1%), and (14.7%) respectively, with no significant difference between the two groups (P = 0.596), and the overall prevalence of UTI was (14.0%). In multivariate analyses, age, gestational age, parity, and history of UTI in index pregnancy were not associated with bacteriuria. Escherichia coli (42.4%) and S. aureus (39.3%) were the commonest isolated bacteria. Four, 2, 2, 3, 4, 2 and 0 out of 14 E. coli isolates, showed resistance to amoxicillin, naladixic acid, nitrofurantoin, ciprofloxacin, co-trimoxazole, amoxicillin/clavulanate and norfloxacin, respectively. Escherichia coli were the most prevalent causative organisms and showing multi drug resistance pattern, asymptomatic bacteriuria is more prevalent than symptomatic among pregnant women. Urine culture for screening and diagnosis purpose for all pregnant is recommended.

Extended spectrum beta lactamase producing organisms causing urinary tract infections in Sri Lanka and their antibiotic susceptibility pattern -A hospital based cross sectional study.

PubMed

Fernando, M M P S C; Luke, W A N V; Miththinda, J K N D; Wickramasinghe, R D S S; Sebastiampillai, B S; Gunathilake, M P M L; Silva, F H D S; Premaratna, R

2017-02-10

Extended Spectrum Beta- Lactamase producing organisms causing urinary tract infections (ESBL-UTI) are increasing in incidence and pose a major burden to health care. While ESBL producing Klebsiella species seem to account for most nosocomial outbreaks, ESBL-producing E. coli have been isolated from both hospitalized and non-hospitalized patients. Although 95-100% ESBL organisms are still considered sensitive to meropenem, rapid emergence of carbapenem resistance has been documented in many countries. The objective of this study was to evaluate urinary tract infections caused by ESBL producers and the antibiotic susceptibility patterns in Sri Lanka. Patients with confirmed ESBL-UTI admitted to Professorial Medical Unit, Colombo North Teaching Hospital from January - June 2015 were recruited to the study. Their urine culture and antibiotic susceptibility reports were evaluated after obtaining informed written consent. Of 61 culture positive ESBL-UTIs, E. coli caused 53 (86.8%), followed by Klebsiella in 8 (13.1%).30 (49.1%) had a history of hospitalization within the past three months and included 6/8(75%) of Klebsiella UTI and 24/53(45.2%) of E.coli UTI. Antibiotic susceptibility of ESBL organisms were; Meropenem 58 (95%), Imipenem 45 (73.7%), Amikacin 37 (60.6%) and Nitrofurantoin 28(45.9%). In 3(4.9%), E.coli were resistant to Meropenem. These three patients had received multiple antibiotics including meropenem in the recent past for recurrent UTI. We observed a higher percentage of E. coli over Klebsiella as ESBL producing organisms suggesting most ESBL-UTIs to be community acquired, Carbapenems seem to remain as the first line therapy for majority of ESBL-UTIs in the local setting. However 4.9% prevalence of meropenem resistance is alarming compared to other countries. Although prior antibiotic utilization and hospitalization may contribute to emergence of ESBL producing Klebsiella and E.coli in Sri Lanka, high prevalence of community acquired ESBL-E. coli needs further investigations to identify potential causes . Being a third world country with a free health care system, observed alarming rate of carbapenem resistance is likely to add a significant burden to health budget. We feel that treatment of infections in general needs a careful approach adhering to recommended antibiotic guidelines in order to prevent emergence of multi drug resistant organisms.

UTI diagnosis and antibiogram using Raman spectroscopy

NASA Astrophysics Data System (ADS)

Kastanos, Evdokia; Kyriakides, Alexandros; Hadjigeorgiou, Katerina; Pitris, Constantinos

2009-07-01

Urinary tract infection diagnosis and antibiogram require a 48 hour waiting period using conventional methods. This results in ineffective treatments, increased costs and most importantly in increased resistance to antibiotics. In this work, a novel method for classifying bacteria and determining their sensitivity to an antibiotic using Raman spectroscopy is described. Raman spectra of three species of gram negative Enterobacteria, most commonly responsible for urinary tract infections, were collected. The study included 25 samples each of E.coli, Klebsiella p. and Proteus spp. A novel algorithm based on spectral ratios followed by discriminant analysis resulted in classification with over 94% accuracy. Sensitivity and specificity for the three types of bacteria ranged from 88-100%. For the development of an antibiogram, bacterial samples were treated with the antibiotic ciprofloxacin to which they were all sensitive. Sensitivity to the antibiotic was evident after analysis of the Raman signatures of bacteria treated or not treated with this antibiotic as early as two hours after exposure. This technique can lead to the development of new technology for urinary tract infection diagnosis and antibiogram with same day results, bypassing urine cultures and avoiding all undesirable consequences of current practice.

Antibiotic use in acute cholecystitis: practice patterns in the absence of evidence-based guidelines.

PubMed

Kanafani, Zeina A; Khalifé, Nadine; Kanj, Souha S; Araj, George F; Khalifeh, Mohammad; Sharara, Ala I

2005-08-01

Antibiotics are frequently administered in acute cholecystitis for preoperative prophylaxis or postoperative treatment. The optimal timing, choice, and duration of antibiotics are unclear. We conducted a retrospective review of all cases of acute cholecystitis between 1996 and 2001 at the American University of Beirut Medical Centre. A survey among general surgeons was also performed to describe the pattern of antibiotic prescribing in uncomplicated acute cholecystitis. A MEDLINE search for guidelines for antibiotic use in acute cholecystitis was conducted. The number of cases of acute cholecystitis was 79. The mean duration of postoperative antibiotic therapy was 5 days. There was no correlation between the severity of symptoms, gallbladder description, or positive gallbladder culture and the use of antibiotics postoperatively. Sixty five percent of interviewed surgeons would continue antibiotic therapy postoperatively for 3 or more days. Search of the medical literature failed to provide clear guidelines for antibiotic use in acute cholecystitis. The use of antibiotics in patients with acute cholecystitis is erratic and costly. Prospective studies are needed to better study the effectiveness of a short course of antibiotics in uncomplicated cases. The role of gallbladder culture in guiding antibiotic therapy should be defined as routine cultures add to the cost without evident benefit.

Competitive Growth Enhances Conditional Growth Mutant Sensitivity to Antibiotics and Exposes a Two-Component System as an Emerging Antibacterial Target in Burkholderia cenocepacia.

PubMed

Gislason, April S; Choy, Matthew; Bloodworth, Ruhi A M; Qu, Wubin; Stietz, Maria S; Li, Xuan; Zhang, Chenggang; Cardona, Silvia T

2017-01-01

Chemogenetic approaches to profile an antibiotic mode of action are based on detecting differential sensitivities of engineered bacterial strains in which the antibacterial target (usually encoded by an essential gene) or an associated process is regulated. We previously developed an essential-gene knockdown mutant library in the multidrug-resistant Burkholderia cenocepacia by transposon delivery of a rhamnose-inducible promoter. In this work, we used Illumina sequencing of multiplex-PCR-amplified transposon junctions to track individual mutants during pooled growth in the presence of antibiotics. We found that competition from nontarget mutants magnified the hypersensitivity of a clone underexpressing gyrB to novobiocin by 8-fold compared with hypersensitivity measured during clonal growth. Additional profiling of various antibiotics against a pilot library representing most categories of essential genes revealed a two-component system with unknown function, which, upon depletion of the response regulator, sensitized B. cenocepacia to novobiocin, ciprofloxacin, tetracycline, chloramphenicol, kanamycin, meropenem, and carbonyl cyanide 3-chlorophenylhydrazone, but not to colistin, hydrogen peroxide, and dimethyl sulfoxide. We named the gene cluster esaSR for enhanced sensitivity to antibiotics sensor and response regulator. Mutational analysis and efflux activity assays revealed that while esaS is not essential and is involved in antibiotic-induced efflux, esaR is an essential gene and regulates efflux independently of antibiotic-mediated induction. Furthermore, microscopic analysis of cells stained with propidium iodide provided evidence that depletion of EsaR has a profound effect on the integrity of cell membranes. In summary, we unraveled a previously uncharacterized two-component system that can be targeted to reduce antibiotic resistance in B. cenocepacia. Copyright © 2016 American Society for Microbiology.

Complete urinary tract infection (UTI) diagnosis and antibiogram using surface enhanced Raman spectroscopy (SERS)

NASA Astrophysics Data System (ADS)

Hadjigeorgiou, Katerina; Kastanos, Evdokia; Kyriakides, Alexandros; Pitris, Costas

2012-03-01

There are three stages to a complete UTI diagnosis: (1) identification of a urine sample as positive/negative for an infection, (2) identification of the responsible bacterium, (3) antibiogram to determine the antibiotic to which the bacteria are most sensitive to. Using conventional methods, all three stages require bacterial cultures in order to provide results. This long delay in diagnosis causes a rise in ineffective treatments, chronic infections, health care costs and antibiotic resistance. In this work, SERS is used to identify a sample as positive/negative for a UTI as well as to obtain an antibiogram against different antibiotics. SERS spectra of serial dilutions of E. coli bacteria mixed with silver nanoparticles, showed a linear correlation between spectral intensity and concentration. For antibiotic sensitivity testing, SERS spectra of three species of gram negative bacteria were collected four hours after exposure to the antibiotics ciprofloxacin and amoxicillin. Spectral analysis revealed clear separation between bacterial samples exposed to antibiotics to which they were sensitive and samples exposed to antibiotics to which they were resistant. With the enhancement provided by SERS, the technique can be applied directly to urine samples leading to the development of a new, rapid method for UTI diagnosis and antibiogram.

Effects of ten antibiotics on seed germination and root elongation in three plant species.

PubMed

Hillis, Derek G; Fletcher, James; Solomon, Keith R; Sibley, Paul K

2011-02-01

We applied a screening-level phytotoxicity assay to evaluate the effects of 10 antibiotics (at concentrations ranging from 1 to 10,000 μg/L) on germination and early plant growth using three plant species: lettuce (Lactuca sativa), alfalfa (Medicago sativa), and carrot (Daucus carota). The range of phytotoxicity of the antibiotics was large, with EC₂₅s ranging from 3.9 μg/L to >10,000 μg/L. Chlortetracycline, levofloxacin, and sulfamethoxazole were the most phytotoxic antibiotics. D. carota was the most sensitive plant species, often by an order of magnitude or more, followed by L. sativa and then M. sativa. Plant germination was insensitive to the antibiotics, with no significant decreases up to the highest treatment concentration of 10,000 μg/L. Compared with shoot and total length measurements, root elongation was consistently the most sensitive end point. Overall, there were few instances where measured soil concentrations, if available in the publicly accessible literature, would be expected to exceed the effect concentrations of the antibiotics evaluated in this study. The use of screening assays as part of a tiered approach for evaluating environmental impacts of antibiotics can provide insight into relative species sensitivity and serve as a basis by which to screen the potential for toxic effects of novel compounds to plants.

Prophylactic antibiotic use in pediatric patients undergoing urinary tract catheterization: a survey of members of the Society for Pediatric Urology.

PubMed

Glaser, Alexander P; Rosoklija, Ilina; Johnson, Emilie K; Yerkes, Elizabeth B

2017-09-06

Current organizational guidelines regarding use of antibiotics during urinary tract catheterization are based on limited evidence and are not directly applicable to the pediatric urology population. We seek to improve understanding of this population by first evaluating current practices. This study aims to investigate practice patterns and attitudes of pediatric urologists regarding the use of antibiotics in the setting of urinary tract catheterization. An online survey was sent to members of the Society for Pediatric Urology. Questionnaire sections included demographics, general questions about antibiotic use with catheterization, and specific clinical scenarios. Descriptive statistics were used, and chi-square analysis was performed to examine associations between demographics and specific responses. Of 448 pediatric urologists surveyed, 154 (34%) responded to the survey. A majority of surveyed urologists (78%) prescribe daily prophylactic antibiotics with a hypospadias stent in place, but extensive variation in use of antibiotics was reported with other catheters and tubes. Extensive variation in practice patterns was also reported for three case scenarios regarding antibiotic prophylaxis with catheterization. Urologists > 50 years of age and fellowship-trained urologists were more likely to prescribe antibiotics for hypospadias stents (p = 0.02, p = 0.03), but no other significant associations between demographic characteristics and antibiotic use were found. There is substantial variation in practice patterns among surveyed pediatric urologists regarding prophylactic antibiotic use with urinary catheterization. This variation, combined with a lack of objective data and increasing pressure to decrease infectious complications and combat antibiotic resistance, highlights the need for development of management guidelines for this unique population.

Antimicrobial resistance profile of urinary tract infection at a secondary care hospital in Medan, Indonesia

NASA Astrophysics Data System (ADS)

Rahimi, A.; Saragih, R. H.; Nainggolan, R.

2018-03-01

Urinary tract infection (UTI) is a considerable health problem which ranks as the second leading cause of infection after respiratory tract one. Antimicrobial resistance in UTI has become a burden in the management of the disease due to high usage of antibiotics. A comprehensive understanding of the etiology and the antimicrobial resistance of the uropathogenic bacteria is essential to provide adequate treatment. This study aims to determine the etiologic agents and their susceptibility pattern in UTI patients. The analysis was performed retrospectively on culture isolates obtained from urine samples received at the Department of Microbiology, Dr.Pirngadi General Hospital, Medan, Indonesia in the period from January 2015 until December 2016. Higher prevalence of UTI was found in female participants of the study in comparison with males. Enterobacter (64.58%) was the most common bacteria revealed as the etiologic agent, followed by E. coli (11.46%), Citrobacter and Klebsiella (9.38% each). Amikacin and meropenem were the most sensitive antimicrobial agents for Enterobacter, E. coli, Citrobacter, and Klebsiella, showing low resistance rate. This study showed that Enterobacter was the most dominant bacterial pathogen of UTI. Amikacin and meropenem were the antibiotics with high sensitivity for UTI treatment.

Selective advantage of resistant strains at trace levels of antibiotics: a simple and ultrasensitive color test for detection of antibiotics and genotoxic agents.

PubMed

Liu, Anne; Fong, Amie; Becket, Elinne; Yuan, Jessica; Tamae, Cindy; Medrano, Leah; Maiz, Maria; Wahba, Christine; Lee, Catherine; Lee, Kim; Tran, Katherine P; Yang, Hanjing; Hoffman, Robert M; Salih, Anya; Miller, Jeffrey H

2011-03-01

Many studies have examined the evolution of bacterial mutants that are resistant to specific antibiotics, and many of these focus on concentrations at and above the MIC. Here we ask for the minimum concentration at which existing resistant mutants can outgrow sensitive wild-type strains in competition experiments at antibiotic levels significantly below the MIC, and we define a minimum selective concentration (MSC) in Escherichia coli for two antibiotics, which is near 1/5 of the MIC for ciprofloxacin and 1/20 of the MIC for tetracycline. Because of the prevalence of resistant mutants already in the human microbiome, allowable levels of antibiotics to which we are exposed should be below the MSC. Since this concentration often corresponds to low or trace levels of antibiotics, it is helpful to have simple tests to detect such trace levels. We describe a simple ultrasensitive test for detecting the presence of antibiotics and genotoxic agents. The test is based on the use of chromogenic proteins as color markers and the use of single and multiple mutants of Escherichia coli that have greatly increased sensitivity to either a wide range of antibiotics or specific antibiotics, antibiotic families, and genotoxic agents. This test can detect ciprofloxacin at 1/75 of the MIC.

High prevalence of multiple resistance to antibiotics in Salmonella serovars isolated from a poultry slaughterhouse in Spain.

PubMed

Carramiñana, Juan J; Rota, Carmina; Agustín, I; Herrera, Antonio

2004-11-30

Salmonellosis is a major foodborne infection in Spain, and strains that are resistant to a great variety of antibiotics have become a major public health concern. The aim of this study was to determine the level of antibiotic resistance in 133 Salmonella isolates obtained from a poultry slaughterhouse in Zaragoza (NE Spain). Antimicrobial resistance testing was performed by disk diffusion method using 19 antibiotics. Results were interpreted following the NCCLS criteria. Overall, the highest percentage of resistance was found to the following antimicrobial agents: sulfadiazine (96.2%), neomycin (53.4%), tetracycline (21.8%), and streptomycin (11.3%). All isolates were found to be resistant to one or more of the antibiotics tested. Multiple resistance was observed in 87 strains (65.4%). We found 23 different patterns of resistance in Salmonella Enteritidis. Resistance to sulfadiazine was the most common single resistance. The most frequent patterns of multiresistant strains were neomycin+sulfadiazine and neomycin+tetracycline+sulfadiazine. S. 4,5,12:b: showed the highest percentages of resistance to the tested drugs, with five different resistance patterns found. Ampicillin+chloramphenicol+streptomycin+sulphonamides+tetracycline (ACSSuT) resistance pattern, commonly associated with S. Typhimurium DT 104, was not detected in strains of the same phage type from broilers. The appearance of substantial multiresistance in foodborne Salmonella isolates suggests the need for more prudent use of antibiotics by farmers, veterinarians, and physicians.

Lab on a chip sensor for rapid detection and antibiotic resistance determination of Staphylococcus aureus.

PubMed

Abeyrathne, Chathurika D; Huynh, Duc H; Mcintire, Thomas W; Nguyen, Thanh C; Nasr, Babak; Zantomio, Daniela; Chana, Gursharan; Abbott, Iain; Choong, Peter; Catton, Mike; Skafidas, Efstratios

2016-03-21

The Gram-positive bacterium, Staphylococcus aureus (S. aureus), is a major pathogen responsible for a variety of infectious diseases ranging from cellulitis to more serious conditions such as septic arthritis and septicaemia. Timely treatment with appropriate antibiotic therapy is essential to ensure clinical defervescence and to prevent further complications such as infective endocarditis or organ impairment due to septic shock. To date, initial antibiotic choice is empirical, using a "best guess" of likely organism and sensitivity- an approach adopted due to the lack of rapid identification methods for bacteria. Current culture based methods take up to 5 days to identify the causative bacterial pathogen and its antibiotic sensitivity. This paper provides proof of concept for a biosensor, based on interdigitated electrodes, to detect the presence of S. aureus and ascertain its sensitivity to flucloxacillin rapidly (within 2 hours) in a cost effective manner. The proposed method is label-free and uses non-faradic measurements. This is the first study to successfully employ interdigitated electrodes for the rapid detection of antibiotic resistance. The method described has important potential outcomes of faster definitive antibiotic treatment and more rapid clinical response to treatment.

[Identification of lactic acid bacteria in commercial yogurt and their antibiotic resistance].

PubMed

Qin, Yuxuan; Li, Jing; Wang, Qiuya; Gao, Kexin; Zhu, Baoli; Lv, Na

2013-08-04

To identify lactic acid bacteria (LAB) in commercial yogurts and investigate their antibiotic resistance. LABs were cultured from 5 yogurt brands and the isolates were identified at the species level by 16S rRNA sequence. Genotyping was performed by repetitive extragenic palindromic PCR (rep-PCR). The sensitivity to 7 antibiotics was tested for all LAB isolates by Kirby-Bauer paper diffusion (K-B method). Meanwhile, 9 antibiotic resistance genes (ARGs), including erythromycin resistance genes (ermA and ermB) and tetracycline resistance genes (tetM, tetK, tetS, tetQ, tetO, tetL and tetW), were detected by PCR amplification in the identified LAB isolates. The PCR products were confirmed by sequencing. Total 100 LABs were isolated, including 23 Lactobacillus delbrueckii ssp. bulgaricus, 26 Lactobacillus casei, 30 Streptococcus thermophilus, 5 Lactobacillus acidophilus, 6 Lactobacillus plantarum, and 10 Lactobacillus paracasei. The drug susceptibility test shows that all 100 isolates were resistant to gentamicin and streptomycin, 42 isolates were resistant to vancomycin, and on the contrary all were sensitive to cefalexin, erythromycin, tetracycline and oxytetracycline. Moreover, 5 ARGs were found in the 28 sequencing confirmed isolates, ermB gene was detected in 8 isolates, tet K in 4 isolates, tetL in 2 isolates, tetM in 4 isolates, tetO in 2 isolates. erm A, tet S, tet Q and tet W genes were not detected in the isolates. Antibiotic resistance genes were found in 53.57% (15/28) sequenced isolates, 2 -3 antibiotic resistance genes were detected in 4 isolates of L. delbrueckii ssp. bulgaricus. Some LABs were not labeled in commercial yogurt products. Antibiotic resistance genes tend to be found in the starter culture of L. delbrueckii ssp. Bulgaricus and S. thermophilus. All the LAB isolates were sensitive to erythromycin and tetracycline, even though some carried erythromycin and/or tetracycline resistance genes. We proved again that LAB could carry antibiotic resistance gene(s) though it is sensitive to antibiotics.

Extrachromosomal DNA length and antibiograms of Staphylococcus aureus and Pseudomonas aeruginosa isolated from tears of HIV/AIDS patients after curing with sodium dodecyl sulphate.

PubMed

Ajayi, B O; Otajevwo, F D

2012-01-01

Staphylococcus aureus and Pseudomonas aeruginosa strains were isolated from eye swab samples randomly obtained from 100 seropositive HIV/AIDS patients who reported to various anti-retroviral treatment clinics at the University of Benin Teaching Hospital and Central Hospital both based in Benin City, Nigeria. Invitro antibiotic sensitivity patterns of strains before curing were determined by the Kirby-Bauer disc diffusion technique. Resistance plasmid DNA of multidrug resistant strains was cured with 0.1% sodium dodecyl sulphate and cured strains were again subjected to in vitro antibiotic sensitivity testing. EcoRI and Hind III restriction endonuclease enzymes were used to make cuts on extracted plasmid DNA whose length sizes were then determined. A total of 36 (36.0%) strains made up of 27 (75.0%) Staphylococcus. aureus and 9 (25.0%) Pseudomonas aeruginosa were isolated of which 7 (19.4%) strains showed multidrug resistance to ciprofloxacin, pefloxacin, ofloxacine, gentamycin, tetracycline, ampicillin, chloramphenicol, nitrofurantoin and erythromycin. All seven multidrug resistant strains before curing, recorded 85.7%, 42.9%, 14.3% and 14.3% sensitivity in that decreasing order to ciprofloxacin, pefloxacin, ofloxacin and gentamycin respectively. There was 0.0% sensitivity each to tetracycline and ampicillin. After curing, there was enhanced sensitivity of 100.0%, 85.7%, 28.6% and 71.4% respectively. There was also 28.6% and 57.1% improved sensitivity to tetracycline and ampicillin after curing. Before curing, there was 76.2% average resistance to all used antibiotics and this reduced to 47.6% after curing Staph. aureus plasmid DNA. In the case of Pseudomonas aeruginosa, there was an average resistance of 76.3% before curing which fell to 42.5% after curing. EcoRI restriction enzyme gave the plasmid DNA length of Staphylococcus aureus strain 04 as 4.0Kb and this size depended upon the distance between recognition sites. Isolation of 36 (36.0%) strains of both isolates from 100 eye swabs shows the danger these organisms portend to all categories of opticians. The cheapness and high sensitivity of gentamycin justifies its use as eye drops for treatment of some eye infections. Curing of plasmid DNA is an indication that if SDS is administered to the organisms in sublethal doses, it can lead to the elimination of plasmid DNA without adverse effect on the genomic DNA of the bacterial strains.

Extrachromosomal DNA Length and Antibiograms of Staphylococcus aureus and Pseudomonas aeruginosa Isolated from Tears of HIV/AIDS Patients after Curing with Sodium Dodecyl Sulphate

PubMed Central

B. O., Ajayi; F. D., Otajevwo

2012-01-01

Staphylococcus aureus and Pseudomonas aeruginosa strains were isolated from eye swab samples randomly obtained from 100 seropositive HIV/AIDS patients who reported to various anti-retroviral treatment clinics at the University of Benin Teaching Hospital and Central Hospital both based in Benin City, Nigeria. Invitro antibiotic sensitivity patterns of strains before curing were determined by the Kirby-Bauer disc diffusion technique. Resistance plasmid DNA of multidrug resistant strains was cured with 0.1% sodium dodecyl sulphate and cured strains were again subjected to invitro antibiotic sensitivity testing. EcoRI and Hind III restriction endonuclease enzymes were used to make cuts on extracted plasmid DNA whose length sizes were then determined. A total of 36 (36.0%) strains made up of 27 (75.0%) Staphylococcus. aureus and 9 (25.0%) Pseudomonas aeruginosa were isolated of which 7 (19.4%) strains showed multidrug resistance to ciprofloxacin, pefloxacin, ofloxacine, gentamycin, tetracycline, ampicillin, chloramphenicol, nitrofurantoin and erythromycin. All seven multidrug resistant strains before curing, recorded 85.7%, 42.9%, 14.3% and 14.3% sensitivity in that decreasing order to ciprofloxacin, pefloxacin, ofloxacin and gentamycin respectively. There was 0.0% sensitivity each to tetracycline and ampicillin. After curing, there was enhanced sensitivity of 100.0%, 85.7%, 28.6% and 71.4% respectively. There was also 28.6% and 57.1% improved sensitivity to tetracycline and ampicillin after curing. Before curing, there was 76.2% average resistance to all used antibiotics and this reduced to 47.6% after curing Staph. aureus plasmid DNA. In the case of Pseudomonas aeruginosa, there was an average resistance of 76.3% before curing which fell to 42.5% after curing. EcoRI restriction enzyme gave the plasmid DNA length of Staphylococcus aureus strain 04 as 4.0Kb and this size depended upon the distance between recognition sites. Isolation of 36 (36.0%) strains of both isolates from 100 eye swabs shows the danger these organisms portend to all categories of opticians. The cheapness and high sensitivity of gentamycin justifies its use as eye drops for treatment of some eye infections. Curing of plasmid DNA is an indication that if SDS is administered to the organisms in sublethal doses, it can lead to the elimination of plasmid DNA without adverse effect on the genomic DNA of the bacterial strains. PMID:22980121

Antimicrobial sensitivity--A natural resource to be protected by a Pigouvian tax?

PubMed

Vågsholm, Ivar; Höjgård, Sören

2010-08-01

Since their discovery more than 70 years ago antibiotic drugs have been efficient tools for treating bacterial infections, and their use has reduced the number of fatalities and the suffering from bacterial diseases. However, the use of antibiotics may lead to resistance to the same or other antibiotics. The risk of resistance appears to be larger in veterinary medicine, since antibiotics have been given as feed-additives in animal production, the amounts given are larger, and the risk of selecting the wrong antibiotic is higher due to lack of diagnostic facilities. Historically, as resistance developed, new classes of antibiotics were developed, but today however, the flow of new substances has slowed. The resistance that arises from antibiotic use is a negative externality or a cost that is not included in the price of antibiotics since it affects the public good of antibiotic sensitivity. The negative externality implies that antibiotic consumption becomes too high. Antibiotic use can be restricted by e.g., prohibiting the use in animal feeding stuffs, prescription only use, or banning the use for animals or by using economic incentives, but restrictions on antibiotic use could have negative effects on the development of new antimicrobials since restrictions might reduce the profitability of such efforts to the pharmaceutical industry. It is therefore of interest to see what economic theory can contribute towards a solution. The objective of this study is to examine if a Pigouvian tax is an option for balancing the externalities and incentives for veterinary drug use. However, as a practical solution, it is suggested to use the costs of developing new antibiotics for determining the tax. The magnitude the tax based on European Union numbers ranges between 29 and 287euro per kilogram active substance or between 9 and 86% of the average price of commonly used antibiotics depending on the foreseen period in years (1-10 years) between the development of a new antibiotic drug. Hence, the sensitivity of bacteria to antibiotics should be managed as a finite natural resource. A tax based on the expected costs of development new antibiotic substances may offer a practical option for balancing the incentives and externalities of antibiotic use and development. Copyright 2010 Elsevier B.V. All rights reserved.

Antibiotic resistance of Vibrio parahaemolyticus isolated from coastal seawater and sediment in Malaysia

NASA Astrophysics Data System (ADS)

Drais, Ashraf Abbas; Usup, Gires; Ahmad, Asmat

2016-11-01

Vibrio parahaemolyticus is widely recognized pathogenic Vibrio species due to numerous outbreaks and its' wide occurrence in the marine environment. A total of 50 Vibrio parahaemolyticus isolates were isolated from seawater and sediments in Malaysia were tested for sensitivity to 19 antibiotics using disc diffusion method. It was found that all isolates were resistant towards ampicillin (10 μg), penicillin (10 μg), methicillin (5 μg), and novobiocin (5 μg); but exhibit sensitivity to chloramphenicol (30 μg) and gentamicin (100 μg). The low percentage of sensitivity towards antibiotics was observed with the following antibiotics; amoxicillin 10μg (98%), fluconazole 25μg (98%), erythromycin 15 μg (92%), vancomycin 30 μg (92%), bacitracin 10 μg (84%), carbenicillin 100 μg (84%), cephalothin 30 μg (52%), nitrofurantion 200 μg (52%), ciprofloxacin 5 μg (40%), tetracycline 30 μg (20%), kanamycin 30 μg (10%), nalidixic acid 30 μg (10%) and streptomycin 20 μg (6%). Multiple antibiotic resistance (MAR) index was found to be 0.42-0.78. All the isolates were multi-resistant to these antibiotics. This indicates that the isolates originate from high-risk source of contamination where antibiotics are often used. Thus, there is a need for supervised use of antibiotics and frequent surveillance of V. parahaemolyticus strains for antimicrobial resistance. The presence of V. parahaemolyticus in coastal water with a high value of multiple antibiotic resistance indexes (MARI) can increase the risk of exposure to human and regular monitoring program for this potential human pathogenic bacterium is important.

Mobile Display of Information about Aggregated Antibiotic Resistance in the Hospital Setting Supported by Near Field Communication.

PubMed

Meng, Philipp; Fehre, Karsten; Rappelsberger, Andrea; Adlassnig, Klaus-Peter

2014-01-01

Antibiotic resistance is a heterogeneous phenomenon. It does not only differ between countries or states, but also between wards of hospitals, where different resistance patterns have been found. To support clinicians in administering empiric antibiotic therapy, we developed software to present information about antibiotic resistance using a mobile concept. A pre-existing infrastructure was deployed as the server component. The systems analyze and aggregate data from laboratory information systems, generating statistical data on antibiotic resistance. The information is presented to the Android client using a Representational State Transfer (REST) interface. Geographical localization is performed using near field communication (NFC) tags. The prototype provides tabulated data concerning antibiotic resistance patterns in the wards of a hospital. Using Android, NFC, and data caching, the usability of the system is estimated to be high. We hypothesize that antibiotic stewardship in hospitals can be supported by this software, thus improving medical monitoring of antibiotic resistance. Future studies in a productive environment are needed to measure the impact of the system on the outcome of patient care.

[Sensitivity of meningococci to the antagonistic activity of nasopharyngeal microflora and antibiotics].

PubMed

Bochkov, I A; Larina, L I

1977-12-01

Comparative study of the meningococcus sensitivity of various serological groups with different localization in the human organism to the antagonistic activity of normal microbes of the nasopharynx and the antibiotics it was found that strains isolated from the cerebrospinal fluid of patients suffering from cerebrospinal meningitis, chiefly of serological group A, had the greatest resistance to the antagonists. Taking into consideration the leading epidemiological role of the cultures belonging to the serological group A in the USSR, it can be supposed that meningococcus sensitivity to the nasopharyngeal antagonists was of significance for the manifestation of their pathogenic properties. No association of the antibiotic sensitivity of the same strains with reference to a definite serological group or the site of the microbe localization was revealed.

Bacteriological Profile of Isolates From Urine Samples in Patients of Benign Prostatic Hyperplasia and or Prostatitis Showing Lower Urinary Tract Symptoms.

PubMed

Mishra, Prem Prakash; Prakash, Ved; Singh, Kashmir; Mog, H; Agarwal, Sumit

2016-10-01

The incidence of Benign Prostatic Hyperplasia (BPH) or Prostatitis is increasing considerably worldwide. The Lower Urinary Tract Symptoms (LUTS) due to bacterial aetiology are one of the common factors for the complications among the patients. To determine the bacterial agents and their antibiotic sensitivity pattern from the urine samples of patients of BPH or Prostatitis showing symptoms of LUTS. The cross-sectional study was carried out in the Department of Microbiology of Rohilkhand Medical College and Hospital of Northern India from June 2014 to May 2015. A total of 105 urine specimens from patients of BPH and/ or Prostatitis were cultured by a semi-quantitative method. The isolated bacteria were identified by colony morphology, Gram's staining, motility and biochemical tests. Antibiotic sensitivity was done according to the CLSI 2007 guidelines by disc diffusion method. Data was analysed by SPSS and Microsoft office 2007. Proportions and percentages were used as statistical measures. The urine cultures from patients with BPH and or chronic Prostatitis, showed n=66/105 (62.85%) culture positivity. Out of 66 isolates the frequency was in following order Escherichia coli 21/66 (31.81%), Klebsiella spp 19/66 (28.78%), Staphylococcus aureus 11/66 (16.66%), Pseudomonas aeruginosa (10.60%), Proteus spp, Enterococcus spp, Acinetobacter spp and Citrobacter spp. The most susceptible 1 st , 2 nd and 3 rd line antibiotics for Gram negative isolates were ampicillin, amikacin and tigecycline respectively. Amongst the Gram positive isolates, the susceptible 1 st , 2 nd and 3 rd line antibiotics were cefoxitin, vancomycin, teicoplanin and linezolid. Multidrug resistance was seen in Escherichia coli (n=6), Klebsiella spp (n=7), Pseudomonas aeruginosa (n=4) and Staphylococcus aureus (n=3). Based on the above findings we can say that accurate aetiology of the LUTS among the patients of BPH and/or Prostatitis is warranted to initiate the therapeutic management. Based on our study we state that the prime pathogens are E.coli , Klebsiella among Gram negative isolates and S. aureus among Gram positive. The most sensitive drugs are aminoglycosides, tetracyclines and carbepenems for Gram neagtive isolates and oxazolidinones and glycopeptides among Gram positive isolates.

Fighting antibiotic resistance in Portuguese hospitals: Understanding antibiotic prescription behaviours to better design antibiotic stewardship programmes.

PubMed

Simões, Alexandra S; Alves, Daniela A; Gregório, João; Couto, Isabel; Dias, Sónia; Póvoa, Pedro; Viveiros, Miguel; Gonçalves, Luzia; Lapão, Luís V

2018-06-01

Since physicians play an important role in antibiotic usage, it is vital to understand their antibiotic-prescribing behaviour and knowledge on antimicrobial resistance in order to develop and implement effective antibiotic stewardship interventions. The aim of this study was to evaluate Portuguese physicians' knowledge and to understand prescription behaviours, difficulties and barriers in their antibiotic prescription process in order to promote better and well-adapted antibiotic stewardship policies. This study was conducted in 2016 using a self-administered questionnaire to physicians in two tertiary public hospitals from two different regions in Portugal. Participating physicians [response rate 47.6% (30/63)] identified antibiotic resistance as a global problem; however, one-third did not recognise antibiotic resistance as a major problem on their own hospital. Factors that most influenced antibiotic prescription were 'microbiology laboratory results', 'patient clinical situation' and patient 'co-morbidities'. On the other hand, 'colleagues' opinion' and 'costs control' were considered as less determining factors. Regarding difficulties and bottlenecks in the antibiotic prescription process, participant physicians reported 'lack of (or delayed) microbiological results' and 'no access to antibiotic susceptibility patterns' as major barriers. 'Education and training' was considered the most effective intervention to improve antibiotic prescription. These results suggest that the design and implementation of antibiotic stewardship interventions should provide better data management and sharing tools between physicians and the microbiology laboratory, especially through the creation of antimicrobial prescribing guidelines according to hospital epidemiology, and easy access to hospital antibiotic susceptibility patterns and epidemiological data. Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Antibiotic susceptibility profiling and virulence potential of Campylobacter jejuni isolates from different sources in Pakistan.

PubMed

Siddiqui, Fariha Masood; Akram, Muhammad; Noureen, Nighat; Noreen, Zobia; Bokhari, Habib

2015-03-01

To determine antibiotic resistance patterns and virulence potential of Campylobacter jejuni (C. jejuni) isolates from clinical human diarrheal infections, cattle and healthy broilers. Antibiotic sensitivity patterns of C. jejuni isolates were determined by Kirby Bauer Disc Diffusion assay. These isolates were then subjected to virulence profiling for the detection of mapA (membrane-associated protein), cadF (fibronectin binding protein), wlaN (beta-l,3-galactosyltransferase) and neuAB (sialic acid biosynthesis gene). Further C. jejuni isolates were grouped by random amplification of polymorphic DNA (RAPD) profiling. A total of 436 samples from poultry (n=88), cattle (n=216) and humans (n=132) from different locations were collected. Results revealed percentage of C. jejuni isolates were 35.2% (31/88), 25.0% (54/216) and 11.3% (15/132) among poultry, cattle and clinical human samples respectively. Antibiotic susceptibility results showed that similar resistance patterns to cephalothin was ie. 87.0%, 87.1% and 89%among humans, poultry and cattle respectively, followed by sulfamethoxazole+trimethoprim 40.0%, 38.7% and 31.0% in humans, poultry and cattle and Ampicillin 40%, 32% and 20% in humans, poultry and cattle respectively. Beta-lactamase activity was detected in 40.00% humans, 20.37% cattle and 32.25% in poultry C. jejuni isolates. CadF and mapA were present in all poultry, cattle and human C. jejuni isolates, wlaN was not detected in any isolate and neuAB was found in 9/31 (36%) poultry isolates. RAPD profiling results suggested high diversity of C. jejuni isolates. Detection of multidrug resistant C. jejuni strains from poultry and cattle is alarming as they can be potential hazard to humans. Moreover, predominant association of virulence factors, cadF and mapA (100% each) in C. jejuni isolates from all sources and neuAB (36%) with poultry isolates suggest the potential source of transmission of diverse types of C. jejuni to humans. Copyright © 2015 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

Assessment of Antibiotic Susceptibility within Lactic Acid Bacteria and Coagulase-Negative Staphylococci Isolated from Hunan Smoked Pork, a Naturally Fermented Meat Product in China.

PubMed

Wang, Jing; Wei, Xinyuan; Fan, Mingtao

2018-06-01

The aim of this study was to evaluate the antibiotic susceptibility of lactic acid bacteria (LAB) and coagulase-negative staphylococci (CNS) strains isolated from naturally fermented smoked pork produced in Hunan, China. A total of 48 strains were isolated by selective medium and identified at the species level by 16S rRNA gene sequencing as follows: Staphylococcus carnosus (23), Lactobacillus plantarum (12), Lactobacillus brevis (10), Lactobacillus sakei (1), Weissella confusa (1), and Weissella cibaria (1). All strains were typed by RAPD-PCR, and their susceptibility to 15 antibiotics was determined and expressed as the minimum inhibitory concentration (MIC) using agar dilution method. High resistance to penicillin G, streptomycin, gentamycin, vancomycin, chloramphenicol, norfloxacin, ciprofloxacin, kanamycin, and neomycin was found among the isolates. All the strains were sensitive to ampicillin, while the susceptibility to tetracycline, oxytetracycline, erythromycin, lincomycin, and roxithromycin varied. The presence of relevant resistance genes was investigated by PCR and sequencing, with the following genes detected: str(A), str(B), tet(O), tet(M), ere(A), and catA. Eleven strains, including 3 S. carnosus, 6 L. plantarum, and 2 L. brevis, harbored more than 3 antibiotic resistance genes. Overall, multiple antibiotic resistance patterns were widely observed in LAB and S. carnosus strains isolated from Hunan smoked pork. Risk assessment should be carried out with regard to the safe use of LAB and CNS in food production. We evaluated the antibiotic resistance of lactic acid bacteria and coagulase-negative staphylococci strains isolated from Chinese naturally fermented smoked pork. Our results may provide important data on establishing breakpoint standards for LAB and CNS and evaluating the safety risk of these strains for commercial use. © 2018 Institute of Food Technologists®.

Multidrug resistance in pediatric urinary tract infections.

PubMed

Gaspari, Romolo J; Dickson, Eric; Karlowsky, James; Doern, Gary

2006-01-01

Urinary tract infections (UTIs) represent a common infection in the pediatric population. Escherichia coli is the most common uropathogen in children, and antimicrobial resistance in this species complicates the treatment of pediatric UTIs. Despite the impact of resistance on empiric antibiotic choice, there is little data on multidrug resistance in pediatric patients. In this paper, we describe characteristics of multidrug-resistant E. coli in pediatric patients using a large national database of uropathogens antimicrobial sensitivities. Antimicrobial susceptibility patterns to commonly prescribed antibiotics were performed on uropathogens isolated from children presenting to participating hospitals between 1999 and 2001. Data were analyzed separately for four pediatric age groups. Single and multidrug resistance to ampicillin, amoxicillin-clavulanate, cefazolin, ciprofloxacin, nitrofurantoin, and trimethoprim-sulfamethoxazole (TMP-SMX) were performed on all specimens. There were a total of 11,341 E. coli urine cultures from 343 infants (0-4 weeks), 1,801 toddlers (5 weeks-24 months), 6,742 preteens (2-12 years), and 2,455 teens (13-17 years). E. coli resistance to ampicillin peaked in toddlers (52.8%) but was high in preteens (52.1%), infants (50.4%), and teens (40.6%). Resistance to two or more antibiotics varied across age groups, with toddlers (27%) leading preteens (23.1%), infants (21%), and teens (15.9%). Resistance to three or more antibiotics was low in all age groups (range 3.1-5.2%). The most common co-resistance in all age groups was ampicillin/TMP-SMZ. In conclusion, less than half of all pediatric UTIs are susceptible to all commonly used antibiotics. In some age groups, there is a significant percentage of co-resistance between the two most commonly used antibiotics (ampicillin and TMP-SMZ).

Highly sensitive bacterial susceptibility test against penicillin using parylene-matrix chip.

PubMed

Park, Jong-Min; Kim, Jo-Il; Song, Hyun-Woo; Noh, Joo-Yoon; Kang, Min-Jung; Pyun, Jae-Chul

2015-09-15

This work presented a highly sensitive bacterial antibiotic susceptibility test through β-lactamase assay using Parylene-matrix chip. β-lactamases (EC 3.5.2.6) are an important family of enzymes that confer resistance to β-lactam antibiotics by catalyzing the hydrolysis of these antibiotics. Here we present a highly sensitive assay to quantitate β-lactamase-mediated hydrolysis of penicillin into penicilloic acid. Typically, MALDI-TOF mass spectrometry has been used to quantitate low molecular weight analytes and to discriminate them from noise peaks of matrix fragments that occur at low m/z ratios (m/z<500). The β-lactamase assay for the Escherichia coli antibiotic susceptibility test was carried out using Parylene-matrix chip and MALDI-TOF mass spectrometry. The Parylene-matrix chip was successfully used to quantitate penicillin (m/z: [PEN+H](+)=335.1 and [PEN+Na](+)=357.8) and penicilloic acid (m/z: [PA+H](+)=353.1) in a β-lactamase assay with minimal interference of low molecular weight noise peaks. The β-lactamase assay was carried out with an antibiotic-resistant E. coli strain and an antibiotic-susceptible E. coli strain, revealing that the minimum number of E. coli cells required to screen for antibiotic resistance was 1000 cells for the MALDI-TOF mass spectrometry/Parylene-matrix chip assay. Copyright © 2015 Elsevier B.V. All rights reserved.

CRISPR/Cas9-Mediated Re-Sensitization of Antibiotic-Resistant Escherichia coli Harboring Extended-Spectrum β-Lactamases.

PubMed

Kim, Jun-Seob; Cho, Da-Hyeong; Park, Myeongseo; Chung, Woo-Jae; Shin, Dongwoo; Ko, Kwan Soo; Kweon, Dae-Hyuk

2016-02-01

Recently, the clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (CRISPR/Cas9) system, a genome editing technology, was shown to be versatile in treating several antibiotic-resistant bacteria. In the present study, we applied the CRISPR/ Cas9 technology to kill extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. ESBL bacteria are mostly multidrug resistant (MDR), and have plasmid-mediated antibiotic resistance genes that can be easily transferred to other members of the bacterial community by horizontal gene transfer. To restore sensitivity to antibiotics in these bacteria, we searched for a CRISPR/Cas9 target sequence that was conserved among >1,000 ESBL mutants. There was only one target sequence for each TEM- and SHV-type ESBL, with each of these sequences found in ~200 ESBL strains of each type. Furthermore, we showed that these target sequences can be exploited to re-sensitize MDR cells in which resistance is mediated by genes that are not the target of the CRISPR/Cas9 system, but by genes that are present on the same plasmid as target genes. We believe our Re-Sensitization to Antibiotics from Resistance (ReSAFR) technology, which enhances the practical value of the CRISPR/Cas9 system, will be an effective method of treatment against plasmid-carrying MDR bacteria.

Validation of antibiotic residue tests for dairy goats.

PubMed

Zeng, S S; Hart, S; Escobar, E N; Tesfai, K

1998-03-01

The SNAP test, LacTek test (B-L and CEF), Charm Bacillus sterothermophilus var. calidolactis disk assay (BsDA), and Charm II Tablet Beta-lactam sequential test were validated using antibiotic-fortified and -incurred goat milk following the protocol for test kit validations of the U.S. Food and Drug Administration Center for Veterinary Medicine. SNAP, Charm BsDA, and Charm II Tablet Sequential tests were sensitive and reliable in detecting antibiotic residues in goat milk. All three assays showed greater than 90% sensitivity and specificity at tolerance and detection levels. However, caution should be taken in interpreting test results at detection levels. Because of the high sensitivity of these three tests, false-violative results could be obtained in goat milk containing antibiotic residues below the tolerance level. Goat milk testing positive by these tests must be confirmed using a more sophisticated methodology, such as high-performance liquid chromatography, before the milk is condemned. LacTek B-L test did not detect several antibiotics, including penicillin G, in goat milk at tolerance levels. However, LacTek CEF was excellent in detecting ceftiofur residue in goat milk.

Antibacterial effect of mango (Mangifera indica Linn.) leaf extract against antibiotic sensitive and multi-drug resistant Salmonella typhi.

PubMed

Hannan, Abdul; Asghar, Samra; Naeem, Tahir; Ikram Ullah, Muhammad; Ahmed, Ijaz; Aneela, Syeda; Hussain, Shabbir

2013-07-01

Alternative herbal medicine has been used to treat various infections from centuries. Natural plants contain phytoconstituents having similar chemical properties as of synthetic antibiotics. Typhoid fever is a serious infection and failure of its treatment emerged multi-drug resistant (MDR) bugs of Salmonella typhi. Due to multiple and repeated issues with antibiotics efficacy, it became essential to evaluate biological properties of plants from different geographical origins. Mango leaves have been Reported for various medicinal effects like antioxidant, antimicrobial, antihelminthic, antidiabetic and antiallergic etc. Objective of present study was to investigate anti-typhoid properties of acetone mango leaf extract (AMLE) against antibiotic sensitive and MDR S. typhi isolates. A total of 50 isolates of S. typhi including MDR (n=30) and antibiotic sensitive (n=20) were investigated. Staphylococcus aureus (ATCC 25923) and Salmonella typhimurium (ATCC14028) were used as quality control strains. AMLE was prepared and its antibacterial activity was evaluated by agar well diffusion screening method and minimum inhibitory concentration (MIC), by agar dilution technique. Zone of inhibition (mm) of AMLE against MDR and antibiotic sensitive isolates was 18±1.5mm (Mean±S.D). Zone of S. aureus (ATCC 25923) and S. typhimurium (ATCC14028) was 20±1.5mm (Mean±S.D). MIC of AMLE was Reported in range from 10-50 mg/ml. The present study described the inhibitory effects of mango leaves against S. typhi.

Modeling cooperating micro-organisms in antibiotic environment.

PubMed

Book, Gilad; Ingham, Colin; Ariel, Gil

2017-01-01

Recent experiments with the bacteria Paenibacillus vortex reveal a remarkable strategy enabling it to cope with antibiotics by cooperating with a different bacterium-Escherichia coli. While P. vortex is a highly effective swarmer, it is sensitive to the antibiotic ampicillin. On the other hand, E. coli can degrade ampicillin but is non-motile when grown on high agar percentages. The two bacterial species form a shared colony in which E. coli is transported by P. vortex and E. coli detoxifies the ampicillin. The paper presents a simplified model, consisting of coupled reaction-diffusion equations, describing the development of ring patterns in the shared colony. Our results demonstrate some of the possible cooperative movement strategies bacteria utilize in order to survive harsh conditions. In addition, we explore the behavior of mixed colonies under new conditions such as antibiotic gradients, synchronization between colonies and possible dynamics of a 3-species system including P. vortex, E. coli and a carbon producing algae that provides nutrients under illuminated, nutrient poor conditions. The derived model was able to simulate an asymmetric relationship between two or three micro-organisms where cooperation is required for survival. Computationally, in order to avoid numerical artifacts due to symmetries within the discretizing grid, the model was solved using a second order Vectorizable Random Lattices method, which is developed as a finite volume scheme on a random grid.

Modeling cooperating micro-organisms in antibiotic environment

PubMed Central

Book, Gilad; Ingham, Colin; Ariel, Gil

2017-01-01

Recent experiments with the bacteria Paenibacillus vortex reveal a remarkable strategy enabling it to cope with antibiotics by cooperating with a different bacterium—Escherichia coli. While P. vortex is a highly effective swarmer, it is sensitive to the antibiotic ampicillin. On the other hand, E. coli can degrade ampicillin but is non-motile when grown on high agar percentages. The two bacterial species form a shared colony in which E. coli is transported by P. vortex and E. coli detoxifies the ampicillin. The paper presents a simplified model, consisting of coupled reaction-diffusion equations, describing the development of ring patterns in the shared colony. Our results demonstrate some of the possible cooperative movement strategies bacteria utilize in order to survive harsh conditions. In addition, we explore the behavior of mixed colonies under new conditions such as antibiotic gradients, synchronization between colonies and possible dynamics of a 3-species system including P. vortex, E. coli and a carbon producing algae that provides nutrients under illuminated, nutrient poor conditions. The derived model was able to simulate an asymmetric relationship between two or three micro-organisms where cooperation is required for survival. Computationally, in order to avoid numerical artifacts due to symmetries within the discretizing grid, the model was solved using a second order Vectorizable Random Lattices method, which is developed as a finite volume scheme on a random grid. PMID:29284016

Reducing the volume of antibiotic prescriptions: a peer group intervention among physicians serving a community with special ethnic characteristics.

PubMed

Wilf-Miron, Rachel; Ron, Naama; Ishai, Shlomit; Chory, Hana; Abboud, Louis; Peled, Ronit

2012-05-01

Antibiotics are a front-line weapon against many infectious diseases. However, antibiotic overuse is the key driver of drug resistance. Previously published studies have suggested benefits of using peer-to-peer education, working with group leaders to build trust and maintain confidentiality within a quality initiative. We hypothesized that working with physicians as a peer group might be beneficial in influencing antibiotic prescribing patterns. To describe and evaluate a peer group model for an intervention to reduce the volume of antibiotic prescriptions among physicians with above average prescribing rates serving an Arab community in northern Israel. Primary care physicians in a defined geographic area who served Arab communities and had high antibiotic prescribing rates--defined as above average number of antibiotic prescriptions per office visit compared with regional and organizational averages--were recruited for the intervention. All other physicians from the same region served as a comparison group. The intervention was administered during 2007 and was completed in early 2008. Four structured meetings scheduled 2 months apart, in which the group explored the issues related to antibiotic overuse, included the following topics: adherence to clinical guidelines; the special position physicians serving Arab communities hold and the influence it has on their practices; pressure due to consumer demands; and suggestions for possible strategies to face ethnic sensitivity, mainly because of the special ties the physicians have with their communities. T-tests for independent samples were used to perform between-group comparisons for each quarter and year of observation from 2006 through 2010, and t-tests for paired samples were used to compare pre-intervention with post-intervention antibiotic prescribing rates. In the 2006 pre-intervention period, the antibiotic prescribing rates were 0.17 for the peer group (n = 11 physicians) and 0.15 for the comparison group (n = 72 physicians, P = 0.279). In 2008 following the intervention, rates were 0.12 and 0.14, respectively (P = 0.396). In the paired t-test analysis, rates declined significantly from 2006 to 2008 in the intervention group (P < 0.001) but not in the comparison group (P = 0.138). Antibiotic prescribing rates remained similar in 2009 and 2010. In the context of a community with special ethnic and cultural characteristics, an intervention relying on peer group techniques was associated with a modest reduction in the volume of antibiotic prescriptions.

Typhoid outbreak in Songkhla, Thailand 2009-2011: clinical outcomes, susceptibility patterns, and reliability of serology tests.

PubMed

Limpitikul, Wannee; Henpraserttae, Narong; Saksawad, Rachanee; Laoprasopwattana, Kamolwish

2014-01-01

To determine the clinical manifestations and outcomes, the reliability of Salmonella enterica serotype Typhi (S ser. Typhi) IgM and IgG rapid tests, and the susceptibility patterns and the response to treatment during the 2009-2011 typhoid outbreak in Songkhla province in Thailand. The medical records of children aged <15 years with S ser. Typhi bacteremia were analysed. The efficacy of the typhoid IgM and IgG rapid tests and susceptibility of the S ser. Typhi to the current main antibiotics used for typhoid (amoxicillin, ampicillin, cefotaxime, ceftriaxone, co-trimoxazole, and ciprofloxacin), were evaluated. S ser. Typhi bacteremia was found in 368 patients, and all isolated strains were susceptible to all 6 antimicrobials tested. Most of the patients were treated with ciprofloxacin for 7-14 days. The median time (IQR) of fever before treatment and duration of fever after treatment were 5 (4, 7) days and 4 (3, 5) days, respectively. Complications of ascites, lower respiratory symptoms, anemia (Hct <30%), and ileal perforation were found in 7, 7, 22, and 1 patients, respectively. None of the patients had recurrent infection or died. The sensitivities of the typhoid IgM and IgG tests were 58.3% and 25.6% respectively, and specificities were 74.1% and 50.5%, respectively. Most of the patients were diagnosed at an early stage and treated with a good outcome. All S ser. Typhi strains were susceptible to standard first line antibiotic typhoid treatment. The typhoid IgM and IgG rapid tests had low sensitivity and moderate specificity.

Antimicrobial susceptibility pattern in diabetic foot ulcer: a pilot study.

PubMed

Sekhar, Sm; Vyas, N; Unnikrishnan, Mk; Rodrigues, Gs; Mukhopadhyay, C

2014-09-01

Diabetic foot infections (DFIs) are major public health problems and knowledge of microbes that cause infections are helpful to determine proper antibiotic therapy. The aim was to investigate the antimicrobial susceptibility pattern of microbes in DFIs. A cross-sectional study was conducted for a period of 6 months at the Department of General Surgery, KMC hospital, Manipal University, Manipal, India. During this period, 108 patients having DFIs admitted in the general surgery wards were tracked from the hospital data management system. These patients' pus samples were examined as Gram-stained smear and cultured aerobically on blood agar and MacConkey agar plates. Antimicrobial susceptibility test was performed by disc diffusion techniques according to Clinical and Laboratory Standards Institute guidelines. Of the 108 specimens of the diabetic foot lesions, culture showed polymicrobial growth in 44.4% (48/108). Prevalence of Gram-negative organisms (56%, 84/150) was found to be more than Gram-positive organisms (44%, 66/150). However, Staphylococcus aureus was the most frequent pathogen (28%, 42/150). All Gram-positive aerobes were sensitive to doxycycline. All Gram-negative isolates, including extended spectrum beta lactamase producing strains of Proteus mirabilis and Klebsiella oxytoca except Acinetobacter were highly sensitive to amikacin, cefoperazone/sulbactam, and meropenem. Acinetobacter was completely resistant to all the common antibiotics tested. Prevalence showed Gram-negative bacteria was slightly more than Gram-positive bacteria in diabetic foot ulcers. This study recommends doxycycline should be empirical treatment of choice for Gram-positive isolates and amikacin, cefoperazone/sulbactam, and meropenem should be considered for most of the Gram-negatives aerobes.

Point prevalence survey of antibiotic use and resistance at a referral hospital in Kenya: findings and implications.

PubMed

Okoth, Caleb; Opanga, Sylvia; Okalebo, Faith; Oluka, Margaret; Baker Kurdi, Amanj; Godman, Brian

2018-04-27

A substantial amount of antibiotic use in hospitals may be inappropriate, potentially leading to the development and spread of antibiotic resistance, adverse effects, mortality and increased hospital costs. The objective was to assess current patterns of antibiotic use in a leading referral hospital in Western Kenya. This would lead to the identification of opportunities for quality improvement in this hospital and others across Kenya. A point prevalence survey was carried out with data abstracted principally from patient medical records supplemented by interviews from physicians when needed. The pattern of antibiotic use was analyzed by descriptive methods. Differences in antibiotic use and indications between the selected wards were compared using the Chi-square test or Fisher's exact tests. Among the patients surveyed, 67.7% were on antibiotics. The most common classes of antibiotics prescribed were third generation cephalosporins (55%), imidazole derivatives like metronidazole (41.8%) and broad spectrum penicillins (41.8%). The most common indication for antibiotic use was medical prophylaxis (29%), with local guidelines advocating antibiotic prophylaxis in mothers after delivery of their child as well as in neonates with birth asphyxia and low weight at birth. Dosing of antibiotics was seen as generally optimal when assessed against current recommendations. Whilst the dosing of antibiotics seemed adequate, there was high use of antibiotics in this hospital. This needs to be urgently reviewed with currently appreciable empiric antibiotic use. Programmes are being instigated to address these concerns. This includes developing antibiotic guidelines and formularies especially for empiric use as well as implementing antimicrobial stewardship activities.

Aerobic microbiology and culture sensitivity of head and neck space infection of odontogenic origin

PubMed Central

Shah, Amit; Ramola, Vikas; Nautiyal, Vijay

2016-01-01

Context: Head and neck space infections source, age, gender, tooth involved, fascial spaces involved, microbiological study of aerobic flora, and antibiotic susceptibilities. Aims: The aim of the present study is to identify causative aerobic microorganisms responsible for deep fascial spaces of head and neck infections and evaluate the resistance of antibiotics used in the treatment of such. Settings and Design: Prospective study in 100 patients. Materials and Methods: This prospective study was conducted on 100 patients who reported in the outpatient department and fulfilled the inclusion criteria to study aerobic microbiology and antibiotic sensitivity in head and neck space infection of odontogenic origin. Pus sample was obtained either by aspiration or by swab stick from the involved spaces, and culture and sensitivity tests were performed. Statistical Analysis Used: Chi-square test and level of significance. Results: Result showed aerobic Gram-positive isolates were 73% and aerobic Gram-negative isolates were 18%. Nine percent cases showed no growth. Streptococcus viridans was the highest isolate in 47% cases among Gram-positive bacteria, and in Gram-negative, Klebsiella pneumoniae was the highest isolate of total cases 11%. Amoxicillin showed resistance (48.4%) as compared to other antibiotics such as ceftriaxone, carbenicillin, amikacin, and imipenem had significantly higher sensitivity. Conclusions: Amoxicillin with clavulanic acid showed (64.8%) efficacy for all organisms isolated, whereas ceftriaxone showed (82.4%) efficacy and could be used in odontogenic infections for both Gram-positive and Gram-negative microorganisms. Substitution of third generation cephalosporin for amoxicillin in the empirical management of deep fascial space infections can also be used. Carbenicillin, amikacin, and imipenem showed (93.4%) sensitivity against all microorganisms and should be reserved for more severe infection. Newer and broad-spectrum antibiotics are more effective in vitro than older narrow spectrum antibiotics. PMID:28163480

Long-Term Exposure of Agricultural Soil to Veterinary Antibiotics Changes the Population Structure of Symbiotic Nitrogen-Fixing Rhizobacteria Occupying Nodules of Soybeans (Glycine max).

PubMed

Revellin, Cécile; Hartmann, Alain; Solanas, Sébastien; Topp, Edward

2018-05-01

Antibiotics are entrained in agricultural soil through the application of manures from medicated animals. In the present study, a series of small field plots was established in 1999 that receive annual spring applications of a mixture of tylosin, sulfamethazine, and chlortetracycline at concentrations ranging from 0.1 to 10 mg · kg -1 soil. These antibiotics are commonly used in commercial swine production. The field plots were cropped continuously for soybeans, and in 2012, after 14 annual antibiotic applications, the nodules from soybean roots were sampled and the occupying bradyrhizobia were characterized. Nodules and isolates were serotyped, and isolates were distinguished using 16S rRNA gene and 16S to 23S rRNA gene intergenic spacer region sequencing, multilocus sequence typing, and RSα fingerprinting. Treatment with the antibiotic mixture skewed the population of bradyrhizobia dominating the nodule occupancy, with a significantly larger proportion of Bradyrhizobium liaoningense organisms even at the lowest dose of 0.1 mg · kg -1 soil. Likewise, all doses of antibiotics altered the distribution of RSα fingerprint types. Bradyrhizobia were phenotypically evaluated for their sensitivity to the antibiotics, and there was no association between in situ treatment and a decreased sensitivity to the drugs. Overall, long-term exposure to the antibiotic mixture altered the composition of bradyrhizobial populations occupying nitrogen-fixing nodules, apparently through an indirect effect not associated with the sensitivity to the drugs. Further work evaluating agronomic impacts is warranted. IMPORTANCE Antibiotics are entrained in agricultural soil through the application of animal or human waste or by irrigation with reused wastewater. Soybeans obtain nitrogen through symbiotic nitrogen fixation. Here, we evaluated the impact of 14 annual exposures to antibiotics commonly used in swine production on the distribution of bradyrhizobia occupying nitrogen-fixing nodules on soybean roots in a long-term field experiment. By means of various sequencing and genomic fingerprinting techniques, the repeated exposure to a mixture of tylosin, sulfamethazine, and chlortetracycline each at a nominal soil concentration of 0.1 mg · kg -1 soil was found to modify the diversity and identity of bradyrhizobia occupying the nodules. Nodule occupancy was not associated with the level of sensitivity to the antibiotics, indicating that the observed effects were not due to the direct toxicity of the antibiotics on bradyrhizobia. Altogether, these results indicate the potential for long-term impacts of antibiotics on this agronomically important symbiosis. © Crown copyright 2018.

Selected Heat-Sensitive Antibiotics Are Not Inactivated During Polymethylmethacrylate Curing and Can Be Used in Cement Spacers for Periprosthetic Joint Infection.

PubMed

Carli, Alberto V; Sethuraman, Arvinth S; Bhimani, Samrath J; Ross, Frederick P; Bostrom, Mathias P G

2018-06-01

Antibiotic use in polymethylmethacrylate (PMMA) spacers has historically been limited to those which are "heat-stable" and thus retain their antimicrobial properties after exposure to the high temperatures which occur during PMMA curing. This study examines the requirement of "heat stability" by measuring temperatures of Palacos and Simplex PMMA as they cure inside commercial silicone molds of the distal femur and proximal tibia. Temperature probes attached to thermocouples were placed at various depths inside the molds and temperatures were recorded for 20 minutes after PMMA introduced and a temperature curve for each PMMA product was determined. A "heat-stable" antibiotic, vancomycin, and a "heat-sensitive" antibiotic, ceftazidime, were placed in a programmable thermocycler and exposed to the same profile of PMMA curing temperatures. Antimicrobial activity against Staphylococcus aureus was compared for heat-treated antibiotics vs room temperature controls. Peak PMMA temperatures were significantly higher in tibial (115.2°C) vs femoral (85.1°C; P < .001) spacers. In the hottest spacers, temperatures exceeded 100°C for 3 minutes. Simplex PMMA produced significantly higher temperatures (P < .05) compared with Palacos. Vancomycin bioactivity did not change against S aureus with heat exposure. Ceftazidime bioactivity did not change when exposed to femoral temperature profiles and was reduced only 2-fold with tibial profiles. The curing temperatures of PMMA in knee spacers are not high enough or maintained long enough to significantly affect the antimicrobial efficacy of ceftazidime, a known "heat-sensitive" antibiotic. Future studies should investigate if more "heat-sensitive" antibiotics could be used clinically in PMMA spacers. Copyright © 2018 Elsevier Inc. All rights reserved.

Antibiotic-Resistant Bacteria: There is Hope.

ERIC Educational Resources Information Center

Offner, Susan

1998-01-01

Argues that reduction in the use of antibiotics would enable antibiotic-sensitive bacteria to flourish. Presents an activity designed to show students how a small, seemingly unimportant difference in doubling time can, over a period of time, make an enormous difference in population size. (DDR)

Childhood urinary tract infection in primary care: a prospective observational study of prevalence, diagnosis, treatment, and recovery.

PubMed

Butler, Christopher C; O'Brien, Kathryn; Pickles, Timothy; Hood, Kerenza; Wootton, Mandy; Howe, Robin; Waldron, Cherry-Ann; Thomas-Jones, Emma; Hollingworth, William; Little, Paul; Van Der Voort, Judith; Dudley, Jan; Rumsby, Kate; Downing, Harriet; Harman, Kim; Hay, Alastair D

2015-04-01

The prevalence of targeted and serendipitous treatment for, and associated recovery from, urinary tract infection (UTI) in pre-school children is unknown. To determine the frequency and suspicion of UTI in children who are acutely ill, along with details of antibiotic prescribing, its appropriateness, and whether that appropriateness impacted on symptom improvement and recovery. Prospective observational cohort study in primary care sites in urban and rural areas in England and Wales. Systematic urine sampling from children aged <5 years presenting in primary care with acute illness with culture in NHS laboratories. Of 6079 children's urine samples, 339 (5.6%) met laboratory criteria for UTI and 162 (47.9%) were prescribed antibiotics at the initial consultation. In total, 576/7101 (8.1%) children were suspected of having a UTI prior to urine sampling, including 107 of the 338 with a UTI (clinician sensitivity 31.7%). Children with a laboratory-diagnosed UTI were more likely to be prescribed antibiotics when UTI was clinically suspected than when it was not (86.0% versus 30.3%, P<0.001). Of 231 children with unsuspected UTI, 70 (30.3%) received serendipitous antibiotics (that is, antibiotics prescribed for a different reason). Overall, 176 (52.1%) children with confirmed UTI did not receive any initial antibiotic. Organism sensitivity to the prescribed antibiotic was higher when UTI was suspected than when treated serendipitously (77.1% versus 26.0%; P<0.001). Children with UTI prescribed appropriate antibiotics at the initial consultation improved a little sooner than those with a UTI who were not prescribed appropriate antibiotics initially (3.5 days versus 4.0 days; P = 0.005). Over half of children with UTI on culture were not prescribed antibiotics at first presentation. Serendipitous UTI treatment was relatively common, but often inappropriate to the organism's sensitivity. Methods for improved targeting of antibiotic treatment in children who are acutely unwell are urgently needed. © British Journal of General Practice 2015.

Childhood urinary tract infection in primary care: a prospective observational study of prevalence, diagnosis, treatment, and recovery

PubMed Central

Butler, Christopher C; O’Brien, Kathryn; Pickles, Timothy; Hood, Kerenza; Wootton, Mandy; Howe, Robin; Waldron, Cherry-Ann; Thomas-Jones, Emma; Hollingworth, William; Little, Paul; Van Der Voort, Judith; Dudley, Jan; Rumsby, Kate; Downing, Harriet; Harman, Kim; Hay, Alastair D

2015-01-01

Background The prevalence of targeted and serendipitous treatment for, and associated recovery from, urinary tract infection (UTI) in pre-school children is unknown. Aim To determine the frequency and suspicion of UTI in children who are acutely ill, along with details of antibiotic prescribing, its appropriateness, and whether that appropriateness impacted on symptom improvement and recovery. Design and setting Prospective observational cohort study in primary care sites in urban and rural areas in England and Wales. Method Systematic urine sampling from children aged <5years presenting in primary care with acute illness with culture in NHS laboratories. Results Of 6079 children’s urine samples, 339 (5.6%) met laboratory criteria for UTI and 162 (47.9%) were prescribed antibiotics at the initial consultation. In total, 576/7101 (8.1%) children were suspected of having a UTI prior to urine sampling, including 107 of the 338 with a UTI (clinician sensitivity 31.7%). Children with a laboratory-diagnosed UTI were more likely to be prescribed antibiotics when UTI was clinically suspected than when it was not (86.0% versus 30.3%, P<0.001). Of 231 children with unsuspected UTI, 70 (30.3%) received serendipitous antibiotics (that is, antibiotics prescribed for a different reason). Overall, 176 (52.1%) children with confirmed UTI did not receive any initial antibiotic. Organism sensitivity to the prescribed antibiotic was higher when UTI was suspected than when treated serendipitously (77.1% versus 26.0%; P<0.001). Children with UTI prescribed appropriate antibiotics at the initial consultation improved a little sooner than those with a UTI who were not prescribed appropriate antibiotics initially (3.5 days versus 4.0 days; P = 0.005). Conclusion Over half of children with UTI on culture were not prescribed antibiotics at first presentation. Serendipitous UTI treatment was relatively common, but often inappropriate to the organism’s sensitivity. Methods for improved targeting of antibiotic treatment in children who are acutely unwell are urgently needed. PMID:25824181

Emerging Trends of Bloodstream Infections: A Six-Year Study at a Paediatric Tertiary Care Hospital in Kabul.

PubMed

Tariq, Tariq Mahmud; Rasool, Esmatullah

2016-11-01

To determine the frequency of pathogens causing bloodstream infections and evaluate their trends and antibiogram patterns among in-patients in a paediatric tertiary care centre. Descriptive study. French Medical Institute for Mothers and Children (FMIC), Kabul, Afghanistan in two phases, from January 2010 to December 2015. Results of blood cultures from suspected cases of sepsis admitted in the FMIC, from January 2010 to December 2012 (Period-1), and from January 2013 to December 2015 (Period-2) were completed. Standard microbiological methods were followed for blood culture and antibiotic sensitivity testing. Out of total 1,040 cases of culture proven sepsis, 528 (50.77%) Gram-negative bacilli (GNB), 474 (45.58%) Gram-positive cocci (GPC), and 38 (3.65%) Candida species were isolated during the entire study period. Out of 528 GNB isolates, 373 (70.64%) belonged to the Enterobacteriaceae and 155 (29.36%) were non-fermenters. Among Enterobacteriaceae, 168 (31.82%) were Klebsiella species (K. pneumoniae=124, K. oxytoca=44), 70 (13.26%) were Enterobacter species (E. cloacae=52, E. aerogenes=18), 65 (12.31%) were E. coli, 37 (7.01%) were Serratia marcescens and 31 (5.87%) were others. Out of 155 non-fermenters, 88 (16.67%) were Pseudomonas aeruginosa, 39 (7.39%) were Burkholderia cepacia and 18 (3.41%) were Stenotrophomonas maltophilia. There was a drop in the frequency of Enterobacteriaceae from 85% in Period-1 to 58.68% in Period-2. There was an increase in the frequency of nonfermenters from 15% to 41.32%, particularly 18 new cases of sepsis caused by Stenotrophomonas maltophilia during Period-2. Among GPC, there was an overall rise of 16.14% in the prevalence of Staphylococcus epidermidis during Period-2 and a drop of 9.64% in the frequency of Staphylococcus aureus during Period-2. The majority of Gram-negative isolates were multidrug-resistant to commonly used antibiotics. However, most of the isolates were sensitive to amikacin and imipenem (except S. maltophilia). The frequency of those producing ESBL reduced by 11.22% during the Period-2. Among Gram-positive cocci, the pattern of antibiogram did not show a significant change during both periods, and majority remained resistant to commonly used antibiotics. All Staphylococci were sensitive to vancomycin but resistant to penicillin. There was a substantial decline of 18.87% in the frequency of Methicillin-resistant Staphylococci (MRSA/MRSE) during Period-2. Staphylococci and Klebsiellae remain the most important bacteria responsible for bloodstream infections in a tertiary healthcare facility in Kabul. Yet, there has been an increase in the prevalence of Pseudomonas and Burkholderia cepacia. Moreover, Stenotrophomonas maltophilia emerged as a new hospital acquired pathogen. This study could possibly help in suggesting choices eluding the misuse of appropriate antibiotics.

A comparison of inpatient versus outpatient resistance patterns of pediatric urinary tract infection.

PubMed

Saperston, Kara N; Shapiro, Daniel J; Hersh, Adam L; Copp, Hillary L

2014-05-01

Prior single center studies showed that antibiotic resistance patterns differ between outpatients and inpatients. We compared antibiotic resistance patterns for urinary tract infection between outpatients and inpatients on a national level. We examined outpatient and inpatient urinary isolates from children younger than 18 years using The Surveillance Network (Eurofins Scientific, Luxembourg, Luxembourg), a database of antibiotic susceptibility results, as well as patient demographic data from 195 American hospitals. We determined the prevalence and antibiotic resistance patterns of the 6 most common uropathogens, including Escherichia coli, Proteus mirabilis, Klebsiella, Enterobacter, Pseudomonas aeruginosa and Enterococcus. We compared differences in uropathogen prevalence and resistance patterns for outpatient and inpatient isolates using chi-square analysis. We identified 25,418 outpatient (86% female) and 5,560 inpatient (63% female) urinary isolates. Escherichia coli was the most common uropathogen overall but its prevalence varied by gender and visit setting, that is 79% of uropathogens overall for outpatient isolates, including 83% of females and 50% of males, compared to 54% for overall inpatient isolates, including 64% of females and 37% of males (p <0.001). Uropathogen resistance to many antibiotics was lower in the outpatient vs inpatient setting, including trimethoprim/sulfamethoxazole 24% vs 30% and cephalothin 16% vs 22% for E. coli (each p <0.001), cephalothin 7% vs 14% for Klebsiella (p = 0.03), ceftriaxone 12% vs 24% and ceftazidime 15% vs 33% for Enterobacter (each p <0.001), and ampicillin 3% vs 13% and ciprofloxacin 5% vs 12% for Enterococcus (each p <0.001). Uropathogen resistance rates of several antibiotics are higher for urinary specimens obtained from inpatients vs outpatients. Separate outpatient vs inpatient based antibiograms can aid in empirical prescribing for pediatric urinary tract infections. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

[Comparison of the sensitivity of pathogenic staphylococci isolated in 1974 to certain antibiotics and nitrofuran derivatives].

PubMed

Val'vachev, N I; Vilenchik, G I; Rimzha, M I

1976-03-01

Sensitivity of 267 strains of pathogenic staphylococci isolated in 1974 was studied with respect to some antibiotics and nitrofuran derivatives by the method of serial dilutions on solid media. Sensitivity to penicillin, oxacillin, olemorphocycline, ristomycin and nitrofuran derivatives (furagin and salafur) was observed in 30.7 +/- 2.8, 61.8 +/-3, 29.2 +/-2.8 and 98.9 +/- 0.8 per cent of the cultures respectively.

Rapid and sensitive screening and selective quantification of antibiotics in human urine by two-dimensional ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

PubMed

Wang, He-Xing; Wang, Bin; Zhou, Ying; Jiang, Qing-Wu

2014-12-01

A rapid and sensitive method for the screening and selective quantification of antibiotics in urine by two-dimensional ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was developed. This method allowed the injection of 200 μL urine extract. The 200-μL injection volume used in this method increased the absolute sensitivity for target antibiotics in solvent by an average 13.3 times, with a range from 8.4 to 28.5 times, compared with the 10-μL conventional injection volume. A 96-well solid phase extraction procedure was established to eliminate the contamination on the chromatographic column resulting from the large-volume injection and increase the throughput of sample preparation. Fourteen target antibiotics from six common categories (β-lactams, quinolones, tetracyclines, macrolides, sulfonamides, and chloramphenicols) were selected as model compounds, and a database containing an additional 74 antibiotics was compiled for posttarget screening. The limit of detection of the target antibiotics, defined as a signal-to-noise ratio of 3, ranged from 0.04 to 1.99 ng/mL. The mean interday recoveries ranged between 79.6 and 121.3 %, with a relative standard deviation from 2.9 to 18.3 % at three spiking levels of 20 ng/mL, 50 ng/mL, and 100 ng/mL. This method was successfully applied in 60 real urine samples from schoolchildren aged 8-11 years, and four target antibiotics (azithromycin, sulfadiazine, trimethoprim, and oxytetracycline) and two posttarget antibiotics (sulfadimidine and cefaclor) were found in the urine samples. This method can be used as a large-scale biomonitoring tool for exposure of the human population to antibiotics.

Neonatal mastitis: a clinico-microbiological study.

PubMed

Masoodi, Talat; Mufti, Gowhar Nazir; Bhat, Javeed Iqbal; Lone, Rubina; Arshi, Syed; Ahmad, Syed Khurshid

2014-01-01

Neonatal breast hypertrophy is a common phenomenon in term infants, superadded infection can lead to mastitis and that can progress to breast abscess with short and long term detrimental effects. Our effort is to study the prevalence, risk factors, the current microbial profile and sensitivity pattern in these infections in order to suggest an optimal treatment plan for these patients. Case series. Hospital based study conducted in Kashmir on the native population. 2011 to 2013. 32 neonates with features of mastitis or abscess were included in the study. Demographic and clinical data, laboratory work-up were recorded for all these patients in a patient form. Gram stain of the purulent nipple discharge or pus obtained on drainage was done and the specimens were culture plated. Antibiotic sensitivity was determined by disk diffusion and categorized by current Clinical and Laboratory Standards Institute (CLSI) guidelines. Most babies were full term, the age range was 6-48 days. Peak incidence for mastitis was in the 2nd week and for abscess in the 4th week. The ratio of male: female was 1:2 in the entire group, there was greater preponderance of female involvement with increasing age. Massage for expression of secretions a common practice in the study population had been done in 15 patients, especially in male babies. The babies were generally well and associated skin pustulosis was common. Laboratory workup showed polymorphonuclear leucocytosis and CRP positivity. Gram staining showed gram positive cocci in 13 patients and gram negative rods in 1 patient. Culture revealed Staphylococcus aureus in 18, E.col in 2, klebsiella in 1 patient and was sterile in 2 patients. Most strains of Staphylococcus aureus were resistant to macrolides and penicillins. Fifteen were methicillin sensitive and 3 were resistant but were sensitive to amikacin, ofloxacin and vancomycin. Gram negative rods were sensitive to, aminoglycosides, chloramphenicol, quinolones, piperacillin-tazobactum and cefoperazone-sulbactum, but were resistant to cephalosporins including third generation cephalosporins. Treatment with oral antibiotic was not successful. Patients responded well to open drainage via a stab incision away from the breast mound; 4 patients were managed by repeated needle aspirations. IV antibiotics were prescribed in all patients for 2-5 days, followed by oral continuation therapy of 7-14 days. From our study, we can conclude that parental counseling to avoid massage, and early treatment for pustulosis is important to prevent mastitis. Intravenous antibiotics should be used for this condition guided by gram stain or culture sensitivity once available. Empirically a drug with good anti-staph cover may be instituted till appropriate reports are available. Incision drainage gives uniformly good results, though; multiple sittings of needle drainage may obviate the need for incision drainage. Therapy can be shifted to oral drugs once clinical improvement is seen.

Surveillance of antibiotic use in the private sector in Namibia using sales and claims data.

PubMed

Pereko, Dawn Dineo; Lubbe, Martie S; Essack, Sabiha Y

2016-11-24

Antibiotics are among the most commonly used therapeutic agents for humans globally, and their use has been associated with the development of resistance. The objective of this study was to identify sources for quantifying antibiotic usage patterns and to assess such use in ambulatory patients in the private health sector of Namibia. A retrospective analysis of prescription claims data and sales data for the period 2008 to 2011 was conducted. Antibiotic use was expressed in the number of antibiotic-containing prescriptions and volume of units sold and then standardized using defined daily dose per 1,000 inhabitants per day. Antibiotic usage was highest in females (53%), in people 18-45 years of age (41%), and in Windhoek (34%). Overall, wholesale data showed higher antibiotic use than prescription claims data. However, both sources showed similar patterns of antibiotic use. Penicillins were the most used pharmacological group, with amoxicillin/clavulanic acid combination being the most used of the agents. Antibiotic use in the private sector of Namibia is comparable to that of high-consuming European countries such as Italy. A trend observed in this study was the decrease in the use of narrow-spectrum antibiotics in favour of broad-spectrum and newer antibiotics. Since this was the first study to assess antibiotic use in the private sector of Namibia, it could serve as a starting point for continued monitoring of antibiotic use in the whole of Namibia in the context of the World Health Organization's Global Action Plan to contain antibiotic resistance.

Fluorescent Metal-Organic Framework (MOF) as a Highly Sensitive and Quickly Responsive Chemical Sensor for the Detection of Antibiotics in Simulated Wastewater.

PubMed

Zhu, Xian-Dong; Zhang, Kun; Wang, Yu; Long, Wei-Wei; Sa, Rong-Jian; Liu, Tian-Fu; Lü, Jian

2018-02-05

A Zn(II)-based fluorescent metal-organic framework (MOF) was synthesized and applied as a highly sensitive and quickly responsive chemical sensor for antibiotic detection in simulated wastewater. The fluorescent chemical sensor, denoted FCS-1, exhibited enhanced fluorescence derived from its highly ordered, 3D MOF structure as well as excellent water stability in the practical pH range of simulated antibiotic wastewater (pH = 3.0-9.0). Remarkably, FCS-1 was able to effectively detect a series of sulfonamide antibiotics via photoinduced electron transfer that caused detectable fluorescence quenching, with fairly low detection limits. Two influences impacting measurements related to wastewater treatment and water quality monitoring, the presence of heavy-metal ions and the pH of solutions, were studied in terms of fluorescence quenching, which was nearly unaffected in sulfonamide-antibiotic detection. Additionally, the effective detection of sulfonamide antibiotics was rationalized by the theoretical computation of the energy bands of sulfonamide antibiotics, which revealed a good match between the energy bands of FCS-1 and sulfonamide antibiotics, in connection with fluorescence quenching in this system.

Phenotypic and antibiogram pattern of V. cholerae isolates from a tertiary care hospital in Mumbai during 2004–2013: a retrospective cross-sectional study

PubMed Central

Torane, V; Kuyare, S; Nataraj, G; Mehta, P; Dutta, S; Sarkar, B

2016-01-01

Objectives Cholera is a major gastroenteric disease with reports on fluctuation and resistance. Hence, the objective is to determine the trend in seasonality, resistance pattern, prevalent biotypes, serotypes and phage types between 2004 and 2013 among Vibrio cholerae isolates. Design A retrospective cross-sectional study. Settings A single-centre study was carried out at a tertiary care hospital in a metropolitan city (Mumbai) of a developing country (India). Methods Records of stool specimen cultures of patients with suspected cholera from January 2004 to December 2013 were analysed. The organisms were identified as per standard protocol. Antimicrobial susceptibility testing was performed as per Clinical Laboratory Standard Institute. Biotyping, serotyping and phage typing were carried out. From the confirmed cases of cholera, demographic and laboratory details were noted. Descriptive analysis was used and the data were presented in the form of percentages. Results Vibrio cholerae was predominant in males and was isolated from 9.41% (439/4664) of stool specimens. Variability was found in terms of the gross appearance of stool specimens, seasonal trend and antibiotic resistance pattern. The antimicrobial susceptibility showed a waxing and waning pattern for most of the antibiotics (ampicillin, cefuroxime, chloramphenicol, tetracycline) tested, while for a few others the strains were either uniformly sensitive (gentamicin, norfloxacin) or resistant (trimethoprim-sulfamethoxazole, nalidixic acid). All isolates belonged to subgroup O1 and biotype El Tor. The most common serotype was Ogawa. The predominant phage type was T2 (old scheme) and T27 (new scheme). Conclusions The predominant biotype, serotype and phage type were El Tor, Ogawa and T27 phage, respectively. The changing trends in antimicrobial resistance pattern over the years necessitate continued epidemiological and microbiological surveillance of the disease. PMID:27888174

Methicillin-resistant Staphylococcus aureus (MRSA) in a tertiary surgical and trauma hospital in Benghazi, Libya.

PubMed

Buzaid, Najat; Elzouki, Abdel-Naser; Taher, Ibrahim; Ghenghesh, Khalifa Sifaw

2011-10-13

Methicillin resistant Staphylococcus aureus (MRSA) is a multidrug resistant organism that threatens the continued effectiveness of antibiotics worldwide and causes a threat almost exclusively in hospitals and long-term care settings. This study investigated the prevalence of MRSA strains and their sensitivity patterns against various antibiotics used for treating hospitalized patients in a major tertiary surgical hospital in Benghazi, Libya. We investigated 200 non-duplicate S. aureus strains isolated from different clinical specimens submitted to the Microbiology Laboratory at Aljala Surgical and Trauma Hospital, Benghazi, Libya from April to July 2007. Isolates were tested for methicillin resistance by the oxacillin disc-diffusion assay according to Clinical and Laboratory Standards Institute guidelines. MRSA strains were tested for antimicrobial resistance (i.e., vancomycin, ciprofloxacin, erythromycin, chloramphenicol and fusidic acid) using commercial discs. Information on patient demographics and clinical disease was also collected. Of the isolates examined 31% (62/200) were MRSA. No significant differences were observed in the prevalence of MRSA among S. aureus from females or males or from different age groups. Most MRSA were isolated from burns and surgical wound infections. Antibiotic resistance patterns of 62 patients with MRSA to vancomycin, ciprofloxacin, fusidic acid, chloramphenicol and erythromycin were 17.7%, 33.9%, 41.9%, 38.7% and 46.8% of cases, respectively. MRSA prevalence in our hospital was high and this may be the case for other hospitals in Libya. A sound surveillance program of nosocomial infections is urgently needed to reduce the incidence of infections due to MRSA and other antimicrobial-resistant pathogens in Libyan hospitals.

Ecological consequences of antibiotic exposure to periphyton in naturally colonizing stream mesocosms

EPA Science Inventory

Tetracycline and its derivatives are extensively used human and animal antibiotics, and enter stream ecosystems via point and non-point sources. Laboratory studies indicate that microbial organisms are more sensitive to antibiotics than invertebrates or fish, and may indicate t...

Sensitizing pathogens to antibiotics using the CRISPR-Cas system.

PubMed

Goren, Moran; Yosef, Ido; Qimron, Udi

2017-01-01

The extensive use of antibiotics over the last century has resulted in a significant artificial selection pressure for antibiotic-resistant pathogens to evolve. Various strategies to fight these pathogens have been introduced including new antibiotics, naturally-derived enzymes/peptides that specifically target pathogens and bacteriophages that lyse these pathogens. A new tool has recently been introduced in the fight against drug-resistant pathogens-the prokaryotic defense mechanism-clustered regularly interspaced short palindromic repeats-CRISPR associated (CRISPR-Cas) system. The CRISPR-Cas system acts as a nuclease that can be guided to cleave any target DNA, allowing sophisticated, yet feasible, manipulations of pathogens. Here, we review pioneering studies that use the CRISPR-Cas system to specifically edit bacterial populations, eliminate their resistance genes and combine these two strategies in order to produce an artificial selection pressure for antibiotic-sensitive pathogens. We suggest that intelligent design of this system, along with efficient delivery tools into pathogens, may significantly reduce the threat of antibiotic-resistant pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

Streamlining antibiotic therapy with procalcitonin protocols: consensus and controversies.

PubMed

Haubitz, Sebastian; Mueller, Beat; Schuetz, Philipp

2013-04-01

Accumulating evidence supports procalcitonin (PCT) as an accurate surrogate biomarker for likelihood and severity of bacterial infections. In community-acquired pneumonia and other respiratory infections, PCT-guided antibiotic therapy algorithms resulted in reduced antibiotic exposure while maintaining a similar or even better level of safety compared with standard care. Reductions in antibiotic use translate into lower treatment costs, decreased risk of side effects and decreased bacterial multiresistance. This is especially important, as acute respiratory infections represent the most frequent reason for antibiotic prescriptions worldwide. Still, there is some controversy about the benefits of PCT measurement in sepsis patients in the intensive care unit and for nonrespiratory infections. Highly sensitive PCT assays are readily available in many hospitals today, and point-of-care assays with high enough sensitivity for antibiotic guidance are expected to be available soon. Herein, the authors provide an overview of recent studies evaluating PCT in different clinical situations and an outlook of currently enrolling or upcoming interventional trials.

Measuring Coverage in MNCH: A Prospective Validation Study in Pakistan and Bangladesh on Measuring Correct Treatment of Childhood Pneumonia

PubMed Central

el Arifeen, Shams; Khan, Amira M.; Huque, M. Hamidul; Kazmi, Narjis; Roy, Sushmita; Abbasi, Saleem; Rahman, Qazi Sadeq-ur; Theodoratou, Evropi; Khorshed, Mahmuda Shayema; Rahman, Kazi Mizanur; Bari, Sanwarul; Kaiser, M. Mahfuzul Islam; Saha, Samir K.; Ahmed, A. S. M. Nawshad Uddin; Rudan, Igor; Bryce, Jennifer; Qazi, Shamim Ahmad; Campbell, Harry

2013-01-01

Background Antibiotic treatment for pneumonia as measured by Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS) is a key indicator for tracking progress in achieving Millennium Development Goal 4. Concerns about the validity of this indicator led us to perform an evaluation in urban and rural settings in Pakistan and Bangladesh. Methods and Findings Caregivers of 950 children under 5 y with pneumonia and 980 with “no pneumonia” were identified in urban and rural settings and allocated for DHS/MICS questions 2 or 4 wk later. Study physicians assigned a diagnosis of pneumonia as reference standard; the predictive ability of DHS/MICS questions and additional measurement tools to identify pneumonia versus non-pneumonia cases was evaluated. Results at both sites showed suboptimal discriminative power, with no difference between 2- or 4-wk recall. Individual patterns of sensitivity and specificity varied substantially across study sites (sensitivity 66.9% and 45.5%, and specificity 68.8% and 69.5%, for DHS in Pakistan and Bangladesh, respectively). Prescribed antibiotics for pneumonia were correctly recalled by about two-thirds of caregivers using DHS questions, increasing to 72% and 82% in Pakistan and Bangladesh, respectively, using a drug chart and detailed enquiry. Conclusions Monitoring antibiotic treatment of pneumonia is essential for national and global programs. Current (DHS/MICS questions) and proposed new (video and pneumonia score) methods of identifying pneumonia based on maternal recall discriminate poorly between pneumonia and children with cough. Furthermore, these methods have a low yield to identify children who have true pneumonia. Reported antibiotic treatment rates among these children are therefore not a valid proxy indicator of pneumonia treatment rates. These results have important implications for program monitoring and suggest that data in its current format from DHS/MICS surveys should not be used for the purpose of monitoring antibiotic treatment rates in children with pneumonia at the present time. Please see later in the article for the Editors' Summary PMID:23667339

Antibiotic Resistance Patterns of Major Zoonotic Pathogens from All-Natural, Antibiotic-Free, Pasture-Raised Broiler Flocks in the Southeastern United States.

PubMed

Rothrock, Michael J; Hiett, Kelli L; Guard, Jean Y; Jackson, Charlene R

2016-03-01

The use of antibiotics in agroecosystems has been implicated in the rise in antibiotic resistance (AR), which can affect environmental, animal, and human health. To determine the environmental impact of antibiotic use in agroecosystems, appropriate background levels of AR in agricultural environments in the absence of antibiotic application must be determined. Therefore, to determine background levels of AR in broiler production, four target microbes (, , , and ) were isolated from 15 all-natural, antibiotic-free, pasture-raised broiler flocks from six farms within the southeastern United States. The AR profiles of these isolates were characterized using the CDC National Antimicrobial Resistance Monitoring System for Enteric Bacteria (NARMS), and these resistance patterns were compared across target microbes and farms and throughout the life cycle of the flocks along the farm-to-fork continuum. Antibiotic resistances were most prevalent in and and least prevalent in . Although and were isolated from the same farms and characterized using the same NARMS plates, they exhibited distinct AR profiles, with demonstrating clear farm-specific resistance patterns. Multidrug resistance rates (three or more antibiotics), in order of prevalence, were (63.9%), (36.0%), (12.7%), and (1.4%). The results of this study demonstrate the variability in background AR among major food safety-related microbes, even when isolated from similar production and processing samples from the same farms, and indicate the need for the proper design of future broiler production studies to account for this highly dynamic background AR. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Management Trends in Prenatally-Detected Hydronephrosis: A National Survey of Pediatrician Practice Patterns and Antibiotic Use

PubMed Central

Yiee, Jenny H.; Tasian, Gregory E.; Copp, Hillary L.

2011-01-01

Objectives Hydronephrosis is the most common abnormality found on prenatal ultrasound. The utility of prophylactic antibiotics in the postnatal management of this condition is controversial. No study has assessed practice patterns of general pediatricians in the management of prenatally-detected hydronephrosis. Methods An 18 question survey was sent to a random cross-sectional national sample of pediatricians from the American Medical Association Masterfile. Participants answered questions regarding practice location and type, practice experience, frequency of cases seen, familiarity with the literature, use of antibiotics, work-up of hydronephrosis, and specialist referral. Multivariate logistic regression identified factors associated with prescribing antibiotics. Results 244 of 461 (53%) subjects responded. 56% routinely prescribe antibiotics for prenatally-detected hydronephrosis. 57% perform postnatal work-up themselves. Of these, 98% routinely order ultrasounds while ~40% routinely order voiding cystourethrograms. 94% have specialists readily available, but only 41% always refer to a specialist. On multivariate logistic regression, those who believe prophylactic antibiotics to be beneficial are significantly more likely to prescribe antibiotics compared with those who have not read the literature (OR 6.1, 95%CI 2–15). Those without specialist consultation readily available have an increased odds of starting prophylactic antibiotics compared with those who have consultation available (OR 7.2, 95%CI 1.3–39). Conclusion Most pediatricians initiate postnatal management of prenatally-detected hydronephrosis, therefore pediatricians truly are gatekeepers to children with this condition. Knowledge of practice patterns is crucial for the dissemination of evidence-based information to the appropriate providers and enables us to learn more about the utility of antibiotic prophylaxis in future studies. PMID:21696811

Survival of Listeria monocytogenes with different antibiotic resistance patterns to food-associated stresses.

PubMed

Komora, Norton; Bruschi, Carolina; Magalhães, Rui; Ferreira, Vânia; Teixeira, Paula

2017-03-20

The ongoing rise of antibiotic resistant microbial pathogens has become one of the major public health threats worldwide. Despite all the effort and actions taken so far, a proliferation of antibiotic resistant (AR) and multi-antibiotic resistant (MAR) strains is still observed, including in foodborne pathogens. This trend has been also noted recently for isolates of Listeria monocytogenes, a species that, although remaining largely sensitive to clinically relevant antimicrobials, has been reported to develop increased tolerance to antibiotics, particularly in isolates recovered from the food-chain. In this study we compared the ability of MAR (n=8), AR (n=18) and antibiotic susceptible (AS, n=11) L. monocytogenes strains from food and clinical origin to survive to different environmental stress conditions, including temperature (58°C), acidic stress (1% v/v lactic acid, pH3.5), and osmotic stress (37% w/v NaCl). The presence of antibiotic active efflux among MAR and AR strains, and its role on L. monocytogenes tolerance to different antimicrobial compounds was also investigated, namely; hydrogen peroxide; organic acids (acetic, citric and lactic); nisin; benzalkonium chloride (BC); and, sodium nitrite. While no significant differences were observed in the survival of the 37 strains exposed to high temperature (58°C), overall the mean logarithmic reduction of clinical strains was statistically lower after acid and salt exposure than that observed for strains of food origin; but both food and clinical strains resistant to two or three antibiotics were significantly less susceptible to acid (lactic acid 1% v/v) and osmotic stresses (37% w/v NaCl) when compared to AS strains. Using the EtBr-agar Cartwheel method, it was possible to detect efflux pumps in three of the 26 MAR and AR isolates, including one control strain; the active efflux in theses isolates was proven to be associated with fluoroquinolone resistance, and possible extrusion of BC and hydrogen peroxide. The mechanisms responsible for the possible correlation between resistance to antibiotics and to acid or salt stress in L. monocytogenes have yet to be understood. Copyright © 2017 Elsevier B.V. All rights reserved.

Patterns of c-reactive protein RATIO response in severe community-acquired pneumonia: a cohort study.

PubMed

Coelho, Luís M; Salluh, Jorge I F; Soares, Márcio; Bozza, Fernando A; Verdeal, Juan Carlos R; Castro-Faria-Neto, Hugo C; Lapa e Silva, José Roberto; Bozza, Patrícia T; Póvoa, Pedro

2012-12-12

Community-acquired pneumonia (CAP) requiring intensive care unit (ICU) admission remains a severe medical condition, presenting ICU mortality rates reaching 30%. The aim of this study was to assess the value of different patterns of C-reactive protein (CRP)-ratio response to antibiotic therapy in patients with severe CAP requiring ICU admission as an early maker of outcome. In total, 191 patients with severe CAP were prospectively included and CRP was sampled every other day from D1 to D7 of antibiotic prescription. CRP-ratio was calculated in relation to D1 CRP concentration. Patients were classified according to an individual pattern of CRP-ratio response with the following criteria: fast response - when D5 CRP was less than or equal to 0.4 of D1 CRP concentration; slow response - when D5 CRP was > 0.4 and D7 less than or equal to 0.8 of D1 CRP concentration; nonresponse - when D7 CRP was > 0.8 of D1 CRP concentration. Comparison between ICU survivors and non-survivors was performed. CRP-ratio from D1 to D7 decreased faster in survivors than in non-survivors (p = 0.01). The ability of CRP-ratio by D5 to predict ICU outcome assessed by the area under the ROC curve was 0.73 (95% Confidence Interval, 0.64 - 0.82). By D5, a CRP concentration above 0.5 of the initial level was a marker of poor outcome (sensitivity 0.81, specificity 0.58, positive likelihood ratio 1.93, negative likelihood ratio 0.33). The time-dependent analysis of CRP-ratio of the three patterns (fast response n = 66; slow response n = 81; nonresponse n = 44) was significantly different between groups (p < 0.001). The ICU mortality rate was considerably different according to the patterns of CRP-ratio response: fast response 4.8%, slow response 17.3% and nonresponse 36.4% (p < 0.001). In severe CAP, sequential evaluation of CRP-ratio was useful in the early identification of patients with poor outcome. The evaluation of CRP-ratio pattern of response to antibiotics during the first week of therapy was useful in the recognition of the individual clinical evolution.

[Characteristics of drug resistance and molecular typing research for Salmonella Enteritidis isolated in Henan province from 2011 to 2013].

PubMed

Zhao, Jiayong; Zhang, Yukai; Xie, Zhiqiang; Pan, Jingjing; Su, Jia; Mu, Yujiao; Huang, Xueyong; Zhang, Baifan; Xia, Shengli

2016-03-01

To investigate the antimicrobial resistance status and pulsed field gel electrophoresis (PFGE) patterns of Salmonella Enteritidis (S.Enteritidis) strains in Henan province. S. Enteritidis strains were isolated from seven sentinel hospitals from March 2011 to December 2013. According to molecular typing and Salmonella (Kirby-Bauer, K-B) drug susceptibility testing method published by the international PulseNet bacterial infectious disease monitoring network and USA Clinical and Laboratory Standards Institute (CLSI), we analyzed drug sensitivity of 8 kinds antibiotics and PFGE molecule characteristics of 120 S. Enteritidis isolates from seven sentinel hospitals. Among 120 strains of S. Enteritidis, 77 were isolated from male patients, 43 from female patients. A total of 78 strains S. Enteritidis were isolated from young children ranged from 0 to 5 years old (65.0%), including 57 strains isolated from 6 months to 2 years old (47.5%). The isolated time mainly centralized on May to October of the year, 11 strains isolated in March-April (9.2%), 48 were in May-July (40.0%),54 in August-October (45.0%), 7 in other months, with a typical summer seasonal characteristics. The resistance rate of 120 strains S. Enteritidis to ampicillin was 50.0% (n=60); to ceftazidime was 14.2% (n=17), to cefotaxime was 18.3% (n=22); to cefepime was 5.8% (n=7); to nalidixic acid was 61.7% (n=74); to ciprofloxacin was 8.3% (n=10), to norfloxacin was 5.8% (n=7); to gentamicin was 42.5% (n=51); to streptomycin was 21.7% (n=26); to chloramphenicol was 30.0% (n=36); resistance to methicillin benzyl ammonium was 11.7% (n=14), compound sulfamethoxazole resistance rate was 71.7% (n=86); the tetracycline resistant rate was 47.5% (n=57). All 120 strains of S. Enteritidis had different levels of resistance to 8 kinds of antibiotics, all strains were multidrug resistant strains, 28 isolates were resistant to 3-4 kinds of antibiotics (23.3%), 38 isolates were resistant to 5-6 kinds of antibiotics (31.7%), 39 isolates were resistant to 7-8 kinds of antibiotics (32.5%). All 120 strains of S. Enteritidis were divided into 44 molecular patterns by digestion with XbaI and pulsed field gel electrophoresis. each pattern contained 1-35 strains with similarity ranged from 54.3%-100%. EN14 and EN19 were the main PFGE types, including 35 and 29 strains respectively. The status of drug resistance of clinical isolates of Salmonella in Henan province was rather serious, PFGE patterns showed advantages and partial strain's corresponding resistant spectrum have certain relevance and the same aggregation relationship.

An Observational Study of Antibiotic Prescribing Behavior and the Hawthorne Effect

PubMed Central

Mangione-Smith, Rita; Elliott, Marc N; McDonald, Laurie; McGlynn, Elizabeth A

2002-01-01

Objectives To assess whether prospective, observational study procedures, including questionnaires and audio recording, are associated with different patterns of physician diagnostic decision making and antibiotic prescribing. Data Sources/Setting (1) Survey data from a prospective observational study of treatment patterns for children with acute upper respiratory illnesses (10/96–3/97) and (2) retrospective medical record abstraction data of nonobserved encounters for the same problems occurring during (10/96–3/97) and one year after (10/97–3/98) the observational study period. Ten pediatricians in two community practices were studied. Study Design Patterns of diagnoses recorded in the medical record and antibiotics ordered for visits occurring outside of the observational study (same time period and one year later) were compared with the pattern of diagnoses and antibiotics ordered during the observational study. Data Collection/Extraction Methods For the observational study (10/96–2/97), diagnosis and treatment choices were obtained from questionnaires completed by physicians immediately following the visit. For the nonstudy encounters (10/96–3/97 and 10/97–3/98), data were abstracted from medical records one year after the observational study was completed. Principal Findings The proportion of viral cases in which an antibiotic was prescribed was 29 percentage points lower for the observational study compared to the retrospective analysis (p <.05). In one of two study sites, the proportion of cases assigned a bacterial diagnosis was 29 percentage points lower in the observational study period compared to the retrospective study (p <.05). Conclusions Observational study procedures including questionnaires and audio recording can affect antibiotic prescribing behavior. Future observational studies aimed at examining the frequency of inappropriate antibiotic prescribing should measure and adjust for the Hawthorne effect; without such adjustments, the results will likely underestimate the true degree of the problem. Future interventions aimed at decreasing inappropriate antibiotic prescribing should consider “harnessing” the Hawthorne effect through performance feedback to participating physicians. PMID:12546288

Regional variation in antibiotic prescribing among medicare part D enrollees, 2013.

PubMed

Arizpe, Andre; Reveles, Kelly R; Aitken, Samuel L

2016-12-09

Antibiotics are among the most widely prescribed medications. The geographic variation in antibiotic prescribing patterns and associated costs among Medicare Part D recipients have not been described. The purpose of this study was to assess the regional variation in antibiotic prescriptions and costs among Medicare Part D enrollees in 2013. Retrospective cohort review of all Medicare Part D enrollees in 2013, using the Medicare Provider Utilization and Payment Data: Part D Prescriber Public Use File. All original or refill prescription claims for antibiotics as listed in the Part D Prescriber Public Use File were included. Our primary outcomes were total antibiotic claims and antibiotic cost per Medicare Part D Enrollee. Data were analyzed descriptively by state and by geographic region as defined by the United States Census Bureau. Antibiotic claims were described overall and by antibiotic class. Over 54 million outpatient antibiotic claims were filed for Part D enrollees in 2013, representing more than $1.5 billion in total antibiotic expenditures. Antibiotic use was highest in the South (1,623 claims/1,000 enrollees), followed by the Midwest (1,401 claims/1,000 enrollees), Northeast (1,366 claims/1,000 enrollees), and West (1,292 claims/1,000 enrollees). Average antibiotic costs per enrollee in each region were as follows: South $46.58, Northeast $43.70, Midwest $40.54, and West $36.42. Fluoroquinolones were the most commonly prescribed class overall (12.2 million claims). Antibiotic use among elderly Medicare enrollees in the United States was highest in the South region. Fluoroquinolones were the most common antibiotics used in all regions. These patterns could be utilized in the development of targeted antimicrobial stewardship efforts.

ANTIBIOTIC RESISTANCE SPECTRUM OF NON FERMENTING GRAM NEGATIVE BACILLI ISOLATED IN THE ORTHOPEDIC TRAUMATOLOGY CLINIC OF "SF. SPIRIDON" CLINICAL EMERGENCY HOSPITAL IAŞI.

PubMed

Tucaliuc, D; Alexa, O; Tuchiluş, Cristina Gabriela; Ursu, Ramona Gabriela; Tucaliuc, Elena Simona; Jelihovsky, I; Iancu, Luminiţa Smaranda

2015-01-01

The retro-prospective analysis of antibiotic sensitivity of non-fermenting gram negative bacilli strains circulating in the Orthopedics-Traumatology Clinic from "Sf. Spiridon" Emergency Clinical Hospital in view of determining the trend of the resistance phenomenon and indicating the most useful treatment for the infections caused by these strains. The retrospective component was conducted from 01.01.2003 to 31.12.2012, and the result of the diffusimetric antibiograms was taken from the hospital's informatics system; the prospective component of the study involved the collection of pathological products from the patients admitted during January-December 2013, who showed clinical suspicion of infection, in compliance with the general collection norms for the products destined for the bacteriological exam. From the total 167 strains of Pseudomonas aeruginosa isolated and identified from the patients, 48 (28.74%) were sensitive to at least one antibiotic from each tested class, 29 (17.39%) were resistant to a single antibiotic and the rest of 90 (53.89%) showed multiple resistance. We noticed a statistically significant difference between the number of strains sensitive to at least one antibiotic from each tested class and those with multiple resistance (p < 0.05). For the strains of Acinetobacter baumanii combined resistance was identified for 121 (87.04%), out of which 55 (39.56%) were resistant to two classes of antibiotics and the other (47.48%) to all three classes. The most frequently met was the association of resistance to quinolones and aminoglycosides, namely for a number of 49 strains (35.25%); only 3.59% of them were simultaneously sensitive to the three classes of antibiotics. The already high percentages and the rising trends of antibiotic resistance of non-fermenting gram-negative bacteria described in this study confirm the continuous decrease of the efficiency of antimicrobial agents and underline the necessity of a global strategy which aims at all health sectors regarding the rational use of antibiotics, on the one hand, and the continuation of studies concerning the surveillance of the antimicrobial resistance phenomenon, on the other hand.

[Comparison of the antibiotic sensitivity of lipophilic Corynebacterium sp. isolated from patients on the day of admission and during hospitalization].

PubMed

Ciok-Pater, Emilia; Mikucka, Agnieszka; Gospodarek, Eugenia

2005-01-01

Lipophilic species of Corynebacterium are increasing problem in hospital infections. The aim of this study was to evaluate occurrence of these microorganisms in the materials taken from patients in the day of admission and during the hospitalization as well as comparison of their antibiotic sensitivity. The investigation included 65 strains isolated from hospitalized patients and 48 strains isolated from unchanged skin. Using Api Coryne test 5 species were identified. C. urealyticum dominated, the other were C. subsp. lipophilum and C. jeikeium. Among strains isolated from unchanged diseased skin the most C. jeikeium and C. accolens occurred. All strains were sensitive to glycopeptide, quinupristin/dalphopristin. The strains isolated from hospitalized patients were usually sensitive to fuside acid, doxycycline as well as tetracycline. Strains isolated from unchanged skin were sensitive to almost all tested antibiotics. In the group of 65 strains isolated from hospitalized patients 99.0% were multiresistant. In the group of strains isolated from unchanged skin only two strains were multiresistant. Differences in antibiotic sensitivity among analysed Corynebacterium sp. were confirmed. Majority of the "hospital strains" were characterized by multiresistance. Basing on these results it is possible to suppose, that multiresistance is main factor that favours lipophilic Corynebacterium species in the process of colonization of mucous membranes, skins as well as developing infections.

Persistence of antibiotic-resistant and -sensitive Proteus mirabilis strains in the digestive tract of the housefly (Musca domestica) and green bottle flies (Calliphoridae).

PubMed

Wei, Ting; Miyanaga, Kazuhiko; Tanji, Yasunori

2014-10-01

Synanthropic flies have been implicated in the rapid dissemination of antibiotic-resistant bacteria and resistance determinants in the biosphere. These flies stably harbor a considerable number of bacteria that exhibit resistance to various antibiotics, but the mechanisms underlying this phenomenon remain unclear. In this study, we investigated the persistence of antibiotic-resistant bacteria in the digestive tract of houseflies and green bottle flies, using Proteus mirabilis as a model microorganism. One resistant strain carried the blaTEM and aphA1 genes, and another carried a plasmid containing qnrD gene. Quantitative PCR and 454 pyrosequencing were used to monitor the relative abundance of the Proteus strains, as well as potential changes in the overall structure of the whole bacterial community incurred by the artificial induction of Proteus cultures. Both antibiotic-resistant and -sensitive P. mirabilis strains persisted in the fly digestive tract for at least 3 days, and there was no significant difference in the relative abundance of resistant and sensitive strains despite the lower growth rate of resistant strains when cultured in vitro. Therefore, conditions in the fly digestive tract may allow resistant strains to survive the competition with sensitive strains in the absence of antibiotic selective pressure. The composition of the fly-associated bacterial community changed over time, but the contribution of the artificially introduced P. mirabilis strains to these changes was not clear. In order to explain these changes, it will be necessary to obtain more information about bacterial interspecies antagonism in the fly digestive tract.

Molecular and Proteomic Analysis of Levofloxacin and Metronidazole Resistant Helicobacter pylori.

PubMed

Hanafi, Aimi; Lee, Woon Ching; Loke, Mun Fai; Teh, Xinsheng; Shaari, Ain; Dinarvand, Mojdeh; Lehours, Philippe; Mégraud, Francis; Leow, Alex Hwong Ruey; Vadivelu, Jamuna; Goh, Khean Lee

2016-01-01

Antibiotic resistance in bacteria incurs fitness cost, but compensatory mechanisms may ameliorate the cost and sustain the resistance even under antibiotics-free conditions. The aim of this study was to determine compensatory mechanisms of antibiotic resistance in H. pylori . Five strains of levofloxacin-sensitive H. pylori were induced in vitro to develop resistance. In addition, four pairs of metronidazole-sensitive and -resistant H. pylori strains were isolated from patients carrying dual H. pylori populations that consist of both sensitive and resistant phenotypes. Growth rate, virulence and biofilm-forming ability of the sensitive and resistant strains were compared to determine effects of compensatory response. Proteome profiles of paired sensitive and resistant strains were analyzed by liquid chromatography/mass spectrophotometry (LC/MS). Although there were no significant differences in growth rate between sensitive and resistant pairs, bacterial virulence (in terms of abilities to induce apoptosis and form biofilm) differs from pair to pair. These findings demonstrate the complex and strain-specific phenotypic changes in compensation for antibiotics resistance. Compensation for in vitro induced levofloxacin resistance involving mutations of gyrA and gyrB was functionally random. Furthermore, higher protein translation and non-functional protein degradation capabilities in naturally-occuring dual population metronidazole sensitive-resistant strains may be a possible alternative mechanism underlying resistance to metronidazole without mutations in rdxA and frxA . This may explain the lack of mutations in target genes in ~10% of metronidazole resistant strains.

Molecular and Proteomic Analysis of Levofloxacin and Metronidazole Resistant Helicobacter pylori

PubMed Central

Hanafi, Aimi; Lee, Woon Ching; Loke, Mun Fai; Teh, Xinsheng; Shaari, Ain; Dinarvand, Mojdeh; Lehours, Philippe; Mégraud, Francis; Leow, Alex Hwong Ruey; Vadivelu, Jamuna; Goh, Khean Lee

2016-01-01

Antibiotic resistance in bacteria incurs fitness cost, but compensatory mechanisms may ameliorate the cost and sustain the resistance even under antibiotics-free conditions. The aim of this study was to determine compensatory mechanisms of antibiotic resistance in H. pylori. Five strains of levofloxacin-sensitive H. pylori were induced in vitro to develop resistance. In addition, four pairs of metronidazole-sensitive and -resistant H. pylori strains were isolated from patients carrying dual H. pylori populations that consist of both sensitive and resistant phenotypes. Growth rate, virulence and biofilm-forming ability of the sensitive and resistant strains were compared to determine effects of compensatory response. Proteome profiles of paired sensitive and resistant strains were analyzed by liquid chromatography/mass spectrophotometry (LC/MS). Although there were no significant differences in growth rate between sensitive and resistant pairs, bacterial virulence (in terms of abilities to induce apoptosis and form biofilm) differs from pair to pair. These findings demonstrate the complex and strain-specific phenotypic changes in compensation for antibiotics resistance. Compensation for in vitro induced levofloxacin resistance involving mutations of gyrA and gyrB was functionally random. Furthermore, higher protein translation and non-functional protein degradation capabilities in naturally-occuring dual population metronidazole sensitive-resistant strains may be a possible alternative mechanism underlying resistance to metronidazole without mutations in rdxA and frxA. This may explain the lack of mutations in target genes in ~10% of metronidazole resistant strains. PMID:28018334

Reserve Drug Indent Form and Its Impact on Antimicrobial Consumption and Sensitivity Pattern in the Medical Intensive Care Unit of a Tertiary Care Hospital

PubMed Central

Anitha, K.B.; Rai, Mohandas; Fernandes, Anisha

2015-01-01

Objectives: A world without effective antibiotics is a terrifying but a real prospect. Overuse or misuse especially of newer and higher antimicrobials (AM) is of particular concern, as this contributes to development of resistance among microorganisms. To check this trend, the Reserve Drug Indent Form (RDIF) was introduced in our hospital and its impact on AM consumption, cost of therapy and the sensitivity pattern was studied in the medical intensive care unit (MICU). Materials and Methods: A retrospective descriptive study in the medical ICU of a tertiary care hospital from July 2012 to August 2013. From March 2013, RDIF was made mandatory to be filled up prior to prescribing reserve antimicrobials. AM consumption (expressed as DDD/100 bed days) and sensitivity pattern (expressed in percentage) six months prior to and six months after implementation of the form were analysed. Results: The total Reserve AM consumption was 125.79 per 100 bed days during the study period. Average occupancy index was 0.50 and length of ICU stay was 6 days. The total consumption reduced from 85.55/100 to 40.24/100 bed days after the introduction of the RDIF. However, Imipenem usage increased from 11.35/100 to 23.94/100 bed days, which can be attributed to sensitivity profile to Imipenem (82.1%) compared to Meropenem (65.7%). Cost of therapy reduced from Rs 6,27,951 to 4,20,469. Conclusion: Reserve AM consumption showed a declining trend after introduction of the RDIF. Hence, the RDIF served as an important tool to combat inappropriate use, reducing the cost burden and also helped to improve the sensitivity to reserve drugs. PMID:25859466

Antibiotics resistance in El Tor Vibrio cholerae 01 isolated during cholera outbreaks in Mozambique from 2012 to 2015

PubMed Central

2017-01-01

Rationale Mozambique has recorded cyclically epidemic outbreaks of cholera. Antibiotic therapy is recommended in specific situations for management and control of cholera outbreaks. However, an increase in resistance rates to antibiotics by Vibrio cholerae has been reported in several epidemic outbreaks worldwide. On the other hand, there are few recent records of continuous surveillance of antibiotics susceptibility pattern of V. cholerae in Mozambique. Goals The purpose of this study was to evaluate antibiotics resistance pattern of Vibrio cholerae O1 Ogawa isolated during Cholera outbreaks in Mozambique to commonly used antibiotics. Methodology We analyzed data from samples received in the context of surveillance and response to Cholera outbreaks in the National Reference Laboratory of Microbiology from the National Institute of Health of Mozambique, 159 samples suspected of cholera from cholera treatment centers of, Metangula (09), Memba (01), Tete City (08), Moatize (01), Morrumbala (01) districts, City of Quelimane (01), Lichinga (06) and Nampula (86) districts, from 2012 to 2015. Laboratory culture and standard biochemical tests were employed to isolate and identify Vibrio cholerae; serotypes were determined by antisera agglutination reaction in blade. Biotype and presence of important virulence factors analysis was done by PCR. Antibiotics susceptibility pattern was detected by disk diffusion method Kirby Bauer. Antibiotic susceptibility and results were interpreted by following as per recommendations of CLSI (Clinical and Laboratory Standards Institute) 2014. All samples were collected and tested in the context of Africhol Project, approved by the National Bioethics Committee for Health. Results Among isolates from of Vibrio cholerae O1 El Tor Ogawa resistance to Sulphamethoxazole-trimethropim was 100% (53/53) to Trimethoprim-, being 100% (54/54) for Ampicillin, 99% (72/74) for Nalidixic Acid, 97% (64/66) to Chloramphenicol, 95% (42/44) for Nitrofurantoin and (19/20) Cotrimoxazole, 83% (80/97) Tetracycline, 56% (5/13) Doxycycline, 56% (39/70) Azithromycin and 0% (0/101) for Ciprofloxacin. PCR analysis suggested strains of V. cholerae O1 being descendants of the current seventh pandemic V. cholerae O1 CIRS 101 hybrid variant. The V. cholerae O1 currently causing cholera epidemics in north and central Mozambique confirmed a CTXΦ genotype and a molecular arrangement similar to the V. cholerae O1 CIRS 101. Conclusion Although V. cholerae infections in Mozambique are generally not treated with antibiotics circulating strains of the bacteria showed high frequency of in vitro resistance to available antibiotics. Continuous monitoring of antibiotic resistance pattern of epidemic strains is therefore crucial since the appearance of antibiotic resistance can influence cholera control strategies. PMID:28792540

Antibiotics resistance in El Tor Vibrio cholerae 01 isolated during cholera outbreaks in Mozambique from 2012 to 2015.

PubMed

Dengo-Baloi, Liliana Candida; Semá-Baltazar, Cynthia Amino; Manhique, Lena Vania; Chitio, Jucunu Elias; Inguane, Dorteia Luísa; Langa, José Paulo

2017-01-01

Mozambique has recorded cyclically epidemic outbreaks of cholera. Antibiotic therapy is recommended in specific situations for management and control of cholera outbreaks. However, an increase in resistance rates to antibiotics by Vibrio cholerae has been reported in several epidemic outbreaks worldwide. On the other hand, there are few recent records of continuous surveillance of antibiotics susceptibility pattern of V. cholerae in Mozambique. The purpose of this study was to evaluate antibiotics resistance pattern of Vibrio cholerae O1 Ogawa isolated during Cholera outbreaks in Mozambique to commonly used antibiotics. We analyzed data from samples received in the context of surveillance and response to Cholera outbreaks in the National Reference Laboratory of Microbiology from the National Institute of Health of Mozambique, 159 samples suspected of cholera from cholera treatment centers of, Metangula (09), Memba (01), Tete City (08), Moatize (01), Morrumbala (01) districts, City of Quelimane (01), Lichinga (06) and Nampula (86) districts, from 2012 to 2015. Laboratory culture and standard biochemical tests were employed to isolate and identify Vibrio cholerae; serotypes were determined by antisera agglutination reaction in blade. Biotype and presence of important virulence factors analysis was done by PCR. Antibiotics susceptibility pattern was detected by disk diffusion method Kirby Bauer. Antibiotic susceptibility and results were interpreted by following as per recommendations of CLSI (Clinical and Laboratory Standards Institute) 2014. All samples were collected and tested in the context of Africhol Project, approved by the National Bioethics Committee for Health. Among isolates from of Vibrio cholerae O1 El Tor Ogawa resistance to Sulphamethoxazole-trimethropim was 100% (53/53) to Trimethoprim-, being 100% (54/54) for Ampicillin, 99% (72/74) for Nalidixic Acid, 97% (64/66) to Chloramphenicol, 95% (42/44) for Nitrofurantoin and (19/20) Cotrimoxazole, 83% (80/97) Tetracycline, 56% (5/13) Doxycycline, 56% (39/70) Azithromycin and 0% (0/101) for Ciprofloxacin. PCR analysis suggested strains of V. cholerae O1 being descendants of the current seventh pandemic V. cholerae O1 CIRS 101 hybrid variant. The V. cholerae O1 currently causing cholera epidemics in north and central Mozambique confirmed a CTXΦ genotype and a molecular arrangement similar to the V. cholerae O1 CIRS 101. Although V. cholerae infections in Mozambique are generally not treated with antibiotics circulating strains of the bacteria showed high frequency of in vitro resistance to available antibiotics. Continuous monitoring of antibiotic resistance pattern of epidemic strains is therefore crucial since the appearance of antibiotic resistance can influence cholera control strategies.

Isolation and identification of methylobacterium species from the tap water in hospitals in Japan and their antibiotic susceptibility.

PubMed

Furuhata, Katsunori; Kato, Yuko; Goto, Keiichi; Hara, Motonobu; Yoshida, Shin-ichi; Fukuyama, Masafumi

2006-01-01

Contamination of tap water by Methylobacterium species has become a serious concern in hospitals. This study was planned to examine the distribution of Methylobacterium species inhabiting tap water used in Japanese hospitals and antibiotic sensitivity of the isolates in 2004. Species identification of 58 isolates was performed based on the homology of a partial sequence of 16S rDNA. The dominant Methylobacterium species in hospital water were M. aquaticum and M. fujisawaense. To examine the biochemical properties of these isolates, a carbon source utilization was tested using an API50CH kit. The phenotypic character varied widely, and was not necessarily consistent with the results of phylogenic analysis based on the partial 16S rDNA sequence, suggesting that the biochemical properties are not suitable for identification of Methylobacterium species. The isolates were also subjected to antibiotic sensitivity tests. They were resistant to 8 antibiotics, but highly sensitive to imipenem (MIC90 = 1 microg/ml) and tetracycline (MIC90 = 8 microg/ml). These findings concerning the isolates revealed the presence of Methylobacterium species with resistance to multiple antibiotics in hospital tap water.

Guideline recommendations and antimicrobial resistance: the need for a change.

PubMed

Elias, Christelle; Moja, Lorenzo; Mertz, Dominik; Loeb, Mark; Forte, Gilles; Magrini, Nicola

2017-07-26

Antimicrobial resistance has become a global burden for which inappropriate antimicrobial use is an important contributing factor. Any decisions on the selection of antibiotics use should consider their effects on antimicrobial resistance. The objective of this study was to assess the extent to which antibiotic prescribing guidelines have considered resistance patterns when making recommendations for five highly prevalent infectious syndromes. We used Medline searches complemented with extensive use of Web engine to identify guidelines on empirical treatment of community-acquired pneumonia, urinary tract infections, acute otitis media, rhinosinusitis and pharyngitis. We collected data on microbiology and resistance patterns and identified discrete pattern categories. We assessed the extent to which recommendations considered resistance, in addition to efficacy and safety, when recommending antibiotics. We identified 135 guidelines, which reported a total of 251 recommendations. Most (103/135, 79%) were from developed countries. Community-acquired pneumonia was the syndrome mostly represented (51, 39%). In only 16 (6.4%) recommendations, selection of empirical antibiotic was discussed in relation to resistance and specific microbiological data. In a further 69 (27.5%) recommendations, references were made in relation to resistance, but the attempt was inconsistent. Across syndromes, 12 patterns of resistance with implications on recommendations were observed. 50% to 75% of recommendations did not attempt to set recommendation in the context of these patterns. There is consistent evidence that guidelines on empirical antibiotic use did not routinely consider resistance in their recommendations. Decision-makers should analyse and report the extent of local resistance patterns to allow better decision-making. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The Pattern of Antibiotic Prescribing by Dental Practitioners in Zagreb, Croatia.

PubMed

Perić, Marina; Perković, Ivana; Romić, Martina; Simeon, Paris; Matijević, Jurica; Mehičić, Goranka Prpić; Krmek, Silvana Jukić

2015-06-01

Bacterial resistance is considered a consequence of misuse or overuse of antibiotics. Dentistry significantly contributes to this increasing public health problem. The aim of this cross-sectional study was to examine the pattern of antibiotics prescribed by Croatian dentists in Zagreb area. Out of 220 Doctors of Dental Medicine (DMDs) from Zagreb 110 responded to survey. Prior to the research an ethical approval was obtained. Participants were directly contacted. The questionnaire consisted of two parts: general data on DMDs and the part concerning indications, duration, type and dosage of antibiotic therapy. Data were processed using MS Excel and SPSS for Windows, Version 17.0. Statistical significance was tested by Fisher's exact test, chi-square test, Mann-Whitney U test and Spearman's rank correlation at the level of statistical significance p<0.05. During the period of two months, the doctors prescribed antibiotics to 1,500 patients, 690 (46%) were men and 810 (54%) women. The most often prescribed antibiotics were penicillin (72.5% of patients), represented mostly by amoxicillin in combination with clavulanic acid (57.6%). The most common indication for the prescribed antibiotics was periapical or periodontal abscess (44%). Definite clinical indication (71.2%) was stated as the most common reason for antibiotic prescription. Antibiotic therapy usually lasted 7 days (62.9%). The doctors prescribed daily doses of antibiotics according to the instructions for the use of specific drugs. The examined subjects prescribe antibiotics according to the curriculum taught at the School of Dental Medicine for majority of types, doses and duration of the treatments, although antibiotics over-prescription in cases without medical indication was observed. The national guidelines on antibiotic regimens are required in order to reduce unnecessary antibiotic use. Copyright© by the National Institute of Public Health, Prague 2015.

Patterns of use and appropriateness of antibiotics prescribed to patients receiving haemodialysis: an observational study.

PubMed

Hui, Katrina; Nalder, Michelle; Buising, Kirsty; Pefanis, Aspasia; Ooi, Khai Y; Pedagogos, Eugenie; Nelson, Craig; Kirkpatrick, Carl M J; Kong, David C M

2017-05-12

There are limited published data on the types and appropriateness of oral and intravenous (IV) antibiotics prescribed to patients receiving haemodialysis. This information is critical to optimise antibiotic prescribing. Therefore this study aims to describe the patterns of use and the appropriateness of oral and IV antibiotics prescribed to patients receiving haemodialysis. This was a prospective, observational study across four community and two hospital inpatient haemodialysis units in Melbourne, Australia. Data were collected from July 2014 to January 2015 from participants. Antibiotic regimens prescribed were compared with nationally available antibiotic guidelines and then classified as being either appropriate, inappropriate or not assessable by an expert multidisciplinary team using the National Antimicrobial Prescribing Survey tool. Overall, 114 participants consented to this study where 55.3% (63/114) received antibiotics and 235 antibiotic regimens were prescribed at a rate of 69.1 antibiotic regimens/100 patient-months. The most common oral antibiotics prescribed were amoxycillin/clavulanic acid and cephalexin. The most common IV antibiotics prescribed were vancomycin, piperacillin/tazobactam, cephazolin and ceftriaxone. The percentage of inappropriate antibiotic regimens prescribed were 34.9% (15/43) in the community setting and 22.1% (40/181) in the hospital setting. Furthermore, 29.4% (30/102) of oral and 20.5% (25/122) of IV antibiotic regimens were inappropriate with incorrect dosing as the primary reason. Although this study is limited by the sample size, it describes the high antibiotic exposure that patients receiving haemodialysis experience. Of concern is inappropriate dose and frequency being a major issue. This requires interventions focused on the quality use of medicines and antimicrobial stewardship aspects of prescribing in this population.

Clinical and Diagnostic Aspects of Brucellosis and Antimicrobial Susceptibility of Brucella Isolates in Hamedan, Iran.

PubMed

Torkaman Asadi, Fatemeh; Hashemi, Seyyed Hamid; Alikhani, Mohammad Yousef; Moghimbeigi, Abbas; Naseri, Zahra

2017-05-24

Current drug regimens for brucellosis are associated with relatively high rates of therapeutic failure or relapse. Reduced antimicrobial susceptibility of Brucella spp. has been proposed recently as a potential cause of therapeutic failure. The aim of this study was to evaluate the antibiotic resistance pattern of Brucella melitensis clinical isolates by E-test method in Hamadan, west of Iran. In a 15-month period, all patients with suspected brucellosis were enrolled. Blood specimens were collected for diagnosis of brucellosis by BACTEC system and serological tests. Antimicrobial susceptibility of clinical isolates to 7 antibiotics was assessed by the E-test method. One hundred forty-nine patients with brucellosis were evaluated. 38.3% of cultures of clinical samples were positive for BACTEC system, of which 91.2% were associated with a positive serological test result. No significant associations were found between serology and the culture method. All Brucella isolates were susceptible to doxycycline, streptomycin, gentamicin, ciprofloxacin, and moxifloxacin. However, decreased sensitivity to rifampin and trimethoprim-sulfamethoxazole was found in 35.1% and 3.5% of isolates, respectively. Because of the high rates of intermediate sensitivity to rifampin among Brucella isolates, this drug should be prescribed with caution. We recommend restricting the use of rifampin for treatment of brucellosis except as an alternative drug for special situations.

Development and Validation of a UPLC-MS/MS Method to Monitor Cephapirin Excretion in Dairy Cows following Intramammary Infusion

PubMed Central

Ray, Partha; Knowlton, Katharine F.; Shang, Chao; Xia, Kang

2014-01-01

Cephapirin, a cephalosporin antibiotic, is used by the majority of dairy farms in the US. Fecal and urinary excretion of cephapirin could introduce this compound into the environment when manure is land applied as fertilizer, and may cause development of bacterial resistance to antibiotics critical for human health. The environmental loading of cephapirin by the livestock industry remains un-assessed, largely due to a lack of appropriate analytical methods. Therefore, this study aimed to develop and validate a cephapirin quantification method to capture the temporal pattern of cephapirin excretion in dairy cows following intramammary infusion. The method includes an extraction with phosphate buffer and methanol, solid-phase extraction (SPE) clean-up, and quantification using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The LOQ values of the developed method were 4.02 µg kg−1 and 0.96 µg L−1 for feces and urine, respectively. This robust method recovered >60% and >80% cephapirin from spiked blank fecal and urine samples, respectively, with acceptable intra- and inter-day variation (<10%). Using this method, we detected trace amounts (µg kg−1) of cephapirin in dairy cow feces, and cephapirin in urine was detected at very high concentrations (133 to 480 µg L−1). Cephapirin was primarily excreted via urine and its urinary excretion was influenced by day (P = 0.03). Peak excretion (2.69 mg) was on day 1 following intramammary infusion and decreased sharply thereafter (0.19, 0.19, 0.08, and 0.17 mg on day 2, 3, 4, and 5, respectively) reflecting a quadratic pattern of excretion (Quadratic: P = 0.03). The described method for quantification of cephapirin in bovine feces and urine is sensitive, accurate, and robust and allowed to monitor the pattern of cephapirin excretion in dairy cows. This data will help develop manure segregation and treatment methods to minimize the risk of antibiotic loading to the environment from dairy farms. PMID:25375097

What about Urinary Tract Infections and its Antibiotic Resistance Bacteria in Ilam, Iran?

PubMed

Mohebi, Reza; Esmaili, Khadijeh; Sadeghifard, Nourkhoda; Pakzad, Iraj; Ghafourian, Sobhan

2018-06-22

Because of unknown situation of antibiotic resistance pattern in main hospital in Ilam, Iran, in an attempt we aimed to evaluate the antibiotic resistance pattern of uropathogenic bacteria obtained from referred patients to Imam Khomaini Hospital, Ilam, Iran. For this reason, 114 bacteria were collected during 9 month period and evaluated for their antibiotic resistance pattern. Our results demonstrated that E. coli as the dominant responsible for urinary tract infection. Our results demonstrated that 61.4 % (n = 70) of isolates were positive for E.coli, while the lowest prevalence observed for Staphylococcus aureus and Acinetobacter baumannii. The results demonstrated that 6.4% (n = 7) were MBL producer. Despite, only 4 gram positive bacteria were obtained from patients with urinary tract infections but 100% (n = 1) of S. aureus were methicillin resistant S. aureus (MRSA) and 66.7% (n = 2) of E. faecalis were positive for resistance to vancomycin. In conclusion, we strongly recommended doing the cohort study among all hospital in Iran to evaluate the situation of antibiotic resistance and make a real panel to control this issue. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Zero-magnetic field effect in pathogen bacteria

NASA Astrophysics Data System (ADS)

Creanga, D. E.; Poiata, A.; Morariu, V. V.; Tupu, P.

2004-05-01

Two lots of Gram-negative bacterial strains were tested for antibiotic drug resistance after exposure to zero-magnetic field. We found that the magneto-sensitive strains represent half of the analyzed samples (three Pseudomonas and five Enterobacter strains), some of them presenting two-three times modified resistance to antibiotic, while others revealed eight or 16 times changed resistance. Pseudomonas strain magnetic sensitivity is revealed better by ampicillin and tetracycline, while Enterobacter strain magnetic sensitivity is revealed better by ampicillin, kanamycin and ofloxacin.

In-vitro activity of flomoxef, a new oxacephem group antibiotic, against Nocardia in comparison with other cephalosporins.

PubMed

Yazawa, K; Mikami, Y; Uno, J; Otozai, K; Arai, T

1989-12-01

The susceptibility of 113 strains of pathogenic Nocardia, N. asteroides, N. farcinica, N. nova, N. brasiliensis and N. otitidiscaviarum to a new oxacephem antibiotic flomoxef was determined by an agar dilution method in comparison with those of 13 other cephalosporins. Flomoxef was two to 50 times more active against these pathogenic Nocardia than other cephalopsorins tested. However, there were differences in susceptibility to this antibiotic among these Nocardia strains. N. asteroides was the most sensitive species, followed by N. farcinica and N. nova. N. brasiliensis was moderately sensitive and N. otitidiscaviarum was resistant.

Removal of total and antibiotic resistant bacteria in advanced wastewater treatment by ozonation in combination with different filtering techniques.

PubMed

Lüddeke, Frauke; Heß, Stefanie; Gallert, Claudia; Winter, Josef; Güde, Hans; Löffler, Herbert

2015-02-01

Elimination of bacteria by ozonation in combination with charcoal or slow sand filtration for advanced sewage treatment to improve the quality of treated sewage and to reduce the potential risk for human health of receiving surface waters was investigated in pilot scale at the sewage treatment plant Eriskirch, Baden-Wuerttemberg/Germany. To determine the elimination of sewage bacteria, inflowing and leaving wastewater of different treatment processes was analysed in a culture-based approach for its content of Escherichia coli, enterococci and staphylococci and their resistance against selected antibiotics over a period of 17 month. For enterococci, single species and their antibiotic resistances were identified. In comparison to the established flocculation filtration at Eriskirch, ozonation plus charcoal or sand filtration (pilot-scale) reduced the concentrations of total and antibiotic resistant E. coli, enterococci and staphylococci. However, antibiotic resistant E. coli and staphylococci apparently survived ozone treatment better than antibiotic sensitive strains. Neither vancomycin resistant enterococci nor methicillin resistant Staphylococcus aureus (MRSA) were detected. The decreased percentage of antibiotic resistant enterococci after ozonation may be explained by a different ozone sensitivity of species: Enterococcus faecium and Enterococcus faecalis, which determined the resistance-level, seemed to be more sensitive for ozone than other Enterococcus-species. Overall, ozonation followed by charcoal or sand filtration led to 0.8-1.1 log-units less total and antibiotic resistant E. coli, enterococci and staphylococci, as compared to the respective concentrations in treated sewage by only flocculation filtration. Thus, advanced wastewater treatment by ozonation plus charcoal or sand filtration after common sewage treatment is an effective tool for further elimination of microorganisms from sewage before discharge in surface waters. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of point-of-care C-reactive protein testing on antibiotic prescription habits in primary care in the Netherlands.

PubMed

Schuijt, Tim J; Boss, David S; Musson, Ruben E A; Demir, Ayse Y

2018-03-27

Bacterial resistance to antibiotics represents a serious global challenge that is associated with high morbidity and mortality. One of the most important causes of this threat is antibiotic overuse. The Dutch College of General Practitioners (DCGP) recommends the use of point-of-care (POC) testing for C-reactive protein (CRP) in two guidelines ('Acute Cough' and 'Diverticulitis') to achieve a more sensible prescription pattern of antibiotics. To evaluate the use of POC-CRP testing in light of the DCGP guidelines and the effect of CRP measurements on antibiotic prescription policy in primary care. In a prospective observational study, which included 1756 patients, general practitioners (GPs) were asked to complete a questionnaire after every POC-CRP testing, stating the indication for performing the test, the CRP result and their decision whether or not to prescribe antibiotics. Indications were verified against the DCGP guidelines and categorized. Antibiotic prescription was evaluated in relation to CRP concentrations. Indications to perform POC-CRP test and the prescription pattern of antibiotics based on CRP value varied considerably between GPs. Differences in antibiotic prescription rate were most obvious in patients who presented with CRP values between 20 and 100 mg/l, and could in part be explained by the indication for performing POC-CRP test and patient age. Most GPs followed the DCGP guidelines and used low CRP values to underpin their decision to refrain from antibiotic prescription. Peer-based reflection on differences in POC-CRP usage and antibiotic prescription rate amongst GPs may further nourish a more critical approach to prescription of antibiotics.

In Silico Analysis of Antibiotic Resistance Genes in the Gut Microflora of Individuals from Diverse Geographies and Age-Groups

PubMed Central

Ghosh, Tarini Shankar; Gupta, Sourav Sen; Nair, Gopinath Balakrish; Mande, Sharmila S.

2013-01-01

The spread of antibiotic resistance, originating from the rampant and unrestrictive use of antibiotics in humans and livestock over the past few decades has emerged as a global health problem. This problem has been further compounded by recent reports implicating the gut microbial communities to act as reservoirs of antibiotic resistance. We have profiled the presence of probable antibiotic resistance genes in the gut flora of 275 individuals from eight different nationalities. For this purpose, available metagenomic data sets corresponding to 275 gut microbiomes were analyzed. Sequence similarity searches of the genomic fragments constituting each of these metagenomes were performed against genes conferring resistance to around 240 antibiotics. Potential antibiotic resistance genes conferring resistance against 53 different antibiotics were detected in the human gut microflora analysed in this study. In addition to several geography/country-specific patterns, four distinct clusters of gut microbiomes, referred to as ‘Resistotypes’, exhibiting similarities in their antibiotic resistance profiles, were identified. Groups of antibiotics having similarities in their resistance patterns within each of these clusters were also detected. Apart from this, mobile multi-drug resistance gene operons were detected in certain gut microbiomes. The study highlighted an alarmingly high abundance of antibiotic resistance genes in two infant gut microbiomes. The results obtained in the present study presents a holistic ‘big picture’ on the spectra of antibiotic resistance within our gut microbiota across different geographies. Such insights may help in implementation of new regulations and stringency on the existing ones. PMID:24391833

Global increase and geographic convergence in antibiotic consumption between 2000 and 2015

PubMed Central

Van Boeckel, Thomas P.; Martinez, Elena M.; Pant, Suraj; Gandra, Sumanth; Levin, Simon A.; Goossens, Herman

2018-01-01

Tracking antibiotic consumption patterns over time and across countries could inform policies to optimize antibiotic prescribing and minimize antibiotic resistance, such as setting and enforcing per capita consumption targets or aiding investments in alternatives to antibiotics. In this study, we analyzed the trends and drivers of antibiotic consumption from 2000 to 2015 in 76 countries and projected total global antibiotic consumption through 2030. Between 2000 and 2015, antibiotic consumption, expressed in defined daily doses (DDD), increased 65% (21.1–34.8 billion DDDs), and the antibiotic consumption rate increased 39% (11.3–15.7 DDDs per 1,000 inhabitants per day). The increase was driven by low- and middle-income countries (LMICs), where rising consumption was correlated with gross domestic product per capita (GDPPC) growth (P = 0.004). In high-income countries (HICs), although overall consumption increased modestly, DDDs per 1,000 inhabitants per day fell 4%, and there was no correlation with GDPPC. Of particular concern was the rapid increase in the use of last-resort compounds, both in HICs and LMICs, such as glycylcyclines, oxazolidinones, carbapenems, and polymyxins. Projections of global antibiotic consumption in 2030, assuming no policy changes, were up to 200% higher than the 42 billion DDDs estimated in 2015. Although antibiotic consumption rates in most LMICs remain lower than in HICs despite higher bacterial disease burden, consumption in LMICs is rapidly converging to rates similar to HICs. Reducing global consumption is critical for reducing the threat of antibiotic resistance, but reduction efforts must balance access limitations in LMICs and take account of local and global resistance patterns. PMID:29581252

TRANSFER OF DRUG RESISTANCE BETWEEN ENTERIC BACTERIA INDUCED IN THE MOUSE INTESTINE

PubMed Central

Kasuya, Morimasa

1964-01-01

Kasuya, Morimasa (Nagoya University School of Medicine, Nagoya, Japan). Transfer of drug resistance between enteric bacteria induced in the mouse intestine. J. Bacteriol. 88:322–328. 1964.—Transfer of multiple drug resistance in the intestines of germ-free and conventional mice was studied with strains of Shigella, Escherichia, and Klebsiella. The transfer experiment was carried out under antibiotic-free conditions to eliminate the production of drug-resistant bacteria by antibiotics. All resistance factors (chloramphenicol, streptomycin, tetracycline, and sulfathiazole) were transferred with ease in the intestinal tracts of mice, when donors and recipients multiplied freely, and acquired resistance was further transferred to other sensitive enteric bacteria in the intestinal tract. Bacteria to which resistance factors were transferred showed, in most of the experiments, exactly the same level and pattern of resistance as the donors. Based on the above, a hypothesis that the same process may possibly occur in the human intestine is presented. PMID:14203347

Development of an antibiotic spectrum score based on veterans affairs culture and susceptibility data for the purpose of measuring antibiotic de-escalation: a modified Delphi approach.

PubMed

Madaras-Kelly, Karl; Jones, Makoto; Remington, Richard; Hill, Nicole; Huttner, Benedikt; Samore, Matthew

2014-09-01

Development of a numerical score to measure the microbial spectrum of antibiotic regimens (spectrum score) and method to identify antibiotic de-escalation events based on application of the score. Web-based modified Delphi method. Physician and pharmacist antimicrobial stewards practicing in the United States recruited through infectious diseases-focused listservs. Three Delphi rounds investigated: organisms and antibiotics to include in the spectrum score, operationalization of rules for the score, and de-escalation measurement. A 4-point ordinal scale was used to score antibiotic susceptibility for organism-antibiotic domain pairs. Antibiotic regimen scores, which represented combined activity of antibiotics in a regimen across all organism domains, were used to compare antibiotic spectrum administered early (day 2) and later (day 4) in therapy. Changes in spectrum score were calculated and compared with Delphi participants' judgments on de-escalation with 20 antibiotic regimen vignettes and with non-Delphi steward judgments on de-escalation of 300 pneumonia regimen vignettes. Method sensitivity and specificity to predict expert de-escalation status were calculated. Twenty-four participants completed all Delphi rounds. Expert support for concepts utilized in metric development was identified. For vignettes presented in the Delphi, the sign of change in score correctly classified de-escalation in all vignettes except those involving substitution of oral antibiotics. The sensitivity and specificity of the method to identify de-escalation events as judged by non-Delphi stewards were 86.3% and 96.0%, respectively. Identification of de-escalation events based on an algorithm that measures microbial spectrum of antibiotic regimens generally agreed with steward judgments of de-escalation status.

High-performance thin-layer chromatography screening of multi class antibiotics in animal food by bioluminescent bioautography and electrospray ionization mass spectrometry.

PubMed

Chen, Yisheng; Schwack, Wolfgang

2014-08-22

The world-wide usage and partly abuse of veterinary antibiotics resulted in a pressing need to control residues in animal-derived foods. Large-scale screening for residues of antibiotics is typically performed by microbial agar diffusion tests. This work employing high-performance thin-layer chromatography (HPTLC) combined with bioautography and electrospray ionization mass spectrometry introduces a rapid and efficient method for a multi-class screening of antibiotic residues. The viability of the bioluminescent bacterium Aliivibrio fischeri to the studied antibiotics (16 species of 5 groups) was optimized on amino plates, enabling detection sensitivity down to the strictest maximum residue limits. The HPTLC method was developed not to separate the individual antibiotics, but for cleanup of sample extracts. The studied antibiotics either remained at the start zones (tetracyclines, aminoglycosides, fluoroquinolones, and macrolides) or migrated into the front (amphenicols), while interfering co-extracted matrix compounds were dispersed at hRf 20-80. Only after a few hours, the multi-sample plate image clearly revealed the presence or absence of antibiotic residues. Moreover, molecular information as to the suspected findings was rapidly achieved by HPTLC-mass spectrometry. Showing remarkable sensitivity and matrix-tolerance, the established method was successfully applied to milk and kidney samples. Copyright © 2014 Elsevier B.V. All rights reserved.

Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles.

PubMed

Shen, Li; Chen, Jing; Li, Na; He, Pingli; Li, Zhen

2014-08-11

A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV-vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL(-1) can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples. Copyright © 2014 Elsevier B.V. All rights reserved.

Selenium-mediated protection in reversing the sensitivity of bacterium to the bactericidal antibiotics.

PubMed

Li, Zhonglei; Tan, Jun; Shao, Lei; Dong, Xiaojing; Ye, Richard D; Chen, Daijie

2017-05-01

Inducing production of damaging reactive oxygen species (ROS) is an important criterion to distinguish the bactericidal antibiotics from bacteriostatic antibiotics. Selenoenzymes were generally recognized to be a powerful antioxidant capable of scavenging free radicals, protecting the cells from the harmful effects of ROS. Therefore, the present study was carried out to investigate the selenium (Se)-mediated protection in reversing antibiotic sensitivity and the role of selenoenzymes in alleviating the negative effects of oxidative stress. The cellular antioxidant activity of Se-enriched bacteria was analyzed, as well as intracellular ROS production and elimination when Se-enriched bacteria in the presence of various antibiotics. Compared to complete inhibition of the parental strain by bactericidal antibiotics, it only exhibited slight and reversible inhibition of Se-enriched Escherichia coli ATCC25922 and Staphylococcus aureus ATCC25923 at the same conditions, which indicated that intracellular selenium provided substantial protection against antibiotics. ROS generation caused by bactericidal antibiotics was confirmed by fluorescence spectrophotometry using 2', 7'-dichloro- uorescein diacetate (DCFH-DA) as substrate. The time course experiments of pretreatment with selenium showed significant decrease of ROS level at 2h. In summary, the present study provides experimental evidence supporting selenoenzymes has good scavenging effect to ROS and can protect bacteria from oxidative stress injury induced by bactericidal antibiotics. Copyright © 2017 Elsevier GmbH. All rights reserved.

Antibiotic susceptibility of probiotic strains: Is it reasonable to combine probiotics with antibiotics?

PubMed

Neut, C; Mahieux, S; Dubreuil, L J

2017-11-01

The main goal of this study was to determine the in vitro susceptibility of strains collected from marketed probiotics to antibiotics used to treat community-acquired infections. The minimum inhibitory concentrations (MICs) of 16 antibiotics were determined using a gradient strip (E test) or the agar dilution method for fidaxomicin. The probiotics demonstrated various antibiotic patterns. Bacterial probiotics are generally susceptible to most prescribed antibiotics orally administered, whereas yeast probiotics, such as Saccharomyces boulardii, are resistant. Special attention must be paid to co-prescriptions of antibiotics and probiotics to ensure that the probiotic strain is not susceptible. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Diversity of fecal coliforms and their antimicrobial resistance patterns in wastewater treatment model plant.

PubMed

Luczkiewicz, A; Fudala-Ksiazek, S; Jankowska, K; Quant, B; Olańczuk-Neyman, K

2010-01-01

The occurrence of resistance patterns among wastewater fecal coliforms was determined in the study. Susceptibility of the isolates was tested against 19 antimicrobial agents: aminoglycosides, aztreonam, carbapenems, cephalosporines, beta-lactam/beta-lactamase inhibitors, penicillines, tetracycline, trimethoprim/sulfamethoxazole, and fluoroquinolones. Additionally the removal of resistant isolates was evaluated in the laboratory-scale wastewater treatment model plant (M-WWTP), continuously supplied with the wastewater obtained from the full-scale WWTP. Number of fecal coliforms in raw (after mechanical treatment) and treated wastewater, as well as in aerobic chamber effluent was determined using selective medium. The selected strains were identified and examined for antibiotic resistance using Phoenix Automated Microbiology System (BD Biosciences, USA). The strains were identified as Escherichia coli (n=222), Klebsiella pneumoniae ssp. ozaenae (n=9), and Pantoea agglomerans (n=1). The isolate of P. agglomerans as well as 48% of E. coli isolates were sensitive to all antimicrobials tested. The most frequent resistance patterns were found for ampicillin: 100% of K. pneumoniae ssp. ozaenae and 41% of E. coli isolates. Among E. coli isolates 12% was regarded as multiple antimicrobial resistant (MAR). In the studied M-WWTP, the applied activated sludge processes reduced considerably the number of fecal coliforms, but increased the ratio of antimicrobial-resistant E. coli isolates to sensitive ones, especially among strains with MAR patterns.

Response of first-line antibiotic therapy in patients with febrile neutropenia during treatment of hematological disorders.

PubMed

Taj, M; Qureshi, R N; Farzana, T; Shamsi, T S; Ahmed, S S

2015-06-01

Patients with hematological disorders develop febrile neutropenia (FN); most of these events remain undetermined in origin. We performed a prospective study to determine the microbiological characteristics of infections and their response to the first-line antibiotic therapy in FN. The study was conducted at National Institute of Blood Disease and Bone Marrow Transplant. Two-hundred episodes of FN were assessed for the bacterial growth, antimicrobial susceptibility pattern and response to the first-line treatment of FN. All patients were given Ceftazidime and Amikacin Bosch Pharmaceutical (Pvt. Ltd), as first-line antibiotic in FN. Out of 200 episodes we had 108 clinically and microbiologically documented infections. The isolated frequencies for gram negative and gram positive organisms were n = 52 and 49 (48 and 45 %) respectively. Among gram negative micro-organisms, Escherichia coli (E. coli) was isolated in 15 (28.8 %), Klebsiella pneumonae in 4 (7.6 %) and Pseudomonas aeruginosa in 10 (19.2 %) were in highest frequencies. Methicillin sensitive staphylococci emerged as the frequently isolated gram-positive bacteria. Eight-one episodes (45.3 %) responded to the first-line treatment and death reported in 20 cases (10 %). Our study showed almost equal trend of gram positive and gram negative bacteria isolated from patients suffering from neutropenic fever. Empirical use of Ceftazidime and Amikacin as first-line antibiotics was able to cover the infection only in 45.3 % of episodes suffering from FN.

Recent patterns in antibiotic use for children with group A streptococcal infections in Japan.

PubMed

Okubo, Yusuke; Michihata, Nobuaki; Morisaki, Naho; Kinoshita, Noriko; Miyairi, Isao; Urayama, Kevin Y; Yasunaga, Hideo

2017-11-13

Antibiotics are the most frequently prescribed medicines for children, however inappropriate antibiotic prescribing is prevalent. This study investigated recent trends in antibiotic use and factors associated with appropriate antibiotic selection among children with group A streptococcal infections in Japan. Records of outpatients aged <18years with a diagnosis of group A streptococcal infection were obtained using the Japan Medical Data Center database. Prescription patterns for antibiotics were investigated and factors associated with penicillin use were evaluated using a multivariable log-binomial regression model. Overall, 5030 patients with a diagnosis of group A streptococcal infection were identified. The most commonly prescribed antibiotics were third-generation cephalosporins (53.3%), followed by penicillins (40.1%). In the multivariable log-binomial regression analysis, out-of-hours visits were independently associated with penicillin prescriptions [prevalence ratio (PR)=1.10, 95% confidence interval (CI) 1.03-1.18], whereas clinical departments other than paediatrics and internal medicine were related to non-penicillin prescriptions (PR=0.57, 95% CI 0.46-0.71). Third-generation cephalosporins were overprescribed for children with group A streptococcal infections. This investigation provides important information for promoting education for physicians and for constructing health policies for appropriate antibiotic prescription. Copyright © 2017. Published by Elsevier Ltd.

Pattern of Antibiotic Prescription for Oral Implant Treatment Among Dentists in Saudi Arabia.

PubMed

El-Kholey, Khalid E; Wali, Othman; Elkomy, Aamna; Almozayen, Ahmed

2018-06-01

To investigate antibiotic prophylaxis prescription behavior among dentists practicing dental implant surgery in Saudi Arabia. An observational questionnaire study was conducted in the period between October 2016 and December 2016. A link to an online previously validated questionnaire was sent to a convenience sample of dentists practicing dental implant placement in the different areas of Saudi Arabia. Absolute frequencies were used to describe the data. One hundred nine completed questionnaires were received. A total of 59.63% (n = 65) of the respondents routinely prescribed prophylactic antibiotics when performing implant surgery. There was a wide variation in the preoperative and postoperative prescription regimens with the majority (67%) starting the antibiotic immediately postoperatively for 3 to 5 days, with no preoperative antibiotic use. Amoxicillin and clavulanic acid combination was the drug of choice for 50.3% of the respondents, whereas 26.6% prescribed amoxicillin as the drug of choice. Although a small study with a low response rate, a wide variation in antibiotic prescribing patterns with respect to the drugs chosen, timing, and duration was found in implant surgery in Saudi Arabia. Dentists should be aware of the risk of antibiotic overuse and start to share in the efforts that aim to reserve the antibiotics to combat life-threatening infections and to reduce development of bacterial resistance to the available antibiotics.

[Antibiotic prescribing in acute respiratory tract infections in general practice].

PubMed

Malo, S; Bjerrum, L; Feja, C; Lallana, M J; Poncel, A; Rabanaque, M J

2015-06-01

Antimicrobial resistance is a worldwide threat to public health. Acute respiratory tract infections are the main reason for antibiotic prescribing in the Spanish paediatric population. The aim of the study was to describe the frequency of antibiotic prescription and their pattern of use in acute respiratory tract infections diagnosed in children in Primary Care in Aragón (Spain). A study was conducted over a 1-year period on children between 0 and 14 years-old, recording all episodes of acute otitis, acute pharyngotonsillitis, non-specific upper respiratory infection, and acute bronchitis. The proportion of episodes within each diagnosis receiving an antibiotic prescription was calculated, and the prescribing pattern was determined. Half (50%) of the children in Aragón were diagnosed with a respiratory tract infection during the study period. Non-specific upper respiratory infection was the most frequent diagnosis. An antibiotic was prescribed in 75% of pharyngotonsillitis episodes, 72% of otitis, 27% of bronchitis, and 16% of non-specific upper respiratory infections. Broad spectrum antibiotics, mainly amoxicillin and amoxicillin-clavulanic, were predominantly prescribed. Antibiotic prescribing in respiratory tract infections in children was generally high, and the choice of antibiotics was probably inappropriate in a high percentage of cases. Therefore an improvement in antibiotic prescribing in children appears to be needed. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

Prevalence and characterization of multi-drug resistant Salmonella Enterica serovar Gallinarum biovar Pullorum and Gallinarum from chicken

PubMed Central

Parvej, Md. Shafiullah; Nazir, K. H. M. Nazmul Hussain; Rahman, M. Bahanur; Jahan, Mueena; Khan, Mohammad Ferdousur Rahman; Rahman, Marzia

2016-01-01

Aim: Salmonella is an important zoonotic pathogen responsible for animal and human diseases. The aim of the present study was to determine the prevalence and stereotyping of Salmonella isolates isolated from apparently healthy poultry. Furthermore, the clonal relatedness among the isolated Salmonella serovars was assessed. Materials and Methods: A total of 150 cloacal swab samples from apparently healthy chickens were collected, and were subjected for the isolation and identification of associated Salmonella organisms. The isolated colonies were identified and characterized on the basis of morphology, cultural characters, biochemical tests, slide agglutination test, polymerase chain reaction, and pulsed-field gel electrophoresis (PFGE). Antibiotic sensitivity patterns were also investigated using commonly used antibiotics. Results: Of the 150 samples, 11 (7.33%) produced characteristics pink colony with black center on XLD agar medium, and all were culturally and biochemically confirmed to be Salmonella. All possessed serovar-specific gene SpeF and reacted uniformly with group D antisera, suggesting that all of the isolates were Salmonella Enterica serovar Gallinarum, biovar Pullorum and/or Gallinarum. Antimicrobial susceptibility testing revealed that 54.54% of the isolated Salmonella Enterica serovars were highly sensitive to ciprofloxacin, whereas the 81.81% isolates were resistant to amoxycillin, doxycycline, kanamycin, gentamycin, and tetracycline. Pulsed-field gel electrophoresis of the XbaI-digested genomic DNA exhibited identical banding patterns, suggesting that the multidrug resistant Salmonella Enterica serovars occurring in commercial layers are highly clonal in Bangladesh. Conclusion: The present study was conducted to find out the prevalence of poultry Salmonella in layer chicken and to find out the clonal relationship among them. The data in this study suggest the prevalence of Salmonella Enterica, which is multidrug resistant and highly clonal for commercial layers of Bangladesh. PMID:27051187

Propionibacterium acnes and antimicrobial resistance in acne.

PubMed

Dessinioti, Clio; Katsambas, Andreas

The human commensal bacterium Propionibacterium acnes (P. acnes) resides in the pilosebaceous duct of the skin. It has been long implicated in the pathogenesis of acne, although its exact role in the development of inflammatory acne lesions and in the formation of the microcomedo in the early stages of acne remains controversial. The worldwide prevalence of antibiotic-resistant P. acnes is increasing, with rates varying in different parts of the world. The reason for the difference in the antibiotic resistance patterns of P. acnes among different countries is not clear, although it may be attributed to different antibiotic prescribing habits, concomitant use of topical agents (retinoids, benzoyl peroxide, or other antibiotics), varying methods of bacterial sampling, or even different P. acnes populations. Although the relative abundances of P. acnes may be similar among patients with acne and individuals without acne, P. acnes populations and the presence of P. acnes biofilms differ, with different potential virulence properties and antimicrobial resistance patterns. Implications of the use of antibiotics and of antimicrobial resistance in patients with acne include the decreased efficacy of antibiotic treatments for acne, and the possible emergence of other resistant bacterial species via selective pressure by antibiotic use. Copyright © 2017 Elsevier Inc. All rights reserved.

Probing minority population of antibiotic-resistant bacteria.

PubMed

Huang, Tianxun; Zheng, Yan; Yan, Ya; Yang, Lingling; Yao, Yihui; Zheng, Jiaxin; Wu, Lina; Wang, Xu; Chen, Yuqing; Xing, Jinchun; Yan, Xiaomei

2016-06-15

The evolution and spread of antibiotic-resistant pathogens has become a major threat to public health. Advanced tools are urgently needed to quickly diagnose antibiotic-resistant infections to initiate appropriate treatment. Here we report the development of a highly sensitive flow cytometric method to probe minority population of antibiotic-resistant bacteria via single cell detection. Monoclonal antibody against TEM-1 β-lactamase and Alexa Fluor 488-conjugated secondary antibody were used to selectively label resistant bacteria green, and nucleic acid dye SYTO 62 was used to stain all the bacteria red. A laboratory-built high sensitivity flow cytometer (HSFCM) was applied to simultaneously detect the side scatter and dual-color fluorescence signals of single bacteria. By using E. coli JM109/pUC19 and E. coli JM109 as the model systems for antibiotic-resistant and antibiotic-susceptible bacteria, respectively, as low as 0.1% of antibiotic-resistant bacteria were accurately quantified. By monitoring the dynamic population change of a bacterial culture with the administration of antibiotics, we confirmed that under the antimicrobial pressure, the original low population of antibiotic-resistant bacteria outcompeted susceptible strains and became the dominant population after 5hours of growth. Detection of antibiotic-resistant infection in clinical urine samples was achieved without cultivation, and the bacterial load of susceptible and resistant strains can be faithfully quantified. Overall, the HSFCM-based quantitative method provides a powerful tool for the fundamental studies of antibiotic resistance and holds the potential to provide rapid and precise guidance in clinical therapies. Copyright © 2016 Elsevier B.V. All rights reserved.

A Community Intervention to Decrease Antibiotics Used for Self-Medication Among Latino Adults

PubMed Central

Mainous, Arch G.; Diaz, Vanessa A.; Carnemolla, Mark

2009-01-01

PURPOSE Recent evidence in Latino communities indicates substantial self-medication with antibiotics obtained without a prescription (WORx). We implemented and evaluated a culturally sensitive educational intervention to decrease antibiotic self-medication. METHODS We conducted a community-based intervention with preintervention and postintervention measures in the intervention community (Charleston, South Carolina) as well as a postintervention measure in a control community (Greenville, South Carolina) 200 miles away. The 9-month culturally sensitive intervention included multiple media sources (pamphlets, radio, newspapers). We evaluated the use of antibiotics WORx in the United States, as well as the likelihood of importing antibiotics, by surveying Latino adults in the intervention (n = 250) and in the control community (n = 250). RESULTS Most adults in the intervention community (69%) and the control community (60%) reported some exposure to messages about the inappropriate use of antibiotics, and 25.9% in the intervention community and 8.6% in the control community reported seeing our patient education pamphlets. A substantial proportion of Latino adults in both the intervention (31%) and control communities (20%) have obtained antibiotics WORx in the United States. In multivariate analyses, exposure to an educational message was not a significant predictor of having acquired antibiotics WORx in the United States in past 12 months. The primary predictor of respondents’ having acquired antibiotics WORx in the United States was whether they had bought antibiotics WORx outside the United States. CONCLUSIONS Novel approaches are needed to decrease the use of antibiotics WORx in Latino communities, as focusing only on education may not be sufficient to change behaviors common in their home countries. PMID:19901311

The effects of low-level ionizing radiation and copper exposure on the incidence of antibiotic resistance in lentic biofilm bacteria.

PubMed

McArthur, J Vaun; Dicks, Christian A; Bryan, A Lawrence; Tuckfield, R Cary

2017-09-01

Environmental reservoirs of antibiotic resistant bacteria are poorly understood. Understanding how the environment selects for resistance traits in the absence of antibiotics is critical in developing strategies to mitigate this growing menace. Indirect or co-selection of resistance by environmental pollution has been shown to increase antibiotic resistance. However no attention has been given to the effects of low-level ionizing radiation or the interactions between radiation and heavy metals on the maintenance or selection for antibiotic resistance (AR) traits. Here we explore the effect of radiation and copper on antibiotic resistance. Bacteria were collected from biofilms in two ponds - one impacted by low-level radiocesium and the other an abandoned farm pond. Through laboratory controlled experiments we examined the effects of increasing concentrations of copper on the incidence of antibiotic resistance. Differences were detected in the resistance profiles of the controls from each pond. Low levels (0.01 mM) of copper sulfate increased resistance but 0.5 mM concentrations of copper sulfate depressed the AR response in both ponds. A similar pattern was observed for levels of multiple antibiotic resistance per isolate. The first principal component response of isolate exposure to multiple antibiotics showed significant differences among the six isolate treatment combinations. These differences were clearly visualized through a discriminant function analysis, which showed distinct antibiotic resistance response patterns based on the six treatment groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

Accuracy of real-time PCR, Gram stain and culture for Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae meningitis diagnosis.

PubMed

Wu, Henry M; Cordeiro, Soraia M; Harcourt, Brian H; Carvalho, Mariadaglorias; Azevedo, Jailton; Oliveira, Tainara Q; Leite, Mariela C; Salgado, Katia; Reis, Mitermayer G; Plikaytis, Brian D; Clark, Thomas A; Mayer, Leonard W; Ko, Albert I; Martin, Stacey W; Reis, Joice N

2013-01-22

Although cerebrospinal fluid (CSF) culture is the diagnostic reference standard for bacterial meningitis, its sensitivity is limited, particularly when antibiotics were previously administered. CSF Gram staining and real-time PCR are theoretically less affected by antibiotics; however, it is difficult to evaluate these tests with an imperfect reference standard. CSF from patients with suspected meningitis from Salvador, Brazil were tested with culture, Gram stain, and real-time PCR using S. pneumoniae, N. meningitidis, and H. influenzae specific primers and probes. An antibiotic detection disk bioassay was used to test for the presence of antibiotic activity in CSF. The diagnostic accuracy of tests were evaluated using multiple methods, including direct evaluation of Gram stain and real-time PCR against CSF culture, evaluation of real-time PCR against a composite reference standard, and latent class analysis modeling to evaluate all three tests simultaneously. Among 451 CSF specimens, 80 (17.7%) had culture isolation of one of the three pathogens (40 S. pneumoniae, 36 N. meningitidis, and 4 H. influenzae), and 113 (25.1%) were real-time PCR positive (51 S. pneumoniae, 57 N. meningitidis, and 5 H. influenzae). Compared to culture, real-time PCR sensitivity and specificity were 95.0% and 90.0%, respectively. In a latent class analysis model, the sensitivity and specificity estimates were: culture, 81.3% and 99.7%; Gram stain, 98.2% and 98.7%; and real-time PCR, 95.7% and 94.3%, respectively. Gram stain and real-time PCR sensitivity did not change significantly when there was antibiotic activity in the CSF. Real-time PCR and Gram stain were highly accurate in diagnosing meningitis caused by S. pneumoniae, N. meningitidis, and H. influenzae, though there were few cases of H. influenzae. Furthermore, real-time PCR and Gram staining were less affected by antibiotic presence and might be useful when antibiotics were previously administered. Gram staining, which is inexpensive and commonly available, should be encouraged in all clinical settings.

Broad spectrum antibiotic enrofloxacin modulates contact sensitivity through gut microbiota in a murine model.

PubMed

Strzępa, Anna; Majewska-Szczepanik, Monika; Lobo, Francis M; Wen, Li; Szczepanik, Marian

2017-07-01

Medical advances in the field of infection therapy have led to an increasing use of antibiotics, which, apart from eliminating pathogens, also partially eliminate naturally existing commensal bacteria. It has become increasingly clear that less exposure to microbiota early in life may contribute to the observed rise in "immune-mediated" diseases, including autoimmunity and allergy. We sought to test whether the change of gut microbiota with the broad spectrum antibiotic enrofloxacin will modulate contact sensitivity (CS) in mice. Natural gut microbiota were modified by oral treatment with enrofloxacin prior to sensitization with trinitrophenyl chloride followed by CS testing. Finally, adoptive cell transfers were performed to characterize the regulatory cells that are induced by microbiota modification. Oral treatment with enrofloxacin suppresses CS and production of anti-trinitrophenyl chloride IgG1 antibodies. Adoptive transfer experiments show that antibiotic administration favors induction of regulatory cells that suppress CS. Flow cytometry and adoptive transfer of purified cells show that antibiotic-induced suppression of CS is mediated by TCR αβ + CD4 + CD25 + FoxP3 + Treg, CD19 + B220 + CD5 + IL-10 + , IL-10 + Tr1, and IL-10 + TCR γδ + cells. Treatment with the antibiotic induces dysbiosis characterized by increased proportion of Clostridium coccoides (cluster XIVa), C coccoides-Eubacterium rectale (cluster XIVab), Bacteroidetes, and Bifidobacterium spp, but decreased segmented filamentous bacteria. Transfer of antibiotic-modified gut microbiota inhibits CS, but this response can be restored through oral transfer of control gut bacteria to antibiotic-treated animals. Oral treatment with a broad spectrum antibiotic modifies gut microbiota composition and promotes anti-inflammatory response, suggesting that manipulation of gut microbiota can be a powerful tool to modulate the course of CS. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

[Epidemiological aspects relating to the determination of fosfomycin sensitivity: results of a study on 300 strains isolated in a hospital milieu in Turin].

PubMed

Vanini, G C; Moiraghi Ruggenini, A; Grassi, R; Maury, F; Giardini, F

1979-01-01

The AA. evaluated the sensitivity to Fosfomycin and to other commonly used antibiotics of 105 bacterial strains isolated from hospital environment and 195 from pathological materials. They also studied the problem of bacterial resistence to Fosfomycin considering the frequency of "inner colonies" and of bacterial cross-resistance to other antibiotics.

Comparison of epidemiological and antibiotic susceptibility pattern of metallo-Beta-lactamase-positive and metallo-Beta-lactamase-negative strains of pseudomonas aeruginosa.

PubMed

Ranjan, Shikha; Banashankari, Gs; Babu, Pr Sreenivasa

2014-07-01

The infections caused by metallo-beta-lactamases (MBLs) producing Pseudomonas aeruginosa are associated with higher rates of mortality, morbidity, and overall healthcare costs compared to non-MBL P. aeruginosa infections. To compare the epidemiologic factors and antibiograms of MBL-positive and MBL-negative P. aeruginosa isolates in a tertiary care hospital. In an observational study, from January 2011 to December 2012, all non-duplicate P. aeruginosa isolates were subjected to an antimicrobial sensitivity test against 10 antibiotics of five different classes. All P. aeruginosa strains showing resistance to at least one of the carbapenems were subjected to the MBL-E test. Epidemiological features and antibiograms of MBL-positive and MBL-negative strains were compared and statistically analyzed. Out of 350 isolates (total sample = 5330) of P. aeruginosa, MBL was detected in 58 isolates by the E-test, resulting in a prevalence of 16.57%. Resistance to most of the antibiotics was significantly higher in the MBL-positive strains with 100% resistance to ciprofloxacin, tobramycin, and meropenem, followed by imipenem (93.10%) and gentamicin (89.66%). The prevalence of multidrug-resistant and pandrug-resistant strains was significantly higher among the MBL group as compared to that in the non-MBL group ((55.17 vs. 7.88% (P < 0.0001) and 8.62 vs. 0.68% (P = 0.0006)), respectively. MBL-positive P. aeruginosa strains showed very high resistance to various antibiotics, as compared to the non-MBL strains. Increasing prevalence of MBL-producing isolates in hospital settings makes it important to perform routine detection of MBL-positive P. aeruginosa strains by in vitro testing before antibiotic use, for the purposes of infection prevention, and control, and for minimizing the adverse outcomes of infections with MBL-producing strains.

Cadmium tolerance and antibiotic resistance in Escherichia coli isolated from waste stabilization ponds.

PubMed

Patra, Sova; Das, T K; Avila, C; Cabello, V; Castillo, F; Sarkar, D; Lahiri, Susmita; Jana, B B

2012-04-01

The incidence pattern of cadmium tolerance and antibiotics resistance by Escherichia coli was examined periodically from the samples of water, sludge and intestine of fish raised in waste stabilization ponds in a sewage treatment plant. Samples of water and sludge were collected from all the selected ponds and were monitored for total counts of fecal coliform (FC), total coliform (TC) and the population of Escherichia coli, which was also obtained from the intestine of fishes. Total counts of both FC and TC as well as counts of E. coli were markedly reduced from the facultative pond to the last maturation pond. Tolerance limit to cadmium by E. coli tended to decline as the distance of the sewage effluent from the source increased; the effective lethal concentration of cadmium ranged from 0.1 mM in split chamber to 0.05 mM in first maturation pond. E. coli isolated from water, sludge and fish gut were sensitive to seven out of ten antibiotics tested. It appears that holistic functions mediated through the mutualistic growth of micro algae and heterotrophic bacteria in the waste stabilization ponds were responsible for the promotion of water quality and significant reduction of coliform along the sewage effluent gradient.

Surface plasmon resonance sensor for antibiotics detection based on photo-initiated polymerization molecularly imprinted array.

PubMed

Luo, Qiaohui; Yu, Neng; Shi, Chunfei; Wang, Xiaoping; Wu, Jianmin

2016-12-01

A surface plasmon resonance (SPR) sensor combined with nanoscale molecularly imprinted polymer (MIP) film as recognition element was developed for selective detection of the antibiotic ciprofloxacin (CIP). The MIP film on SPR sensor chip was prepared by in situ photo-initiated polymerization method which has the advantages of short polymerization time, controllable thickness and good uniformity. The surface wettability and thickness of MIP film on SPR sensor chip were characterized by static contact angle measurement and stylus profiler. The MIP-SPR sensor exhibited high selectivity, sensitivity and good stability for ciprofloxacin. The imprinting factors of the MIP-SPR sensor to ciprofloxacin and its structural analogue ofloxacin were 2.63 and 3.80, which is much higher than those to azithromycin, dopamine and penicillin. The SPR response had good linear relation with CIP concentration over the range 10 -11 -10 -7 molL -1 . The MIP-SPR sensor also showed good repeatability and stability during cyclic detections. On the basis of the photo-initiated polymerization method, a surface plasmon resonance imaging (SPRi) chip modified with three types of MIP sensing spots was fabricated. The MIPs-SPRi sensor shows different response patterns to ciprofloxacin and azithromycin, revealing the ability to recognize different antibiotic molecules. Copyright © 2016 Elsevier B.V. All rights reserved.

A New Approach for the Discovery of Antibiotics by Targeting Non-Multiplying Bacteria: A Novel Topical Antibiotic for Staphylococcal Infections

PubMed Central

Hu, Yanmin; Shamaei-Tousi, Alireza; Liu, Yingjun; Coates, Anthony

2010-01-01

In a clinical infection, multiplying and non-multiplying bacteria co-exist. Antibiotics kill multiplying bacteria, but they are very inefficient at killing non-multipliers which leads to slow or partial death of the total target population of microbes in an infected tissue. This prolongs the duration of therapy, increases the emergence of resistance and so contributes to the short life span of antibiotics after they reach the market. Targeting non-multiplying bacteria from the onset of an antibiotic development program is a new concept. This paper describes the proof of principle for this concept, which has resulted in the development of the first antibiotic using this approach. The antibiotic, called HT61, is a small quinolone-derived compound with a molecular mass of about 400 Daltons, and is active against non-multiplying bacteria, including methicillin sensitive and resistant, as well as Panton-Valentine leukocidin-carrying Staphylococcus aureus. It also kills mupirocin resistant MRSA. The mechanism of action of the drug is depolarisation of the cell membrane and destruction of the cell wall. The speed of kill is within two hours. In comparison to the conventional antibiotics, HT61 kills non-multiplying cells more effectively, 6 logs versus less than one log for major marketed antibiotics. HT61 kills methicillin sensitive and resistant S. aureus in the murine skin bacterial colonization and infection models. No resistant phenotype was produced during 50 serial cultures over a one year period. The antibiotic caused no adverse affects after application to the skin of minipigs. Targeting non-multiplying bacteria using this method should be able to yield many new classes of antibiotic. These antibiotics may be able to reduce the rate of emergence of resistance, shorten the duration of therapy, and reduce relapse rates. PMID:20676403

Diagnosis and Treatment of Typhoid Fever and Associated Prevailing Drug Resistance in Northern Ethiopia.

PubMed

Wasihun, Araya Gebreyesus; Wlekidan, Letemichael Negash; Gebremariam, Senay Aregawi; Welderufael, Abadi Luel; Muthupandian, Saravanan; Haile, Tadesse Dejenie; Dejene, Tsehaye Asmelash

2015-06-01

To determine diagnostic value of the Widal test, treatment pattern of febrile patients and antimicrobial drug susceptibility pattern of blood isolates. Using cross sectional methods, blood samples were collected for culture and Widal test from 502 febrile outpatients attending Mekelle hospital and Mekelle health center with similar symptoms to typhoid. Sensitivity, specificity for anti-TH and anti-TO titers using culture confirmed typhoid fever cases, and Kappa agreement between Titer and slide Widal tests were calculated. Treatment pattern of patients and antimicrobial susceptibility pattern of the blood isolates was assessed. From the 502 febrile patients, 8(1.6%) of them had culture-proven typhoid fever. However, patients who have results indicative of recent infection by O and H antigens of the Widal slide agglutination test were 343 (68.5%), with specificity and sensitivity of 33% and 100%, respectively. Over prescription of antibiotics was seen by Widal slide test for Ciprofloxacin 268 (76.1%), Amoxicillin- Clavulanic acid 9(2.6%), Amoxicillin 8(2.4%) and Chloranphenicol 8(2.4%). Tube titer positivity was seen in 23(5.3%) patients with 75% sensitivity and 95.8% specificity. Widal slide and Tube titer tests showed poor agreement for both antigens (kappa=0.02 for O) and (Kappa=0.09 for H). A single anti-TH titer of ≥ 1:160 and anti-TO titer ≥ 1:80 higher in our study showed an indication for typhoid fever infection. Drug resistance pattern of blood isolates ranges from 0-89.7% for gram positive and 0-100% for Gram negative, with an overall multi-drug resistance rate of 61.7%. Patients were wrongly diagnosed and treated for typhoid fever by Widal test. The tube titration method was relatively good but still had poor sensitivity. Blood isolates showed multi drug resistance, which may be due to the indiscriminate prescription as seen in this study. Based on our results, the slide Widal test is not helpful in the diagnosis of typhoid, hence other tests with rapid, feasible, better sensitivity and specificity are urgently needed in Ethiopia. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Travel Destinations and Sexual Behavior as Indicators of Antibiotic Resistant Shigella Strains--Victoria, Australia.

PubMed

Lane, Courtney R; Sutton, Brett; Valcanis, Mary; Kirk, Martyn; Walker, Cathryn; Lalor, Karin; Stephens, Nicola

2016-03-15

Knowledge of relationships between antibiotic susceptibility of Shigella isolates and travel destination or other risk factors can assist clinicians in determining appropriate antibiotic therapy prior to susceptibility testing. We describe relationships between resistance patterns and risk factors for acquisition in Shigella isolates using routinely collected data for notified cases of shigellosis between 2008 and 2012 in Victoria, Australia. We included all shigellosis patients notified during the study period, where Shigella isolates were tested for antimicrobial sensitivity using Clinical and Laboratory Standards Institute breakpoints. Cases were interviewed to collect data on risk factors, including recent travel. Data were analyzed using Stata 13.1 to examine associations between risk factors and resistant strains. Of the 500 cases of shigellosis, 249 were associated with overseas travel and 210 were locally acquired. Forty-six of 51 isolates of Indian origin displayed decreased susceptibility or resistance to ciprofloxacin. All isolates of Indonesian origin were susceptible to ciprofloxacin. Twenty-six travel-related isolates were resistant to all tested oral antimicrobials. Male-to-male sexual contact was the primary risk factor for 80% (120/150) of locally acquired infections among adult males, characterized by distinct periodic Shigella sonnei outbreaks. Clinicians should consider travel destination as a marker for resistance to common antimicrobials in returning travelers, where severe disease requires empirical treatment prior to receipt of individual sensitivity testing results. Repeated outbreaks of locally acquired shigellosis among men who have sex with men highlight the importance of prevention and control measures in this high-risk group. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Study of bacterial meningitis in children below 5 years with comparative evaluation of gram staining, culture and bacterial antigen detection.

PubMed

Yadhav Ml, Kala

2014-04-01

Bacterial meningitis is one of the most serious infections seen in infants and children, which is associated with acute complications and chronic morbidity. Infections of Central Nervous System (CNS) still dominate the scene of childhood neurological disorders in most of the developing tropical countries. To isolate, identify and determine the antibiotic susceptibility patterns of pathogens associated with bacterial meningitis. We also aimed to comparatively evaluate of Gram staining, culture and bacterial antigen detection in cerebrospinal fluid samples. Present comparative study included 100 CSF samples of children below the age of 5 years, who were clinically suspected meningitis cases. The samples were subjected to Gram staining, culture and Latex agglutination test (LAT). The organisms isolated in the study were characterized and antibiotic susceptibility test was done according to standard guidelines. It was done by using Gaussian test. Of the 100 cases, 24 were diagnosed as Acute bacterial meningitis (ABM) cases by. Gram staining, culture and latex agglutination test. 21 (87.5%) cases were culture positive, with 2 cases being positive for polymicrobial isolates. Gram staining was positive in 17 (70.53%) cases and LAT was positive in 18 (33.33%) cases. Streptococcus pneumoniae was the predominant organism which was isolated and it was sensitive to antibiotics. In the present study, male to female ratio was 1.27:1, which showed a male preponderance. With the combination of Gram staining, culture, and LAT, 100% sensitivity and specificity can be achieved (p < 0.001). Gram staining and LAT can detect 85% of cases of ABM. Bacterial meningitis is a medical emergency and making an early diagnosis and providing treatment early are life saving and they reduce chronic morbidity.

Clinical and molecular epidemiology of chromosome-mediated resistance to third-generation cephalosporins in Enterobacter isolates in eastern France.

PubMed

Talon, D; Bailly, P; Bertrand, X; Thouverez, M; Mulin, B

2000-07-01

To determine both the prevalence of group I beta-lactamase-related resistance and the clinical setting in which resistance to expanded-spectrum cephalosporins occurs. Isolates of Enterobacter spp. were sensitivity tested to a range of antibiotics, and selected isolates were DNA fingerprinted by pulsed-field gel electrophoresis. The medical records of all patients with positive cultures for Enterobacter spp. were reviewed to determine the effect of previous antibiotic treatment on the susceptibility profile of these organisms. The crude incidence of colonization/infection (n = 315) was 0.51 per 100 patients and 0.73 per 1000 days of hospitalization. The 4-day and 7-day Kaplan-Meier rates of colonization/infection with Enterobacter were estimated to be 7.57% (standard deviation (SD = 3.26%) and 4.16% (SD = 2.88%)), respectively. The time lag to colonization/infection with isolates producing large amounts of Bush group 1 beta-lactamase (HLBL) (27.35 +/- 27.30 days) was significantly different from that to colonization/infection with wild-type isolates (13.59 +/- 17.93 days) (P = 0.036). Ninety-six isolates (30.5%) demonstrated acquired resistance to expanded-spectrum cephalosporins: 34 isolates (10.8%) produced extended-spectrum beta-lactamase, and 62 isolates (19.7%) produced HLBL. The 89 Enterobacter isolates susceptible to third-generation cephalosporins yielded 84 major DNA patterns, and the 45 HLBL isolates yielded 38 major DNA patterns. The risk of colonization/infection with HLBL-producing Enterobacter was higher in cases of antimicrobial treatment with third-generation cephalosporins or a fluoroquinolone, and in cases of urinary tract colonization/infection. The judicious use in hospitals of both expanded-spectrum cephalosporins and other antibiotics such as fluoroquinolones is necessary to curtail the emergence of resistance in Enterobacter spp.

Does adding antibiotics to cement reduce the need for early revision in total knee arthroplasty?

PubMed

Bohm, Eric; Zhu, Naisu; Gu, Jing; de Guia, Nicole; Linton, Cassandra; Anderson, Tammy; Paton, David; Dunbar, Michael

2014-01-01

There is considerable debate about whether antibiotic-loaded bone cement should be used for fixation of TKAs. While antibiotics offer the theoretical benefit of lowering early revision due to infection, they may weaken the cement and thus increase the likelihood of aseptic loosening, perhaps resulting in a higher revision rate. We (1) compared the frequency of early knee revision arthroplasty in patients treated with antibiotic-loaded or non-antibiotic-loaded cement for initial fixation, (2) determined effects of age, sex, comorbidities, and surgeons' antibiotic-loaded cement usage patterns on revision rate, and (3) compared causes of revision (aseptic or septic) between groups. Our study sample was taken from the Canadian Joint Replacement Registry and Canada's Hospital Morbidity Database and included cemented TKAs performed between April 1, 2003, and March 31, 2008, including 20,016 TKAs inserted with non-antibiotic-loaded cement and 16,665 inserted with antibiotic-loaded cement. Chi-square test was used to compare the frequency of early revisions between groups. Cox regression modeling was used to determine whether revision rate would change by age, sex, comorbidities, or use of antibiotic-loaded cement. Similar Cox regression modeling was used to compare cause of revision between groups. Two-year revision rates were similar between the groups treated with non-antibiotic-loaded cement and antibiotic-loaded cement (1.40% versus 1.51%, p = 0.41). When controlling for age, sex, comorbidities, diabetes, and surgeons' antibiotic-loaded cement usage patterns, the revision risk likewise was similar between groups. Revision rates for infection were similar between groups; however, there were more revisions for aseptic loosening in the group treated with non-antibiotic-loaded cement (p = 0.02). The use of antibiotic-loaded cement in TKAs performed for osteoarthritis has no clinically significant effect on reducing revision within 2 years in patients who received perioperative antibiotics. Longer followup and confirmation of these findings with other national registries are warranted.

A Saccharomyces cerevisiae genome-wide mutant screen for sensitivity to 2,4-diacetylphloroglucinol, a biocontrol antibiotic produced by Pseudomonas fluorescens

USDA-ARS?s Scientific Manuscript database

Strains of Pseudomonas fluorescens that produce the antibiotic 2,4-diacetylphloroglucinol (DAPG) are biocontrol agents of a variety of soilborne pathogens. DAPG is active against a broad spectrum of organisms ranging from bacteria to higher plants. This suggests that the antibiotic may target basic...

Saccharomyces cerevisiae genome-wide mutant screen for sensitivity to 2,4-diacetylphloroglucinol, a biocontrol antibiotic produced by Pseudomonas fluorescens

USDA-ARS?s Scientific Manuscript database

2,4-diacetylphloroglucinol (2,4-DAPG) is an antibiotic produced by Pseudomonas fluorescens that plays a key role in the ability of the bacterium to suppress phytopathogenic fungi. 2,4-DAPG has broad antibiotic activity, affecting organisms ranging from bacteria to higher plants. The biosynthesis and...

[Using cluster analysis for evaluation of sensitivity to antibiotics of pathogens isolated from women with genital inflammatory diseases].

PubMed

Tsyganenko, A Ia; Kon', E V

2007-01-01

The study was conducted to evaluate sensitivity to 44 antibiotics of pathogens isolated from 183 women with genital inflammatory diseases and to offer schemes of antibacterial treatment. The pathogens (66.8%) were in associations. The probability of isolation of main bacteria and sexually transmitted microorganisms in different associations was estimated in the work. Using the methods of clustering analysis all the tested antibiotics were divided into 3 groups, depending on their antimicrobial activity toward bacteria isolated both in monoculture and in associations. Furagin, cefotaxime, gentamicin, cefoperazon, ceftriaxon, ciprofloxacin, pefloxacin, as well as, cefazolin, zoxan, ofloxacin, and lomefloxacin were shown to be the most effective antibiotics in vitro. The least activity was diplayed by ectericid, chlorophillipt, and ampiox. These data should be considered when choosing the antibacterial treatment of genital inflammatory diseases.

The Impact of Policy Guidelines on Hospital Antibiotic Use over a Decade: A Segmented Time Series Analysis

PubMed Central

Chandy, Sujith J.; Naik, Girish S.; Charles, Reni; Jeyaseelan, Visalakshi; Naumova, Elena N.; Thomas, Kurien; Lundborg, Cecilia Stalsby

2014-01-01

Introduction Antibiotic pressure contributes to rising antibiotic resistance. Policy guidelines encourage rational prescribing behavior, but effectiveness in containing antibiotic use needs further assessment. This study therefore assessed the patterns of antibiotic use over a decade and analyzed the impact of different modes of guideline development and dissemination on inpatient antibiotic use. Methods Antibiotic use was calculated monthly as defined daily doses (DDD) per 100 bed days for nine antibiotic groups and overall. This time series compared trends in antibiotic use in five adjacent time periods identified as ‘Segments,’ divided based on differing modes of guideline development and implementation: Segment 1– Baseline prior to antibiotic guidelines development; Segment 2– During preparation of guidelines and booklet dissemination; Segment 3– Dormant period with no guidelines dissemination; Segment 4– Booklet dissemination of revised guidelines; Segment 5– Booklet dissemination of revised guidelines with intranet access. Regression analysis adapted for segmented time series and adjusted for seasonality assessed changes in antibiotic use trend. Results Overall antibiotic use increased at a monthly rate of 0.95 (SE = 0.18), 0.21 (SE = 0.08) and 0.31 (SE = 0.06) for Segments 1, 2 and 3, stabilized in Segment 4 (0.05; SE = 0.10) and declined in Segment 5 (−0.37; SE = 0.11). Segments 1, 2 and 4 exhibited seasonal fluctuations. Pairwise segmented regression adjusted for seasonality revealed a significant drop in monthly antibiotic use of 0.401 (SE = 0.089; p<0.001) for Segment 5 compared to Segment 4. Most antibiotic groups showed similar trends to overall use. Conclusion Use of overall and specific antibiotic groups showed varied patterns and seasonal fluctuations. Containment of rising overall antibiotic use was possible during periods of active guideline dissemination. Wider access through intranet facilitated significant decline in use. Stakeholders and policy makers are urged to develop guidelines, ensure active dissemination and enable accessibility through computer networks to contain antibiotic use and decrease antibiotic pressure. PMID:24647339

Perioperative antibiotic usage by facial plastic surgeons: national survey results and comparison with evidence-based guidelines.

PubMed

Grunebaum, Lisa Danielle; Reiter, David

2006-01-01

To determine current practice for use of perioperative antibiotics among facial plastic surgeons, to determine the extent of use of literature support for preferences of facial plastic surgeons, and to compare patterns of use with nationally supported evidence-based guidelines. A link to a Web site containing a questionnaire on perioperative antibiotic use was e-mailed to more than 1000 facial plastic surgeons in the United States. Responses were archived in a dedicated database and analyzed to determine patterns of use and methods of documenting that use. Current literature was used to develop evidence-based recommendations for perioperative antibiotic use, emphasizing current nationally supported guidelines. Preferences varied significantly for medication used, dosage and regimen, time of first dose relative to incision time, setting in which medication was administered, and procedures for which perioperative antibiotic was deemed necessary. Surgical site infection in facial plastic surgery can be reduced by better conformance to currently available evidence-based guidelines. We offer specific recommendations that are supported by the current literature.

The Composition and Spatial Patterns of Bacterial Virulence Factors and Antibiotic Resistance Genes in 19 Wastewater Treatment Plants

PubMed Central

Zhang, Bing; Xia, Yu; Wen, Xianghua; Wang, Xiaohui; Yang, Yunfeng; Zhou, Jizhong; Zhang, Yu

2016-01-01

Bacterial pathogenicity and antibiotic resistance are of concern for environmental safety and public health. Accumulating evidence suggests that wastewater treatment plants (WWTPs) are as an important sink and source of pathogens and antibiotic resistance genes (ARGs). Virulence genes (encoding virulence factors) are good indicators for bacterial pathogenic potentials. To achieve a comprehensive understanding of bacterial pathogenic potentials and antibiotic resistance in WWTPs, bacterial virulence genes and ARGs in 19 WWTPs covering a majority of latitudinal zones of China were surveyed by using GeoChip 4.2. A total of 1610 genes covering 13 virulence factors and 1903 genes belonging to 11 ARG families were detected respectively. The bacterial virulence genes exhibited significant spatial distribution patterns of a latitudinal biodiversity gradient and a distance-decay relationship across China. Moreover, virulence genes tended to coexist with ARGs as shown by their strongly positive associations. In addition, key environmental factors shaping the overall virulence gene structure were identified. This study profiles the occurrence, composition and distribution of virulence genes and ARGs in current WWTPs in China, and uncovers spatial patterns and important environmental variables shaping their structure, which may provide the basis for further studies of bacterial virulence factors and antibiotic resistance in WWTPs. PMID:27907117

Antimicrobial Resistance in Enterococcus spp. Isolated from Environmental Samples in an Area of Intensive Poultry Production

PubMed Central

Furtula, Vesna; Jackson, Charlene R.; Farrell, Erin Gwenn; Barrett, John B.; Hiott, Lari M.; Chambers, Patricia A.

2013-01-01

Enterococcus spp. from two poultry farms and proximate surface and ground water sites in an area of intensive poultry production were tested for resistance to 16 clinical antibiotics. Resistance patterns were compared to assess trends and possible correlations for specific antimicrobials and levels of resistance. Enterococci were detected at all 12 surface water sites and three of 28 ground water sites. Resistance to lincomycin, tetracycline, penicillin and ciprofloxacin in poultry litter isolates was high (80.3%, 65.3%, 61.1% and 49.6%, respectively). Resistance in the surface water to the same antibiotics was 87.1%, 24.1%, 7.6% and 12.9%, respectively. Overall, 86% of litter isolates, 58% of surface water isolates and 100% of ground water isolates were resistant to more than one antibiotic. Fifty-four different resistance patterns were recognised in isolates obtained from litter and environmental samples and several E. faecium and E. faecalis isolates from litter and environment samples shared the same resistance pattern. Multiple antibiotic resistant (MAR) indices calculated to assess health risks due to the presence of resistant enterococci suggested an increased presence of antibiotics in surface water, likely from poultry sources as no other wastewater contributions in the area were documented. PMID:23481592

Microbiology and antimicrobial susceptibility of otitis externa: a changing pattern of antimicrobial resistance.

PubMed

Heward, E; Cullen, M; Hobson, J

2018-04-01

Otitis externa is a common presentation to secondary care otolaryngology clinics. Despite this, few studies have investigated the microbiology and antimicrobial resistance of otitis externa. This study aimed to examine these issues. Analysis identified 302 swabs taken from 217 patients (100 male, 117 female), between 1 January 2015 and 30 March 2016, at our rapid access otolaryngology clinic. In total, 315 organisms were isolated; the most frequent was Pseudomonas aeruginosa (31.1 per cent), followed by candida species (22.9 per cent) and Staphylococcus aureus (11.7 per cent). P aeruginosa was sensitive to ciprofloxacin in 97.7 per cent of cases and to gentamicin in 78.4 per cent. Compared with studies worldwide, the relative proportions of different organisms causing otitis externa and the patterns of antimicrobial resistance differ. Increasing resistance of P aeruginosa to aminoglycosides demonstrates a changing pattern of antimicrobial resistance that has not been previously reported. Reassuringly, quinolone antibiotics remain highly effective when treating P aeruginosa.

Diverse Gene Cassettes in Class 1 Integrons of Facultative Oligotrophic Bacteria of River Mahananda, West Bengal, India

PubMed Central

Chakraborty, Ranadhir; Kumar, Arvind; Bhowal, Suparna Saha; Mandal, Amit Kumar; Tiwary, Bipransh Kumar; Mukherjee, Shriparna

2013-01-01

Background In this study a large random collection (n = 2188) of facultative oligotrophic bacteria, from 90 water samples gathered in three consecutive years (2007–2009) from three different sampling sites of River Mahananda in Siliguri, West Bengal, India, were investigated for the presence of class 1 integrons and sequences of the amplification products. Methodology/Principal Findings Replica plating method was employed for determining the antibiotic resistance profile of the randomly assorted facultative oligotrophic isolates. Genomic DNA from each isolate was analyzed by PCR for the presence of class 1 integron. Amplicons were cloned and sequenced. Numerical taxonomy and 16S rRNA gene sequence analyses were done to ascertain putative genera of the class 1 integron bearing isolates. Out of 2188 isolates, 1667 (76.19%) were antibiotic-resistant comprising of both single-antibiotic resistance (SAR) and multiple-antibiotic resistant (MAR), and 521 (23.81%) were sensitive to all twelve different antibiotics used in this study. Ninety out of 2188 isolates produced amplicon(s) of varying sizes from 0.15 to 3.45 KB. Chi-square (χ2) test revealed that the possession of class 1 integron in sensitive, SAR and MAR is not equally probable at the 1% level of significance. Diverse antibiotic-resistance gene cassettes, aadA1, aadA2, aadA4, aadA5, dfrA1, dfrA5, dfrA7, dfrA12, dfrA16, dfrA17, dfrA28, dfrA30, dfr-IIe, blaIMP-9, aacA4, Ac-6′-Ib, oxa1, oxa10 and arr2 were detected in 64 isolates. The novel cassettes encoding proteins unrelated to any known antibiotic resistance gene function were identified in 26 isolates. Antibiotic-sensitive isolates have a greater propensity to carry gene cassettes unrelated to known antibiotic-resistance genes. The integron-positive isolates under the class Betaproteobacteria comprised of only two genera, Comamonas and Acidovorax of family Comamonadaceae, while isolates under class Gammaproteobacteria fell under the families, Moraxellaceae, Pseudomonadaceae, Aeromonadaceae and Enterobacteriaceae. Conclusions Oligotrophic bacteria are good sources of novel genes as well as potential reservoirs of antibiotic resistance gene casettes. PMID:23951238

Reconsidering the Current Preterm Premature Rupture of Membranes Antibiotic Prophylactic Protocol.

PubMed

Wolf, Maya Frank; Miron, Dan; Peleg, David; Rechnitzer, Hagai; Portnov, Igor; Salim, Raed; Keness, Yoram; Reich, Dan; Ami, Moshe Ben; Peretz, Avi; Koshnir, Amir; Shachar, Inbar Ben

2015-11-01

The purpose of our study was to determine whether the current antibiotic regimen for preterm premature rupture of membranes (PPROM) is adequate for covering the current causative agents and sensitivities of chorioamnionitis and early-onset neonatal sepsis. During a 3-year period, we retrieved the results from placental and amniotic membrane cultures obtained at delivery in cases of maternal fever, chorioamnionitis, and PPROM, and from blood cultures obtained from neonates with early-onset sepsis (EOS) in three participating hospitals. Sensitivity of pathogens to antimicrobial agents was performed using routine microbiologic techniques. There were 1,133 positive placental or amniotic cultures, 740 (65.3%) were from gram-negative Enterobacteriaceae. There were 27 neonates diagnosed with EOS with positive blood cultures. Aerobic Enterobacteriaceae accounted for 14 cases (52%) and group B streptococcus for 7 cases (26%). Of the Escherichia coli and Klebsiella sp., only 38% were sensitive to ampicillin. Local pathogens and their antibiotic sensitivity profiles should be explored every few years and an effective antibiotic protocol chosen to cover the main pathogens causing chorioamnionitis and EOS. Consideration should be made for changing ampicillin in women with PPROM to a regimen with better coverage of gram-negative Enterobacteriaceae. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Whole genome and transcriptome analyses of environmental antibiotic sensitive and multi-resistant Pseudomonas aeruginosa isolates exposed to waste water and tap water

PubMed Central

Schwartz, Thomas; Armant, Olivier; Bretschneider, Nancy; Hahn, Alexander; Kirchen, Silke; Seifert, Martin; Dötsch, Andreas

2015-01-01

The fitness of sensitive and resistant Pseudomonas aeruginosa in different aquatic environments depends on genetic capacities and transcriptional regulation. Therefore, an antibiotic-sensitive isolate PA30 and a multi-resistant isolate PA49 originating from waste waters were compared via whole genome and transcriptome Illumina sequencing after exposure to municipal waste water and tap water. A number of different genomic islands (e.g. PAGIs, PAPIs) were identified in the two environmental isolates beside the highly conserved core genome. Exposure to tap water and waste water exhibited similar transcriptional impacts on several gene clusters (antibiotic and metal resistance, genetic mobile elements, efflux pumps) in both environmental P. aeruginosa isolates. The MexCD-OprJ efflux pump was overexpressed in PA49 in response to waste water. The expression of resistance genes, genetic mobile elements in PA49 was independent from the water matrix. Consistently, the antibiotic sensitive strain PA30 did not show any difference in expression of the intrinsic resistance determinants and genetic mobile elements. Thus, the exposure of both isolates to polluted waste water and oligotrophic tap water resulted in similar expression profiles of mentioned genes. However, changes in environmental milieus resulted in rather unspecific transcriptional responses than selected and stimuli-specific gene regulation. PMID:25186059

Multifaceted antibiotic treatment analysis of methicillin-sensitive Staphylococcus aureus bloodstream infections.

PubMed

Weber, Zhanni; Ariano, Robert; Lagacé-Wiens, Philippe; Zelenitsky, Sheryl

2016-12-01

Given the overall prevalence and poor prognosis of Staphylococcus aureus bloodstream infections (BSIs), the study of treatment strategies to improve patient outcomes is important. The aim of this study was to conduct a multifaceted antibiotic treatment analysis of methicillin-sensitive S. aureus (MSSA) BSI and to characterise optimal early antibiotic therapy (within the first 7 days of drawing the index blood culture) for this serious infection. Antibiotic selection was categorised as optimal targeted (intravenous cloxacillin or cefazolin), optimal broad (piperacillin/tazobactam or meropenem), adequate (vancomycin) or inadequate (other antibiotics or oral therapy). A TSE (timing, selection, exposure) score was developed to comprehensively characterise early antibiotic therapy, where higher points corresponded to prompt initiation, optimal antibiotic selection and longer exposure (duration). Amongst 71 cases of complicated MSSA-BSI, end-of-treatment (EOT) response (i.e. clinical cure) was improved when at least adequate antibiotic therapy was initiated within 24 h [71.7% (33/46) vs. 48.0% (12/25); P = 0.047]. Clinical cure was also more likely when therapy included ≥4 days of optimal targeted antibiotics within the first 7 days [74.4% (29/39) vs. 50.0% (16/32); P = 0.03]. The TSE score was an informative index of early antibiotic therapy, with EOT cure documented in 72.0% (36/50) compared with 42.9% (9/21) of cases with scores above and below 15.2, respectively (P = 0.02). In multivariable analysis, lower Charlson comorbidity index, presence of BSI on admission, and optimising early antibiotic therapy, as described above, were associated with clinical cure in patients with MSSA-BSI. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Assessment of Antibiotic Utilization Pattern in Treatment of Acute Diarrhoea Diseases in Bishoftu General Hospital, Oromia Ethiopia.

PubMed

Tulu, Selamawit; Tadesse, Tarekegne; Alemayehu Gube, Addisu

2018-01-01

Majority of acute diarrhoeal diseases are self-limiting and do not require routine treatment. Treatment with empirical antimicrobials is recommended only for dysenteric and invasive bacterial diarrhoea. Irrational use of antibiotics in treatment of acute diarrhoea is common in clinical practice worldwide. This study was carried out to assess the pattern of antibiotic use for acute diarrhoeal diseases in Bishoftu General Hospital, East Shewa Ethiopia. Institution based cross-sectional study was conducted from April 1 to April 30, 2016. Data were collected retrospectively from patients treated for diarrhoeal diseases from January 2015 to December 2015 using structured questionnaires and entered into SPSS (IBM 20) and descriptive statistics was carried out. Among the 303 patients, 51.2% were males and 48.8% were females. Of them, 62% were children under five years. Two hundred sixty three (86.8%) patients received eight different types of antibiotics and cotrimoxazole (178 patients, 58.7%) was the most prescribed antibiotics, followed by ciprofloxacin (33, 10.9%) and amoxicillin (14, 4.6%). Based on the presence of blood in stools, 14.5% of cases were of invasive bacterial type. According to the recommendations of WHO, the rate of overuse of antibiotics was 72.3%. This study revealed that there was high overuse of antibiotics for both adults and children under five with acute diarrhoea in Bishoftu General Hospital. And Cotrimoxazole was the most prescribed antibiotic.

General Practitioner trainers prescribe fewer antibiotics in primary care: Evidence from France.

PubMed

Devillers, Louise; Sicsic, Jonathan; Delbarre, Angelique; Le Bel, Josselin; Ferrat, Emilie; Saint Lary, Olivier

2018-01-01

Antibiotic prescription is a central public health issue. Overall, 90% of antibiotic prescriptions are delivered to patients in ambulatory care, and a substantial proportion of these prescriptions could be avoided. General Practitioner (GP) trainers are similar to other GPs in terms of sociodemographic and medical activities, but they may have different prescription patterns. Our aim was to compare the antibiotic prescribing rates between GP trainers and non-trainers. This observational cross-sectional study was conducted on administrative data claims from the French National Health Insurance. The antibiotic prescribing rate was calculated. The main independent variable was the training status of the GPs. Prescribing rates were adjusted for the various GPs' characteristics (gender, age, location of the practice, number of visits per GP and the case-mix) in a multiple linear regression analysis. Between June 2014 and July 2015 the prescribing patterns of 860 GPs were analysed, among which 102 were GP trainers (12%). Over the year 363,580 patients were prescribed an antibiotic out of 3,499,248 visits for 1,299,308 patients seen over the year thus representing around 27.5% of patients. In the multivariate analyses, being a trainer resulted in a significant difference of 6.62 percentage points (IC 95%: [-8.55; -4.69]; p<0.001) in antibiotic prescriptions comparing to being a non-trainer, corresponding to a relative reduction of 23.4%. These findings highlight the role of GP trainers in antibiotic prescriptions. By prescribing fewer antibiotics and influencing the next generations of GPs, the human and economic burden of antibiotics could be reduced.

Worldwide pattern of antibiotic prescription in endodontic infections.

PubMed

Segura-Egea, Juan José; Martín-González, Jenifer; Jiménez-Sánchez, María Del Carmen; Crespo-Gallardo, Isabel; Saúco-Márquez, Juan José; Velasco-Ortega, Eugenio

2017-08-01

Odontogenic infections, and especially endodontic infections, are polymicrobial, involving a combination of Gram-positive and Gram-negative facultative anaerobes and strictly anaerobic bacteria. Therefore, antibiotics can be used as an adjunct to endodontic treatment. However, most chronic and even acute endodontic infections can be successfully managed by disinfection of the root-canal system, which eliminates the source of infection, followed by abscess drainage or tooth extraction, without the need for antibiotics. The literature provides evidence of inadequate prescribing practices by dentists. The aim of this concise review was to analyse the worldwide pattern of antibiotic prescription in endodontic infections. Comprehensive searches were conducted in MEDLINE/PubMed, Wiley Online Database, Web of Science and Scopus. The databases were searched up to 13 March 2016 for studies in which dentists used systemic antibiotics to treat endodontic lesions and which reported data on the type of antibiotic prescribed and on the diagnosis of the endodontic disease treated. The electronic and hand searches identified 69 titles, of which 25 were included in the final analysis. Amoxicillin was reported as the drug of choice for endodontic infections in most countries, and clindamycin and erythromycin were the choice for patients allergic to penicillin. Dentists worldwide prescribe antibiotics for non-indicated conditions, such as pulpitis. Antibiotics are overprescribed for the management of endodontic infections. It is necessary to improve antibiotic-prescribing habits in the treatment of endodontic infections, as well as to introduce educational initiatives to encourage the coherent and proper use of antibiotics in such conditions. © 2017 FDI World Dental Federation.

Leukocyte Agglomeration Reaction in Diagnosis of Allergy Reactions from Antibiotics,

DTIC Science & Technology

tested in a clinic on 80 patients with serious allergic anamnesis . The results of the studies indicate that the leukocyte agglomeration reaction is a highly sensitive immunological indicator of hypersensitivity to antibiotics.

[Molecular characterization and antimicrobial susceptibility pattern of extended-spectrum β-lactamase-producing Escherichia coli as cause of community acquired urinary tract infection].

PubMed

Galindo-Méndez, Mario

Background Community acquired urinary tract infections (CaUTI) caused by strains of extended-spectrum β-lactamases (ESBL) - producing Escherichia coli, mainly by strains carrying the blaCTX-M-15 gene, is a growing phenomenon worldwide. Aim To determine the antibiotic susceptibility pattern of ESBL-producing E. coli as cause of CaUTI and to identify their molecular pattern. Methods A descriptive study was performed in the city of Oaxaca, Mexico, from where 288 strains of CaUTI-producing strains of E. coli in adults with possible UTI were isolated. The CLSI criteria was followed to determine the antimicrobial susceptibility patterns, and their molecular characterization was performed by using PCR. Results 31.3% of E. coli strains isolated in our population were ESBL producers, which presented higher levels of antibiotic resistance than those of non-producers of these enzymes. 95.6% of the studied strains were carriers of the blaCTX-M gene. Conclusions One-third of the Ca-UTI caused by E. coli in our population are caused by ESBL-producing strains, which present high levels of resistance to the antibiotics widely used in our community. This situation considerably decreases the number of antibiotics available for an empiric treatment against these infections.

Prevalence of multidrug-resistant, coagulase-positive Staphylococcus aureus in nasal carriage, food, wastewater and paper currency in Jalandhar city (north-western), an Indian state of Punjab.

PubMed

Kumar, Harsh; Palaha, Rajdeep; Kaur, Navreet; Ratnakar, Wankhede Swapnil; Sodi, Aakanksha; Kaur, Manmeet; Katiyar, Richa; Sharma, Mamta; Kaur, Charanpreet; Kumar, Virendra

2015-01-01

Development of multidrug-resistant pattern in the bacterial community is a major threat to the society. Staphylococcus aureus is perhaps the pathogen of the greatest concern because of its inherent virulence, its ability to cause a diverse array of life-threatening situations and capacity to adapt to different environmental conditions. The aims of this study is to investigate the multidrug-resistant pattern of the coagulase-positive S. aureus isolated from nasal carriage, food, paper currency and wastewater samples. We had also studied the multiple antibiotic resistance index and in vitro production of β-lactamase. The study had found out 130 coagulase-positive S. aureus strains isolated from total of 595 samples such as anterior nares of preschool children (195), hospital nurses (100), drivers (76), food (86), wastewater (3) and paper currency (135) (Indian rupee). The biotypes pattern were as follows; A > D > B > C> UT. Multiple antibiotic resistance (MAR) value clearly defines the multidrug-resistant pattern of the S. aureus among different sources. Statistical analysis (one-way ANOVA) of results obtained indicated that the difference in the antibiotic resistance observed in the 130 bacterial isolates against the 23 different antibiotics used in this study was statically significant (p < 0.01).

Antibacterial resistance patterns of pediatric community-acquired urinary infection: Overview.

PubMed

Konca, Capan; Tekin, Mehmet; Uckardes, Fatih; Akgun, Sadik; Almis, Habip; Bucak, Ibrahim Hakan; Genc, Yeliz; Turgut, Mehmet

2017-03-01

Urinary tract infection (UTI) is common in children. The aim of this study was therefor to construct a guide for the empirical antibiotic treatment of community-acquired UTI by investigating the etiology and antimicrobial resistance patterns of uropathogens and analyzing the epidemiological and clinical patient characteristics. A total of 158 children with positive urine culture were included in the study. Antibiotic susceptibility testing was performed with Vitek 2 Compact for 28 commonly used antimicrobials. Mean age was 3.36 ± 3.38 years (range, 45 days-15 years). Escherichia coli (60.1%), and Klebsiella spp. (16.5%) were the most common uropathogens. For all Gram-negative isolates, a high level of resistance was found against ampicillin/sulbactam (60.1%), trimethoprim/sulfamethoxazole (44.2%), cefazolin (36.2%), cefuroxime sodium (33.5%), and amoxicillin/clavulanate (31.5%). A low level of resistance was noted against cefepime (8.7%), ertapenem (4.6%), norfloxacin (1.3%), and meropenem (0.7%). There was no resistance against amikacin. There is high antibiotic resistance in children with UTI. The patterns of uropathogen antimicrobial resistance vary in susceptibility to antimicrobials depending on region and time. Thus, the trends of antibiotic susceptibility patterns should be analyzed periodically to select the appropriate regimen for UTI treatment. © 2016 Japan Pediatric Society.

[Interrelation of the antibiotic sensitivity (resistance) of staphylococci, clinical forms of the infection and production of protein A].

PubMed

Fomenko, G A

1984-06-01

Two hundred and thirty-two strains of Staph. aureus isolated from patients with staphylococcal infections were studied. The strains were isolated from the blood of patients with sepsis, from the purulent foci on the skin and in the subcutaneous fat, from the nasopharyngeal mucosa of patients with tonsillitis and inflammation of the upper respiratory tract, from the sputum of patients with the pneumonia signs and from the pus of patients with otitis. The pathogens were identified with the routine methods. The quantitative content of protein A in the strains was determined by the method of indirect hemagglutination with red blood cells sensitized with the hemolytic serum. The data obtained were analysed with regard to the strain group and characteristics of the strain resistance or sensitivity to benzylpenicillin, erythromycin, oleandomycin, chloramphenicol, streptomycin, neomycin, kanamycin, monomycin, ristomycin and furagin K. Statistically significant differences in the protein A content in certain strain groups were observed. These differences might be correlated with the strain antibiotic resistance but not sensitivity. Pronounced changes in the levels of protein A were detected in the staphylococcal hemocultures resistant to erythromycin and streptomycin. The cultures resistant to erythromycin were characterized by decreased content of protein A and those resistant to streptomycin were characterized by increased content of protein A. Comparison of the antibiotic sensitivity of the strains of 5 groups by variation statistics revealed significant differences in the levels of sensitivity to streptomycin, neomycin, kanamycin, monomycin, ristomycin and furagin K but not to erythromycin, oleandomycin and chloramphenicol in the strains of certain groups. The staphylococcal hemocultures isolated from patients with sepsis proved to be the most sensitive to the antibiotics.

Fate and Effect of Antibiotics in Beef and Dairy Manure during Static and Turned Composting.

PubMed

Ray, Partha; Chen, Chaoqi; Knowlton, Katharine F; Pruden, Amy; Xia, Kang

2017-01-01

Manure composting has general benefits for production of soil amendment, but the effects of composting on antibiotic persistence and effects of antibiotics on the composting process are not well-characterized, especially for antibiotics commonly used in dairy cattle. This study provides a comprehensive, head-to-head, replicated comparison of the effect of static and turned composting on typical antibiotics used in beef and dairy cattle in their actual excreted form and corresponding influence on composting efficacy. Manure from steers (with or without chlortetracycline, sulfamethazine, and tylosin feeding) and dairy cows (with or without pirlimycin and cephapirin administration) were composted at small scale (wet mass: 20-22 kg) in triplicate under static and turned conditions adapted to represent US Food and Drug Administration guidelines. Thermophilic temperature (>55°C) was attained and maintained for 3 d in all composts, with no measureable effect of compost method on the pattern, rate, or extent of disappearance of the antibiotics examined, except tylosin. Disappearance of all antibiotics, except pirlimycin, followed bi-phasic first-order kinetics. However, individual antibiotics displayed different fate patterns in response to the treatments. Reduction in concentration of chlortetracycline (71-84%) and tetracycline (66-72%) was substantial, while near-complete removal of sulfamethazine (97-98%) and pirlimycin (100%) was achieved. Tylosin removal during composting was relatively poor. Both static and turned composting were generally effective for reducing most beef and dairy antibiotic residuals excreted in manure, with no apparent negative impact of antibiotics on the composting process, but with some antibiotics apparently more recalcitrant than others. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

The aminoglycoside antibiotic kanamycin damages DNA bases in Escherichia coli: caffeine potentiates the DNA-damaging effects of kanamycin while suppressing cell killing by ciprofloxacin in Escherichia coli and Bacillus anthracis.

PubMed

Kang, Tina Manzhu; Yuan, Jessica; Nguyen, Angelyn; Becket, Elinne; Yang, Hanjing; Miller, Jeffrey H

2012-06-01

The distribution of mutants in the Keio collection of Escherichia coli gene knockout mutants that display increased sensitivity to the aminoglycosides kanamycin and neomycin indicates that damaged bases resulting from antibiotic action can lead to cell death. Strains lacking one of a number of glycosylases (e.g., AlkA, YzaB, Ogt, KsgA) or other specific repair proteins (AlkB, PhrB, SmbC) are more sensitive to these antibiotics. Mutants lacking AlkB display the strongest sensitivity among the glycosylase- or direct lesion removal-deficient strains. This perhaps suggests the involvement of ethenoadenine adducts, resulting from reactive oxygen species and lipid peroxidation, since AlkB removes this lesion. Other sensitivities displayed by mutants lacking UvrA, polymerase V (Pol V), or components of double-strand break repair indicate that kanamycin results in damaged base pairs that need to be removed or replicated past in order to avoid double-strand breaks that saturate the cellular repair capacity. Caffeine enhances the sensitivities of these repair-deficient strains to kanamycin and neomycin. The gene knockout mutants that display increased sensitivity to caffeine (dnaQ, holC, holD, and priA knockout mutants) indicate that caffeine blocks DNA replication, ultimately leading to double-strand breaks that require recombinational repair by functions encoded by recA, recB, and recC, among others. Additionally, caffeine partially protects cells of both Escherichia coli and Bacillus anthracis from killing by the widely used fluoroquinolone antibiotic ciprofloxacin.

The persistence of antibiotic resistance: evaluation of a probiotic approach using antibiotic-sensitive M. elsdenii strains to prevent colonization of swine by antibiotic-resistant strains

USDA-ARS?s Scientific Manuscript database

Megasphaera elsdenii is a lactate-fermenting, obligately anaerobic bacterium commonly present in the gastrointestinal tracts of mammals, including humans. Swine M. elsdenii strains were previously shown to have high levels of tetracycline resistance (MIC = 64->256 micro g/ml) and to carry mosaic (re...

Uncomplicated E Coli Urinary Tract Infection in College Women: A Follow-Up Study of E Coli Sensitivities to Commonly Prescribed Antibiotics

ERIC Educational Resources Information Center

Ansbach, Robert K.; Dybus, Karen; Bergeson, Rachel

2005-01-01

Treatment of uncomplicated urinary tract infections (UTIs) has changed in the past few years with researchers advocating empiric treatment for shorter periods of time without the use of cultures. Researchers report that antibiotic resistance of Escherichia coli (E coli) to commonly prescribed antibiotics in uncomplicated UTIs has been increasing.…

How Nature Morphs Peptide Scaffolds into Antibiotics

PubMed Central

Nolan, Elizabeth M.; Walsh, Christopher T.

2010-01-01

The conventional notion that peptides are poor candidates for orally available drugs because of protease-sensitive peptide bonds, intrinsic hydrophilicity, and ionic charges contrasts with the diversity of antibiotic natural products with peptide-based frameworks that are synthesized and utilized by Nature. Several of these antibiotics, including penicillin and vancomycin, are employed to treat bacterial infections in humans and have been best-selling therapeutics for decades. Others might provide new platforms for the design of novel therapeutics to combat emerging antibiotic-resistant bacterial pathogens. PMID:19058272

Elongation factor Tu resistant to kirromycin in an Esherichia coli mutant altered in both tuf genes

PubMed Central

Fischer, Eckhard; Wolf, Heinz; Hantke, Klaus; Parmeggiani, Andrea

1977-01-01

A mutant of Escherichia coli is described that displays kirromycin resistance in a cell-free system by virtue of an altered elongation factor Tu (EF-Tu). In poly(U)-directed poly(Phe) synthesis the kirromycin resistance of the crystallized enzyme ranged between a factor of 80 and 700, depending on temperature. Similarly, kirromycin-induced EF-Tu GTPase activity uncoupled from ribosomes and aminoacyl-tRNA required correspondingly higher concentrations of the antibiotic. Resistance of EF-Tu to kirromycin is a consequence of a modified enzyme structure as indicated by its altered fingerprint pattern. P1 transduction experiments showed that the kirromycin-resistant EF-Tu is coded by an altered tufB gene (tufB1). The known existence of two genes coding for EF-Tu would interfere with the recognition of a mutant altered in only one of those genes, if the mutation were recessive. Because kirromycin blocks EF-Tu release from the ribosome, kirromycin sensitivity is dominant, as shown by the failure of a mixed EF-Tu population to express resistance in vitro. Therefore, phenotypic expression of kirromycin resistance in vivo appears to be only possible if the EF-Tu mutant lacks an active tufA gene, a property likely to be inherited from the parental D22 strain. The observations that introduction of a tufA+ region makes the resistant strain sensitive to the antibiotic and that transduction of tufB1 into a recipient other than E. coli D22 yields kirromycin-sensitive progeny support these conclusions. Images PMID:337296

Drug susceptibility and treatment response of common urinary tract infection pathogens in children.

PubMed

Chen, Pei-Chun; Chang, Luan-Yin; Lu, Chun-Yi; Shao, Pei-Lan; Tsai, I-Jung; Tsau, Yong-Kwei; Lee, Ping-Ing; Chen, Jong-Ming; Hsueh, Po-Ren; Huang, Li-Min

2014-12-01

To document the trends of sensitivity and to find whether it is necessary to change antibiotics in selected patients according to the sensitivity test results in our clinical practice. We collected urine culture results from 0-18-year-old patients in the National Taiwan University Hospital from January 1, 2003 to October 31, 2012. Their medical chart was reviewed to identify true pathogens responsible for their urinary tract infection (UTI). We checked the percentage of susceptibility of these pathogens to ampicillin, amoxicillin-clavulanate (AMC), cefazolin, cefmetazole, ceftriaxone, gentamicin, and trimethoprim-sulfamethoxazole (TMP-SMX) according to the Clinical and Laboratory Standards Institute (CLSI) guideline. The extended-spectrum-beta-lactamases (ESBLs) rate was also checked. In addition, we reviewed the treatment response of different antibiotics. Defervescence within 48 hours after initial antibiotics use was considered responsive. A total of 7758 urine cultures positive for Escherichia coli infection were collected during the 10-year period. The E. coli cefazolin susceptibility rate was 62-73% during 2003-2010, but it dropped to 23% in 2011 and 28% in 2012 after the new CLSI guideline (M100-S21) was released. However, other antibiotics did not show a significant difference. In UTI caused by E. coli, on average, the sensitivity rates for various antibiotics were as follows: cefmetazole, 90%; ceftriaxone, 85%; gentamicin, 77%; AMC, 61%; TMP-SMX, 47%; and ampicillin, 20%. The ESBL rate was also found to increase (2-11%; p < 0.01). The overall response rate of UTI caused by E. coli to first-line antibiotics such as first-generation cephalosporin and/or gentamicin was 78%. The susceptibility of common urinary tract pathogens to cefazolin has decreased dramatically since 2010. This trend may be due to the change in the CLSI guideline. Although the susceptibility rate to first-line empirical antibiotics shows a decreasing trend, we found that the clinical response was acceptable for our first-line empirical antibiotics. Copyright © 2013. Published by Elsevier B.V.

Prescribing patterns and associated factors of antibiotic prescription in primary health care facilities of Kumbo East and Kumbo West Health Districts, North West Cameroon

PubMed Central

Chem, Elvis Dzelamonyuy; Anong, Damian Nota; Akoachere, Jane-Francis K. T.

2018-01-01

Background Inappropriate use of antibiotics is a global public health challenge and has been associated with antibiotic resistance. WHO reports show that efforts to promote rational antibiotic use in developing countries are poor. With the growing number of infections with antibiotic resistant bacteria, rational drug use becomes imperative and studies that promote rational drug use are highly necessary. Considering this, we investigated prescribing patterns and predictors of antibiotic prescription in primary health care facilities in Kumbo East (KE) and Kumbo West (KW) health districts in North West Cameroon, to contribute data which could influence policy on antibiotic use. Methods and findings A cross sectional retrospective study was conducted from April 2014 to April 2015 in 26 randomly selected primary care facilities. Questionnaires were administered to 59 antibiotic prescribers to determine factors that predict antibiotic prescribing. Data on antibiotic prescription were collected by review of consultation registers. Prescription rates and demographics, prescriber and institution factors were analyzed using ANOVA. The best predictor of prescription was determined using multiple linear regression analysis. Results A total of 30,096 prescriptions were reviewed. Overall antibiotic prescription rate was 36.71%, with a mean of 1.14 antibiotics prescribed per patient. Amoxicillin was the most prescribed (29.9%). The most prevalent indications for prescribing were respiratory tract infections (21.27%). All antibiotics prescribed were broad-spectrum. Antibiotics were prescribed for patients with malaria and also in situations where diagnosis was uncertain. Prescribing by generic name was 98.36% while 99.87% was from Essential Drug List. Use of laboratory results, patient turnout and Performance Based Financing (PBF) were significantly associated with antibiotic prescribing rates (p < 0.05). PBF moderated prescribing. Conclusion There was misuse of antibiotics in primary care facilities in study area. We recommend all primary care health facilities in study area to be included in the PBF scheme and that prescribing should only be done by physicians as the have adequate training. PMID:29505584

An assessment of antibiotic therapy of urinary tract infection in elderly, hospitalised patients.

PubMed

McCaig, D J; Stewart, D; Harvey, Y; Downie, G; Scott, C J

1995-11-01

The aim of the study was to compare the antibiotic treatment actually received by elderly, hospitalised patients with urinary tract infection (UTI) with 'optimal' therapy (as gauged by compliance with antibiotic policy, infecting organism, sensitivity data, patient renal function and cost). UTI was more common in females and in catheterised patients and E.Coli was the commonest pathogen. Trimethoprim and co-amoxiclav were the drugs used most frequently for either empirical or sensitivity data-based treatment. In 96% of infections a drug with appropriate action was administered. Often, however, treatment could have been optimised by substituting a cheaper suitable antibiotic, by standardising duration of therapy and ensuring that doses were adjusted for renal impairment. Savings from the use of 'optimal' therapy were estimated at 17%. There is clearly considerable scope for positive input from the clinical pharmacist in this area.

[The role of heavy metals and their derivatives in the selection of antibiotics resistant gram-negative rods (author's transl)].

PubMed

Joly, B; Cluzel, R

1975-01-01

The authors have studied 116 Gram-negative strains, 27 of which were sensitive to antibiotics and 89 showed multiple resistance. The MIC of mercury chloride, mercuric nitrate and of an aqueous solution of mercuresceine were much higher in the case of the sensitive strains. The transfer of resistance to mercury, which has been achieved in 56% of cases, was always accompanied by transfer of resistance to the antibiotics. The MIC of phenylmercury borate, mercurothiolic acid and other heavy metals (such as: cobaltous nitrate, silver nitrate, cadmium nitrate, nickel nitrate, zinc nitrate, copper sulphate and sodium arsenate) are approximatively the same for all strains. The normal concentrations of mercury in nature are lower than the rate of microbial selection. But in areas of accumulation, particularly in biological chains or in hospitals, the mercury compounds could play a part in the selection of antibiotic resistant Gram-negative bacteria.

Influences on the start, selection and duration of treatment with antibiotics in long-term care facilities

PubMed Central

Daneman, Nick; Campitelli, Michael A.; Giannakeas, Vasily; Morris, Andrew M.; Bell, Chaim M.; Maxwell, Colleen J.; Jeffs, Lianne; Austin, Peter C.; Bronskill, Susan E.

2017-01-01

BACKGROUND: Understanding the extent to which current antibiotic prescribing behaviour is influenced by clinicians’ historical patterns of practice will help target interventions to optimize antibiotic use in long-term care. Our objective was to evaluate whether clinicians’ historical prescribing behaviours influence the start, prolongation and class selection for treatment with antibiotics in residents of long-term care facilities. METHODS: We conducted a retrospective cohort study of all physicians who prescribed to residents in long-term care facilities in Ontario between Jan. 1 and Dec. 31, 2014. We examined variability in antibiotic prescribing among physicians for 3 measures: start of treatment with antibiotics, use of prolonged durations exceeding 7 days and selection of fluoroquinolones. Funnel plots with control limits were used to determine the extent of variation and characterize physicians as extreme low, low, average, high and extreme high prescribers for each tendency. Multivariable logistic regression was used to assess whether a clinician’s prescribing tendency in the previous year predicted current prescribing patterns, after accounting for residents’ demographics, comorbidity, functional status and indwelling devices. RESULTS: Among 1695 long-term care physicians, who prescribed for 93 132 residents, there was wide variability in the start of antibiotic treatment (median 45% of patients, interquartile range [IQR] 32%–55%), use of prolonged treatment durations (median 30% of antibiotic prescriptions, IQR 19%–46%) and selection of fluoroquinolones (median 27% of antibiotic prescriptions, IQR 18%–37%). Prescribing tendencies for antibiotics by physicians in 2014 correlated strongly with tendencies in the previous year. After controlling for individual resident characteristics, prior prescribing tendency was a significant predictor of current practice. INTERPRETATION: Physicians prescribing antibiotics exhibited individual, measurable and historical tendencies toward start of antibiotic treatment, use of prolonged treatment duration and class selection. Prescriber audit and feedback may be a promising tool to optimize antibiotic use in long-term care facilities. PMID:28652480

Antibiotic consumption in non-teaching Lebanese hospitals: A cross-sectional study.

PubMed

Iskandar, Katia; Hanna, Pierre A; Salameh, Pascale; Raad, Etwal B

2016-01-01

The rising threat of antibiotic resistance is linked to patterns of antibiotic use in hospital settings where global efforts are undertaken to encourage reporting and benchmarking antibiotic consumption in an attempt to improve prescription regimens. In Lebanon, where data concerning the level of antibiotic consumption in hospitals is scarce, the aim of our paper is to track the intensity of antibiotic consumption in order to identify potential evidence of antibiotic misuse or abuse. The study is conducted in 2012 for a period of 12-month using data from pharmacy records in 27 non-teaching Lebanese hospitals according to the Anatomical, Therapeutic and chemical classification system and Defined Daily Dose (ATC/DDD) recommended by the World Health Organization and compiling data on ABC Calc software version 3.1. Results show that the average antibiotic consumption excluding pediatric cases is 72.56 Defined Daily Dose per 100 Bed-Days (DDD/100BD). Total broad spectrum antibiotic consumption is 12.14 DDD/100BD with no significant difference found between public and private hospitals (p>0.05 for all). The most commonly used antibiotics were Amoxycillin/Clavulanic acid, Ceftriaxone, Amoxycillin and Cefuroxime for parenteral use. Consumption of beta-lactams, Cephalosporins, Carbapenems, Monobactams and quinolones did not vary significantly by region, occupancy rate, number of beds including the number of intensive care unit beds. Our data findings provides baseline information on patterns of antibiotic consumption in Lebanon and the issue calls for concerted efforts to encourage data reporting on national basis and to correlate future findings with results of antibiotic susceptibility testing which can provide insights and tools needed to assess the public health consequences of antimicrobial misuse and to evaluate the impact of antibiotic resistance containment interventions. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Influences on the start, selection and duration of treatment with antibiotics in long-term care facilities.

PubMed

Daneman, Nick; Campitelli, Michael A; Giannakeas, Vasily; Morris, Andrew M; Bell, Chaim M; Maxwell, Colleen J; Jeffs, Lianne; Austin, Peter C; Bronskill, Susan E

2017-06-26

Understanding the extent to which current antibiotic prescribing behaviour is influenced by clinicians' historical patterns of practice will help target interventions to optimize antibiotic use in long-term care. Our objective was to evaluate whether clinicians' historical prescribing behaviours influence the start, prolongation and class selection for treatment with antibiotics in residents of long-term care facilities. We conducted a retrospective cohort study of all physicians who prescribed to residents in long-term care facilities in Ontario between Jan. 1 and Dec. 31, 2014. We examined variability in antibiotic prescribing among physicians for 3 measures: start of treatment with antibiotics, use of prolonged durations exceeding 7 days and selection of fluoroquinolones. Funnel plots with control limits were used to determine the extent of variation and characterize physicians as extreme low, low, average, high and extreme high prescribers for each tendency. Multivariable logistic regression was used to assess whether a clinician's prescribing tendency in the previous year predicted current prescribing patterns, after accounting for residents' demographics, comorbidity, functional status and indwelling devices. Among 1695 long-term care physicians, who prescribed for 93 132 residents, there was wide variability in the start of antibiotic treatment (median 45% of patients, interquartile range [IQR] 32%-55%), use of prolonged treatment durations (median 30% of antibiotic prescriptions, IQR 19%-46%) and selection of fluoroquinolones (median 27% of antibiotic prescriptions, IQR 18%-37%). Prescribing tendencies for antibiotics by physicians in 2014 correlated strongly with tendencies in the previous year. After controlling for individual resident characteristics, prior prescribing tendency was a significant predictor of current practice. Physicians prescribing antibiotics exhibited individual, measurable and historical tendencies toward start of antibiotic treatment, use of prolonged treatment duration and class selection. Prescriber audit and feedback may be a promising tool to optimize antibiotic use in long-term care facilities. © 2017 Canadian Medical Association or its licensors.

Seasonal and temporal variation in release of antibiotics in hospital wastewater: estimation using continuous and grab sampling.

PubMed

Diwan, Vishal; Stålsby Lundborg, Cecilia; Tamhankar, Ashok J

2013-01-01

The presence of antibiotics in the environment and their subsequent impact on resistance development has raised concerns globally. Hospitals are a major source of antibiotics released into the environment. To reduce these residues, research to improve knowledge of the dynamics of antibiotic release from hospitals is essential. Therefore, we undertook a study to estimate seasonal and temporal variation in antibiotic release from two hospitals in India over a period of two years. For this, 6 sampling sessions of 24 hours each were conducted in the three prominent seasons of India, at all wastewater outlets of the two hospitals, using continuous and grab sampling methods. An in-house wastewater sampler was designed for continuous sampling. Eight antibiotics from four major antibiotic groups were selected for the study. To understand the temporal pattern of antibiotic release, each of the 24-hour sessions were divided in three sub-sampling sessions of 8 hours each. Solid phase extraction followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS) was used to determine the antibiotic residues. Six of the eight antibiotics studied were detected in the wastewater samples. Both continuous and grab sampling methods indicated that the highest quantities of fluoroquinolones were released in winter followed by the rainy season and the summer. No temporal pattern in antibiotic release was detected. In general, in a common timeframe, continuous sampling showed less concentration of antibiotics in wastewater as compared to grab sampling. It is suggested that continuous sampling should be the method of choice as grab sampling gives erroneous results, it being indicative of the quantities of antibiotics present in wastewater only at the time of sampling. Based on our studies, calculations indicate that from hospitals in India, an estimated 89, 1 and 25 ng/L/day of fluroquinolones, metronidazole and sulfamethoxazole respectively, might be getting released into the environment per 100 hospital beds.

The antibiotic susceptibility patterns of uropathogens among children with urinary tract infection in Shiraz.

PubMed

Pouladfar, Gholamreza; Basiratnia, Mitra; Anvarinejad, Mojtaba; Abbasi, Pejman; Amirmoezi, Fatemeh; Zare, Samaneh

2017-09-01

Urinary tract infection (UTI) is one of the most common bacterial infections in pediatrics. Delay in diagnosis and treatment can cause significant morbidity. The physicians knowledge regarding the symptoms, microorganisms that caused UTI, and effective antibiotics in a geographical area can help them to select the appropriate antibiotics. This study was performed to determine the prevalence of bacteria that cause UTI and their susceptibility to common antibiotics as well as the common symptoms and associated factors in children of Shiraz, Southern Iran.This cross sectional study was performed among 202 children with UTI, aged 2 months to 18 years old, between August and November 2014 in pediatric medical centers of Shiraz University of Medical Sciences. Urine samples were collected using urinary catheter or suprapubic in children < 2 years and mid-stream in children over 2 years, respectively. The type of micro-organisms causing UTI was determined and evaluation of antibiotic susceptibility for each organism was assayed by the Kirby Bauer method using antibiogram test. Patient's information was collected through checking the medical documents and interview with parents.Our results showed that the frequency of UTI was significantly higher in girls (70.3%) than in boys. The most commonly discovered pathogens were Escherichia coli (E coli) (51.5%), followed by Klebsiella spp. (16.8%), and Enterococcus spp. (9.9%). Overall susceptibility test showed the highest resistance to ampicillin (81.2%) and cotrimoxazole (79.2%), and the highest sensitivity to imipenem (90.1%) and Gentamicin (65.3%). Gram negative and positive bacteria showed the highest antibiotic resistance to amoxicillin (83.8%) and clindamycin (100%), respectively. In addition, production of extended spectrum beta lactamase (ESBL) was 69.2% and 30.8% in E coli and Kelebsiella respectively.The efficacy of third generation of the cephalosporins was reduced because of the high rate of production of ESBL and drug resistance. These results inform the physician as to which antibiotics are appropriate to prescribe for the patient, as well as urine culture reports and following the patient's clinical response so that high antimicrobial resistance is not developed at the community level.

The antibiotic susceptibility patterns of uropathogens among children with urinary tract infection in Shiraz

PubMed Central

Pouladfar, Gholamreza; Basiratnia, Mitra; Anvarinejad, Mojtaba; Abbasi, Pejman; Amirmoezi, Fatemeh; Zare, Samaneh

2017-01-01

Abstract Urinary tract infection (UTI) is one of the most common bacterial infections in pediatrics. Delay in diagnosis and treatment can cause significant morbidity. The physician's knowledge regarding the symptoms, microorganisms that caused UTI, and effective antibiotics in a geographical area can help them to select the appropriate antibiotics. This study was performed to determine the prevalence of bacteria that cause UTI and their susceptibility to common antibiotics as well as the common symptoms and associated factors in children of Shiraz, Southern Iran. This cross sectional study was performed among 202 children with UTI, aged 2 months to 18 years old, between August and November 2014 in pediatric medical centers of Shiraz University of Medical Sciences. Urine samples were collected using urinary catheter or suprapubic in children < 2 years and mid-stream in children over 2 years, respectively. The type of micro-organisms causing UTI was determined and evaluation of antibiotic susceptibility for each organism was assayed by the Kirby Bauer method using antibiogram test. Patient's information was collected through checking the medical documents and interview with parents. Our results showed that the frequency of UTI was significantly higher in girls (70.3%) than in boys. The most commonly discovered pathogens were Escherichia coli (E coli) (51.5%), followed by Klebsiella spp. (16.8%), and Enterococcus spp. (9.9%). Overall susceptibility test showed the highest resistance to ampicillin (81.2%) and cotrimoxazole (79.2%), and the highest sensitivity to imipenem (90.1%) and Gentamicin (65.3%). Gram negative and positive bacteria showed the highest antibiotic resistance to amoxicillin (83.8%) and clindamycin (100%), respectively. In addition, production of extended spectrum beta lactamase (ESBL) was 69.2% and 30.8% in E coli and Kelebsiella respectively. The efficacy of third generation of the cephalosporins was reduced because of the high rate of production of ESBL and drug resistance. These results inform the physician as to which antibiotics are appropriate to prescribe for the patient, as well as urine culture reports and following the patient's clinical response so that high antimicrobial resistance is not developed at the community level. PMID:28906365

Ambulatory consolidation chemotherapy for acute myeloid leukemia with antibacterial prophylaxis is associated with frequent bacteremia and the emergence of fluoroquinolone resistant E. Coli

PubMed Central

2013-01-01

Background Ambulatory consolidation chemotherapy for acute myeloid leukemia (AML) is frequently associated with bloodstream infections but the spectrum of bacterial pathogens in this setting has not been well-described. Methods We evaluated the emergence of bacteremias and their respective antibiotic susceptibility patterns in AML patients receiving ambulatory-based consolidation therapy. Following achievement of complete remission, 207 patients received the first cycle (C1), and 195 the second cycle (C2), of consolidation on an ambulatory basis. Antimicrobial prophylaxis consisted of ciprofloxacin, amoxicillin and fluconazole. Results There were significantly more positive blood cultures for E. coli in C2 as compared to C1 (10 vs. 1, p=0.0045); all E. coli strains for which susceptibility testing was performed demonstrated resistance to ciprofloxacin. In patients under age 60 there was a significantly higher rate of Streptococccus spp. bacteremia in C2 vs. C1; despite amoxicillin prophylaxis all Streptococcus isolates in C2 were sensitive to penicillin. Patients with Staphylococcus bacteremia in C1 had significantly higher rates of Staphylococcus bacteremia in C2 (p=0.009, OR=8.6). Conclusions For AML patients undergoing outpatient-based intensive consolidation chemotherapy with antibiotic prophylaxis, the second cycle is associated with higher rates of ciprofloxacin resistant E. coli, penicillin-sensitive Streptococcus bacteremias and recurrent Staphylococcus infections. PMID:23800256

Arcobacter Isolation from Minced Beef Samples in Costa Rica.

PubMed

Córdoba-Calderón, Oscar; Redondo-Solano, Mauricio; Castro-Arias, Eduardo; Arias-EchandI, María Laura

2017-04-03

The presence of Arcobacter spp. in minced meat (including beef) samples has been well documented in different countries, with varying frequencies. Nevertheless, the only Latin American country reporting this bacterium in minced beef samples is Mexico, with a 28.8% frequency in 2003. Previous studies in Costa Rica have demonstrated the presence of Arcobacter species in samples taken from the poultry production chain, but still there are no studies performed in bovine meat. The aim of this study was to determine the frequency of this bacterium in 120 samples of minced beef acquired from the Central Valley region of Costa Rica and to describe the antibiotic sensitivity pattern of the isolates obtained. A total of 75 different Arcobacter strains were isolated from minced beef samples, for a final frequency of 48.3%. After species PCR identification, the strains were classified as A. butzleri (37.3%), A. cibarius (14.7%), A. thereius (12%), and Arcobacter spp. (36%). All samples were sensitive to gentamicin but were resistant to ampicillin, levofloxacin, nalidixic acid, and ciprofloxacin. The results obtained in this study show that the frequency of isolation of Arcobacter in minced beef samples is high and that there is a high resistance rate for antibiotics in common use. This suggests that Arcobacter represents a health risk for Costa Rica and that control measures should be developed to decrease its potential impact.

The path of least resistance in oral surgery.

PubMed

Fee, Laura

2016-01-01

Antibiotic resistance is an imminent threat to worldwide public health. Dental professionals must demonstrate judicious use of antibiotics and educate their patients about the risks associated with their overuse. PURPOSE OF THE PAPER: To encourage the dental profession to prescribe responsibly in order to optimise the use of antibiotics in oral surgery. Antibiotic stewardship programmes are recommended to help reduce the emergence of infections that are multidrug-resistant. Clinical practice audits are encouraged to help dentists ensure conservative prescribing patterns. The dental profession has a duty of care to prescribe antibiotics in adherence with current best practice oral surgery guidelines. The dental profession must show leadership in slowing antibiotic resistance by pledgina to safeguard their appropriate use.

Bacterial cooperative organization under antibiotic stress

NASA Astrophysics Data System (ADS)

Ben-Jacob, Eshel; Cohen, Inon; Golding, Ido; Gutnick, David L.; Tcherpakov, Marianna; Helbing, Dirk; Ron, Ilan G.

2000-07-01

Bacteria have developed sophisticated modes of cooperative behavior to cope with unfavorable environmental conditions. Here we report the effect of antibiotic stress on the colonial development of Paenibacillus dendritiformis and P. vortex. We focus on the effect of co-trimoxazole on the colonial organization of P. dendritiformis. We find that the exposure to non-lethal concentrations of antibiotic leads to dramatic changes in the colonial growth patterns. Branching, tip-splitting patterns are affected by reduction in the colonial fractal dimension from Df=2.0 to 1.7, appearance of pronounced weak chirality and pronounced radial orientation of the growth. We combine the experimental observations with numerical studies of both discrete and continuous generic models to reveal the causes for the modifications in the patterns. We conclude that the bacteria adjust their chemotactic signaling together with variations in the bacteria length and increase in the metabolic load.

Salmonella isolated from the feces of migrating cranes at the Izumi Plain (2002-2008): serotype, antibiotic sensitivity and PFGE type.

PubMed

Kitadai, Noriyuki; Ninomiya, Naoko; Murase, Toshiyuki; Obi, Takeshi; Takase, Kozo

2010-07-01

From November 2002 to February 2008, 2,251 crane feces were collected at the Izumi Plain in Kagoshima Prefecture. Salmonella enterica was isolated from 359 feces (15.9%), of which 332 (92.5%) were Salmonella Typhimurium (ST), 9 were S. Hvittingfoss/II, 4 were S. Abaetetuba, 3 were S. Enteritidis, 2 were S. Konstanz, 1 was S. Pakistan and 8 were untyped isolates, respectively. Against 12 antimicrobial agents, no resistant strains were found in 154 isolates examined, but one was found to be resistant to ampicillin. By pulsed-field gel electrophoresis (PFGE), all but one of the 68 ST isolates tested showed indistinguishable banding patterns; one had a different pattern. The results suggest that ST strains from the same origin would spread in crane flocks during their stay at Izumi Plain every winter.

Antibiotics in frozen bone grafts can cause allergic reactions in recipient patients.

PubMed

Crnogaca, Kresimir; Bicanic, Goran; Delimar, Domagoj

2015-02-01

Antibiotic prophylaxis is a routine procedure during total hip arthroplasty (THA), and the vast majority of cadavers within the multitissue procurement receive one or more antibiotics. Upon harvesting, bone grafts are stored in the bone banks on the temperature as low as -80°C for up to 5 years. It is shown in the literature that the antibiotics remain active and viable in the bone grafts even after being exposed to extremely low temperatures in the prolonged periods. Possibility of remnant antibiotic concentrations in the bone grafts and the fact that these antibiotic remnants maintain active even after being exposed to extremely low temperatures create the environment in which the possibility for the allergic reaction in sensitive patient receiving bone graft exists. We hypothesize that harvested bone grafts containing active antibiotic substance have the potential for local and systemic allergic reaction in sensitive recipient patients thus increasing morbidity and the costs of the treatment. Allergic reactions can mimic surgical site infections as well with the consequent substantial pitfalls in the treatment. Following that, in the setting of an assumed but not confirmed surgical site infection, the immunological evaluation on antibiotics for recipients of bone grafts could be added to the standard diagnostic algorithms. In addition, bone banks should be obliged to provide information of all potential drugs that can be found in every specific bone graft to the end users. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antibiogram for Periprosthetic Infections: A Tool for Better Informed Selection of Empiric Antibiotics for Surgical Site Infections.

PubMed

Chidester, Jeremy R; Danci, Ioana; Lewis, Priya; Biskup, Nataliya; Kim, Hahns; Gupta, Subhas

2016-05-01

Periprosthetic infection after breast reconstruction is not an uncommon complication, with incidence up to 24%. These infections are often treated empirically without knowing the causative bacteria or its sensitivities to various antibiotics. Even if cultures are obtained, results may not be available for several days. A retrospective chart review of 553 patients at a single institution between January 2009 and July 2014 was performed, identifying patients who (1) underwent implant-based breast reconstruction and subsequently suffered an infection and (2) had cultures available with sensitivities. We reviewed patient demographics, implant characteristics, prophylactic intravenous antibiotics, oral antibiotic maintenance used, microbiologic details, and outcomes. The goal was to identify the most common causative bacteria, as well as their sensitivities to commonly used antibiotics, to help guide antibiotic decision-making. Of the 553 patients who underwent implant-based reconstruction, 114 (20.6%) patients suffered periprosthetic infections. Of these patients, 32 (28.1%) patients (56 reconstructions, with 33 tissue expanders and 23 implants) had cultures performed revealing 43 bacterial species, with the most common being Staphylococcus aureus (23.2%) and Pseudomonas aeruginosa (26.8%). Ceftazidime and piperacillin/tazobactam were equally effective covering 100% of Pseudomonas, enteric, and atypical organisms (P = 1), whereas vancomycin covered 100% of gram-positive organisms. Trimethoprim/sulfamethoxazole covered 100% of S. aureus, whereas clindamycin only covered 71% of S. aureus (P = 0.03). Additionally, trimethoprim/sulfamethoxazole was better able to cover atypical and enteric organisms. Ciprofloxacin covered 71% of Pseudomonas compared with 56% for levofloxacin (P = 0.14). Interestingly, cephalexin, a common choice for perioperative prophylaxis, was highly ineffective for gram-positive species in patients who later returned with infections. This study supports the efficacy of current intravenous antibiotics protocols but questions the efficacy of both clindamycin and levofloxacin in empirically treating periprosthetic infections and cephalexin in providing effective perioperative prophylaxis against skin flora. Because bacterial sensitivities vary by location and patient population, this study encourages other centers to develop their own antibiogram specifically tailored to periprosthetic infections to improve antimicrobial decision making and potentially improve implant salvage.

Tolerance in Nonhuman Primates by Delayed Mixed Chimerism

DTIC Science & Technology

2014-10-01

swelling at the surgical site was noted, associated with cellulitis tracking proximally in the recipient forearm and purulent discharge from the...antibiotic sensitivity screening and empirical antibiotic therapy started. This treatment resulted in rapid improvement, with relief of cellulitis

Phenotypic and antibiogram pattern of V. cholerae isolates from a tertiary care hospital in Mumbai during 2004-2013: a retrospective cross-sectional study.

PubMed

Torane, V; Kuyare, S; Nataraj, G; Mehta, P; Dutta, S; Sarkar, B

2016-11-25

Cholera is a major gastroenteric disease with reports on fluctuation and resistance. Hence, the objective is to determine the trend in seasonality, resistance pattern, prevalent biotypes, serotypes and phage types between 2004 and 2013 among Vibrio cholerae isolates. A retrospective cross-sectional study. A single-centre study was carried out at a tertiary care hospital in a metropolitan city (Mumbai) of a developing country (India). Records of stool specimen cultures of patients with suspected cholera from January 2004 to December 2013 were analysed. The organisms were identified as per standard protocol. Antimicrobial susceptibility testing was performed as per Clinical Laboratory Standard Institute. Biotyping, serotyping and phage typing were carried out. From the confirmed cases of cholera, demographic and laboratory details were noted. Descriptive analysis was used and the data were presented in the form of percentages. Vibrio cholerae was predominant in males and was isolated from 9.41% (439/4664) of stool specimens. Variability was found in terms of the gross appearance of stool specimens, seasonal trend and antibiotic resistance pattern. The antimicrobial susceptibility showed a waxing and waning pattern for most of the antibiotics (ampicillin, cefuroxime, chloramphenicol, tetracycline) tested, while for a few others the strains were either uniformly sensitive (gentamicin, norfloxacin) or resistant (trimethoprim-sulfamethoxazole, nalidixic acid). All isolates belonged to subgroup O1 and biotype El Tor. The most common serotype was Ogawa. The predominant phage type was T2 (old scheme) and T27 (new scheme). The predominant biotype, serotype and phage type were El Tor, Ogawa and T27 phage, respectively. The changing trends in antimicrobial resistance pattern over the years necessitate continued epidemiological and microbiological surveillance of the disease. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

In vitro comparison of the activity of various antibiotics and drugs against new Taiwan isolates and standard strains of avian mycoplasma.

PubMed

Lin, M Y

1987-01-01

Twenty-nine antibiotics or drugs were incorporated individually into mycoplasma agar to evaluate their inhibitory activity against avian mycoplasmas: 100 recent Taiwan isolates of 7 serotypes and 10 standard strains of 7 serotypes were tested. All of the standard strains were very sensitive to erythromycin, chlorotetracycline, doxycycline, minocycline, and tetracycline, but the local isolates were highly resistant to these antibiotics. The drugs or antibiotics that possessed an MIC90 of 50 micrograms/ml or less against the local isolates were tiamulin (less than 0.4 micrograms/ml), lincospectin (2.7), josamycin (2.7), lincomycin (3.0), spectinomycin (4.8), tylosin (6.0), kanamycin (6.0), chloramphenicol (6.0), gentamicin (7.5), apramycin (24.5), doxycycline (27.4), minocycline (29.0), spiramycin (30.0), colistin (44.3), leucomycin (45.0), and streptomycin (50.0). The MIC90 of the other antibiotics or drugs was greater than 50 micrograms/ml. None of the isolates or strains were sensitive to nalidixic acid, ronidazole, penicillin, ampicillin, cephalexin, carbadox, or four sulfa drugs at a concentration about 5 times the therapeutic level.

Infection after transrectal ultrasonography-guided prostate biopsy: increased relative risks after recent international travel or antibiotic use.

PubMed

Patel, Uday; Dasgupta, Prokar; Amoroso, Peter; Challacombe, Ben; Pilcher, James; Kirby, Roger

2012-06-01

Study Type - Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Septicaemia is the most frequent cause of hospitalization after transtrectal prostate biopsy; fatalities have been reported and the incidence is on the rise. This study shows that men with a history of recent international travel or antibiotic use have up to four times increased risk of septicaemia and hospitalization. When they do occur, infections are usually due to multi-resistant E coli and additional care, e.g. delay before biopsy, different antibiotic prophylaxis or transperineal biopsy, should be considered in these cases. OBJECTIVE • To study the infection rate after prostate biopsy in those who have travelled overseas or used antibiotics in the 4 weeks before biopsy. PATIENTS AND METHODS • A total of 316 men with a mean (range) age of 61 (45-85) years were studied. All had undergone transrectal ultrasonography (TRUS)-guided prostate biopsy after standard antibiotic prophylaxis. • Before their biopsy the patients were risk stratified and a history of recent international travel or antibiotic use was recorded. • Those who suffered sufficiently severe infection/sepsis so as to require hospitalization were identified at the end of the study period. • The characteristics of these patients and the types of infections were explored and the relative risk (RR) of infection after recent travel or antibiotic use was calculated. RESULTS • Of the 316 men, 16 were hospitalized with infection. • The group with (n= 16) and without (n= 300) infection were equivalent in age, prostate-specific antigen level, disease status and number of biopsy cores taken. • Either recent travel or antibiotic use were independent risk factors for infection [travel: 8/16 vs 76/300; P= 0.04; RR 2.7 and antibiotic use: 4/16 vs 20/300; P= 0.025; RR 4]. There was no significant pattern in the countries visited or the type of antibiotic used. • Culture results were positive in 10/16 men, and all cultures grew multiresistant Escherichia coli. The strains were uniformly resistant to ciprofloxacin and amoxycillin, and variably resistant to gentamicin and co-amoxiclav, but nearly all were sensitive to meropenem. • All patients made a full recovery after antibiotic and supportive treatment. CONCLUSIONS • Either recent international travel or antibiotic use are independent risk factors for severe infection after TRUS-guided prostate biopsy. • When infection does occur it should be treated aggressively as the causative agent is usually a multiresistant E. coli. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

Antibiotic prophylaxis practice patterns for cataract surgery in India - Results from an online survey.

PubMed

Kelkar, Aditya S; Chang, David F; Kelkar, Jai A; Mehta, Hetal M; Lahane, Tatyarao; Parekh, Ragini

2017-12-01

The aim of this study is to assess the current antibiotic prophylaxis practice patterns for cataract surgery in India. This was a questionnaire-based E-survey carried out at a tertiary eye care center in India. An E-mail invitation to complete an online 20 point questionnaire survey was sent to all members of the All India Ophthalmological Society with valid E-mail addresses using a digital E-mail service. Duplicate entries were prevented. Out of 1228 total respondents (8.2%) who completed the survey 38% reported using routine intracameral (IC) antibiotic prophylaxis. Another 7% place antibiotics in the irrigating solution. Of those using IC antibiotic prophylaxis, 91% adopted this practice within the past 2 years; 92% are using moxifloxacin with 56% using a commercially available moxifloxacin formulation. Those predominantly performing phacoemulsification (43% vs. 25% performing mostly manual small incision cataract surgery, P < 0.001) and more than 500 cataract surgeries annually (45% vs. 33%, P < 0.001) reported greater use of IC moxifloxacin. Self-reported endophthalmitis rates were statistically significantly greater in those not using IC antibiotics (0.045% vs. 0.036, P = 0.04). Although a majority of respondents believe that IC antibiotics are an important option (54%) and that it is important to have a commercially available solution (68%), many believe that other antibiotic prophylaxis methods are sufficient (31%). IC antibiotic prophylaxis for cataract surgery has sharply increased in India. In contrast to the West, intraocular moxifloxacin, which is commercially available in India, is preferred by the vast majority of users.

Empirical treatment of bacterial keratitis: an international survey of corneal specialists.

PubMed

Austin, Ariana; Schallhorn, Julie; Geske, Mike; Mannis, Mark; Lietman, Tom; Rose-Nussbaumer, Jennifer

2017-08-01

New antibiotic agents and changing susceptibility patterns may have changed the empirical treatment of bacterial keratitis. Our objective in this study was to survey cornea specialists' practice patterns in the initial treatment of bacterial ulcers. This study consisted of a short online survey emailed to members of the Cornea Society listserv for an international sample of cornea specialists. Data collection began July 2014 and ended October 2014. A total of 1009 surveys were emailed, and we received 140 (14%) responses. The majority of US clinicians surveyed (n=83, 80%) chose fortified antibiotics empirically, with 55% (n=57) selecting fortified vancomycin and 16% (n=17) using fluoroquinolone alone. International respondents were twice as likely to use fluoroquinolone monotherapy (31%, n=11, p=0.07) and less likely to use fortified vancomycin (33%, n=12, p=0.03). Forty-five per cent (n=46) of US respondents reported that their initial antibiotic choice covered methicillin-resistant Staphylococcus aureus , compared with 22% (n=8) of international respondents (p<0.01). Overall, respondents who were concerned about availability of antibiotics and toxicity were 20.86 (p<0.001) and 7.48 (p<0.001) times more likely to choose fluoroquinolone monotherapy, respectively. If respondents' primary considerations were broad spectrum coverage or antibiotic resistance they had 7.10 (p<0.001) and 12.51 (p<0.001) times the odds of using fortified vancomycin, respectively. Practice patterns for the initial treatment of bacterial keratitis vary with clinicians in the USA being more likely to use fortified antibiotics versus fluoroquinolone monotherapy and more concerned with resistant organisms than their international peers.

Analysis of etiology and drug resistance of biliary infections.

PubMed

Wang, Xin; Li, Qiu; Zou, Shengquan; Sun, Ziyong; Zhu, Feng

2004-01-01

The bile was collected from fro patients with biliary infections, with the bacterium isolated to study the sensitivity of each kind of the bacterium to several antibiotics in common use. Except G- bacterium, we also found some kinds of G+ bacterium in infection bile. G- bacterium were not sensitive to Clindamycin, G+ bacterium were sensitive to Ciprofloxacin. Escherichia coli, Xanthomonas maltophilia, Enterobacter cloacae, Pseudomonas aeruginosa were sensitive to Ampicillin. G+ bacterium were not sensitive to Azactam. Enterococcus faecalis, Enterococcus faecium, Enterobacter cloacae were not sensitive to Ceftazidime. Enterococcus faecalis, Staphylococcus coagulase negative, Staphylococcus epidermidis, Pseudomonas aeruginosa were not sensitive to Ceftriaxone Sodium. We didn't found any bacterium resistance Imipenem. The possibility of the existence of G+ bacterium as well as drug resistance should be considered n patients with biliary infections. The value of susceptibility test should be respected to avoid drug abuse of antibiotics.

A simple, fast and sensitive screening LC-ESI-MS/MS method for antibiotics in fish.

PubMed

Guidi, Letícia Rocha; Santos, Flávio Alves; Ribeiro, Ana Cláudia S R; Fernandes, Christian; Silva, Luiza H M; Gloria, Maria Beatriz A

2017-01-15

The objective of this study was to develop and validate a fast, sensitive and simple liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the screening of six classes of antibiotics (aminoglycosides, beta-lactams, macrolides, quinolones, sulfonamides and tetracyclines) in fish. Samples were extracted with trichloroacetic acid. LC separation was achieved on a Zorbax Eclipse XDB C18 column and gradient elution using 0.1% heptafluorobutyric acid in water and acetonitrile as mobile phase. Analysis was carried out in multiple reaction monitoring mode via electrospray interface operated in the positive ionization mode, with sulfaphenazole as internal standard. The method was suitable for routine screening purposes of 40 antibiotics, according to EC Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines, taking into consideration threshold value, cut-off factor, detection capability, limit of detection, sensitivity and specificity. Real fish samples (n=193) from aquaculture were analyzed and 15% were positive for enrofloxacin (quinolone), one of them at a higher concentration than the level of interest (50µgkg -1 ), suggesting possible contamination or illegal use of that antibiotic. Copyright © 2016 Elsevier B.V. All rights reserved.

Novel Quorum-Quenching Agents Promote Methicillin-Resistant Staphylococcus aureus (MRSA) Wound Healing and Sensitize MRSA to β-Lactam Antibiotics

PubMed Central

Kuo, David; Yu, Guanping; Hoch, Wyatt; Gabay, Dean; Long, Lisa; Ghannoum, Mahmoud; Nagy, Nancy; Harding, Clifford V.; Viswanathan, Rajesh

2014-01-01

The dwindling repertoire of antibiotics to treat methicillin-resistant Staphylococcus aureus (MRSA) calls for novel treatment options. Quorum-quenching agents offer an alternative or an adjuvant to antibiotic therapy. Three biaryl hydroxyketone compounds discovered previously (F1, F12, and F19; G. Yu, D. Kuo, M. Shoham, and R. Viswanathan, ACS Comb Sci 16:85–91, 2014) were tested for efficacy in MRSA-infected animal models. Topical therapy of compounds F1 and F12 in a MRSA murine wound infection model promotes wound healing compared to the untreated control. Compounds F1, F12, and F19 afford significant survival benefits in a MRSA insect larva model. Combination therapy of these quorum-quenching agents with cephalothin or nafcillin, antibiotics to which MRSA is resistant in monotherapy, revealed additional survival benefits. The quorum-quenching agents sensitize MRSA to the antibiotic by a synergistic mode of action that also is observed in vitro. An adjuvant of 1 μg/ml F1, F12, or F19 reduces the MIC of nafcillin and cephalothin about 50-fold to values comparable to those for vancomycin, the antibiotic often prescribed for MRSA infections. These findings suggest that it is possible to resurrect obsolete antibiotic therapies in combination with these novel quorum-quenching agents. PMID:25534736

Novel quorum-quenching agents promote methicillin-resistant Staphylococcus aureus (MRSA) wound healing and sensitize MRSA to β-lactam antibiotics.

PubMed

Kuo, David; Yu, Guanping; Hoch, Wyatt; Gabay, Dean; Long, Lisa; Ghannoum, Mahmoud; Nagy, Nancy; Harding, Clifford V; Viswanathan, Rajesh; Shoham, Menachem

2015-03-01

The dwindling repertoire of antibiotics to treat methicillin-resistant Staphylococcus aureus (MRSA) calls for novel treatment options. Quorum-quenching agents offer an alternative or an adjuvant to antibiotic therapy. Three biaryl hydroxyketone compounds discovered previously (F1, F12, and F19; G. Yu, D. Kuo, M. Shoham, and R. Viswanathan, ACS Comb Sci 16:85-91, 2014) were tested for efficacy in MRSA-infected animal models. Topical therapy of compounds F1 and F12 in a MRSA murine wound infection model promotes wound healing compared to the untreated control. Compounds F1, F12, and F19 afford significant survival benefits in a MRSA insect larva model. Combination therapy of these quorum-quenching agents with cephalothin or nafcillin, antibiotics to which MRSA is resistant in monotherapy, revealed additional survival benefits. The quorum-quenching agents sensitize MRSA to the antibiotic by a synergistic mode of action that also is observed in vitro. An adjuvant of 1 μg/ml F1, F12, or F19 reduces the MIC of nafcillin and cephalothin about 50-fold to values comparable to those for vancomycin, the antibiotic often prescribed for MRSA infections. These findings suggest that it is possible to resurrect obsolete antibiotic therapies in combination with these novel quorum-quenching agents. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Designation of pathogenic resistant bacteria in the Sparusaurata sea collected in Tunisia coastlines: Correlation with high performance liquid chromatography-tandem mass spectrometry analysis of antibiotics.

PubMed

Zouiten, Amina; Mehri, Ines; Beltifa, Asma; Ghorbel, Asma; Sire, Olivier; Van Loco, Joris; Abdenaceur, Hassen; Reyns, Tim; Ben Mansour, Hedi

2017-05-01

Vibrio is characterized by a large number of species and some of them are human pathogens causing gastro intestinal and wound infections through the ingestion or manipulation of contaminated fishes including Vibrio parahaemolyticus and Vibrio alginolyticus. In this study, we reported the phenotypic and molecular characterization of Vibrio parahaemolyticus and Vibrio alginolyticus strains isolated from wild and farm sea bream (Sparus aurata L.) along the Tunisian coast from December 2015 to April 2016. Therefore, the antibiograms indicate a difference between farmed and wild fish. Resistance against amoxicillin antibiotic appears for the bacteria isolated from wild fish, while those from aquaculture farming presented sensitivity to amoxicillin and resistance to antibiotics colistin and fusidic acid. The chloramphenicol antibiotic exhibited a high sensitivity in all isolated bacteria. In fact, traces of amoxicillin in the organs of the fish from Hergla farm were detected by UPLC-MS/MS analysis during December 2016 to April 2016. In addition, antibiotics were detected in January 2014 with high concentration of norfloxacin 2262 ng/g in fish from Hergla coast. The results obtained in this work indicated that the use and presence of antibiotics in water impacts on the occurrence of resistant bacteria and the detection of antibiotic in fish. Copyright © 2017. Published by Elsevier Ltd.

Presence of antibiotic resistance genes in a sewage treatment plant in Thibodaux, Louisiana, USA.

PubMed

Naquin, Anthony; Shrestha, Arsen; Sherpa, Mingma; Nathaniel, Rajkumar; Boopathy, Raj

2015-01-01

Increasing uses and disposals of antibiotics to the environment have increased emergence of various antibiotic resistance. One of the sources for the spread of antibiotic resistance is wastewater treatment plant, where bacteria and antibiotics can come in contact and can acquire antibiotics resistance. There are very few studies on this subject from a small town sewage treatment plant. Therefore, this study was conducted using raw sewage as well as treated sewage from a sewage treatment plant in Thibodaux in rural southeast Louisiana in USA. Samples were collected monthly from the Thibodaux sewage treatment plant and the presence of antibiotic resistance genes was monitored. The study showed the presence of antibiotic resistance genes in both raw and treated sewage in every month of the study period. The genetic transformation assay showed the successful transformation of methicillin resistant gene, mecA to an antibiotic sensitive Staphylococcus aureus, which became antibiotic resistant within 24h. Copyright © 2015 Elsevier Ltd. All rights reserved.

Classification of bacterial samples as negative or positive for a UTI and antibiogram using surface enhanced Raman spectroscopy

NASA Astrophysics Data System (ADS)

Kastanos, Evdokia; Hadjigeorgiou, Katerina; Kyriakides, Alexandros; Pitris, Costas

2011-03-01

Urinary tract infection (UTI) diagnosis requires an overnight culture to identify a sample as positive or negative for a UTI. Additional cultures are required to identify the pathogen responsible for the infection and to test its sensitivity to antibiotics. A rise in ineffective treatments, chronic infections, rising health care costs and antibiotic resistance are some of the consequences of this prolonged waiting period of UTI diagnosis. In this work, Surface Enhanced Raman Spectroscopy (SERS) is used for classifying bacterial samples as positive or negative for UTI. SERS spectra of serial dilutions of E.coli bacteria, isolated from a urine culture, were classified as positive (105-108 cells/ml) or negative (103-104 cells/ml) for UTI after mixing samples with gold nanoparticles. A leave-one-out cross validation was performed using the first two principal components resulting in the correct classification of 82% of all samples. Sensitivity of classification was 88% and specificity was 67%. Antibiotic sensitivity testing was also done using SERS spectra of various species of gram negative bacteria collected 4 hours after exposure to antibiotics. Spectral analysis revealed clear separation between the spectra of samples exposed to ciprofloxacin (sensitive) and amoxicillin (resistant). This study can become the basis for identifying urine samples as positive or negative for a UTI and determining their antibiogram without requiring an overnight culture.

[Epidemiologic diagnostic of nosocomial suppurative-septic infections of Pseudomonas etiology based on intraspecies typing of causative agent].

PubMed

Fel'dblium, I V; Zakharova, Iu A; Nikolaeva, A M; Fedotova, O S

2013-01-01

Scientific justification of optimization of epidemiologic diagnostic of suppurative-septic infection (SSI) caused by Pseudomonas aeruginosa based on comparability of antibiotic sensitivity and beta-lactamase production. Intraspecies typing of 37 P. aeruginosa strains isolated during microbiological monitoring of 106 patients and 131 objects of clinical environment of surgical and obstetrician hospitals by using a complex ofphenotypic and molecular-biological methods including determination of sensitivity to antibiotics by serial dilutions method and PCR-diagnostics with determination of TEM, SHV, CTX, OXA, MBL, VIM genes was performed. P. aeruginosa strains combined into groups by isolation location during studies turned out to be heterogeneous by sensitivity to antibiotics and beta-lactamase production that allowed to form subgroups of strains by focality attribute. Isolates recovered from different SSI foci had significant differences in minimal inhibitory concentration (MIC) reaching 1024 times. MIC parameter within subgroups did not exceed 8 - 16 consequent dilutions. Use of a complex of phenotypic and molecular-biologic methods of causative agent typing including determination of sensitivity to antibiotics by serial dilutions method and evaluation of beta-lactamase production allowed to establish a mechanism of development of SSI epidemic process caused by P. aeruginosa, detect origins and reservoirs of infection in hospital, modes and factors of transmission and reach maximum justification of epidemiologic control and prophylaxis measures of localization of foci of nosocomial infections of pseudomonas etiology.

Whole genome and transcriptome analyses of environmental antibiotic sensitive and multi-resistant Pseudomonas aeruginosa isolates exposed to waste water and tap water.

PubMed

Schwartz, Thomas; Armant, Olivier; Bretschneider, Nancy; Hahn, Alexander; Kirchen, Silke; Seifert, Martin; Dötsch, Andreas

2015-01-01

The fitness of sensitive and resistant Pseudomonas aeruginosa in different aquatic environments depends on genetic capacities and transcriptional regulation. Therefore, an antibiotic-sensitive isolate PA30 and a multi-resistant isolate PA49 originating from waste waters were compared via whole genome and transcriptome Illumina sequencing after exposure to municipal waste water and tap water. A number of different genomic islands (e.g. PAGIs, PAPIs) were identified in the two environmental isolates beside the highly conserved core genome. Exposure to tap water and waste water exhibited similar transcriptional impacts on several gene clusters (antibiotic and metal resistance, genetic mobile elements, efflux pumps) in both environmental P. aeruginosa isolates. The MexCD-OprJ efflux pump was overexpressed in PA49 in response to waste water. The expression of resistance genes, genetic mobile elements in PA49 was independent from the water matrix. Consistently, the antibiotic sensitive strain PA30 did not show any difference in expression of the intrinsic resistance determinants and genetic mobile elements. Thus, the exposure of both isolates to polluted waste water and oligotrophic tap water resulted in similar expression profiles of mentioned genes. However, changes in environmental milieus resulted in rather unspecific transcriptional responses than selected and stimuli-specific gene regulation. © 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Antibiotic resistance and molecular characterization of diarrheagenic Escherichia coli and non-typhoidal Salmonella strains isolated from infections in Southwest China.

PubMed

Zhang, Shun-Xian; Zhou, Yong-Ming; Tian, Li-Guang; Chen, Jia-Xu; Tinoco-Torres, Rita; Serrano, Emmanuel; Li, Shi-Zhu; Chen, Shao-Hong; Ai, Lin; Chen, Jun-Hu; Xia, Shang; Lu, Yan; Lv, Shan; Teng, Xue-Jiao; Xu, Wen; Gu, Wen-Peng; Gong, Si-Tang; Zhou, Xiao-Nong; Geng, Lan-Lan; Hu, Wei

2018-05-07

Bacterial diarrhea is one of the most common causes for medical consultations, mortality and morbidity in the world. Diarrheagenic Escherichia coli (DEC) and non-typhoidal Salmonella (NTS) are major intestinal pathogens in developing countries, and the indiscriminate use of antibiotics has greatly contributed to resistant strains. Hence, the aim of the present study is to identify the antimicrobial resistance patterns and the molecular characteristics of DEC and NTS in southwest, China. 1121 diarrheal patients and 319 non-diarrheal subjects across all age groups were recruited from four sentinel hospitals from June 2014 to July 2015 in Kunming City, Yunnan Province. Each stool specimen was collected to detect DEC and NTS with standard microbiological and molecular methods. Antimicrobial resistance testing was performed with the Kirby-Bauer disk diffusion method, and the standards for antimicrobial susceptibility testing complied with the Clinical and Laboratory Standards Institute (CLSI). Molecular characterization of strains was carried out using pulsed-field gel electrophoresis (PFGE). A structured questionnaire was used to record basic epidemiological data (e.g. sex, age, residence, season, etc.). Data were analyzed using Chi-square or Fisher's exact test. DEC was detected in 127 (11.33%) diarrhea cases and 9 (2.82%) non-diarrheal cases (χ 2  = 20.69, P < 0.001, OR = 4.36, 95% CI: 2.19-8.65), and the prevalence of NTS isolated from diarrhea cases was higher than that of non-diarrheal cases across all age groups (n = 42, 3.75%, n = 1, 0.31%, χ 2  = 10.10, P = 0.002, OR = 12.38, 95% CI: 1.70-90.29). The rates of resistance to ten antibiotics of DEC and NTS showed significant differences (χ 2  = 386.77, P < 0.001; χ 2  = 191.16, P < 0.001). The rates of resistance to Amoxicillin and Clavulafiate (AMC), Cephalothin (CEP), Gentamicin (GEN) and Sulfamethoxazole-Trimethoprim (SXT) of DEC isolated from diarrhea cases were higher than those of NTS isolated from diarrhea patients (37.01% vs 14.29%, χ 2  = 7.57, P = 0.006; 29.92% vs 11.90%, χ 2  = 5.40, P = 0.02; 37.01% vs 11.90%, χ 2  = 5.80, P = 0.016; 62.20% vs 26.19%, χ 2  = 16.44, P < 0.001; respectively). Ciprofloxacin (CIP) was the most sensitive antibiotic for DEC and NTS strains isolated from diarrhea cases. Resistance rates of DEC isolates from cases and controls to more than three kinds antimicrobials (multidrug resistance, MDR) showed no significant differences (81.10% vs 88.89%, P = 0.33). Pulsotype patterns of DEC strains were highly diverse; however, the pulsotype pattern of NTS strains was closely related to the serotype. The pattern of S. enteritidis was highly similar, but the S. enterica Typhimurium strain was discrete. Antibiotic resistance of Enterobacteriaceae is of great concern. The societal effects of antibiotic use justify strict monitoring to combat increases in antimicrobial resistance. Molecular epidemiology and systematic epidemiological investigation can provide accurate evidence for tracking the infection source.

What should be the antibiotic prescription protocol for burn patients admitted in the department of burns, plastic and reconstructive surgery.

PubMed

Mir, Mohd Altaf; Khurram, Mohammad Fahud; Khan, Arshad Hafiz

2017-02-01

This is a prospective study with the aim to determine specific patterns of burn wound bacterial colonisation and antimicrobial resistance profiles. There is a high incidence of infections and septicaemia in post-burn patients, which, in turn, are associated with high morbidity and mortality, a fact that compelled us to undertake this study. The study was conducted over a period 11 months, from 1 August 2014 to 30 June 2015, in 50 burn patients admitted in our burn unit. Wound cultures were taken after 72 hours of admission from all the patients, and then, empirical systemic antibiotics were administered. For wound cultures; 1 cubic cm tissue was taken and placed in aerobic and anaerobic culture vials and transported to the microbiology lab under all aseptic precautions as soon as possible. At the time of fever any time after 72 hours of admission, 16 ml of blood was drawn under all aseptic precautions. Both aerobic and anaerobic blood culture vials were filled with 8 ml of blood each and transported to the microbiology lab. The results of culture and sensitivity reports of 50 patients were recorded. The data obtained was analysed using appropriate statistical analytical tests. The most common organism responsible for bacteraemia is Pseudomonas (43%). Most of the strains of organisms isolated were resistant to commonly used antibiotics in the hospital; Pseudomonas was found 100% resistant to a combination of ampicillin + sulbactum, ceftriaxone and was most often sensitive to imipenem, amikacin and vancomycin. Methicillin-resistant Staphylococcus aureus (MRSA) was also found resistant to commonly used antibiotics like ceftriaxone, ampicillin + sulbactum and ceftazidime + calvulanic acid. Linzolid and vancomycin were effective in 83% and 100% cases, respectively. We conclude that similar institution-specific studies should be conducted, and such studies will be helpful in providing useful guidelines for choosing effective empirical therapy that will have a great impact on the prevention of infection and its complications in burn patients because of bacteraemia. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Epidemiology of antibiotic and heavy metal resistance in bacteria: resistance patterns in staphylococci isolated from populations in Iraq exposed and not exposed to heavy metals or antibiotics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Groves, D.J.; Short, H.; Thewaini, A.J.

Staphylococci were isolated from rural and urban populations in Iraq, which were not known to be exposed to either heavy metals or antibiotics. The antibiotic and heavy metal resistance patterns of these strains were analyzed in both mannitol-fermenting and nonfermenting strains. Over 90% of the strains were resistant to at least one of the following antibiotics: penicillin, chloramphenicol, erythromycin, tetracycline, cephalothin, lincomycin, and methicillin. In general, mannitol-fermenting strains were resistant to penicillin and cupric ions. Mannitol-negative strains were more frequently associated with mercuric ion and tetracycline resistance. Although resistance to penicillin and tetracycline can coexist, the combination of penicillin resistancemore » and tetracycline resistance usually occurred in mannitol-negative strains. The possibility of selection of heavy metal-resistant strains due to exposure to toxic levels of methylmercury was examined. No significant increase in mercuric ion-resistant strains of staphylococci or Escherichia coli were detected in exposed populations as compared to control groups. The possible reasons for this result are discussed.« less

Determination of antibiotic consumption index for animal originated foods produced in animal husbandry in Iran, 2010

PubMed Central

2014-01-01

The public health concerns over the long-term exposure to antibiotics have risen in different parts of the world. The purpose of this study was to investigate the antibiotic consumption pattern in livestock and poultry and to estimate the quantity of antibiotic active ingredient (mg) consumed per unit weight (Kg) of red meat, milk and egg production in Iran in 2010. A cross-sectional study was designed in charmahal - bakhtiary province-Iran. A questioner has been developed by naming 110 types of antibiotics. Twenty two veterinary clinicians and three livestock pharmaceutical distributor companies were included in the survey to determine the antibiotic prescription and distribution pattern in the farms. Veterinary organization of Iran supplied the information of the total antibiotic consumption in different dosage forms. National and international data on the livestock and poultry production were obtained from the relevant official web sites. Tetracycline class of antibiotics was the most common types of antibacterial prescribed and sold to both livestock and poultry farms. Amino glycoside, penicillin and macrolide in the cattle farms and furofenocole in broiler farms were the second most used groups of antibiotics. The quantity of antibiotic active ingredients consumed per unit weight of animal-originated food products was counted as 107.4 mg/kg for both milk and red meat and 249.5 mg/kg for broiler meat and egg. Totally, it was estimated that 133 mg antibiotic substances was used per kg of milk, meat and egg produced in 2010. In comparison to available data for other countries, consumption of antibiotics in livestock and poultry in Iran is higher than developed countries with an exception of South Korea. The findings of the present study could be alarming for the legislative authorities in food security and safety. More clear evaluation should be carried out as well as implementation of national monitoring and inspective programs in order to reach an added safety regarding animal-originated foods. PMID:24468281

Determination of antibiotic consumption index for animal originated foods produced in animal husbandry in Iran, 2010.

PubMed

Aalipour, Fathollah; Mirlohi, Maryam; Jalali, Mohammd

2014-01-27

The public health concerns over the long-term exposure to antibiotics have risen in different parts of the world. The purpose of this study was to investigate the antibiotic consumption pattern in livestock and poultry and to estimate the quantity of antibiotic active ingredient (mg) consumed per unit weight (Kg) of red meat, milk and egg production in Iran in 2010. A cross-sectional study was designed in charmahal - bakhtiary province-Iran. A questioner has been developed by naming 110 types of antibiotics. Twenty two veterinary clinicians and three livestock pharmaceutical distributor companies were included in the survey to determine the antibiotic prescription and distribution pattern in the farms. Veterinary organization of Iran supplied the information of the total antibiotic consumption in different dosage forms. National and international data on the livestock and poultry production were obtained from the relevant official web sites. Tetracycline class of antibiotics was the most common types of antibacterial prescribed and sold to both livestock and poultry farms. Amino glycoside, penicillin and macrolide in the cattle farms and furofenocole in broiler farms were the second most used groups of antibiotics. The quantity of antibiotic active ingredients consumed per unit weight of animal-originated food products was counted as 107.4 mg/kg for both milk and red meat and 249.5 mg/kg for broiler meat and egg. Totally, it was estimated that 133 mg antibiotic substances was used per kg of milk, meat and egg produced in 2010. In comparison to available data for other countries, consumption of antibiotics in livestock and poultry in Iran is higher than developed countries with an exception of South Korea. The findings of the present study could be alarming for the legislative authorities in food security and safety. More clear evaluation should be carried out as well as implementation of national monitoring and inspective programs in order to reach an added safety regarding animal-originated foods.

Characterization of the components of meleumycin by liquid chromatography with photo-diode array detection and electrospray ionization tandem mass spectrometry.

PubMed

Wang, Ming-Juan; Li, Ya-Ping; Wang, Yan; Li, Jin; Hu, Chang-Qin; Hoogmartens, Jos; Van Schepdael, Ann; Adams, Erwin

2013-10-01

Reversed-phase liquid chromatography coupled with photo-diode array (PDA) detection and electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to characterize the components of meleumycin, a 16-membered macrolide antibiotic produced by fermentation. In total 31 components were characterized in commercial samples, including 12 impurities that had never been reported before and 12 others that were partially characterized. The structures of these unknown compounds were deduced by comparison of their fragmentation patterns with those of known components. Their ultraviolet spectra and chromatographic behavior were used to confirm the proposed structures: e.g. λmax shift from 232 nm to 282 nm would indicate the presence of an α-, β-, γ-, δ-unsaturated ketone instead of a normal α-, β-, γ-, δ-unsaturated alcohol in the 16-membered ring of the examined components. Compared to other methods, this LC/MS(n) method is particularly advantageous to characterize minor components at trace levels in multi-components antibiotics, in terms of sensitivity and efficiency. Copyright © 2013 Elsevier B.V. All rights reserved.

Choosing the correct empirical antibiotic for urinary tract infection in pediatric: Surveillance of antimicrobial susceptibility pattern of Escherichia coli by E-Test method.

PubMed

Sedighi, Iraj; Solgi, Abbas; Amanati, Ali; Alikhani, Mohammad Yousef

2014-12-01

Urinary Tract Infections (UTIs) are of the most common bacterial diseases worldwide. We investigate the antibiotic susceptibility patterns of Escherichia coli (E. coli) strains isolated from pediatric patients with community acquired urinary tract infection (UTI) to find a clinical guidance for choosing a right empirical antibiotic in these patients. In this cross sectional study, 100 urine specimens which were positive for E. coli had been investigated for antibiotics susceptibility pattern. The susceptibility to Co-trimoxazol (25μg), Amikacin (30μg), Ceftriaxone (30μg), Nalidixic Acid (30μg), Cefixime (5μg), and Nitrofurantoin (300μg) tested with Disk diffusion agar and MIC determined with the E-test. Mean age of patients was 38 Months. Girls had greater proportion than boys (74 versus 26%). In Disk diffusion method, 26% of the isolates were susceptible to cotrimoxazole. Susceptibility to amikacin, ceftriaxone, nitrofurantoin, nalidixic acid and cefixime was 94%, 66%, 97%, 62% and 52%, respectively. By E-Test method and according to CLSI criteria susceptibility for co-trimoxazol, amikacin, ceftriaxone and nalidixic acid was 37%, 97%, 67% and 50%, respectively. The highest percentage of agreement between Disk diffusion and E-Test method was found for amikacin (96%) and the lowest percentage for co-trimoxazole (89%). Treatment failure, prolonged or repeated hospitalization, increased costs of care, and increased mortality are some consequence of bacterial resistance in UTIs. Misuse of antibiotics in each geographic location directly affects antibiotic resistance pattern. In the treatment of UTI, proper selection of antimicrobial agents should be relevant to the bacterial susceptibility testing surveillance. According to our results, amikacin as an injectable drug and nitrofurantoin as an oral agent could be used as a drug of choice in our region for children with UTIs.

The model of fungal population dynamics affected by nystatin

NASA Astrophysics Data System (ADS)

Voychuk, Sergei I.; Gromozova, Elena N.; Sadovskiy, Mikhail G.

Fungal diseases are acute problems of the up-to-day medicine. Significant increase of resistance of microorganisms to the medically used antibiotics and a lack of new effective drugs follows in a growth of dosage of existing chemicals to solve the problem. Quite often such approach results in side effects on humans. Detailed study of fungi-antibiotic dynamics can identify new mechanisms and bring new ideas to overcome the microbial resistance with a lower dosage of antibiotics. In this study, the dynamics of the microbial population under antibiotic treatment was investigated. The effects of nystatin on the population of Saccharomyces cerevisiae yeasts were used as a model system. Nystatin effects were investigated both in liquid and solid media by viability tests. Dependence of nystatin action on osmotic gradient was evaluated in NaCl solutions. Influences of glucose and yeast extract were additionally analyzed. A "stepwise" pattern of the cell death caused by nystatin was the most intriguing. This pattern manifested in periodical changes of the stages of cell death against stages of resistance to the antibiotic. The mathematical model was proposed to describe cell-antibiotic interactions and nystatin viability effects in the liquid medium. The model implies that antibiotic ability to cause a cells death is significantly affected by the intracellular compounds, which came out of cells after their osmotic barriers were damaged

A historical legacy of antibiotic utilization on bacterial seed banks in sediments

PubMed Central

Junier, Thomas; Bayrychenko, Zhanna; Filippidou, Sevasti; Beck, Karin; Greub, Gilbert; Bürgmann, Helmut

2018-01-01

The introduction of antibiotics for both medical and non-medical purposes has had a positive effect on human welfare and agricultural output in the past century. However, there is also an important ecological legacy regarding the use of antibiotics and the consequences of increased levels of these compounds in the environment as a consequence of their use and disposal. This legacy was investigated by quantifying two antibiotic resistance genes (ARG) conferring resistance to tetracycline (tet(W)) and sulfonamide (sul1) in bacterial seed bank DNA in sediments. The industrial introduction of antibiotics caused an abrupt increase in the total abundance of tet(W) and a steady increase in sul1. The abrupt change in tet(W) corresponded to an increase in relative abundance from ca. 1960 that peaked around 1976. This pattern of accumulation was highly correlated with the abundance of specific members of the seed bank community belonging to the phylum Firmicutes. In contrast, the relative abundance of sul1 increased after 1976. This correlated with a taxonomically broad spectrum of bacteria, reflecting sul1 dissemination through horizontal gene transfer. The accumulation patterns of both ARGs correspond broadly to the temporal scale of medical antibiotic use. Our results show that the bacterial seed bank can be used to look back at the historical usage of antibiotics and resistance prevalence. PMID:29312823

Use of AFLP, plasmid typing and phenotyping in a comparative study to assess genetic diversity of Shigella flexneri strains.

PubMed Central

Herrera, S.; Cabrera, R.; Ramirez, M. M.; Usera, M. A.; Echeita, M. A.

2002-01-01

Shigella flexneri infections are one of the main causes of acute diarrhoea in Cuba. Twenty strains isolated from sporadic cases in nine different Cuban provinces were characterized. Serotyping, antibiotic-resistance typing, plasmid-typing and AFLP-typing were used to determine their suitability for use in epidemiological studies of S. flexneri. The predominant serotypes were serotype 6 (35%) and serotype 2 (35%). Eleven different plasmid profiles were detected (Diversity Index = 0.92). AFLP-typing discriminated 12 different patterns (DI = 0.95), these patterns were not coincident with plasmid-typing patterns. Both techniques combined distinguished 14 patterns among the 20 studied strains (DI = 0.99). There was no consistent relationship between plasmid-typing and AFLP-typing patterns or antibiotic-resistance typing patterns. Ninety-five percent of S. flexneri strains were multiresistant. PMID:12558326

Resistance pattern of breakthrough urinary tract infections in children on antibiotic prophylaxis.

PubMed

Nateghian, Ali Reza; Robinson, Joan L; Mohandessi, Shahab; Hooman, Nakysa

2009-01-01

Prophylactic antibiotics are commonly used for prevention of urinary tract infections (UTIs) in children. It was postulated that the organisms and resistance patterns of breakthrough infections would differ with the choice of antimicrobial prophylaxis. This was a retrospective descriptive study of all breakthroughs UTI from 2000 to 2006 in children over 1 month of age discharged from a referral children's hospital in Tehran, Iran on continuous antibiotic prophylaxis for UTIs. Fifty-seven children discharged on prophylaxis had breakthrough UTIs of which 32 (56%) had a previously diagnosed urinary tract anomaly. Escherichia coli was responsible for the majority of infections irrespective of choice of prophylaxis. Thirty-three of 56 breakthrough UTIs (59%) were with organisms that were resistant to the prophylactic antibiotic. There was an increased incidence of resistance to prophylaxis in children on cefixime (16 of 22; 78%) when compared with children on cephalexin (7 of 19; 37%; p=0.02) and a trend toward increased resistance when compared with children on trimethoprim-sulfamethoxasole (3 of 8; 37%) (p=0.10). In conclusion, the resistance pattern of organisms causing breakthrough UTIs varies with the choice of prophylaxis which should be taken into consideration in chosing empiric therapy for such infections.

Management of Respiratory Infections with Use of Procalcitonin: Moving toward More Personalized Antibiotic Treatment Decisions.

PubMed

Wirz, Yannick; Branche, Angela; Wolff, Michel; Welte, Tobias; Nobre, Vandack; Reinhart, Konrad; Falsey, Ann R; Damas, Pierre; Beishuizen, Albertus; Deliberato, Rodrigo O; Shehabi, Yahya; Jensen, Jens-Ulrik S; Mueller, Beat; Schuetz, Philipp

2017-12-08

Due to overlap of clinical findings and low sensitivity of bacterial diagnostic tests, differentiation between bacterial and viral respiratory tract infections remains challenging, ultimately leading to antibiotic overuse in this population of patients. Addition of procalcitonin, a blood biomarker expressed by epithelial cells in response to bacterial infections, to the clinical assessment leads to a reduction in inappropriate antibiotic initiation. Procalcitonin also provides prognostic information about the resolution of illness, and significant decreases over time are a strong signal for the discontinuation of antibiotics. Current evidence from randomized trials indicates that procalcitonin-guided antibiotic stewardship results in a reduction in antibiotic use and antibiotic side effects, which importantly translates into improved survival of patients with respiratory infections. Inclusion of procalcitonin into antibiotic stewardship algorithms thus improves the diagnostic and therapeutic management of patients presenting with respiratory illnesses and holds great promise to mitigate the global bacterial resistance crisis.

Coexistence of antibiotic-producing and antibiotic-sensitive bacteria in biofilms is mediated by resistant bacteria.

PubMed

Narisawa, Naoki; Haruta, Shin; Arai, Hiroyuki; Ishii, Masaharu; Igarashi, Yasuo

2008-06-01

Antibiotic-sensitive bacteria have been found to coexist with antibiotic-producing bacteria in biofilms, but little is known about how the former develop in such an environment. Here we isolated pyocyanin-sensitive bacteria belonging to the genus Brevibacillus from a biofilm derived from soil extract and based on the preestablished biofilm of a pyocyanin producer, Pseudomonas aeruginosa strain P1. In addition, pyocyanin-resistant strains belonging to the genus Raoultella were isolated from the same biofilm. Microbial relationships within biofilms were examined by using three strains, strain P1, Brevibacillus strain S1, and Raoultella strain R1, each of which individually formed a biofilm within 2 days in a flow cell. Strain S1 did not fully develop on the preestablished biofilm of strain P1 during 4 days of cultivation, whereas a mutant of strain P1 which was deficient in pyocyanin production allowed strain S1 to cocolonize within a biofilm. On the other hand, strain R1 developed on the biofilm of strain P1 regardless of pyocyanin production. When mixed 1:1 inocula of strains S1 and R1 were introduced into the strain P1 biofilm, all three species were found in the 4-day biofilm. In the mixed biofilm, strain S1 was surrounded by the layer of strain R1 and seemed to be separated from strain P1 and the outflow solution. However, strain S1 did not survive in a three-species mixed culture under planktonic conditions. These results indicate that the survival of sensitive bacteria in biofilm with a pyocyanin producer is achieved by covering them with a layer of resistant bacteria. We also evaluated the influence of antibiotic production on the producer.

["Antibiotic hierarchy" oriented antibacterial chemotherapy in urinary tract infections].

PubMed

Walther, H; Meyer, F P; Kiessig, R; Müller, G W

1982-12-01

The resistance of 708 germs isolated from 656 samples of ambulatory urological and gynecological origin was determined. The sensitivity of E. coli, proteus types and Pseudomonas aeruginosa to internationally used antibiotics was registered in detail as percentages. On the basis of the frequency of the germs and their resistence, an antibiotic "hierarchy" is drawn up, which can simplify the initial choice of therapy, especially in out-patient treatment.

Incremental cost of nosocomial bacteremia according to the focus of infection and antibiotic sensitivity of the causative microorganism in a university hospital.

PubMed

Riu, Marta; Chiarello, Pietro; Terradas, Roser; Sala, Maria; Garcia-Alzorriz, Enric; Castells, Xavier; Grau, Santiago; Cots, Francesc

2017-04-01

To estimate the incremental cost of nosocomial bacteremia according to the causative focus and classified by the antibiotic sensitivity of the microorganism.Patients admitted to Hospital del Mar in Barcelona from 2005 to 2012 were included. We analyzed the total hospital costs of patients with nosocomial bacteremia caused by microorganisms with a high prevalence and, often, with multidrug-resistance. A control group was defined by selecting patients without bacteremia in the same diagnosis-related group.Our hospital has a cost accounting system (full-costing) that uses activity-based criteria to estimate per-patient costs. A logistic regression was fitted to estimate the probability of developing bacteremia (propensity score) and was used for propensity-score matching adjustment. This propensity score was included in an econometric model to adjust the incremental cost of patients with bacteremia with differentiation of the causative focus and antibiotic sensitivity.The mean incremental cost was estimated at &OV0556;15,526. The lowest incremental cost corresponded to bacteremia caused by multidrug-sensitive urinary infection (&OV0556;6786) and the highest to primary or unknown sources of bacteremia caused by multidrug-resistant microorganisms (&OV0556;29,186).This is one of the first analyses to include all episodes of bacteremia produced during hospital stays in a single study. The study included accurate information about the focus and antibiotic sensitivity of the causative organism and actual hospital costs. It provides information that could be useful to improve, establish, and prioritize prevention strategies for nosocomial infections.

Effects of temperature, genetic variation and species competition on the sensitivity of algae populations to the antibiotic enrofloxacin.

PubMed

Rico, Andreu; Zhao, Wenkai; Gillissen, Frits; Lürling, Miquel; Van den Brink, Paul J

2018-02-01

Primary producers are amongst the most sensitive organisms to antibiotic pollution in aquatic ecosystems. To date, there is little information on how different environmental conditions may affect their sensitivity to antibiotics. In this study we assessed how temperature, genetic variation and species competition may affect the sensitivity of the cyanobacterium Microcystis aeruginosa and the green-algae Scenedesmus obliquus to the antibiotic enrofloxacin. First, we performed single-species tests to assess the toxicity of enrofloxacin under different temperature conditions (20°C and 30°C) and to assess the sensitivity of different species strains using a standard temperature (20°C). Next, we investigated how enrofloxacin contamination may affect the competition between M. aeruginosa and S. obliquus. A competition experiment was performed following a full factorial design with different competition treatments, defined as density ratios (i.e. initial bio-volume of 25/75%, 10/90% and 1/99% of S. obliquus/M. aeruginosa, respectively), one 100% S. obliquus treatment and one 100% M. aeruginosa treatment, and four different enrofloxacin concentrations (i.e. control, 0.01, 0.05 and 0.10mg/L). Growth inhibition based on cell number, bio-volume, chlorophyll-a concentration as well as photosynthetic activity were used as evaluation endpoints in the single-species tests, while growth inhibition based on measured chlorophyll-a was primarily used in the competition experiment. M. aeruginosa photosynthetic activity was found to be the most sensitive endpoint to enrofloxacin (EC50-72h =0.02mg/L), followed by growth inhibition based on cell number. S. obliquus was found to be slightly more sensitive at 20°C than at 30°C (EC50-72h cell number growth inhibition of 38 and 41mg/L, respectively), whereas an opposite trend was observed for M. aeruginosa (0.047 and 0.037mg/L, respectively). Differences in EC50-72h values between algal strains of the same species were within a factor of two. The competition experiment showed that M. aeruginosa growth can be significantly reduced in the presence of S. obliquus at a density ratio of 75/25% M. aeruginosa/S. obliquus, showing a higher susceptibility to enrofloxacin than in the single-species test. The results of this study confirm the high sensitivity of cyanobacteria to antibiotics and show that temperature and inter-strain genetic variation may have a limited influence on their response to them. The results of the competition experiment suggest that the structure of primary producer communities can be affected, at least temporarily, at antibiotic concentrations close to those that have been measured in the environment. Copyright © 2017 Elsevier Inc. All rights reserved.

An occurrence of salmonella infection in cranes at the Izumi Plains, Japan.

PubMed

Maeda, Y; Tohya, Y; Nakagami, Y; Yamashita, M; Sugimura, T

2001-08-01

Ten thousand or more cranes migrate from Siberia and stay at the Izumi Plains, in the northern part of Kagoshima prefecture, Japan, every winter season. Four hundred and twenty samples of cranes feces were obtained 1995 to 1997 and investigated for Salmonella. As a result, twenty-nine of Salmonella strains were isolated. All isolates were determined to be identical, Salmonella Typhimurium (04:i: 1,2). since all of them indicated the same patterns of plasmid profiling and antibiotic sensitive spectrums. The isolates showed a high pathogenicity to chicken, and most of them were isolated in the latter half of the winter season; therefore the cranes were infected with the isolates during the winter season.

Insights in Nanoparticle-Bacterium Interactions: New Frontiers to Bypass Bacterial Resistance to Antibiotics.

PubMed

Diab, Roudayna; Khameneh, Bahman; Joubert, Olivier; Duval, Raphael

2015-01-01

Nanotechnology has been revealed as a fundamental approach for antibiotics delivery. In this paper, recent findings demonstrating the superiority of nanocarried-antibiotics over "naked" ones and the ways by which nanoparticles can help to overwhelm bacterial drug resistance are reviewed. The second part of this paper sheds light on nanoparticle-bacterium interaction patterns. Finally, key factors affecting the effectiveness of nanoparticles interactions with bacteria are discussed.

Mixed-infection of antibiotic susceptible and resistant Helicobacter pylori isolates in a single patient and underestimation of antimicrobial susceptibility testing.

PubMed

Kim, Jae J; Kim, Jong G; Kwon, Dong H

2003-06-01

Antibiotic resistance among Helicobacter pylori has been increasing worldwide and has begun to affect the overall efficacy of current antibiotic regimens adversely. We examined 220 pairs of H. pylori isolates obtained from both the antrum and corpus of separate patients; 109 (50%) harbored antibiotic-resistant H. pylori: amoxicillin (0.5%), clarithromycin (5.9%), furazolidone (1.4%), metronidazole (45.5%), nitrofurantoin (1.4%), and tetracycline (6.8%). Heteroresistance among the two biopsy sites from each patient was present in 41 of the 109 patients (38%) with antibiotic resistant H. pylori (e.g. 34% with resistant strains would be misclassified as susceptible if a biopsy of the antrum alone used for antimicrobial susceptibility testing). DNA fingerprinting genotype analysis was carried out on the 41 pairs of isolates with heteroresistance. While different patients had different fingerprinting patterns, each pair of isolates showed identical or similar fingerprinting patterns. These results suggest that antibiotic-resistant H. pylori typically develop from pre-existing susceptible strain rather than coinfection with a different strain. The minor differences in genotype (degeneration of genotype) seen reflect one of the processes for development of genetic diversity in H. pylori. No biopsy single site can be considered representative for antimicrobial susceptibility testing.

Self-Medication with Antibiotics, Attitude and Knowledge of Antibiotic Resistance among Community Residents and Undergraduate Students in Northwest Nigeria.

PubMed

Ajibola, Olumide; Omisakin, Olusola Akintoye; Eze, Anthonius Anayochukwu; Omoleke, Semeeh Akinwale

2018-04-27

This study set out to evaluate self-medicated antibiotics and knowledge of antibiotic resistance among undergraduate students and community members in northern Nigeria. Antibiotic consumption pattern, source of prescription, illnesses commonly treated, attitude towards antibiotics, and knowledge of antibiotic resistance were explored using a structured questionnaire. Responses were analyzed and summarized using descriptive statistics. Of the 1230 respondents from undergraduate students and community members, prescription of antibiotics by a physician was 33% and 57%, respectively, amongst undergraduate students and community members. We tested the respondents’ knowledge of antibiotic resistance (ABR) and found that undergraduate students displayed less knowledge that self-medication could lead to ABR (32.6% and 42.2% respectively). Self-medication with antibiotics is highly prevalent in Northwest Nigeria, with most medicines being purchased from un-licensed stores without prescription from a physician. We also observed a significant gap in respondents’ knowledge of ABR. There is an urgent need for public health authorities in Nigeria to enforce existing laws on antibiotics sales and enlighten the people on the dangers of ABR.

The role of point-of-care tests in antibiotic stewardship for urinary tract infections in a resource-limited setting on the Thailand-Myanmar border.

PubMed

Chalmers, Lauren; Cross, Jessica; Chu, Cindy S; Phyo, Aung Pyae; Trip, Margreet; Ling, Clare; Carrara, Verena; Watthanaworawit, Wanitda; Keereecharoen, Lily; Hanboonkunupakarn, Borimas; Nosten, François; McGready, Rose

2015-10-01

Published literature from resource-limited settings is infrequent, although urinary tract infections (UTI) are a common cause of outpatient presentation and antibiotic use. Point-of-care test (POCT) interpretation relates to antibiotic use and antibiotic resistance. We aimed to assess the diagnostic accuracy of POCT and their role in UTI antibiotic stewardship. One-year retrospective analysis in three clinics on the Thailand-Myanmar border of non-pregnant adults presenting with urinary symptoms. POCT (urine dipstick and microscopy) were compared to culture with significant growth classified as pure growth of a single organism >10(5)  CFU/ml. In 247 patients, 82.6% female, the most common symptoms were dysuria (81.2%), suprapubic pain (67.8%) and urinary frequency (53.7%). After excluding contaminated samples, UTI was diagnosed in 52.4% (97/185); 71.1% (69/97) had a significant growth on culture, and >80% of these were Escherichia coli (20.9% produced extended-spectrum β-lactamase (ESBL)). Positive urine dipstick (leucocyte esterase ≥1 and/or nitrate positive) compared against positive microscopy (white blood cell >10/HPF, bacteria ≥1/HPF, epithelial cells <5/HPF) had a higher sensitivity (99% vs. 57%) but a lower specificity (47% vs. 89%), respectively. Combined POCT resulted in the best sensitivity (98%) and specificity (81%). Nearly one in ten patients received an antimicrobial to which the organism was not fully sensitive. One rapid, cost-effective POCT was too inaccurate to be used alone by healthcare workers, impeding antibiotic stewardship in a high ESBL setting. Appropriate prescribing is improved with concurrent use and concordant results of urine dipstick and microscopy. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Agent Based Modeling of Human Gut Microbiome Interactions and Perturbations.

PubMed

Shashkova, Tatiana; Popenko, Anna; Tyakht, Alexander; Peskov, Kirill; Kosinsky, Yuri; Bogolubsky, Lev; Raigorodskii, Andrei; Ischenko, Dmitry; Alexeev, Dmitry; Govorun, Vadim

2016-01-01

Intestinal microbiota plays an important role in the human health. It is involved in the digestion and protects the host against external pathogens. Examination of the intestinal microbiome interactions is required for understanding of the community influence on host health. Studies of the microbiome can provide insight on methods of improving health, including specific clinical procedures for individual microbial community composition modification and microbiota correction by colonizing with new bacterial species or dietary changes. In this work we report an agent-based model of interactions between two bacterial species and between species and the gut. The model is based on reactions describing bacterial fermentation of polysaccharides to acetate and propionate and fermentation of acetate to butyrate. Antibiotic treatment was chosen as disturbance factor and used to investigate stability of the system. System recovery after antibiotic treatment was analyzed as dependence on quantity of feedback interactions inside the community, therapy duration and amount of antibiotics. Bacterial species are known to mutate and acquire resistance to the antibiotics. The ability to mutate was considered to be a stochastic process, under this suggestion ratio of sensitive to resistant bacteria was calculated during antibiotic therapy and recovery. The model confirms a hypothesis of feedbacks mechanisms necessity for providing functionality and stability of the system after disturbance. High fraction of bacterial community was shown to mutate during antibiotic treatment, though sensitive strains could become dominating after recovery. The recovery of sensitive strains is explained by fitness cost of the resistance. The model demonstrates not only quantitative dynamics of bacterial species, but also gives an ability to observe the emergent spatial structure and its alteration, depending on various feedback mechanisms. Visual version of the model shows that spatial structure is a key factor, which helps bacteria to survive and to adapt to changed environmental conditions.

Cost-effectiveness of standard vs intensive antibiotic regimens for transrectal ultrasonography (TRUS)-guided prostate biopsy prophylaxis.

PubMed

Adibi, Mehrad; Pearle, Margaret S; Lotan, Yair

2012-07-01

Multiple studies have shown an increase in the hospital admission rates due to infectious complications after transrectal ultrasonography (TRUS)-guided prostate biopsy (TRUSBx), mostly related to a rise in the prevalence of fluoroquinolone-resistant organisms. As a result, multiple series have advocated the use of more intensive prophylactic antibiotic regimens to augment the effect of the widely used fluoroquinolone prophylaxis for TRUSBx. The present study compares the cost-effectiveness fluoroquinolone prophylaxis to more intensive prophylactic antibiotic regimens, which is an important consideration for any antibiotic regimen used on a wide-scale for TRUSBx prophylaxis. To compare the cost-effectiveness of fluoroquinolones vs intensive antibiotic regimens for transrectal ultrasonography (TRUS)-guided prostate biopsy (TRUSBx) prophylaxis. Risk of hospital admission for infectious complications after TRUSBx was determined from published data. The average cost of hospital admission due to post-biopsy infection was determined from patients admitted to our University hospital ≤1 week of TRUSBx. A decision tree analysis was created to compare cost-effectiveness of standard vs intensive antibiotic prophylactic regimens based on varying risk of infection, cost, and effectiveness of the intensive antibiotic regimen. Baseline assumption included cost of TRUSBx ($559), admission rate (1%), average cost of admission ($5900) and cost of standard and intensive antibiotic regimens of $1 and $33, respectively. Assuming a 50% risk reduction in admission rates with intensive antibiotics, the standard regimen was slightly less costly with average cost of $619 vs $622, but was associated with twice as many infections. Sensitivity analyses found that a 1.1% risk of admission for quinolone-resistant infections or a 54% risk reduction attributed to the more intensive antibiotic regimen will result in cost-equivalence for the two regimens. Three-way sensitivity analyses showed that small increases in probability of admission using the standard antibiotics or greater risk reduction using the intensive regimen result in the intensive prophylactic regimen becoming substantially more cost-effectiveness even at higher costs. As the risk of admission for infectious complications due to TRUSBx increases, use of an intensive prophylactic antibiotic regimen becomes significantly more cost-effective than current standard antibiotic prophylaxis. © 2011 BJU INTERNATIONAL.

The management of acute uncomplicated cystitis in adult women by family physicians in Canada

PubMed Central

McIsaac, Warren J; Prakash, Preeti; Ross, Susan

2008-01-01

INTRODUCTION There are few Canadian studies that have assessed prescribing patterns and antibiotic preferences of physicians for acute uncomplicated cystitis. A cross-Canada study of adult women with symptoms of acute cystitis seen by primary care physicians was conducted to determine current management practices and first-line antibiotic choices. METHODS A random sample of 2000 members of The College of Family Physicians of Canada were contacted in April 2002, and were asked to assess two women presenting with new urinary tract symptoms. Physicians completed a standardized checklist of symptoms and signs, indicated their diagnosis and antibiotics prescribed. A urine sample for culture was obtained. RESULTS Of the 418 responding physicians, 246 (58.6%) completed the study and assessed 446 women between April 2002 and March 2003. Most women (412 of 420, for whom clinical information about antibiotic prescriptions was available) reported either frequency, urgency or painful urination. Physicians would have usually ordered a urine culture for 77.0% of the women (95% CI 72.7 to 80.8) and prescribed an antibiotic for 86.9% of the women (95% CI 83.3 to 90.0). The urine culture was negative for 32.8% of these prescriptions. The most commonly prescribed antibiotic was trimethoprim/sulfamethoxazole (40.8%; 95% CI 35.7 to 46.1), followed by fluoroquinolones (27.4%; 95% CI 22.9 to 32.3) and nitrofurantoin (26.6%; 95% CI 22.1 to 31.4). CONCLUSION Empirical antibiotic prescribing is standard practice in the community, but is associated with high levels of unnecessary antibiotic use. While trimethoprim/sulfamethoxazole is the first-line empirical antibiotic choice, fluoroquinolone antibiotics have become the second most commonly prescribed empirical antibiotic for acute cystitis. The effect of current prescribing patterns on community levels of quinolone-resistant Escherichia coli may need to be monitored. PMID:19436509

In Data We Trust? Comparison of Electronic Versus Manual Abstraction of Antimicrobial Prescribing Quality Metrics for Hospitalized Veterans With Pneumonia.

PubMed

Jones, Barbara E; Haroldsen, Candace; Madaras-Kelly, Karl; Goetz, Matthew B; Ying, Jian; Sauer, Brian; Jones, Makoto M; Leecaster, Molly; Greene, Tom; Fridkin, Scott K; Neuhauser, Melinda M; Samore, Matthew H

2018-07-01

Electronic health records provide the opportunity to assess system-wide quality measures. Veterans Affairs Pharmacy Benefits Management Center for Medication Safety uses medication use evaluation (MUE) through manual review of the electronic health records. To compare an electronic MUE approach versus human/manual review for extraction of antibiotic use (choice and duration) and severity metrics. Retrospective. Hospitalizations for uncomplicated pneumonia occurring during 2013 at 30 Veterans Affairs facilities. We compared summary statistics, individual hospitalization-level agreement, facility-level consistency, and patterns of variation between electronic and manual MUE for initial severity, antibiotic choice, daily clinical stability, and antibiotic duration. Among 2004 hospitalizations, electronic and manual abstraction methods showed high individual hospitalization-level agreement for initial severity measures (agreement=86%-98%, κ=0.5-0.82), antibiotic choice (agreement=89%-100%, κ=0.70-0.94), and facility-level consistency for empiric antibiotic choice (anti-MRSA r=0.97, P<0.001; antipseudomonal r=0.95, P<0.001) and therapy duration (r=0.77, P<0.001) but lower facility-level consistency for days to clinical stability (r=0.52, P=0.006) or excessive duration of therapy (r=0.55, P=0.005). Both methods identified widespread facility-level variation in antibiotic choice, but we found additional variation in manual estimation of excessive antibiotic duration and initial illness severity. Electronic and manual MUE agreed well for illness severity, antibiotic choice, and duration of therapy in pneumonia at both the individual and facility levels. Manual MUE showed additional reviewer-level variation in estimation of initial illness severity and excessive antibiotic use. Electronic MUE allows for reliable, scalable tracking of national patterns of antimicrobial use, enabling the examination of system-wide interventions to improve quality.

All purulence is local – epidemiology and management of skin and soft tissue infections in three urban emergency departments

PubMed Central

2013-01-01

Background Skin and soft tissue infection (SSTIs) are commonly treated in emergency departments (EDs). While the precise role of antibiotics in treating SSTIs remains unclear, most SSTI patients receive empiric antibiotics, often targeted toward methicillin-resistant Staphylococcus aureus (MRSA). The goal of this study was to assess the efficiency with which ED clinicians targeted empiric therapy against MRSA, and to identify factors that may allow ED clinicians to safely target antibiotic use. Methods We performed a retrospective analysis of patient visits for community-acquired SSTIs to three urban, academic EDs in one northeastern US city during the first quarter of 2010. We examined microbiologic patterns among cultured SSTIs, and relationships between clinical and demographic factors and management of SSTIs. Results Antibiotics were prescribed to 86.1% of all patients. Though S. aureus (60% MRSA) was the most common pathogen cultured, antibiotic susceptibility differed between adult and pediatric patients. Susceptibility of S. aureus from ED SSTIs differed from published local antibiograms, with greater trimethoprim resistance and less fluoroquinolone resistance than seen in S. aureus from all hospital sources. Empiric antibiotics covered the resultant pathogen in 85.3% of cases, though coverage was frequently broader than necessary. Conclusions Though S. aureus remained the predominant pathogen in community-acquired SSTIs, ED clinicians did not accurately target therapy toward the causative pathogen. Incomplete local epidemiologic data may contribute to this degree of discordance. Future efforts should seek to identify when antibiotic use can be narrowed or withheld. Local, disease-specific antibiotic resistance patterns should be publicized with the goal of improving antibiotic stewardship. PMID:24359038

Antibacterial activity of exogenous glutathione and its synergism on antibiotics sensitize carbapenem-associated multidrug resistant clinical isolates of Acinetobacter baumannii.

PubMed

Alharbe, Roaa; Almansour, Ayidh; Kwon, Dong H

2017-10-01

A major clinical impact of A. baumannii is hospital-acquired infections including ventilator-associated pneumonia. The treatment of this pathogen is often difficult due to its innate and acquired resistance to almost all commercially available antibiotics. Infections with carbapenem-associated multidrug resistant A. baumannii is the most problematic. Glutathione is a tripeptide thiol-antioxidant and antibacterial activity of exogenous glutathione was reported in some bacteria. However, clinical relevance and molecular details of the antibacterial activity of glutathione are currently unclear. Seventy clinical isolates of A. baumannii including 63 carbapenem-associated multidrug resistant isolates and a type strain A. baumannii ATCC 19606 were used to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Fractional inhibitory concentration (FIC) and time-killing activity with meropenem and/or glutathione were also determined in the carbapenem-associated multidrug resistant isolates. In addition, the roles of exogenous glutathione in multidrug efflux pumps and β-lactamase production were examined. Levels of MIC and MBC were ranged from 10 to 15mM of exogenous glutathione. All tested carbapenem-associated multidrug resistant isolates were sensitized by all tested antibiotics in combination with subinhibitory concentrations of glutathione. FIC levels of glutathione with carbapenem (meropenem) were all<0.5 and the carbapenem-associated multidrug resistant isolates were killed by subinhibitory concentrations of both glutathione and meropenem at>2log10 within 12h, suggesting glutathione synergistically interacts with meropenem. The roles of multidrug efflux pumps and β-lactamase production were excluded for the glutathione-mediated antibiotic susceptibility. Overall results demonstrate that the antibacterial activity of glutathione is clinically relevant and its synergism on antibiotics sensitizes clinical isolates of A. baumannii regardless of their resistance or susceptibility to antibiotics. This finding suggests that exogenous glutathione alone and/or in combination with existing antibiotics may be applicable to treat infections with carbapenem-associated multidrug resistant A. baumannii. Copyright © 2017 Elsevier GmbH. All rights reserved.

Patterns of antibacterials use in intensive care units.

PubMed

Santos, Edilson Floriano Dos; Lauria-Pires, Liana

2010-06-01

To know and compare the patterns of antimicrobials use in intensive care units (ICUs) based on the Anatomical Therapeutic Chemical/Defined Daily Dose (ATC/DDD) system. a prospective cohort study was conducted in three medical-surgical intensive care units, two of them in public hospitals and one in a private hospital. Simple random, independent samples of patients admitted from 10/2004 to 09/2005 to the selected intensive care units were used. The antibiotics use was assessed using the ATC/DDD system. The amount of antibacterials used in each intensive care unit, in grams, was transformed in daily defined dose (DDD). The number of DDDs was divided by the number of patient-days, multiplied by one thousand, to obtain the average density of consumption (DC) per thousand patient-days (DDD1000). 1,728 patients-days and 2,918.6 DDDs were examined in the three intensive care units, corresponding to an average density of consumption of 1,689.0 DDD1000. The median number of DDDs of antibiotics use in the public hospitals’ intensive care units was significantly higher (p=0.002) versus the private hospital’s intensive care unit. The consumption of antibiotics in the private hospital’s intensive care unit (DC=2,191.7 DDD1000) was significantly higher (p<0.001) versus the intensive care units of public hospitals (1,499.5 DDD1000). The most used antibiotics groups in the three intensive care units were 3rd generation cephalosporins, penicillins/betalactamases inhibitors, carbapenems and fluorquinolones. The pattern of antibiotics use in the three examined intensive care units was not uniform. The private hospital’s intensive care unit used a significantly larger amount versus the public hospitals’ intensive care units. Nevertheless, the most used antibiotics groups were similar in the three intensive care units.

Empiric Antibiotic Use and Susceptibility in Infants With Bacterial Infections: A Multicenter Retrospective Cohort Study.

PubMed

Feldman, Elana A; McCulloh, Russell J; Myers, Angela L; Aronson, Paul L; Neuman, Mark I; Bradford, Miranda C; Alpern, Elizabeth R; Balamuth, Frances; Blackstone, Mercedes M; Browning, Whitney L; Hayes, Katie; Korman, Rosalynne; Leazer, Rianna C; Nigrovic, Lise E; Marble, Richard; Roben, Emily; Williams, Derek J; Tieder, Joel S

2017-07-20

To assess hospital differences in empirical antibiotic use, bacterial epidemiology, and antimicrobial susceptibility for common antibiotic regimens among young infants with urinary tract infection (UTI), bacteremia, or bacterial meningitis. We reviewed medical records from infants <90 days old presenting to 8 US children's hospitals with UTI, bacteremia, or meningitis. We used the Pediatric Health Information System database to identify cases and empirical antibiotic use and medical record review to determine infection, pathogen, and antimicrobial susceptibility patterns. We compared hospital-level differences in antimicrobial use, pathogen, infection site, and antimicrobial susceptibility. We identified 470 infants with bacterial infections: 362 (77%) with UTI alone and 108 (23%) with meningitis or bacteremia. Infection type did not differ across hospitals ( P = .85). Empirical antibiotic use varied across hospitals ( P < .01), although antimicrobial susceptibility patterns for common empirical regimens were similar. A third-generation cephalosporin would have empirically treated 90% of all ages, 89% in 7- to 28-day-olds, and 91% in 29- to 89-day-olds. The addition of ampicillin would have improved coverage in only 4 cases of bacteremia and meningitis. Ampicillin plus gentamicin would have treated 95%, 89%, and 97% in these age groups, respectively. Empirical antibiotic use differed across regionally diverse US children's hospitals in infants <90 days old with UTI, bacteremia, or meningitis. Antimicrobial susceptibility to common antibiotic regimens was similar across hospitals, and adding ampicillin to a third-generation cephalosporin minimally improves coverage. Our findings support incorporating empirical antibiotic recommendations into national guidelines for infants with suspected bacterial infection. Copyright © 2017 by the American Academy of Pediatrics.

The Antibio experiment. [Spacelab D1 mission

NASA Technical Reports Server (NTRS)

Lapchine, L.; Moatti, N.; Richoilley, G.; Templier, J.; Gasset, G.; Tixador, R.

1988-01-01

An experiment was flown on Spacelab to confirm the results of the Cytos 2 experiment on Salyut 7, which found an increase in minimal inhibitory concentration in in-flight cultures, i.e., an increase of antibiotic resistance. The 1 g centrifuge on Biorack was also used to differentiate the effects of cosmic rays and microgravity. The antibiotic sensitivity of bacteria cultivated in vitro during orbital flight was studied. The bacteria was E. coli, the antibiotic was Colistin. An increase of antibiotic resistance is observed. Three explanations are offered: stimulation of bacterial proliferation in space; a relationship between the transport of antibiotics into cells and modifications of cellular envelope permeability; and a combined effect of both phenomena.

[Resistance of urinary tract pathogens and the choice of antimicrobial therapy: deceptive simplicity].

PubMed

Rafalskiy, V V; Dovgan, E V

2017-07-01

Urinary tract infection (UTI) is one of the most common reasons for prescribing antibiotics in outpatient and inpatient settings. One of the main criteria for selecting antimicrobial drugs for treating UTI is data on the antibiotic resistance of uropathogens. The article discusses the difficulties in interpreting the results of antimicrobial sensitivity testing of uropathogens and the impact of antibiotic resistance of uropathogens on the clinical effectiveness of managing UTI.

Real-time detection of antibiotic activity by measuring nanometer-scale bacterial deformation

NASA Astrophysics Data System (ADS)

Iriya, Rafael; Syal, Karan; Jing, Wenwen; Mo, Manni; Yu, Hui; Haydel, Shelley E.; Wang, Shaopeng; Tao, Nongjian

2017-12-01

Diagnosing antibiotic-resistant bacteria currently requires sensitive detection of phenotypic changes associated with antibiotic action on bacteria. Here, we present an optical imaging-based approach to quantify bacterial membrane deformation as a phenotypic feature in real-time with a nanometer scale (˜9 nm) detection limit. Using this approach, we found two types of antibiotic-induced membrane deformations in different bacterial strains: polymyxin B induced relatively uniform spatial deformation of Escherichia coli O157:H7 cells leading to change in cellular volume and ampicillin-induced localized spatial deformation leading to the formation of bulges or protrusions on uropathogenic E. coli CFT073 cells. We anticipate that the approach will contribute to understanding of antibiotic phenotypic effects on bacteria with a potential for applications in rapid antibiotic susceptibility testing.

Antibiotic prescription patterns in the empiric therapy of severe sepsis: combination of antimicrobials with different mechanisms of action reduces mortality.

PubMed

Díaz-Martín, Ana; Martínez-González, María Luisa; Ferrer, Ricard; Ortiz-Leyba, Carlos; Piacentini, Enrique; Lopez-Pueyo, Maria Jesus; Martín-Loeches, Ignacio; Levy, Mitchell M; Artigas, Antoni; Garnacho-Montero, José

2012-11-18

Although early institution of adequate antimicrobial therapy is lifesaving in sepsis patients, optimal antimicrobial strategy has not been established. Moreover, the benefit of combination therapy over monotherapy remains to be determined. Our aims are to describe patterns of empiric antimicrobial therapy in severe sepsis, assessing the impact of combination therapy, including antimicrobials with different mechanisms of action, on mortality. This is a Spanish national multicenter study, analyzing all patients admitted to ICUs who received antibiotics within the first 6 hours of diagnosis of severe sepsis or septic shock. Antibiotic-prescription patterns in community-acquired infections and nosocomial infections were analyzed separately and compared. We compared the impact on mortality of empiric antibiotic treatment, including antibiotics with different mechanisms of action, termed different-class combination therapy (DCCT), with that of monotherapy and any other combination therapy possibilities (non-DCCT). We included 1,372 patients, 1,022 (74.5%) of whom had community-acquired sepsis and 350 (25.5%) of whom had nosocomial sepsis. The most frequently prescribed antibiotic agents were β-lactams (902, 65.7%) and carbapenems (345, 25.1%). DCCT was administered to 388 patients (28.3%), whereas non-DCCT was administered to 984 (71.7%). The mortality rate was significantly lower in patients administered DCCTs than in those who were administered non-DCCTs (34% versus 40%; P = 0.042). The variables independently associated with mortality were age, male sex, APACHE II score, and community origin of the infection. DCCT was a protective factor against in-hospital mortality (odds ratio (OR), 0.699; 95% confidence interval (CI), 0.522 to 0.936; P = 0.016), as was urologic focus of infection (OR, 0.241; 95% CI, 0.102 to 0.569; P = 0.001). β-Lactams, including carbapenems, are the most frequently prescribed antibiotics in empiric therapy in patients with severe sepsis and septic shock. Administering a combination of antimicrobials with different mechanisms of action is associated with decreased mortality.

Group A beta-hemolytic streptococcal pharyngitis and carriage rate among Egyptian children: a case-control study.

PubMed

Abd El-Ghany, Shereen Mohamed; Abdelmaksoud, Abeer Ahmed; Saber, Sally Mohamed; Abd El Hamid, Dalia Hosni

2015-01-01

Improper prescription of antibiotics for treatment of acute pharyngitis predisposes to emergence of a carrier state and antibiotic-resistant strains of group A streptococci (GAS). We sought to identify the frequency and antimicrobial susceptibility patterns of group A streptococci among Egyptian children with acute pharyngitis compared with asymptomatic children. Case-control study conducted from September 2013 to August 2014 at a pediatric outpatient clinic in Egypt. Throat swabs were collected from children with acute pharyngitis and from asymptomatic children. We evaluated the accuracy of McIsaac scores and the rapid antigen detection test (RADT) for diagnosis of GAS pharyngitis with throat culture as a reference test. Antimicrobial susceptibility testing of GAS isolates was done by the disc diffusion method. Of 142 children with acute pharyngitis (cases) and 300 asymptomatic children (controls) (age range, 4-16 years), GAS pharyngitis was diagnosed in 60/142 children (42.2%); 48/300 (16%) were found to be carriers. All GAS isolates in the case group were sensitive to penicillin; however, an MIC90 (0.12 micro g/mL) for penicillin is high and an alarming sign. The resistance rate to macrolides was 70% with the cMLSB phenotype in 65.1%. The sensitivities and specificities were 78.3% and 73.2% for McIsaac score of >=4 and 81.1% and 93.9% for RADT, respectively. GAS isolates in the control group were 100% sensitive to penicillin, while 12.5% and 37.5% were resistant to macrolides and tetracycline, respectively. An increased MIC90 for GAS isolates to penicillin is an alarming sign. A high frequency of resistance to macrolides was also observed.

Sequence-Specific Targeting of Bacterial Resistance Genes Increases Antibiotic Efficacy

PubMed Central

Wong, Michael; Daly, Seth M.; Greenberg, David E.; Toprak, Erdal

2016-01-01

The lack of effective and well-tolerated therapies against antibiotic-resistant bacteria is a global public health problem leading to prolonged treatment and increased mortality. To improve the efficacy of existing antibiotic compounds, we introduce a new method for strategically inducing antibiotic hypersensitivity in pathogenic bacteria. Following the systematic verification that the AcrAB-TolC efflux system is one of the major determinants of the intrinsic antibiotic resistance levels in Escherichia coli, we have developed a short antisense oligomer designed to inhibit the expression of acrA and increase antibiotic susceptibility in E. coli. By employing this strategy, we can inhibit E. coli growth using 2- to 40-fold lower antibiotic doses, depending on the antibiotic compound utilized. The sensitizing effect of the antisense oligomer is highly specific to the targeted gene’s sequence, which is conserved in several bacterial genera, and the oligomer does not have any detectable toxicity against human cells. Finally, we demonstrate that antisense oligomers improve the efficacy of antibiotic combinations, allowing the combined use of even antagonistic antibiotic pairs that are typically not favored due to their reduced activities. PMID:27631336

Comparison of Epidemiological and Antibiotic Susceptibility Pattern of Metallo-Beta-Lactamase-Positive and Metallo-Beta-Lactamase-Negative Strains of Pseudomonas Aeruginosa

PubMed Central

Ranjan, Shikha; Banashankari, GS; Babu, PR Sreenivasa

2014-01-01

Background: The infections caused by metallo-beta-lactamases (MBLs) producing Pseudomonas aeruginosa are associated with higher rates of mortality, morbidity, and overall healthcare costs compared to non-MBL P. aeruginosa infections. Purpose: To compare the epidemiologic factors and antibiograms of MBL-positive and MBL-negative P. aeruginosa isolates in a tertiary care hospital. Methods: In an observational study, from January 2011 to December 2012, all non-duplicate P. aeruginosa isolates were subjected to an antimicrobial sensitivity test against 10 antibiotics of five different classes. All P. aeruginosa strains showing resistance to at least one of the carbapenems were subjected to the MBL-E test. Epidemiological features and antibiograms of MBL-positive and MBL-negative strains were compared and statistically analyzed. Results: Out of 350 isolates (total sample = 5330) of P. aeruginosa, MBL was detected in 58 isolates by the E-test, resulting in a prevalence of 16.57%. Resistance to most of the antibiotics was significantly higher in the MBL-positive strains with 100% resistance to ciprofloxacin, tobramycin, and meropenem, followed by imipenem (93.10%) and gentamicin (89.66%). The prevalence of multidrug-resistant and pandrug-resistant strains was significantly higher among the MBL group as compared to that in the non-MBL group ((55.17 vs. 7.88% (P < 0.0001) and 8.62 vs. 0.68% (P = 0.0006)), respectively. Conclusions: MBL-positive P. aeruginosa strains showed very high resistance to various antibiotics, as compared to the non-MBL strains. Increasing prevalence of MBL-producing isolates in hospital settings makes it important to perform routine detection of MBL-positive P. aeruginosa strains by in vitro testing before antibiotic use, for the purposes of infection prevention, and control, and for minimizing the adverse outcomes of infections with MBL-producing strains. PMID:25328336

Astrobiology as a framework for investigating antibiotic susceptibility: a study of Halomonas hydrothermalis

PubMed Central

Cockell, Charles S.

2017-01-01

Physical and chemical boundaries for microbial multiplication on Earth are strongly influenced by interactions between environmental extremes. However, little is known about how interactions between multiple stress parameters affect the sensitivity of microorganisms to antibiotics. Here, we assessed how 12 distinct permutations of salinity, availability of an essential nutrient (iron) and atmospheric composition (aerobic or microaerobic) affect the susceptibility of a polyextremotolerant bacterium, Halomonas hydrothermalis, to ampicillin, kanamycin and ofloxacin. While salinity had a significant impact on sensitivity to all three antibiotics (as shown by turbidimetric analyses), the nature of this impact was modified by iron availability and the ambient gas composition, with differing effects observed for each compound. These two parameters were found to be of particular importance when considered in combination and, in the case of ampicillin, had a stronger combined influence on antibiotic tolerance than salinity. Our data show how investigating microbial responses to multiple extremes, which are more representative of natural habitats than single extremes, can improve our understanding of the effects of antimicrobial compounds and suggest how studies of habitability, motivated by the desire to map the limits of life, can be used to systematically assess the effectiveness of antibiotics. PMID:28123098

Astrobiology as a framework for investigating antibiotic susceptibility: a study of Halomonas hydrothermalis.

PubMed

Harrison, Jesse P; Angel, Roey; Cockell, Charles S

2017-01-01

Physical and chemical boundaries for microbial multiplication on Earth are strongly influenced by interactions between environmental extremes. However, little is known about how interactions between multiple stress parameters affect the sensitivity of microorganisms to antibiotics. Here, we assessed how 12 distinct permutations of salinity, availability of an essential nutrient (iron) and atmospheric composition (aerobic or microaerobic) affect the susceptibility of a polyextremotolerant bacterium, Halomonas hydrothermalis, to ampicillin, kanamycin and ofloxacin. While salinity had a significant impact on sensitivity to all three antibiotics (as shown by turbidimetric analyses), the nature of this impact was modified by iron availability and the ambient gas composition, with differing effects observed for each compound. These two parameters were found to be of particular importance when considered in combination and, in the case of ampicillin, had a stronger combined influence on antibiotic tolerance than salinity. Our data show how investigating microbial responses to multiple extremes, which are more representative of natural habitats than single extremes, can improve our understanding of the effects of antimicrobial compounds and suggest how studies of habitability, motivated by the desire to map the limits of life, can be used to systematically assess the effectiveness of antibiotics. © 2017 The Author(s).

Novel antibacterial activity of monolaurin compared with conventional antibiotics against organisms from skin infections: an in vitro study.

PubMed

Carpo, Beatriz G; Verallo-Rowell, Vermén M; Kabara, Jon

2007-10-01

A cross-sectional laboratory study to determine the in vitro sensitivity and resistance of organisms in culture isolates from skin infections and mechanisms of action of monolaurin, a coconut lauric acid derivative, compared with 6 common antibiotics: penicillin, oxacillin, fusidic acid, mupirocin, erythromycin, and vancomycin. Skin culture samples were taken from newborn to 18-year-old pediatric patients with primary and secondarily infected dermatoses. Samples were collected and identified following standard guidelines, then sent to the laboratory for sensitivity testing against the 6 selected antibiotics and monolaurin. Sensitivity rates of Gram-positive Staphylococcus aureus, Streptococcus spp., and coagulase-negative Staphylococcus, Gram-negative E. vulneris, Enterobacter spp., and Enterococcus spp. to 20 mg/ml monolaurin was 100% and of Klebsiella rhinoscleromatis was 92.31%. Escherichia coli had progressively less dense colony growths at increasing monolaurin concentrations, and at 20 mg/ml was less dense than the control. Staphylococcus aureus, coagulase-negative Staphylococcus, and Streptococcus spp. did not exhibit any resistance to monolaurin and had statistically significant (P <.05) differences in resistance rates to these antibiotics. Monolaurin has statistically significant in vitro broad-spectrum sensitivity against Gram-positive and Gram-negative bacterial isolates from superficial skin infections. Most of the bacteria did not exhibit resistance to it. Monolaurin needs further pharmacokinetic studies to better understand its novel mechanisms of action, toxicity, drug interactions, and proper dosing in order to proceed to in vivo clinical studies.

Prevalence of antibiotic prescription in pediatric outpatients in Italy: the role of local health districts and primary care physicians in determining variation. A multilevel design for healthcare decision support.

PubMed

Di Martino, Mirko; Lallo, Adele; Kirchmayer, Ursula; Davoli, Marina; Fusco, Danilo

2017-11-17

According to scientific literature, antibacterials are prescribed for common pediatric conditions that do not benefit from antibiotic therapy. The link between antibiotic use and bacterial resistance is well known. Antibiotic overprescribing generates high social costs and severe consequences for children. Our objectives were to analyze antibiotic prescription patterns in pediatric outpatients residing in the Lazio region (Italy), to identify physicians' characteristics associated with increased propensity for prescription, to identify the priority axes for action to improve the rational use of antibiotics. We enrolled all children aged 13 years or less in 2014. Antibiotic prescription patterns were analyzed during a one-year follow-up period. The main outcome measures were the antibiotic prescription prevalence, and the geographic variation in antibiotic prescribing. Multilevel models were performed to analyze variation. Variation was expressed as Median Odds Ratios (MORs). If the MOR is 1.00, there is no variation between clusters. If there is considerable between-cluster variation, the MOR will be large. We enrolled 636,911 children. Most of them were aged 6-13 years (57.3%). In 2015, the antibiotic prescription prevalence was 46% in the 0-13, 58% in the 0-5, and 37% in the 6-13 age group. Overall, penicillins were the most prescribed antibiotics, their consumption increased from 43% to 52% during the 2007-2015 period. In 2015, the antibiotic prescription prevalence ranged from 30% to 62% across local health districts (LHDs) of the region. Moreover, a significant (p < 0.001) variation was observed between physicians working in the same LHD: MORs were equal to 1.52 (1.48-1.56) and 1.46 (1.44-1.48) in the 0-5 and 6-13 age groups, respectively. The probability of prescribing antibiotics was significantly (p < 0.001) lower for more-experienced physicians. Pediatric antibiotic use in the Lazio region is much higher than in other European countries. The intra-regional drug prescribing variability underlines the lack of therapeutic protocols shared at regional level and raises equity issues in access to optimal care. Both LHD managers and individual physicians should be involved in training interventions to improve the targeted use of antibiotics and mitigate the effect of contextual variables, such as the spatial-related socioeconomic status of the patient/parent binomial.

Genome-wide analysis captures the determinants of the antibiotic cross-resistance interaction network

PubMed Central

Lázár, Viktória; Nagy, István; Spohn, Réka; Csörgő, Bálint; Györkei, Ádám; Nyerges, Ákos; Horváth, Balázs; Vörös, Andrea; Busa-Fekete, Róbert; Hrtyan, Mónika; Bogos, Balázs; Méhi, Orsolya; Fekete, Gergely; Szappanos, Balázs; Kégl, Balázs; Papp, Balázs; Pál, Csaba

2014-01-01

Understanding how evolution of antimicrobial resistance increases resistance to other drugs is a challenge of profound importance. By combining experimental evolution and genome sequencing of 63 laboratory-evolved lines, we charted a map of cross-resistance interactions between antibiotics in Escherichia coli, and explored the driving evolutionary principles. Here, we show that (1) convergent molecular evolution is prevalent across antibiotic treatments, (2) resistance conferring mutations simultaneously enhance sensitivity to many other drugs and (3) 27% of the accumulated mutations generate proteins with compromised activities, suggesting that antibiotic adaptation can partly be achieved without gain of novel function. By using knowledge on antibiotic properties, we examined the determinants of cross-resistance and identified chemogenomic profile similarity between antibiotics as the strongest predictor. In contrast, cross-resistance between two antibiotics is independent of whether they show synergistic effects in combination. These results have important implications on the development of novel antimicrobial strategies. PMID:25000950

Ribosomal mutations promote the evolution of antibiotic resistance in a multidrug environment.

PubMed

Gomez, James E; Kaufmann-Malaga, Benjamin B; Wivagg, Carl N; Kim, Peter B; Silvis, Melanie R; Renedo, Nikolai; Ioerger, Thomas R; Ahmad, Rushdy; Livny, Jonathan; Fishbein, Skye; Sacchettini, James C; Carr, Steven A; Hung, Deborah T

2017-02-21

Antibiotic resistance arising via chromosomal mutations is typically specific to a particular antibiotic or class of antibiotics. We have identified mutations in genes encoding ribosomal components in Mycobacterium smegmatis that confer resistance to several structurally and mechanistically unrelated classes of antibiotics and enhance survival following heat shock and membrane stress. These mutations affect ribosome assembly and cause large-scale transcriptomic and proteomic changes, including the downregulation of the catalase KatG, an activating enzyme required for isoniazid sensitivity, and upregulation of WhiB7, a transcription factor involved in innate antibiotic resistance. Importantly, while these ribosomal mutations have a fitness cost in antibiotic-free medium, in a multidrug environment they promote the evolution of high-level, target-based resistance. Further, suppressor mutations can then be easily acquired to restore wild-type growth. Thus, ribosomal mutations can serve as stepping-stones in an evolutionary path leading to the emergence of high-level, multidrug resistance.

Multiple antibiotic resistance patterns of rhizospheric bacteria isolated from Phragmites australis growing in constructed wetland for distillery effluent treatment.

PubMed

Chaturvedi, Sonal; Chandra, Ram; Rai, Vibhuti

2008-01-01

Susceptibility patterns of 12 different antibiotics were investigated against rhizospheric bacteria isolated from Phragmites australis from three different zones i.e. upper (0-5 cm), middle (5-10 cm), lower (10-15 cm) in constructed wetland system with and without distillery effluent. The major pollutants of distillery effluent were phenols, sulphide, heavy metals, and higher levels of biological oxygen demand (BOD), chemical oxygen demand (COD) etc. The antibiotic resistance properties of bacteria were correlated with the heavy metal tolerance (one of distillery pollutant). Twenty-two species from contaminated and seventeen species from non-contaminated site were tested by agar disc-diffusion method. The results revealed that more than 63% of total isolates were resistance towards one or more antibiotics tested from all the three different zones of contaminated sites. The multiple-drug resistance property was shown by total 8 isolates from effluent contaminated region out of which 3 isolates were from upper zone, 3 isolates from middle zone and 2 isolates were from lower zone. Results indicated that isolates from contaminated rhizosphere were found more resistant to antibiotics than isolates from non-contaminated rhizosphere. Further this study produces evidence suggesting that tolerance to antibiotics was acquired by isolates for the adaptation and detoxification of all the pollutants present in the effluent at contaminated site. This consequently facilitated the phytoremediation of effluent, which emerges the tolerance and increases resistance to antibiotics.

Bioaccumulation and tissue distribution of antibiotics in wild marine fish from Laizhou Bay, North China.

PubMed

Liu, Sisi; Bekele, Tadiyose-Girma; Zhao, Hongxia; Cai, Xiyun; Chen, Jingwen

2018-08-01

Information about bioaccumulation and tissue distribution of antibiotics in wild marine fish is still limited. In the present study, tissue levels, bioaccumulation and distribution patterns of 9 sulfonamide (SA), trimethoprim (TMP), 5 fluoroquinolone (FQ), and 4 macrolide (ML) antibiotics were investigated in gill, muscle, kidney, and liver tissues of seven wild fish species collected from Laizhou Bay, North China in 2016. All the 19 antibiotics were detected in these fish tissues with the total concentrations ranging from 22ng/g dry weight (dw) to 500ng/g dw. The mean values of logarithm bioaccumulation factors (BAFs) in the gills, muscles, kidneys, and livers ranged from 2.2 to 4.8, 1.9 to 4.0, 2.5 to 4.9, and 2.5 to 5.4, respectively. Log BAFs of antibiotics in these tissues significantly increased (r=0.61-0.77, p<0.001) with their logarithm values of liposome-water distribution coefficient (D lipw ) except in the muscles, suggesting that D lipw can well assess the bioaccumulation potentials of antibiotics in phospholipid-rich tissues. In general, the SAs, TMP, and FQs were primarily accumulated in the muscles and the MLs were primarily in the livers, which may be related to their toxicokinetic processes of these marine fish. The present study for the first time reported the tissue distribution patterns of antibiotics in wild marine fish. Copyright © 2018 Elsevier B.V. All rights reserved.

Antibiotic resistome in a large-scale healthy human gut microbiota deciphered by metagenomic and network analyses.

PubMed

Feng, Jie; Li, Bing; Jiang, Xiaotao; Yang, Ying; Wells, George F; Zhang, Tong; Li, Xiaoyan

2018-01-01

The human gut microbiota is an important reservoir of antibiotic resistance genes (ARGs). A metagenomic approach and network analysis were used to establish a comprehensive antibiotic resistome catalog and to obtain co-occurrence patterns between ARGs and microbial taxa in fecal samples from 180 healthy individuals from 11 different countries. In total, 507 ARG subtypes belonging to 20 ARG types were detected with abundances ranging from 7.12 × 10 -7 to 2.72 × 10 -1 copy of ARG/copy of 16S-rRNA gene. Tetracycline, multidrug, macrolide-lincosamide-streptogramin, bacitracin, vancomycin, beta-lactam and aminoglycoside resistance genes were the top seven most abundant ARG types. The multidrug ABC transporter, aadE, bacA, acrB, tetM, tetW, vanR and vanS were shared by all 180 individuals, suggesting their common occurrence in the human gut. Compared to populations from the other 10 countries, the Chinese population harboured the most abundant ARGs. Moreover, LEfSe analysis suggested that the MLS resistance type and its subtype 'ermF' were representative ARGs of the Chinese population. Antibiotic inactivation, antibiotic target alteration and antibiotic efflux were the dominant resistance mechanism categories in all populations. Procrustes analysis revealed that microbial phylogeny structured the antibiotic resistome. Co-occurrence patterns obtained via network analysis implied that 12 species might be potential hosts of 58 ARG subtypes. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

Development of a suspect and non-target screening approach to detect veterinary antibiotic residues in a complex biological matrix using liquid chromatography/high-resolution mass spectrometry.

PubMed

Solliec, Morgan; Roy-Lachapelle, Audrey; Sauvé, Sébastien

2015-12-30

Swine manure can contain a wide range of veterinary antibiotics, which could enter the environment via manure spreading on agricultural fields. A suspect and non-target screening method was applied to swine manure samples to attempt to identify veterinary antibiotics and pharmaceutical compounds for a future targeted analysis method. A combination of suspect and non-target screening method was developed to identify various veterinary antibiotic families using liquid chromatography coupled with high-resolution mass spectrometry (LC/HRMS). The sample preparation was based on the physicochemical parameters of antibiotics for the wide scope extraction of polar compounds prior to LC/HRMS analysis. The amount of data produced was processed by applying restrictive thresholds and filters to significantly reduce the number of compounds found and eliminate matrix components. The suspect and non-target screening was applied on swine manure samples and revealed the presence of seven common veterinary antibiotics and some of their relative metabolites, including tetracyclines, β-lactams, sulfonamides and lincosamides. However, one steroid and one analgesic were also identified. The occurrence of the identified compounds was validated by comparing their retention times, isotopic abundance patterns and fragmentation patterns with certified standards. This identification method could be very useful as an initial step to screen for and identify emerging contaminants such as veterinary antibiotics and pharmaceuticals in environmental and biological matrices prior to quantification. Copyright © 2015 John Wiley & Sons, Ltd.

Emerge of blaNDM-1 and blaOXA-48-like harboring carbapenem-resistant Klebsiella pneumoniae isolates from hospitalized patients in southwestern Iran.

PubMed

Hosseinzadeh, Zahra; Sedigh Ebrahim-Saraie, Hadi; Sarvari, Jamal; Mardaneh, Jalal; Dehghani, Behzad; Rokni-Hosseini, Seyed Mohammad Hossein; Motamedifar, Mohammad

2018-06-01

One of the most important emerging carbapenem-resistant bacteria is Klebsiella pneumoniae (K. pneumoniae). The present study aimed to investigate the antibiotic susceptibility pattern of K. pneumoniae isolates and detection of carbapenemase producing K. pneumoniae obtained from Iranian hospitalized patients. This cross-sectional study was performed on 211 K. pneumoniae isolates which were recovered from different clinical specimens from 2014 to 2015. Modified Hodge test (MHT) and double disk synergy test (DDST) were done for detection of carbapenemase and metallo-beta-lactamase (MBL) producing K. pneumoniae. The presence of antibiotic resistance determinants was investigated by polymerase chain reaction (PCR) method. The results of antibiotic susceptibility showed that all isolates were resistant to ampicillin, and then mostly resistant to piperacillin and ceftazidime with 76.3% and 66.8%, respectively. On the other hand, the highest sensitivity was toward polymyxin B, followed by carbapenems. Of 29 carbapenem-resistant isolates, all were high-level imipenem-resistant isolates (Minimum inhibitory concentration ≥4), except 4 isolates. The results of MHT and DDST showed that 93.1% (27/29) of carbapenem-resistant isolates were carbapenemase and MBL producing isolates, respectively. The presence of bla NDM-1 and bla OXA-48-like genes was detected in 27 (10.9%) and 2 (0.9%) isolates, respectively. This is the first identification of bla NDM-1 and bla OXA-48-like in K. pneumoniae in Southwestern Iran and the highest reported prevalence of bla NDM in this bacterium from Iran. Since carbapenem-resistant isolates containing New Delhi metallo-beta-lactamase 1 (NDM-1) were almost resistant to all the tested antibiotics, the resistance due to this gene may be increased in the near future as a potential health threat. Copyright © 2017. Published by Elsevier Taiwan LLC.

Incidence of antibiotics resistance among uropathogens in Omani children presenting with a single episode of urinary tract infection.

PubMed

Sharef, Sharef W; El-Naggari, Mohamed; Al-Nabhani, Dana; Al Sawai, Ali; Al Muharrmi, Zakaria; Elnour, Ibtisam

2015-01-01

Urinary tract infection (UTI) is one of the most common community-acquired infections. Different organisms can be the cause of UTI in children, with resistance to antibiotics becoming a significant problem in the choice of treatment. Worldwide studies have documented the prevalence of uropathogens in different countries. However, there is no previous study documenting the incidence of different uropathogens in Oman. We aim to report the most common uropathogens and their antibiotic sensitivity patterns in children presenting with documented, single episode UTI at a tertiary hospital in Oman. A retrospective analysis of all Omani children below 14 years who presented with a case of first documented UTI to SQUH between September 2008 and August 2012 was conducted. Data were obtained from the patients' electronic records in the hospital information system. Data were then analyzed using SSPS (Statistical Package for Social Sciences program, Version 20, IBM, Chicago, IL, USA). In the retrospective review of all urine cultures, 438 positive urine cultures were identified. Out of those, 208 (47.5%) belonged to children with their first episode of UTI. Thirty-three patients were excluded and 75 patients were included in the final analysis. Escherichia coli was the most frequently encountered uropathogen in our cohort (69%), followed by Klebsiella pneumoniae infection (17%). Nearly half (46.6%) of these two common organism were resistant to Cotrimoxazole, while 31% of them were resistant to Augmentin. Twenty-four percent of the E. coli and K. pneumoniae strains were resistant to Cefuroxime, and only 10% were resistant to nitrofurantoin. Both Augmentin and Cotrimoxazole should not be the first line antibiotics to treat UTI. Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Mandible Fracture Complications and Infection: The Influence of Demographics and Modifiable Factors.

PubMed

Odom, Elizabeth B; Snyder-Warwick, Alison K

2016-08-01

Mandible fractures account for 36 to 70 percent of all facial fractures. Despite their high prevalence, the literature lacks a comprehensive review of demographics, fracture patterns, timing of management, antibiotic selection, and outcomes, particularly when evaluating pediatric versus adult patients. The authors aim to determine the complication and infection rates after surgical treatment of mandibular fractures and the bacterial isolates and antibiotic sensitivities from mandible infections after open reduction and internal fixation at their institution. Data were collected retrospectively for all mandible fractures treated at the authors' institution between 2003 and 2013. Patients were divided into pediatric (younger than 16 years) and adult (16 years or older) subgroups. Demographics, fracture location, fracture cause, comorbidities, antibiotic choice, and subsequent complications and infections were analyzed. Data were evaluated using appropriate statistical tests for each variable. Three hundred ninety-five patients were evaluated. Demographics and fracture cause were similar to those reported in current literature. Of the 56 pediatric patients, complications occurred in 5.6 percent. Time from injury to operative intervention did not affect outcome. The complication rate was 17.5 percent and the infection rate was 9.4 percent in the adult subgroup. Time from injury to operative intervention, sex, and edentulism were not significant predictors of complication or infection. Tobacco use, number of fractures, number of fractures fixated, and surgical approach were predictors of complication and infection. Perioperative ampicillin-sulbactam had a significantly lower risk of infection. Certain demographic and operative factors lead to significantly higher risks of complications after surgical management of mandibular fractures. Ampicillin-sulbactam provides effective antibiotic prophylaxis. Risk factor modification may improve outcomes. Risk, IV.

Removal of five fluoroquinolone antibiotics during broiler manure composting.

PubMed

Yang, Bing; Meng, Lei; Xue, Nandong

2018-02-01

Composting is a cost-effective approach for the removal of antibiotics from the environment; however, the consequence of this approach on fluoroquinolone antibiotics is limited. The fate of five representative fluoroquinolone antibiotics, namely ciprofloxacin, enrofloxacin, lomefloxacin, norfloxacin, and sarafloxacin, was investigated in a pilot-scale composting of broiler manure over 42 days. The effect of antibiotic concentrations (at a dose of 15, 30, or 60 mg/kg for each and a control without antibiotic addition) on the composting process was also assessed. The 42-day composting showed 45.3-75.4% of antibiotic removal with species-specific patterns. However, the observed variations in such removal among both antibiotics concentrations and composting times were not significant in most cases, possibly indicating a slight side-effect of the tested antibiotic concentrations on the composting process. To the best of our knowledge, this study is among few studies with a focus on the persistence of fluoroquinolone antibiotics during a pilot-scale composting, which warrants further study in regards to the mechanism underlying the removal of these compounds during composting.

Diversity of herbaceous plants and bacterial communities regulates soil resistome across forest biomes.

PubMed

Hu, Hang-Wei; Wang, Jun-Tao; Singh, Brajesh K; Liu, Yu-Rong; Chen, Yong-Liang; Zhang, Yu-Jing; He, Ji-Zheng

2018-04-24

Antibiotic resistance is ancient and prevalent in natural ecosystems and evolved long before the utilization of synthetic antibiotics started, but factors influencing the large-scale distribution patterns of natural antibiotic resistance genes (ARGs) remain largely unknown. Here, a large-scale investigation over 4000 km was performed to profile soil ARGs, plant communities and bacterial communities from 300 quadrats across five forest biomes with minimal human impact. We detected diverse and abundant ARGs in forests, including over 160 genes conferring resistance to eight major categories of antibiotics. The diversity of ARGs was strongly and positively correlated with the diversity of bacteria, herbaceous plants and mobile genetic elements (MGEs). The ARG composition was strongly correlated with the taxonomic structure of bacteria and herbs. Consistent with this strong correlation, structural equation modelling demonstrated that the positive effects of bacterial and herb communities on ARG patterns were maintained even when simultaneously accounting for multiple drivers (climate, spatial predictors and edaphic factors). These findings suggest a paradigm that the interactions between aboveground and belowground communities shape the large-scale distribution of soil resistomes, providing new knowledge for tackling the emerging environmental antibiotic resistance. © 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.

Effect of Physician Tutorials on Prescribing Patterns of Graduate Physicians.

ERIC Educational Resources Information Center

Klein, Lawrence E.; And Others

1981-01-01

Physicians in an experimental group were surveyed to assess their knowledge of the effectiveness, cost, and side effects of antibiotics, and a tutorial was developed to modify some prescribing patterns. Prescribing patterns were statistically different. (Author/MLW)

A Broad-Spectrum Infection Diagnostic that Detects Pathogen-Associated Molecular Patterns (PAMPs) in Whole Blood.

PubMed

Cartwright, Mark; Rottman, Martin; Shapiro, Nathan I; Seiler, Benjamin; Lombardo, Patrick; Gamini, Nazita; Tomolonis, Julie; Watters, Alexander L; Waterhouse, Anna; Leslie, Dan; Bolgen, Dana; Graveline, Amanda; Kang, Joo H; Didar, Tohid; Dimitrakakis, Nikolaos; Cartwright, David; Super, Michael; Ingber, Donald E

2016-07-01

Blood cultures, and molecular diagnostic tests that directly detect pathogen DNA in blood, fail to detect bloodstream infections in most infected patients. Thus, there is a need for a rapid test that can diagnose the presence of infection to triage patients, guide therapy, and decrease the incidence of sepsis. An Enzyme-Linked Lectin-Sorbent Assay (ELLecSA) that uses magnetic microbeads coated with an engineered version of the human opsonin, Mannose Binding Lectin, containing the Fc immunoglobulin domain linked to its carbohydrate recognition domain (FcMBL) was developed to quantify pathogen-associated molecular patterns (PAMPs) in whole blood. This assay was tested in rats and pigs to explore whether it can detect infections and monitor disease progression, and in prospectively enrolled, emergency room patients with suspected sepsis. These results were also compared with data obtained from non-infected patients with or without traumatic injuries. The FcMBL ELLecSA was able to detect PAMPS present on, or released by, 85% of clinical isolates representing 47 of 55 different pathogen species, including the most common causes of sepsis. The PAMP assay rapidly (<1h) detected the presence of active infection in animals, even when blood cultures were negative and bacteriocidal antibiotics were administered. In patients with suspected sepsis, the FcMBL ELLecSA detected infection in 55 of 67 patients with high sensitivity (>81%), specificity (>89%), and diagnostic accuracy of 0·87. It also distinguished infection from trauma-related inflammation in the same patient cohorts with a higher specificity than the clinical sepsis biomarker, C-reactive Protein. The FcMBL ELLecSA-based PAMP assay offers a rapid, simple, sensitive and specific method for diagnosing infections, even when blood cultures are negative and antibiotic therapy has been initiated. It may help to triage patients with suspected systemic infections, and serve as a companion diagnostic to guide administration of emerging dialysis-like sepsis therapies. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Use of antibiotic-impregnated cement during hip and knee arthroplasty in the United States.

PubMed

Heck, D; Rosenberg, A; Schink-Ascani, M; Garbus, S; Kiewitt, T

1995-08-01

A survey of practicing orthopaedists regarding their use of antibiotic(s) in bone-cement (ABC) was carried out. The initial sampling of 2,139 orthopaedists spanned the continental United States. Responses that passed fail-edit criteria were obtained from 1,015 physicians. Clinical practice patterns are highly variable. Adult reconstructive orthopaedic practitioners' belief in antibiotic(s) in bone-cement for the treatment of patients with previous sepsis is favorable. This opinion can be supported at the guideline level. Guidelines suggesting that liquid antibiotics should not be used as additions to polymethyl methacrylate are also supportable. The need for careful scientific inquiry and cost-effectiveness evaluation of the benefits and risks relating to the use of antibiotic additions to polymethyl methacrylate cement in joint arthroplasty exists. On the basis of such inquiry, educational dissemination to reduce practice variation would be indicated.

Observations of resistance through minimum inhibitory concentrations trends for respiratory specimens of commonly isolated organisms.

PubMed

Gillard, Christopher J; Al-Dahir, Sara; Brakta, Fatima

2016-03-01

The objective of this study was to determine minimum inhibitory concentration (MIC) trends among common bacterial organisms found in respiratory isolates in the trauma intensive care unit setting. In this retrospective observational study, MIC data was reviewed over a three year period from January 2009 to December 2011 for the three most frequently identified organisms isolated from respiratory specimens in a trauma intensive care unit along with corresponding hospital data. The most frequently isolated bacterial species identified were Staphylococcus aureus (229 isolates), Pseudomonas aeruginosa (129 isolates), and Acinetobacter species (87 isolates) in the analysis within our institution from 2009-2011. There was considerable variability among the MIC trends for the analyzed organisms. For Pseudomonas isolates, observed sensitivities were as high as 100% for antibiotics ciprofloxacin and imipenem in 2009, but decreased over the next two years in 2010 and 2011. There was considerable variability among the MIC trends for Acinetobacter over the three year period for the antibiotics tested. The MIC data for most Staphylococcus aureus isolates over the three years were sensitive to vancomycin with little change in the observed MIC data. The data reported is observational and indicates the need for future studies to establish a valid relationship of the MIC data over time in our institution particularly among our gram negative organisms, to monitor patterns of antimicrobial resistance. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

The relationship between a model of end stage liver disease score (MELD score) and the occurrence of spontaneous bacterial peritonitis in liver cirrhotic patients.

PubMed

Gayatri, A A Ayu Yuli; Suryadharma, I G A; Purwadi, N; Wibawa, I D N

2007-01-01

To determine relationship between MELD score and the occurrence of SBP, prevalence of SBP, pattern of bacterial culture and antibiotic susceptibility of causative bacteria of liver cirrhotic patients at Sanglah Hospital. Study design was a cross-sectional analytic study. The population in this study consists of liver cirrhotic patients admitted at Sanglah Hospital Denpasar from June 2005 to February 2006. This result confirmed that the MELD score is a reliable index of disease severity and that higher MELD scores had a significantly more frequent SBP prevalence in patients with a MELD score of 18 or more compared with that in patients with a MELD score of 17 or less (p=0.01; 95% CI = 1.379-15.537). Prevalence of SBP was 30.6%. Thirteen patients (68.4%) had monomicrobial positive culture of Aerob bacteria, consisting of Gram negative bacterias in 10 (77%), with Escherichia coli and Acinettobacter baumanii being the most frequent, and 3 (23%) had Gram positive bacteria. High sensitivity to Cefoperazone, Cefotaxim, Ceftazidime, Cefpirome, Ciprofloxacin, Fosfomicin, Meropenem, Streptomycin, Gentamycin, Trimethoprim/Sulphamethoxazole, were shown. Based on this study we concluded that severe liver cirrhosis with MELD score > or = 18 was associated with an increase risk of SBP, with a prevalence of 30.6%. Common causes of SBP mostly were Escherichia coli and Acinettobacter baumanii, which were sensitive to antibiotic treatment of Cefoperazone, Cefotaxime and Ciprofloxacin.

Bacteria causing bacteremia in pediatric cancer patients presenting with febrile neutropenia--species distribution and susceptibility patterns.

PubMed

Miedema, Karin G E; Winter, Rik H L J; Ammann, Roland A; Droz, Sara; Spanjaard, Lodewijk; de Bont, Eveline S J M; Kamps, Willem A; van de Wetering, Marianne D; Tissing, Wim J E

2013-09-01

Infections are a major cause of morbidity and mortality in pediatric cancer patients. The aim of this study was to establish the microbiological spectrum and the susceptibility patterns of bacteremia-causing bacteria in pediatric cancer patients with febrile neutropenia in relation to the use of prophylactic and empirical antibiotics. We analyzed positive blood cultures of pediatric cancer patients presenting with febrile neutropenia between 2004 and 2011 in Groningen and Amsterdam (the Netherlands) and in Bern (Switzerland), using different antibiotic prophylactic and empirical regimens. A total of 156 patients with 202 bacteremias, due to 248 bacteria species, were enrolled. The majority (73%) of bacteremias were caused by Gram-positive bacteria. Gram-negative bacteria, especially Pseudomonas aeruginosa, were observed significantly more often in Bern, where no fluoroquinolone prophylaxis was used. Ciprofloxacin-resistant bacteria were cultured more often from patients who did receive ciprofloxacin prophylaxis, compared to the patients who did not (57 versus 11%, p = 0.044). Gram-positive bacteria predominated in this study. We showed that the use of prophylactic antibiotics in pediatric cancer patients was associated with increased resistance rates, which needs further study. The strategy for empiric antimicrobial therapy for febrile neutropenia should be adapted to local antibiotic resistance patterns.

Dual Recognition Strategy for Specific and Sensitive Detection of Bacteria Using Aptamer-Coated Magnetic Beads and Antibiotic-Capped Gold Nanoclusters.

PubMed

Cheng, Dan; Yu, Mengqun; Fu, Fei; Han, Weiye; Li, Gan; Xie, Jianping; Song, Yang; Swihart, Mark T; Song, Erqun

2016-01-05

Food poisoning and infectious diseases caused by pathogenic bacteria such as Staphylococcus aureus (SA) are serious public health concerns. A method of specific, sensitive, and rapid detection of such bacteria is essential and important. This study presents a strategy that combines aptamer and antibiotic-based dual recognition units with magnetic enrichment and fluorescent detection to achieve specific and sensitive quantification of SA in authentic specimens and in the presence of much higher concentrations of other bacteria. Aptamer-coated magnetic beads (Apt-MB) were employed for specific capture of SA. Vancomycin-stabilized fluorescent gold nanoclusters (AuNCs@Van) were prepared by a simple one-step process and used for sensitive quantification of SA in the range of 32-10(8) cfu/mL with the detection limit of 16 cfu/mL via a fluorescence intensity measurement. And using this strategy, about 70 cfu/mL of SA in complex samples (containing 3 × 10(8) cfu/mL of other different contaminated bacteria) could be successfully detected. In comparison to prior studies, the developed strategy here not only simplifies the preparation procedure of the fluorescent probes (AuNCs@Van) to a great extent but also could sensitively quantify SA in the presence of much higher concentrations of other bacteria directly with good accuracy. Moreover, the aptamer and antibiotic used in this strategy are much less expensive and widely available compared to common-used antibodies, making it cost-effective. This general aptamer- and antibiotic-based dual recognition strategy, combined with magnetic enrichment and fluorescent detection of trace bacteria, shows great potential application in monitoring bacterial food contamination and infectious diseases.

Clinical characteristics, treatment and outcome of children with Lyme arthritis in Nova Scotia.

PubMed

Glaude, Pier Diane; Huber, Adam M; Mailman, Timothy; Ramsey, Suzanne; Lang, Bianca; Stringer, Elizabeth

2015-10-01

Lyme disease is an emerging problem in Nova Scotia. Lyme arthritis is a late manifestation of Lyme disease. To describe the demographic characteristics, referral patterns and clinical course of children diagnosed with Lyme arthritis in a tertiary care pediatric rheumatology clinic in Nova Scotia. In the present retrospective chart review, subjects diagnosed with Lyme arthritis between 2006 and 2013 were identified through the clinic database. Demographic variables, referral patterns, clinical presentation and information regarding treatment course and outcome were collected. Seventeen patients were identified; 76% presented in 2012 and 2013. In 37.5% of cases, the referring physician suspected Lyme disease. Most patients presented with one or more painful and/or swollen joints; 94% had knee involvement. Only three of 17 patients had a history of erythema migrans and four of 17 recalled a tick bite. Five patients had a history of neurological manifestations consistent with Lyme disease, although, none had a diagnosis made at the time. Arthritis usually resolved after treatment with standard antibiotics; however, at last follow-up, two patients had antibiotic refractory Lyme arthritis, with one having joint damage despite aggressive arthritis treatment. A significant increase in cases of Lyme arthritis has recently been recognized in a pediatric rheumatology clinic in Nova Scotia. A history of a tick bite or erythema migrans were not sensitive markers of Lyme arthritis, and this diagnosis was often not considered by the referring physician. Educational initiatives should be undertaken to increase local awareness of this treatable cause of arthritis in children.

[Susceptibility and resistence of Pseudomonas aeruginosa to antimicrobial agents].

PubMed

Gamero Delgado, M C; García-Mayorgas, A D; Rodríguez, F; Ibarra, A; Casal, M

2007-06-01

Pseudomonas aeruginosa is an opportunistic microorganism that is frequently the cause of nosocomial infections. Multiple mechanisms are involved in its natural and acquired resistance to many of the antimicrobial agents commonly used in clinical practice. The objective of this study was to assess the susceptibility and resistance patterns of P. aeruginosa strains isolated in Hospital Reina Sofia between 2000 and 2005, as well as to analyze the differences between intrahospital and extrahospital isolates in 2005 and to compare the results with those obtained in other studies. A total of 3,019 strains of P. aeruginosa from different hospitals and nonhospital settings were evaluated, taking into consideration their degree of sensitivity to different antibiotics. The MICs were determined by means of the Wider I automated system (Soria Melguizo), taking into consideration the criteria of susceptibility and resistance recommended by MENSURA. Results of the analysis showed that P. aeruginosa maintained similar levels of antimicrobial susceptibility during the period 2000-2005, with increased susceptibility to amikacin, gentamicin and tobramycin. There were also important differences in the degree of susceptibility between intrahospital and extrahospital strains, except for imipenem and fosfomycin. The intrahospital difference in susceptibility was also evaluated, emphasizing the importance of periodically studying susceptibility and resistance patterns of P. aeruginosa in each setting in order to evaluate different therapeutic guidelines, as it is not always advisable to extrapolate data from different regions. These differences can be explained by the different use of antibiotics in each center and the geographic variations of the resistance mechanisms of P. aeruginosa.

Bacterial Contamination of Multi-dose Eye Drops at Ophthalmology Department, University of Gondar, Northwest Ethiopia.

PubMed

Tsegaw, Asegedech; Tsegaw, Asamere; Abula, Tefera; Assefa, Yared

2017-01-01

Ophthalmic solutions used for both diagnostic and therapeutic purposes were found to be contaminated with bacteria pathogens and caused serious ocular infections such as keratitis and endophthalmitis. The objective was to assess the magnitude and pattern of bacterial contamination of multi-dose ophthalmic medications and investigate the drug susceptibility pattern of the isolates in the Department of Ophthalmology at Gondar University Teaching Hospital. A total of 100 ophthalmic medications in-use by patients and eye-care workers have been taken and cultured for potential bacterial contamination in the Microbiology Department after 1 week and >1 week of use. The dropper tip and the residual eye medications were examined for contamination. The contaminating bacteria were identified using a standard procedure and drug susceptibility testing to selected antimicrobial agents was done. Eleven ophthalmic medications were contaminated by different bacterial species with a prevalence of 11%. Multi-use and longer duration of use of eye medications were associated with higher rate of contamination. The contamination level ranges from 0% for antibiotics, 20% for local anesthetics, and 40% for povidone iodine. Among bacteria identified, Staphylococcus aureus and coagulase-negative Staphylococcus species were resistant to methicillin while others were sensitive to the antibiotics tested. The prevalence of contamination was low, but methicillin-resistant Staphylococcus was a potential risk. It is recommended that the Department of Ophthalmology should design set of rules about duration of use and safe handling of ophthalmic medications by the staff and patients.

Urinary tract infections: a retrospective, descriptive study of causative organisms and antimicrobial pattern of samples received for culture, from a tertiary care setting

PubMed Central

Kalal, Bhuvanesh Sukhlal; Nagaraj, Savitha

2016-01-01

Introduction Urinary tract infections (UTI) are common infections encountered by physicians either on an outpatient or inpatient basis. These infections have taken center stage due to increasing resistance being reported for commonly used antibiotics. Understanding the distribution and antibiotic susceptibility patterns of uropathogens would facilitate appropriate therapy. Methods A retrospective analysis of the culture isolates obtained from urine samples received at the Department of Microbiology, St. John’s Medical College Hospital, Bengaluru India, was performed between January 2012 and May 2012. Results Of the 5592 urine specimens received, 28.2% showed significant growth. A total of 1673 identified pathogens were used in the analysis. Escherichia coli (54.6%) was the most common Gram-negative bacillus, followed by Klebsiella species (9.7%) and Pseudomonas species (7.5%). The most common Gram-positive coccus was Enterococcus (8.8%). Most of the Gram-negative isolates were resistant to ampicillin (79.3%) and cephalosporins (60%). Resistance to cephalosporins and fluoroquinolones was higher in isolates from inpatients. Other than Klebsiella spp., all other Enterobacteriaceae were susceptible to carbapenems (93%) and aminoglycosides (85%), whilst fluoroquinolones were effective for all Gram-positive bacteria. Conclusion Due to a high level of antimicrobial resistance amongst the pathogens causing UTI in India, it is cautious to advise or modify therapy, as far as possible, after culture and sensitivity testing have been performed. Regional surveillance programs are warranted for the development of national UTI guidelines. PMID:28053916

Urinary tract infections: a retrospective, descriptive study of causative organisms and antimicrobial pattern of samples received for culture, from a tertiary care setting.

PubMed

Kalal, Bhuvanesh Sukhlal; Nagaraj, Savitha

2016-12-01

Urinary tract infections (UTI) are common infections encountered by physicians either on an outpatient or inpatient basis. These infections have taken center stage due to increasing resistance being reported for commonly used antibiotics. Understanding the distribution and antibiotic susceptibility patterns of uropathogens would facilitate appropriate therapy. A retrospective analysis of the culture isolates obtained from urine samples received at the Department of Microbiology, St. John's Medical College Hospital, Bengaluru India, was performed between January 2012 and May 2012. Of the 5592 urine specimens received, 28.2% showed significant growth. A total of 1673 identified pathogens were used in the analysis. Escherichia coli (54.6%) was the most common Gram-negative bacillus, followed by Klebsiella species (9.7%) and Pseudomonas species (7.5%). The most common Gram-positive coccus was Enterococcus (8.8%). Most of the Gram-negative isolates were resistant to ampicillin (79.3%) and cephalosporins (60%). Resistance to cephalosporins and fluoroquinolones was higher in isolates from inpatients. Other than Klebsiella spp., all other Enterobacteriaceae were susceptible to carbapenems (93%) and aminoglycosides (85%), whilst fluoroquinolones were effective for all Gram-positive bacteria. Due to a high level of antimicrobial resistance amongst the pathogens causing UTI in India, it is cautious to advise or modify therapy, as far as possible, after culture and sensitivity testing have been performed. Regional surveillance programs are warranted for the development of national UTI guidelines.

Effects of Subinhibitory Concentrations of Antibiotics on Alpha-Toxin (hla) Gene Expression of Methicillin-Sensitive and Methicillin-Resistant Staphylococcus aureus Isolates

PubMed Central

Ohlsen, Knut; Ziebuhr, Wilma; Koller, Klaus-Peter; Hell, Wolfgang; Wichelhaus, Thomas A.; Hacker, Jörg

1998-01-01

Concentrations of antibiotics below the MIC are able to modulate the expression of virulence-associated genes. In this study, the influence of subinhibitory doses of 31 antibiotics on the expression of the gene encoding the staphylococcal alpha-toxin (hla), a major virulence factor of Staphylococcus aureus, was investigated with a novel gene fusion protocol. The most striking observation was a strong induction of hla expression by subinhibitory concentrations of β-lactams and an almost complete inhibition of alpha-toxin expression by clindamycin. Whereas glycopeptide antibiotics had no effect, the macrolide erythromycin and several aminoglycosides reduced and fluoroquinolones slightly stimulated hla expression. Furthermore, Northern blot analysis of hla mRNA and Western blot (immunoblot) analysis of culture supernatants of both methicillin-sensitive and methicillin-resistant S. aureus strains revealed that methicillin-induced alpha-toxin expression is a common phenomenon of alpha-toxin-producing strains. Some methicillin-resistant S. aureus isolates produced up to 30-fold more alpha-toxin in the presence of 10 μg of methicillin per ml than in its absence. The results indicate that the novel gene fusion technique is a useful tool for studying the modulation of virulence gene expression by antibiotics. Moreover, the results suggest that the effects of certain antibiotics on virulence properties may be relevant for the management of S. aureus infections. PMID:9797209

Structure of the complex between teicoplanin and a bacterial cell-wall peptide: use of a carrier-protein approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Economou, Nicoleta J.; Zentner, Isaac J.; Lazo, Edwin

2013-04-01

Using a carrier-protein strategy, the structure of teicoplanin bound to its bacterial cell-wall target has been determined. The structure reveals the molecular determinants of target recognition, flexibility in the antibiotic backbone and intrinsic radiation sensitivity of teicoplanin. Multidrug-resistant bacterial infections are commonly treated with glycopeptide antibiotics such as teicoplanin. This drug inhibits bacterial cell-wall biosynthesis by binding and sequestering a cell-wall precursor: a d-alanine-containing peptide. A carrier-protein strategy was used to crystallize the complex of teicoplanin and its target peptide by fusing the cell-wall peptide to either MBP or ubiquitin via native chemical ligation and subsequently crystallizing the protein–peptide–antibiotic complex.more » The 2.05 Å resolution MBP–peptide–teicoplanin structure shows that teicoplanin recognizes its ligand through a combination of five hydrogen bonds and multiple van der Waals interactions. Comparison of this teicoplanin structure with that of unliganded teicoplanin reveals a flexibility in the antibiotic peptide backbone that has significant implications for ligand recognition. Diffraction experiments revealed an X-ray-induced dechlorination of the sixth amino acid of the antibiotic; it is shown that teicoplanin is significantly more radiation-sensitive than other similar antibiotics and that ligand binding increases radiosensitivity. Insights derived from this new teicoplanin structure may contribute to the development of next-generation antibacterials designed to overcome bacterial resistance.« less

A systematic review and meta-analysis of the effects of antibiotic consumption on antibiotic resistance

PubMed Central

2014-01-01

Background Greater use of antibiotics during the past 50 years has exerted selective pressure on susceptible bacteria and may have favoured the survival of resistant strains. Existing information on antibiotic resistance patterns from pathogens circulating among community-based patients is substantially less than from hospitalized patients on whom guidelines are often based. We therefore chose to assess the relationship between the antibiotic resistance pattern of bacteria circulating in the community and the consumption of antibiotics in the community. Methods Both gray literature and published scientific literature in English and other European languages was examined. Multiple regression analysis was used to analyse whether studies found a positive relationship between antibiotic consumption and resistance. A subsequent meta-analysis and meta-regression was conducted for studies for which a common effect size measure (odds ratio) could be calculated. Results Electronic searches identified 974 studies but only 243 studies were considered eligible for inclusion by the two independent reviewers who extracted the data. A binomial test revealed a positive relationship between antibiotic consumption and resistance (p < .001) but multiple regression modelling did not produce any significant predictors of study outcome. The meta-analysis generated a significant pooled odds ratio of 2.3 (95% confidence interval 2.2 to 2.5) with a meta-regression producing several significant predictors (F(10,77) = 5.82, p < .01). Countries in southern Europe produced a stronger link between consumption and resistance than other regions. Conclusions Using a large set of studies we found that antibiotic consumption is associated with the development of antibiotic resistance. A subsequent meta-analysis, with a subsample of the studies, generated several significant predictors. Countries in southern Europe produced a stronger link between consumption and resistance than other regions so efforts at reducing antibiotic consumption may need to be strengthened in this area. Increased consumption of antibiotics may not only produce greater resistance at the individual patient level but may also produce greater resistance at the community, country, and regional levels, which can harm individual patients. PMID:24405683

Phylogenetic group distributions, virulence factors and antimicrobial resistance properties of uropathogenic Escherichia coli strains isolated from patients with urinary tract infections in South Korea.

PubMed

Lee, J H; Subhadra, B; Son, Y-J; Kim, D H; Park, H S; Kim, J M; Koo, S H; Oh, M H; Kim, H-J; Choi, C H

2016-01-01

Urinary tract infections (UTIs) are one of the most common diseases by which humans seek medical help and are caused mainly by uropathogenic Escherichia coli (UPEC). Studying the virulence and antibiotic resistance of UPEC with respect to various phylogenetic groups is of utmost importance in developing new therapeutic agents. Thus, in this study, we analysed the virulence factors, antibiotic resistance and phylogenetic groups among various UPEC isolates from children with UTIs. The phylogenetic analysis revealed that majority of the strains responsible for UTIs belonged to the phylogenetic groups B2 and D. Of the 58 E. coli isolates, 79·31% belonged to group B2, 15·51% to group D, 3·44% to group A and 1·72% to B1. Simultaneously, the number of virulence factors and antibiotic resistance exhibited were also significantly high in groups B2 and D compared to other groups. Among the isolates, 44·8% were multidrug resistant and of that 73% belonged to the phylogenetic group B2, indicating the compatibility of antibiotic resistance and certain strains carrying virulence factor genes. The antibiotic resistance profiling of UPEC strains elucidates that the antimicrobial agents such as chloramphenicol, cefoxitin, cefepime, ceftazidime might still be used in the therapy for treating UTIs. As the antibiotic resistance pattern of uropathogenic Escherichia coli varies depending on different geographical regions, the antibiotic resistance pattern from this study will help the physicians to effectively administer antibiotic therapy for urinary tract infections. In addition, the frequency of virulence factors and antibiotic resistance genes among various phylogenic groups could be effectively used to draw new targets for uropathogenic Escherichia coli antibiotic-independent therapies. The study emphasizes need of public awareness on multidrug resistance and for more prudent use of antimicrobials. © 2015 The Society for Applied Microbiology.

The sludge loading rate regulates the growth and release of heterotrophic bacteria resistant to six types of antibiotics in wastewater activated sludge.

PubMed

Yuan, Qing-Bin; Guo, Mei-Ting; Yang, Jian

2015-01-01

Wastewater treatment plants are considered as hot reservoirs of antimicrobial resistance. However, the fates of antibiotic-resistant bacteria during biological treatment processes and relevant influencing factors have not been fully understood. This study evaluated the effects of the sludge loading rate on the growth and release of six kinds of antibiotic-resistant bacteria in an activated sludge system. The results indicated that higher sludge loading rates amplified the growth of all six types of antibiotic resistant bacteria. The release of most antibiotic-resistant bacteria through both the effluent and biosolids was amplified with increased sludge loading rate. Biosolids were the main pattern for all antibiotic-resistant bacteria release in an activated sludge system, which was determined primarily by their growth in the activated sludge. A higher sludge loading rate reactor tended to retain more antibiotic resistance. An activated sludge system with lower sludge loading rates was considered more conducive to the control of antibiotic resistance.

Genotypic and phenotypic β-lactam resistance and presence of PVL gene in Staphylococci from dry bovine udder

PubMed Central

Sivasailam, Asok; Sasidharan, Suchithra; Kollannur, Justin Davis; Syam, Radhika

2017-01-01

Dairy cows affected with subclinical mastitis can be sources of virulent, antimicrobial-resistant Staphylococci to humans because of the excretion of the bacteria through their milk. This study focussed on the phenotypic and genotypic antibiotic resistance patterns of Staphylococci isolated from dairy cows in early dry period. Among 96 isolates of Gram positive cocci from 157 cows, 76 were identified as Coagulase Negative Staphylococci and the remaining 20 were Staphylococcus aureus. Typical amplicons of coagulase gene were obtained for all 20 samples of S. aureus with three major coagulase types being identified as giving 627 bp (40%), 910 bp (35%) and 710 bp (25%) long PCR products. The groEL gene was amplified in PCR of all 76 isolates of Coagulase Negative Staphylococci, and incubation of PCR products with restriction enzyme PvuII yielded three distinct PCR-RFLP fragment patterns bearing resemblance to S. chromogenes and S. hyicus. Highest sensitivity of Coagulase Negative Staphylococci was noted for Azithromycin (92.5%) and the least to Tetracyclines (76.3%), whereas for S. aureus, it was Cefoperazone (95%) and Azithromycin (72.2%) respectively. Phenotypic resistance to Oxacillin (25 isolates), and Cefoxitin (11 isolates) was detected by dilution method with a commercial strip (Ezy MICTM). Genotypic resistance to β-Lactam antibiotics was found in 65 (34 with mecA gene and 31 with blaZ gene) isolates. Eighteen isolates possessed both the genes, with the PVL gene for virulence being detected in five of them. Nine isolates which had mecA gene were phenotypically susceptible to oxacillin while phenotypic resistance to oxacillin was observed in seven isolates that did not have either mecA or blaZ gene. This is the first report of persistent Staphylococcal infections possessing PVL gene and high level of genotypic resistance to β-Lactam antibiotics in small- holder dairy cattle from India. PMID:29091956

Combined effects of prenatal medication use and delivery type are associated with eczema at age 2 years.

PubMed

Wegienka, G; Havstad, S; Zoratti, E M; Kim, H; Ownby, D R; Johnson, C C

2015-03-01

Separately, prenatal antibiotics and Caesarian delivery have been found to be associated with increased risk of allergic diseases. It is not clear whether these factors may modify the effect of each other. To assess whether the associations between delivery types and eczema, sensitization and total IgE at age 2 years were modified by maternal use of prenatal medications. Prenatal charts of women enrolled in the WHEALS birth cohort were reviewed for delivery mode and medications prescribed and administered throughout their entire pregnancy, including systemic antibiotics and vaginally applied antifungal medications. The associations between the delivery mode and select medications and, eczema, sensitization (≥ 1 of 10 allergen-specific IgE ≥ 0.35 IU/mL) and total IgE at age 2 years were assessed. There was a lower risk of eczema among vaginally vs. c-section born children (relative risk adjusted for race = aRR = 0.77, 95% CI 0.56, 1.05). Although not statistically significantly different, this association was stronger among the subset of children born vaginally to a mother who did not use systemic antibiotics or vaginal antifungal medications (aRR = 0.69, 95% CI 0.44, 1.08) compared to those born vaginally to mothers who used systemic antibiotics or vaginal antifungals (aRR = 0.81, 95% CI 0.57, 1.14). A protective association between vaginal birth and sensitization (aRR = 0.86, 95% CI 0.72, 1.03) was similar for those children born vaginally to a mother who did not (aRR = 0.87, 95% CI 0.69, 1.10) and who did (RR = 0.85, 95% CI 0.70, 1.04) use systemic antibiotics or vaginal antifungal medications. There were no associations with total IgE. Children born vaginally had lower risk of eczema and sensitization compared with those born via c-section; however, the protective association with eczema may be slightly weakened when mothers took systemic antibiotics or vaginally applied medications during pregnancy. © 2014 John Wiley & Sons Ltd.

Virulence, Speciation and Antibiotic Susceptibility of Ocular Coagualase Negative Staphylococci (CoNS)

PubMed Central

Priya, Ravindran; Mythili, Arumugam; Singh, Yendremban Randhir Babu; Sreekumar, Haridas; Manikandan, Palanisamy; Panneerselvam, Kanesan

2014-01-01

Background: Coagulase negative Staphylococci (CoNS) are common inhabitants of human skin and mucous membranes. With the emergence of these organisms as prominent pathogens in patients with ocular infections, investigation has intensified in an effort to identify important virulence factors and to inform new approaches to treatment and prevention. Aim: To isolate CoNS from ocular specimens; to study the possible virulence factors; speciation of coagulase negative staphylococci (CoNS) which were isolated from ocular complications; antibiotic susceptibility testing of ocular CoNS. Materials and Methods: The specimens were collected from the target patients who attended the Microbiology Laboratory of a tertiary care eye hospital in Coimbatore, Tamilnadu state, India. The isolates were subjected to tube and slide coagulase tests for the identification of CoNS. All the isolates were subjected to screening for lipase and protease activities. Screening for other virulence factors viz., slime production on Congo red agar medium and haemagglutination assay with use of 96-well microtitre plates. These isolates were identified upto species level by performing biochemical tests such as phosphatase test, arginine test, maltose and trehalose fermentation tests and novobiocin sensitivity test. The isolates were subjected to antibiotic susceptibility studies, based on the revised standards of Clinical and Laboratory Standards Institutes (CLSI). Results: During the one year of study, among the total 260 individuals who were screened, 100 isolates of CoNS were obtained. Lipolytic activity was seen in all the isolates, whereas 38 isolates showed a positive result for protease. A total of 63 isolates showed slime production. Of 100 isolates, 30 isolates were analyzed for haemagglutination, where 4 isolates showed the capacity to agglutinate the erythrocytes. The results of the biochemical analysis revealed that of the 100 isolates of CoNS, 43% were Staphylococcus epidermidis. The other isolates were identified as S. xylosus (n=8), S. captis (n=16), S. haemolyticus (n=10), S. saccharolyticus (n=2), S. hominis (n=5), S. saprophyticus (n=6) and S. intermedius (n=1). On the other hand, 9 isolates were not identified. In the antibiotic susceptibility analysis, it was found that most of the isolates were sensitive to vancomycin, amikacin and linczolid and resistant to cefatoxime, oxacillin, bacitracin and nalidixic acid. Conclusion: S. epidermidis was found to be predominant in causing the ocular complications. Slime production, heamagglutination, protease and lipase activities could be the putative virulence factors of CoNS. Antibiotic susceptibility patterns of CoNS against antibacterial agents revealed maximum resistance to beta lactam groups, and the resistance was found to be higher to oxacillin, and lowest to vancomycin. PMID:24995181

Characterization of a chromosomally integrated luxCDABE marker for investigation of shiga toxin-producing Escherichia coli O91:H21 shedding in cattle

NASA Astrophysics Data System (ADS)

Hong, Yingying; Mathew, Alan G.

2011-06-01

Shiga toxin-producing Escherichia coli (STEC) O91:H21 has been recognized as a potential life-threatening foodborne pathogen and is commonly involved in human infections in European countries. Fecal shedding of the organism by cattle is considered to be the ultimate source for contaminations. Studies examining STEC shedding patterns often include inoculation of strains carrying antibiotic resistance makers for identifiable recovery. However, indigenous intestinal microflora exhibiting similar antibiotic resistance patterns can confound such studies. Such was the case in a study by our group when attempting to characterize shedding patterns of O91:H21 in calves. A chromosomally integrated bioluminescence marker using a luxCDABE cassette from Photorhabdus luminescens was developed in O91:H21 to overcome such shortcomings of antibiotic resistance markers during animal challenge experiment. The marker was validated in various aspects and was shown to have no impact on metabolic reactions, isotype virulence gene patterns, cost to growth, and additionally demonstrated high in vitro stability. Together, the results indicated that a chromosomally integrated luxCDABE based marker may be a superior system for the study of STEC colonization and shedding in cattle.

Spectrophotometric Investigations of Macrolide Antibiotics: A Brief Review

PubMed Central

Keskar, Mrudul R; Jugade, Ravin M

2015-01-01

Macrolides, one of the most commonly used class of antibiotics, are a group of drugs produced by Streptomyces species. They belong to the polyketide class of natural products. Their activity is due to the presence of a large macrolide lactone ring with deoxy sugar moieties. They are protein synthesis inhibitors and broad-spectrum antibiotics, active against both gram-positive and gram-negative bacteria. Different analytical techniques have been reported for the determination of macrolides such as chromatographic methods, flow injection methods, spectrofluorometric methods, spectrophotometric methods, and capillary electrophoresis methods. Among these methods, spectrophotometric methods are sensitive and cost effective for the analysis of various antibiotics in pharmaceutical formulations as well as biological samples. This article reviews different spectrophotometric methods for the determination of macrolide antibiotics. PMID:26609215

MRSA Incidence and Antibiotic Trends in Urban Hand Infections: A 10-Year Longitudinal Study.

PubMed

Kistler, Justin M; Thoder, Joseph J; Ilyas, Asif M

2018-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is the most reported pathogen in hand infections at urban medical centers throughout the country. Antibiotic sensitivity trends are not well known. The purposes of this study were to examine and determine the drug resistance trends for MRSA infections of the hand and to provide recommendations for empiric antibiotic treatment based on sensitivity profiles. A 10-year longitudinal, retrospective chart review was performed on all culture-positive hand infections encountered at a single urban medical center from 2005 to 2014. The proportions of all organisms were calculated for each year and collectively. MRSA infections were additionally subanalyzed for antibiotic sensitivity. A total of 815 culture-positive hand infections were identified. Overall, MRSA grew on culture in 46% of cases. A trend toward decreasing annual MRSA incidence was noted over the 10-year study period. There was a steady increase in polymicrobial infections during the same time. Resistance to clindamycin increased steadily during the 10-year study, starting at 4% in 2008 but growing to 31% by 2014. Similarly, levofloxacin resistance consistently increased throughout the study, reaching its peak at 56% in 2014. The annual incidence of MRSA in hand infections has declined overall but remains the most common pathogen. There has been an alternative increase in the number of polymicrobial infections. MRSA resistance to clindamycin and levofloxacin consistently increased during the study period. Empiric antibiotic therapy for hand infections should not only avoid penicillin and other beta-lactams but should also consider avoiding clindamycin and levofloxacin for empiric treatment.

LONG-TERM STARVATION-INDUCTED LOSS OF ANTIBIOTIC RESISTANCE IN BACTERIA

EPA Science Inventory

Escherichia coli, Pseudomonas fluorescens, and a Pseudomonas sp. strain 133B containing the pSa plasmid were starved in well water for up to 523 days. here were two patterns of apparent antibiotic resistance loss observed. n Pseudomonas sp. strain 133B, there was no apparent loss...

Association of metal tolerance with multiple antibiotic resistance of bacteria isolated from drinking water.

PubMed

Calomiris, J J; Armstrong, J L; Seidler, R J

1984-06-01

Bacterial isolates from the drinking water system of an Oregon coastal community were examined to assess the association of metal tolerance with multiple antibiotic resistance. Positive correlations between tolerance to high levels of Cu2+, Pb2+, and Zn2+ and multiple antibiotic resistance were noted among bacteria from distribution waters but not among bacteria from raw waters. Tolerances to higher levels of Al3+ and Sn2+ were demonstrated more often by raw water isolates which were not typically multiple antibiotic resistant. A similar incidence of tolerance to Cd2+ was demonstrated by isolates of both water types and was not associated with multiple antibiotic resistance. These results suggest that simultaneous selection phenomena occurred in distribution water for bacteria which exhibited unique patterns of tolerance to Cu2+, Pb2+, and Zn2+ and antibiotic resistance.

Characterisation of antibiotic prescriptions for acute respiratory tract infections in Danish general practice: a retrospective registry based cohort study.

PubMed

Aabenhus, Rune; Hansen, Malene Plejdrup; Saust, Laura Trolle; Bjerrum, Lars

2017-05-19

Inappropriate use of antibiotics is contributing to the increasing rates of antimicrobial resistance. Several Danish guidelines on antibiotic prescribing for acute respiratory tract infections in general practice have been issued to promote rational prescribing of antibiotics, however it is unclear if these recommendations are followed. We aimed to characterise the pattern of antibiotic prescriptions for patients diagnosed with acute respiratory tract infections, by means of electronic prescriptions, labeled with clinical indications, from Danish general practice. Acute respiratory tract infections accounted for 456,532 antibiotic prescriptions issued between July 2012 and June 2013. Pneumonia was the most common indication with 178,354 prescriptions (39%), followed by acute tonsillitis (21%) and acute otitis media (19%). In total, penicillin V accounted for 58% of all prescriptions, followed by macrolides (18%) and amoxicillin (15%). The use of second-line agents increased with age for all indications, and comprised more than 40% of the prescriptions in patients aged >75 years. Women were more often prescribed antibiotics regardless of clinical indication. This is the first Danish study to characterise antibiotic prescription patterns for acute respiratory tract infections by data linkage of clinical indications. The findings confirm that penicillin V is the most commonly prescribed antibiotic agent for treatment of patients with an acute respiratory tract infection in Danish general practice. However, second-line agents like macrolides and amoxicillin with or without clavulanic acid are overused. Strategies to improve the quality of antibiotic prescribing especially for pneumonia, acute otitis media and acute rhinosinusitis are warranted. TRACKING THE OVERUSE OF ANTIBIOTICS: Better adherence to guidelines for prescribing antibiotics for different respiratory tract infections are warranted in Danish general practice. The over-use of antibiotics, particularly so-called 'second-line' agents such as amoxicillin, increases resistance and may lead to a potentially catastrophic scenario where antibiotics are no longer effective. Exactly how widespread the over-use of antibiotics is for different infections, however, is not clear. Rune Aabenhus at the University of Copenhagen and co-workers analyzed primary care data regarding antibiotic prescriptions for acute respiratory tract infections including pneumonia and ear infections in Denmark. They found that penicillin V-the current recommended first-line drug in Scandinavian countries-accounted for 58 per cent of prescriptions, a figure which should be improved. Amoxicillin and macrolides were over-prescribed, particularly in elderly patients. The team also call for further analysis of prescriptions given by out-of-hours clinics.

Antibiotic resistance profile of bacterial isolates from animal farming aquatic environments and meats in a peri-urban community in Daejeon, Korea.

PubMed

Rho, Hyunjin; Shin, Bongjin; Lee, Okbok; Choi, Yu-Hyun; Rho, Jaerang; Lee, Jiyoung

2012-05-01

The increasing usage of antibiotics in the animal farming industry is an emerging worldwide problem contributing to the development of antibiotic resistance. The purpose of this work was to investigate the prevalence and antibiotic resistance profile of bacterial isolates collected from animal farming aquatic environments and meats in a peri-urban community in Daejeon, Korea. In an antibacterial susceptibility test, the bacterial isolates showed a high incidence of resistance (∼26.04%) to cefazolin, tetracycline, gentamycin, norfloxacin, erythromycin and vancomycin. The results from a test for multiple antibiotic resistance indicated that the isolates were displaying an approximately 5-fold increase in the incidence of multiple antibiotic resistance to combinations of two different antibiotics compared to combinations of three or more antibiotics. Most of the isolates showed multi-antibiotic resistance, and the resistance patterns were similar among the sampling groups. Sequencing data analysis of 16S rRNA showed that most of the resistant isolates appeared to be dominated by the classes Betaproteobacteria and Gammaproteobacteria, including the genera Delftia, Burkholderia, Escherichia, Enterobacter, Acinetobacter, Shigella and Pseudomonas.

Prevalence and antibiotic susceptibility profiles of Listeria monocytogenes contamination of chicken flocks and meat in Oyo State, south-western Nigeria: Public health implications.

PubMed

Ishola, O O; Mosugu, J I; Adesokan, H K

2016-09-01

Food contamination with Listeria monocytogenes is on the increase posing threats to public health with growing trends in food products recalls due to suspected Listeria contamination. We conducted a cross-sectional study to determine the prevalence and antibiotic susceptibility profiles of Listeria monocytogenes (Lm) among 71 randomly selected poultry farms in Oyo State, Nigeria. A total of 450 samples comprising cloacal swabs (426) and randomly selected dressed chicken meat (24) were cultured for Lm isolation using BrillianceTM Selective Listeria Agar with antibiotics and microbial load count with Nutrient Agar. Further identification was done using microscopic, biochemical characterization and antibiotic sensitivity tests. Data were analysed using bivariate analysis and student t-test. An overall prevalence of 91.8% Lm contamination was obtained comprising 91.5% (390/426) in cloacal swabs and 95.8% (23/24) in meat. The prevalence of Lm in cloacal samples was significantly associated with poultry type (p = 0.008) and breed (p = 0.000. In addition, all the flocks had at least one positive sample yielding 100% flock prevalence. Antibiotic sensitivity test revealed that most of the isolates were resistant to common antibiotics like Ampicillin-cloxacillin and cefuroxime. The results revealed a high level of contamination with Lm in the poultry flock and meat and the observed resistance to most common antibiotics has implications for future disease control as well as public health. There is need to step up routine screening of food animal products for Listeria contamination as well as measures towards reducing such contaminations.

Antibiotic-Impregnated Central Venous Catheters Do Not Change Antibiotic Resistance Patterns.

PubMed

Turnbull, Isaiah R; Buckman, Sara A; Horn, Christopher B; Bochicchio, Grant V; Mazuski, John E

2018-01-01

Antibiotic-impregnated central venous catheters (CVCs) decrease the incidence of infection in high-risk patients. However, use of these catheters carries the hypothetical risk of inducing antibiotic resistance. We hypothesized that routine use of minocycline and rifampin-impregnated catheters (MR-CVC) in a single intensive care unit (ICU) would change the resistance profile for Staphylococcus aureus. We reviewed antibiotic susceptibilities of S. aureus isolates obtained from blood cultures in a large urban teaching hospital from 2002-2015. Resistance patterns were compared before and after implementation of MR-CVC use in the surgical ICU (SICU) in August 2006. We also compared resistance patterns of S. aureus obtained in other ICUs and in non-ICU patients, in whom MR-CVCs were not used. Data for rifampin, oxacillin, and clindamycin were available for 9,703 cultures; tetracycline resistance data were available for 4,627 cultures. After implementation of MR-CVC use in the SICU, rifampin resistance remained unchanged, with rates the same as in other ICU and non-ICU populations (3%). After six years of use of MR-CVCs in the SICU, the rate of tetracycline resistance was unchanged in all facilities (1%-3%). The use of MR-CVCs was not associated with any change in S. aureus oxacillin-resistance rates in the SICU (66% vs. 60%). However, there was a significant decrease in S. aureus clindamycin resistance (59% vs. 34%; p < 0.05) in SICU patients. Routine use of rifampin-minocycline-impregnated CVCs in the SICU was not associated with increased resistance of S. aureus isolates to rifampin or tetracyclines.

[L forms of Staphylococcus aureus. Behavior of coagulase, hemolytic and desoxyribonuclease activities and antibiotic sensitivity].

PubMed

Loschiavo, F; Giarrizzo, S

1977-01-01

L Forms derived from strains of coagulase positive Staphylococcus aureus, have, on the whole, preserved their DNAsic, haemolitic and coagulastic activities. L. forms showed high resistence to antibiotics acting on the bacterial cell-wall. The sensibility to other antibiotics was, roughly, analogous for the L forms as well as for the bacterial strains ones, with the exception of the clortetraciclin and the diidrostreptomicin, ehich proved to be comparatively more active on the L forms.

[A case of nonclostridial gas gangrene of the leg complicated by severe pneumonia].

PubMed

Matsui, Seiko; Baba, Kenji; Suzuki, Kiyoshi; Yamaguchi, Etsuro

2005-10-01

A 73-year-old man admitted for febrile left leg pain with dyspnea, who had poorly controlled diabetes was found on admission to have severe hypoxia and chest X-ray showed infiltrates in the middle to lower left lung. X-rays of the left leg showed gas around the knee joint. These findings suggested severe pneumonia with gas gangrene, necessitating immediate debridement of the gas gangrene lesion and hyperbaric oxygenation. Antibiotics were also administered intravenously (panipenem/betamipron 0.5 g x 3/day, clindamycin 600 mg x 2/day, and erythromycin 500 mg x 3/day). We conducted fiberoptic bronchoscope daily because consolidation of the whole left lung developed with purulent sputum expectoration. Both pneumonia and gas gangrene gradually ameliorated avoiding amputation of theleg. Gas gangrene was cured without leaving sequelae such as motor dysfunction. Staphylococcus aureus was detected in both pus from the leg and sputum collected by bronchoscopy. Microorganisms showed the same pattern of sensitivity to antibiotics, suggesting a causal relationship between pneumonia and gas gangrene through the blood stream. Gas gangrene was considered the primary infection followed by pneumonia, since pain and swelling of the left leg preceded the airway symptoms. The present case illustrates in compromised hosts including diabetics, gas gangrene may develop taking an opportunity of airway infection, and that in some cases, early debridement of the lesion and optimal use of antibiotics may help cure this disease without aggressive surgery. Hyperbaric oxygenation may also be useful, although its validity must be investigated further.

Inhibitors of LexA Autoproteolysis and the Bacterial SOS Response Discovered by an Academic-Industry Partnership.

PubMed

Mo, Charlie Y; Culyba, Matthew J; Selwood, Trevor; Kubiak, Jeffrey M; Hostetler, Zachary M; Jurewicz, Anthony J; Keller, Paul M; Pope, Andrew J; Quinn, Amy; Schneck, Jessica; Widdowson, Katherine L; Kohli, Rahul M

2018-03-09

The RecA/LexA axis of the bacterial DNA damage (SOS) response is a promising, yet nontraditional, drug target. The SOS response is initiated upon genotoxic stress, when RecA, a DNA damage sensor, induces LexA, the SOS repressor, to undergo autoproteolysis, thereby derepressing downstream genes that can mediate DNA repair and accelerate mutagenesis. As genetic inhibition of the SOS response sensitizes bacteria to DNA damaging antibiotics and decreases acquired resistance, inhibitors of the RecA/LexA axis could potentiate our current antibiotic arsenal. Compounds targeting RecA, which has many mammalian homologues, have been reported; however, small-molecules targeting LexA autoproteolysis, a reaction unique to the prokaryotic SOS response, have remained elusive. Here, we describe the logistics and accomplishments of an academic-industry partnership formed to pursue inhibitors against the RecA/LexA axis. A novel fluorescence polarization assay reporting on RecA-induced self-cleavage of LexA enabled the screening of 1.8 million compounds. Follow-up studies on select leads show distinct activity patterns in orthogonal assays, including several with activity in cell-based assays reporting on SOS activation. Mechanistic assays demonstrate that we have identified first-in-class small molecules that specifically target the LexA autoproteolysis step in SOS activation. Our efforts establish a realistic example for navigating academic-industry partnerships in pursuit of anti-infective drugs and offer starting points for dedicated lead optimization of SOS inhibitors that could act as adjuvants for current antibiotics.

Nosocomial pathogens associated with the mobile phones of healthcare workers in a hospital in Anyigba, Kogi state, Nigeria.

PubMed

Nwankwo, E O; Ekwunife, N; Mofolorunsho, K C

2014-06-01

Mobile phones of healthcare workers (HCWs) could be colonized by potential bacteria pathogens. The aim of this research is to evaluate the bacterial contamination and antibiotic sensitivity pattern of isolates from mobile phones of HCWs in Grimad hospital. A total of 112 swab samples were collected from the mobile phones of HCWs and students in June 2012 in Anyigba. While 56 samples were from HCWs in Grimad hospital, 56 samples were obtained from non-healthcare workers (NHCWs) who served as the control. The samples were all screened for bacterial pathogens by standard bacteriological procedures. Antibiotic susceptibility testing was done by the disc diffusion technique. The rate of bacterial contamination of mobile phones of HCWs was 94.6%. Bacteria isolated from mobile phones of HCWs were more resistant to antibiotics than NHCWs phones. Staphylococcus Epidermidis (42.9%) was the most frequently isolated bacteria followed by Bacillus spp. (32.1%), Staphylococcus Aureus (25%), Pseudomonas Aeruginosa (19.6%), Escherichia Coli (14.3%), Streptococcus spp. (14.3%), Proteus spp. (12.5%), Klebsiella spp. (7.1%), and Acinetobacter spp. (5.3%). Cotrimoxazole, ampicillin and tetracycline showed high levels of resistance while gentamicin, ciprofloxacin and ceftriaxone exhibited encouraging results. The presence of bacteria pathogens associated with nosocomial infection was identified. Transmission of pathogens can be reduced by hand hygiene and regular cleaning of mobile phones. Copyright © 2013 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

Feasibility and effectiveness of a low cost campaign on antibiotic prescribing in Italy: community level, controlled, non-randomised trial.

PubMed

Formoso, Giulio; Paltrinieri, Barbara; Marata, Anna Maria; Gagliotti, Carlo; Pan, Angelo; Moro, Maria Luisa; Capelli, Oreste; Magrini, Nicola

2013-09-12

To test the hypothesis that a multifaceted, local public campaign could be feasible and influence antibiotic prescribing for outpatients. Community level, controlled, non-randomised trial. Provinces of Modena and Parma in Emilia-Romagna, northern Italy, November 2011 to February 2012. 1,150,000 residents of Modena and Parma (intervention group) and 3,250,000 residents in provinces in the same region but where no campaign had been implemented (control group). Campaign materials (mainly posters, brochures, and advertisements on local media, plus a newsletter on local antibiotic resistance targeted at doctors and pharmacists). General practitioners and paediatricians in the intervention area participated in designing the campaign messages. Primary outcome was the average change in prescribing rates of antibiotics for outpatient in five months, measured as defined daily doses per 1000 inhabitants/day, using health districts as the unit of analysis. Antibiotic prescribing was reduced in the intervention area compared with control area (-4.3%, 95% confidence interval -7.1% to -1.5%). This result was robust to "sensitivity analysis" modifying the baseline period from two months (main analysis) to one month. A higher decrease was observed for penicillins resistant to β lactamase and a lower decrease for penicillins susceptible to β lactamase, consistent with the content of the newsletter on antibiotic resistance directed at health professionals. The decrease in expenditure on antibiotics was not statistically significant in a district level analysis with a two month baseline period (main analysis), but was statistically significant in sensitivity analyses using either a one month baseline period or a more powered doctor level analysis. Knowledge and attitudes of the target population about the correct use of antibiotics did not differ between the intervention and control areas. A local low cost information campaign targeted at citizens, combined with a newsletter on local antibiotic resistance targeted at doctors and pharmacists, was associated with significantly decreased total rates of antibiotic prescribing but did not affect the population's knowledge and attitudes about antibiotic resistance. ClinicalTrials.gov NCT01604096.

Antibiotic prescribing in dental practice in Belgium.

PubMed

Mainjot, A; D'Hoore, W; Vanheusden, A; Van Nieuwenhuysen, J-P

2009-12-01

To assess the types and frequency of antibiotic prescriptions by Belgian dentists, the indications for antibiotic prescription, and dentists' knowledge about recommended practice in antibiotic use. In this cross-sectional survey, dental practitioners were asked to record information about all antibiotics prescribed to their patients during a 2-week period. The dental practitioners were also asked to complete a self-administered questionnaire regarding demographic data, prescribing practices, and knowledge about antibiotic use. A random sample of 268 Belgian dentists participated in the survey. During the 2-week period, 24 421 patient encounters were recorded; 1033 patients were prescribed an antibiotic (4.2%). The median number of prescriptions per dentist for the 2 weeks was 3. Broad spectrum antibiotics were most commonly prescribed: 82% of all prescriptions were for amoxycillin, amoxycillin-clavulanic acid and clindamycin. Antibiotics were often prescribed in the absence of fever (92.2%) and without any local treatment (54.2%). The most frequent diagnosis for which antibiotics were prescribed was periapical abscess (51.9%). Antibiotics were prescribed to 63.3% of patients with periapical abscess and 4.3% of patients with pulpitis. Patterns of prescriptions were confirmed by the data from the self-reported practice. Discrepancies between observed and recommended practice support the need for educational initiatives to promote rational use of antibiotics in dentistry in Belgium.

Campaign Preparation for Complex Initiatives: A Person-Centered Approach to Audience Segmentation of Parents' Antibiotic Stewardship.

PubMed

Smith, Rachel A; MacGeorge, Erina L; Hackman, Nicole M; M'ikanatha, Nkuchia M

2017-10-25

The evolution of antibiotic resistance is outpacing the speed at which new antibiotics will reach the marketplace. To slow the rate of resistance, people need to engage in antibiotic stewardship, which includes acts to prevent the spread of bacteria and judicious use of antibiotics to treat infections. This study identified the patterns and predictors of antibiotic stewardship behaviors of parents (N = 516) related to their children. The latent class analysis revealed three profiles of parental stewardship, labeled Stewards, Requesters, and Non-Stewards. The findings implied different campaign goals: to encourage Stewards to follow through on their intentions, to encourage Requesters to stop asking providers for antibiotics when their children have ear infections, and to influence Non-Stewards to accept medical advice when an antibiotic is not indicated and to dispose of leftover antibiotics. The covariate analysis provided theoretical insight into the strategies to pursue in campaigns targeting these three groups. For example, parents who perceived antibiotic-resistant infections as less serious health conditions, felt less worry when thinking about their child getting an antibiotic-resistant infection, and had stronger misattributions of antibiotics' efficacy to treat multiple symptoms were more likely to be Requesters and Non-Stewards, instead of Stewards.

Antimicrobial sensitivity pattern of Salmonella: comparison of isolates from HIV-infected and HIV-uninfected patients.

PubMed

Wolday, D; Erge, W

1998-07-01

A retrospective analysis of all cases of Salmonella infections occurring between 1991 and 1995 was undertaken in order to evaluate the antimicrobial sensitivity pattern of the isolates from both human immunodeficiency virus (HIV) infected and uninfected Ethiopian patients. During the 5-year study period, we identified 147 cases of Salmonella infections. Only in 49 cases was the HIV serostatus known; 22 (44.9%) of the infections were in HIV seronegative patients while 27 (55.9%) were in HIV seropositive patients. The strains were isolated from blood (71.4%), urine (18.4%) and stool (8.2%). Salmonella infection was found to be more frequent (55.15% versus 44.9%) among HIV positive than HIV-negative patients. Moreover, Salmonella isolates recovered from HIV-seropositive patients were significantly resistant to many of the antibiotics tested when compared to the isolates from HIV-seronegative patients. The only chloramphenicol resistant Salmonella typhi occurred in a patient who was seropositive for HIV. According to these results, Ethiopian patients infected with HIV may be at risk of acquiring infections, especially non-typhoidal salmonellas, that are multi-drug resistant (MDR) strains than HIV-uninfected subjects. The emergence of MDR Salmonella infection among HIV-positive patients requires reassessment of chemotherapeutic approaches in this patient population, and warrants continued laboratory surveillance.

Effectiveness of simple control measures on methicillin-resistant Staphylococcus aureus infection status and characteristics with susceptibility patterns in a teaching hospital in Peshawar.

PubMed

Rafiq, Muhammad Salman; Rafiq, Muhammad Imran; Khan, Taimur; Rafiq, Maria; Khan, Mah Muneer

2015-09-01

To determine the effectiveness of simple control measures on the infection status and characteristics of methicillin-resistant Staphylococcus aureus including susceptibility patterns among health professionals and patients in a teaching hospital. The cross-sectional study was conducted from September 2013 to January 2014, and comprised samples collected from healthcare personnel and patients in the various units of Khyber Teaching Hospital, Peshawar. The specimens were collected before and one month after the implementation of simple control measures for outbreak prevention of methicillin-resistant Staphylococcus aureus. These were tested for culture and antimicrobial susceptibility. Data about methicillin-sensitive and methicillin-resistant Staphylococcus aureus infection, wound characteristics and susceptibility patterns was collected and effectiveness of simple control measures was determined. SPSS 20 was used for statistical analysis. Of the total 390 isolates, 180(46.2%) were Staphylococcus aureus; 77(19.7%) from healthcare personnel and 103(26.4%) from patients. Of these, 164(42.1%) were methicillin-sensitive and 16(4.1%) were methicillin-resistant. Among the patients, 38(15.1%) methicillin-sensitive and 8(3.2%) methicillin-resistant isolates were recovered from wounds or skin and soft tissues. Pus with 33(13.1%) and 4(1.6%) cases respectively was the second most common source. Among methicillin-resistant isolates, resistance to Linezolid was 0%, all were resistant to Oxacillin, Cefoxitin, Amoxicillin, Cefotaxime and Cephradine, and resistance to both Co-Amoxiclav and Ciprofloxacin was 87.5%. After one month of implementation of simple control measures, the number of methicillin-resistant cases among healthcare professionals and patients dropped from 4(2.9%) and 7(10.8%) to 1(0.7%) and 5(2.7%), respectively. Methicillin-resistant and methicillin-sensitive Staphylococcus aureus differed in their anti-microbial susceptibility profiles. Selection of antibiotics based on susceptibility and culture is needed for prevention of resistance and effective treatment. A decrease was observed in methicillin-resistant cases with implementation of control measures.

[Secretion analysis of pathogenic bacteria culture in 115 rural chronic nasal-sinusitis patients].

PubMed

Zhang, Xiaoyuan; Sun, Jingwu; Chu, Shu

2014-05-01

To investigate the bacteria distribution, drug bacterial sensitivity characteristics of the rural chronic rhinosinusitis (CRS). And to explore the effect of antibiotic on pathogenic bacteria culture. Choose nasal sinus secretions from 115 CRS patients living in rural areas. Aerobic bacteria culture, anaerobic bacteria culture and drug sensitive test were procedured for each sample. At the same time the use of antibiotics nearly 2 months and nearly 2 weeks were collected. Among one hundred and fifteen specimens, 17 kinds of germs were detected in 37 cases, the positive rate of aerobic bacteria was 32.17%. Staphylococcus aureus and epidermis staphylococcus aureus the most common type of aerobe in CRS patients at rural areas. There was negative result in the anaerobic bacteria culture of 17 maxillary sinus specimen. The cases of using antibiotics nearly 2 months was up to 90, accounting for 78.26%. Nearly 2 weeks, 73 cases, accounting for 63.48%. The chi-square analysis showed high bacterial culture rate, in chronic rhinosinusitis with nasal polyps (CRSwNP group), which revealed correlation between bacterial infection factors and nasal polyps formation. For CRS patients with positive result of bacterial culture, they were sensitive to ofloxacin, cefotaxime, organism, ciprofloxacin, magnitude cephalosporin, and were drug fast to penicillin G, ampicillin, erythromycin. No specific differences was found in the bacteria distribution of rural CRS. antibiotics abusage in rural CRS patients and the anaerobic bacteria culture techniques is the main factor resulting in low culture rate. Rational use of antimicrobial agents should be established on the basis of the bacterial culture and drug sensitive test.

Bacteria in the apical root canals of teeth with apical periodontitis.

PubMed

Lee, Li-Wan; Lee, Ya-Ling; Hsiao, Sheng-Huang; Lin, Hung-Pin

2017-06-01

Bacteria in the tooth root canal may cause apical periodontitis. This study examined the bacterial species present in the apical root canal of teeth with apical periodontitis. Antibiotic sensitivity tests were performed to evaluate whether these identified bacterial species were susceptible to specific kinds of antibiotics. Selective media plating and biochemical tests were used first to detect the bacterial species in samples taken from the apical portion of root canals of 62 teeth with apical periodontitis. The isolated bacterial species were further confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry. We found concomitant presence of two (32 teeth) or three species (18 teeth) of bacteria in 50 (80.6%) out of 62 tested teeth. However, only 34 bacterial species were identified. Of a total of 118 bacterial isolates (83 anaerobes and 35 aerobes), Prophyromonas endodontalis was detected in 10; Bacteroides, Dialister invisus or Fusobacterium nucleatum in 9; Treponema denticola or Enterococcus faecalis in 8; Peptostreptococcus or Olsenella uli in 6; and Veillonella in 5 teeth. The other 25 bacterial species were detected in fewer than five teeth. Approximately 80-95% of bacterial isolates of anaerobes were sensitive to ampicillin/sulbactam (Unasyn), amoxicillin/clavulanate (Augmentin), cefoxitin, and clindamycin. For E. faecalis, 85-90% of bacterial isolates were sensitive to gentamicin and linezolid. Root canal infections are usually caused by a mixture of two or three species of bacteria. Specific kinds of antibiotic can be selected to control these bacterial infections after antibiotic sensitivity testing. Copyright © 2016. Published by Elsevier B.V.

Mannitol Enhances Antibiotic Sensitivity of Persister Bacteria in Pseudomonas aeruginosa Biofilms

PubMed Central

Barraud, Nicolas; Buson, Alberto; Jarolimek, Wolfgang; Rice, Scott A.

2013-01-01

The failure of antibiotic therapies to clear Pseudomonas aeruginosa lung infection, the key mortality factor for cystic fibrosis (CF) patients, is partly attributed to the high tolerance of P. aeruginosa biofilms. Mannitol has previously been found to restore aminoglycoside sensitivity in Escherichia coli by generating a proton-motive force (PMF), suggesting a potential new strategy to improve antibiotic therapy and reduce disease progression in CF. Here, we used the commonly prescribed aminoglycoside tobramycin to select for P. aeruginosa persister cells during biofilm growth. Incubation with mannitol (10–40 mM) increased tobramycin sensitivity of persister cells up to 1,000-fold. Addition of mannitol to pre-grown biofilms was able to revert the persister phenotype and improve the efficacy of tobramycin. This effect was blocked by the addition of a PMF inhibitor or in a P. aeruginosa mutant strain unable to metabolise mannitol. Addition of glucose and NaCl at high osmolarity also improved the efficacy of tobramycin although to a lesser extent compared to mannitol. Therefore, the primary effect of mannitol in reverting biofilm associated persister cells appears to be an active, physiological response, associated with a minor contribution of osmotic stress. Mannitol was tested against clinically relevant strains, showing that biofilms containing a subpopulation of persister cells are better killed in the presence of mannitol, but a clinical strain with a high resistance to tobramycin was not affected by mannitol. Overall, these results suggest that in addition to improvements in lung function by facilitating mucus clearance in CF, mannitol also affects antibiotic sensitivity in biofilms and does so through an active, physiological response. PMID:24349568

Electrochemical Quartz Crystal Nanobalance (EQCN) Based Biosensor for Sensitive Detection of Antibiotic Residues in Milk.

PubMed

Bhand, Sunil; Mishra, Geetesh K

2017-01-01

An electrochemical quartz crystal nanobalance (EQCN), which provides real-time analysis of dynamic surface events, is a valuable tool for analyzing biomolecular interactions. EQCN biosensors are based on mass-sensitive measurements that can detect small mass changes caused by chemical binding to small piezoelectric crystals. Among the various biosensors, the piezoelectric biosensor is considered one of the most sensitive analytical techniques, capable of detecting antigens at picogram levels. EQCN is an effective monitoring technique for regulation of the antibiotics below the maximum residual limit (MRL). The analysis of antibiotic residues requires high sensitivity, rapidity, reliability and cost effectiveness. For analytical purposes the general approach is to take advantage of the piezoelectric effect by immobilizing a biosensing layer on top of the piezoelectric crystal. The sensing layer usually comprises a biological material such as an antibody, enzymes, or aptamers having high specificity and selectivity for the target molecule to be detected. The biosensing layer is usually functionalized using surface chemistry modifications. When these bio-functionalized quartz crystals are exposed to a particular substance of interest (e.g., a substrate, inhibitor, antigen or protein), binding interaction occurs. This causes a frequency or mass change that can be used to determine the amount of material interacted or bound. EQCN biosensors can easily be automated by using a flow injection analysis (FIA) setup coupled through automated pumps and injection valves. Such FIA-EQCN biosensors have great potential for the detection of different analytes such as antibiotic residues in various matrices such as water, waste water, and milk.

[Changes in ion transport through membranes, ATPase activity and antibiotics effects in Enterococcus hirae after low intensity electromagnetic irradiation of 51,8 and 53,0 GHz frequencies].

PubMed

Torgomian, É; Oganian, V; Blbulian, C; Trchunian, A

2013-01-01

It was ascertained that one-hour exposure of Enterococcus hirae ATCC9790 bacteria grown under anaerobe condition during sugar (glucose) fermentation to coherent electromagnetic irradiation (EMI) of 51,8 and 53,0 GHz frequencies or millimeter waves (5,79 and 5,66 mm wavelengths) of low-intensity (flux capacity of 0,06 mW/sm2) caused a significant decrease in energy-dependent H+ and K+ transports across the membranes of whole cells. Therewith, K+ influx into cells was appreciably less at the frequency of 53,0 GHz. Likewise, a significant decrease of total and N,N'-dicyclohexylcarbodiimide-sensitive ATPase activity of the membrane vesicles occurred after EMI of 51,8 and 53,0 GHz. These results indicated the input of membranous changes in bacterial action of low intensity extremely high frequency EMI, when the F0F1-ATPase was probably playing a key role. Additionally, the enhancement of the effects of antibiotics--ceftriaxone, kanamycin and ampicillin at their minimal inhibitory concentrations (100, 200 and 1,4 microM, correspondingly) on the bacterial growth by these irradiations was shown. Also, combined action of EMI and antibiotics depressed strongly H+ and K+ fluxes across membrane. Especially, H+ flux was more sensitive to the action of ceftriaxone, but K+ flux was sensitive to kanamycin. All these made the assumption that EMI of 51,8 and 53,0 GHz frequencies, especially 53,0 GHz, was followed by change in bacterial sensitivity toward antibiotics that was more obvious with ceftriaxone and ampicillin.

Clinicomicrobiological profile of endophthalmitis: A 10 year experience in a Tertiary Care Center in North India.

PubMed

Satpathy, Gita; Nayak, Niranjan; Wadhwani, Meenakshi; Venkwatesh, Pradeep; Kumar, Atul; Sharma, Yograj; Sreenivas, Vishnu

2017-01-01

To determine the clinicomicrobiological profile of infectious agents and their antibiotic susceptibility in different type of endophthalmitis. A retrospective review of clinical and microbiological records from January 2001 to December 2010, was performed in 1110 patients diagnosed with different type of endophthalmitis (postoperative, posttraumatic, endogenous and post keratitis) to record the demographic details, clinical presentations; microbiological agents isolated with their antimicrobial sensitivity pattern. Antimicrobial susceptibility testing for various culture positive isolates (bacterial/fungal) was performed by the disc diffusion technique. Out of the 1110 intra-ocular specimens processed, 384 (34.6%) were positive for bacteria. S epidermidis was the most predominant isolate accounting for 42.7% of all bacteria obtained, followed by Pseudomonas aeruginosa (24.5%). Besides Pseudomonas, Acinetobacter spp. were the next common gram negative bacilli detected (8.3%) followed by Klebsiella, E. coli, Enterobacter and Alkaligenes in 2.6%, 0.8%, 0.8% and 0.5% cases respectively. The predominant fungal species were Aspergillus spp., in 36.1%, followed by Fusarium spp. in 26.4% cases. Overall susceptibility pattern in our study showed that gram positive bacteria were most susceptible to glycopeptides like vancomycin (80-100%) and fluoroquinolones (87-91%). The sensitivity pattern of gram negative organisms like Pseudomonas and Klebsiella towards fluoroquinolones ranged between 61% - 82%. S epidermidis was the most common bacteria isolated in postoperative and posttraumatic endophthalmitis, Pseudomonas aeruginosa was the most common bacterial isolated in posttraumatic endophthalmitisAmongst fungi Aspergillus was the most common organism.

Antibiotic use and resistance in emerging economies: a situation analysis for Viet Nam.

PubMed

Nguyen, Kinh Van; Thi Do, Nga Thuy; Chandna, Arjun; Nguyen, Trung Vu; Pham, Ca Van; Doan, Phuong Mai; Nguyen, An Quoc; Thi Nguyen, Chuc Kim; Larsson, Mattias; Escalante, Socorro; Olowokure, Babatunde; Laxminarayan, Ramanan; Gelband, Hellen; Horby, Peter; Thi Ngo, Ha Bich; Hoang, Mai Thanh; Farrar, Jeremy; Hien, Tran Tinh; Wertheim, Heiman F L

2013-12-10

Antimicrobial resistance is a major contemporary public health threat. Strategies to contain antimicrobial resistance have been comprehensively set forth, however in developing countries where the need for effective antimicrobials is greatest implementation has proved problematic. A better understanding of patterns and determinants of antibiotic use and resistance in emerging economies may permit more appropriately targeted interventions.Viet Nam, with a large population, high burden of infectious disease and relatively unrestricted access to medication, is an excellent case study of the difficulties faced by emerging economies in controlling antimicrobial resistance. Our working group conducted a situation analysis of the current patterns and determinants of antibiotic use and resistance in Viet Nam. International publications and local reports published between 1-1-1990 and 31-8-2012 were reviewed. All stakeholders analyzed the findings at a policy workshop and feasible recommendations were suggested to improve antibiotic use in Viet Nam.Here we report the results of our situation analysis focusing on: the healthcare system, drug regulation and supply; antibiotic resistance and infection control; and agricultural antibiotic use. Market reforms have improved healthcare access in Viet Nam and contributed to better health outcomes. However, increased accessibility has been accompanied by injudicious antibiotic use in hospitals and the community, with predictable escalation in bacterial resistance. Prescribing practices are poor and self-medication is common - often being the most affordable way to access healthcare. Many policies exist to regulate antibiotic use but enforcement is insufficient or lacking.Pneumococcal penicillin-resistance rates are the highest in Asia and carbapenem-resistant bacteria (notably NDM-1) have recently emerged. Hospital acquired infections, predominantly with multi-drug resistant Gram-negative organisms, place additional strain on limited resources. Widespread agricultural antibiotic use further propagates antimicrobial resistance. Future legislation regarding antibiotic access must alter incentives for purchasers and providers and ensure effective enforcement. The Ministry of Health recently initiated a national action plan and approved a multicenter health improvement project to strengthen national capacity for antimicrobial stewardship in Viet Nam. This analysis provided important input to these initiatives. Our methodologies and findings may be of use to others across the world tackling the growing threat of antibiotic resistance.

Empirical validation of guidelines for the management of pharyngitis in children and adults.

PubMed

McIsaac, Warren J; Kellner, James D; Aufricht, Peggy; Vanjaka, Anita; Low, Donald E

2004-04-07

Recent guidelines for management of pharyngitis vary in their recommendations concerning empirical antibiotic treatment and the need for laboratory confirmation of group A streptococcus (GAS). To assess the impact of guideline recommendations and alternative approaches on identification and treatment of GAS pharyngitis in children and adults. Throat cultures and rapid antigen tests were performed on 787 children and adults aged 3 to 69 years with acute sore throat attending a family medicine clinic in Calgary, Alberta, from September 1999 to August 2002. Recommendations from 2 guidelines (those of the Infectious Diseases Society of America and of the American College of Physicians-American Society of Internal Medicine/American Academy of Family Physicians/US Centers for Disease Control and Prevention) were compared with rapid testing alone, a clinical prediction rule (ie, the modified Centor score), and a criterion standard of treatment for positive throat culture results only. Sensitivity and specificity of each strategy for identifying GAS pharyngitis, total antibiotics recommended, and unnecessary antibiotic prescriptions. In children, sensitivity for streptococcal infection ranged from 85.8% (133/155; 95% confidence interval [CI], 79.3%-90.0%) for rapid testing to 100% for culturing all. In adults, sensitivity ranged from 76.7% (56/73; 95% CI, 65.4%-85.8%) for rapid testing without culture confirmation of negative results to 100% for culturing all. In children, specificity ranged from 90.3% (270/299; 95% CI, 86.4%-93.4%) for use of modified Centor score and throat culture to 100% for culturing all. In adults, specificity ranged from 43.8% (114/260; 95% CI, 37.7%-50.1%) for empirical treatment based on a modified Centor score of 3 or 4 to 100% for culturing all. Total antibiotic prescriptions were lowest with rapid testing (24.7% [194/787]; 95% CI, 21.7%-27.8%) and highest with empirical treatment of high-risk adults (45.7% [360/787]; 95% CI, 42.2%-49.3%), due to a high rate of unnecessary prescriptions in adults (43.8% [146/333]; 95% CI, 38.4%-49.4%). Guideline recommendations for the selective use of throat cultures but antibiotic treatment based only on positive rapid test or throat culture results can reduce unnecessary use of antibiotics for treatment of pharyngitis. However, empirical treatment of adults having a Centor score of 3 or 4 is associated with a high rate of unnecessary antibiotic use. In children, strategies incorporating throat culture or throat culture confirmation of negative rapid antigen test results are highly sensitive and specific. Throat culture of all adults or those selected on the basis of a clinical prediction rule had the highest sensitivity and specificity.

Treating Wisely: The Surgeon's Role in Antibiotic Stewardship.

PubMed

Leeds, Ira L; Fabrizio, Anne; Cosgrove, Sara E; Wick, Elizabeth C

2017-05-01

: Antibiotic resistance continues to receive national attention as a leading public health threat. In 2015, President Barack Obama proposed a National Action Plan to Combat Antibiotic-Resistant Bacteria to curb the rise of "superbugs," bacteria resistant to antibiotics of last resort. Whereas many antibiotics are prescribed appropriately to treat infections, there continue to be a large number of inappropriately prescribed antibiotics. Although much of the national attention with regards to stewardship has focused on primary care providers, there is a significant opportunity for surgeons to embrace this national imperative and improve our practices. Local quality improvement efforts suggest that antibiotic misuse for surgical disease is common. Opportunities exist as part of day-to-day surgical care as well as through surgeons' interactions with nonsurgeon colleagues and policy experts. This article discusses the scope of the antibiotic misuse in surgery for surgical patients, and provides immediate practice improvements and also advocacy efforts surgeons can take to address the threat. We believe that surgical antibiotic prescribing patterns frequently do not adhere to evidence-based practices; surgeons are in a position to mitigate their ill effects; and antibiotic stewardship should be a part of every surgeons' practice.

Effect of septoplasty and per-operative antibiotic prophylaxis on nasal flora.

PubMed

Karaman, E; Alimoglu, Y; Aygun, G; Kilic, E; Yagiz, C

2012-01-01

Septoplasty is one of the most commonly performed procedures in otolaryngology practice. Prophylactic use of antibiotics is controversial. Disruption of nasal flora may predispose individuals to infection. We investigated the effect of antibiotic prophylaxis and septoplasty on nasal flora. We included 115 consecutive patients who underwent septoplasty because of symptomatic nasal septal deviation. Patients were divided into study and control groups. Study patients received prophylactic parenteral sodium cefazoline twice a day beginning intra-operatively and while the nasal packing remained in the nose for 48 h, and expandable polyvinyl acetate (Merocel) packing covered with antibiotic ointment containing 0.2% nitrofurazone was inserted into each nostril at the end of the operation. Control patients received neither parenteral antibiotic prophylaxis nor antibiotic ointment around the Merocel packs. Both groups received oral prophylactic cefuroxime axetil for 5 d after nasal packing was removed. Nasal flora was determined pre-operatively, post-operatively when nasal packing was removed, and 3 mo after surgery. Study patients were compared to control patients at pack removal and 1 mo after surgery The effect of antibiotic use in septoplasty on nasal flora was as follows: Increased isolation rate of gram-positive rods (p = 0.007), decreased methicillin-sensitive coagulase-negative staphylococci (p = 0.002). Pre-operative and post-operative culture results at 3 mo were compared. The effect of septoplasty on nasal flora was as follows: Decreased coagulase-negative staphylococci (p = 0.05), decreased Klebsiella (p < 0.001), decreased gram-positive rods (p < 0.001), increased methicillin-sensitive Staphylococcus aureus (p < 0.001). Septoplasty increases S. aureus colonization and decreases normal flora. Antibiotics do not protect against S. aureus colonization and contribute to a decrease in normal flora. Antibiotics do not seem to confer benefit in terms of flora changes. Studies investigating flora changes with a longer follow-up should be conducted.

Fitness Trade-Offs in Competence Differentiation of Bacillus subtilis

PubMed Central

Yüksel, Melih; Power, Jeffrey J.; Ribbe, Jan; Volkmann, Thorsten; Maier, Berenike

2016-01-01

In the stationary phase, Bacillus subtilis differentiates stochastically and transiently into the state of competence for transformation (K-state). The latter is associated with growth arrest, and it is unclear how the ability to develop competence is stably maintained, despite its cost. To quantify the effect differentiation has on the competitive fitness of B. subtilis, we characterized the competition dynamics between strains with different probabilities of entering the K-state. The relative fitness decreased with increasing differentiation probability both during the stationary phase and during outgrowth. When exposed to antibiotics inhibiting cell wall synthesis, transcription, and translation, cells that differentiated into the K-state showed a selective advantage compared to differentiation-deficient bacteria; this benefit did not require transformation. Although beneficial, the K-state was not induced by sub-MIC concentrations of antibiotics. Increasing the differentiation probability beyond the wt level did not significantly affect the competition dynamics with transient antibiotic exposure. We conclude that the competition dynamics are very sensitive to the fraction of competent cells under benign conditions but less sensitive during antibiotic exposure, supporting the picture of stochastic differentiation as a fitness trade-off. PMID:27375604

Fitness Trade-Offs in Competence Differentiation of Bacillus subtilis.

PubMed

Yüksel, Melih; Power, Jeffrey J; Ribbe, Jan; Volkmann, Thorsten; Maier, Berenike

2016-01-01

In the stationary phase, Bacillus subtilis differentiates stochastically and transiently into the state of competence for transformation (K-state). The latter is associated with growth arrest, and it is unclear how the ability to develop competence is stably maintained, despite its cost. To quantify the effect differentiation has on the competitive fitness of B. subtilis, we characterized the competition dynamics between strains with different probabilities of entering the K-state. The relative fitness decreased with increasing differentiation probability both during the stationary phase and during outgrowth. When exposed to antibiotics inhibiting cell wall synthesis, transcription, and translation, cells that differentiated into the K-state showed a selective advantage compared to differentiation-deficient bacteria; this benefit did not require transformation. Although beneficial, the K-state was not induced by sub-MIC concentrations of antibiotics. Increasing the differentiation probability beyond the wt level did not significantly affect the competition dynamics with transient antibiotic exposure. We conclude that the competition dynamics are very sensitive to the fraction of competent cells under benign conditions but less sensitive during antibiotic exposure, supporting the picture of stochastic differentiation as a fitness trade-off.

Evaluation of effect of high frequency electromagnetic field on growth and antibiotic sensitivity of bacteria.

PubMed

Salmen, Saleh H; Alharbi, Sulaiman A; Faden, Asmaa A; Wainwright, M

2018-01-01

This study was aimed to evaluate the impact of high frequency electromagnetic fields (HF-EMF at 900 and 1800 MHz) on DNA, growth rate and antibiotic susceptibility of S. aureus , S. epidermidis , and P. aeruginosa . In this study, bacteria were exposed to 900 and 1800 MHz for 2 h and then inoculated to new medium when their growth rate and antibiotic susceptibility were evaluated. Results for the study of bacterial DNA unsuccessful to appearance any difference exposed and non-exposed S. aureus and S. epidermidis . Exposure of S. epidermidis and S. aureus to electromagnetic fields mostly produced no statistically significant decrease in bacterial growth, except for S. aureus when exposure to 900 MHz at 12 h. Exposure of P. aeruginosa to electromagnetic fields at 900 MHz however, lead to a significant reduction in growth rate, while 1800 MHz had insignificant effect. With the exception of S. aureus , treated with amoxicillin (30 µg) and exposed to electromagnetic fields, radiation treatment had no significant effect on bacterial sensitivity to antibiotics.

Present and future of prophylactic antibiotics for severe acute pancreatitis

PubMed Central

Jiang, Kun; Huang, Wei; Yang, Xiao-Nan; Xia, Qing

2012-01-01

AIM: To investigate the role of prophylactic antibiotics in the reduction of mortality of severe acute pancreatitis (SAP) patients, which is highly questioned by more and more randomized controlled trials (RCTs) and meta-analyses. METHODS: An updated meta-analysis was performed. RCTs comparing prophylactic antibiotics for SAP with control or placebo were included for meta-analysis. The mortality outcomes were pooled for estimation, and re-pooled estimation was performed by the sensitivity analysis of an ideal large-scale RCT. RESULTS: Currently available 11 RCTs were included. Subgroup analysis showed that there was significant reduction of mortality rate in the period before 2000, while no significant reduction in the period from 2000 [Risk Ratio, (RR) = 1.01, P = 0.98]. Funnel plot indicated that there might be apparent publication bias in the period before 2000. Sensitivity analysis showed that the RR of mortality rate ranged from 0.77 to 1.00 with a relatively narrow confidence interval (P < 0.05). However, the number needed to treat having a minor lower limit of the range (7-5096 patients) implied that certain SAP patients could still potentially prevent death by antibiotic prophylaxis. CONCLUSION: Current evidences do not support prophylactic antibiotics as a routine treatment for SAP, but the potentially benefited sub-population requires further investigations. PMID:22294832

Histopathology of valves in infective endocarditis, diagnostic criteria and treatment considerations.

PubMed

Brandão, Tatiana J D; Januario-da-Silva, Carolina A; Correia, Marcelo G; Zappa, Monica; Abrantes, Jaime A; Dantas, Angela M R; Golebiovski, Wilma; Barbosa, Giovanna Ianini F; Weksler, Clara; Lamas, Cristiane C

2017-04-01

Infective endocarditis (IE) is a severe disease. Pathogen isolation is fundamental so as to treat effectively and reduce morbidity and mortality. Blood and valve culture and histopathology (HP) are routinely employed for this purpose. Valve HP is the gold standard for diagnosis. To determine the sensitivity and specificity of clinical criteria for IE (the modified Duke and the St Thomas' minor modifications, STH) of blood and valve culture compared to valve HP, and to evaluate antibiotic treatment duration. Prospective case series of patients, from 2006 to 2014 with surgically treated IE. Statistical analysis was done by the R software. There were 136 clinically definite episodes of IE in 133 patients. Mean age ± SD was 43 ± 15.6 years and IE was left sided in 81.6 %. HP was definite in 96 valves examined, which were used as gold standard. Sensitivity of blood culture was 61 % (CI 0.51, 0.71) and of valve culture 15 % (CI 0.07, 0.26). The modified Duke criteria were 65 % (CI 0.55, 0.75) sensitive and 33 % specific, while the STH's sensitivity was 72 % (CI 0.61, 0.80) with similar specificity. In multivariate analysis and logistic regression, the only variable with statistical significance was duration of antibiotic therapy postoperatively. Valve HP had high sensitivity and valve culture low sensitivity in the diagnosis of IE. The STH's criteria were more sensitive than the modified Duke criteria. Valve HP should guide duration of postoperative antibiotic treatment.

The sensitivity of Bacillus subtilis to diverse antimicrobial compounds is influenced by Abh.

PubMed

Murray, Ewan J; Stanley-Wall, Nicola R

2010-12-01

Abh is a transition state regulator of Bacillus subtilis that controls biofilm formation and the production of several diverse antimicrobial compounds. Using a high-throughput non-biased technique, we show for the first time that Abh influences the sensitivity of B. subtilis to diverse antimicrobial compounds. Following up on these findings with a combination of classical genetics and antibiotic susceptibility assays, we demonstrate that Abh influences cellular processes such as the remodelling of the cell wall. We present data demonstrating that the extracytoplasmic function sigma factor σ(X) controls resistance to β-lactam antibiotics by activating abh transcription. Downstream from Abh, activation of slrR expression by Abh is responsible for controlling the sensitivity of B. subtilis to such antibiotics due to the role that SlrR plays in regulating autolysin biosynthesis. The abh mutant additionally exhibits increased resistance to aminoglycoside antimicrobials. We confirm that aminoglycoside killing of B. subtilis is likely to be caused by oxidative damage but rule out the possibility that the increased resistance of the abh mutant to aminoglycosides is due to a general increase in resistance to oxidative stress.

Rapid antibiotic-resistance predictions from genome sequence data for Staphylococcus aureus and Mycobacterium tuberculosis

PubMed Central

Bradley, Phelim; Gordon, N. Claire; Walker, Timothy M.; Dunn, Laura; Heys, Simon; Huang, Bill; Earle, Sarah; Pankhurst, Louise J.; Anson, Luke; de Cesare, Mariateresa; Piazza, Paolo; Votintseva, Antonina A.; Golubchik, Tanya; Wilson, Daniel J.; Wyllie, David H.; Diel, Roland; Niemann, Stefan; Feuerriegel, Silke; Kohl, Thomas A.; Ismail, Nazir; Omar, Shaheed V.; Smith, E. Grace; Buck, David; McVean, Gil; Walker, A. Sarah; Peto, Tim E. A.; Crook, Derrick W.; Iqbal, Zamin

2015-01-01

The rise of antibiotic-resistant bacteria has led to an urgent need for rapid detection of drug resistance in clinical samples, and improvements in global surveillance. Here we show how de Bruijn graph representation of bacterial diversity can be used to identify species and resistance profiles of clinical isolates. We implement this method for Staphylococcus aureus and Mycobacterium tuberculosis in a software package (‘Mykrobe predictor') that takes raw sequence data as input, and generates a clinician-friendly report within 3 minutes on a laptop. For S. aureus, the error rates of our method are comparable to gold-standard phenotypic methods, with sensitivity/specificity of 99.1%/99.6% across 12 antibiotics (using an independent validation set, n=470). For M. tuberculosis, our method predicts resistance with sensitivity/specificity of 82.6%/98.5% (independent validation set, n=1,609); sensitivity is lower here, probably because of limited understanding of the underlying genetic mechanisms. We give evidence that minor alleles improve detection of extremely drug-resistant strains, and demonstrate feasibility of the use of emerging single-molecule nanopore sequencing techniques for these purposes. PMID:26686880

Antibiotic failure mediated by a resistant subpopulation in Enterobacter cloacae

PubMed Central

Band, Victor I.; Crispell, Emily K.; Napier, Brooke A.; Herrera, Carmen M.; Tharp, Greg K.; Vavikolanu, Kranthi; Pohl, Jan; Read, Timothy D.; Bosinger, Steven E.; Trent, M. Stephen; Burd, Eileen M.; Weiss, David S.

2016-01-01

Antibiotic resistance is a major public health threat, further complicated by unexplained treatment failures caused by bacteria that appear antibiotic susceptible. We describe an Enterobacter cloacae isolate harbouring a minor subpopulation that is highly resistant to the last-line antibiotic colistin. This subpopulation was distinct from persisters, became predominant in colistin, returned to baseline after colistin removal and was dependent on the histidine kinase PhoQ. During murine infection, but in the absence of colistin, innate immune defences led to an increased frequency of the resistant subpopulation, leading to inefficacy of subsequent colistin therapy. An isolate with a lower-frequency colistin-resistant subpopulation similarly caused treatment failure but was misclassified as susceptible by current diagnostics once cultured outside the host. These data demonstrate the ability of low-frequency bacterial subpopulations to contribute to clinically relevant antibiotic resistance, elucidating an enigmatic cause of antibiotic treatment failure and highlighting the critical need for more sensitive diagnostics. PMID:27572838

Real-time detection of antibiotic activity by measuring nanometer-scale bacterial deformation.

PubMed

Iriya, Rafael; Syal, Karan; Jing, Wenwen; Mo, Manni; Yu, Hui; Haydel, Shelley E; Wang, Shaopeng; Tao, Nongjian

2017-12-01

Diagnosing antibiotic-resistant bacteria currently requires sensitive detection of phenotypic changes associated with antibiotic action on bacteria. Here, we present an optical imaging-based approach to quantify bacterial membrane deformation as a phenotypic feature in real-time with a nanometer scale (∼9  nm) detection limit. Using this approach, we found two types of antibiotic-induced membrane deformations in different bacterial strains: polymyxin B induced relatively uniform spatial deformation of Escherichia coli O157:H7 cells leading to change in cellular volume and ampicillin-induced localized spatial deformation leading to the formation of bulges or protrusions on uropathogenic E. coli CFT073 cells. We anticipate that the approach will contribute to understanding of antibiotic phenotypic effects on bacteria with a potential for applications in rapid antibiotic susceptibility testing. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

Hot Topics in Perioperative Antibiotics for Cataract Surgery.

PubMed

Kuklo, Patrycja; Grzybowski, Andrzej; Schwartz, Stephen G; Flynn, Harry W; Pathengay, Avinash

2017-01-01

Acute-onset postoperative endophthalmitis is an uncommon but potentially serious complication of cataract surgery. Since there are relatively few randomized clinical trials comparing the timing and administration of prophylactic antibiotics, there are wide variations in prevention practices around the world. Literature review. Antibiotics may be used before surgery, during surgery, or after surgery in an attempt to decrease the rates of endophthalmitis. Antibiotics may be delivered by various routes, including topical, subconjunctival, in the irrigating solution, or by bolus intracameral injection. Polymerase chain reaction and other DNA identification techniques for bacterial isolates and their antibiotic sensitivity profiles will play an important role in future management strategies. There is no consensus regarding the precise use of antibiotics in the perioperative period. Because of increased multidrug-resistant bacteria, evolving strategies are needed to address these issues. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

In the era of the 24 h laboratory, does communicating Gram stain results from blood cultures flagging positive outside of conventional working hours alter patient management?

PubMed

Moore, Jonathan S; Koerner, Roland J

2015-11-01

As laboratories move towards 24 h a day working patterns, we aim to evaluate if expediting the availability of provisional blood culture results outside of normal working hours would derive clinical benefit. 116 blood cultures flagging positive outside of conventional working hours (20:00-09:00) were studied. In each case, medical records were reviewed and cases discussed with clinicians to determine if earlier communication of results would have altered management and affected the outcome. Organisms were seen in 102/116 blood cultures. In total, 76/82 (92.7%) patients with cultures deemed to be significant were on an antibiotic. The isolate was sensitive to the prescribed antibiotic in 56/74 (76%) cases. Input from a microbiologist is likely to have altered management in 14 (13.7%) cases, but unlikely to have affected any outcomes. We found no compelling evidence that expediting the availability of Gram stain results from positive blood cultures alone improves patient outcome. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Incidence of multidrug-resistant, extensively drug-resistant and pan-drug-resistant bacteria in children hospitalized at Dr. Hasan Sadikin general hospital Bandung Indonesia

NASA Astrophysics Data System (ADS)

Adrizain, R.; Suryaningrat, F.; Alam, A.; Setiabudi, D.

2018-03-01

Antibiotic resistance has become a global issue, with 700,000 deaths attributable to multidrug-resistance (MDR) occurring each year. Centers for Disease Control and Prevention (CDC) show rapidly increasing rates of infection due to antibiotic-resistant bacteria. The aim of the study isto describe the incidence of MDR, extensively drug-resistant (XDR) and pan drug-resistant (PDR) in Enterococcus spp., Staphylococcus aureus, K. pneumonia, Acinetobacter baumanii, P. aeruginosin, and Enterobacter spp. (ESKAPE) pathogens in children admitted to Dr. Hasan Sadikin Hospital. All pediatric patients having blood culture drawn from January 2015 to December 2016 were retrospectively studied. Data include the number of drawn blood culture, number of positive results, type of bacteria, sensitivity pattern. International standard definitions for acquired resistance by ECDC and CDC was used as definitions for MDR, XDR and PDR bacteria. From January 2015 to December 2016, 299 from 2.542 (11.7%) blood culture was positive, with Staphylococcus aureus, Enterococcus spp., Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter spp., respectively 5, 6, 24, 5, 20 with total 60 (20%). The MDR and XDR pathogen found were 47 and 13 patients, respectively.

[Pulmonary nocardiasis with abscesses spreading to cerebrum, cerebellum and orbits].

PubMed

Borchers, M; von der Mülbe, B; Teikemeier, F; Theegarten, D

2006-05-12

A 71-year-old woman presented with suspected tuberculosis. She reported having productive coughs, unwanted weight loss and subfebrile temperature in the preceding 3 months. She was known to have chronic obstructive pulmonary disease treated with corticoids given systemically and by inhalation. She was a heavy smoker. Computed tomography revealed a left apical lung abscess. In the further course of the disease magnetic resonance imaging of the head demonstrated multiple abscesses in both cerebral hemispheres and an abscess, 3.4 cm in diameter, in the right side of the cerebellum, as well as a intra-orbital tumor on the right. Needle aspirate of the eyeball grew Nocardia farcinica. Over 3 weeks antimicrobial treatment was given with imipenem and amikacin, followed by oral cotrimoxazole for 12 months. The abscesses completely regressed and after 12 months no recurrence was demonstrated either radiologically or clinically. Although nocardiasis is rare in Germany it must be included in the differential diagnosis of pneumonia with abscesses. This is especially so if acid-fast bacilli are found. As the resistance pattern of N. farcinica to antibiotics varies, early treatment is essential with antibiotics to which it is sensitive.

Microbiology of tunnelled catheter-related infections in a multi-ethnic South-east Asian patient population.

PubMed

Teo, Boon Wee; Sau, Po Yi; Xu, Hui; Ma, Valerie; Vathsala, A; Lee, Evan J C

2011-01-01

Clinical practice guidelines recommend empiric antibiotic therapy for suspected tunnelled haemodialysis catheter-related infections (CRI), and the choice of antibiotics should be adjusted according to the local microbiological profile and antimicrobial sensitivities. We aim to describe the microbiology, antibiotic sensitivities, and clinical outcomes of CRI with tunnelled haemodialysis catheters in a multi-ethnic South-East Asian population. Using a prospective vascular access registry, we identified 99 patients who had catheters removed for suspected or confirmed CRI (50.5% male, mean age 56.9 years) from January 1, 2007, till May 2009. We retrospectively retrieved microbiology, mortality and echocardiography data from the hospital electronic databases. There were 115 removal-unique cultures that yielded 75.7% Gram-positive and 24.3% Gram-negative isolates (15 removals were polymicrobial). Organisms isolated were methicillin-resistant Staphylococcus aureus (MRSA) 28.6%, methicillin-sensitive S. aureus 26.5%, coagulase-negative staphylococci 21.4%, Pseudomonas aeruginosa 10.2%, and others. Out of 8 patients who died, 7 had MRSA. Risk factors associated with mortality were Chinese race (p = 0.03), MRSA infection (p < 0.001), and older age (p < 0.001). Gram-positive isolates accounted for most tunnelled CRI and MRSA was highly associated with death. In sick patients presenting with suspected CRI, the preferred empiric antibiotic regimen should include agents active against both MRSA and P. aeruginosa. Copyright © 2010 S. Karger AG, Basel.

Antibiotic prophylaxis among commercial sex workers in Cebu City, Philippines. Patterns of use and perceptions of efficacy.

PubMed

Abellanosa, I; Nichter, M

1996-01-01

This study describes the extent to which commercial sex workers (CSW) in Cebu City, Philippines perceive prophylactic antibiotic use to be an effective form of prevention for sexually transmitted diseases (STD) and human immunodeficiency virus (HIV), as well as the prevalence of this self-treatment practice. A survey instrument was developed and pretested after 3 months of intensive ethnographic research on STD and acquired immune deficiency syndrome (AIDS). A multistage sampling procedure was followed to ensure that a representative sample of CSW from four distinct work environments would be interviewed. Commercial sex workers registered at the Cebu City social hygiene clinic were sampled randomly from coded work establishment lists, and a convenience sample of unregistered freelance CSW was secured. In total, 200 CSW were interviewed. Of these 200 CSW, all were sexually active, but only 160 had been engaged actively in commercial sexual exchange the month before their interviews. Popular use of antibiotics as prophylaxis against STD is commonplace in the Philippines among CSW, with 38% reporting routine or occasional use and 31% reporting use in the last 2 weeks. Unregistered CSW are five times more likely to use prophylactic antibiotics than registered CSW, and they are seven times less likely to use condoms with 80% or more of their customers. They also have sex with three times as many customers. Use of prophylactic antibiotics by CSW offers them a false sense of security in a high-risk work environment. Self-treatment with low-dose prophylactic antibiotics provides no protection against STD, impedes STD screening efforts, and contributes to antibiotic resistance. An alarming percentage of CSW consider antibiotics a potential means of protecting themselves against AIDS. Public health interventions focusing on STD and AIDS in developing countries must address current patterns of prophylactic antibiotic use.

Phenotypic and genotypic characterisation of multiple antibiotic-resistant Staphylococcus aureus exposed to subinhibitory levels of oxacillin and levofloxacin.

PubMed

Jo, Ara; Ahn, Juhee

2016-07-29

The emergence and spread of multidrug resistant methicillin-resistant Staphylococcus aureus (MDR-MRSA) has serious health consequences in the presence of sub-MIC antibiotics. Therefore, this study was designed to evaluate β-lactamase activity, efflux activity, biofilm formation, and gene expression pattern in Staphylococcus aureus KACC 10778, S. aureus ATCC 15564, and S. aureus CCARM 3080 exposed to sublethal concentrations of levofloxacin and oxacillin. The decreased MICs were observed in S. aureus KACC and S. aureus ATCC when exposed to levofloxacin and oxacillin, while and S. aureus CCARM remained resistance to streptomycin (512 μg/mL) in the presence of levofloxacin and imipenem (>512 μg/mL) in the presence of oxacillin. The considerable increase in extracellular and membrane-bound β-lactamase activities was observed in S. aureus ATCC exposed to oxacillin (>26 μmol/min/mL). The antibiotic susceptibility of all strains exposed to EPIs (CCCP and PAβN) varied depending on the classes of antibiotics. The relative expression levels of adhesion-related genes (clfA, clfB, fnbA, fnnB, and icaD), efflux-related genes (norB, norC, and qacA/B), and enterotoxin gene (sec) were increased more than 5-fold in S. aureus CCARM. The eno and qacA/B genes were highly overexpressed by more than 12- and 9-folds, respectively, in S. aureus CCARM exposed to levofloxacin. The antibiotic susceptibility, lactamase activity, biofilm-forming ability, efflux activity, and gene expression pattern varied with the intrinsic antibiotic resistance of S. aureus KACC, S. aureus ATCC, and S. aureus CCARM exposed to levofloxacin and oxacillin. This study would provide useful information for better understating of combination therapy related to antibiotic resistance mechanisms and open the door for designing effective antibiotic treatment protocols to prevent excessive use of antibiotics in clinical practice.

[Paths to the professional and responsible use of antibiotics].

PubMed

Abele-Horn, Marianne; Pantke, Ellen; Eckmanns, Tim

2018-05-01

Germany's position on prescribing antibiotics is among the lower third in Europe. There are some countries that prescribe remarkably fewer antibiotics. In Germany, the number of out-patient antibiotic prescriptions is too high for patients with low-grade infections and non-bacterial infections. Often, broad-spectrum antibiotics are prescribed instead of narrow-spectrum antibiotics. For in-patients, perioperative prophylaxis is given for too long.In this article, different ways to reduce antibiotic prescriptions are introduced. Recommendations are given to improve the quality of therapy, implementation of diagnostics and scores, as well as information for physicians and patients.In this regard, an unsystematic literature search was done.To optimise the quality of prescribing, antibiotic checklists should be used. The important initial questions are if there is a bacterial infection and if antibiotic therapy is necessary. To apply diagnostics correctly is essential. Antibiotic use can be shortened or in some cases totally omitted if point-of-care tests (POCTs) are applied correctly. Species identification and resistance testing are essential for quality assurance. S3-guidelines are central for modern evidence-based medicine. Another key factor is good communication within the team and with patients. All measurements, like the application of POCTs, back-up prescribing, and prescribing an antibiotic, have to be communicated in a clear and sensitive way.

Patient Attitudes and Beliefs and Provider Practices Regarding Antibiotic Use for Acute Respiratory Tract Infections in Minya, Egypt

PubMed Central

Kandeel, Amr; El-Shoubary, Waleed; Hicks, Lauri A.; Abdel Fattah, Mohamed; Dooling, Kathleen L.; Lohiniva, Anna Leena; Ragab, Omnia; Galal, Ramy; Talaat, Maha

2014-01-01

The inappropriate use of antibiotics in the community is one of the major causes of antimicrobial resistance. This study aimed to explore the physician prescribing pattern of antibiotics for acute respiratory infections (ARIs) and to explore the knowledge, attitudes, and practices of patients regarding antibiotic use for ARIs. The study was conducted in Upper Egypt and used quantitative and qualitative research techniques. Eligible patients exiting outpatient clinics with ARIs were invited to participate in the study. A qualitative study was conducted through 20 focus group discussions. Out of 350 encounters for patients with various ARIs, 292 (83%) had been prescribed at least one antibiotic. Factors significantly associated with antibiotic prescribing for adults included patient preference that an antibiotic be prescribed. For children younger than 18, presentation with fever, cough, loss of appetite, and sore throat, along with the caregiver’s antibiotic preference, were associated with an antibiotic prescription. Several misconceptions regarding antibiotic use among community members were stated, such as the strong belief of the curing and prophylactic power of antibiotics for the common cold. Interventions to promote proper antibiotic use for ARIs need to be piloted, targeting both physicians and the public. Educational programs for physicians and campaigns to raise public awareness regarding proper antibiotic use for ARIs need to be developed. PMID:27025759

LONG-TERM STARVATION-INDUCED LOSS OF APPARENT ANTIBIOTIC RESISTANCE IN CELLS CONTAINING THE PLASMID PSA

EPA Science Inventory

Escherichia coli, Pseudomonas fluorescens, and a Pseudomonas sp. strain 133B containing the pSa plasmid were starved in well water for up to 523 days. There were two patterns of apparent antibiotic resistance loss observed. In Pseudomonas sp. strain 133B, there was no apparent lo...

Antibiotic susceptibility of enterococci isolated from traditional fermented meat products.

PubMed

Barbosa, J; Ferreira, V; Teixeira, P

2009-08-01

Antibiotic susceptibility was evaluated for 182 Enterococcus spp. isolated from Alheira, Chouriça de Vinhais and Salpicão de Vinhais, fermented meat products produced in the North of Portugal. Previously, a choice was made from a group of 1060 isolates, using phenotypic and genotypic tests. From these, 76 were previously identified as Enterococcus faecalis, 44 as Enterococcus faecium, one as Enterococcus casseliflavus and 61 as Enteroccocus spp. In order to encompass several of the known chemical and functional classes of antibiotics, resistance to ampicillin, penicillin G, ciprofloxacin, chloramphenicol, erythromycin, nitrofurantoin, rifampicin, tetracycline and vancomycin was evaluated. All the isolates were sensitive to antibiotics of clinical importance, such as penicillins and vancomycin. Some differences in Minimal Inhibitory Concentrations (MICs) of antibiotics, could be associated with the enterococcal species.

Association of metal tolerance with multiple antibiotic resistance of bacteria isolated from drinking water.

PubMed Central

Calomiris, J J; Armstrong, J L; Seidler, R J

1984-01-01

Bacterial isolates from the drinking water system of an Oregon coastal community were examined to assess the association of metal tolerance with multiple antibiotic resistance. Positive correlations between tolerance to high levels of Cu2+, Pb2+, and Zn2+ and multiple antibiotic resistance were noted among bacteria from distribution waters but not among bacteria from raw waters. Tolerances to higher levels of Al3+ and Sn2+ were demonstrated more often by raw water isolates which were not typically multiple antibiotic resistant. A similar incidence of tolerance to Cd2+ was demonstrated by isolates of both water types and was not associated with multiple antibiotic resistance. These results suggest that simultaneous selection phenomena occurred in distribution water for bacteria which exhibited unique patterns of tolerance to Cu2+, Pb2+, and Zn2+ and antibiotic resistance. PMID:6742841

Mesosomes are a definite event in antibiotic-treated Staphylococcus aureus ATCC 25923.

PubMed

Santhana Raj, L; Hing, H L; Baharudin, Omar; Teh Hamidah, Z; Aida Suhana, R; Nor Asiha, C P; Vimala, B; Paramsarvaran, S; Sumarni, G; Hanjeet, K

2007-06-01

Mesosomes of Staphylococcus aureus ATCC 25923 treated with antibiotics were examined morphologically under the electron microscope. The Transmission Electron Microscope Rapid Method was used to eliminate the artifacts due to sample processing. Mesosomes were seen in all the antibiotic treated bacteria and not in the control group. The main factor that contributes to the formation of mesosomes in the bacteria was the mode of action of the antibiotics. The continuous cytoplasmic membrane with infolding (mesosomes) as in the S. aureus ATCC 25923 is therefore confirmed as a definite pattern of membrane organization in gram positive bacteria assaulted by amikacin, gentamicin, ciprofloxacin, vancomycin and oxacillin antibiotics. Our preliminary results show oxacillin and vancomycin treated bacteria seemed to have deeper and more mesosomes than those treated with amikacin, gentamicin and ciprofloxacin. Further research is needed to ascertain whether the deep invagination and the number of mesosomes formed is associated with the types of antibiotic used.

Prescribing Patterns in Outpatient Clinics of Township Hospitals in China: A Comparative Study before and after the 2009 Health System Reform.

PubMed

Ding, Ding; Pan, Qingxia; Shan, Linghan; Liu, Chaojie; Gao, Lijun; Hao, Yanhua; Song, Jian; Ning, Ning; Cui, Yu; Li, Ye; Qi, Xinye; Liang, Chao; Wu, Qunhong; Liu, Guoxiang

2016-07-05

China introduced a series of health reforms in 2009, including a national essential medicines policy and a medical insurance system for primary care institutions. This study aimed to determine the changing prescribing patterns associated with those reforms in township hospitals. A multi-stage stratified random cluster sampling method was adopted to identify 29 township hospitals from six counties in three provinces. A total of 2899 prescriptions were collected from the participating township hospitals using a systematic random sampling strategy. Seven prescribing indicators were calculated and compared between 2008 and 2013, assessing use of medicines (antibiotics and adrenal corticosteroids) and polypharmacy, administration route of medicines (injections), and affordability of medicines. Significant changes in prescribing patterns were found. The average number of medicines and costs per-prescription dropped by about 50%. The percentage of prescriptions requiring antibiotics declined from 54% to 38%. The percentage of prescriptions requiring adrenal corticosteroid declined from 14% to 4%. The percentage of prescriptions requiring injections declined from 54% to 25%. Despite similar changing patterns, significant regional differences were observed. Significant changes in prescribing patterns are evident in township hospitals in China. Overprescription of antibiotics, injections and adrenal corticosteroids has been reduced. However, salient regional disparities still exist. Further studies are needed to determine potential shifts in the risk of the inappropriate use of medicines from primary care settings to metropolitan hospitals.

Evolution of antibiotic resistance is linked to any genetic mechanism affecting bacterial duration of carriage

PubMed Central

Lehtinen, Sonja; Blanquart, François; Croucher, Nicholas J.; Turner, Paul; Lipsitch, Marc; Fraser, Christophe

2017-01-01

Understanding how changes in antibiotic consumption affect the prevalence of antibiotic resistance in bacterial pathogens is important for public health. In a number of bacterial species, including Streptococcus pneumoniae, the prevalence of resistance has remained relatively stable despite prolonged selection pressure from antibiotics. The evolutionary processes allowing the robust coexistence of antibiotic sensitive and resistant strains are not fully understood. While allelic diversity can be maintained at a locus by direct balancing selection, there is no evidence for such selection acting in the case of resistance. In this work, we propose a mechanism for maintaining coexistence at the resistance locus: linkage to a second locus that is under balancing selection and that modulates the fitness effect of resistance. We show that duration of carriage plays such a role, with long duration of carriage increasing the fitness advantage gained from resistance. We therefore predict that resistance will be more common in strains with a long duration of carriage and that mechanisms maintaining diversity in duration of carriage will also maintain diversity in antibiotic resistance. We test these predictions in S. pneumoniae and find that the duration of carriage of a serotype is indeed positively correlated with the prevalence of resistance in that serotype. These findings suggest heterogeneity in duration of carriage is a partial explanation for the coexistence of sensitive and resistant strains and that factors determining bacterial duration of carriage will also affect the prevalence of resistance. PMID:28096340

Nordihydroguaiaretic acid enhances the activities of aminoglycosides against methicillin- sensitive and resistant Staphylococcus aureus in vitro and in vivo.

PubMed

Cunningham-Oakes, Edward; Soren, Odel; Moussa, Caroline; Rathor, Getika; Liu, Yingjun; Coates, Anthony; Hu, Yanmin

2015-01-01

Infections caused by methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) are prevalent. MRSA infections are difficult to treat and there are no new classes of antibiotics produced to the market to treat infections caused by the resistant bacteria. Therefore, using antibiotic enhancers to rescue existing classes of antibiotics is an attractive strategy. Nordihydroguaiaretic acid (NDGA) is an antioxidant compound found in extracts from plant Larrea Tridentata. It exhibits antimicrobial activity and may target bacterial cell membrane. Combination efficacies of NDGA with many classes of antibiotics were examined by chequerboard method against 200 clinical isolates of MRSA and MSSA. NDGA in combination with gentamicin, neomycin, and tobramycin was examined by time-kill assays. The synergistic combinations of NDGA and aminoglycosides were tested in vivo using a murine skin infection model. Calculations of the fractional inhibitory concentration index (FICI) showed that NDGA when combined with gentamicin, neomycin, or tobramycin displayed synergistic activities in more than 97% of MSSA and MRSA, respectively. Time kill analysis demonstrated that NDGA significantly augmented the activities of these aminoglycosides against MRSA and MSSA in vitro and in murine skin infection model. The enhanced activity of NDGA resides on its ability to damage bacterial cell membrane leading to accumulation of the antibiotics inside bacterial cells. We demonstrated that NDGA strongly revived the therapeutic potencies of aminoglycosides in vitro and in vivo. This combinational strategy could contribute major clinical implications to treat antibiotic resistant bacterial infections.

Long-term exposure to spaceflight conditions affects bacterial response to antibiotics.

PubMed

Juergensmeyer, M A; Juergensmeyer, E A; Guikema, J A

1999-01-01

Bacteria exposed to the spaceflight environment have been shown to have an increased growth rate and an increased resistance to antibiotics. The mechanism of resistance has not yet been identified, as the resistance is quickly lost upon return to Earth. To more fully characterize the spaceflight-induced resistance to antibiotics, 4 species of bacteria were exposed to microgravity for 4 months on the Space Station MIR. Upon return to Earth, these cultures were challenged with a suite of 12 antibiotics of varying modes of action. In contrast to reports from short-term space flights, we find that long-term exposure to microgravity causes bacteria to become more susceptible to most, but not all, antibiotics. Each species responds differently to the suite of antibiotics, frequently becoming less resistant, but occasionally more resistant to the antibiotic. A pattern enabling prediction of response is not yet discernible. While contradicting the results from short-term pure culture research, this experiment confirms results from astronaut and cosmonaut skin flora samples.

Molecular epidemiology of antibiotic resistance of Salmonella enteritidis during a 7-year period in Greece.

PubMed Central

Tassios, P T; Markogiannakis, A; Vatopoulos, A C; Katsanikou, E; Velonakis, E N; Kourea-Kremastinou, J; Legakis, N J

1997-01-01

A significant increase in the frequency of isolation of Salmonella enteritidis has been observed during recent years in Greece, parallelled by an increasing rate of resistance of this organism to antibiotics. A substantial proportion of ampicillin- and doxycycline-resistant isolates exhibited cross-resistance to drugs of other classes, such as sulfonamides and streptomycin. Isolates of human origin were overall less resistant than those of animal or food-feed origin. Indeed, strains associated with animal infections were characterized by the highest rates of resistance to several antibiotics. These phenotypic data were correlated with genotypic information concerning two distinct populations: isolates from all sources that were resistant only to ampicillin, the drug toward which resistance rates were highest, and a control group of sensitive isolates. Ampicillin resistance was due to a 34-MDa conjugative plasmid. DNA fingerprinting by macrorestriction of genomic DNA revealed two types, A and B, common to both ampicillin-resistant and -sensitive strains, with 80 to 90% of strains being of type A. However, a third type, C, was specific for the sensitive population, representing 17% of those strains. Therefore, although the majority of resistant isolates were genetically related to sensitive ones, there existed a susceptible clone which had not acquired any resistance traits. PMID:9163436

Electromagnetic irradiation of Enterococcus hirae at low-intensity 51.8- and 53.0-GHz frequencies: changes in bacterial cell membrane properties and enhanced antibiotics effects.

PubMed

Torgomyan, Heghine; Ohanyan, Vahe; Blbulyan, Syuzanna; Kalantaryan, Vitaly; Trchounian, Armen

2012-04-01

Exposure to electromagnetic irradiation (EMI) of 51.8 and 53.0 GHz and low intensity (flux capacity of 0.06 mW cm(-2) ) for 1 h markedly decreased the energy-dependent H(+) and K(+) transport across membranes of Enterococcus hirae ATCC 9790. After EMI, there was also a significant decrease of overall and N,N'-dicyclohexylcarbodiimide (DCCD)-sensitive ATPase activity of the membrane vesicles. These measures were considerably lower at 53.0 GHz. EMI in combination with different antibiotics, such as ceftriaxone and kanamycin at their minimal inhibitory concentrations (100 and 200 μM, respectively), enhanced bacterial cell growth and altered their membrane transport properties. Total H(+) efflux was most sensitive to ceftriaxone but DCCD-inhibited H(+) efflux and total K(+) influx were sensitive to kanamycin. The results indicate that cell membrane proteins could be a target in the action of EMI and enhanced antibacterial effects in combination with antibiotics. The DCCD-sensitive F(0) F(1) -ATPase or this ATPase in combination with K(+) uptake protein probably plays a key role in these effects. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Trans-Cinnamaldehyde and Eugenol Increase Acinetobacter baumannii Sensitivity to Beta-Lactam Antibiotics.

PubMed

Karumathil, Deepti P; Nair, Meera Surendran; Gaffney, James; Kollanoor-Johny, Anup; Venkitanarayanan, Kumar

2018-01-01

Multi-drug resistant (MDR) Acinetobacter baumannii is a major nosocomial pathogen causing a wide range of clinical conditions with significant mortality rates. A. baumannii strains are equipped with a multitude of antibiotic resistance mechanisms, rendering them resistant to most of the currently available antibiotics. Thus, there is a critical need to explore novel strategies for controlling antibiotic resistance in A. baumannii . This study investigated the efficacy of two food-grade, plant-derived antimicrobials (PDAs), namely trans -cinnamaldehyde (TC) and eugenol (EG) in decreasing A. baumannii 's resistance to seven β-lactam antibiotics, including ampicillin, methicillin, meropenem, penicillin, aztreonam, amoxicillin, and piperacillin. Two MDR A. baumannii isolates (ATCC 17978 and AB 251847) were separately cultured in tryptic soy broth (∼6 log CFU/ml) containing the minimum inhibitory concentration (MIC) of TC or EG with or without the MIC of each antibiotic at 37°C for 18 h. A. baumannii strains not exposed to the PDAs or antibiotics served as controls. Following incubation, A. baumannii counts were determined by broth dilution assay. In addition, the effect of PDAs on the permeability of outer membrane and efflux pumps in A. baumannii was measured. Further, the effect of TC and EG on the expression of A. baumannii genes encoding resistance to β-lactam antibiotics ( blaP ), efflux pumps ( adeABC ), and multi-drug resistant protein ( mdrp ) was studied using real-time quantitative PCR (RT-qPCR). The experiment was replicated three times with duplicate samples of each treatment and control. The results from broth dilution assay indicated that both TC and EG in combination with antibiotics increased the sensitivity of A. baumannii to all the tested antibiotics ( P < 0.05). The two PDAs inhibited the function of A. baumannii efflux pump, (AdeABC), but did not increase the permeability of its outer membrane. Moreover, RT-qPCR data revealed that TC and EG down-regulated the expression of majority of the genes associated with β-lactam antibiotic resistance, especially blaP and adeABC ( P < 0.05). The results suggest that TC and EG could potentially be used along with β-lactam antibiotics for controlling MDR A. baumannii infections; however, their clinical significance needs to be determined using in vivo studies.

Functional and Molecular Surveillance of Helicobacter pylori Antibiotic Resistance in Kuala Lumpur

PubMed Central

Teh, Xinsheng; Khosravi, Yalda; Lee, Woon Ching; Leow, Alex Hwong Ruey; Loke, Mun Fai; Vadivelu, Jamuna; Goh, Khean Lee

2014-01-01

Background Helicobacter pylori is the etiological agent for diseases ranging from chronic gastritis and peptic ulcer disease to gastric adenocarcinoma and primary gastric B-cell lymphoma. Emergence of resistance to antibiotics possesses a challenge to the effort to eradicate H. pylori using conventional antibiotic-based therapies. The molecular mechanisms that contribute to the resistance of these strains have yet to be identified and are important for understanding the evolutional pattern and selective pressure imposed by the environment. Methods and Findings H. pylori was isolated from 102 patients diagnosed with gastrointestinal diseases, who underwent endoscopy at University Malaya Medical Centre (UMMC). The isolates were tested for their susceptibility on eleven antibiotics using Etest. Based on susceptibility test, 32.3% of the isolates were found to have primary metronidazole resistance; followed by clarithromycin (6.8%) and fluoroquinolones (6.8%). To further investigate the resistant strains, mutational patterns of gene rdxA, frxA, gyrA, gyrB, and 23S rRNA were studied. Consistent with the previous reports, metronidazole resistance was prevalent in the local population. However, clarithromycin, fluoroquinolone and multi-drug resistance were shown to be emerging. Molecular patterns correlated well with phenotypic data. Interestingly, multi-drug resistant (MDR) strains were found to be associated with higher minimum inhibitory concentration (MIC) than their single-drug resistant (SDR) counterparts. Most importantly, clarithromycin-resistant strains were suggested to have a higher incidence for developing multi-drug resistance. Conclusion Data from this study highlighted the urgency to monitor closely the prevalence of antibiotic resistance in the Malaysian population; especially that of clarithromycin and multi-drug resistance. Further study is needed to understand the molecular association between clarithromycin resistance and multi-drug resistance in H. pylori. The report serves a reminder that a strict antibiotic usage policy is needed in Malaysia and other developing countries (especially those where H. pylori prevalence remained high). PMID:25003707

Susceptibility patterns of Staphylococcus aureus biofilms in diabetic foot infections.

PubMed

Mottola, Carla; Matias, Carina S; Mendes, João J; Melo-Cristino, José; Tavares, Luís; Cavaco-Silva, Patrícia; Oliveira, Manuela

2016-06-23

Foot infections are a major cause of morbidity in people with diabetes and the most common cause of diabetes-related hospitalization and lower extremity amputation. Staphylococcus aureus is by far the most frequent species isolated from these infections. In particular, methicillin-resistant S. aureus (MRSA) has emerged as a major clinical and epidemiological problem in hospitals. MRSA strains have the ability to be resistant to most β-lactam antibiotics, but also to a wide range of other antimicrobials, making infections difficult to manage and very costly to treat. To date, there are two fifth-generation cephalosporins generally efficacious against MRSA, ceftaroline and ceftobripole, sharing a similar spectrum. Biofilm formation is one of the most important virulence traits of S. aureus. Biofilm growth plays an important role during infection by providing defence against several antagonistic mechanisms. In this study, we analysed the antimicrobial susceptibility patterns of biofilm-producing S. aureus strains isolated from diabetic foot infections. The antibiotic minimum inhibitory concentration (MIC) was determined for ten antimicrobial compounds, along with the minimum biofilm inhibitory concentration (MBIC) and minimum biofilm eradication concentration (MBEC), followed by PCR identification of genetic determinants of biofilm production and antimicrobial resistance. Results demonstrate that very high concentrations of the most used antibiotics in treating diabetic foot infections (DFI) are required to inhibit S. aureus biofilms in vitro, which may explain why monotherapy with these agents frequently fails to eradicate biofilm infections. In fact, biofilms were resistant to antibiotics at concentrations 10-1000 times greater than the ones required to kill free-living or planktonic cells. The only antibiotics able to inhibit biofilm eradication on 50 % of isolates were ceftaroline and gentamicin. The results suggest that the antibiotic susceptibility patterns cannot be applied to biofilm established infections. Selection of antimicrobial therapy is a critical step in DFI and should aim at overcoming biofilm disease in order to optimize the outcomes of this complex pathology.

The drinking water treatment process as a potential source of affecting the bacterial antibiotic resistance.

PubMed

Bai, Xiaohui; Ma, Xiaolin; Xu, Fengming; Li, Jing; Zhang, Hang; Xiao, Xiang

2015-11-15

Two waterworks, with source water derived from the Huangpu or Yangtze River in Shanghai, were investigated, and the effluents were plate-screened for antibiotic-resistant bacteria (ARB) using five antibiotics: ampicillin (AMP), kanamycin (KAN), rifampicin (RFP), chloramphenicol (CM) and streptomycin (STR). The influence of water treatment procedures on the bacterial antibiotic resistance rate and the changes that bacteria underwent when exposed to the five antibiotics at concentration levels ranging from 1 to 100 μg/mL were studied. Multi-drug resistance was also analyzed using drug sensitivity tests. The results indicated that bacteria derived from water treatment plant effluent that used the Huangpu River rather than the Yangtze River as source water exhibited higher antibiotic resistance rates against AMP, STR, RFP and CM but lower antibiotic resistance rates against KAN. When the antibiotic concentration levels ranged from 1 to 10 μg/mL, the antibiotic resistance rates of the bacteria in the water increased as water treatment progressed. Biological activated carbon (BAC) filtration played a key role in increasing the antibiotic resistance rate of bacteria. Chloramine disinfection can enhance antibiotic resistance. Among the isolated ARB, 75% were resistant to multiple antibiotics. Ozone oxidation, BAC filtration and chloramine disinfection can greatly affect the relative abundance of bacteria in the community. Copyright © 2015 Elsevier B.V. All rights reserved.

Detection of antibiotic resistance is essential for gonorrhoea point-of-care testing: a mathematical modelling study.

PubMed

Fingerhuth, Stephanie M; Low, Nicola; Bonhoeffer, Sebastian; Althaus, Christian L

2017-07-26

Antibiotic resistance is threatening to make gonorrhoea untreatable. Point-of-care (POC) tests that detect resistance promise individually tailored treatment, but might lead to more treatment and higher levels of resistance. We investigate the impact of POC tests on antibiotic-resistant gonorrhoea. We used data about the prevalence and incidence of gonorrhoea in men who have sex with men (MSM) and heterosexual men and women (HMW) to calibrate a mathematical gonorrhoea transmission model. With this model, we simulated four clinical pathways for the diagnosis and treatment of gonorrhoea: POC test with (POC+R) and without (POC-R) resistance detection, culture and nucleic acid amplification tests (NAATs). We calculated the proportion of resistant infections and cases averted after 5 years, and compared how fast resistant infections spread in the populations. The proportion of resistant infections after 30 years is lowest for POC+R (median MSM: 0.18%, HMW: 0.12%), and increases for culture (MSM: 1.19%, HMW: 0.13%), NAAT (MSM: 100%, HMW: 99.27%), and POC-R (MSM: 100%, HMW: 99.73%). Per 100 000 persons, NAAT leads to 36 366 (median MSM) and 1228 (median HMW) observed cases after 5 years. Compared with NAAT, POC+R averts more cases after 5 years (median MSM: 3353, HMW: 118). POC tests that detect resistance with intermediate sensitivity slow down resistance spread more than NAAT. POC tests with very high sensitivity for the detection of resistance are needed to slow down resistance spread more than by using culture. POC with high sensitivity to detect antibiotic resistance can keep gonorrhoea treatable longer than culture or NAAT. POC tests without reliable resistance detection should not be introduced because they can accelerate the spread of antibiotic-resistant gonorrhoea.

Fluorescent aptasensor for antibiotic detection using magnetic bead composites coated with gold nanoparticles and a nicking enzyme.

PubMed

Luo, Zewei; Wang, Yimin; Lu, Xiaoyong; Chen, Junman; Wei, Fujing; Huang, Zhijun; Zhou, Chen; Duan, Yixiang

2017-09-01

Antibiotic abuse has been bringing serious pollution in water, which is closely related to human health. It is desirable to develop a new strategy for antibiotic detection. To address this problem, a sensitive fluorescent aptasensor for antibiotic detection was developed by utilizing gold nanoparticles modified magnetic bead composites (AuNPs/MBs) and nicking enzyme. AuNPs/MBs were synthesized with the help of polyethylenimine (PEI). The prepared AuNPs/MBs acted as dual-functional scaffolds that owned excellent magnetic separation capacity and strong covalent bio-conjugation. The non-specifically absorbed aptamers in AuNPs/MBs were less than that in MBs. Hence, the fluorescent aptasensor based on AuNPs/MBs show a better signal to background ratio than that based on carboxyl modified magnetic beads (MBs). In this work, ampicillin was employed as a model analyte. In the presence of ampicillin, the specific binding between ampicillin and aptamer induced structure-switching that led to the release of partial complementary DNA (cDNA) of aptamer. Then, the released cDNA initiated the cycle of nicking enzyme assisted signal amplification (NEASA). Therefore, a large amount of taqman probes were cleaved and fluorescence signal was amplified. The prepared fluorescent aptasensor bring sensitive detection in range of 0.1-100 ng mL -1 with the limit of detection of 0.07 ng mL -1 . Furthermore, this aptasensor was also successfully applied in real sample detection with acceptable accuracy. The fluorescent aptasensor provides a promising method for efficient, rapid and sensitive antibiotic detection. Copyright © 2017 Elsevier B.V. All rights reserved.

Receptor-based screening assays for the detection of antibiotics residues - A review.

PubMed

Ahmed, Saeed; Ning, Jianan; Cheng, Guyue; Ahmad, Ijaz; Li, Jun; Mingyue, Liu; Qu, Wei; Iqbal, Mujahid; Shabbir, M A B; Yuan, Zonghui

2017-05-01

Consumer and regulatory agencies have a high concern to antibiotic residues in food producing animals, so appropriate screening assays of fast, sensitive, low cost, and easy sample preparation for the identification of these residues are essential for the food-safety insurance. Great efforts in the development of a high-throughput antibiotic screening assay have been made in recent years. Concerning the screening of antibiotic residue, this review elaborate an overview on the availability, advancement and applicability of antibiotic receptor based screening assays for the safety assessment of antibiotics usage (i.e. radio receptor assay, enzyme labeling assays, colloidal gold receptor assay, enzyme colorimetry assay and biosensor assay). This manuscript also tries to shed a light on the selection, preparation and future perspective of receptor protein for antibiotic residue detection. These assays have been introduced for the screening of numerous food samples. Receptor based screening technology for antibiotic detection has high accuracy. It has been concluded that at the same time, it can detect a class of drugs for certain receptor, and realize the multi-residue detection. These assays offer fast, easy and precise detection of antibiotics. Copyright © 2017 Elsevier B.V. All rights reserved.

Enhancement of antibiotic effect via gold:silver-alloy nanoparticles

NASA Astrophysics Data System (ADS)

dos Santos, Margarida Moreira; Queiroz, Margarida João; Baptista, Pedro V.

2012-05-01

A strategy for the development of novel antimicrobials is to combine the stability and pleiotropic effects of inorganic compounds with the specificity and efficiency of organic compounds, such as antibiotics. Here we report on the use of gold:silver-alloy (Au:Ag-alloy) nanoparticles, obtained via a single-step citrate co-reduction method, combined to conventional antibiotics to enhance their antimicrobial effect on bacteria. Addition of the alloy nanoparticles considerably decreased the dose of antibiotic necessary to show antimicrobial effect, both for bacterial cells growing in rich medium in suspension and for bacterial cells resting in a physiological buffer on a humid cellulose surface. The observed effect was more pronounced than the sum of the individual effects of the nanoparticles and antibiotic. We demonstrate the enhancement effect of Au:Ag-alloy nanoparticles with a size distribution of 32.5 ± 7.5 nm mean diameter on the antimicrobial effect of (i) kanamycin on Escherichia coli (Gram-negative bacterium), and (ii) a β-lactam antibiotic on both a sensitive and resistant strain of Staphylococcus aureus (Gram-positive bacterium). Together, these results may pave the way for the combined use of nanoparticle-antibiotic conjugates towards decreasing antibiotic resistance currently observed for certain bacteria and conventional antibiotics.

Surface enhanced Raman spectroscopy for urinary tract infection diagnosis and antibiogram

NASA Astrophysics Data System (ADS)

Kastanos, Evdokia; Hadjigeorgiou, Katerina; Kyriakides, Alexandros; Pitris, Constantinos

2010-02-01

Urinary tract infection diagnosis and antibiogram require a minimum of 48 hours using standard laboratory practice. This long waiting period contributes to an increase in recurrent infections, rising health care costs, and a growing number of bacterial strains developing resistance to antibiotics. In this work, Surface Enhanced Raman Spectroscopy (SERS) was used as a novel method for classifying bacteria and determining their antibiogram. Five species of bacteria were classified with > 90% accuracy using their SERS spectra and a classification algorithm involving novel feature extraction and discriminant analysis. Antibiotic resistance or sensitivity was determined after just a two-hour exposure of bacteria to ciprofloxacin (sensitive) and amoxicillin (resistant) and analysis of their SERS spectra. These results can become the basis for the development of a novel method that would provide same day diagnosis and selection of the most appropriate antibiotic for most effective treatment of a urinary tract infection.

[Sensitivity of clinical Proteus strains to antibiotics and their combinations].

PubMed

Sheina, E P; Arutcheva, A A

1978-05-01

In 1976 isolation of Proteus from wounds of patients with various purulent processes amounted to 14.5 per cent. Serotypes 0-10, 0-3 and H-3 predominated among the isolates. Sensitivity of 35 clinical strains of Proteus to 10 antibiotics, furagin and nevigramone was studied by the method of serial dilutions in liquid media. All the isolates were highly resistant to the antibiotics except gentamicin, furagin and nevigramone, the MIC of which for most of the strains was 3.12, 1.6-3.12 and 6.25-12.5 gamma/ml, respectively. The effect of 14 combinations of chemotherapeutics was also studied. The combinations of gentamicin with carbenicillin, gentamicin with ampicillin and monomycin with ampicillin proved to be most effective against the Proteus strains tested. The following combinations may be of practical value: monomycin + carbenicillin, kanamycin + ampicillin, kanamycin + carbenicillin, ampicillin + furagin, gentamicin + nevigramone. The combinations of carbenicillin with furagin and gentamicin with furagin were also rational.

Antibiotics prescription in Nigerian dental healthcare services.

PubMed

Azodo, C C; Ojehanon, P I

2014-09-01

Inappropriate antibiotics prescription in dental healthcare delivery that may result in the emergence of antibiotic-resistant bacteria, is a worldwide concern. The objective of the study was to determine the antibiotics knowledge and prescription patterns among dentists in Nigeria. A total of 160 questionnaires were distributed to dentists attending continuing education courses organized by two organizations in Southern and Northern parts of Nigeria. Data analysis was done using SPSS version 17.0. A total of 146 questionnaires were returned, properly filled, out of 160 questionnaires, giving an overall response rate 91.3%. The clinical factors predominantly influenced the choice of therapeutic antibiotics among the respondents. In this study, the most commonly prescribed antibiotics among the respondents was a combination of amoxicillin and metronidazole. Of the respondents, 136 (93.2%) of them considered antibiotic resistance as a major problem in Nigeria and 102 (69.9%) have experienced antibiotics resistance in dental practice. The major reported conditions for prophylactic antibiotics among the respondents were diabetic mellitus, HIV/AIDS, history of rheumatic fever, other heart anomalies presenting with heart murmur and presence of prosthetic hip. The knowledge of adverse effects of antibiotics was greatest for tooth discoloration which is related to tetracycline. Data from this study revealed the most commonly prescribed antibiotics as a combination of amoxicillin and metronidazole. There existed gaps in prophylactic antibiotic prescription, consideration in the choice of therapeutic antibiotics and knowledge of adverse effects of antibiotics among the studied dentists.

Multiple challenges of antibiotic use in a large hospital in Ethiopia - a ward-specific study showing high rates of hospital-acquired infections and ineffective prophylaxis.

PubMed

Gutema, Girma; Håkonsen, Helle; Engidawork, Ephrem; Toverud, Else-Lydia

2018-05-03

This project aims to study the use of antibiotics in three clinical wards in the largest tertiary teaching hospital in Ethiopia for a period of 1 year. The specific aims were to assess the prevalence of patients on antibiotics, quantify the antibiotic consumption and identify the main indications of use. The material was all the medical charts (n = 2231) retrieved from three clinical wards (internal medicine, gynecology/obstetrics and surgery) in Tikur Anbessa Specialized Hospital (TASH) in Addis Ababa between September 2013 and September 2014. Data collection was performed manually by four pharmacists. Each medical chart represented one patient. About 60% of the patients were admitted to internal medicine, 20% to each of the other two wards. The number of bed days (BD) was on average 16.5. Antibiotics for systemic use were prescribed to 73.7% of the patients (on average: 2.1 antibiotics/patient) of whom 86.6% got a third or fourth generation cephalosporin (mainly ceftriaxone). The average consumption of antibiotics was 81.6 DDD/100BD, varying from 91.8 in internal medicine and 71.6 in surgery to 47.6 in gynecology/obstetrics. The five most frequently occurring infections were pneumonia (26.6%), surgical site infections (21.5%), neutropenic fever (6.9%), sepsis (6.4%) and urinary tract infections (4.7%). About one fourth of the prescriptions were for prophylactic purposes. Hospital acquired infections occurred in 23.5% of the patients (353 cases of surgical site infection). The prescribing was based on empirical treatment and sensitivity testing was reported in only 3.8% of the cases. In the present study from three wards in the largest tertiary teaching hospital in Ethiopia, three out of four patients were prescribed antibiotics, primarily empirically. The mean antibiotic consumption was 81.6 DDD/100BD. Surgical site infections constituted a large burden of the infections treated in the hospital, despite extensive prescribing of prophylaxis. The findings show the need to implement antibiotic stewardship programs in Ethiopian hospitals with focus on rational prescribing, increased sensitivity testing and better procedures to prevent hospital acquired infections.

Endophthalmitis Prophylaxis in Cataract Surgery: Overview of Current Practice Patterns Around the World.

PubMed

Grzybowski, Andrzej; Schwartz, Stephen G; Matsuura, Kazuki; Ong Tone, Stephan; Arshinoff, Steve; Ng, Jonathon Q; Meyer, Jay J; Liu, Wu; Jacob, Soosan; Packer, Mark; Lutfiamida, Rifna; Tahija, Sjakon; Roux, Paul; Malyugin, Boris; Urrets-Zavalia, Julio A; Crim, Nicolas; Esposito, Evangelina; Daponte, Pablo; Pellegrino, Fernando; Graue-Hernandez, Enrique O; Jimenez-Corona, Aida; Valdez-Garcia, Jorge E; Hernandez-Camarena, Julio C; Relhan, Nidhi; Flynn, Harry W; Ravindran, Ravilla D; Behnding, Anders

2017-01-01

Acute-onset postoperative endophthalmitis after cataract surgery remains a rare but important cause of visual loss. There is no global consensus regarding the optimal strategies for prophylaxis of endophthalmitis and practices vary substantially around the world, especially with respect to the use of intracameral antibiotics. The European Society of Cataract & Refractive Surgeons in a randomized clinical trial (2007) reported an approximately 5-fold reduction in endophthalmitis rates associated with the use of intracameral cefuroxime. Despite this report, the use of intracameral antibiotics has not been universally adopted. Various endophthalmitis prophylaxis patterns around the world (including the United States, Canada, Australia/New Zealand, Japan, China, India, Indonesia, South Africa, Argentina, Russia, Sweden and Mexico) are compared. Each contributing author was asked to provide similar information, including endophthalmitis rates based on published studies, current practice patterns, and in some cases original survey data. Various methods were used to obtain this information, including literature reviews, expert commentary, and some new survey data not previously published. Many different practice patterns were reported from around the world, specifically with respect to the use of intracameral antibiotics. There is no worldwide consensus regarding endophthalmitis prophylaxis with cataract surgery. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

[Antibacterial therapy of cholecystocholangitis in viral hepatitis].

PubMed

Andreĭchin, M A; Kiĭko, L G; Il'ina, N I

1984-04-01

The chemotherapy of cholecystocholangitis in patients with virus hepatitis was estimated. Antibiotics, furagin and pathogenetic drugs were used for the treatment. The antibiotics were chosen with regard to their sensitivity to the bile microflora. This resulted in sanation of the bile ducts. Furagin was less effective. The use of the pathogenetic drugs alone was ineffective in the majority of patients.

H2S: a universal defense against antibiotics in bacteria.

PubMed

Shatalin, Konstantin; Shatalina, Elena; Mironov, Alexander; Nudler, Evgeny

2011-11-18

Many prokaryotic species generate hydrogen sulfide (H(2)S) in their natural environments. However, the biochemistry and physiological role of this gas in nonsulfur bacteria remain largely unknown. Here we demonstrate that inactivation of putative cystathionine β-synthase, cystathionine γ-lyase, or 3-mercaptopyruvate sulfurtransferase in Bacillus anthracis, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli suppresses H(2)S production, rendering these pathogens highly sensitive to a multitude of antibiotics. Exogenous H(2)S suppresses this effect. Moreover, in bacteria that normally produce H(2)S and nitric oxide, these two gases act synergistically to sustain growth. The mechanism of gas-mediated antibiotic resistance relies on mitigation of oxidative stress imposed by antibiotics.

MICROBIAL PROFILE AND ANTIBIOTIC SUSCEPTIBILITY PATTERNS OF PATHOGENS CAUSING VENTILATOR- ASSOCIATED PNEUMONIA AT INTENSIVE CARE UNIT, SESTRE MILOSRDNICE UNIVERSITY HOSPITAL CENTER, ZAGREB, CROATIA.

PubMed

Turković, Tihana Magdić; Grginić, Ana Gverić; Cucujić, Branka Đuras; Gašpar, Božena; Širanović, Mladen; Perić, Mladen

2015-06-01

Ventilator-associated pneumonia (VAP) is very common in many intensive care Units, but there are still many uncertainties about VAP, especially about the choice of initial empiric antibiotics. The incidence of specific pathogens with different susceptibility patterns causing VAP varies from hospital to hospital. This is the reason why empiric initial antibiotic treatment for VAP should be based not only on general guidelines (that recommend therapy according to the presence of risk factors for multidrug-resistant bacteria), but also on up-to-date information on local epidemiology. The aim of this study was to determine the microbial profile of pathogens causing VAP and their antibiotic susceptibility patterns. The study was conducted in the 15-bed surgical and neurosurgical Intensive Care Unit, Department of Anesthesiology and Intensive Care, Sestre milosrdnice University Hospital Center, Zagreb, Croatia. Retrospective data were collected from September 2009 to March 2013. All patients that developed VAP during the study period were eligible for the study. According to study results, the incidence of VAP was 29.4%. The most commonly isolated bacterium was Staphylococcus aureus (21.1%), followed by Pseudomonas aeruginosa (19.0%) and Acinetobacter species (13.6%). All Staphylococcus aureus isolates were susceptible to vancomycin and linezolid. Pseudomonas aeruginosa showed 100% susceptibility to cefepime and very high susceptibility to pip'eracillin-tazobactam (96%), ceftazidime (93%) and ciprofloxacin (89%). Ampicillin-sulbactam was highly effective for Acinetobacter species, showing resistance in only 8% of isolates. In conclusion, according to study data, appropriate empiric antibiotic therapy for patients with VAP without risk factors for multidrug-resistant bacteria is ceftriaxone and for patients with risk factors for multidrug-resistant bacteria ampicillin-sulbactam plus cefepime plus vancomycin or linezolid.

Antimicrobial Prescribing Practices Following Publication of Guidelines for the Prevention of Infections Associated With Combat-Related Injuries

PubMed Central

Tribble, David R.; Lloyd, Bradley; Weintrob, Amy; Ganesan, Anuradha; Murray, Clinton K.; Li, Ping; Bradley, William; Fraser, Susan; Warkentien, Tyler; Gaskins, Lakisha J.; Seillier-Moiseiwitsch, Françoise; Millar, Eugene V.; Hospenthal, Duane R.

2018-01-01

Background Timely and limited antibiotic prophylaxis (postinjury antimicrobial therapy) targeting specific traumatic injuries is a well-recognized measure to lessen posttraumatic infection. Modern military combat injuries raise significant challenges because of complex multiple injuries and limited data derived directly from well-controlled trials to base recommendations. Expert consensus review of available evidence led to published guidance for selection and duration of antimicrobial therapy for combat-related trauma infection prevention. This analysis evaluates antibiotic-prescribing practices by military physicians in the operational theater relative to the published guidance. Methods Trauma history and infectious disease-specific inpatient care information is captured through the Joint Theater Trauma Registry along with a supplemental infectious disease module. Injury patterns are classified based on documented International Classification of Diseases-9th Revision codes with a composite assessment of each patient’s injury pattern. Antimicrobial use categorized as prophylaxis is prescribed within the first 48 hours postinjury. Adherence to published guidance is reported along with patient characteristics and injury severity to assess for potential explanations of nonadherence. Results During June to November 2009, 75% of the 610 eligible trauma patients received antimicrobial prophylaxis. Adherence to the recommended antibiotic agent on the day of injury was in the range of 46% to 50% for the most common extremity injury patterns and 10% in penetrating abdominal injuries. Antibiotics were given in 39% of patients sustaining injuries that are recommendations to not receive antimicrobial prophylaxis. Conclusions This first evaluation of combat trauma-related antibiotic prophylaxis shows adherence levels comparable or superior to reported rates in civilian settings despite the austere, frequently mass casualty environment. Areas for interval surveillance and education-based strategies for improved adherence to practice guidance are identified. PMID:21814096

Comparative analysis of antibiotic resistance and phylogenetic group patterns in human and porcine urinary tract infectious Escherichia coli.

PubMed

Hancock, Viktoria; Nielsen, Eva Møller; Krag, Louise; Engberg, Jørgen; Klemm, Per

2009-11-01

Urinary tract infections (UTIs) are one of the most common infectious diseases in humans and domestic animals such as pigs. The most frequent infectious agent in such infections is Escherichia coli. Virulence characteristics of E. coli UTI strains range from highly virulent pyelonephritis strains to relatively benign asymptomatic bacteriuria strains. Here we analyse a spectrum of porcine and human UTI E. coli strains with respect to their antibiotic resistance patterns and their phylogenetic groups, determined by multiplex PCR. The clonal profiles of the strains differed profoundly; whereas human strains predominantly belonged to clonal types B2 and D, these were not seen among the porcine strains, which all belonged to the E. coli clonal groups A and B1. Contrary to the human strains, the majority of the porcine strains were multidrug resistant. The distinct profiles of the porcine strains suggest selective pressure due to extensive antibiotic use.

Mature biofilms of Enterococcus faecalis and Enterococcus faecium are highly resistant to antibiotics.

PubMed

Holmberg, Anna; Rasmussen, Magnus

2016-01-01

Enterococcus faecalis and Enterococcus faecium are important nosocomial pathogens that form biofilms on implanted materials. We compare the antibiotic sensitivity of bacteria in new (established during 24 hours) and mature (established during 120 hours) enterococcal biofilms. Mature biofilms contained more bacteria and were much more tolerant to antibiotics, including rifampicin-containing combinations, as judged by determination of minimal biofilm eradication concentrations and by time-kill experiments of bacteria in biofilms formed on beads of bone cement. Copyright © 2016 Elsevier Inc. All rights reserved.

Metabolomic approach to optimizing and evaluating antibiotic treatment in the axenic culture of cyanobacterium Nostoc flagelliforme.

PubMed

Han, Pei-pei; Jia, Shi-ru; Sun, Ying; Tan, Zhi-lei; Zhong, Cheng; Dai, Yu-jie; Tan, Ning; Shen, Shi-gang

2014-09-01

The application of antibiotic treatment with assistance of metabolomic approach in axenic isolation of cyanobacterium Nostoc flagelliforme was investigated. Seven antibiotics were tested at 1-100 mg L(-1), and order of tolerance of N. flagelliforme cells was obtained as kanamycin > ampicillin, tetracycline > chloromycetin, gentamicin > spectinomycin > streptomycin. Four antibiotics were selected based on differences in antibiotic sensitivity of N. flagelliforme and associated bacteria, and their effects on N. flagelliforme cells including the changes of metabolic activity with antibiotics and the metabolic recovery after removal were assessed by a metabolomic approach based on gas chromatography-mass spectrometry combined with multivariate analysis. The results showed that antibiotic treatment had affected cell metabolism as antibiotics treated cells were metabolically distinct from control cells, but the metabolic activity would be recovered via eliminating antibiotics and the sequence of metabolic recovery time needed was spectinomycin, gentamicin > ampicillin > kanamycin. The procedures of antibiotic treatment have been accordingly optimized as a consecutive treatment starting with spectinomycin, then gentamicin, ampicillin and lastly kanamycin, and proved to be highly effective in eliminating the bacteria as examined by agar plating method and light microscope examination. Our work presented a strategy to obtain axenic culture of N. flagelliforme and provided a method for evaluating and optimizing cyanobacteria purification process through diagnosing target species cellular state.

Relationship between antibiotic- and disinfectant-resistance profiles in bacteria harvested from tap water.

PubMed

Khan, Sadia; Beattie, Tara K; Knapp, Charles W

2016-06-01

Chlorination is commonly used to control levels of bacteria in drinking water; however, viable bacteria may remain due to chlorine resistance. What is concerning is that surviving bacteria, due to co-selection factors, may also have increased resistance to common antibiotics. This would pose a public health risk as it could link resistant bacteria in the natural environment to human population. Here, we investigated the relationship between chlorine- and antibiotic-resistances by harvesting 148 surviving bacteria from chlorinated drinking-water systems and compared their susceptibilities against chlorine disinfectants and antibiotics. Twenty-two genera were isolated, including members of Paenibacillus, Burkholderia, Escherichia, Sphingomonas and Dermacoccus species. Weak (but significant) correlations were found between chlorine-tolerance and minimum inhibitory concentrations against the antibiotics tetracycline, sulfamethoxazole and amoxicillin, but not against ciprofloxacin; this suggest that chlorine-tolerant bacteria are more likely to also be antibiotic resistant. Further, antibiotic-resistant bacteria survived longer than antibiotic-sensitive organisms when exposed to free chlorine in a contact-time assay; however, there were little differences in susceptibility when exposed to monochloramine. Irrespective of antibiotic-resistance, spore-forming bacteria had higher tolerance against disinfection compounds. The presence of chlorine-resistant bacteria surviving in drinking-water systems may carry additional risk of antibiotic resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Changing the Antibiotic Prescribing of general practice registrars: the ChAP study protocol for a prospective controlled study of a multimodal educational intervention.

PubMed

van Driel, Mieke L; Morgan, Simon; Tapley, Amanda; McArthur, Lawrie; McElduff, Patrick; Yardley, Lucy; Dallas, Anthea; Deckx, Laura; Mulquiney, Katie; Davis, Joshua S; Davey, Andrew; Henderson, Kim; Little, Paul; Magin, Parker J

2016-06-06

Australian General Practitioners (GPs) are generous prescribers of antibiotics, prompting concerns including increasing antimicrobial resistance in the community. Recent data show that GPs in vocational training have prescribing patterns comparable with the high prescribing rate of their established GP supervisors. Evidence-based guidelines consistently advise that antibiotics are not indicated for uncomplicated upper respiratory tract infections (URTI) and are rarely indicated for acute bronchitis. A number of interventions have been trialled to promote rational antibiotic prescribing by established GPs (with variable effectiveness), but the impact of such interventions in a training setting is unclear. We hypothesise that intervening while early-career GPs are still developing their practice patterns and prescribing habits will result in better adherence to evidence-based guidelines as manifested by lower antibiotic prescribing rates for URTIs and acute bronchitis. The intervention consists of two online modules, a face-to-face workshop for GP trainees, a face-to-face workshop for their supervisors and encouragement for the trainee-supervisor dyad to include a case-based discussion of evidence-based antibiotic prescribing in their weekly one-on-one teaching meetings. We will use a non-randomised, non-equivalent control group design to assess the impact on antibiotic prescribing for acute upper respiratory infections and acute bronchitis by GP trainees in vocational training. Early-career GPs who are still developing their clinical practice and prescribing habits are an underutilized target-group for interventions to curb the growth of antimicrobial resistance in the community. Interventions that are embedded into existing training programs or are linked to continuing professional development have potential to increase the impact of existing interventions at limited additional cost. Australian New Zealand Clinical Trials Registry, ACTRN12614001209684 (registered 17/11/2014).

A Mixed-Methods Pilot Study to Assess Perceptions of Antimicrobial Stewardship in Nursing Homes

PubMed Central

Carter, Rebecca R.; Montpetite, Michelle M.; Jump, Robin L. P.

2016-01-01

Objectives Practicing antimicrobial stewardship in nursing homes faces many challenges, particularly in non-academic settings. We sought to identify features of community nursing home environments that are associated with lower rates of overall antibiotic use. Design In this pilot study, we used an explanatory sequential design that incorporated comparative feedback about antibiotic use to inform a discussion about antimicrobial stewardship practices among community nursing homes. Measurements For the quantitative phase, we measured the number of antibiotic prescriptions, length of therapy and days of therapy/1000 days of care at 6 nursing homes. For the qualitative phase, we conducted semi-structured interviews with healthcare workers in leadership positions at 5 community nursing homes. Transcripts from the recorded interviews were assessed using emergent thematic analysis. For the triangulation phase, we evaluated themes from the semi-structured interviews in the context of each NHs antibiotic use. Results The number of antibiotic prescriptions ranged from 172 to 1244, with 50% to 83% written for ≤ 7 days. All nursing homes reported a similar proportion of fluoroquinolone use (27–32% days of therapy). Triangulation yielded 6 themes for which the environment at each facility ranged from less to more supportive antimicrobial stewardship: practice patterns, external influences, infection control, leadership, communication and facility culture. All nursing homes reported pressure from well-intentioned family members to prescribe antibiotics. Nursing homes with shorter lengths of therapy and lower overall antibiotic use were consonant with an environment more supportive of antimicrobial stewardship. Conclusion Our findings suggest several features of nursing homes that are supportive of antimicrobial stewardship: practice patterns grounded in established diagnostic criteria, proactive infection control and prevention, open communication and interconnectedness among staff. PMID:28152171

Variability in Pediatric Infectious Disease Consultants' Recommendations for Management of Community-Acquired Pneumonia

PubMed Central

Hersh, Adam L.; Shapiro, Daniel J.; Newland, Jason G.; Polgreen, Philip M.; Beekmann, Susan E.; Shah, Samir S.

2011-01-01

Background Community-acquired pneumonia (CAP) is a common childhood infection. CAP complications, such as parapneumonic empyema (PPE), are increasing and are frequently caused by antibiotic-resistant organisms. No clinical guidelines currently exist for management of pediatric CAP and no published data exist about variations in antibiotic prescribing patterns. Our objectives were to describe variation in CAP clinical management for hospitalized children by pediatric infectious disease consultants and to examine associations between recommended antibiotic regimens and local antibiotic resistance levels. Methods We surveyed pediatric members of the Emerging Infections Network, which consists of 259 pediatric infectious disease physicians. Participants responded regarding their recommended empiric antibiotic regimens for hospitalized children with CAP with and without PPE and their recommendations for duration of therapy. Participants also provided information about the prevalence of penicillin non-susceptible S. pneumoniae and methicillin-resistant S. aureus (MRSA) in their community. Results We received 148 responses (57%). For uncomplicated CAP, respondents were divided between recommending beta-lactams alone (55%) versus beta-lactams in combination with another class (40%). For PPE, most recommended a combination of a beta-lactam plus an anti-MRSA agent, however, they were divided between clindamycin (44%) and vancomycin (57%). The relationship between reported antibiotic resistance and empiric regimen was mixed. We found no relationship between aminopenicillin use and prevalence of penicillin non-suscepetible S. pneumoniae or clindamycin use and clindamycin resistance, however, respondents were more likely to recommend an anti-MRSA agent when MRSA prevalence increased. Conclusions Substantial variability exists in recommendations for CAP management. Development of clinical guidelines via antimicrobial stewardship programs and dissemination of data about local antibiotic resistance patterns represent opportunities to improve care. PMID:21655259

Urinary tract infections in the infant.

PubMed

Arshad, Mehreen; Seed, Patrick C

2015-03-01

Urinary tract infection (UTI) in an infant may be the first indication of an underlying renal disorder. Early recognition and initiation of adequate therapy for UTI is important to reduce the risk of long-term renal scarring. Ampicillin and gentamicin are traditionally the empiric treatment of choice; however, local antibiotic resistance patterns should be considered. Maternal antibiotics during pregnancy also increase the risk of resistant pathogens during neonatal UTI. Long-term management after the first UTI in infants remains controversial because of lack of specific studies in this age group and the risk-benefit issues for antibiotic prophylaxis between reduced recurrent disease and emergent antibiotic resistance. Copyright © 2015 Elsevier Inc. All rights reserved.

Assessment of antibiotic use in farm animals in Rwanda.

PubMed

Manishimwe, Rosine; Nishimwe, Kizito; Ojok, Lonzy

2017-08-01

The irrational use of antibiotics in humans and animals is highly related to the emergence and increase of antibiotic-resistant bacteria worldwide. A cross-sectional survey aimed at evaluating the current level of practices regarding antibiotic use in farm animals in Rwanda was carried out countrywide. Interviews were conducted on 229 farmers rearing different types of animals. The study has revealed that almost all respondent farmers could name at least one antibiotic used in farm animals and peni-streptomycin was named by most of them (95.6%). The use of antibiotics in farm animals was observed in the majority of respondents (97.4%). It was found that 44.4 and 26.5% of respondents reported that they used antibiotics for disease prevention and growth promotion, respectively. The use of non-prescribed antibiotics in animals was also reported by more than the half of respondent farmers (55.6%). The majority of farmers had a moderate level of practices regarding antibiotic use in farm animals (73.5%), very few had a high level (26%) and only one respondent had a low level. The high level of practices in regard to antibiotic use in animals was associated with the location of the farm, the type of reared animals, and the rearing system. The results of this study give an insight into antibiotics usage practices in farm animals in Rwanda. The generated information can guide sensitizations and promotions of the prudent use of antibiotics among farmers in order to limit the increase of antibiotic resistance in the country.

Why sensitive bacteria are resistant to hospital infection control

PubMed Central

van Kleef, Esther; Luangasanatip, Nantasit; Bonten, Marc J; Cooper, Ben S

2017-01-01

Background: Large reductions in the incidence of antibiotic-resistant strains of Staphylococcus aureus and Clostridium difficile have been observed in response to multifaceted hospital-based interventions. Reductions in antibiotic-sensitive strains have been smaller or non-existent. It has been argued that since infection control measures, such as hand hygiene, should affect resistant and sensitive strains equally, observed changes must have largely resulted from other factors, including changes in antibiotic use. We used a mathematical model to test the validity of this reasoning. Methods: We developed a mechanistic model of resistant and sensitive strains in a hospital and its catchment area. We assumed the resistant strain had a competitive advantage in the hospital and the sensitive strain an advantage in the community. We simulated a hospital hand hygiene intervention that directly affected resistant and sensitive strains equally. The annual incidence rate ratio ( IRR) associated with the intervention was calculated for hospital- and community-acquired infections of both strains. Results: For the resistant strain, there were large reductions in hospital-acquired infections (0.1 ≤ IRR ≤ 0.6) and smaller reductions in community-acquired infections (0.2 ≤ IRR ≤  0.9). These reductions increased in line with increasing importance of nosocomial transmission of the strain. For the sensitive strain, reductions in hospital acquisitions were much smaller (0.6 ≤ IRR ≤ 0.9), while communityacquisitions could increase or decrease (0.9 ≤ IRR ≤ 1.2). The greater the importance of the community environment for the transmission of the sensitive strain, the smaller the reductions. Conclusions: Counter-intuitively, infection control interventions, including hand hygiene, can have strikingly discordant effects on resistant and sensitive strains even though they target them equally, following differences in their adaptation to hospital and community-based transmission. Observed lack of effectiveness of control measures for sensitive strains does not provide evidence that infection control interventions have been ineffective in reducing resistant strains. PMID:29260003

Why sensitive bacteria are resistant to hospital infection control.

PubMed

van Kleef, Esther; Luangasanatip, Nantasit; Bonten, Marc J; Cooper, Ben S

2017-01-01

Large reductions in the incidence of antibiotic-resistant strains of Staphylococcus aureus and Clostridium difficile have been observed in response to multifaceted hospital-based interventions. Reductions in antibiotic-sensitive strains have been smaller or non-existent. It has been argued that since infection control measures, such as hand hygiene, should affect resistant and sensitive strains equally, observed changes must have largely resulted from other factors, including changes in antibiotic use. We used a mathematical model to test the validity of this reasoning. We developed a mechanistic model of resistant and sensitive strains in a hospital and its catchment area. We assumed the resistant strain had a competitive advantage in the hospital and the sensitive strain an advantage in the community. We simulated a hospital hand hygiene intervention that directly affected resistant and sensitive strains equally. The annual incidence rate ratio (IRR) associated with the intervention was calculated for hospital- and community-acquired infections of both strains. For the resistant strain, there were large reductions in hospital-acquired infections (0.1 ≤ IRR ≤ 0.6) and smaller reductions in community-acquired infections (0.2 ≤ IRR ≤ 0.9). These reductions increased in line with increasing importance of nosocomial transmission of the strain. For the sensitive strain, reductions in hospital acquisitions were much smaller (0.6 ≤ IRR ≤ 0.9), while community acquisitions could increase or decrease (0.9 ≤ IRR ≤ 1.2). The greater the importance of the community environment for the transmission of the sensitive strain, the smaller the reductions. Counter-intuitively, infection control interventions, including hand hygiene, can have strikingly discordant effects on resistant and sensitive strains even though they target them equally. This follows from differences in their adaptation to hospital- and community-based transmission. Observed lack of effectiveness of control measures for sensitive strains does not provide evidence that infection control interventions have been ineffective in reducing resistant strains.

Failure of Syndrome-Based Diarrhea Management Guidelines to Detect Shigella Infections in Kenyan Children

PubMed Central

Pavlinac, P. B.; Denno, D. M.; John-Stewart, G. C.; Onchiri, F. M.; Naulikha, J. M.; Odundo, E. A.; Hulseberg, C. E.; Singa, B. O.; Manhart, L. E.; Walson, J. L.

2016-01-01

Background Shigella is a leading cause of childhood diarrhea mortality in sub-Saharan Africa. Current World Health Organization guidelines recommend antibiotics for children in non cholera-endemic areas only in the presence of dysentery, a proxy for suspected Shigella infection. Methods To assess the sensitivity and specificity of the syndromic diagnosis of Shigella-associated diarrhea, we enrolled children aged 6 months to 5 years presenting to 1 of 3 Western Kenya hospitals between November 2011 and July 2014 with acute diarrhea. Stool samples were tested using standard methods for bacterial culture and multiplex polymerase chain reaction for pathogenic Escherichia coli. Stepwise multivariable logit models identified factors to increase the sensitivity of syndromic diagnosis. Results Among 1360 enrolled children, median age was 21 months (interquartile range, 11–37), 3.4% were infected with human immunodeficiency virus, and 16.5% were stunted (height-for-age z-score less than −2). Shigella was identified in 63 children (4.6%), with the most common species being Shigella sonnei (53.8%) and Shigella flexneri (40.4%). Dysentery correctly classified 7 of 63 Shigella cases (sensitivity, 11.1%). Seventy-eight of 1297 children without Shigella had dysentery (specificity, 94.0%). The combination of fecal mucous, age over 23 months, and absence of excessive vomiting identified more children with Shigella-infection (sensitivity, 39.7%) but also indicated antibiotics in more children without microbiologically confirmed Shigella (specificity, 82.7%). Conclusions Reliance on dysentery as a proxy for Shigella results in the majority of Shigella-infected children not being identified for antibiotics. Field-ready rapid diagnostics or updated evidence-based algorithms are urgently needed to identify children with diarrhea most likely to benefit from antibiotic therapy. PMID:26407270

An eight-year review of blood culture and susceptibility among sepsis cases in an emergency department in Northeastern Malaysia.

PubMed

Hashairi, F; Hasan, H; Azlan, K; Deris, Z Z

2011-12-01

An understanding of common pathogens and their antibiotic sensitivity patterns is critical for proper management of sepsis in Emergency Department (ED). The goal of the study was to identify common organisms isolated from blood cultures of patients attended to ED and their antimicrobial susceptibility. Beginning from 2002, all cases of positive blood culture collected by the ED, Hospital Universiti Sains Malaysia (HUSM) were recorded and analysed. Over the period of eight years, we documented 995 cases of positive blood cultures. Of these samples, 549 (55.2%) were Gram-negative bacteria; 419 (42.1%) were Gram-positive bacteria; 10 (1.0%) were anaerobic organisms; 10 (1.0%) were fungus; and 7 (0.7%) cases were mixed organisms. Gram-negative bacteria were observed to develop more resistance to antimicrobial agents, especially those commonly used in an outpatient setting with less than 80% sensitivity to ampicillin, cotrimoxazole and ciprofloxacin. By contrast, there has been no marked change in the sensitivity trends of Gram-positive bacteria over the same period. In conclusion, ED physicians are more equipped to initiate empirical antimicrobial therapy especially when dealing with possibility of Gram-negative sepsis.

Bacterial adaptation to sublethal antibiotic gradients can change the ecological properties of multitrophic microbial communities

PubMed Central

Friman, Ville-Petri; Guzman, Laura Melissa; Reuman, Daniel C.; Bell, Thomas

2015-01-01

Antibiotics leak constantly into environments due to widespread use in agriculture and human therapy. Although sublethal concentrations are well known to select for antibiotic-resistant bacteria, little is known about how bacterial evolution cascades through food webs, having indirect effect on species not directly affected by antibiotics (e.g. via population dynamics or pleiotropic effects). Here, we used an experimental evolution approach to test how temporal patterns of antibiotic stress, as well as migration within metapopulations, affect the evolution and ecology of microcosms containing one prey bacterium, one phage and two protist predators. We found that environmental variability, autocorrelation and migration had only subtle effects for population and evolutionary dynamics. However, unexpectedly, bacteria evolved greatest fitness increases to both antibiotics and enemies when the sublethal levels of antibiotics were highest, indicating positive pleiotropy. Crucially, bacterial adaptation cascaded through the food web leading to reduced predator-to-prey abundance ratio, lowered predator community diversity and increased instability of populations. Our results show that the presence of natural enemies can modify and even reverse the effects of antibiotics on bacteria, and that antibiotic selection can change the ecological properties of multitrophic microbial communities by having indirect effects on species not directly affected by antibiotics. PMID:25833854

Bacterial adaptation to sublethal antibiotic gradients can change the ecological properties of multitrophic microbial communities.

PubMed

Friman, Ville-Petri; Guzman, Laura Melissa; Reuman, Daniel C; Bell, Thomas

2015-05-07

Antibiotics leak constantly into environments due to widespread use in agriculture and human therapy. Although sublethal concentrations are well known to select for antibiotic-resistant bacteria, little is known about how bacterial evolution cascades through food webs, having indirect effect on species not directly affected by antibiotics (e.g. via population dynamics or pleiotropic effects). Here, we used an experimental evolution approach to test how temporal patterns of antibiotic stress, as well as migration within metapopulations, affect the evolution and ecology of microcosms containing one prey bacterium, one phage and two protist predators. We found that environmental variability, autocorrelation and migration had only subtle effects for population and evolutionary dynamics. However, unexpectedly, bacteria evolved greatest fitness increases to both antibiotics and enemies when the sublethal levels of antibiotics were highest, indicating positive pleiotropy. Crucially, bacterial adaptation cascaded through the food web leading to reduced predator-to-prey abundance ratio, lowered predator community diversity and increased instability of populations. Our results show that the presence of natural enemies can modify and even reverse the effects of antibiotics on bacteria, and that antibiotic selection can change the ecological properties of multitrophic microbial communities by having indirect effects on species not directly affected by antibiotics. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Effect of Tetracycline Antibiotics on Performance and Microbial Community of Algal Photo-Bioreactor.

PubMed

Taşkan, Ergin

2016-07-01

Tetracycline antibiotics have been increasingly used in medical applications and have been found in wastewater treatment plants as a result of human and industrial activities. This study investigates the combined effects of tetracycline antibiotics on the performance of an algal photo-bioreactor operated under different antibiotic concentrations in the ranges of 0.25 to 30 mg/L and considers the inhibition of algal growth, carbon and nutrient removal rates, and eukaryotic and cyanobacterial algal community changes. The results indicated that increases in the concentration of tetracycline mixtures have adverse effects on the algal community and the performance of a photo-bioreactor, and the eukaryotic algae species were more sensitive to tetracycline antibiotics than were the cyanobacterial species. Cultivation tests showed that approximately 94 % growth inhibition of mixed algae occurred at 30 mg/L.

Pharmacological Targeting of the Host-Pathogen Interaction: Alternatives to Classical Antibiotics to Combat Drug-Resistant Superbugs

PubMed Central

Munguia, Jason; Nizet, Victor

2017-01-01

The rise of multidrug-resistant pathogens and the dearth of new antibiotic development place an existential strain on successful infectious disease therapy. Breakthrough strategies that go beyond classical antibiotic mechanisms are needed to combat this looming public health catastrophe. Reconceptualizing antibiotic therapy in the richer context of the host-pathogen interaction is required for innovative solutions. By defining specific virulence factors, the essence of a pathogen, and pharmacologically neutralizing their activities, one can block disease progression and sensitize microbes to immune clearance. Likewise, host-directed strategies to boost phagocyte bactericidal activity, enhance leukocyte recruitment, or reverse pathogen-induced immunosuppression seek to replicate the success of cancer immunotherapy in the field of infectious diseases. The answer to the threat of multidrug-resistant pathogens lies “outside-the-box” of current antibiotic paradigms. PMID:28283200

Staphylococcus aureus carriage rates and antibiotic resistance patterns in patients with acne vulgaris.

PubMed

Delost, Gregory R; Delost, Maria E; Armile, James; Lloyd, Jenifer

2016-04-01

Overuse of antibiotics has led to the development of antibiotic-resistant strains of Staphylococcus aureus, which are occurring more frequently within the community. We sought to determine whether long-term antibiotic therapy for acne alter the carriage rate and antibiotic resistance profiles of S aureus. This was a prospective, cross-sectional, quasiexperimental study. Samples of anterior nares were obtained from dermatology patients given a diagnosis of acne vulgaris (n = 263) who were treated with antibiotics (n = 142) or who were not treated with antibiotics (n = 121). Specimens were tested for the presence of S aureus by growth on mannitol salt agar and then isolated on 5% sheep blood agar. Identification was confirmed based on colonial morphology, Gram stain, catalase, and coagulase testing. Antibiotic susceptibility testing was performed using the VITEK 2 system (bioMerieux, Marcy-l'Étoile, France). The S aureus carriage rate was significantly lower in patients with acne treated with antibiotics (6.3%) compared with those not treated with antibiotics (15.7%; P = .016). The percentage of S aureus isolates resistant to 1 or more antibiotics did not significantly differ between the 2 groups (P = .434). Cross-sectional study, patient compliance, and effects of prior acne treatments are limitations. Treatment of patients with acne using antibiotics decreases the S aureus carriage rate but does not significantly alter the antibiotic resistance rates. Copyright © 2015 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Antibiotic treatment of acute respiratory infections in acute care settings.

PubMed

Gonzales, Ralph; Camargo, Carlos A; MacKenzie, Thomas; Kersey, Ayanna S; Maselli, Judith; Levin, Sara K; McCulloch, Charles E; Metlay, Joshua P

2006-03-01

To examine the patterns of antibiotic use for acute respiratory tract infections (ARIs) in acute care settings. Chart reviews were performed retrospectively on a random sample of adult ARI visits to seven Veterans Affairs (VA) and seven non-VA emergency departments (EDs) for the period of November 2003 to February 2004. Visits were limited to those discharged to home and those with primary diagnoses of antibiotic-responsive (pneumonia, acute exacerbation of chronic bronchitis, pharyngitis, sinusitis) and antibiotic-nonresponsive conditions (acute bronchitis, nonspecific upper respiratory tract infection [URI]). Results are expressed as adjusted odds ratios with 95% confidence intervals. Of 2,270 ARI visits, 62% were for antibiotic-nonresponsive diagnoses. Seventy-two percent of acute bronchitis and 38% of URI visits were treated with antibiotics (p < 0.001). Stratified analyses show that antibiotic prescription rates were similar among attending-only and housestaff-associated visits for antibiotic-responsive diagnoses (p = 0.11), and acute bronchitis (76% vs. 59%; p = 0.31). However, the antibiotic prescription rate for URIs was greater for attending-only visits compared with housestaff-associated visits (48% vs. 15%; p = 0.01). Antibiotic prescription rates for total ARIs varied between sites, ranging from 42% to 89%. Patient age, gender, race and ethnicity, smoking status, comorbidities, and clinical setting (VA vs. non-VA) were not independently associated with antibiotic prescribing. Acute care settings are important targets for reducing inappropriate antibiotic prescribing. The mechanisms accounting for lower antibiotic prescription rates observed with housestaff-associated visits merit further study.