Antibiotic sensitivity pattern of causative organisms of neonatal septicemia in an urban hospital of Bangladesh.

PubMed

Monjur, Forhad; Rizwan, Farhana; Asaduzzaman, Muhammad; Nasrin, Nishat; Ghosh, Nobo Krishna; Apu, Apurba Sarker; Haque, Fazlul

2010-06-01

The information of the sensitivity pattern of the causative organisms is very important for effective control of septicemia in neonates. To determine the proportion and profile of pathogenic bacteria in the blood cultures of the neonates with clinically suspected septicemia and their susceptibility pattern to antimicrobial agents for developing a unified antibiotic treatment protocol. A cross-sectional retrospective study was conducted over a period of 3 year and 4 months (39 months). The study included 1000 patients admitted in the selected hospital in Bangladesh. Blood samples for culture were taken aseptically before starting antibiotic therapy. Microorganisms were isolated and identified by standard microbiological processes which include colony morphology, Gram stain, and biochemical profiles. Antimicrobial sensitivity patterns were performed by Kirby-Bauer's disc diffusion method against imipenem, ciprofloxacin, ceftazidime, chloramphenicol, netilmicin, gentamicin, ceftriaxone, aztreonam, cefotaxime, cephalexin, and ampicillin. Among the patients, 633 (63.3%) were males and 367 (36.7%) were females. Blood cultures were found positive in 194 (19.4%) neonates. The organisms isolated were Pseudomonas spp. (31.4%), Klebsiella pneumoniae (23.2%), Staphylococcus aureus (12.4%), Escherichia coli (7.2%), Acinatobactor (5.7%), Gram-negative Bacilli (4.1%), Flavobacterium spp. (3.6%), Serratia spp. (5.7%), Citrobacter fruendi (3.1%), Streptococcus species (2.6%), and Enterobacter spp. (1.0%). A majority of the bacterial isolates in neonatal sepsis were found sensitive to imipenem (91.8%) and ciprofloxacin (57.2%) and resistant to commonly used antibiotics, eg. ampicillin (96.4%) and cephalexin (89.2%). The problem can be mitigated by careful selection and prudent use of available antibiotics.

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.

Antimicrobial susceptibility pattern of Klebsiella species from Ebonyi State University Teaching Hospital Abakaliki, Nigeria.

PubMed

Akujobi, C N

2005-12-01

Klesiella specie isolated from clinical specimens from Ebonyi State University Teaching Hospital (EBSUTH). Abakakliki were studied to determine the antimicrobial susceptibility pattern. Between January, 2003 and September 2004 a total of 3.600 specimens processed in the routine Medical Microbiology laboratory of EBSUTH, of which 245(6.8%) yielded Klebsiella species, with 84 from out - patients and 161 from in - patients. The number of isolates from various samples were: Urine 126, Sputum 37 Endocervical swab 13, Aspirates 8, High Vaginal Swab 7, Blood 3, Eye Swab, Ear Swab and Cerebrospinal fluid were 2 samples each. Organisms were identified by conventional methods. Antimicrobial susceptibility was done by the disk diffusion methods. The antimicrobial disk used include: Ceftazidime, Cefuroxime, Cefotaxine, Augmentin, Pefloxacin (30ug), Doxycyline (25ug) Genticin (10 ug) Ciprofloacin and Ofloxacin (5ug) each and Erythromycin (15ug). All were Oxoid products. Results were interpreted according to NCCLS criteria. Klebsilla species were isolated mostly from urine specimens (51.4%) followed by wound swabs (18.4%). Antimicrobial susceptibility to various groups drugs used was generally poor. The most sensitive antimicrobial was Ciprofloxacin with 121(49.4%) isolates susceptible to it, followed by Gentamicin with 95 (38.8%) and Ceftazidime with 90(36.7%). Seventeen isolates were multiresistant to all the antimicrobial agents used. The result of this study will help in the empiric therapy of infection caused by Klebsiella species in Ebonyi State University Teaching Hospital, Abakaliki, Nigeria but continuous surverillance of antimicrobial resistance of the organnisn is very necessary in the formulation of a sound antibiotic policy in the hospital.

Nosocomial bloodstream infections in a Turkish university hospital: study of Gram-negative bacilli and their sensitivity patterns.

PubMed

Köseoğlu , O; Kocagöz, S; Gür, D; Akova, M

2001-06-01

Treatment of nosocomial bacteraemia is usually governed by the surveillance results of the particular unit. Such results are especially important when antimicrobial resistance rates are high. Multiresistant isolates including Gram-negatives producing extended-spectrum beta-lactamases have been frequently reported in tertiary care units in Turkey. In this study, antimicrobial susceptibilities of Gram-negative blood isolates (n=348) were determined by microbroth dilution tests. The results showed carbapenems (meropenem and imipenem) to be uniformly more potent in vitro than any other drug against the Enterobacteriaceae. Quinolone antibiotics were more active in vitro than aminoglycosides against a range of bacteria. Gram-negative bloodstream isolates were highly resistant to many antimicrobial agents in the hospital. In order to prevent hospital infection and antimicrobial resistance, surveillance of aetiological agents must be performed regularly.

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.

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 susceptibility of hazard analysis critical control point Escherichia coli isolates from federally inspected beef processing plants in Alberta, Saskatchewan, and Ontario.

PubMed

Van Donkersgoed, Joyce; Manninen, Ken; Potter, Andy; McEwen, Scott; Bohaychuk, Valerie; Klashinsky, Sandy; Deckert, Anne; Irwin, Rebecca

2003-09-01

A survey to estimate the prevalence of antimicrobial resistance in Escherichia coli was conducted in 7 Canadian federally inspected processing plants during 2001. Escherichia coli isolates were recovered during routine hazard analysis critical control point sampling from beef carcasses and trim and subsequently tested for their antimicrobial susceptibility by using susceptibility panels. Of the 2653 isolates analyzed, 68% were sensitive to all 18 antimicrobials tested. For 14 of the 18 antimicrobials evaluated, the percentage of resistant isolates was < or = 1. Twenty-five percent of the isolates were resistant to tetracycline, 9% to sulfamethoxazole, 7% to streptomycin, and 3% to ampicillin. Multiple resistance was found in 12% of the isolates, with 7% showing resistance to 2 antimicrobials, 2% to 3 antimicrobials, 2% to 4 antimicrobials, and 1% to 5 or more antimicrobials. Forty-five different antimicrobial resistance patterns were observed. The reasons for the development of the antimicrobial resistance were not investigated in this study. This study was useful as a pilot to help to develop a national antimicrobial resistance surveillance program in Canada. This study indicates that laboratory standardization is possible for consistent results across the country and that the indicator organism, E. coli, is fairly easy to obtain for surveillance but Salmonella are not, due to their low prevalence in beef.

Antimicrobial susceptibility of hazard analysis critical control point Escherichia coli isolates from federally inspected beef processing plants in Alberta, Saskatchewan, and Ontario

PubMed Central

Van Donkersgoed, Joyce; Manninen, Ken; Potter, Andy; McEwen, Scott; Bohaychuk, Valerie; Klashinsky, Sandy; Deckert, Anne; Irwin, Rebecca

2003-01-01

A survey to estimate the prevalence of antimicrobial resistance in Escherichia coli was conducted in 7 Canadian federally inspected processing plants during 2001. Escherichia coli isolates were recovered during routine hazard analysis critical control point sampling from beef carcasses and trim and subsequently tested for their antimicrobial susceptibility by using susceptibility panels. Of the 2653 isolates analyzed, 68% were sensitive to all 18 antimicrobials tested. For 14 of the 18 antimicrobials evaluated, the percentage of resistant isolates was ≤ 1. Twenty-five percent of the isolates were resistant to tetracycline, 9% to sulfamethoxazole, 7% to streptomycin, and 3% to ampicillin. Multiple resistance was found in 12% of the isolates, with 7% showing resistance to 2 antimicrobials, 2% to 3 antimicrobials, 2% to 4 antimicrobials, and 1% to 5 or more antimicrobials. Forty-five different antimicrobial resistance patterns were observed. The reasons for the development of the antimicrobial resistance were not investigated in this study. This study was useful as a pilot to help to develop a national antimicrobial resistance surveillance program in Canada. This study indicates that laboratory standardization is possible for consistent results across the country and that the indicator organism, E. coli, is fairly easy to obtain for surveillance but Salmonella are not, due to their low prevalence in beef. PMID:14524625

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.

Diversity and antimicrobial susceptibility of oxytetracycline-resistant isolates of Stenotrophomonas sp. and Serratia sp. associated with Costa Rican crops.

PubMed

Rodríguez, C; Wachlin, A; Altendorf, K; García, F; Lipski, A

2007-12-01

To ameliorate the identification, evaluate the diversity, and determine the antimicrobial sensitivity of 19 oxytetracycline-resistant isolates of Stenotrophomonas sp. and Serratia sp. associated with Costa Rican crops. Phenotypical, chemotaxonomical, and molecular data allocated most isolates to the species Sten. maltophilia and Ser. marcescens. The API profiles, antimicrobial resistance patterns (ATB system), and BOX-polymerase chain reaction (PCR) genomic fingerprints of isolates of Stenotrophomonas sp. exhibited a higher degree of heterogeneity than those obtained for the isolates of Serratia sp. The former group of bacteria exhibited multiresistance to antimicrobials. In contrast, isolates of Serratia sp. were sensitive to the majority of the drugs tested. Changes in the results of the antibiograms throughout incubation, which indicate an induction of tolerance, were observed for isolates of both the species. Minimum inhibitory concentration of oxytetracycline, determined using E-test stripes, were rather elevated. The occurrence of two species of opportunistic pathogens in crop-associated materials poses a risk to consumers in the community. The phenotypic and genotypic data presented could support epidemiologist and physicians dealing with infections caused by environmental strains of these taxa.

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.

Morphological, biochemical, physiological and molecular aspects of the response of Fusobacterium nucleatum exposed to subinhibitory concentrations of antimicrobials.

PubMed

de Souza Filho, Job Alves; Diniz, Cláudio Galuppo; Barbosa, Natália Bento; de Freitas, Michele Cristine Ribeiro; Lopes Neves, Mariana Silva; da Gama Mazzei, Rafaella Nogueira; Gameiro, Jacy; Coelho, Cíntia Marques; da Silva, Vânia Lúcia

2012-12-01

Subinhibitory concentrations (SICs) of antimicrobials may result in alterations in bacterial biology with implications for its potential aggression. This has considerable importance for the resident microbiota. Our aim was to analyze the effects of SICs of antimicrobials on the morphological, biochemical, physiological and molecular characteristics of the resident anaerobic Fusobacterium nucleatum. Fourteen strains were obtained from F. nucleatum ATCC 25586, selected by culturing on SICs of ampicillin, ampicillin/sulbactam, clindamycin, chloramphenicol, levofloxacin, metronidazole and piperacillin/tazobactam and subsequent culturing in the absence of drugs. Antimicrobial susceptibility, bacterial morphology, biochemical profiles and biofilm formation were evaluated. Genotyping and analysis of protein profiles were also performed. The antimicrobial susceptibility patterns showed that most of the derived strains were less sensitive to the antimicrobials, even after culturing them without drugs. Morphological and cell complexity alterations were observed, mainly in strains grown in SICs of β-lactam; these strains also expressed a reduced ability for biofilm formation. The other strains showed an increase in biofilm formation but no apparent morphological changes. Alterations were observed in the carbohydrate metabolism patterns and in the activity of microbial enzymes. Several proteins were positively or negatively regulated and there was polymorphism in the DNA from all derived strains. Therefore, SICs of antimicrobials induce alterations in F. nucleatum, which directly impact its biology. These results emphasize the risk of inadequate antibioticotherapy, which may have serious implications for clinical microbiology and infectious diseases and also may interfere with the host-bacteria relationship. Copyright © 2012 Elsevier Ltd. All rights reserved.

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.

A survey of veterinary antimicrobial prescribing practices, Washington State 2015.

PubMed

Fowler, H; Davis, M A; Perkins, A; Trufan, S; Joy, C; Buswell, M; McElwain, T F; Moore, D; Worhle, R; Rabinowitz, P M

2016-12-24

Antimicrobial resistance is a growing global health issue. It is also a recognised problem in veterinary medicine. Between September and December 2015 the authors administered a cross-sectional survey to licensed veterinarians in Washington State to assess factors affecting antimicrobial prescribing practices among veterinarians in Washington State. Two hundred and three veterinarians completed the survey. The majority of respondents (166, 82 per cent) were engaged in small animal or exotic animal practice. 24 per cent of respondents reported not ordering culture and sensitivity (C/S) testing in practice. Of the 76 per cent of veterinarians who reported ordering C/S tests, 36 per cent reported ordering such testing 'often' or 'always' when treating presumptive bacterial infections. Most respondents (65 per cent) mentioned cost as the most common barrier to ordering a C/S test. Only 16 (10 per cent) respondents reported having access to or utilising a clinic-specific antibiogram. This survey demonstrated that while antimicrobials are commonly used in veterinary practice, and veterinarians are concerned about antimicrobial resistance, cost is a barrier to obtaining C/S tests to guide antimicrobial therapy. Summaries of antimicrobial resistance patterns are rarely available to the practising veterinarian. Efforts to promote antimicrobial stewardship in a 'One Health' manner should address barriers to the judicious use of antimicrobials in the veterinary practice setting. British Veterinary Association.

Four-year analysis of microbial aetiology and antimicrobial sensitivity patterns of peritoneal-dialysis related peritonitis in a tertiary care facility.

PubMed

Persy, B; Ieven, M

2013-01-01

Peritonitis related to peritoneal dialysis increases morbidity and mortality and is the main reason for switching to haemodialysis. In this study, we analysed the dialysate of 164 peritoneal dialysis patients that was sent to our laboratory between January 2005 and August 2009. There were 196 peritonitis episodes identified in 78 patients. For all episodes, microbial aetiologies and in-vitro antimicrobial sensitivities were determined in addition to parameters such as the leukocyte count (WBC) and the result of the Gram stain. Results in children were analysed separately because of previously described differences in aetiology. In both groups, Gram positives were most commonly isolated, followed by Gram negatives and fungi or yeasts. In children, the proportion of coagulase-negative staphylococci compared to S. aureus is smaller than in adults. Gram stain showed predominant morphotypes concordant with culture results in 28% of episodes. A significant difference in WBC count was found between culture-positive (mean=3117 x 10(9)/L) and culture-negative (mean=981 x 10(9)/L) episodes in adults (p=0.001). The WBC count in episodes caused exclusively by CNS (mean=1502x10(9)/L) was also on average significantly lower (p=0.001) compared to all culture positive episodes. Resistance to methicillin was registered in 33% of cultures, positive for staphylococci. All Gram-positives were sensitive to vancomycin. Coverage of Gram-negatives by ceftazidim and quinolones was excellent (89%). Based on local sensitivity data and known characteristics of antimicrobials, a first-line empirical combination of intraperitoneal vancomycin with orally administered ciprofloxacin seems indicated in our population. Pathogens of positive aerobic cultures were sensitive in-vitro to their combined antimicrobial effect in 90% of cases.

Isolation, identification and antimicrobial sensitivity of Ornithobacterium rhinotracheale in broilers chicken flocks of Khuzestan, Iran

PubMed Central

Mayahi, Mansour; Gharibi, Darioush; Ghadimipour, Rahim; Talazadeh, Forough

2016-01-01

Ornithobacterium rhinotracheale (ORT) is a bacterium associated with respiratory disease, growth retardation, decreased egg production and mortality in chickens and turkeys. The objective of this study was isolation, identification and evaluation of antimicrobial susceptibility of ORT bacterium in slaughtered broilers chicken flocks based on cultural and molecular tests in Khuzestan province, south-west of Iran. A total of 210 tracheal swab samples were collected from 21 broiler flocks slaughtered in abattoirs of the province. The results of cultural and biochemical tests showed that 23 (10.95%) isolates from tracheal swabs of 4 flocks (19.04%) were identified as ORT, but according to molecular characterization, 18 (8.57%) ORT isolates were positive in PCR assay and produced the predicted 784 bp amplification product. Finally, using the disk diffusion method, the drug resistance patterns of ORT isolates were determined against a panel of commonly used antimicrobial agents. Antimicrobial susceptibility test revealed that all isolates (100%) were sensitive to tetracycline, florfenicol and cephalexin. The highest antimicrobial resistance (89.00%) was seen for fosfomycin, sultrim and gentamicin. The results of present research showed that there was significant difference between the isolation rates of ORT from various areas of the province. As well, our findings indicated that the simultaneous use of both cultural and molecular techniques results in more comprehensive outcomes in the isolation and identification of the organismfrom understudy hosts. PMID:28144427

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.

[Asymptomatic bacteruiria frequency in pregnant women and uropathogen in vitro antimicrobial sensitivity].

PubMed

Hernández Blas, Fernanda; López Carmona, Juan Manuel; Rodríguez Moctezuma, José Raymundo; Peralta Pedrero, María Luisa; Rodríguez Gutiérrez, Román Salvador; Ortiz Aguirre, Alma Rosa

2007-06-01

To estimate the frequency of asymptomatic bacteriuria in pregnant women attended in Family Medicine Units of the Instituto Mexicano del Seguro Social and to determine the in vitro sensitivity rate of the microorganisms to ampicillin, trimethoprim-sulfamethoxazole, nitrofurantoin and amikacin. We carried out an observational, prospective and transversal study at Family Medicine Units 62 and 64 of the Mexico State Delegation, located in the urban area of Mexico City. Women with lesser than 32 weeks of pregnancy without urinary tract symptoms were included. Urine culture of a midstream urine specimen with > or = 10(5) colony forming units/mL urine of an only germen was used as the gold standard. The in vitro antimicrobial sensitivity was established according to the Bauer Kirby technique. 874 pregnant women were included and 73 had a positive urine culture, with a frequency of 8.4%, IC 95% = 6.6 - 10.2%, of asymptomatic bacteriuria. Escherichia coil was the most frequent isolated agent (77%). In vitro sensitivity to ampicillin of the microorganisms isolated was of 27%, IC 95% = 16 - 38%; to trimethoprim-sulfamethoxazole of 40%, IC95% = 29 - 51%; to amikacin of 68%, IC 95% = 57 - 79%, and to nitrofurantoin of 79%, IC 95% = 70 - 88%. The frequency of asymptomatic bacteriuria in the studied population is similar to the reported by the literature. The in vitro sensitivity rates of E. coil to ampicillin and to trimethoprim-sulfamethoxazole are very low. The best sensitivity corresponded to the nitrofurantoin. The treatment of the asymptomatic bacteriuria must be based on the local patterns of antimicrobial sensitivity and resistance.

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.

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.

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.

Nasopharyngeal swabs of school children, useful in rapid assessment of community antimicrobial resistance patterns in Streptococcus pneumoniae and Haemophilus influenzae.

PubMed

Lalitha, M K; David, Thambu; Thomas, Kurien

2013-01-01

The present study evaluates the feasibility of rapid surveillance of community antimicrobial resistance (AMR) patterns of Streptococcus pneumoniae and Haemophilus influenzae in India using nasopharyngeal swabs (NPSs) of school children. It compares the AMR data obtained with that of invasive and nasopharyngeal (NP) isolates studied previously. No one has done such surveillance since our study so we decided to publish and more clearly demonstrate the feasibility of the methodology we did. This community-based, cross-sectional, cluster sample study had seven centers; each had two sites distant to them. Two hundred sixty school children per center were enrolled. NP swabbing was performed and isolates identified as S. pneumoniae and H. influenzae at each center were sent to reference laboratories. From January to December 2004, 1,988 NP swabs were processed; 776 S. pneumoniae and 64 H. influenzae were isolated. The AMR patterns for S. pneumoniae to co-trimoxazole varied, with sensitivity as low as 6% in Mumbai, 29% in Chennai and Vellore, and 100% in Delhi and Lucknow. For H. influenzae, sensitivity rates to co-trimoxazole ranged from 22% to 62%. The AMR patterns for both bacteria in the present study with data from invasive and NP isolates studied earlier were similar. The study demonstrates that it is practical and feasible to rapidly assess the AMR patterns of both S. pneumoniae and H. influenzae in NPSs of school children in different geographic locations all over India. Copyright © 2013 Elsevier Inc. All rights reserved.

ANTIMICROBIAL SENSITIVITY PATTERNS OF MAJOR ZOONOTIC PATHOGENS FROM A SEASON-LONG “FARM-TO-FORK” STUDY OF ALL NATURAL, ANTIBIOTIC-FREE, PASTURE-RAISED BROILER FLOCKS IN THE SOUTHEASTERN UNITED STATES

USDA-ARS?s Scientific Manuscript database

Introduction: The prevalence of antibiotic resistance microorganisms has significant implications for environmental, animal, and human health. One focus is the use of antibiotics in animal agriculture and its effects on antibiotic resistant bacterial populations within those systems, but before thi...

ANTIMICROBIAL SENSITIVITY PATTERNS OF MAJOR ZOONOTIC PATHOGENS FROM A SEASON-LONG “FARM-TO-FORK” STUDY OF ALL NATURAL, ANTIBIOTIC-FREE, PASTURE-RAISED BROILER FLOCKS IN THE SOUTHEASTERN UNITED STATES

USDA-ARS?s Scientific Manuscript database

Background: The prevalence of antibiotic resistance microorganisms has significant implications for environmental, animal, and human health. One focus is the use of antibiotics in animal agriculture and its effects on antibiotic resistant bacterial populations within those systems, but before this ...

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.

Antimicrobial susceptibility patterns of enterobacteriaceae isolated from HIV-infected patients in Kinshasa.

PubMed

Iyamba, Jean-Marie Liesse; Wambale, José Mulwahali; Takaisi-Kikuni, Ntondo Za Balega

2014-01-01

People infected by Human Immunodeficiency Virus (HIV) are susceptible to develop severe bacterial infections. We set out to determine the frequency and the sensitivity to antibiotics of enterobaceriaceae isolated from urine and feces of HIV-infected persons. Urine and feces samples were collected from HIV-infected patients of the Centre de Traitement Ambulatoire de Kabinda (CTA/Kabinda, Kinshasa) and analyzed at the Reference National Laboratory for HIV/AIDS and Sexually Transmitted Infections. The isolated enterobacteriaceae strains were identified by conventional microbiological methods. Antibiotic sensitivity pattern was carried out by disc diffusion method. THE FOLLOWING BACTERIA PATHOGENS WERE ISOLATED: Escherichia coli, Klebsiella, Enterobacter, Proteus, and Providencia. Most species were sensitive to cefotaxim, ceftriaxon, and gentamicin and resistant to chloramphenicol, cotrimoxazole, tetracycline, and norfloxacin. The results of the present study show that the most frequently bacteria isolated were Esherichia coli and cefotaxim, ceftriaxon, and gentamicin were the most active antibiotics.

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

Evaluation of the Premi Test and comparison with the One-Plate Test for the detection of antimicrobials in kidney.

PubMed

Cantwell, H; O'Keeffe, M

2006-02-01

The Premi Test, a test kit designed for the rapid screening of antimicrobial residues in meat, fish and eggs, was evaluated and compared with the (modified) One-Plate Test, an agar diffusion assay. The performance characteristics described for qualitative, screening methods in Commission Decision 2002/657/EC were used for the evaluation. The Premi Test was found to detect a range of antimicrobials to MRL levels in kidney fluid but to have poorer sensitivity for some antimicrobials such as tetracyclines, sulphonamides, flumequine and streptomycin. The test was found not to be sensitive for the banned antimicrobial chloramphenicol. The One-Plate Test was found to detect most tetracyclines and flumequine to MRL levels but to be less sensitive than the Premi Test for most of the other classes of antimicrobials. Neither test alone provides a comprehensive screening test for antimicrobial residues in kidney at MRL levels. However, the Premi Test is fast, easy to use and rugged and, in combination with other antimicrobial tests, may be used to provide a comprehensive screening system for antimicrobials in tissues.

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.

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 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.

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.

Emergence of Stenotrophomonas maltophilia nosocomial isolates in a Saudi children's hospital. Risk factors and clinical characteristics.

PubMed

Alqahtani, Jobran M

2017-05-01

  To describe the clinical characteristics of pediatric patients colonized or infected by Stenotrophomonas maltophilia (S. maltophilia) at a Saudi children's hospital, to identify risk factors associated with infection, and to investigate the antimicrobial resistance patterns of this emerging pathogen.  Methods: In this cross-sectional observational study, 64 non-duplicating S. maltophilia strains were isolated  in Najran Maternity and Children's Hospital, Najran,  Saudi Arabia between January 2015 to February 2016. Antimicrobial susceptibility testing was performed using the reference broth microdilution method.  Results: In this study, 48 (75%) isolates were identified in true infections and 16 (25%) isolates were considered colonization. The main types of S. maltophilia infection were pneumonia in 22 (45.8%) patients and bloodstream infection in 14 (29.2%) patients. The significant risk factors included exposure to invasive procedure (p=0.02), and presence of acute leukemia as an underlying disease (p=0.02). The most active antimicrobials were trimethoprim/sulfamethoxazole (100% sensitivity) and tigecycline (93.7% sensitivity). Conclusions: Stenotrophomonas maltophilia is an emerging nosocomial pathogen among pediatric patients. Accurate identification and susceptibility testing of this emerging pathogen are crucial for the management of infected patients and prevention of spread of this nosocomial pathogen.

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.

Antibacterial activity of the soil-bound antimicrobials oxytetracycline and ofloxacin.

PubMed

Peng, Feng-Jiao; Zhou, Li-Jun; Ying, Guang-Guo; Liu, You-Sheng; Zhao, Jian-Liang

2014-04-01

Soil contamination of antimicrobials has become an increasing concern because of the potential risks to the soil microbial ecosystem and human health. The present study investigated sorption and desorption behaviors of oxytetracycline (OTC) and ofloxacin (OFL) in 3 typical soils (A, B, and C), and evaluated the antibacterial activity of soil-adsorbed compounds to a pure sensitive strain Escherichia coli ATCC 25922. The results showed different sorption and desorption behaviors of OTC and OFL in the 3 soils, behaviors that were mainly influenced by soil organic matter content and cation exchange capacity (CEC) as well as pH value. In addition, complexation and cation-exchange reactions were shown to be the main sorption mechanisms. Strong adsorption was found in soil B (with a high organic matter content) and in soil C (with high CEC), whereas enhanced desorption was observed in soil A (with low organic matter content). The results also demonstrated that soil-bound antimicrobials retained antibacterial activity toward E. coli. Opposite patterns of antibacterial activity were found for the 2 antimicrobials in the 3 soils: A>B>C for OFL; and C>B>A for OTC. This finding suggests that soil-bound antimicrobials could still exert selective pressure on soil bacteria although less effectively in comparison with the dissolved forms. © 2014 SETAC.

Temporal variations in patterns of Escherichia coli strain diversity and antimicrobial resistance in the migrant Egyptian vulture

PubMed Central

Maherchandani, Sunil; Shringi, B. N.; Kashyap, Sudhir Kumar

2018-01-01

ABSTRACT Aims: Multiple antimicrobial resistance in Escherichia coli of wild vertebrates is a global concern with scarce assessments on the subject from developing countries that have high human-wild species interactions. We studied the ecology of E. coli in a wintering population of Egyptian Vultures in India to understand temporal changes in both E. coli strains and patterns of antimicrobial resistance. Methods and Results: We ribotyped E. coli strains and assessed antimicrobial resistance from wintering vultures at a highly synanthropic carcass dump in north-west India. Both E. coli occurence (90.32%) and resistance to multiple antimicrobials (71.43%) were very high. Clear temporal patterns were apparent. Diversity of strains changed and homogenized at the end of the Vultures’ wintering period, while the resistance pattern showed significantly difference inter-annually, as well as between arrival and departing individuals within a wintering cycle. Significance of study: The carcass dump environment altered both E. coli strains and multiple antimicrobial resistance in migratory Egyptian Vultures within a season. Long-distance migratory species could therefore disseminate resistant E. coli strains across broad geographical scales rendering regional mitigation strategies to control multiple antimicrobial resistance in bacteria ineffective. PMID:29755700

Preliminary study on the antimicrobial susceptibility pattern related to the genotype of Vibrio vulnificus strains isolated in the north-western Adriatic Sea coastal area.

PubMed

Serratore, Patrizia; Zavatta, Emanuele; Fiocchi, Eleonora; Serafini, Emanuele; Serraino, Andrea; Giacometti, Federica; Bignami, Giorgia

2017-10-20

V. vulnificus is a Gram-negative bacterium, commonly found in estuarine and coastal habitats, that can infect humans through seafood consumption or wound exposure. This study represents the first attempt to correlate the genotype of Vibrio vulnificus strains isolated in the north-western Adriatic Sea coastal area, with their antimicrobial susceptibility patterns. On the whole, 40 V. vulnificus strains, isolated from shellfish (n=20), different coastal water bodies (n=19), and the blood of a Carretta carretta turtle (n=1), were utilized. All strains were positive for the species-specific genes vvh A and hsp , with high variability for other markers: 55% (22 out of 40) resulted of the environmental (E) genotype ( vcg E, 16S rRNA type A, CPS2 or CPS0), 10% (4 out of 40) of the clinical (C) genotype ( vcg C, 16S rRNA type B, CPS1), and 35% (14 out of 40) of the mixed (M) genotype, possessing both E and C markers. The antimicrobial susceptibility was assayed by the diffusion method on agar, according to the Clinical Laboratory Standards Institute (CLSI), utilizing the following commercial disks (Oxoid): ampicillin (AMP), ampicillin- sulbactam (SAM), piperacillin (PRL), cefazolin (KZ), cefotaxime(CTX), ceftazidime (CAZ), imipenem (IPM), meropenem (MEM), amikacin (AK), gentamicin(CN), tetracycline(TE), ciprofloxacin (CIP), levofloxacin (LEV), trimethoprim-sulfamethoxazole (SXT), and chloramphenicol (C). 75% of the strains, (n=30) including all C strains, was sensitive to all the tested antibiotics, whereas E strains showed intermediate sensitivity to AK (2 strains), CIP and CAZ (1 strain), TE (1 strain) and resistance to KZ (1 strain), and 4 M strains showed I to AK.

Asymtomatic bacteriuria in pregnancy: assesment of prevlence, microbial agents and ther antimicrobial sensitivty pattern in Gondar Teaching Hospital, north west Ethiopia.

PubMed

Tadesse, Abilo; Negash, Mekonnen; Ketema, Late Shimeles

2007-04-01

To estimate the prevalence of asymptomatic bacteriuria in pregnant women, identify the frequently isolated uropathogenic bacteria and its antimicrobial sensitivity pattern. This cross-sectional case series study was conducted in antenatal care clinic of Gondar Teaching Hospital from June-Oct., 2001. One hundred and seventy three pregnant women, who met the inclusion criteria, were included in the study after informed consent was obtained Clinical information pertaining to socio demographic data and obstetric history was filled in the questionnaire, pertinent physical examination was done and urine specimen from each candidate was collected and processed following the standard microbiological technique. Majority (70-90%) of the pregnant women were literate, housewives, married and residents of Gondar town. Of all pregnant women included in the study, 96/173 (56%) were multigravida, and 21/173 (12%) had 5 or more pregnancies. The identification rate of significant bacteriuria in the study group was 9.8% (17/173) with higher rate (20.5%) in multiparous mothers. The frequently isolated urinary pathogenic bacteria was E. coli, 47% (8/17), followed by S. aureus 3/17 (18%) and C. freundi 2/17 (12%). The majority of E. coli isolates (50-75%) were resistant to gentamicin, Ampicillin, trimethoprim-sulphamethoxazole, tetracycline, and chloramphenicol; while 75% and 100% of E. coli isolates were sensitive to cefoxitin, and ciprofloxacin respectively. Asymptomatic bacteriuria in pregnant women was prevalent in the study locality. E. coli was the common isolated urinary pathogen among urine samples of study subjects, and was found to be resistant to multiple antimicrobial agents. We suggest cefoxitin should be the drug used to treat significant bacteriuria in pregnant women in the study locality.

Antimicrobial susceptibility pattern in nosocomial infections caused by Acinetobacter species in Asir Region, Saudi Arabia.

PubMed

Abdalla, Nazar M; Osman, Amani A; Haimour, Waleed O; Sarhan, Mohammed A A; Mohammed, Mohammed N; Zyad, Eyhab M; Al-Ghtani, Abdalla M

2013-03-15

This study aimed at evaluating the sensitivity of antibiotics towards nosocomial infections caused by Acinetobacter species. The study took place during the period Dec. 2011- Dec. 2012 at Assir Central Hospital in collaboration with the department of microbiology, college of medicine, King Khalid University, Abha. A prospective study involving 150 patients presented with nosocomial infections due to Acinetobacter species detected by bacteriological tests; direct microscopy, culture in blood agar media, fermentation test in MacConkey media and MIC (minimum inhibitory concentration) for antibiotics sensitivity using Muller Hinton media and Chemical test using API 20. A 150 nosocomial infections in this study showed gram-negative coccobacilli, non motile, glucose-negative fermentor and oxidase negative. All isolates showed 100% sensitivity to: Imipramine, Meropenem, Colistin. From the rest of tested antibiotics the higher resistant ones were; Nitrofurantoin 87% and Cefoxitin 85%. The least resistant antibiotics; Imipenem 3% and Ticarcillin 7%. While variable resistance in the rest of tested antimicrobials. A 47 patients (31.3%) have used antibiotics prior to this study. The high rate of usage occurred in elder patients. The frequency of Acinetobacter calcoaceticus baumannii complex multi-drugs resistance ABCMDR is rising including almost all commonly used antibiotics. Only few antibiotics exert 100% sensitivity towards these bacteria.

Antibiotic resistance pattern among the Salmonella isolated from human, animal and meat in India.

PubMed

Singh, Shweta; Agarwal, Rajesh Kumar; Tiwari, Suresh C; Singh, Himanshu

2012-03-01

The present study was conducted to study the antibiotic resistance pattern among nontyphoidal Salmonella isolated from human, animal and meat. A total of 37 Salmonella strains isolated from clinical cases (human and animal) and meat during 2008-2009 belonging to 12 serovars were screened for their antimicrobial resistance pattern using 25 antimicrobial agents falling under 12 different antibiotic classes. All the Salmonella isolates tested showed multiple drug resistance varying from 5.40% to 100% with 16 of the 25 antibiotics tested. None of the isolates were sensitive to erythromycin and metronidazole. Resistance was also observed against clindamycin (94.59%), ampicillin (86.49%), co-trimoxazole (48.65%), colistin (45.94%), nalidixic acid (35.10%), amoxyclave (18.90%), cephalexin, meropenem, tobramycin, nitrofurantoin, tetracycline, amoxicillin (8.10% each), sparfloxacin and streptomycin (5.40% each). Isolates from clinical cases of animals were resistant to as many as 16 antibiotics, whereas isolates from human clinical cases and meat were resistant to 9 and 14 antibiotics, respectively. Overall, 19 resistotypes were recorded. Analysis of multiple antibiotic resistance index (MARI) indicated that clinical isolates from animals had higher MARI (0.25) as compared to isolates from food (0.22) and human (0.21). Among the different serotypes studied for antibiogram, Paratyhi B isolates, showed resistance to three to 13 antibiotics, whereas Typhimurium strains were resistant to four to seven antibiotics. Widespread multidrug resistance among the isolates from human, animal and meat was observed. Some of the uncommon serotypes exhibited higher resistance rate. Considerable changes in the resistance pattern were also noted. An interesting finding was the reemergence of sensitivity to some of the old antibiotics (chloromphenicol, tetracycline).

Time-patterns of antibiotic exposure in poultry production--a Markov chains exploratory study of nature and consequences.

PubMed

Chauvin, C; Clement, C; Bruneau, M; Pommeret, D

2007-07-16

This article describes the use of Markov chains to explore the time-patterns of antimicrobial exposure in broiler poultry. The transition in antimicrobial exposure status (exposed/not exposed to an antimicrobial, with a distinction between exposures to the different antimicrobial classes) in extensive data collected in broiler chicken flocks from November 2003 onwards, was investigated. All Markov chains were first-order chains. Mortality rate, geographical location and slaughter semester were sources of heterogeneity between transition matrices. Transitions towards a 'no antimicrobial' exposure state were highly predominant, whatever the initial state. From a 'no antimicrobial' exposure state, the transition to beta-lactams was predominant among transitions to an antimicrobial exposure state. Transitions between antimicrobial classes were rare and variable. Switches between antimicrobial classes and repeats of a particular class were both observed. Application of Markov chains analysis to the database of the nation-wide antimicrobial resistance monitoring programme pointed out that transition probabilities between antimicrobial exposure states increased with the number of resistances in Escherichia coli strains.

Fosfomycin: An Alternative Therapy for the Treatment of UTI Amidst Escalating Antimicrobial Resistance.

PubMed

Sabharwal, Ekadashi Rajni; Sharma, Rajni

2015-12-01

Urinary tract infections (UTIs) are the most commonly encountered infectious diseases. The current study was undertaken with a dual purpose, to provide an insight into the current scenario of the microorganisms causing UTI, their antimicrobial sensitivity patterns and also try and evaluate the activity of fosfomycin against E. coli, both ESBL producers as well as non-producers. The study was conducted prospectively in the Department of Microbiology of a tertiary care hospital from January to June 2014. A total of 358 isolates from the urinary samples of the patients with a diagnosis of urinary tract infection were included in the study. Antibiotic sensitivity testing and extended spectrum beta lactamase (ESBL) production testing was done as per CLSI guidelines. These represented 297 (82.9%) gram-negative isolates and 61 (17%) gram-positive isolates. The 297 gram-negative isolates represented 265 (89.2%) members of the Enterobacteriaceae, 185 (69.8%) of which were Escherichia coli, 66 (24.9%) Klebsiella spp. and 14 (5.28%) Proteus spp. Non-fermentative Pseudomonas spp were isolated from 8.9% cases. Amongst the Gram negative isolates tested, 78 (21.8%) formed extended spectrum beta-lactamases. Of the total 358 isolates tested, 338 (94.4%) were found to be susceptible to fosfomycin. Fosfomycin showed good activity against both ESBL-producing and ESBL-negative E. coli isolates. The main finding of our study is that fosfomycin exhibits excellent antimicrobial activity even against the isolates with relatively high levels of antimicrobial resistance and hence can be a useful drug in our armamentarium.

Identification and antimicrobial resistance of microflora colonizing feral pig (Sus scrofa) of Brazilian Pantanal.

PubMed Central

Lessa, SS; Paes, RCS; Santoro, PN; Mauro, RA; Vieira-da-Motta, O

2011-01-01

Antimicrobial resistance of bacteria is a worldwide problem affecting wild life by living with resistant bacteria in the environment. This study presents a discussion of outside factors environment on microflora of feral pigs (Sus scrofa) from Brazilian Pantanal. Animals had samples collected from six different body sites coming from two separated geographic areas, Nhecolandia and Rio Negro regions. With routine biochemical tests and commercial kits 516 bacteria were identified, with 240 Gram-positive, predominantly staphylococci (36) and enterococci (186) strains. Among Gram-negative (GN) bacteria the predominant specimens of Enterobacteriaceae (247) mainly represented by Serratia spp. (105), Escherichia coli (50), and Enterobacter spp. (40) and specimens not identified (7). Antimicrobial susceptibility was tested against 17 drugs by agar diffusion method. Staphylococci were negative to production of enterotoxins and TSST-1, with all strains sensitive towards four drugs and highest resistance toward ampicillin (17%). Enterococci presented the highest sensitivity against vancomycin (98%), ampicillin (94%) and tetracycline (90%), and highest resistance pattern toward oxacillin (99%), clindamycin (83%), and cotrimoxazole (54%). In GN the highest resistance was observed with Serratia marcescens against CFL (98%), AMC (66%) and AMP (60%) and all drugs was most effective against E. coli SUT, TET (100%), AMP, TOB (98%), GEN, CLO (95%), CFO, CIP (93%). The results show a new profile of oxacillin-resistant enterococci from Brazilian feral pigs and suggest a limited residue and spreading of antimicrobials in the environment, possibly because of low anthropogenic impact reflected by the drug susceptibility profile of bacteria isolated. PMID:24031689

The Risk of Some Veterinary Antimicrobial Agents on Public Health Associated with Antimicrobial Resistance and their Molecular Basis

PubMed Central

Hao, Haihong; Sander, Pascal; Iqbal, Zahid; Wang, Yulian; Cheng, Guyue; Yuan, Zonghui

2016-01-01

The risk of antimicrobial agents used in food-producing animals on public health associated with antimicrobial resistance continues to be a current topic of discussion as related to animal and human public health. In the present review, resistance monitoring data, and risk assessment results of some important antimicrobial agents were cited to elucidate the possible association of antimicrobial use in food animals and antimicrobial resistance in humans. From the selected examples, it was apparent from reviewing the published scientific literature that the ban on use of some antimicrobial agents (e.g., avoparcin, fluoroquinolone, tetracyclines) did not change drug resistance patterns and did not mitigate the intended goal of minimizing antimicrobial resistance. The use of some antimicrobial agents (e.g., virginiamycin, macrolides, and cephalosporins) in food animals may have an impact on the antimicrobial resistance in humans, but it was largely depended on the pattern of drug usage in different geographical regions. The epidemiological characteristics of resistant bacteria were closely related to molecular mechanisms involved in the development, fitness, and transmission of antimicrobial resistance. PMID:27803693

40 CFR 158.2201 - Antimicrobial use patterns.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... (10) Wood preservatives. (11) Swimming pools. (12) Aquatic areas. (b) Use site index. The Pesticide Use Site Index for Antimicrobial Pesticides is a comprehensive list of specific antimicrobial use sites. The Index associates antimicrobial use sites with one or more of the 12 antimicrobial use...

40 CFR 158.2201 - Antimicrobial use patterns.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... (10) Wood preservatives. (11) Swimming pools. (12) Aquatic areas. (b) Use site index. The Pesticide Use Site Index for Antimicrobial Pesticides is a comprehensive list of specific antimicrobial use sites. The Index associates antimicrobial use sites with one or more of the 12 antimicrobial use...

A Comparison of Non-Typhoidal Salmonella from Humans and Food Animals Using Pulsed-Field Gel Electrophoresis and Antimicrobial Susceptibility Patterns

PubMed Central

Sandt, Carol H.; Fedorka-Cray, Paula J.; Tewari, Deepanker; Ostroff, Stephen; Joyce, Kevin; M’ikanatha, Nkuchia M.

2013-01-01

Salmonellosis is one of the most important foodborne diseases affecting humans. To characterize the relationship between Salmonella causing human infections and their food animal reservoirs, we compared pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility patterns of non-typhoidal Salmonella isolated from ill humans in Pennsylvania and from food animals before retail. Human clinical isolates were received from 2005 through 2011 during routine public health operations in Pennsylvania. Isolates from cattle, chickens, swine and turkeys were recovered during the same period from federally inspected slaughter and processing facilities in the northeastern United States. We found that subtyping Salmonella isolates by PFGE revealed differences in antimicrobial susceptibility patterns and, for human Salmonella, differences in sources and invasiveness that were not evident from serotyping alone. Sixteen of the 20 most common human Salmonella PFGE patterns were identified in Salmonella recovered from food animals. The most common human Salmonella PFGE pattern, Enteritidis pattern JEGX01.0004 (JEGX01.0003ARS), was associated with more cases of invasive salmonellosis than all other patterns. In food animals, this pattern was almost exclusively (99%) found in Salmonella recovered from chickens and was present in poultry meat in every year of the study. Enteritidis pattern JEGX01.0004 (JEGX01.0003ARS) was associated with susceptibility to all antimicrobial agents tested in 94.7% of human and 97.2% of food animal Salmonella isolates. In contrast, multidrug resistance (resistance to three or more classes of antimicrobial agents) was observed in five PFGE patterns. Typhimurium patterns JPXX01.0003 (JPXX01.0003 ARS) and JPXX01.0018 (JPXX01.0002 ARS), considered together, were associated with resistance to five or more classes of antimicrobial agents: ampicillin, chloramphenicol, streptomycin, sulfonamides and tetracycline (ACSSuT), in 92% of human and 80% of food animal Salmonella isolates. The information from our study can assist in source attribution, outbreak investigations, and tailoring of interventions to maximize their impact on prevention. PMID:24204990

Resistance patterns in clinical isolates of pathogenic Actinomyces species.

PubMed

Steininger, C; Willinger, Birgit

2016-02-01

Actinomyces spp. are commensals that may occasionally invade deep tissue structures, causing difficult-to-treat and disfiguring lesions. Information on antimicrobial resistance patterns is limited to observations from two previous studies. Therefore, we examined antimicrobial resistance patterns in clinical isolates of Actinomyces spp. In this retrospective assessment of antimicrobial resistance patterns, we identified 392 Actinomyces spp. at a tertiary care centre from January 2008 to December 2014. MICs of various antimicrobial agents, including ampicillin/sulbactam, meropenem, clindamycin, metronidazole and vancomycin for anaerobic actinomycetes, were obtained by Etest. For aerobic actinomycetes, imipenem, cefotaxime, amikacin, linezolid, moxifloxacin, trimethoprim/sulfamethoxazole and clarithromycin were tested. MIC results were interpreted based on guidelines published by the CLSI (formerly NCCLS). Actinomyces meyeri was predominantly isolated and accounted for 34% of all Actinomyces spp. identified, followed by Actinomyces turicensis with 23%. Actinomyces neuii is considered to be a rare Actinomyces sp., but accounted for 8% of isolates. Antimicrobial susceptibility testing of isolates showed that the Actinomyces spp. were almost uniformly susceptible to β-lactam antimicrobials (with and without β-lactamase inhibitors), carbapenems, tetracyclines and vancomycin. In contrast, Actinomyces spp. isolates were almost uniformly resistant to metronidazole. β-Lactam antimicrobial agents remain the first choice, whereas metronidazole should be avoided, in the treatment of actinomycosis. Reasonable alternatives for treatment are tetracyclines and carbapenems. © The Author 2015. 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.

A review on Sero diversity and antimicrobial resistance patterns of Shigella species in Africa, Asia and South America, 2001-2014.

PubMed

Kahsay, Atsebaha Gebrekidan; Muthupandian, Saravanan

2016-08-30

Shigella, gram negative bacterium, is responsible for Shigellosis/bacillary dysentery. It is a global concern although it predominates in developing countries. These are Shigella dysenteriae, Shigella flexneri, Shigella boydii and Shigella sonnei. Drug resistance by Shigella species is another headache of the world. Therefore; this study aimed to review distribution of Shigella Serogroups and their antimicrobial patterns carried out in Africa, Asia and South America. A literature search was performed to identify published studies between January 2001 and December 2014. Published studies were identified using an initial search of the MEDLINE/Index Medicus Database, PubMed, Project Management Consultant, Google Scholar, Science Direct, BioMed Central and Index Copernicus. Shigella flexneri was isolated predominately from seven studies in four African countries and eight studies in five Asian countries. The countries in which eligible studies carried out were Ethiopia, Kenya, Eritrea and Ghana in Africa and Pakistan, Iran, China, Nepal and India in Asia. S. sonnei was isolated predominately from one study in Africa, four in Asia and two South America. The countries in which eligible studies carried out were Ethiopia from Africa, Thailand, Vietnam and Iran from Asia and Chile and Trinidad from South America. S. dysentery was also reported majorly from one eligible study in Egypt and one in Nepal. S. boydii did not score highest prevalence in any one of the eligible studies. Three studies from Africa, five from Asia and one from South America were reviewed for antimicrobial resistance patterns of Shigella Serogroups. In all the regions, Ampicillin developed highly resistance to almost all the Serogroups of Shigella whereas all the strains were sensitive to Ciprofloxacin. The incidence of Shigella Serogroups in the selected three regions is different. The domination of S. flexneri is observed in Africa and Asia although S. sonnei in South America is dominant. Shigella Serogroups are becoming resistance to the commonly prescribed antimicrobial drugs in developing countries.

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.

Medicinal chemistry discoveries among 1,3,5-triazines: recent advances (2000-2013) as antimicrobial, anti-TB, anti-HIV and antimalarials.

PubMed

Patel, Rahul V; Keum, Young-Soo; Park, Se Won

2014-01-01

The chemistry and an extensive spectrum of biological activities of s-triazines have been examined since several decades and this heterocyclic core has received emerging consensus. This article aims to summarize recent advances (2000-2013) made towards the discovery of antimicrobial, antituberculosis, anti-HIV and antimalarial agents holding 1,3,5-triazine ring as a nucleus with the substitution of several types of nucleophiles. Molecular patterns associated with particular potency have been identified targeting several Gram-positive and Gram-negative bacteria and some fungal species, mycobacterium tuberculosis H37Rv, HIV type I and HIV type II, particularly, HIV-1I IIB and HIV- 1ROD strains as well as a variety of P. falciparum malarial strains as chloroquine-resistant K1, chloroquine-susceptible NF54, chloroquine-sensitive 3D7, P. falciparum (D6 clone), P. falciparum (W2 clone), cycloguanil-resistant FCR-3, chloroquine sensitive RKL2. The report will be of considerable interest to gain useful information for the furtherance of drug discovery with extended 1,3,5-triazine designs.

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/.

The Value of Electronically Extracted Data for Auditing Outpatient Antimicrobial Prescribing.

PubMed

Livorsi, Daniel J; Linn, Carrie M; Alexander, Bruce; Heintz, Brett H; Tubbs, Traviss A; Perencevich, Eli N

2018-01-01

OBJECTIVE The optimal approach to auditing outpatient antimicrobial prescribing has not been established. We assessed how different types of electronic data-including prescriptions, patient-visits, and International Classification of Disease, Tenth Revision (ICD-10) codes-could inform automated antimicrobial audits. DESIGN Outpatient visits during 2016 were retrospectively reviewed, including chart abstraction, if an antimicrobial was prescribed (cohort 1) or if the visit was associated with an infection-related ICD-10 code (cohort 2). Findings from cohorts 1 and 2 were compared. SETTING Primary care clinics and the emergency department (ED) at the Iowa City Veterans Affairs Medical Center. RESULTS In cohort 1, we reviewed 2,353 antimicrobial prescriptions across 52 providers. ICD-10 codes had limited sensitivity and positive predictive value (PPV) for validated cases of cystitis and pneumonia (sensitivity, 65.8%, 56.3%, respectively; PPV, 74.4%, 52.5%, respectively). The volume-adjusted antimicrobial prescribing rate was 13.6 per 100 ED visits and 7.5 per 100 primary care visits. In cohort 2, antimicrobials were not indicated in 474 of 851 visits (55.7%). The antimicrobial overtreatment rate was 48.8% for the ED and 59.7% for primary care. At the level of the individual prescriber, there was a positive correlation between a provider's volume-adjusted antimicrobial prescribing rate and the individualized rates of overtreatment in both the ED (r=0.72; P<.01) and the primary care setting (r=0.82; P=0.03). CONCLUSIONS In this single-center study, ICD-10 codes had limited sensitivity and PPV for 2 infections that typically require antimicrobials. Electronically extracted data on a provider's rate of volume-adjusted antimicrobial prescribing correlated with the frequency at which unnecessary antimicrobials were prescribed, but this may have been driven by outlier prescribers. Infect Control Hosp Epidemiol 2018;39:64-70.

Urinary levels of triclosan and parabens are associated with aeroallergen and food sensitization

PubMed Central

Savage, Jessica H.; Matsui, Elizabeth C.; Wood, Robert A.; Keet, Corinne A.

2013-01-01

Background Endocrine-disrupting compounds (EDCs) have immune-modulating effects. We were interested in determining their association with allergic sensitization. Objective To determine the association between EDCs and allergic sensitization and if this relationship depended on the antimicrobial properties of the EDCs and/or gender. Methods Data were obtained from the 2005–2006 National Health and Nutrition Examination Survey in which urinary bisphenol A, triclosan, benzophenone-3, and propyl, methyl, butyl and ethyl paraben, and specific IgE were available on 860 children. Aeroallergen and food sensitization were defined as having at least one positive (≥0.35 kU/L) specific IgE to an aeroallergen or a food. Logistic regression was used to determine the association of EDCs and sensitization. Analyses were adjusted for urinary creatinine, age, ethnicity, and poverty index ratio. Results The odds of aeroallergen sensitization significantly increased with the level of the antimicrobial EDCs triclosan and propyl and butyl paraben (p≤0.04). The odds of food sensitization significantly increased with the level of urinary triclosan among male subjects (odds ratio for 3rd versus 1st tertile 3.9, p=0.02 for trend). There was a significant interaction between gender and triclosan, with males being more likely to be food sensitized with exposure (p=0.03). Similar associations were not identified for the non-antimicrobial EDCs bisphenol A and benzophenone-3 (p>0.2). Conclusions As a group, EDCs are not associated with allergen sensitization. However, levels of the antimicrobial EDCs triclosan and parabens were significantly associated with allergic sensitization. The potential role of antimicrobial EDCs in allergic disease warrants further study as they are commonly used in Western society. PMID:22704536

Sensitivity of soil microbial processes to livestock antimicrobials

USDA-ARS?s Scientific Manuscript database

Strong public concern that the overuse of livestock antimicrobials produce greater antibiotic resistance and pose a risk for human health have led to new regulations on the use of antimicrobials. Manure runoff containing trace levels of antimicrobials is usually applied to crop fields, but their im...

[Analysis on the antimicrobial resistance of lactic acid bacteria isolated from the yogurt sold in China].

PubMed

Fan, Qin; Liu, Shuliang; Li, Juan; Huang, Tingting

2012-05-01

To analyze the antimicrobial susceptibility of lactic acid bacteria (LAB) from yogurt, and to provide references for evaluating the safety of LAB and screening safe strains. The sensitivity of 43 LAB strains, including 14 strains of Streptococcus thermophilus, 12 strains of Lactobacillus acidophilus, 9 strains of Lactobacillus bulgaricus and 8 strains of Bifidobacterium, to 22 antibiotics were tested by agar plate dilution method. All 43 LAB strains were resistant to trimethoprim, nalidixic acid, ciprofloxacin, lomefloxacin, danofloxacin and polymyxin E. Their resistances to kanamycin, tetracycline, clindamycin, doxycycline and cephalothin were varied. The sensitivity to other antibiotics were sensitive or moderate. All isolates were multidrug-resistant. The antimicrobial resistance of tested LAB strains was comparatively serious, and continuously monitoring their antimicrobial resistance and evaluating their safety should be strengthened.

Patterns of antimicrobial agent prescription in a sentinel population of canine and feline veterinary practices in the United Kingdom.

PubMed

Singleton, D A; Sánchez-Vizcaíno, F; Dawson, S; Jones, P H; Noble, P J M; Pinchbeck, G L; Williams, N J; Radford, A D

2017-06-01

Antimicrobial resistance is an increasingly important global health threat and the use of antimicrobial agents is a key risk factor in its development. This study describes antimicrobial agent prescription (AAP) patterns over a 2year period using electronic health records (EHRs) from booked consultations in a network of 457 sentinel veterinary premises in the United Kingdom. A semi-automated classification methodology was used to map practitioner defined product codes in 918,333 EHRs from 413,870 dogs and 352,730 EHRs from 200,541 cats, including 289,789 AAPs. AAP as a proportion of total booked consultations was more frequent in dogs (18.8%, 95% confidence interval, CI, 18.2-19.4) than cats (17.5%, 95% CI 16.9-18.1). Prescription of topical antimicrobial agents was more frequent in dogs (7.4%, 95% CI 7.2-7.7) than cats (3.2%, 95% CI 3.1-3.3), whilst prescription of systemic antimicrobial agents was more frequent in cats (14.8%, 95% CI 14.2-15.4) than dogs (12.2%, 95% CI 11.7-12.7). A decreasing temporal pattern was identified for prescription of systemic antimicrobial agents in dogs and cats. Premises which prescribed antimicrobial agents frequently for dogs also prescribed frequently for cats. AAP was most frequent during pruritus consultations in dogs and trauma consultations in cats. Clavulanic acid potentiated amoxicillin was the most frequently prescribed antimicrobial agent in dogs (28.6% of prescriptions, 95% CI 27.4-29.8), whereas cefovecin, a third generation cephalosporin, was the most frequently prescribed antimicrobial agent in cats (36.2%, 95% CI 33.9-38.5). This study demonstrated patterns in AAP over time and for different conditions in a population of companion animals in the United Kingdom. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Free-living Canada geese and antimicrobial resistance.

PubMed

Cole, Dana; Drum, David J V; Stalknecht, David E; White, David G; Lee, Margie D; Ayers, Sherry; Sobsey, Mark; Maurer, John J

2005-06-01

We describe antimicrobial resistance among Escherichia coli isolated from free-living Canada Geese in Georgia and North Carolina (USA). Resistance patterns are compared to those reported by the National Antimicrobial Resistance Monitoring System. Canada Geese may be vectors of antimicrobial resistance and resistance genes in agricultural environments.

Variations in the sales and sales patterns of veterinary antimicrobial agents in 25 European countries.

PubMed

Grave, Kari; Torren-Edo, Jordi; Muller, Arno; Greko, Christina; Moulin, Gerard; Mackay, David

2014-08-01

To describe sales and sales patterns of veterinary antimicrobial agents in 25 European Union (EU)/European Economic Area (EEA) countries for 2011. Data on the sales of veterinary antimicrobial agents from 25 EU member states and EEA countries for 2011 were collected at package level (name, formulation, strength, pack size, number of packages sold) according to a standardized protocol and template and presented in a harmonized manner. These data were calculated to express amounts sold, in metric tonnes, of active ingredient of each package. A population correction unit (PCU) was applied as a proxy for the animal biomass potentially treated with antimicrobial agents. The indicator used to express sales was milligrams of active substance per PCU. Substantial variations in the sales patterns and in the magnitude of sales of veterinary antimicrobial agents, expressed as mg/PCU, between the countries were observed. The proportion of sales, in mg/PCU, of products applicable for treatment of groups or herds of animals (premixes, oral powders and oral solution) varied considerably between the countries. Some countries reported much lower sales of veterinary antimicrobial agents than others, when expressed as mg/PCU. Sales patterns varied between countries, particularly with respect to pharmaceutical forms. Further studies are needed to understand the factors that explain the observed differences. © The Author 2014. 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.

Antimicrobial peptides effectively kill a broad spectrum of Listeria monocytogenes and Staphylococcus aureus strains independently of origin, sub-type, or virulence factor expression.

PubMed

Gottlieb, Caroline Trebbien; Thomsen, Line Elnif; Ingmer, Hanne; Mygind, Per Holse; Kristensen, Hans-Henrik; Gram, Lone

2008-11-26

Host defense peptides (HDPs), or antimicrobial peptides (AMPs), are important components of the innate immune system that bacterial pathogens must overcome to establish an infection and HDPs have been suggested as novel antimicrobial therapeutics in treatment of infectious diseases. Hence it is important to determine the natural variation in susceptibility to HDPs to ensure a successful use in clinical treatment regimes. Strains of two human bacterial pathogens, Listeria monocytogenes and Staphylococcus aureus, were selected to cover a wide range of origin, sub-type, and phenotypic behavior. Strains within each species were equally sensitive to HDPs and oxidative stress representing important components of the innate immune defense system. Four non-human peptides (protamine, plectasin, novicidin, and novispirin G10) were similar in activity profile (MIC value spectrum) to the human beta-defensin 3 (HBD-3). All strains were inhibited by concentrations of hydrogen peroxide between 0.1% - 1.0%. Sub-selections of both species differed in expression of several virulence-related factors and in their ability to survive in human whole blood and kill the nematode virulence model Caenorhabditis elegans. For L. monocytogenes, proliferation in whole blood was paralleled by high invasion in Caco-2 cells and fast killing of C. elegans, however, no such pattern in phenotypic behavior was observed for S. aureus and none of the phenotypic differences were correlated to sensitivity to HDPs. Strains of L. monocytogenes and S. aureus were within each species equally sensitive to a range of HDPs despite variations in subtype, origin, and phenotypic behavior. Our results suggest that therapeutic use of HDPs will not be hampered by occurrence of naturally tolerant strains of the two species investigated in the present study.

Bacterial profile of urinary tract infection and antimicrobial susceptibility pattern among pregnant women attending at Antenatal Clinic in Dil Chora Referral Hospital, Dire Dawa, Eastern Ethiopia

PubMed Central

Derese, Behailu; Kedir, Haji; Teklemariam, Zelalem; Weldegebreal, Fitsum; Balakrishnan, Senthilkumar

2016-01-01

Purpose The aim of this study was to determine the bacterial profile of urinary tract infection (UTI) and antimicrobial susceptibility pattern among pregnant women attending at antenatal clinic in Dil Chora Referral Hospital, Dire Dawa, Eastern Ethiopia. Patients and methods An institutional-based cross-sectional study was conducted from February 18, 2015 to March 25, 2015. Clean-catch midstream urine specimens were collected from 186 pregnant women using sterile containers. Then, culture and antimicrobial susceptibility tests were performed by standard disk diffusion method. Patient information was obtained using pretested structured questionnaire. Data were entered and cleaned using EpiData Version 3 and then exported to Statistical Package for Social Science (Version 16) for further analysis. Results The prevalence of significant bacteriuria was 14%. Gram-negative bacteria were more prevalent (73%). Escherichia coli (34.6%), coagulase-negative staphylococci (19.2%), Pseudomonas aeruginosa (15.4%), and Klebsiella spp. (11.5%) were common bacterial isolates, where most of them were resistant against ampicillin, amoxicillin, tetracycline, trimethoprim–sulfamethoxazole, and chloramphenicol. Multidrug resistance (resistance in ≥2 drugs) was seen in 100% of the isolated bacteria. A majority of the bacterial isolates were sensitive to ciprofloxacin, ceftriaxone, erythromycin, and gentamicin. Conclusion This study found a number of bacterial isolates with very high resistance to the commonly prescribed drugs from pregnant women with and without symptoms of UTI. Therefore, the early routine detection of causative agents of UTI and determining their drug susceptibility pattern are important for pregnant women to avoid complications in mother and fetus. Ciprofloxacin, ceftriaxone, gentamicin, and erythromycin can be used with great care for the empirical treatment of UTI. PMID:26937197

Antimicrobial multidrug resistance and coresistance patterns of Mannheimia haemolytica isolated from bovine respiratory disease cases--a three-year (2009-2011) retrospective analysis.

PubMed

Lubbers, Brian V; Hanzlicek, Gregg A

2013-05-01

Bovine respiratory disease continues to be the most important ailment of feed yard cattle. While the disease is multifactorial in nature, therapy continues to target the primary bacterial pathogens, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni. A survey of records from a single diagnostic laboratory was conducted to evaluate the percentage of M. haemolytica isolates that were resistant to multiple antimicrobials and if coresistance patterns could be detected. All susceptibility test results for M. haemolytica recovered from lung tissues of cattle were eligible for inclusion in the survey. There were no isolates over the course of the analysis that were resistant to all 6 antimicrobials, primarily due to a lack of resistance to ceftiofur. In 2009, just over 5% of isolates were resistant to 5 or more antimicrobials (pan-resistant). In 2011, more than 35% of the M. haemolytica isolates were characterized as pan-resistant. Significant antimicrobial coresistance patterns were only seen with oxytetracycline and tilmicosin; bacterial isolates that were resistant to either oxytetracycline or tilmicosin were more likely to be resistant to at least one other antimicrobial. The mechanisms by which M. haemolytica is developing multidrug resistance warrant investigation if antimicrobial utility in the therapy of bovine respiratory disease is to be preserved.

Chemical composition of the SFE-CO extracts from Cajanus cajan (L.) Huth and their antimicrobial activity in vitro and in vivo.

PubMed

Zu, Yuan-gang; Liu, Xiao-lei; Fu, Yu-jie; Wu, Nan; Kong, Yu; Wink, Michael

2010-12-01

The in vitro and in vivo antimicrobial activities of SFE-CO₂(supercritical fluid extraction) extracts and ethanol extracts from Cajanus cajan (L.) Huth were investigated. The flavonoid compounds orientin, vitexin, isovitexin, pinostrobin and the stilbene cajaninstilbene acid were detected in SFE-CO₂ extracts by HPLC-DAD. In vitro antimicrobial activities of the extracts were evaluated against eight microbial strains (the bacteria Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Proteus vulgaris, Pseudomonas aeruginosa, Escherichia coli; and the fungi Aspergillus niger and Candida albicans). A marked inhibitory effect of the SFE extracts was observed against Staphylococcus epidermidis, Staphylococcus aureus and Bacillus subtilis. The IC(50) of SFE-CO₂ extracts ranged from 0.0557 mg/ml to 0.0689 mg/ml consisting of cancer (MCF-7 (0.0557 mg/ml)) as well as non-cancer (BHK-21 (0.0641 mg/ml), RAW264.7 (0.0689 mg/ml) and Vero (0.0625 mg/ml)) cells. Flow cytometry (FCM) was used to analyze death rate of the most sensitive strain (Staphylococcus aureus) caused by the SFE extracts. Additionally, the whole cell proteins of Staphylococcus aureus were analyzed by SDS-PAGE to detect if there were changes in protein patterns. In vivo antimicrobial activity was studies in mice that had been inoculated with Staphylococcus aureus. The potential mechanism of antimicrobial activity in vivo was studied by histopathology. Copyright © 2010 Elsevier GmbH. All rights reserved.

Longitudinal evaluation of a World Wide Web-based antimicrobial stewardship program: assessing factors associated with approval patterns and trends over time.

PubMed

Venugopal, Vidya; Lehmann, Christoph U; Diener-West, Marie; Agwu, Allison L

2014-02-01

The Johns Hopkins Children's Medical and Surgery Center developed a Web-based Antimicrobial Stewardship Program (ASP) in 2005. The present study aimed to assess longitudinal antimicrobial request and approval patterns for this ASP. We analyzed a total of 16,229 antimicrobial requests for 3,542 patients between June 1, 2005, and June 30, 2009. Antimicrobial approval was the outcome of interest. We assessed gaming by studying trends in automatically approved requests. Nonparametric tests for trend were performed to detect changes in approval patterns. Multiple logistic regression was used to identify factors associated with approval. The vast majority (91.3%) of antimicrobial requests were approved, with an increase of 6.1% over time (P < .01). Renewal requests were more likely than primary requests (adjusted odds ratio [aOR], 1.72; 95% confidence interval [CI], 1.45-2.04) to be approved. Antiviral requests had higher odds of approval than antibiotic requests (aOR, 1.27; 95% CI, 1.04-1.56). Compared with requests by medical services, requests by surgical services had lower odds of approval (aOR, 0.70; 95% CI, 0.59-0.83), whereas pediatric intensive care requests had higher odds of approval (aOR, 1.18; 95% CI, 1.00-1.40). The number of auto-approved requests remained consistent. The Web-based ASP allows management of a large number of antimicrobial requests, without apparent gaming. Observed differences in approval patterns based on patient, requestor, and antimicrobial factors may inform the development of ASPs and evaluation of provider education and training. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Usability application of multiplex polymerase chain reaction in the diagnosis of microorganisms isolated from urine of patients treated in cancer hospital

PubMed Central

Cybulski, Zefiryn; Schmidt, Katarzyna; Grabiec, Alicja; Talaga, Zofia; Bociąg, Piotr; Wojciechowicz, Jacek; Roszak, Andrzej; Kycler, Witold

2013-01-01

Background The objective of this study was: i) to compare the results of urine culture with polymerase chain reaction (PCR) -based detection of microorganisms using two commercially available kits, ii) to assess antimicrobial susceptibility of urine isolates from cancer patients to chosen antimicrobial drugs and, if necessary, to update the recommendation of empirical therapy. Materials and methods. A one-year hospital-based prospective study has been conducted in Greater Poland Cancer Centre and Genetic Medicine Laboratory CBDNA Research Centre in 2011. Urine cultures and urine PCR assay from 72 patients were examined Results Urine cultures and urine PCR assay from 72 patients were examined. Urine samples were positive for 128 strains from which 95 (74%) were identical in both tests. The most frequently isolated bacteria in both culture and PCR assay were coliform organisms and Enterococcus spp. The Gram negative bacilli were most resistant to cotrimoxazol. 77.2% of these bacilli and 100% of E. faecalis and S. agalactiae were sensitive to amoxicillin-clavulanic acid. 4.7% of Gram positive cocci were resistant to nitrofurantoin. Conclusions The PCR method quickly finds the causative agent of urinary tract infection (UTI) and, therefore, it can help with making the choice of the proper antimicrobial therapy at an early stage. It appears to be a viable alternative to the recommendations made in general treatment guidelines, in cases where diversified sensitivity patterns of microorganisms have been found. PMID:24133395

[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.

Antimicrobial resistance and genetic profiling of Escherichia coli from a commercial beef packing plant.

PubMed

Aslam, Mueen; Service, Cara

2006-07-01

The objective of this study was to investigate the extent of antimicrobial resistance and to genetically characterize resistant Escherichia coli recovered from a commercial beef packing plant. E. coli isolates were recovered by a hydrophobic grid membrane filtration method by direct plating on SD-39 medium. A total of 284 isolates comprising 71, 36, 55, 52, and 70 isolates from animal hides, washed carcasses, conveyers, beef trimmings, and ground beef, respectively, were analyzed. The susceptibility of E. coli isolates to 15 antimicrobial agents was evaluated with an automated broth microdilution system, and the genetic characterization of these isolates was performed by the random amplified polymorphic DNA (RAPD) method. Of the 284 E. coli isolates, 56% were sensitive to all 15 antimicrobial agents. Resistance to tetracycline, ampicillin, and streptomycin was observed in 38, 9, and 6% of the isolates, respectively. Resistance to one or more antimicrobial agents was observed in 51% of the E. coli isolates recovered from the hides but in only 25% of the E. coli from the washed carcasses. Resistance to one or more antimicrobial agents was observed in 49, 50, and 37% of the isolates recovered from conveyers, beef trimmings, and ground beef, respectively. The RAPD pattern data showed that the majority of resistant E. coli isolates were genetically diverse. Only a few RAPD types of resistant strains were shared among various sample sources. The results of this study suggest that antimicrobial-resistant E. coli isolates were prevalent during all stages of commercial beef processing and that considerably higher numbers of resistant E. coli were present on conveyers, beef trimmings, and ground beef than on dressed carcasses. This stresses the need for improving hygienic conditions during all stages of commercial beef processing and meatpacking to avoid the risks of transfer of antimicrobial-resistant bacteria to humans.

In Vitro Antimicrobial Susceptibility Patterns of Blastocystis

PubMed Central

Bush, Stephen; Ellis, John; Harkness, John; Stark, Damien

2015-01-01

Blastocystis is the most common human enteric protist with controversial clinical significance. Metronidazole is considered a first-line treatment for Blastocystis infection; however, there has been increasing evidence for the lack of efficacy of this treatment. Treatment failure has been reported in several clinical cases, and recent in vitro studies have suggested the occurrence of metronidazole-resistant strains. In this study, we tested 12 Blastocystis isolates from 4 common Blastocystis subtypes (ST1, ST3, ST4, and ST8) against 12 commonly used antimicrobials (metronidazole, paromomycin, ornidazole, albendazole, ivermectin, trimethoprim-sulfamethoxazole [TMP-SMX], furazolidone, nitazoxanide, secnidazole, fluconazole, nystatin, and itraconazole) at 10 different concentrations in vitro. It was found that each subtype showed little sensitivity to the commonly used metronidazole, paromomycin, and triple therapy (furazolidone, nitazoxanide, and secnidazole). This study highlights the efficacy of other potential drug treatments, including trimethoprim-sulfamethoxazole and ivermectin, and suggests that current treatment regimens be revised. PMID:25987633

Antimicrobial resistence of Shigella species isolated during 2004 and 2005 from selected sites in Zimbabwe.

PubMed

Ndlovu, N; Tarupiwa, A; Mudzori, J T

2006-01-01

To determine the predominant serotype and antibiotic sensitivity pattern of Shigella isolates during 2004 and 2005 in Zimbabwe. Cross sectional study. National Microbiology Reference Laboratory (NMRL), Harare, Zimbabwe. 259 clinical isolates of Shigella species isolated during 2004 and 2005 in Zimbabwe were studied. These samples had been referred to the NMRL for further testing. Serotype and antibiotic sensitivity pattern of Shigella species. Of the 259 clinical isolates of Shigella tested the following species were serotyped; 141 (54.4%) were S. flexneri; 70 (27%) S. sonnei; 38 (14.7%) S. dysenteriae and 10 (3.9%) S. boydii. About 4% of all Shigella isolates tested showed full sensitivity to commonly used antibiotics, 20.8% were resistant to one antibiotic only while 75.3% were resistant to at least two antibiotics. The most common resistance among Shigella species was to cotrimoxazole (89%), tetracycline (73%), ampicillin (49%) and chloramphenicol (41%). High susceptibility among Shigella species was observed to nalidixic acid (86%), ciprofloxacin (99%) and ceftazidine (99%). There was a low drug resistance of Shigella species to nalidixic acid, a drug of choice in Zimbabwe, except among Shigella dysenteriae type 1 strains. Continuous monitoring of the susceptibility patterns of Shigella species is important in order to detect the emergence of drug resistance and to update guidelines for antibiotic treatment in shigellosis.

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.

A comparison of non-typhoidal Salmonella from humans and food animals using pulsed-field gel electrophoresis and antimicrobial susceptibility patterns

USDA-ARS?s Scientific Manuscript database

Salmonellosis is one of the most important foodborne diseases affecting humans. To characterize the relationship between Salmonella causing human infections and their food animal reservoirs, we compared pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility patterns of non-typhoida...

Patterns of antimicrobial use for respiratory tract infections in older residents of long-term care facilities

USDA-ARS?s Scientific Manuscript database

OBJECTIVE: To describe patterns of antimicrobial use for respiratory tract infections (RTIs) among elderly residents of long-term care facilities (LTCFs). DESIGN: Data from a prospective, randomized, controlled study conducted from April 1998 through August 2001 to investigate the effect of vitamin ...

Some virulence characteristics of uropathogenic Escherichia coli in different patient groups.

PubMed

Naveen, Rebecca; Mathai, Elizabeth

2005-08-01

Uropathogenic Escherichia coli have virulence properties, that are absent in non pathogenic E. coli. The distribution of these markers can vary according to patient populations. Hence, a study was undertaken to describe the presence of virulence factors like Pfimbriae, type 1 fimbriae and haemolysin in E.coli causing urinary infections in three groups of patients. Antibiogram was also recorded to determine differences, if any, between the groups. E. coli isolated from three groups of subjects, in counts of >10(5) CFU/ml and in pure growth were tested for mannose resistant haemagglutination (MRHA) to indicate P fimbriae and mannose sensitive haemagglutination (MSHA) to indicate type 1 fimbriae. Haemolysin production and antimicrobial susceptibility patterns were also recorded. Significantly more isolates from antenatal and postnatal women possessed P fimbriae compared to groups with urologic abnormalities (P=0.05). Haemolysin production was also significantly higher (P<0.001) in this group. Greater proportions of isolates from pregnant women were susceptible to commonly used antimicrobials. However, resistance to third generation cephalosporins was present even in these isolates from community infections. In patients with urological abnormality, E. coli with lower virulence can cause infections. Isolates from these patients exhibited greater drug resistance. In pregnant women and in community acquired infections, simple antimicrobial drugs like nitrofurantoin might still be useful. However, urgent and stringent policies for antimicrobial use and infection control in hospitals are required in India.

An association of genotypes and antimicrobial resistance patterns among Salmonella isolates from pigs and humans in Taiwan.

PubMed

Kuo, Hung-Chih; Lauderdale, Tsai-Ling; Lo, Dan-Yuan; Chen, Chiou-Lin; Chen, Pei-Chen; Liang, Shiu-Yun; Kuo, Jung-Che; Liao, Ying-Shu; Liao, Chun-Hsing; Tsao, Chi-Sen; Chiou, Chien-Shun

2014-01-01

We collected 110 Salmonella enterica isolates from sick pigs and determined their serotypes, genotypes using pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility to 12 antimicrobials and compared the data with a collection of 18,280 isolates obtained from humans. The pig isolates fell into 12 common serovars for human salmonellosis in Taiwan; S. Typhimurium, S. Choleraesuis, S. Derby, S. Livingstone, and S. Schwarzengrund were the 5 most common serovars and accounted for a total of 84% of the collection. Of the 110 isolates, 106 (96%) were multidrug resistant (MDR) and 48 (44%) had PFGE patterns found in human isolates. S. Typhimurium, S. Choleraesuis, and S. Schwarzengrund were among the most highly resistant serovars. The majority of the 3 serovars were resistant to 8-11 of the tested antimicrobials. The isolates from pigs and humans sharing a common PFGE pattern displayed identical or very similar resistance patterns and Salmonella strains that caused severe infection in pigs were also capable of causing infections in humans. The results indicate that pigs are one of the major reservoirs to human salmonellosis in Taiwan. Almost all of the pig isolates were MDR, which highlights the necessity of strictly regulating the use of antimicrobials in the agriculture sector in Taiwan.

Short communication: Antimicrobial susceptibility profiling and genotyping of Staphylococcus aureus isolates from bovine mastitis in Poland.

PubMed

Jagielski, T; Puacz, E; Lisowski, A; Siedlecki, P; Dudziak, W; Międzobrodzki, J; Krukowski, H

2014-10-01

Staphylococcus aureus is the predominant causative agent of bovine mastitis, a disease that remains a major economic burden for the dairy industry worldwide. In this study, the antimicrobial resistance patterns and the genetic composition of 80 S. aureus mastitis isolates collected from 14 dairy farms in Eastern Poland were determined. Of the 10 antimicrobial agents evaluated, only testing for penicillin G produced drug resistance. As 41% of the S. aureus isolates were penicillin resistant, this drug along with other β-lactamase-sensitive β-lactams, should rather not be considered for the treatment of bovine mastitis caused by S. aureus. Upon genotyping, with a triplex PCR method, a total of 11 distinct PCR types were produced. The population structure of S. aureus isolates was highly clonal, with 1 predominant genotype circulating on each farm. The observed similarities in the genotype composition of S. aureus populations from geographically distant farms underscore the significance of interfarm transmission of S. aureus in Poland. This, in turn, argues for the establishment of a nationwide surveillance program for bovine mastitis due to this pathogen. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Antimicrobial susceptibility patterns of Ureaplasma species and Mycoplasma hominis in pregnant women.

PubMed

Redelinghuys, Mathys J; Ehlers, Marthie M; Dreyer, Andries W; Lombaard, Hennie A; Kock, Marleen M

2014-03-28

Genital mycoplasmas colonise up to 80% of sexually mature women and may invade the amniotic cavity during pregnancy and cause complications. Tetracyclines and fluoroquinolones are contraindicated in pregnancy and erythromycin is often used to treat patients. However, increasing resistance to common antimicrobial agents is widely reported. The purpose of this study was to investigate antimicrobial susceptibility patterns of genital mycoplasmas in pregnant women. Self-collected vaginal swabs were obtained from 96 pregnant women attending an antenatal clinic in Gauteng, South Africa. Specimens were screened with the Mycofast Revolution assay for the presence of Ureaplasma species and Mycoplasma hominis. The antimicrobial susceptibility to levofloxacin, moxifloxacin, erythromycin, clindamycin and tetracycline were determined at various breakpoints. A multiplex polymerase chain reaction assay was used to speciate Ureaplasma positive specimens as either U. parvum or U. urealyticum. Seventy-six percent (73/96) of specimens contained Ureaplasma spp., while 39.7% (29/73) of Ureaplasma positive specimens were also positive for M. hominis. Susceptibilities of Ureaplasma spp. to levofloxacin and moxifloxacin were 59% (26/44) and 98% (43/44) respectively. Mixed isolates (Ureaplasma species and M. hominis) were highly resistant to erythromycin and tetracycline (both 97% resistance). Resistance of Ureaplasma spp. to erythromycin was 80% (35/44) and tetracycline resistance was detected in 73% (32/44) of Ureaplasma spp. Speciation indicated that U. parvum was the predominant Ureaplasma spp. conferring antimicrobial resistance. Treatment options for genital mycoplasma infections are becoming limited. More elaborative studies are needed to elucidate the diverse antimicrobial susceptibility patterns found in this study when compared to similar studies. To prevent complications in pregnant women, the foetus and the neonate, routine screening for the presence of genital mycoplasmas is recommended. In addition, it is recommended that antimicrobial susceptibility patterns are determined.

Antimicrobial susceptibility patterns of Ureaplasma species and Mycoplasma hominis in pregnant women

PubMed Central

2014-01-01

Background Genital mycoplasmas colonise up to 80% of sexually mature women and may invade the amniotic cavity during pregnancy and cause complications. Tetracyclines and fluoroquinolones are contraindicated in pregnancy and erythromycin is often used to treat patients. However, increasing resistance to common antimicrobial agents is widely reported. The purpose of this study was to investigate antimicrobial susceptibility patterns of genital mycoplasmas in pregnant women. Methods Self-collected vaginal swabs were obtained from 96 pregnant women attending an antenatal clinic in Gauteng, South Africa. Specimens were screened with the Mycofast Revolution assay for the presence of Ureaplasma species and Mycoplasma hominis. The antimicrobial susceptibility to levofloxacin, moxifloxacin, erythromycin, clindamycin and tetracycline were determined at various breakpoints. A multiplex polymerase chain reaction assay was used to speciate Ureaplasma positive specimens as either U. parvum or U. urealyticum. Results Seventy-six percent (73/96) of specimens contained Ureaplasma spp., while 39.7% (29/73) of Ureaplasma positive specimens were also positive for M. hominis. Susceptibilities of Ureaplasma spp. to levofloxacin and moxifloxacin were 59% (26/44) and 98% (43/44) respectively. Mixed isolates (Ureaplasma species and M. hominis) were highly resistant to erythromycin and tetracycline (both 97% resistance). Resistance of Ureaplasma spp. to erythromycin was 80% (35/44) and tetracycline resistance was detected in 73% (32/44) of Ureaplasma spp. Speciation indicated that U. parvum was the predominant Ureaplasma spp. conferring antimicrobial resistance. Conclusions Treatment options for genital mycoplasma infections are becoming limited. More elaborative studies are needed to elucidate the diverse antimicrobial susceptibility patterns found in this study when compared to similar studies. To prevent complications in pregnant women, the foetus and the neonate, routine screening for the presence of genital mycoplasmas is recommended. In addition, it is recommended that antimicrobial susceptibility patterns are determined. PMID:24679107

Occurrence of antimicrobial resistance in bacteria from diagnostic samples from dogs.

PubMed

Pedersen, Karl; Pedersen, Kristina; Jensen, Helene; Finster, Kai; Jensen, Vibeke F; Heuer, Ole E

2007-10-01

To study the occurrence of antimicrobial resistance among common bacterial pathogens from dogs and relate resistance patterns to data on consumption of antimicrobials. The antimicrobial susceptibility patterns of 201 Staphylococcus intermedius, 37 Streptococcus canis, 39 Pseudomonas aeruginosa, 25 Pasteurella multocida, 29 Proteus spp. and 449 Escherichia coli isolates from clinical submissions from dogs were determined by a broth-dilution method for determination of minimal inhibitory concentration. Data for consumption of antimicrobials were retrieved from VetStat, a national database for reporting antimicrobial prescriptions. The majority of the antimicrobials prescribed for dogs were broad-spectrum compounds, and extended-spectrum penicillins, cephalosporins and sulphonamides + trimethoprim together accounted for 81% of the total amount used for companion animals. Resistance to cephalosporins and amoxicillin with clavulanic acid was very low for all bacterial species examined, except for P. aeruginosa, and resistance to sulphonamides and trimethoprim was low for most species. Among the S. intermedius isolates, 60.2% were resistant to penicillin, 30.2% to fusidic acid and 27.9% to macrolides. Among E. coli isolates, the highest level of resistance was recorded for ampicillin, sulphonamides, trimethoprim, tetracyclines and streptomycin. Certain differences in resistance patterns between isolates from different sites or organs were noticed for E. coli, S. intermedius and Proteus isolates. This investigation provided data on occurrence of antimicrobial resistance in important pathogenic bacteria from dogs, which may be useful for the small animal practitioner. Resistance was low to the compounds that were most often used, but unfortunately, these compounds were broad-spectrum. Data on resistance and usage may form a background for the establishment of a set of recommendations for prudent use of antimicrobials for companion animals.

In Vitro Sensitivity and Resistance of 46 Leptospira Strains Isolated from Rats in the Philippines to 14 Antimicrobial Agents▿ †

PubMed Central

Chakraborty, Antara; Miyahara, Satoshi; Villanueva, Sharon Y. A. M.; Gloriani, Nina G.; Yoshida, Shin-ichi

2010-01-01

The in vitro susceptibilities of 46 Leptospira isolates from rats to 14 antimicrobial agents were tested. All of the strains were found to be sensitive to ampicillin, cefotaxime, ciprofloxacin, norfloxacin, doxycycline, erythromycin, and streptomycin. In contrast, the tested isolates showed resistance to amphotericin B, 5-fluorouracil, fosfomycin, trimethoprim, sulfamethoxazole, neomycin, and vancomycin. These findings will help in selecting effective and ineffective antimicrobials for treatment of leptospirosis and for the development of new selective media, respectively. PMID:20855741

Antimicrobial susceptibility of corynebacteria isolated from ewe's mastitis.

PubMed

Fernández, E P; Vela, A I; Las Heras, A; Domínguez, L; Fernández-Garayzábal, J F; Moreno, M A

2001-12-01

The antimicrobial susceptibility of 50 coryneform isolates from subclinical mastitis in sheep was evaluated. Arcanobacterium pyogenes (five isolates) had a susceptibility pattern distinct from the Corynebacterium species tested. The Corynebacterium isolates could be divided in two groups according to the MIC values for ciprofloxacin. Their antimicrobial susceptibility was usually unpredictable and consequently antimicrobial susceptibility tests are necessary for clinical and epidemiological purposes.

Phenotypical and Genotypical Antimicrobial Resistance of Coagulase-negative staphylococci Isolated from Cow Mastitis.

PubMed

Klimiene, I; Virgailis, M; Pavilonis, A; Siugzdiniene, R; Mockeliunas, R; Ruzauskas, M

2016-09-01

The objectives of this study were to determine the prevalence and antimicrobial resistance of coagulase-negative staphylococci (CNS) isolated from dairy cows with subclinical mastitis. Antimicrobial resistance in staphylococci were evaluated by breakpoint values specific to the species (EU-CAST). The presence of resistance-encoding genes was detected by multiplex PCR. A total of 191 CNS isolates were obtained. The CNS isolates were typically resistant to penicillin (67.4%), tetracyc-line (18.9%), and erythromycin (13.7%). CNS isolates (78.0%) were resistant to at least one antimicrobial compound, and 22.0% were multiresistant. The multiresistant isolates were predominantly Staphylococcus chromogenes (28.6%), Staphylococcus warneri (19%) and Staphylococcus haemolyticus (14.3%). According to MIC pattern data, multiresistant isolates showed the highest resistance (p<0.05) rates to penicillin (85.7%), tetracycline (66.7%), and erythromycin (48.2%), but all of them were sensitive to daptomycin, oxacillin, qiunupristin/dalfopristin, and vancomycin. S. chromogenes (9.5%), S. haemolyticus (4.8%), and S. capitis ss capitis (2.4%) strains were resistant to methicillin; their resistance to oxacillin and penicillin was more than 8 mg/l. A high rate of resistance to penicillin was linked to a blaZ gene found in 66.6% of the isolated multiresistant CNS strains. Resistance to tetracycline via the tetK (38.1%) gene and penicillin via the mecA (23.8%) gene were detected less frequently. Gene msrAB was responsible for macrolides and lincosamides resistance and detected in 28.6% of the CNS isolates. Antimicrobial resistance genes were identified more frequently in S. epidermidis, S. chromogenes, and S. warneri.

Antimicrobial activity of spices.

PubMed

Arora, D S; Kaur, J

1999-08-01

Spices have been shown to possess medicinal value, in particular, antimicrobial activity. This study compares the sensitivity of some human pathogenic bacteria and yeasts to various spice extracts and commonly employed chemotherapeutic substances. Of the different spices tested only garlic and clove were found to possess antimicrobial activity. The bactericidal effect of garlic extract was apparent within 1 h of incubation and 93% killing of Staphylococcus epidermidis and Salmonella typhi was achieved within 3 h. Yeasts were totally killed in 1 h by garlic extract but in 5 h with clove. Some bacteria showing resistance to certain antibiotics were sensitive to extracts of both garlic and clove. Greater anti-candidal activity was shown by garlic than by nystatin. Spices might have a great potential to be used as antimicrobial agents.

Spectrum of systemic bacterial infections during febrile neutropenia in pediatric oncology patients in tertiary care pediatric center.

PubMed

Siddaiahgari, Sirisharani; Manikyam, A; Kumar, K Anand; Rauthan, A; Ayyar, R

2014-01-01

Outcome of pediatric cancers has significantly improved with modern chemotherapy and good supportive care. However, febrile neutropenia remains one of the important limiting factors in these patients especially with the emergence of resistant organisms. Choosing appropriate antimicrobials is possible only if we understand the local microbial spectrum and their sensitivity pattern. To study the likely etiologic agents and their antibiotic sensitivity pattern among systemic infections in children with cancer. This is a prospective study. The study was conducted at a tertiary care center for pediatrics, in which culture samples representing blood stream infections and others like urinary tract infections sent from the Oncology services of the Hospital during the year of 2013 were analyzed. The microbiological profile and antibiotic sensitivity pattern of these isolates were studied. There were 89 isolates that represented blood and urinary tract infections in neutropenic patients with cancer.Out of 89 positive cultures 76 were gram negative isolates. The most common gram negative bacterial isolates were Escherichia coli 33 (37%), followed by Pseudomonas 21 (23.5%). Acinetobacter grew in 2 patients (2.2%). Extended spectrum beta-lactamases (ESBL's), carbepenem resistant and pan-resistant organisms seen in 28 (31.4%), 5 (5.6%) and 2 cases (2.3%) respectively. Over all Gram-positive organisms were 13/89 (12.3%). Staphylococcus was the most common Gram-positive organism and methicillin resistant Staphylococcus aureus seen in 5 each. Gram-negative organism is a common isolate in cancer children with febrile neutropenia, which is resistant to first-line antibiotic cefepime. Meropenem is most sensitive antibiotic and ESBL's are sensitive to piperacillin-tazobactam.

Microbiological diagnosis and antimicrobial sensitivity profiles in diseased free-living raptors.

PubMed

Vidal, Anna; Baldomà, Laia; Molina-López, Rafael A; Martin, Marga; Darwich, Laila

2017-08-01

Free-living raptors (birds of prey) can act as reservoirs of potentially zoonotic agents, but they also can be affected by microorganisms as target hosts. In this retrospective study, microbiological results (n = 663) and antibiotic sensitivity profiles (n = 108) of bacterial isolates were analysed from diseased free-living raptors. Sixty-nine percent of cases (n = 457) yielded bacteria: 58% were in pure culture and 42% were of different species. Remarkably, samples from necropsies (47%) had higher percentage of pure isolations than those obtained from clinical (31%) samples (P < 0.001). Among bacterial isolates, Escherichia coli was the most common agent (35%), principally recovered from necropsied birds with clinical signs of septicaemia or respiratory disorders. Pseudomonas aeruginosa (7%) was isolated from birds with systemic infection and from oral lesions, especially in nocturnal raptors (P < 0.001). Staphylococcus spp. (5%), mainly Staphylococcus aureus, was found to be the most prevalent cause of pododermatitis (35%) and Staphylococcus hyicus was isolated from conjunctivitis (18.2%). Interestingly, 8% of samples with lesions compatible with avian tuberculosis were positive to the Mycobacterium avium complex. The most frequent fungi associated with pneumonic lesions and ingluvitis were Aspergillus spp. and Candida spp., respectively. More than 50% of the 108 isolates (34 different bacterial spp.) demonstrated resistance to clindamycin, ampicillin, tetracycline, cefuroxime, enrofloxacin and trimethoprim/sulphamethoxazole. Among the E. coli strains, 71% (27/38) presented a multidrug-resistance pattern to >3 antimicrobials. Detection in wildlife of antimicrobial-resistant pathogens that might be significant at the animal-human-ecosystem interface is of great relevance under the 'One Health' approach.

Nanostructures for delivery of natural antimicrobials in food.

PubMed

Lopes, Nathalie Almeida; Brandelli, Adriano

2017-04-10

Natural antimicrobial compounds are a topic of utmost interest in food science due to the increased demand for safe and high-quality foods with minimal processing. The use of nanostructures is an interesting alternative to protect and delivery antimicrobials in food, also providing controlled release of natural compounds such as bacteriocins and antimicrobial proteins, and also for delivery of plant derived antimicrobials. A diversity of nanostructures are capable of trapping natural antimicrobials maintaining the stability of substances that are frequently sensitive to food processing and storage conditions. This article provides an overview on natural antimicrobials incorporated in nanostructures, showing an effective antimicrobial activity on a diversity of food spoilage and pathogenic microorganisms.

Dana Cole, Georgia Division of Public Health, Notifiable Disease Section, Department of Human Resources, 2 Peachtree Free-living Canada Geese and Antimicrobial Resistance

PubMed Central

Cole, Dana; Drum, David J.V.; Stallknecht, David E.; White, David G.; Lee, Margie D.; Ayers, Sherry; Sobsey, Mark; Maurer, John J.

2005-01-01

We describe antimicrobial resistance among Escherichia coli isolated from free-living Canada Geese in Georgia and North Carolina (USA). Resistance patterns are compared to those reported by the National Antimicrobial Resistance Monitoring System. Canada Geese may be vectors of antimicrobial resistance and resistance genes in agricultural environments. PMID:15963291

Characterization of Salmonella enterica serovar Agona slaughter isolates from the animal arm of the National Antimicrobial Resistance Monitoring System-Enteric Bacteria (NARMS): 1997 through 2003.

PubMed

Douris, Aphrodite; Fedorka-Cray, Paula J; Jackson, Charlene R

2008-03-01

A total of 499 Salmonella enterica serovar Agona isolates from cattle, swine, chicken, and turkey samples were assayed for antimicrobial susceptibility and subtyped using pulsed-field gel electrophoresis (PFGE). Salmonella Agona isolates exhibited increased resistance to amoxicillin/clavulanic acid, ampicillin, cefoxitin, ceftiofur, cephalothin, and chloramphenicol, and a single isolate was resistant to ceftriaxone. Multiple drug resistance (MDR; resistance >or= 2 antimicrobials) was exhibited in 57% (n=282/499) of the Salmonella Agona isolates and 22% (n=111/499) of these Salmonella Agona isolates were resistant to five or more antimicrobials. PFGE patterns of 482 Salmonella Agona slaughter samples resulted in 165 unique patterns. Cluster analysis indicated that isolates indistinguishable by PFGE appeared to group according to antimicrobial resistance profiles. These data suggest that Salmonella Agona is increasing in prevalence in U.S. cattle presented for slaughter and should be further monitored.

Identifying priorities to improve paediatric in-hospital antimicrobial use by cross-sectional evaluation of prevalence and appropriateness of prescription.

PubMed

Goycochea-Valdivia, Walter Alfredo; Moreno-Ramos, Francisco; Paño-Pardo, José Ramón; Aracil-Santos, Francisco Javier; Baquero-Artigao, Fernando; Del Rosal-Rabes, Teresa; Mellado-Peña, María José; Escosa-García, Luis

2017-11-01

Information about paediatric in-hospital antimicrobial usage and prescribing patterns to guide improvement strategies is scant. We aim to use an evaluation of the prevalence and appropriateness of antimicrobial prescription to identify antimicrobial stewardship priorities in children. A cross-sectional point study was performed on hospitalised paediatric patients in a Spanish tertiary hospital, assessing the prevalence of antimicrobial prescription (PAP) and appropriateness of antimicrobial prescription (AAP). AAP was defined as a correct indication plus an appropriate prescribing pattern (dose, spectrum and interval). Evaluation was performed using established antimicrobial guidelines. Other factors that may have a bearing on antimicrobial prescription were also analysed. A total of 171 patients were included. PAP was 49.7% (85/171) and AAP was 60.9% (91/161). The most common indications for antimicrobial use were antimicrobial prophylaxis (28.3%, 32/113) and pneumonia (8.2%, 8/113). Overall, 161 antimicrobials were prescribed (1.9 antimicrobials per patient): 55.3% (89/161) were empiric, 16.1% (26/161) were targeted and 28.6% (46/161) were prophylactic. Amoxicillin/clavulanate (8.2%, 14/171) and sulfamethoxazole/trimethoprim (8.2%, 14/171) were the most prescribed antimicrobials. The prescription of antifungals (11.7%, 20/171) and antivirals (1.8%, 3/171) was analysed. Major causes of inappropriate antibiotic use were prolonged prescriptions (21.7%, 35/161) and use of agents with an excessively broad coverage spectrum (21.1%, 34/161). PAP and AAP varied between wards and antimicrobials. Measurement of PAP and AAP offers valuable information for detecting priorities in hospital settings and monitoring antimicrobial usage prior to the development of antimicrobial stewardship programmes. In our setting, the main areas for improvement are duration of therapy and proper use of broad-spectrum antimicrobials. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Patterns of Antimicrobial Resistance Observed in Escherichia coli Isolates Obtained from Domestic- and Wild-Animal Fecal Samples, Human Septage, and Surface Water

PubMed Central

Sayah, Raida S.; Kaneene, John B.; Johnson, Yvette; Miller, RoseAnn

2005-01-01

A repeated cross-sectional study was conducted to determine the patterns of antimicrobial resistance in 1,286 Escherichia coli strains isolated from human septage, wildlife, domestic animals, farm environments, and surface water in the Red Cedar watershed in Michigan. Isolation and identification of E. coli were done by using enrichment media, selective media, and biochemical tests. Antimicrobial susceptibility testing by the disk diffusion method was conducted for neomycin, gentamicin, streptomycin, chloramphenicol, ofloxacin, trimethoprim-sulfamethoxazole, tetracycline, ampicillin, nalidixic acid, nitrofurantoin, cephalothin, and sulfisoxazole. Resistance to at least one antimicrobial agent was demonstrated in isolates from livestock, companion animals, human septage, wildlife, and surface water. In general, E. coli isolates from domestic species showed resistance to the largest number of antimicrobial agents compared to isolates from human septage, wildlife, and surface water. The agents to which resistance was demonstrated most frequently were tetracycline, cephalothin, sulfisoxazole, and streptomycin. There were similarities in the patterns of resistance in fecal samples and farm environment samples by animal, and the levels of cephalothin-resistant isolates were higher in farm environment samples than in fecal samples. Multidrug resistance was seen in a variety of sources, and the highest levels of multidrug-resistant E. coli were observed for swine fecal samples. The fact that water sample isolates were resistant only to cephalothin may suggest that the resistance patterns for farm environment samples may be more representative of the risk of contamination of surface waters with antimicrobial agent-resistant bacteria. PMID:15746342

Distribution, Detection of Enterotoxigenic Strains and Antimicrobial Drug Susceptibility Patterns of Bacteroides Fragilis Group in Diarrheic and Non-Diarrheic Feces from Brazilian Infants

PubMed Central

Ferreira, Débora Paula; Silva, Vânia Lúcia; Guimarães, Danielle Aparecida; Coelho, Cíntia Marques; Zauli, Danielle Alves Gomes; Farias, Luiz Macêdo; Carvalho, Maria Auxiliadora Roque; Diniz, Claudio Galuppo

2010-01-01

Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG) are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110) and non-diarrheic (n=65) fecal samples from children aged 0–5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic), and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children. PMID:24031535

Surveillance of antimicrobial susceptibility patterns among Shigella species isolated in China during the 7-year period of 2005-2011.

PubMed

Yang, Haifei; Chen, Guosheng; Zhu, Yulin; Liu, Yanyan; Cheng, Jun; Hu, Lifen; Ye, Ying; Li, Jiabin

2013-03-01

Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with antibiotics is recommended for shigellosis, but the options are limited due to globally emerging resistance. This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of Shigella in China. We studied the antimicrobial resistance profiles of 308 Shigella spp. strains (260 S. flexneri, 40 S. sonnei, 5 S. boydii, and 3 S. dysenteriae) isolated from fecal samples of patients (age, from 3 months to 92 yr) presenting with diarrhea in different districts of Anhui, China. The antimicrobial resistance of strains was determined by the agar dilution method according to the CSLI guidelines. The most common serogroup in the Shigella isolates was S. flexneri (n=260, 84.4%), followed by S. sonnei (n=40, 13.0%). The highest resistance rate was found for nalidixic acid (96.4%), followed by ampicillin (93.2%), tetracycline (90.9%), and trimethoprim/sulfamethoxazole (80.8%). Among the isolates tested, 280 (91.0%) were multidrug resistant (resistant to ≥2 agents). The most common resistance pattern was the combination of ampicillin, tetracycline, and trimethoprim/sulfamethoxazole (70.8%). Resistance to ampicillin and tetracycline were more common among S. flexneri than among S. sonnei isolates. S. flexneri is predominant in Anhui, China, and its higher antimicrobial resistance rate compared with that of S. sonnei is a cause for concern. Continuous monitoring of resistance patterns is necessary to control the spread of resistance in Shigella. The recommendations for antimicrobial treatment must be updated regularly based on surveillance results.

Common phenotypic and genotypic antimicrobial resistance patterns found in a case study of multiresistant E. coli from cohabitant pets, humans, and household surfaces.

PubMed

Martins, Liliana Raquel Leite; Pina, Susana Maria Rocha; Simões, Romeo Luís Rocha; de Matos, Augusto José Ferreira; Rodrigues, Pedro; da Costa, Paulo Martins Rodrigues

2013-01-01

The objective of the study described in this article was to characterize the antimicrobial resistance profiles among E. coli strains isolated from cohabitant pets and humans, evaluating the concurrent colonization of pets, owners, and home surfaces by bacteria carrying the same antimicrobial-resistant genes. The authors also intended to assess whether household surfaces and objects could contribute to the within-household antimicrobial-resistant gene diffusion between human and animal cohabitants. A total of 124 E. coli strains were isolated displaying 24 different phenotypic patterns with a remarkable percentage of multiresistant ones. The same resistance patterns were isolated from the dog's urine, mouth, the laundry floor, the refrigerator door, and the dog's food bowl. Some other multiresistant phenotypes, as long as resistant genes, were found repeatedly in different inhabitants and surfaces of the house. Direct, close contact between all the cohabitants and the touch of contaminated household surfaces and objects could be an explanation for these observations.

A novel direct contact method for the assessment of the antimicrobial activity of dental cements.

PubMed

Costa, E M; Silva, S; Madureira, A R; Cardelle-Cobas, A; Tavaria, F K; Pintado, M M

2013-06-01

Dental cements are a crucial part of the odontological treatment, however, due to the hazardous nature and reduced biological efficiency of some of the used materials, newer and safer alternatives are needed, particularly so those possessing higher antimicrobial activity than their traditional counterparts. The evaluation of the antimicrobial properties of solid and semi-solid antimicrobials, such as dental cements and gels, is challenging, particularly due to the low sensitivity of the current methods. Thus, the main aim of this study was the evaluation of the antimicrobial activity of a novel chitosan containing dental cement while simultaneous assessing/validating a new, more efficient, method for the evaluation of the antimicrobial activity of solid and gel like materials. The results obtained showed that the proposed method exhibited a higher sensitivity than the standard 96 well microtiter assay and allowed the determination of bactericidal activity. Additionally, it is interesting to note that the chitosan containing cement, which presented higher antimicrobial activity than the traditional zinc oxide/eugenol mix, was capable of inducing a viable count reduction above 5 log of CFU for all of the studied microorganisms. Copyright © 2013 Elsevier B.V. All rights reserved.

Insights into the Enhanced in vivo Fitness of Neisseria gonorrhoeae Driven by a Fluoroquinolone Resistance-Conferring Mutant DNA Gyrase

DTIC Science & Technology

2015-02-05

enhancement in fitness relative to its parent strain was also more resistant to human and bacterial antimicrobial peptides , including the cathelicidins...32 Deep sequencing data analysis.............................................................................. 33 Antimicrobial peptide ...Sensitivity to cationic antimicrobial peptides ....................................................... 57 In vivo competitive infection in wild-type and

[Antimicrobial sensitivity of the environmental microbiota in the intensive care units of a peruvian hospital].

PubMed

Díaz-Tello, José; Rojas-Jaimes, Jesús; Ibarra-Trujillo, Jimmy; Tárraga-Gonzales, Delza

2017-01-01

The objective was to detect Gram-negative bacilli and Gram-positive cocci isolated from the environmental microbiota of the Intensive Care Unit (ICU) departments of Neonatology, Pediatrics, and Transplants (kidney, liver, and general) in a Lima hospital and determine their antimicrobial sensitivity. Eighty samples were obtained from inanimate surfaces using a wet swab. A total of 61 bacterial strains were identified, including Staphylococcus epidermis (46.0%), Alcaligenes sp. (21.3%), Pseudomonas aeruginosa (16.4%), Acinetobacter sp. (13.1%), Staphylococcus aureus (1.6%), and Staphylococcus haemolyticus (1.6%). Acinetobacter sp. and P. aeruginosa showed a heightened sensitivity to the antibiotics assessed, while Alcaligenes sp. and S. epidermidis presented the highest antimicrobial resistance. It is recommended that sustained asepsis and monitoring methods be used in ICUs.

Investigation of antimicrobial use pattern in the intensive treatment unit of a teaching hospital in western Nepal.

PubMed

Shankar, P Ravi; Partha, Praveen; Shenoy, Nagesh; Brahmadathan, K N

2003-11-01

Inappropriate use of antimicrobials is of special importance in the intensive treatment unit because of the large number of drugs prescribed, the chance for drug errors, and the likelihood of development of drug resistance. A total of 297 records of patients admitted to the intensive treatment unit of the Manipal teaching hospital, a tertiary care hospital in Pokhara, western Nepal, were studied to determine the prescribing frequency and rationality of use of antimicrobials. Patient outcome, duration of stay in the intensive treatment unit, and the age and sex distribution of the patients were also studied. Mean+/-SD drugs per patient was 3.4+/-1.8. About half (50.2%) of the patients received an antimicrobial; 84.6% of the antimicrobials were used without obtaining bacteriologic evidence of infection. The commonest organisms isolated on culture were Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus pneumoniae, and Staphylococcus aureus. A total of 28.9% of the antimicrobials were prescribed for lower respiratory tract infections on the basis of the putative site of infection; 61.9% of the antimicrobials were prescribed by the parenteral route and mainly the older generation of antimicrobials were used. In 39 of the 149 patients prescribed an antimicrobial, the use was irrational. Prescriber education to improve prescribing patterns and regular auditing of antimicrobial prescriptions to prevent their inappropriate use and unnecessary cost to the patients are required. The high percentage of inappropriate use of antimicrobials raises concerns about the development and spread of drug resistance, which must be addressed.

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.

Streptococcus suis infection: a series of 41 cases from Chiang Mai University Hospital.

PubMed

Wangkaew, Suparaporn; Chaiwarith, Romanee; Tharavichitkul, Prasit; Supparatpinyo, Khuanchai

2006-06-01

The objectives of this study were (1) to assess the clinical manifestations, treatment, and outcome of Streptococcus suis infection in adult patients in northern Thailand, (2) to evaluate the anti-microbial sensitivity pattern and (3) to determine the predicting factors of high mortality rate. A retrospective study was conducted at Chiang Mai University Hospital from May 2000 to December 2002. Anti-microbial susceptibility test was performed by agar disk diffusion and the minimal inhibitory concentration (MIC) by E-test. Forty-one patients (32 men and nine women, mean age 51 years) with S. suis infection were identified. Three patients had a history of exposure to pig or pork and one patient had a history of raw beef consumption. Clinical manifestations included infective endocarditis, meningitis, sepsis, spondylodiscitis, and endophthalmitis in 16, 13, 10, 1, and 1 patients, respectively. The overall mortality rate was 19.5%. On univariate analysis, low serum albumin, high serum total bilirubin, low platelet, and rapid onset of illness were significantly correlated with high mortality rate. All isolates were sensitive to penicillin (mean MIC90=0.027 microg/ml). S. suis infection is not uncommon in northern Thailand. High suspicion and early detection are important and could lead to the successful treatment.

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

Sales of veterinary antibacterial agents in nine European countries during 2005-09: trends and patterns.

PubMed

Grave, Kari; Greko, Christina; Kvaale, Mari K; Torren-Edo, Jordi; Mackay, David; Muller, Arno; Moulin, Gerard

2012-12-01

To identify trends and patterns of sales of veterinary antimicrobial agents in nine European countries during 2005-09 in order to document the situation. Existing sales data, in tonnes of active ingredients, of veterinary antimicrobial agents by class were collected from nine European countries in a standardized manner for the years 2005-09 (one country for 2006-09). A population correction unit (PCU) is introduced as a proxy for the animal population potentially treated with antimicrobial agents. The sales data are expressed as mg of active substance/PCU. Data coverage was reported to be 98%-100% for the nine countries. Overall, sales of veterinary antimicrobials agents, in mg/PCU, declined during the reporting period in the nine countries. Substantial differences in the sales patterns and in the magnitude of sales of veterinary antimicrobial agents, expressed as mg/PCU, between the nine countries are observed. The major classes sold were penicillins, sulphonamides and tetracyclines. The sales accounted for by the various veterinary antimicrobial agents have changed substantially for most countries. An increase in the sales of third- and fourth-generation cephalosporins and fluoroquinolones were observed for the majority of the countries. Through re-analysis of existing data by application of a harmonized approach, an overall picture of the trends in the sales of veterinary antimicrobial agents in the nine countries was obtained. Notable differences in trends in sales between the countries were observed. Further studies, preferably including data by animal species, are needed to understand the factors that explain these observations.

Antibiotic resistance patterns and occurrence of mecA gene in Staphylococcus intermedius strains of canine origin.

PubMed

Kizerwetter-Swida, M; Chrobak, D; Rzewuska, M; Binek, M

2009-01-01

We have evaluated 102 Staphylococcus intermedius isolates of canine origin for susceptibility to antimicrobial primary agents, i.e. penicillin, amoxicillin, amoxicillin with clavulanic acid, cefuroxime, trimethoprim/sulfonamides, neomycin, streptomycin, gentamicin, norfloxacin, tetracycline, vancomycin, erythromycin and secondary agents, i.e., chloramphenicol, ciprofloxacin, lincomycin, teicoplanin, rifampicin, imipenem, mupirocin. Antimicrobial sensitivity was examined using the disk diffusion method and performed according to NCCLS quidelines. Methicillin resistance was detected using the disk diffusion method with oxacillin, and the occurrence of mecA gene was detected by PCR. Resistance to streptomycin, penicillin, amoxicillin, neomycin, followed by tetracycline was predominant. From 14 mecA-positive strains, 12 were multidrug-resitant, and the remaining two showed atypical susceptibility. One strain resistant to oxacillin in the disc diffusion method was mecA-negative, suggesting a different mechanism of resistance. Our results indicate that the emergence of S. intermedius resistance to methicillin may be underestimated. In case of clinical multidrug-resitant S. intermedius isolates, resistance to methicillin should be considered.

In Vitro Antimicrobial Susceptibility Patterns of Blastocystis.

PubMed

Roberts, Tamalee; Bush, Stephen; Ellis, John; Harkness, John; Stark, Damien

2015-08-01

Blastocystis is the most common human enteric protist with controversial clinical significance. Metronidazole is considered a first-line treatment for Blastocystis infection; however, there has been increasing evidence for the lack of efficacy of this treatment. Treatment failure has been reported in several clinical cases, and recent in vitro studies have suggested the occurrence of metronidazole-resistant strains. In this study, we tested 12 Blastocystis isolates from 4 common Blastocystis subtypes (ST1, ST3, ST4, and ST8) against 12 commonly used antimicrobials (metronidazole, paromomycin, ornidazole, albendazole, ivermectin, trimethoprim-sulfamethoxazole [TMP-SMX], furazolidone, nitazoxanide, secnidazole, fluconazole, nystatin, and itraconazole) at 10 different concentrations in vitro. It was found that each subtype showed little sensitivity to the commonly used metronidazole, paromomycin, and triple therapy (furazolidone, nitazoxanide, and secnidazole). This study highlights the efficacy of other potential drug treatments, including trimethoprim-sulfamethoxazole and ivermectin, and suggests that current treatment regimens be revised. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Physiological and molecular characteristics of carbapenem resistance in Klebsiella pneumoniae and Enterobacter aerogenes.

PubMed

Pereira, Rito Santo; Dias, Vanessa Cordeiro; Ferreira-Machado, Alessandra Barbosa; Resende, Juliana Alves; Bastos, André Netto; Andrade Bastos, Lucas Quinet; Andrade Bastos, Victor Quinet; Bastos, Ricardo Villela; Da Silva, Vânia Lúcia; Diniz, Cláudio Galuppo

2016-06-30

Bacterial resistance is a growing concern in the nosocomial environment in which Klebsiella pneumoniae and Enterobacter aerogenes play an important role due to their opportunism and carbapenemase-production. This work aimed to evaluate physiological and molecular characteristics of carbapenem-resistant K. pneumoniae and E. aerogenes isolated in a Brazilian tertiary hospital. In total, 42 carbapenem-resistant bacteria isolated from clinical specimens were included (21 K. pneumoniae and 21 E. aerogenes). Drug-sensitive K. pneumoniae (n = 27) were also included. Antimicrobial susceptibility and biocide tolerance patterns, hemolytic activity, tolerance to oxidative stress, and aggregative ability were assessed. Genetic markers related to carbapenem resistance, or ESBL-production were screened by PCR. Compared to drug-sensitive strains, carbapenem-resistant K. pneumoniae were more tolerant to biocides and to oxidative stress, and they displayed an increase in biofilm formation. The genetic markers blaKPC (95.2%) and blaTEM (90.5%) were the most frequent. Among the carbapenem-resistant E. aerogenes strains, blaKPC, and blaTEM were detected in all bacteria. Drug-sensitive E. aerogenes were not isolated in the same period. blaSHV, blaVIM, and blaCTX markers were also observed among carbapenem-resistant bacteria. Results suggest that carbapenemase-producing enterobacteria might show peculiar characteristics regarding their physiology associated with their environmental persistency, virulence, and multidrug resistance. The observed phenomenon may have implications not only for antimicrobial chemotherapy, but also for the prognosis of infectious diseases and infection control.

In Vitro efficacy of antimicrobial extracts against the atypical ruminant pathogen Mycoplasma mycoides subsp. capri.

PubMed

Arjoon, Amanda V; Saylor, Charlotte V; May, Meghan

2012-10-02

Mycoplasmosis is a common infection in human and veterinary medicine, and is associated with chronic inflammation and high morbidity. Mycoplasma species are often intrinsically resistant to many conventional antimicrobial therapies, and the resistance patterns of pathogenic mycoplasmas to commonly used medicinal (antimicrobial) plant extracts are currently unknown. Aqueous extracts, ethanol extracts, or oils of the targeted plant species and colloidal silver were prepared or purchased. Activity against the wall-less bacterial pathogen Mycoplasma mycoides subsp. capri was determined and compared to activities measured against Escherichia coli and Bacillus subtilis. Antimicrobial susceptibility testing was performed by broth microdilution assays. The lethal or inhibitory nature of each extract was determined by subculture into neat growth medium. Growth of M. mycoides capri, E. coli, and B. subtilis was inhibited by elderberry extract, oregano oil, ethanol extract of oregano leaves, and ethanol extract of goldenseal root. No inhibition was seen with aqueous extract of astragalus or calendula oil. Growth of M. mycoides capri and B. subtilis was inhibited by ethanol extract of astragalus, whereas growth of E. coli was not. Similarly, M. mycoides capri and E. coli were inhibited by aqueous extract of thyme, but B. subtilis was unaffected. Only B. subtilis was inhibited by colloidal silver. Measured MICs ranged from 0.0003 mg/mL to 3.8 mg/mL. Bacteriostatic and bactericidal effects differed by species and extract. The atypical pathogen M. mycoides capri was sensitive to extracts from many medicinal plants commonly used as antimicrobials in states of preparation and concentrations currently available for purchase in the United States and Europe. Variation in bacteriostatic and bactericidal activities between species and extracts indicates that multiple effecter compounds are present in these plant species.

In Vitro efficacy of antimicrobial extracts against the atypical ruminant pathogen Mycoplasma mycoides subsp. capri

PubMed Central

2012-01-01

Background Mycoplasmosis is a common infection in human and veterinary medicine, and is associated with chronic inflammation and high morbidity. Mycoplasma species are often intrinsically resistant to many conventional antimicrobial therapies, and the resistance patterns of pathogenic mycoplasmas to commonly used medicinal (antimicrobial) plant extracts are currently unknown. Methods Aqueous extracts, ethanol extracts, or oils of the targeted plant species and colloidal silver were prepared or purchased. Activity against the wall-less bacterial pathogen Mycoplasma mycoides subsp. capri was determined and compared to activities measured against Escherichia coli and Bacillus subtilis. Antimicrobial susceptibility testing was performed by broth microdilution assays. The lethal or inhibitory nature of each extract was determined by subculture into neat growth medium. Results Growth of M. mycoides capri, E. coli, and B. subtilis was inhibited by elderberry extract, oregano oil, ethanol extract of oregano leaves, and ethanol extract of goldenseal root. No inhibition was seen with aqueous extract of astragalus or calendula oil. Growth of M. mycoides capri and B. subtilis was inhibited by ethanol extract of astragalus, whereas growth of E. coli was not. Similarly, M. mycoides capri and E. coli were inhibited by aqueous extract of thyme, but B. subtilis was unaffected. Only B. subtilis was inhibited by colloidal silver. Measured MICs ranged from 0.0003 mg/mL to 3.8 mg/mL. Bacteriostatic and bactericidal effects differed by species and extract. Conclusions The atypical pathogen M. mycoides capri was sensitive to extracts from many medicinal plants commonly used as antimicrobials in states of preparation and concentrations currently available for purchase in the United States and Europe. Variation in bacteriostatic and bactericidal activities between species and extracts indicates that multiple effecter compounds are present in these plant species. PMID:23031072

Antimicrobial stewardship in Victorian hospitals: a statewide survey to identify current gaps.

PubMed

James, Rodney S; McIntosh, Kylie A; Luu, Susan B; Cotta, Menino O; Marshall, Caroline; Thursky, Karin A; Buising, Kirsty L

2013-11-18

To determine antimicrobial stewardship (AMS) activities currently being undertaken at Victorian hospitals, identifying gaps when assessed against the Australian Commission on Safety and Quality in Health Care criteria for effective AMS. A survey open to all Victorian health services, conducted between January and March 2012. Availability of the endorsed prescribing guidelines, antimicrobial prescribing policies, formularies, approval systems for restricted antimicrobials, procedures for postprescription review, auditing and selective reporting of sensitivities. Response rates were 96.4% for public health services and 67.7% for private hospitals. Guidelines were available at all public and 88.1% of private hospitals, and 90.6% of public metropolitan, 45.7% of public regional and 21.4% of private hospitals had antimicrobial prescribing policies. Antimicrobial approval systems were used in 93.8% of public metropolitan, 17.3% of public regional and 4.8% of private hospitals. Prescribing audits were conducted by 62.5% of public metropolitan, 35.8% public regional and 52.4% of private hospitals. Nearly all hospitals had selective laboratory reporting of antimicrobial sensitivities. Few hospitals had dedicated funding for AMS personnel. We identified wide differences between hospital AMS activities. Additional support for AMS is particularly required in the public regional and private hospital sectors, principally in the key areas of policy development, antimicrobial approval systems, prescription review and auditing. Further research is required to develop recommendations for implementation of AMS within the regional and private hospital settings.

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.

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.

Further characterization of porcine Brachyspira hyodysenteriae isolates with decreased susceptibility to tiamulin.

PubMed

Karlsson, M; Aspán, A; Landén, A; Franklin, A

2004-04-01

Brachyspira hyodysenteriae is the causative agent of swine dysentery, a severe diarrhoeal disease in pigs. Few drugs are available to treat the disease, owing to both antimicrobial resistance and withdrawal of drugs authorized for use in pigs. Tiamulin is the drug of choice in many countries, but isolates with decreased susceptibility have recently been reported. The mechanism of tiamulin resistance in B. hyodysenteriae is not known and this facet is essential to understand the dissemination of the trait. To study the resistance epidemiology of B. hyodysenteriae, further characterization of a set of isolates from Germany (n = 16) and the UK (n = 6) with decreased susceptibility to tiamulin was performed. The relatedness between the isolates was studied by comparing PFGE patterns, and the in vitro susceptibility to five other antimicrobials (aivlosin, doxycycline, salinomycin, chloramphenicol and avilamycin) was also determined. For comparison of the antimicrobial-susceptibility pattern, Swedish (n = 20) and British (n = 4) tiamulin-susceptible isolates were tested. The German isolates represented several different PFGE patterns, indicating that tiamulin usage has been sufficient to select clones with decreased tiamulin susceptibility at different farms in Germany. The PFGE pattern for the six British isolates with decreased tiamulin susceptibility was identical to that of the German isolates, and they had a similar antimicrobial-susceptibility pattern, except for resistance to aivlosin, which was only found in a few German isolates. No other co-resistance with tiamulin was found.

Corynebacterium species causing breast abscesses among patients attending a tertiary care hospital in Chennai, South India.

PubMed

Poojary, Indira; Kurian, Ann; V A, Jayalekshmi; Devapriya J, Debora; M A, Thirunarayan

2017-07-01

Corynebacterium species other than Corynebacterium diphtheriae were mostly considered contaminants in the past, but there are reports of their association with wide variety of human infections lately. In this study, we look into Corynebacterium species isolated from breast abscess patients and assess their antimicrobial susceptibility pattern and treatment outcomes. Pus samples from suspected breast abscess cases were examined from October 2014 to September 2015. Growth of Gram-positive bacilli morphologically resembling Corynebacterium species were identified by matrix-assisted laser desorption/ionization- time of flight mass spectrometry identifications generated by the Vitek MS system (bioMérieux, France) (MALDI-TOF Vitek MS system) and antimicrobial susceptibility was done. Corynebacterium species were isolated from 10 female breast abscess patients with median age of 36 years (range 25-59 years). Out of the 10 isolates four isolates were identified as C. kroppenstedtii; one isolate as C. striatum and five isolates were identified as C. amycolatum/C.xerosis. Out of four isolates of C .kroppenstedtii, two isolates were resistant to cotrimoxazole and one C. striatum isolate was resistant to penicillin, ampicillin, cotrimoxazole and clindamycin. Of the five isolates identified as C amycolatum/C xerosis, all were sensitive to vancomycin and linezolid but resistant to clindamycin. All the patients were treated with incision, drainage and antibiotics based on the sensitivity pattern; eight were cured and two patients did not come for follow-up. Corynebacterium species should be considered one of the causative agents of breast abscess and a varied susceptibility profile amongst the different species makes susceptibility testing important. Identification by MALDI-TOF Vitek MS system may not differentiate between C. amycolatum and C. xerosis.

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.

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.

Association of Urinary Tract Infection in Married Women Presenting with Urinary Incontinence in a Hospital based Population.

PubMed

Subramaniam, Jayakumar; Eswara, Shilpalakshmiprasad; Yesudhason, Bineshlal

2016-03-01

Urinary incontinence (UI) is increasingly recognized as a significant health problem, which remains a hygienic as well as social problem. Women have higher risk of developing incontinence in their lifetime compared with men. Urinary tract infection can increase the incidence of incontinence. Present study was undertaken to assess the association of UTI in married women who presented with UI. The present study was aimed to identify the patients (married women) with complaints of UI and determining its association with UTI; and to identify the causative organism for the UTI along with its antimicrobial susceptibility pattern. This is a cross-sectional, non-randomized study of 107 married women with UI, who attended outpatient department in our hospital. Mid-stream urine (MSU) samples were collected from these patients with positive history of incontinence. Screening of urine for significant bacteriuria and culture to identify the etiological agents were performed followed by evaluation of their antimicrobial susceptibility profiles using Kirby Bauer disc diffusion method. Overall 25.2% of patients with incontinence had a positive urine culture. History of UTI was elicited in around 38.3% of patients, among which 15% had positive urine culture and 10.3% of the patients who did not have a history had positive culture. Escherichia coli was the commonest causative organism (66.6) causing UTI, followed by Enterococcus spp. (22.3%), Klebsiella pneumoniae (7.4%) and Proteus mirabilis (3.7%). The antimicrobial susceptibility pattern for Escherichia coli showed high sensitivity to Nitrofurantoin (94.4%) and high resistance to Ampicillin (94.4%). Our study revealed one in every four incontinent patients had UTI and almost half of them suffered from previous episodes of UTI. Thus appropriate correction of the existing UTI can help in the treatment of UI.

Biofilm formation and antimicrobial sensitivity of lactobacilli contaminants from sugarcane-based fuel ethanol fermentation.

PubMed

Dellias, Marina de Toledo Ferraz; Borges, Clóvis Daniel; Lopes, Mário Lúcio; da Cruz, Sandra Helena; de Amorim, Henrique Vianna; Tsai, Siu Mui

2018-02-24

Industrial ethanol fermentation is subject to bacterial contamination that causes significant economic losses in ethanol fuel plants. Chronic contamination has been associated with biofilms that are normally more resistant to antimicrobials and cleaning efforts than planktonic cells. In this study, contaminant species of Lactobacillus isolated from biofilms (source of sessile cells) and wine (source of planktonic cells) from industrial and pilot-scale fermentations were compared regarding their ability to form biofilms and their sensitivity to different antimicrobials. Fifty lactobacilli were isolated and the most abundant species were Lactobacillus casei, Lactobacillus fermentum and Lactobacillus plantarum. The majority of the isolates (87.8%) were able to produce biofilms in pure culture. The capability to form biofilms and sensitivity to virginiamycin, monensin and beta-acids from hops, showed inter- and intra-specific variability. In the pilot-scale fermentation, Lactobacillus brevis, L. casei and the majority of L. plantarum isolates were less sensitive to beta-acids than their counterparts from wine; L. brevis isolates from biofilms were also less sensitive to monensin when compared to the wine isolates. Biofilm formation and sensitivity to beta-acids showed a positive and negative correlation for L. casei and L. plantarum, respectively.

Comparison of pathogens and their antimicrobial resistance patterns in paediatric, adult and elderly patients in Canadian hospitals.

PubMed

Adam, Heather J; Baxter, Melanie R; Davidson, Ross J; Rubinstein, Ethan; Fanella, Sergio; Karlowsky, James A; Lagacé-Wiens, Philippe R S; Hoban, Daryl J; Zhanel, George G

2013-05-01

The purpose of this study was to describe the association between age groups and antimicrobial resistance in the most commonly identified pathogens in Canadian hospitals. Between 2007 and 2011, 27,123 clinically significant isolates, comprising 3580 isolates from children ≤ 18 years old, 12,119 isolates from adults 19-64 years old and 11,424 isolates from elderly patients aged ≥ 65 years old, were collected as part of the CANWARD surveillance study from tertiary-care centres across Canada. Antimicrobial susceptibility testing was performed according to CLSI guidelines. A multifactorial logistic regression model was used to determine the impact of demographic factors, including age groups, on antimicrobial resistance. Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae and Pseudomonas aeruginosa were in the top five organisms for all of the age groups. The proportions of S. aureus that were methicillin resistant, enterococci that were vancomycin resistant and E. coli that produced extended-spectrum β-lactamases were 11.2%, 0.7% and 1.0% for children, 22.8%, 4.6% and 4.3% for adults, and 28.0%, 3.8% and 4.9% for the elderly, respectively. Notable age-related differences in antimicrobial resistance patterns included the following: significantly less methicillin, clindamycin, clarithromycin and trimethoprim/sulfamethoxazole resistance in S. aureus from children; for E. coli, higher cefazolin and ciprofloxacin resistance in the elderly and less ceftriaxone, ciprofloxacin and gentamicin resistance in isolates from children; more S. pneumoniae isolates with penicillin MICs >1 mg/L in children; and for P. aeruginosa, higher resistance rates for meropenem, ciprofloxacin and levofloxacin in adults. The assessment of antimicrobial susceptibility patterns by age group revealed that resistance rates are often higher in the older age groups; however, considerable variability in age-specific resistance trends for different pathogen-antimicrobial combinations was noted.

Pathogen Distribution and Antimicrobial Resistance Among Pediatric Healthcare-Associated Infections Reported to the National Healthcare Safety Network, 2011-2014.

PubMed

Lake, Jason G; Weiner, Lindsey M; Milstone, Aaron M; Saiman, Lisa; Magill, Shelley S; See, Isaac

2018-01-01

OBJECTIVE To describe pathogen distribution and antimicrobial resistance patterns for healthcare-associated infections (HAIs) reported to the National Healthcare Safety Network (NHSN) from pediatric locations during 2011-2014. METHODS Device-associated infection data were analyzed for central line-associated bloodstream infection (CLABSI), catheter-associated urinary tract infections (CAUTI), ventilator-associated pneumonia (VAP), and surgical site infection (SSI). Pooled mean percentage resistance was calculated for a variety of pathogen-antimicrobial resistance pattern combinations and was stratified by location for device-associated infections (neonatal intensive care units [NICUs], pediatric intensive care units [PICUs], pediatric oncology and pediatric wards) and by surgery type for SSIs. RESULTS From 2011 to 2014, 1,003 hospitals reported 20,390 pediatric HAIs and 22,323 associated pathogens to the NHSN. Among all HAIs, the following pathogens accounted for more than 60% of those reported: Staphylococcus aureus (17%), coagulase-negative staphylococci (17%), Escherichia coli (11%), Klebsiella pneumoniae and/or oxytoca (9%), and Enterococcus faecalis (8%). Among device-associated infections, resistance was generally lower in NICUs than in other locations. For several pathogens, resistance was greater in pediatric wards than in PICUs. The proportion of organisms resistant to carbapenems was low overall but reached approximately 20% for Pseudomonas aeruginosa from CLABSIs and CAUTIs in some locations. Among SSIs, antimicrobial resistance patterns were similar across surgical procedure types for most pathogens. CONCLUSION This report is the first pediatric-specific description of antimicrobial resistance data reported to the NHSN. Reporting of pediatric-specific HAIs and antimicrobial resistance data will help identify priority targets for infection control and antimicrobial stewardship activities in facilities that provide care for children. Infect Control Hosp Epidemiol 2018;39:1-11.

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.

Plantaricin A, a cationic peptide produced by Lactobacillus plantarum, permeabilizes eukaryotic cell membranes by a mechanism dependent on negative surface charge linked to glycosylated membrane proteins.

PubMed

Sand, Sverre L; Nissen-Meyer, Jon; Sand, Olav; Haug, Trude M

2013-02-01

Lactobacillus plantarum C11 releases plantaricin A (PlnA), a cationic peptide pheromone that has a membrane-permeabilizing, antimicrobial effect. We have previously shown that PlnA may also permeabilize eukaryotic cells, with a potency that differs between cell types. It is generally assumed that cationic antimicrobial peptides exert their effects through electrostatic attraction to negatively charged phospholipids in the membrane. The aim of the present study was to investigate if removal of the negative charge linked to glycosylated proteins at the cell surface reduces the permeabilizing potency of PlnA. The effects of PlnA were tested on clonal rat anterior pituitary cells (GH(4) cells) using patch clamp and microfluorometric techniques. In physiological extracellular solution, GH(4) cells are highly sensitive to PlnA, but the sensitivity was dramatically reduced in solutions that partly neutralize the negative surface charge of the cells, in agreement with the notion that electrostatic interactions are probably important for the PlnA effects. Trypsination of cells prior to PlnA exposure also rendered the cells less sensitive to the peptide, suggesting that negative charges linked to membrane proteins are involved in the permeabilizing action. Finally, pre-exposure of cells to a mixture of enzymes that split carbohydrate residues from the backbone of glycosylated proteins also impeded the PlnA-induced membrane permeabilization. We conclude that electrostatic attraction between PlnA and glycosylated membrane proteins is probably an essential first step before PlnA can interact with membrane phospholipids. Deviating glycosylation patterns may contribute to the variation in PlnA sensitivity of different cell types, including cancerous cells and their normal counterparts. Copyright © 2012 Elsevier B.V. All rights reserved.

Antimicrobial resistance patterns, clinical features, and risk factors for septic shock and death of nosocomial E coli bacteremia in adult patients with hematological disease: A monocenter retrospective study in China.

PubMed

Ma, Jie; Li, Ning; Liu, Yajie; Wang, Chong; Liu, Xiaoyan; Chen, Shengmei; Xie, Xinsheng; Gan, Silin; Wang, Meng; Cao, Weijie; Wang, Fang; Liu, Yanfan; Wan, Dingming; Sun, Ling; Sun, Hui

2017-05-01

The aim of this retrospective analysis was to evaluate the antimicrobial resistance, clinical features, and risk factors for septic shock and death of nosocomial E coli bacteremia in adult patients in a single hematological center in China. A retrospective case-control study of 157 adult hematological patients with 168 episodes of E coli bacteremia was initiated from April 2012 to July 2015. Antimicrobial susceptibility as well as antimicrobial co-resistance rates were analyzed. Clinical features and outcomes were also studied. In addition, risk factors for septic shock and death were investigated. Among the 553 positive blood isolates during the study period, the prevalence of E coli was 33.3% and ESBL production strains represented 61.9% of those examined. In all the E coli strains isolated, 85.6% were multidrug-resistance (MDR), 2.4% were extensive drug resistance (XDR), and 6.0% were resistant to carbapenems. More MDR phenotype was noted in ESBL-EC strains (98.6% vs 62.8%, P<.001) and isolates from neutropenic patients (98.6% vs 62.8%, P < .001). In the antimicrobial susceptibility test, carbapenems and amikacin exhibited not only higher in vitro activity against E coli (94.0% and 92.0%, respectively), but lower co-resistance rates to other antibiotics. Carbapenem resistant strains retained full sensitivity to tigecycline and 60% to amikacin. Piperacillin/tazobatam was the third sensitive drug to both ESBL-EC (77.1%) and non-ESBL-EC (86.0%). In our series, 81.6% episodes received appropriate initial antibiotic treatment and no significant decrease in it was found in bacteremia due to ESBL E coli and patients with neutropenia, septic shock. Septic shock was noted in 15.5% patients and the overall 30-day mortality rate was 21.7%. Multivariate analysis revealed that induction chemotherapy (OR 2.126; 95% CI 1.624-11.332; P = .003) and polymicrobial infection (OR 3.628; 95% CI 1.065-21.219; P = .041) were risk factors for septic shock, whereas male (OR 2.223; 95% CI 1.132-12.022; P < .01) and septic shock (OR 52.359; 95% CI 19.951-292.690; P = .030) were risk factors for death.In the hematology department, ESBL-producing and MDR are widely prevalent in E coli bacteremia which is still a major life-threatening problem, especially for patients with septic shock. For empirical antimicrobial therapy, combination based on aminoglycoside, especially amikacin, will be helpful to increase the antimicrobial coverage against ESBL-EC while combining tigecycline with aminoglycoside should be considered for seriously carbapenem-resistant infectious patients.

Adaptive ingredients against food spoilage in Japanese cuisine.

PubMed

Ohtsubo, Yohsuke

2009-12-01

Billing and Sherman proposed the antimicrobial hypothesis to explain the worldwide spice use pattern. The present study explored whether two antimicrobial ingredients (i.e. spices and vinegar) are used in ways consistent with the antimicrobial hypothesis. Four specific predictions were tested: meat-based recipes would call for more spices/vinegar than vegetable-based recipes; summer recipes would call for more spices/vinegar than winter recipes; recipes in hotter regions would call for more spices/vinegar; and recipes including unheated ingredients would call for more spices/vinegar. Spice/vinegar use patterns were compiled from two types of traditional Japanese cookbooks. Dataset I included recipes provided by elderly Japanese housewives. Dataset II included recipes provided by experts in traditional Japanese foods. The analyses of Dataset I revealed that the vinegar use pattern conformed to the predictions. In contrast, analyses of Dataset II generally supported the predictions in terms of spices, but not vinegar.

Comparison of antemortem antimicrobial treatment regimens to antimicrobial susceptibility patterns of postmortem lung isolates from feedlot cattle with bronchopneumonia.

PubMed

Lamm, Catherine G; Love, Brenda C; Krehbiel, Clint R; Johnson, Nicholas J; Step, Douglas L

2012-03-01

A retrospective study was performed to compare the treatment regimens in feedlot cattle that died with bovine respiratory disease (BRD) to the antimicrobial susceptibility patterns of the microorganisms isolated from lungs. Forty-three cattle submitted by the Willard Sparks Beef Research Center (WSBRC) to the Oklahoma Animal Disease Diagnostic Laboratory for postmortem examination during 2007 had bronchopneumonia (acute = 16, subacute = 5, or chronic = 22). Lungs from cattle were cultured aerobically (40 cattle) and for Mycoplasma spp. (34 cattle). Susceptibility panels were performed. At least 1 BRD pathogen (Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Mycoplasma bovis, or Arcanobacterium pyogenes) was isolated from 39 cattle, and 77% (30/39) had multiple organisms recovered. Mycoplasmal infections were common (25/34) and a major component of mixed infections (24/25). The majority (60%) of the M. haemolytica, P. multocida, and H. somni isolates were resistant to tetracycline. Most of the H. somni isolates (67%) were susceptible to tilmicosin (Ti), enrofloxacin (En), ceftiofur (Ce), and florfenicol, despite extensive treatment with Ti, En, and Ce (75% of isolates were from cattle that received each antimicrobial once). Most of the M. haemolytica (65%) and P. multocida (79%) isolates were susceptible to En and Ce, despite antemortem treatment of cattle with these antimicrobials. Hence, the current study reports a discrepancy between the antemortem treatment of clinical BRD and the susceptibility patterns of the bacteria isolated from lungs postmortem. Based on these findings, factors other than antimicrobial resistance are playing a role in the death of feedlot cattle with BRD.

Prevalence of multiple drug resistant Streptococcus suis in and around Guwahati, India.

PubMed

Devi, Mrinalee; Dutta, Jyoti B; Rajkhowa, Swaraj; Kalita, Dhireswar; Saikia, Girindra Kumar; Das, Bipin Chandra; Hazarika, Razibuddin Ahmed; Mahato, Gauranga

2017-05-01

This study was conducted to determine the prevalence and antimicrobial susceptibility of Streptococcus suis and their resistance patterns isolated from both clinically healthy carriers and diseased pigs in and around Guwahati, Assam, India. A total of 497 samples were collected during October, 2012, to April, 2014, from clinically healthy (n=67) and diseased (n=230) pigs of varying age and either sex maintained under organized and unorganized farming systems. Samples were processed for isolation and identification of S. suis by biochemical characterization and polymerase chain reaction targeting the housekeeping gene glutamate dehydrogenase. In vitro antimicrobial susceptibility of the recovered isolates against nine antibiotic groups comprising 17 antimicrobial agents was studied by standard method. Of the 497 samples examined, 7 (1.41%) isolates were confirmed to be S. suis of which 5 (1.87%) and 2 (0.87%) were derived from clinically healthy and diseased pigs, respectively. All the isolates were susceptible to gentamicin, amikacin, and erythromycin (100%) followed by the penicillin group and enrofloxacin (85.71%), ceftriaxone, doxycycline HCL, ofloxacin and chloramphenicol (71.43%), to kanamycin, clindamycin and co-trimoxazole (42.85%). The isolates showed least susceptibility to cefalexin, tetracycline and streptomycin (28.57%). All the five S. suis isolates from clinically healthy pigs were susceptible to penicillin G, amoxyclav, doxycycline HCl, gentamicin, amikacin and erythromycin, 80.00% isolates susceptible to ampicillin, enrofloxacin and ofloxacin, 60.00% to ceftriaxone, kanamycin and chloramphenicol, 40% to cefalexin, tetracycline, clindamycin and co-trimoxazole, respectively. Only 20.00% isolates were susceptible to streptomycin. Both the isolates recovered from diseased pigs were susceptible to ampicillin, ceftriaxone, gentamicin, amikacin, enrofloxacin, erythromycin, and clindamycin. On the other hand, both the isolates were resistant to cefalexin, tetracycline, doxycycline HCL, and kanamycin. Altogether five different resistance patterns (multi-drug resistance) were observed. Of the seven S. suis isolates, two isolates were susceptible to all the 17 antimicrobial agents, one isolate was resistant to four antimicrobial agents, two isolates to seven agents, one isolate to nine agents, and one isolate exhibited resistance to 14 antimicrobial agents. This study was conducted to determine the prevalence of S. suis in clinically healthy and diseased pigs and their antimicrobial susceptibility patterns. All the isolates were susceptible to gentamicin, amikacin and erythromycin, and most of them were resistant to cefalexin, tetracycline and streptomycin. Five different patterns of antimicrobial resistance (multi-drug resistance) were observed.

Prevalence, resistance patterns, and risk factors for antimicrobial resistance in bacteria from retail chicken meat in Colombia.

PubMed

Donado-Godoy, Pilar; Byrne, Barbara A; León, Maribel; Castellanos, Ricardo; Vanegas, Consuelo; Coral, Adriana; Arevalo, Alejandra; Clavijo, Viviana; Vargas, Mercedes; Romero Zuñiga, Juan J; Tafur, McAllister; Pérez-Gutierrez, Enrique; Smith, Woutrina A

2015-04-01

As a step toward implementing the Colombian Integrated Program for Antimicrobial Resistance Surveillance (COIPARS), this study aimed to establish the baseline antimicrobial resistance patterns of Salmonella serovars, Escherichia coli, and Enterococcus spp. isolates in retail poultry meat from independent stores and from a main chain distributor center. MICs of the isolates were determined for antimicrobials used both in humans and animals, using an automated system. Salmonella serovars were isolated from 26% of the meat samples and E. coli from 83%, whereas Enterococcus faecalis and Enterococcus faecium were detected in 81 and 13% of the meat samples, respectively. A principal finding of concern in this study was that almost 98% of isolates tested were multidrug resistant. Ceftiofur, enrofloxacin, nalidixic acid, and tetracycline were the antimicrobials that showed the highest frequency of resistance among Salmonella and E. coli isolates. For enterococci, 61.5% of E. faecium isolates were found to be resistant to quinupristin-dalfopristin; this is significant because it is used to treat nosocomial infections when vancomycin resistance is present. Vancomycin resistance was detected in 4% of the E. faecalis isolates. The results of our study highlight the need for rapid implementation of an integrated program for surveillance of antimicrobial resistance by the Colombian authorities in order to monitor trends, raise awareness, and help promote practices to safeguard later generation antimicrobial agents.

Survey on antimicrobial prescribing patterns in small animal veterinary practice in Emilia Romagna, Italy.

PubMed

Barbarossa, A; Rambaldi, J; Miraglia, V; Giunti, M; Diegoli, G; Zaghini, A

2017-07-15

This investigation provides for the first time a general view of the prescribing patterns of antimicrobials in small animal practice in Emilia Romagna, Italy. In the context of a project on antimicrobial resistance managed by the Regional Veterinary Service, veterinary clinicians were invited to voluntarily complete an online questionnaire. This was designed to gather information on antimicrobial prescribing practices and biosecurity measures and to understand the perception of the issue specific to this region of Italy. In total, 266 questionnaires correctly completed were collected. Although clinicians seemed to follow different approaches when using antimicrobials, the data analysis revealed a general awareness on resistance. Penicillins were the most commonly prescribed class, followed by (fluoro)quinolones and cephalosporins. Among those who use laboratory testing more or less frequently (microbiological analysis and susceptibility testing) to support their prescribing habits, only 7 per cent make a habit of always waiting for the results before starting the treatment. Seventy-eight per cent of the respondents declared the use of antimicrobials licensed for human beings. Biosecurity measures were carefully taken into account by the majority of the veterinarians. The results identified the antimicrobial classes that are commonly prescribed and highlighted that perioperative hygiene measures and the use of laboratory diagnosis are critical aspects that need to be emphasised in drawing up guidelines on the prudent use of these drugs in pets.

Evaluation of anti-microbial activity of spore powder of Ganoderma lucidum on clinical isolates of Prevotella intermedia: A pilot study.

PubMed

Nayak, Ranganath N; Dixitraj, P T; Nayak, Aarati; Bhat, Kishore

2015-09-01

This study aimed at evaluating the anti-microbial activity of spore powder of Ganoderma lucidum on Prevotella intermedia isolated from subgingival plaque from chronic periodontitis patients. Written informed consent was obtained from each subject enrolled in the study. The Institutional Ethics Committee granted the ethical clearance for the study. This study included 20 patients diagnosed with chronic periodontitis. Pooled subgingival plaque samples were collected using sterile curettes from the deepest sites of periodontal pockets. The collected samples were then transported in 1 mL of reduced transport fluid. The organisms were cultured and confirmed. These organisms were then used for minimum inhibitory concentration (MIC) procedure. Mean of the MIC value obtained was calculated. Thirteen out of the 20 clinical samples were tested that showed sensitivity at various concentrations. Five samples showed sensitivity at all concentrations. Twelve samples showed sensitivity at 8 mcg/ml. Eleven samples showed sensitivity at 4 mcg/ml, 8 samples showed sensitivity at 2 mcg/ml, and 5 samples showed sensitivity even at 1 mcg/ml. Mean MIC value of G. lucidum spore powder for P. intermedia obtained was 3.62 mcg/ml. G. lucidum with its multipotential bioactivity could be used as an anti-microbial, in conjunction with conventional therapy in periodontal disease.

40 CFR 158.2270 - Post-application exposure.

Code of Federal Regulations, 2013 CFR

2013-07-01

... and the human activities associated with the pesticide's use pattern can lead to potential adverse...) Occupational human post-application or bystander exposure to residues of antimicrobial pesticides could occur... human post-application or bystander exposure to residues of antimicrobial pesticides could occur...

40 CFR 158.2270 - Post-application exposure.

Code of Federal Regulations, 2014 CFR

2014-07-01

... and the human activities associated with the pesticide's use pattern can lead to potential adverse...) Occupational human post-application or bystander exposure to residues of antimicrobial pesticides could occur... human post-application or bystander exposure to residues of antimicrobial pesticides could occur...

Treatment of feline giardiasis during an outbreak of diarrhoea in a cattery: potential effects on faecal Escherichia coli resistance patterns.

PubMed

Tysnes, Kristoffer Relling; Luyckx, Katrien; Cantas, Leon; Robertson, Lucy J

2016-08-01

An outbreak of diarrhoea involving 16 cats at a cattery in Norway was investigated. Treatment and control of the outbreak were the primary objectives, but the effects of treatment on the antimicrobial resistance profiles of Escherichia coli isolated from faeces were also investigated. Faecal samples were investigated for Giardia cysts by immunofluorescence microscopy, and multi-locus genotyping was performed to determine the Giardia genotype. Faecal E coli were assessed, before and after treatment for giardiasis, for antimicrobial resistance. The outbreak was probably caused by Giardia duodenalis, Assemblage F. Although infection was eliminated in most cats following treatment with fenbendazole, over 30% of the infected cats required a second treatment round (combined fenbendazole and metronidazole). Investigation of sensitivity to antibacterial drugs of E coli that had been isolated both prior to and following treatment demonstrated that fenbendazole treatment may select for resistant bacteria. Controlling Giardia infections in dense cat populations can be challenging, and requires strict hygiene measures. In cases where fenbendazole alone does not result in treatment success, a combination treatment with fenbendazole and metronidazole may be effective. Although this study did not include untreated controls, we suggest that the potential for changes in gut microbiota and antimicrobial resistance development should be considered when choosing antiprotozoal drugs, particularly in cases of treatment failure and where repeat treatment is required. © ISFM and AAFP 2015.

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.

Temporal trends and patterns in antimicrobial resistant Gram-negative bacteria implicated in intensive care unit-acquired infections: a cohort-based surveillance study in Istanbul, Turkey.

PubMed

Durdu, Bulent; Kritsotakis, Evangelos I; Lee, Andrew C K; Torun, Perihan; Hakyemez, Ismail N; Gultepe, Bilge; Aslan, Turan

2018-05-08

This study assessed trends and patterns in antimicrobial resistant intensive care unit (ICU)-acquired infections caused by Gram-negative bacteria (GNB) in Istanbul, Turkey. Bacterial culture and antibiotic susceptibility data were collected for all GNB causing nosocomial infections in five adult ICUs of a large university hospital during 2012-2015. Multi-resistance patterns were categorised as multidrug (MDR), extensively-drug (XDR) and pandrug (PDR)-resistance. Patterns and trends were assessed using seasonal decomposition and regression analyses. Of 991 pathogenic GNB recorded, most frequent were Acinetobacter baumannii (35%), Klebsiella species (27%), Pseudomonas aeruginosa (18%), Escherichia coli (7%) and Enterobacter species (4%). The overall infection rate decreased by 41% from 18.4 to 10.9 cases per 1000 patient-days in 2012 compared to 2015 (p <0.001), mostly representing decreases in bloodstream infections and pneumonias by A. baumannii and P. aeruginosa. XDR proportion in A.baumannii increased from 52% in 2012 to 72% in 2015, but only one isolate was colistin-resistant. Multi-resistance patterns remained stable in Klebsiella, with overall XDR and possible PDR proportions of 14% and 2%, respectively. A back-to-susceptibility trend was noted for P. aeruginosa in which the non-MDR proportion increased from 53% in 2012 to 71% in 2015. 88% of E.coli and 40% of Enterobacter isolates were MDR, but none was XDR. Antimicrobial resistance patterns in pathogenic GNB continuously change over time and may not reflect single-agent resistance trends. The proportionate amount of antimicrobial-resistant GNB may persist despite overall decreasing infection rates. Timely regional surveillance data are thus imperative for optimal infection control. Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Phytochemical Screening and Antimicrobial Properties of a Common Brand of Black Tea (Camellia sinensis) Marketed in Nigerian Environment.

PubMed

Olosunde, O Funmilayo; Abu-Saeed, Kamaldeen; Abu-Saeed, Muhammad Buhari

2012-01-01

This study is aimed at determining chemical constituents and antimicrobial activities of a common brand of black tea (Lipton®) in Nigeria. Standard methods were employed for testing carbohydrates, tannins, saponins, flavonoids, alkaloids, steroids and terpenes in the tea. Antimicrobial activities of methanolic and aqueous extracts of the tea on four standard strains of organisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis were also determined by standard methods. RESULTs showed that the tea contains tannin and reducing sugar. Concentrations of 1%, 2%, 4%, 6%, 8% and 10% aqueous and methanolic extract of black tea were prepared and their zones of inhibition determined against the four test organisms using the cup plate method. This was compared with zones for standard disc Gentamicin (10 µg) and Erythromycin (15 µg). Pseudomonas aeruginosa was sensitive to 2% to 10% aqueous extracts and intermediate to 6%, 8% and 10% methanolic extracts. E. coli was intermediately sensitive to 6%, 8% and 10% aqueous extract and 2% to 10% methanolic extracts. B. subtilis was intermediately sensitive to 4%, 6% and 8% aqueous extract and 4% to 10% methanolic extract but sensitive to 10% aqueous extract. Staph.aureus was intermediately sensitive to 4% to 10% aqueous extracts and 2% to 10% methanolic extracts. B. subtilis had the lowest MIC values of both aqueous and methanolic extracts. In conclusion, this study has shown that Lipton® has antimicrobial properties on E.coli, Staph.aureus, B.subtilis and Ps.aeruginosa and contains tannin and reducing sugar.

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.

[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.

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

Antimicrobial Drug Use and Resistance in Europe

PubMed Central

van de Sande-Bruinsma, Nienke; Verloo, Didier; Tiemersma, Edine; Monen, Jos; Goossens, Herman; Ferech, Matus

2008-01-01

Our study confronts the use of antimicrobial agents in ambulatory care with the resistance trends of 2 major pathogens, Streptococcus pneumoniae and Escherichia coli, in 21 European countries in 2000–2005 and explores whether the notion that antimicrobial drug use determines resistance can be supported by surveillance data at national aggregation levels. The data obtained from the European Surveillance of Antimicrobial Consumption and the European Antimicrobial Resistance Surveillance System suggest that variation of consumption coincides with the occurrence of resistance at the country level. Linear regression analysis showed that the association between antimicrobial drug use and resistance was specific and robust for 2 of 3 compound pathogen combinations, stable over time, but not sensitive enough to explain all of the observed variations. Ecologic studies based on routine surveillance data indicate a relation between use and resistance and support interventions designed to reduce antimicrobial drug consumption at a national level in Europe. PMID:18976555

Antimicrobial resistance patterns of bacteria isolated from canine urinary samples submitted to a New Zealand veterinary diagnostic laboratory between 2005-2012.

PubMed

McMeekin, C H; Hill, K E; Gibson, I R; Bridges, J P; Benschop, J

2017-03-01

To identify and describe culture and antimicrobial resistance (AMR) patterns in bacteria isolated from canine urinary samples submitted to a New Zealand veterinary diagnostic laboratory. Records from a veterinary diagnostic laboratory were examined for bacterial isolates cultured from canine urine samples between January 2005 and December 2012. Culture and susceptibility results were compiled with information on the age, sex and breed of dog. Repeat submissions were removed. Susceptibility was assessed using results of the Kirby-Bauer disk diffusion method, for a standard panel including amoxicillin-clavulanic acid (AMC), cefovecin (from 2010-2012), cephalothin, clindamycin, enrofloxacin and trimethoprim-sulphonamide (TMS). A total of 5,786 urine samples were submitted for analysis, and 3,135 bacterial isolates were cultured from 2,184 samples. Of these 3,135 isolates, 1,104 (35.2%) were Escherichia coli, 442 (14.1%) were Staphylococcus spp., 357 (11.4%) Proteus mirabilis and 276 (8.8%) were Enterococcus spp. The frequency of culture-positive samples increased with increasing age in both female and male dogs (p<0.001). The percentage of E. coli isolates resistant to AMC and cephalothin increased between 2005 and 2012 (p<0.001), as did resistance to enrofloxacin (p=0.022), but there was no change in resistance to TMS (p=0.696). Enrofloxacin was the antimicrobial with the least resistance shown by the four most common bacteria isolated during the course of the study. The results of this study provide important regional information regarding the prevalence of bacterial uropathogens and their susceptibility patterns. There was an increase in resistance to some commonly used antimicrobials in the treatment of urinary tract infections. Having access to regional antimicrobial susceptibility results is crucial when forming guidelines for the use of antimicrobials for the treatment of urinary tract infections. Given changes in practising habits and antimicrobial usage over time, ongoing monitoring and surveillance of resistance in pathogens is needed.

Prevalence and antimicrobial susceptibility patterns of Shigella among acute diarrheal outpatients in Mekelle hospital, Northern Ethiopia.

PubMed

Gebrekidan, Atsebaha; Dejene, Tsehaye Asmelash; Kahsay, Getahun; Wasihun, Araya Gebreysus

2015-10-28

Emergence of increased antimicrobial resistance of Shigella species is a global challenge, particularly in developing countries where increased misuse of antimicrobial agents occurs. There is no published data in the study area on the prevalence and antimicrobial susceptibility patterns of Shigella among acute diarrheal patients. This study was therefore, under taken to fill this gap. Using cross sectional study method, stool specimens were collected from 216 patients with acute diarrhea at Mekelle Hospital from August to November 2014. Standard bacteriological methods were used to isolate and determine the antimicrobial susceptibility patterns of the isolates, and data were analyzed using SPSS version 20. Out of the total 216 participants, Shigella was isolated from 15 (6.9 %) of the participants. Ten (66.7 %) of the positive isolates were from children <15 years (p = 0.005). Latrine availability, source of drinking water and hand washing habits before meal were statistically significant with shigellosis (p < 0.05). Isolates of Shigella showed 100, 86.7 and 66.7 % resistance to amoxicillin, amoxicillin and cotrimoxazole respectively. Low levels of resistance were observed for norfloxacin and ciprofloxacin (6.7 % each). Overall, 80 % of the isolates showed multidrug resistance. Shigella isolates were highly resistant to amoxicillin, amoxicillin and cotrimoxazole. However, ciprofloxacin and norfloxacin were effective. Antibiotic surveillance is needed to prevent further emergence of drug resistant Shigella strains. More has to be done in the availability of latrine, supply of safe drinking water to the community to reduce the disease burden.

Antimicrobial resistance among Salmonella enterica serovar Infantis from broiler carcasses in Serbia

NASA Astrophysics Data System (ADS)

Nikolić, A.; Baltić, T.; Velebit, B.; Babić, M.; Milojević, L.; Đorđević, V.

2017-09-01

This study aimed to investigate antimicrobial resistance of Salmonella Infantis isolates from poultry carcasses in Serbia. A total of 48 Salmonella isolates were examined for antimicrobial resistance. A panel of 10 antibiotics was selected for testing. Isolates showed resistance to sulfamethoxazole, ceftazidime and cefotaxime (100%). However, the highest number of Salmonella Infantis isolates were sensitive to chloramphenicol. The usage of antibiotics in food producing animals could result in antimicrobial resistance pathogenic bacteria especially Salmonella spp. in poultry, which may be transmitted to humans through the food chain and increase risk of treatment failures.

Effects of combined treatments of irradiation and antimicrobial coatings on reduction of food pathogens in broccoli florets

NASA Astrophysics Data System (ADS)

Takala, P. N.; Salmieri, S.; Vu, K. D.; Lacroix, M.

2011-12-01

The effect of combined treatment of antimicrobial coatings and γ-radiation on reduction of food pathogens such as Listeria monocytogenes, Escherichia coli, and Salmonella Typhimurium was evaluated in broccoli florets. Broccoli florets were inoculated with pathogenic bacteria at 10 6 CFU/g. Inoculated florets were then coated with methylcellulose-based coating containing various mixtures of antimicrobial agents: organic acids (OAs) plus lactic acid bacteria metabolites (LABs), OA plus citrus extract (CE), OA plus CE plus spice mixture (SM), and OA plus rosemary extract (RE). Coated florets were irradiated with various doses (0-3.3 kGy), and microbial analyses were used to calculate the D10 value and radiosensitive relative. The coating containing OA plus CE was the most effective formulation for increasing the sensitization of Escherichia coli by 2.4 times as compared to the control without the antimicrobial coating. For Salmonella Typhimurium, coating containing OA plus LAB was the most effective formulation, increasing radiosensitivity by 2.4 times as well. All antimicrobial coatings had almost the same effect of increasing the sensitivity of Listeria monocytogenes (from 1.31 to 1.45 times) to γ-irradiation.

Prevalence and antimicrobial susceptibility profile of listeria species from ready-to-eat foods of animal origin in Gondar Town, Ethiopia.

PubMed

Garedew, Legesse; Taddese, Ayele; Biru, Tigist; Nigatu, Seleshe; Kebede, Elias; Ejo, Mebrat; Fikru, Abraham; Birhanu, Tamiru

2015-05-12

Listeriosis, mostly caused by Listeria monocytogenes species, has become a major concern to public health authorities due to its clinical severity and high mortality rate, particularly in high risk groups. Currently, there is limited information regarding the prevalence and antimicrobial susceptibility profiles of listeria species in ready-to-eat foods of animal origin in Gondar town, Ethiopia. The aim of this study was to determine the prevalence and antimicrobial susceptibility pattern of Listeria species isolated from ready-to-eat food of animal origin from public dinning places in Gondar town, Ethiopia. A cross sectional study on ready-toeat foods of animal origin sampled from major supermarkets, butcher shops, pastry shops, restaurants and hotels was carried out. Culture, biochemical and sugar tests were conducted for listeria species identification and disc diffusion test was performed to study the antimicrobial susceptibility profiles of the isolates. Out of 384 food samples examined, 96 (25%) were positive for Listeria species. Listeria monocytogenes was detected in 24 (6.25%) of the samples. Listeria monocytogenes was isolated from cake, raw meat, ice cream, minced beef, fish, unpasteurized milk and pizza in that order from higher to lower rate. Assessment of antimicrobial susceptibility profile of L. monocytogenes revealed the presence of four multi-drug resistant isolates. The higher resistance rate was recorded for penicillin, nalidixic acid, tetracycline and chloramphenicol, in decreasing order. All L. monocytogenes identified in the current study were sensitive to amoxicillin, cephalothin, cloxacillin, sulfamethoxazole, gentamicin and vancomycin. The presence of L. monocytogenes including drug resistant and multidrug resistant isolates in some ready-to-eat food items is an indicator of the presence of public health hazards to the consumer, particularly to the high-risk groups. Hence awareness creation on food safety and implementation of regulations about the use of drugs in humans and animals is strongly recommended.

A Review of Ten Years of the Study for Monitoring Antimicrobial Resistance Trends (SMART) from 2002 to 2011.

PubMed

Morrissey, Ian; Hackel, Meredith; Badal, Robert; Bouchillon, Sam; Hawser, Stephen; Biedenbach, Douglas

2013-11-01

Surveillance of antimicrobial agent resistance provides important information to guide microbiologists and infectious disease specialists understanding of the control and the spread of resistance mechanisms within the local environment. Continued monitoring of antimicrobial resistance patterns in the community and in local hospital environments is essential to guide effective empiric therapy. The Study for Monitoring Antimicrobial Resistance Trends (SMART) has monitored the in vitro susceptibility patterns of clinical Gram-negative bacilli to antimicrobial agents collected worldwide from intra-abdominal infections since 2002 and urinary tract infections since 2009. Resistance trends, with a particular focus on carbapenem resistance and the rate of extended-spectrum β-lactamases (ESBLs), were analyzed. Isolates from intra-abdominal infections (n = 92,086) and urinary-tract infections (n = 24,705) were collected and tested using Clinical and Laboratory Standards Institute methods. This review presents carbapenem susceptibility and ESBL rates over ten years of SMART study analysis, including key publications during this period. The SMART study has proved to be a valuable resource in determining pathogen prevalence and antibiotic susceptibility over the last ten years and continues to provide evidence for regulatory susceptibility breakpoints and clinical decision making.

Antimicrobial resistance and prudent drug use for Streptococcus suis.

PubMed

Varela, Norma P; Gadbois, Pierre; Thibault, Claude; Gottschalk, Marcelo; Dick, Paul; Wilson, Jeff

2013-06-01

This paper reviews information on antimicrobial resistance patterns and prudent use of antimicrobials to reduce the impact and spread of resistant Streptococcus suis strains. S. suis is an important pathogen in swine, which can cause significant economic loss. Prudent use of antimicrobials for S. suis is essential to preserve the therapeutic efficacy of broad-spectrum antimicrobials and to minimize selection of resistant S. suis strains. Resistance of S. suis to antimicrobials commonly used in swine, including lincosamides, macrolides, sulphonamides, and tetracycline, has been documented worldwide, with resistance in up to 85% of strains. Among antimicrobials examined, resistance of S. suis has been demonstrated to be relatively low for penicillin (0-27%), ampicillin (0.6-23%), and ceftiofur (0-23%). For penicillin, this result may be due in part to the unique mechanism by which resistance is acquired through modifications in the structure of penicillin-binding proteins. Recommendations to control S. suis infection include focused and careful choice and appropriate use of antimicrobials, together with preventive measures intended to improve swine management.

The antimicrobial activity of fruits from some cultivar varieties of Rubus idaeus and Rubus occidentalis.

PubMed

Krauze-Baranowska, M; Majdan, M; Hałasa, R; Głód, D; Kula, M; Fecka, I; Orzeł, A

2014-10-01

Raspberries, derived from different cultivar varieties, are a popular ingredient of everyday diet, and their biological activity is a point of interest for researchers. The ethanol-water extracts from four varieties of red (Rubus idaeus'Ljulin', 'Veten', 'Poranna Rosa') and black (Rubus occidentalis'Litacz') raspberries were evaluated in the range of their antimicrobial properties as well as phenolic content - sanguiin H-6, free ellagic acid and anthocyanins. The antimicrobial assay was performed with the use of fifteen strains of bacteria, both Gram-negative and Gram-positive. The antimicrobial activity of the extracts varied and depended on the analysed strain of bacteria and cultivar variety, with the exception of Helicobacter pylori, towards which the extracts displayed the same growth inhibiting activity. Two human pathogens Corynebacterium diphtheriae and Moraxella catarrhalis proved to be the most sensitive to raspberry extracts. Contrary to the extracts, sanguiin H-6 and ellagic acid were only active against eight and nine bacterial strains, respectively. The determined MIC and MBC values of both compounds were several times lower than the tested extracts. The highest sensitivity of Corynebacterium diphtheriae to extracts from both black and red raspberries may be due to its sensitivity to sanguiin H-6 and ellagic acid.

A cost-effectiveness analysis of two different antimicrobial stewardship programs.

PubMed

Okumura, Lucas Miyake; Riveros, Bruno Salgado; Gomes-da-Silva, Monica Maria; Veroneze, Izelandia

2016-01-01

There is a lack of formal economic analysis to assess the efficiency of antimicrobial stewardship programs. Herein, we conducted a cost-effectiveness study to assess two different strategies of Antimicrobial Stewardship Programs. A 30-day Markov model was developed to analyze how cost-effective was a Bundled Antimicrobial Stewardship implemented in a university hospital in Brazil. Clinical data derived from a historical cohort that compared two different strategies of antimicrobial stewardship programs and had 30-day mortality as main outcome. Selected costs included: workload, cost of defined daily doses, length of stay, laboratory and imaging resources used to diagnose infections. Data were analyzed by deterministic and probabilistic sensitivity analysis to assess model's robustness, tornado diagram and Cost-Effectiveness Acceptability Curve. Bundled Strategy was more expensive (Cost difference US$ 2119.70), however, it was more efficient (US$ 27,549.15 vs 29,011.46). Deterministic and probabilistic sensitivity analysis suggested that critical variables did not alter final Incremental Cost-Effectiveness Ratio. Bundled Strategy had higher probabilities of being cost-effective, which was endorsed by cost-effectiveness acceptability curve. As health systems claim for efficient technologies, this study conclude that Bundled Antimicrobial Stewardship Program was more cost-effective, which means that stewardship strategies with such characteristics would be of special interest in a societal and clinical perspective. Copyright © 2016 Elsevier Editora Ltda. All rights reserved.

Mode of action and safety of lactosporin, a novel antimicrobial protein produced by Bacillus coagulans ATCC 7050

PubMed Central

Riazi, Shadi; Dover, Sara E.; Chikindas, Michael L.

2012-01-01

Aims To determine the mechanism of action of antimicrobial protein, lactosporin, against Gardnerella vaginalis and to evaluate its safety in-vitro. Methods and Results Bacillus coagulans ATCC 7050 was grown at 37 °C for 18 hours. The cell free supernatant was concentrated 10-fold and screened for antimicrobial activity against indicator strain Micrococcus luteus. The mode of action of lactosporin was determined by measuring the potassium release and monitoring the changes in transmembrane potential (Δψ) and transmembrane pH (ΔpH) of the sensitive cells. Lactosporin caused efflux of potassium ions from M. luteus cells and dissipation of ΔpH in G. vaginalis while it had no effect on the Δψ. The safety of lactosporin was evaluated by using EpiVaginal™ ectocervical (VEC-100) tissue model. Over 80% of the cells in the vaginal tissue remained viable after exposure to lactosporin for 24 hours. Conclusions Lactosporin potentially exerts its antimicrobial activity by selective dissipation of ΔpH and/or by causing leakage of ions from the sensitive cells. Safety studies suggest that lactosporin is a non-cytotoxix antimicrobial for vaginal application. Significance and Impact of the Study This study revealed that lactosporin is an effective and safe antimicrobial preparation with potential application for control of bacterial vaginosis. PMID:22737982

Frequency and antimicrobial susceptibility of aerobic bacterial vaginal isolates.

PubMed

Tariq, Nabia; Jaffery, Tara; Ayub, Rukhsana; Alam, Ali Yawar; Javid, Mahmud Haider; Shafique, Shamsa

2006-03-01

To determine the frequency and antimicrobial susceptibility of aerobic bacterial isolates from high vaginal swab cultures. Cross-sectional survey. Shifa International Hospital, Islamabad, from January 2003 to February 2004. The subjects included 136 symptomatic women attending Obstetrics and Gynecology Out-Patient Department. A proforma was filled to document the demographic details, presenting complaint and examination findings. High vaginal swabs were taken for gram staining, culture and antimicrobial sensitivity testing using standard microbiologic techniques. Normal flora was isolated in 30% of the cases, followed by Candida spp. (21.3%), Enterococcus spp. (14.7%), E.coli (10.2%), Beta hemolytic Streptococcus spp. (7.3%), Staphylococcus spp. (4.4%), Enterobacter spp. (4.4%), while Streptococcus pyogenes, Staphylococcus epidermidis and Klebsiella spp. were isolated 1.5% each. Enterococcus, Staphylococcus and Streptococcus were mostly sensitive to penicillin and amoxicillin while E.coli and Klebsiella were sensitive to (piperacillin-Tazobactum, Imipenem and vancomycin. Enterococci species showed significant resistance to aminoglycoside antibiotics (68.8% to 81.3%) resistance to vancomycin was 5%. Thirty percent of symptomatic patients had normal flora on culture. Candida spp was the most frequent pathogen isolated. Co-amoxiclav should be used as empiric therapy until culture-sensitivity report is available.

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.

Novel mode of action of plant defense peptides: hevein-like antimicrobial peptides from wheat inhibit fungal metalloproteases

USDA-ARS?s Scientific Manuscript database

The multilayered plant immune system relies on rapid recognition of pathogen-associated molecular patterns followed by activation of defense-related genes that results in the reinforcement of plant cell walls and production of antimicrobial compounds. To suppress plant defense, fungi secrete effecto...

Approaches for quantifying antimicrobial consumption per animal species based on national sales data: a Swiss example, 2006 to 2013.

PubMed

Carmo, Luís P; Schüpbach-Regula, Gertraud; Müntener, Cedric; Chevance, Anne; Moulin, Gérard; Magouras, Ioannis

2017-02-09

Antimicrobial use in animals is known to contribute to the global burden of antimicrobial resistance. Therefore, it is critical to monitor antimicrobial sales for livestock and pets. Despite the availability of veterinary antimicrobial sales data in most European countries, surveillance currently lacks consumption monitoring at the animal species level. In this study, alternative methods were investigated for stratifying antimicrobial sales per species using Swiss data (2006-2013). Three approaches were considered: (i) Equal Distribution (ED) allocated antimicrobial sales evenly across all species each product was licensed for; (ii) Biomass Distribution (BMD) stratified antimicrobial consumption, weighting the representativeness of each species' total biomass; and (iii) Longitudinal Study Extrapolation (LSE) assigned antimicrobial sales per species based on a field study describing prescription patterns in Switzerland. LSE is expected to provide the best estimates because it relies on field data. Given the Swiss example, BMD appears to be a reliable method when prescription data are not available, whereas ED seems to underestimate consumption in species with larger populations and higher treatment intensity. These methods represent a valuable tool for improving the monitoring systems of veterinary antimicrobial consumption across Europe. This article is copyright of The Authors, 2017.

Approaches for quantifying antimicrobial consumption per animal species based on national sales data: a Swiss example, 2006 to 2013

PubMed Central

Carmo, Luís P; Schüpbach-Regula, Gertraud; Müntener, Cedric; Chevance, Anne; Moulin, Gérard; Magouras, Ioannis

2017-01-01

Antimicrobial use in animals is known to contribute to the global burden of antimicrobial resistance. Therefore, it is critical to monitor antimicrobial sales for livestock and pets. Despite the availability of veterinary antimicrobial sales data in most European countries, surveillance currently lacks consumption monitoring at the animal species level. In this study, alternative methods were investigated for stratifying antimicrobial sales per species using Swiss data (2006−2013). Three approaches were considered: (i) Equal Distribution (ED) allocated antimicrobial sales evenly across all species each product was licensed for; (ii) Biomass Distribution (BMD) stratified antimicrobial consumption, weighting the representativeness of each species' total biomass; and (iii) Longitudinal Study Extrapolation (LSE) assigned antimicrobial sales per species based on a field study describing prescription patterns in Switzerland. LSE is expected to provide the best estimates because it relies on field data. Given the Swiss example, BMD appears to be a reliable method when prescription data are not available, whereas ED seems to underestimate consumption in species with larger populations and higher treatment intensity. These methods represent a valuable tool for improving the monitoring systems of veterinary antimicrobial consumption across Europe. PMID:28205504

Blood culture gram stain, acridine orange stain and direct sensitivity-based antimicrobial therapy of bloodstream infection in patients with trauma.

PubMed

Behera, B; Mathur, P; Gupta, B

2010-01-01

The purpose of this study was to ascertain if the simple practice of Gram stain, acridine orange stain and direct sensitivity determination of positive blood culture bottles could be used to guide early and appropriate treatment in trauma patients with clinical suspicion of sepsis. The study also aimed to evaluate the error in interpreting antimicrobial sensitivity by direct method when compared to standard method and find out if specific antibiotic-organism combination had more discrepancies. Findings from consecutive episodes of blood stream infection at an Apex Trauma centre over a 12-month period are summarized. A total of 509 consecutive positive blood cultures were subjected to Gram staining. AO staining was done in BacT/ALERT-positive Gram-stain negative blood cultures. Direct sensitivity was performed from 369 blood culture broths, showing single type of growth in Gram and acridine orange staining. Results of direct sensitivity were compared to conventional sensitivity for errors. No 'very major' discrepancy was found in this study. About 5.2 and 1.8% minor error rates were noted in gram-positive and gram-negative bacteria, respectively, while comparing the two methods. Most of the discrepancies in gram-negative bacteria were noted in beta lactam - beta lactamase inhibitor combinations. Direct sensitivity testing was not reliable for reporting of methicillin and vancomycin resistance in Staphylococci. Gram stain result together with direct sensitivity testing is required for optimizing initial antimicrobial therapy in trauma patients with clinical suspicion of sepsis. Gram staining and AO staining proved particularly helpful in the early detection of candidaemia.

Modelling the transmission of healthcare associated infections: a systematic review

PubMed Central

2013-01-01

Background Dynamic transmission models are increasingly being used to improve our understanding of the epidemiology of healthcare-associated infections (HCAI). However, there has been no recent comprehensive review of this emerging field. This paper summarises how mathematical models have informed the field of HCAI and how methods have developed over time. Methods MEDLINE, EMBASE, Scopus, CINAHL plus and Global Health databases were systematically searched for dynamic mathematical models of HCAI transmission and/or the dynamics of antimicrobial resistance in healthcare settings. Results In total, 96 papers met the eligibility criteria. The main research themes considered were evaluation of infection control effectiveness (64%), variability in transmission routes (7%), the impact of movement patterns between healthcare institutes (5%), the development of antimicrobial resistance (3%), and strain competitiveness or co-colonisation with different strains (3%). Methicillin-resistant Staphylococcus aureus was the most commonly modelled HCAI (34%), followed by vancomycin resistant enterococci (16%). Other common HCAIs, e.g. Clostridum difficile, were rarely investigated (3%). Very few models have been published on HCAI from low or middle-income countries. The first HCAI model has looked at antimicrobial resistance in hospital settings using compartmental deterministic approaches. Stochastic models (which include the role of chance in the transmission process) are becoming increasingly common. Model calibration (inference of unknown parameters by fitting models to data) and sensitivity analysis are comparatively uncommon, occurring in 35% and 36% of studies respectively, but their application is increasing. Only 5% of models compared their predictions to external data. Conclusions Transmission models have been used to understand complex systems and to predict the impact of control policies. Methods have generally improved, with an increased use of stochastic models, and more advanced methods for formal model fitting and sensitivity analyses. Insights gained from these models could be broadened to a wider range of pathogens and settings. Improvements in the availability of data and statistical methods could enhance the predictive ability of models. PMID:23809195

Spatial and Temporal Patterns of Biocide Action against Staphylococcus epidermidis Biofilms▿ ‡

PubMed Central

Davison, William M.; Pitts, Betsey; Stewart, Philip S.

2010-01-01

The dynamic antimicrobial action of chlorine, a quaternary ammonium compound, glutaraldehyde, and nisin within biofilm cell clusters of Staphylococcus epidermidis was investigated using time-lapse confocal scanning laser microscopy. The technique allowed for the simultaneous imaging of changes in biofilm structure and disruption of cellular membrane integrity through the loss of an unbound fluorophore loaded into bacterial cells prior to antimicrobial challenge. Each of the four antimicrobial agents produced distinct spatial and temporal patterns of fluorescence loss. The antimicrobial action of chlorine was localized around the periphery of biofilm cell clusters. Chlorine was the only antimicrobial agent that caused any biofilm removal. Treatment with the quaternary ammonium compound caused membrane permeabilization that started at the periphery of cell clusters, then migrated steadily inward. A secondary pattern superimposed on the penetration dynamic suggested a subpopulation of less-susceptible cells. These bacteria lost fluorescence much more slowly than the majority of the population. Nisin caused a rapid and uniform loss of green fluorescence from all parts of the biofilm without any removal of biofilm. Glutaraldehyde caused no biofilm removal and also no loss of membrane integrity. Measurements of biocide penetration and action time at the center of cell clusters yielded 46 min for 10 mg liter−1 chlorine, 21 min for 50 mg liter−1 chlorine, 25 min for the quaternary ammonium compound, and 4 min for nisin. These results underscore the distinction between biofilm removal and killing and reinforce the critical role of biocide reactivity in determining the rate of biofilm penetration. PMID:20457816

Antibacterial potential and genetic profile of Enterococcus faecium strains isolated from human normal flora.

PubMed

Karimaei, Samira; Sadeghi, Javad; Asadian, Mahla; Esghaei, Maryam; Pourshafie, Mohammad Reza; Talebi, Malihe

2016-07-01

Enterococci have a widespread attendance in the circumference and belongs to the enteric commensal microbiota. Most of them produce the antimicrobial compounds and have an inhibition effect on pathogenic microorganisms. The objective of this study was to characterize the enterococcal strains isolated from human normal flora and assess their antibacterial activity. Enterococcal isolates were obtained from the feces of eighteen healthy humans. All enterococcal species were identified by biochemical and species-specific polymerase chain reaction (PCR). These isolates were investigated further to examine their ability to inhibit growth of Salmonella typhi, Shigella flexneri and Escherichia coli by well diffusion assay. Furthermore, antibiotic susceptibility test was performed and genetic relatedness of all isolates was evaluated by Pulse Field Gel Electrophoresis (PFGE). In all, 432 isolates were obtained from fecal samples. All of the isolates identified as Enterococcus faecium by biochemical and molecular (PCR) methods. Using repetitive element palindromic (REP)-PCR method 54 patterns have been obtained and were selected for further evaluation. The results indicated that 66%, 38% and 24% of our isolates had antimicrobial effect against S. typhi, S flexneri and enteroaggregative Escherichia coli (EAEC), respectively. On the other hand, there was no significant inhibition effect against enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC). All isolates were sensitive to vancomycin, teicoplanin, linezolid, ampicillin, chloramphenicol and gentamicin. On the other hand, the resistance rates for erythromycin, tetracycline and ciprofloxacin were 20%, 22%, and 1.8% respectively. In addition, the analysis of PFGE showed forty patterns with eight (40.7%) common types (CT) and thirty two (59.2%) single types (ST). Among eight common types, only one common type (CT5) had similar antimicrobial effect. These results suggested that enterococcal isolates obtained from human normal flora have potential antibacterial effect against S. typhi, S. flexneri and E. coli. Copyright © 2016 Elsevier Ltd. All rights reserved.

AMPA: an automated web server for prediction of protein antimicrobial regions.

PubMed

Torrent, Marc; Di Tommaso, Paolo; Pulido, David; Nogués, M Victòria; Notredame, Cedric; Boix, Ester; Andreu, David

2012-01-01

AMPA is a web application for assessing the antimicrobial domains of proteins, with a focus on the design on new antimicrobial drugs. The application provides fast discovery of antimicrobial patterns in proteins that can be used to develop new peptide-based drugs against pathogens. Results are shown in a user-friendly graphical interface and can be downloaded as raw data for later examination. AMPA is freely available on the web at http://tcoffee.crg.cat/apps/ampa. The source code is also available in the web. marc.torrent@upf.edu; david.andreu@upf.edu Supplementary data are available at Bioinformatics online.

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.

Antioxidant and antimicrobial effects of phenolic compounds extracts of Northeast Portugal honey.

PubMed

Estevinho, Letícia; Pereira, Ana Paula; Moreira, Leandro; Dias, Luís G; Pereira, Ermelinda

2008-12-01

Phenolic compounds of dark and clear honeys from Trás-os-Montes of Portugal were extracted with Amberlite XAD-2 and evaluated for their antioxidant and antimicrobial activities. The antioxidant effect was studied using the in vitro test capacity of scavenge the 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical and of reducing power of iron (III)/ferricyanide complex. The antimicrobial activity was screened using three Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, Staphylococcus lentus) and three Gram-negative bacteria (Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli). The results obtained from the partial identification of honey phenolic compounds by high-performance liquid chromatography with a diode array detector showed that p-hydroxibenzoic acid, cinnamic acid, naringenin, pinocembrin and chrysin are the phenolic compounds present in most of the samples analyzed. Antioxidant potential was dependent of honey extract concentration and the results showed that dark honey phenolic compounds had higher activity than the obtained from clear honey. In the biological assays, results showed that S. aureus were the most sensitive microrganisms and B. subtilis, S. lentus, K. pneumoniae and E. coli were each moderately sensitive to the antimicrobial activity of honey extracts. Nevertheless, no antimicrobial activity was observed in the test with P. aeruginosa.

Gene expression profiling of a nisin-sensitive Listeria monocytogenes Scott A CtsR deletion mutant

USDA-ARS?s Scientific Manuscript database

Listeria monocytogenes is a food-borne pathogen of significant threat to public health. Nisin is the only bacteriocin that can be used as a food preservative. Due to its antimicrobial activity, it can be used to control Listeria monocytogenes in food; however, the antimicrobial mechanism of nisin ...

Inactivation of the sapA to sapF locus of Erwinia chrysanthemi reveals common features in plant and animal bacterial pathogenesis.

PubMed

López-Solanilla, E; García-Olmedo, F; Rodríguez-Palenzuela, P

1998-06-01

We investigated the role in pathogenesis of bacterial resistance to plant antimicrobial peptides. The sapA to sapF (for sensitive to antimicrobial peptides) operon from the pathogenic bacterium Erwinia chrysanthemi has been characterized. It has five open reading frames that are closely related (71% overall amino acid identity) and are in the same order as those of the sapA to sapF operon from Salmonella typhimurium. An E. chrysanthemi sap mutant strain was constructed by marker exchange. This mutant was more sensitive than was the wild type to wheat alpha-thionin and to snakin-1, which is the most abundant antimicrobial peptide from potato tubers. This mutant was also less virulent than was the wild-type strain in potato tubers: lesion area was 37% that of the control, and growth rate was two orders of magnitude lower. These results indicate that the interaction of antimicrobial peptides from the host with the sapA to sapF operon from the pathogen plays a similar role in animal and in plant bacterial pathogenesis.

An investigation of exudative epidermitis (greasy pig disease) and antimicrobial resistance patterns of Staphylococcus hyicus and Staphylococcus aureus isolated from clinical cases

PubMed Central

Park, Jeonghwa; Friendship, Robert M.; Poljak, Zvonimir; Weese, J. Scott; Dewey, Cate E.

2013-01-01

Exudative epidermitis (EE) is a common skin disease of young pigs, caused mainly by Staphylococcus hyicus. Increased prevalence of EE and poor response to treatment are reported. Common strategies used by Ontario pork producers to treat pigs with EE were determined using a survey. Injection of penicillin G was reported as the most common parenteral antibiotic choice. Antimicrobial resistance patterns of S. hyicus and Staphylococcus aureus isolated from clinical cases (30 herds with samples from approximately 6 pigs per farm) showed that 97% of S. hyicus isolates were resistant to penicillin G and ampicillin; 71% of these isolates were resistant to ceftiofur. Similar resistance was noted among S. aureus isolates. Antimicrobial resistance has become a problem in the treatment of EE in Ontario. PMID:23904636

Prevalence of bovine subclinical mastitis, its etiology and diagnosis of antibiotic resistance of dairy farms in four municipalities of a tropical region of Mexico.

PubMed

Olivares-Pérez, Jaime; Kholif, Ahmed Eid; Rojas-Hernández, Saul; Elghandour, Mona Mohamed Mohamed Yasseen; Salem, Abdelfattah Zeidan Mohamed; Bastida, Adrian Zaragoza; Velázquez-Reynoso, David; Cipriano-Salazar, Moisés; Camacho-Díaz, Luis Miguel; Alonso-Fresán, María Uxúa; DiLorenzo, Nicolas

2015-12-01

A region-wide survey was conducted in the tropical area of Tierra Caliente, State of Guerrero, Mexico to estimate the prevalence of subclinical bovine mastitis (SCM), distribution of mastitis pathogens, and in vitro antimicrobial susceptibility of different mastitis pathogens in dairy farms. In total, 1036 quarter milk samples were obtained from 259 cows at 87 different dairy farms. Collected quarter milk samples were submitted for California Mastitis Test (CMT), bacteriological examination, and testing for antimicrobial susceptibility. Overall prevalence of SCM in the studied area was 20.5 %. Prevalence in the different regions was as follows: 28 % in Arcelia municipality, 21 % in Tlalchapa municipality, 19.4 % in Pungarabato municipality, and 14.3 % in Finch Cutzamala municipality. Of all positive isolates, 97.5 % were Gram-negative bacteria. Moreover, of all positive isolates, 37.5 % were Proteus vulgaris, 25 % Salmonella spp., 12.5 % Enterobacter aerogenes, and 10 % Escherichia coli. Klebsiella pneumonia and E. coli were sensitive for netilmicin antimicrobial. However, E. coli was sensitive for pefloxacin and gentamicin with a sensitivity for pefloxacin for E. aerogenes, while Staphylococci were sensitive for gentamicin and dicloxacillin. It could be concluded that practices such as the implementation of mastitis control programs, improved milking hygiene together with an intramammary treatment with netilmicin, pefloxacin, and gentamicin antimicrobials should be considered for mastitis prevention in the study area of Tierra Caliente, in the tropical area of Guerrero, Mexico.

A review on comparative mechanistic studies of antimicrobial peptides against archaea.

PubMed

Varnava, Kyriakos G; Ronimus, Ron S; Sarojini, Vijayalekshmi

2017-11-01

Archaea was until recently considered as a third domain of life in addition to bacteria and eukarya but recent studies support the existence of only two superphyla (bacteria and archaea). The fundamental differences between archaeal, bacterial, and eukaryal cells are probably the main reasons for the comparatively lower susceptibility of archaeal strains to current antimicrobial agents. The possible emerging pathogenicity of archaea and the role of archaeal methanogens in methane emissions, a potent greenhouse gas, has led many researchers to examine the sensitivity patterns of archaea and make attempts to find agents that have significant anti-archaeal activity. Even though antimicrobial peptides (AMPs) are well known with several published reviews concerning their mode of action against bacteria and eukarya, to our knowledge, to date no reviews are available that focus on the action of these peptides against archaea. Herein, we present a review on all the peptides that have been tested against archaea. In addition, in an attempt to shed more light on possible future work that needs to be performed we have included a brief overview of the chemical characteristics, spectrum of activity, and the known mechanism of action of each of these peptides against bacteria and/or fungi. We also discuss the nature of and key physiological differences between Archaea, Bacteria, and Eukarya that are relevant to the development of anti-archaeal peptides. Despite our relatively limited knowledge about archaea, available data suggest that AMPs have an even broader spectrum of activity than currently recognized. © 2017 Wiley Periodicals, Inc.

Phenotypic characteristics and genotypic correlation between Salmonella isolates from a slaughterhouse and retail markets in Yangzhou, China.

PubMed

Cai, Yinqiang; Tao, Jing; Jiao, Yang; Fei, Xiao; Zhou, Le; Wang, Yan; Zheng, Huijuan; Pan, Zhiming; Jiao, Xinan

2016-04-02

An epidemiological investigation of Salmonella spp. in pig and pork samples from one slaughterhouse and its downstream retail markets in Yangzhou, Jiangsu Province, China, was conducted from October 2013 to March 2014. A total of 71.8% (155/216) and 70.9% (78/110), respectively, of the slaughterhouse and retail market samples were recovered positive for Salmonella. All Salmonella isolates were characterized using serotyping, antimicrobial resistance detection, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). Seven serotypes were shared by isolates from the two sources, with the most common serotypes being Salmonella Derby, Typhimurium, and Uganda. Antimicrobial sensitivity testing revealed that the highest antimicrobial resistance rate was against tetracycline (49.7% and 37.2% in isolates from the slaughterhouse and retail market, respectively) with many multidrug-resistant (MDR) isolates in both sources. MLST analysis showed that eight sequence type (ST) patterns were shared, and ST40 occupied an absolute superiority among isolates from both sources. PFGE permitted the resolution of XbaI macrorestriction fragments of the selected 31 Salmonella Derby and 19 Salmonella Typhimurium into 30 and 10 distinct pulsotypes, displaying the high similarity between the isolates from the two sources. Our findings indicated that Salmonella isolates from a slaughterhouse and its downstream retail markets were phenotypically and genetically homologous. Additionally, Salmonella may propagate along the slaughter line and pork production chain from the slaughterhouse to retail markets. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of Antimicrobial Resistance Patterns and Detection of Virulence Genes in Campylobacter Isolates in Italy

PubMed Central

Di Giannatale, Elisabetta; Di Serafino, Gabriella; Zilli, Katiuscia; Alessiani, Alessandra; Sacchini, Lorena; Garofolo, Giuliano; Aprea, Giuseppe; Marotta, Francesca

2014-01-01

Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis) and detection of virulence genes (sequencing and DNA microarray analysis). The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%), tetracycline (55.86%) and nalidixic acid (55.17%). Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations. PMID:24556669

Characterization of antimicrobial resistance patterns and detection of virulence genes in Campylobacter isolates in Italy.

PubMed

Di Giannatale, Elisabetta; Di Serafino, Gabriella; Zilli, Katiuscia; Alessiani, Alessandra; Sacchini, Lorena; Garofolo, Giuliano; Aprea, Giuseppe; Marotta, Francesca

2014-02-19

Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis) and detection of virulence genes (sequencing and DNA microarray analysis). The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%), tetracycline (55.86%) and nalidixic acid (55.17%). Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations.

Microbial Etiology of Pneumonia: Epidemiology, Diagnosis and Resistance Patterns.

PubMed

Cilloniz, Catia; Martin-Loeches, Ignacio; Garcia-Vidal, Carolina; San Jose, Alicia; Torres, Antoni

2016-12-16

Globally, pneumonia is a serious public health concern and a major cause of mortality and morbidity. Despite advances in antimicrobial therapies, microbiological diagnostic tests and prevention measures, pneumonia remains the main cause of death from infectious disease in the world. An important reason for the increased global mortality is the impact of pneumonia on chronic diseases, along with the increasing age of the population and the virulence factors of the causative microorganism. The increasing number of multidrug-resistant bacteria, difficult-to-treat microorganisms, and the emergence of new pathogens are a major problem for clinicians when deciding antimicrobial therapy. A key factor for managing and effectively guiding appropriate antimicrobial therapy is an understanding of the role of the different causative microorganisms in the etiology of pneumonia, since it has been shown that the adequacy of initial antimicrobial therapy is a key factor for prognosis in pneumonia. Furthermore, broad-spectrum antibiotic therapies are sometimes given until microbiological results are available and de-escalation cannot be performed quickly. This review provides an overview of microbial etiology, resistance patterns, epidemiology and microbial diagnosis of pneumonia.

Antianaerobic Antimicrobials: Spectrum and Susceptibility Testing

PubMed Central

Wexler, Hannah M.; Goldstein, Ellie J. C.

2013-01-01

SUMMARY Susceptibility testing of anaerobic bacteria recovered from selected cases can influence the choice of antimicrobial therapy. The Clinical and Laboratory Standards Institute (CLSI) has standardized many laboratory procedures, including anaerobic susceptibility testing (AST), and has published documents for AST. The standardization of testing methods by the CLSI allows comparisons of resistance trends among various laboratories. Susceptibility testing should be performed on organisms recovered from sterile body sites, those that are isolated in pure culture, or those that are clinically important and have variable or unique susceptibility patterns. Organisms that should be considered for individual isolate testing include highly virulent pathogens for which susceptibility cannot be predicted, such as Bacteroides, Prevotella, Fusobacterium, and Clostridium spp.; Bilophila wadsworthia; and Sutterella wadsworthensis. This review describes the current methods for AST in research and reference laboratories. These methods include the use of agar dilution, broth microdilution, Etest, and the spiral gradient endpoint system. The antimicrobials potentially effective against anaerobic bacteria include beta-lactams, combinations of beta-lactams and beta-lactamase inhibitors, metronidazole, chloramphenicol, clindamycin, macrolides, tetracyclines, and fluoroquinolones. The spectrum of efficacy, antimicrobial resistance mechanisms, and resistance patterns against these agents are described. PMID:23824372

'Prevalence and antimicrobial susceptibility of Listeria monocytogenes and methicillin-resistant Staphylococcus aureus strains from raw meat and meat products in Zaria, Nigeria.

PubMed

Ndahi, M D; Kwaga, J K P; Bello, M; Kabir, J; Umoh, V J; Yakubu, S E; Nok, A J

2014-03-01

The bacterial genera Listeria and Staphylococcus have been frequently isolated from food products and are responsible for a number of animal and human diseases. The aim of the study was to simultaneously isolate and characterize L. monocytogenes and Staphylococcus species from 300 samples of raw meat and meat products, to determine the susceptibility of the organisms to commonly used antimicrobial agents and to determine the presence of haemolysin A (hyl) virulence gene in L. monocytogenes and staphylococcal cassette chromosome mecA (SCCmec) gene in the Staph. aureus isolates using PCR. Of the 85 Listeria isolates tested, 12 L. monocytogenes were identified and tested for their sensitivity to 14 antimicrobial agents. All the 12 isolates (100%) were resistant to nine antimicrobial agents, but however sensitive to gentamicin. Only one isolate was found to harbour the hylA gene. Twenty-nine isolates were confirmed as Staph. aureus by the Microbact 12S identification system and were all presumptively identified as methicillin-resistant Staph. aureus species using oxacillin-resistant Staph. aureus basal medium (ORSAB). The 29 Staph. aureus isolates were tested for their sensitivity to 16 antimicrobial agents, and 11 were resistant to methicillin. None of the 11 Staph. aureus isolates harboured the methicillin resistance, mecA gene. Listeria monocytogenes and Staphylococcus aureus are important agents of foodborne diseases. Occurrence of these infectious agents was established in meat and meat products in Zaria, Nigeria. Majority of isolates obtained from this study, displayed multidrug resistance to commonly used antimicrobial agents, including methicillin resistance among the Staph. aureus isolates. The potential virulence of L. monocytogenes found in ready-to-eat food was documented by the carriage of hly A gene by one of the isolates. A different mechanism of methicillin resistance or different homologue of mec A gene may be circulating among Nigerian isolates. © 2013 The Society for Applied Microbiology.

Detection of Group B Streptococcus in Brazilian pregnant women and antimicrobial susceptibility patterns

PubMed Central

Castellano-Filho, Didier Silveira; da Silva, Vânia Lúcia; Nascimento, Thiago César; de Toledo Vieira, Marcel; Diniz, Cláudio Galuppo

2010-01-01

Group B Streptococcus (GBS) is still not routinely screened during pregnancy in Brazil, being prophylaxis and empirical treatment based on identification of risk groups. This study aimed to investigate GBS prevalence in Brazilian pregnant women by culture or polymerase chain reaction (PCR) associated to the enrichment culture, and to determine the antimicrobial susceptibility patterns of isolated bacteria, so as to support public health policies and empirical prophylaxis. After an epidemiological survey, vaginal and anorectal specimens were collected from 221 consenting laboring women. Each sample was submitted to enrichment culture and sheep blood agar was used to isolate suggestive GBS. Alternatively, specific PCR was performed from enrichment cultures. Antimicrobial susceptibility patterns were determined for isolated bacteria by agar diffusion method. No risk groups were identified. Considering the culture-based methodology, GBS was detected in 9.5% of the donors. Twenty five bacterial strains were isolated and identified. Through the culture-PCR methodology, GBS was detected in 32.6% specimens. Bacterial resistance was not detected against ampicillin, cephazolin, vancomycin and ciprofloxacin, whereas 22.7% were resistant to erythromycin and 50% were resistant to clindamycin. GBS detection may be improved by the association of PCR and enrichment culture. Considering that colony selection in agar plates may be laboring and technician-dependent, it may not reflect the real prevalence of streptococci. As in Brazil prevention strategies to reduce the GBS associated diseases have not been adopted, prospective studies are needed to anchor public health policies especially considering the regional GBS antimicrobial susceptibility patterns. PMID:24031585

Factors associated with antimicrobial use in nursing homes: a multilevel model.

PubMed

Benoit, Stephen R; Nsa, Wato; Richards, Chesley L; Bratzler, Dale W; Shefer, Abigail M; Steele, Lynn M; Jernigan, John A

2008-11-01

To describe antimicrobial prescribing patterns in nursing homes. Retrospective, observational study. Total of 73 nursing homes in four U.S. states; study period was from September 1, 2001, through February 28, 2002. Four thousand seven hundred eighty nursing home residents. Number and type of antimicrobials, indication for their use, and resident and facility factors associated with antimicrobial use in nursing homes. Of 4,780 residents, 2,017 (42%) received one or more antibiotic courses. Overall, residents received a mean of 4.8 courses/1,000 resident-days (mean facility range 0.4-23.5). In multivariable analysis, higher probability of nursing home discharge and of being categorized in the rehabilitation, extensive services, special care, or clinically complex Resource Utilization Groups were associated with higher rates of antimicrobial usage. Three drug classes accounted for nearly 60% of antimicrobial courses-fluoroquinolones (38%), first-generation cephalosporins (11%), and macrolides (10%). The most common conditions for which antimicrobials were prescribed were respiratory tract (33%) and urinary tract (32%) infections. Antibiotic use is variable in nursing homes. Targeting educational and other antimicrobial use interventions to the treatment of certain clinical diagnoses and conditions may be an appropriate strategy for optimizing antimicrobial use in this setting.

Prevalence, molecular and antimicrobial resistance of Salmonella isolated from sausages in Meknes, Morocco.

PubMed

Ed-Dra, Abdelaziz; Filali, Fouzia Rhazi; Karraouan, Bouchra; El Allaoui, Abdellah; Aboulkacem, Amal; Bouchrif, Brahim

2017-04-01

Salmonella is among the most important food borne pathogens worldwide contaminating a wide range of animal products including meat products. The aims of this study go through two steps: The first step is to estimate the proportion of sausages products contaminated with Salmonella in Meknes city (Morocco), which were collected from various shopping sites: butchery, street vendors, supermarket and souk (Weekly market combines the population of the small villages around Meknes city). The second one is to identify serovars, to determine the antimicrobials resistance patterns of isolates and to detect the invA and spvC genes. 34 (21.79%) Salmonella were isolated, recovered 4 serogroups and 12 serotypes. The most prevalent serotypes were Salmonella Corvallis (23.53%) and Salmonella Kentucky (17.65%). All Salmonella isolates were tested for their susceptibility to 18 selected antimicrobials agents, of which 100% were resistant to at least one antimicrobial, 85.30% (29/34) were resistant to two or more antimicrobials and 44.12% (15/34) were resistant to at least three antimicrobials. All Salmonella are resistant to ampicillin, 76.47% to streptomycin, 20.59% to sulfonamides, 17.65% to Tetracycline and 11.77% to Ofloxacin. The "ACSSuT" penta-resistance pattern was observed in tow of the Salmonella Typhimurium strains. In addition, this study showed that all Salmonella strains (34) were positive for invasion gene invA and negative for the virulence gene spvC. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multicenter Study of Antimicrobial Susceptibility of Anaerobic Bacteria in Korea in 2012

PubMed Central

Lee, Yangsoon; Park, Yeon-Joon; Kim, Mi-Na; Uh, Young; Kim, Myung Sook

2015-01-01

Background Periodic monitoring of regional or institutional resistance trends of clinically important anaerobic bacteria is recommended, because the resistance of anaerobic pathogens to antimicrobial drugs and inappropriate therapy are associated with poor clinical outcomes. There has been no multicenter study of clinical anaerobic isolates in Korea. We aimed to determine the antimicrobial resistance patterns of clinically important anaerobes at multiple centers in Korea. Methods A total of 268 non-duplicated clinical isolates of anaerobic bacteria were collected from four large medical centers in Korea in 2012. Antimicrobial susceptibility was tested by the agar dilution method according to the CLSI guidelines. The following antimicrobials were tested: piperacillin, piperacillin-tazobactam, cefoxitin, cefotetan, imipenem, meropenem, clindamycin, moxifloxacin, chloramphenicol, metronidazole, and tigecycline. Results Organisms of the Bacteroides fragilis group were highly susceptible to piperacillin-tazobactam, imipenem, and meropenem, as their resistance rates to these three antimicrobials were lower than 6%. For B. fragilis group isolates and anaerobic gram-positive cocci, the resistance rates to moxifloxacin were 12-25% and 11-13%, respectively. Among B. fragilis group organisms, the resistance rates to tigecycline were 16-17%. Two isolates of Finegoldia magna were non-susceptible to chloramphenicol (minimum inhibitory concentrations of 16-32 mg/L). Resistance patterns were different among the different hospitals. Conclusions Piperacillin-tazobactam, cefoxitin, and carbapemems are highly active β-lactam agents against most of the anaerobes. The resistance rates to moxifloxacin and tigecycline are slightly higher than those in the previous study. PMID:26206683

In vitro sensitivities to antimicrobial drugs of ureaplasmas isolated from the bovine respiratory tract, genital tract and eye.

PubMed

Kishima, M; Hashimoto, K

1979-09-01

The sensitivity to 18 antimicrobial drugs was examined for 66 strains of Ureaplasma sp isolated from respiratory tracts of calves suffering from enzootic pneumonia, urinary tracts of bulls and eyes of cows suffering from infectious bovine kerato-conjunctivitis. Furamizole, tiamulin fumarate, erythromycin lactobionate, malidomycin C, doxycycline hydrochloride, kitasamycin tartrate, tylosin tartrate, T-2636C, tetracycline hydrochloride, oxytetracycline hydrochloride, chlortetracycline hydrochloride, oleandomycin phosphate, furazolidone, spiramycin adipate, chloramphenicol and thiophenicol showed strong inhibiting activity on all the test strains. Among them, furamizole, tiamulin fumarate and erythromycin lactobionate were most active. Kanamycin sulphate showed weak activity on all the strains tested. The differences in origin of the test strains did not affect their sensitivity to any of the drugs.

A simple and low-cost platform technology for producing pexiganan antimicrobial peptide in E. coli.

PubMed

Zhao, Chun-Xia; Dwyer, Mirjana Dimitrijev; Yu, Alice Lei; Wu, Yang; Fang, Sheng; Middelberg, Anton P J

2015-05-01

Antimicrobial peptides, as a new class of antibiotics, have generated tremendous interest as potential alternatives to classical antibiotics. However, the large-scale production of antimicrobial peptides remains a significant challenge. This paper reports a simple and low-cost chromatography-free platform technology for producing antimicrobial peptides in Escherichia coli (E. coli). A fusion protein comprising a variant of the helical biosurfactant protein DAMP4 and the known antimicrobial peptide pexiganan is designed by joining the two polypeptides, at the DNA level, via an acid-sensitive cleavage site. The resulting DAMP4(var)-pexiganan fusion protein expresses at high level and solubility in recombinant E. coli, and a simple heat-purification method was applied to disrupt cells and deliver high-purity DAMP4(var)-pexiganan protein. Simple acid cleavage successfully separated the DAMP4 variant protein and the antimicrobial peptide. Antimicrobial activity tests confirmed that the bio-produced antimicrobial peptide has the same antimicrobial activity as the equivalent product made by conventional chemical peptide synthesis. This simple and low-cost platform technology can be easily adapted to produce other valuable peptide products, and opens a new manufacturing approach for producing antimicrobial peptides at large scale using the tools and approaches of biochemical engineering. © 2014 Wiley Periodicals, Inc.

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.

The detection and antimicrobial susceptibility profile of Shigella isolates from meat and swab samples at butchers' shops in Gondar town, Northwest Ethiopia.

PubMed

Garedew, Legesse; Hagos, Zenabu; Zegeye, Bidir; Addis, Zelalem

2016-01-01

Food borne pathogens are major causes of deaths, illnesses and billions of dollars of expenses. The burden of food borne illness is worsened by the ever increasing rate of antimicrobial resistance microbes. Shigella, a bacterial pathogen associated with food, is reported to account for higher prevalence rates of food borne illness in different settings. A cross-sectional study was conducted from February 10 to June 30, 2013, at the butcher houses of Gondar town in the Northwest of Ethiopia to assess the prevalence and antimicrobial susceptibility pattern of Shigella. Cattle raw meat and swab samples from selected critical control points, including knives, chopping boards, and the hands and noses of butchers, were collected and analyzed. The identification of Shigella was carried out using colony characteristics, the Gram reaction, and biochemical tests. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disc diffusion method. The overall hygienic status of the butcher shops was also assessed using a checklist. An observational analysis revealed that the sanitary condition of the butcher shops and their premises was poor. Of 306 samples screened, 10.5% were positive for Shigella. Approximately 7.4% of meat samples and 10.2% of swab samples were contaminated with Shigella. Out of the total Shigella isolates, 90.6%, 46.9%, 18.8% and 9.4% were resistant to ampicillin, amoxicillin, ceftriaxone and tetracycline, respectively. A multidrug resistance pattern was recorded in 27.8% of the isolates. In conclusion, the safety of meat sold at Gondar butchers houses was poor. The identified Shigella isolates showed high levels of drug resistance and multidrug resistance patterns for commonly used antimicrobials in veterinary and human medicine. Practicing wise use of antimicrobials and strict sanitary interventions at different critical control points is strongly recommended, in addition to further in-depth studies to prevent unprecedented consequences from shigellosis. Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Differences in the antimicrobial susceptibility profiles of Moraxella bovis, M. bovoculi and M. ovis

PubMed Central

Maboni, Grazieli; Gressler, Leticia T.; Espindola, Julia P.; Schwab, Marcelo; Tasca, Caiane; Potter, Luciana; de Vargas, Agueda Castagna

2015-01-01

The aim of this study was to determine the differences in the antimicrobial susceptibility profiles of Moraxella bovis, M. bovoculi and M. ovis. Thirty-two strains of Moraxella spp. isolated from cattle and sheep with infectious keratoconjunctivitis were tested via broth microdilution method to determine their susceptibility to ampicillin, cefoperazone, ceftiofur, cloxacillin, enrofloxacin, florfenicol, gentamicin, neomycin, oxytetracycline and penicillin. The results demonstrated that Moraxella spp. strains could be considered sensitive for most of the antimicrobials tested in this study, but differences between the antimicrobial susceptibility profiles of these three Moraxella species were found. M. bovis might differ from other species due to the higher MIC and MBC values it presented. PMID:26273272

Resistance profiles to antimicrobial agents in bacteria isolated from acute endodontic infections: systematic review and meta-analysis.

PubMed

Lang, Pauline M; Jacinto, Rogério C; Dal Pizzol, Tatiane S; Ferreira, Maria Beatriz C; Montagner, Francisco

2016-11-01

Infected root canal or acute apical abscess exudates can harbour several species, including Fusobacterium, Porphyromonas, Prevotella, Parvimonas, Streptococcus, Treponema, Olsenella and not-yet cultivable species. A systematic review and meta-analysis was performed to assess resistance rates to antimicrobial agents in clinical studies that isolated bacteria from acute endodontic infections. Electronic databases and the grey literature were searched up to May 2015. Clinical studies in humans evaluating the antimicrobial resistance of primary acute endodontic infection isolates were included. PRISMA guidelines were followed. A random-effect meta-analysis was employed. The outcome was described as the pooled resistance rates for each antimicrobial agent. Heterogeneity and sensitivity analyses were performed. Subgroup analyses were conducted based upon report or not of the use of antibiotics prior to sampling as an exclusion factor (subgroups A and B, respectively). Data from seven studies were extracted. Resistance rates for 15 different antimicrobial agents were evaluated (range, 3.5-40.0%). Lower resistance rates were observed for amoxicillin/clavulanic acid and amoxicillin; higher resistance rates were detected for tetracycline. Resistance rates varied according to previous use of an antimicrobial agent as demonstrated by the subgroup analyses. Heterogeneity was observed for the resistance profiles of penicillin G in subgroup A and for amoxicillin, clindamycin, metronidazole and tetracycline in subgroup B. Sensitivity analyses demonstrated that resistance rates changed for metronidazole, clindamycin, tetracycline and amoxicillin. These findings suggest that clinical isolates had low resistance to β-lactams. Further well-designed studies are needed to clarify whether the differences in susceptibility among the antimicrobial agents may influence clinical responses to treatment. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Antimicrobial Stewardship in the Emergency Department: Challenges, Opportunities, and a Call to Action for Pharmacists.

PubMed

Bishop, Bryan M

2016-12-01

Antimicrobial resistance is a national public health concern. Misuse of antimicrobials for conditions such as upper respiratory infection, urinary tract infections, and cellulitis has led to increased resistance to antimicrobials commonly utilized to treat those infections, such as sulfamethoxazole/trimethoprim and flouroquinolones. The emergency department (ED) is a site where these infections are commonly encountered both in ambulatory patients and in patients requiring admission to a hospital. The ED is uniquely positioned to affect the antimicrobial use and resistance patterns in both ambulatory settings and inpatient settings. However, implementing antimicrobial stewardship programs in the ED is fraught with challenges including diagnostic uncertainty, distractions secondary to patient or clinician turnover, and concerns with patient satisfaction to name just a few. However, this review article highlights successful interventions that have stemmed inappropriate antimicrobial use in the ED setting and warrant further study. This article also proposes other, yet to be validated proposals. Finally, this article serves as a call to action for pharmacists working in antimicrobial stewardship programs and in emergency medicine settings. There needs to be further research on the implementation of these and other interventions to reduce inappropriate antimicrobial use to prevent patient harm and curb the development of antimicrobial resistance. © The Author(s) 2015.

Prevalence of clarithromycin-resistant Helicobacter pylori strains in gastric mucosa-associated lymphoid tissue lymphoma patients.

PubMed

Bilgilier, Ceren; Simonitsch-Klupp, Ingrid; Kiesewetter, Barbara; Raderer, Markus; Dolak, Werner; Makristathis, Athanasios; Steininger, Christoph

2016-06-01

Gastric MALT lymphoma is closely associated with Helicobacter pylori infection. Bacterial eradication therapy comprising clarithromycin is the first-line treatment in gastric MALT lymphoma patients. However, antimicrobial resistance to clarithromycin has been increasing in Europe, and thus far, it has not been examined in gastric MALT lymphoma patients. Based upon histopathological investigation, 17 adult gastric MALT lymphoma patients were identified to be related with H. pylori infection between 1997 and 2014. Detection of H. pylori infection in these patients and clarithromycin susceptibility testing were performed by 23S rRNA gene real-time PCR. Twelve of the patients were confirmed with H. pylori infection by real-time PCR. Among these patients, only two were found to be infected with clarithromycin-resistant H. pylori strain. In one of them, both the clarithromycin-resistant and sensitive genotype were detected. The rate of clarithromycin resistance was 15.4 %. Clarithromycin resistance pattern in gastric MALT lymphoma patients is under the predictions since a previous study performed in Central Europe revealed a rate of 36.6 % in Austria. Considering the low antimicrobial resistance rate, clarithromycin is still an option in gastric MALT lymphoma management.

Urinary tract infection in pregnant population, which empirical antimicrobial agent should be specified in each of the three trimesters?

PubMed

Unlu, Bekir Serdar; Yildiz, Yunus; Keles, Ibrahim; Kaba, Metin; Kara, Halil; Tasin, Cuma; Erkilinc, Selcuk; Yildirim, Gulcin

2014-05-01

We aimed to investigate the bacterial profile and the adequacy of antimicrobial treatment in pregnant women with urinary tract infection. This retrospective observational study was conducted with 753 pregnant women who needed hospitalization because of UTI in each of the three trimesters. Midstream urine culture and antimicrobial susceptibility tests were evaluated. E. Coli was the most frequently isolated bacterial agent (82.2%), followed by Klebsiella spp. (11.2%). In each of the three trimesters, E. Coli remained the most frequently isolated bacterium (86%, 82.2%, 79.5%, respectively), followed by Klebsiella spp. (9%, 11.6%, 12.2%, respectively). Enterococcus spp. were isolated as a third microbial agent, with 43 patients (5.7%) in the three trimesters. The bacteria were found to be highly sensitive to fosfomycin, with 98-99% sensitivity for E.Coli and 88-89% for Klebsiella spp. and for Enterococcus spp. 93-100% nitrofurantoin sensitivity for each of the three trimesters. We demonstrated that E. Coli and Klebsiella spp. are the most common bacterial agents isolated from urine culture of pregnant women with UTI in each of the three trimesters. We consider fosfomycin to be the most adequate first-line treatment regimen due to high sensitivity to the drug, ease of use and safety for use in pregnancy

New Approaches to Antibiotic Use and Review of Recently Approved Antimicrobial Agents.

PubMed

Hahn, Andrew W; Jain, Rupali; Spach, David H

2016-07-01

Antimicrobial drug-resistance continues to force adaptation in our clinical practice. We explore new evidence regarding adjunctive antibiotic therapy for skin and soft tissue abscesses as well as duration of therapy for intra-abdominal abscesses. As new evidence refines optimal practice, it is essential to support clinicians in adopting practice patterns concordant with evidence-based guidelines. We review a simple approach that can 'nudge' clinicians towards concordant practices. Finally, the use of novel antimicrobials will play an increasingly important role in contemporary therapy. We review five new antimicrobials recently FDA-approved for use in drug-resistant infections: dalbavancin, oritavancin, ceftaroline, ceftolozane-tazobactam, and ceftazidime-avibactam. Copyright © 2016 Elsevier Inc. All rights reserved.

Phytotherapy as an alternative to conventional antimicrobials: combating microbial resistance.

PubMed

Enioutina, Elena Yu; Teng, Lida; Fateeva, Tatyana V; Brown, Jessica C S; Job, Kathleen M; Bortnikova, Valentina V; Krepkova, Lubov V; Gubarev, Michael I; Sherwin, Catherine M T

2017-11-01

In the modern antimicrobial era, the rapid spread of resistance to antibiotics and introduction of new and mutating viruses is a global concern. Combating antimicrobial resistant microbes (AMR) requires coordinated international efforts that incorporate new conventional antibiotic development as well as development of alternative drugs with antimicrobial activity, management of existing antimicrobials, and rapid detection of AMR pathogens. Areas covered: This manuscript discusses some conventional strategies to control microbial resistance. The main purpose of the manuscript is to present information on specific herbal medicines that may serve as good treatment alternatives to conventional antimicrobials for infections sensitive to conventional as well as resistant strains of microorganisms. Expert commentary: Identification of potential new antimicrobials is challenging; however, one source for potential structurally diverse and complex antimicrobials are natural products. Natural products may have advantages over other post-germ theory antimicrobials. Many antimicrobial herbal medicines possess simultaneous antibacterial, antifungal, antiprotozoal and/or antiviral properties. Herbal products have the potential to boost host resistance to infections, particularly in immunocompromised patients. Antimicrobial broad-spectrum activity in conjunction with immunostimulatory properties may help to prevent microbial resistance to herbal medicine. As part of the efforts to broaden use of herbal medicines to treat microbial infections, pre-clinical and clinical testing guidelines of these compounds as a whole should be implemented to ensure consistency in formulation, efficacy and safety.

Prevalence of antimicrobial drug resistant bacteria carried by in- and outpatients attending a secondary care hospital in Zambia.

PubMed

Nagelkerke, Marjolijn M B; Sikwewa, Kapembwa; Makowa, Dennis; de Vries, Irene; Chisi, Simon; Dorigo-Zetsma, J Wendelien

2017-08-10

Antimicrobial resistance is an increasing global health problem. Very little data on resistance patterns of pathogenic bacteria in low-income countries exist. The aim of this study was to measure the prevalence of antimicrobial drug resistant bacteria carried by in- and outpatients in the resource constraint setting of a secondary care hospital in Zambia. Nasal and rectal samples from 50 in- and 50 outpatients were collected. Patients were randomly selected and informed consent was obtained. Nasal samples were tested for the presence of methicillin-resistant Staphylococcus aureus (MRSA), and rectal samples for Gram-negative rods (family of Enterobacteriaceae) non-susceptible to gentamicin, ciprofloxacin and ceftriaxone. Additionally, E-tests were performed on ceftriaxone-resistant Enterobacteriaceae to detect extended-spectrum β-lactamases (ESBLs). 14% of inpatients carried S. aureus, and 18% of outpatients. No MRSA was found. 90% of inpatients and 48% of outpatients carried one or more Enterobacteriaceae strains (75% Escherichia coli and Klebsiella pneumonia) resistant to gentamicin, ciprofloxacin and/or ceftriaxone (p < 0.001). Among inpatients gentamicin resistance was most prevalent (in 78%), whereas among outpatients ciprofloxacin resistance prevailed (in 38%). All ceftriaxone-resistant Enterobacteriaceae were ESBL-positive; these were present in 52% of inpatients versus 12% of outpatients (p < 0.001). We conclude it is feasible to perform basic microbiological procedures in the hospital laboratory in a low-income country and generate data on antimicrobial susceptibility. The high prevalence of antimicrobial drug resistant Enterobacteriaceae carried by in- and outpatients is worrisome. In order to slow down antimicrobial resistance, surveillance data on local susceptibility patterns of bacteria are a prerequisite to generate guidelines for antimicrobial therapy, to guide in individual patient treatment and to support implementation of infection control measures in a hospital.

Antimicrobial Susceptibility Patterns of Clostridium difficile Isolates from Family Dairy Farms.

PubMed

Bandelj, P; Golob, M; Ocepek, M; Zdovc, I; Vengust, M

2017-05-01

A significant risk factor for developing Clostridium difficile infection (CDI) in humans and animals is associated with the antimicrobial use. It has often been hypothesized that farm animals could be the source for human infection with Clostridium difficile (CD). In the European Union, family-run dairy farms are the predominant farming model, which are more interlinked within the community compared to large-scale intensive dairy or beef farms. Therefore, it is important to investigate antimicrobial susceptibility patterns of CD in such environment. A total of 159 CD isolates from 20 family dairy farms were tested with a customized broth microdilution plate for their antimicrobial resistance. Seventeen antimicrobials were selected (amoxicillin, ceftriaxone, clindamycin, daptomycin, erythromycin, fusidic acid, imipenem, levofloxacin, linezolid, metronidazole, moxifloxacin, oxacillin, rifampicin, tetracycline, tigecycline, trimethoprim/sulfamethoxazole and vancomycin), which are commonly used for treatment of CDI in veterinary and human medicine, or were previously applied in CD epidemiological studies. Antimicrobials, which are used for treatment of CDI in humans (metronidazole, vancomycin, fusidic acid, tigecycline, linezolid) inhibited CD growth in vitro. Most CD isolates were resistant to erythromycin (93.1%), daptomycin (69.2%) and clindamycin (46.5%). High multiple-resistance was found in CD ribotype 012 (n = 5, 100%), some CD SLO 060 (n = 4, 25%) and one CD 033 (n = 1, 1.1%). High multiple-resistance in this study was linked with CD ribotypes and not with the origin of CD. The low prevalence of these ribotypes (6.3%; 10/159) indicates that family-run dairy farms are an unlikely source of CD with multiple-resistance to antimicrobials. © 2016 Blackwell Verlag GmbH.

Molecular detection of six virulence genes in Pseudomonas aeruginosa isolates detected in children with urinary tract infection.

PubMed

Badamchi, Ali; Masoumi, Hossein; Javadinia, Shima; Asgarian, Ramin; Tabatabaee, Azardokht

2017-06-01

Although a vast majority of Urinary tract infections (UTIs) are caused by E. coli, epidemiological reports have indicated an increasing rate of such infections caused by some other opportunistic organisms including Pseudomonas aeruginosa. Antimicrobial susceptibility and pathogenesis mechanisms of P. aeruginosa are poorly understood. The aim of this study was to detect some virulence factor genes and antimicrobial susceptibility patterns of P. aeruginosa isolates detected in patients with UTI, in children hospital of Tehran, Tehran, Iran. Eighty-four Pseudomonas aeruginosa were isolated. Then, the presence of six virulence genes, in the genome of the isolates was evaluated using PCR amplifications techniques. Finally, antimicrobial susceptibility pattern of the isolates was determined by disk diffusion method. According to the results, lasB was the most prevalent virulence gene that could be detected in the P. aeruginosa isolates (92.9%) used in this study. This was followed by aprA (81.2%), toxA (69.4%), and algD (60%) genes. Two genes, plcH and plcN, were detected in about 38.8% of the isolates. Additionally, Imipenem was found as the most active agent against the P. aeruginosa isolates used in this research. However, Cefotaxime resistance was observed in most of the isolates. Our P. aeruginosa isolates exhibited a great degree of heterogeneity not only in their virulence genes but also in their antimicrobial susceptibility profiles. Imipenem therapies tend to be among the best choices in the management of UTI caused by P. aeruginosa. As a conclusion, assessment of antimicrobial susceptibility pattern and also analyzing the virulence factors can be highly helpful to develop effective treatment strategies against P. aeruginosa urinary infections. Copyright © 2017. Published by Elsevier Ltd.

Strain Types and Antimicrobial Resistance Patterns of Clostridium difficile Isolates from the United States, 2011 to 2013

PubMed Central

Goering, Richard V.; Whitmore, Joseph D.; Lynn, Ashley N. W.; Persing, David H.; Tenover, Fred C.

2014-01-01

We determined the PCR ribotypes and antimicrobial susceptibility patterns of 508 toxigenic Clostridium difficile isolates collected between 2011 and 2013 from 32 U.S. hospitals. Of the 29 PCR ribotypes identified, the 027 strain type was the most common (28.1%), although the rates varied by geographic region. Ribotype 014/020 isolates appear to be emerging. Clindamycin and moxifloxacin resistances (36.8% and 35.8%, respectively) were the most frequent resistance phenotypes observed. Reduced susceptibility to vancomycin was observed in 39.1% of 027 isolates. PMID:24752264

Antimicrobial susceptibility pattern of Brachyspira intermedia isolates from European layers.

PubMed

Verlinden, Marc; Boyen, Filip; Pasmans, Frank; Garmyn, An; Haesebrouck, Freddy; Martel, An

2011-09-01

A broth microdilution method was used to determine the antimicrobial susceptibility of 20 Brachyspira intermedia isolates obtained from different layer flocks in Belgium and The Netherlands between 2008 and 2010. The antimicrobial agents used were tylosin, tilmicosin, tiamulin, valnemulin, doxycycline, and lincomycin. The minimal inhibitory concentration (MIC) distribution patterns of tylosin, tilmicosin, lincomycin, and doxycycline were bimodal, demonstrating acquired resistance against doxycycline in three strains, against the macrolides in two strains, and against lincomycin in one strain. The MICs of tiamulin and valnemulin showed a monomodal distribution, but with tailing toward the higher MIC values, possibly suggesting low-level acquired resistance in six isolates. Sequencing revealed a G1058C mutation in the 16S rRNA gene in all doxycycline-resistant strains. The strain resistant to tylosin, tilmicosin, and lincomycin had an A2058T mutation in the 23S rRNA gene.

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.

Characterization of in vitro phenotypes of Burkholderia pseudomallei and Burkholderia mallei strains potentially associated with persistent infection in mice.

PubMed

Bernhards, R C; Cote, C K; Amemiya, K; Waag, D M; Klimko, C P; Worsham, P L; Welkos, S L

2017-03-01

Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm), the agents of melioidosis and glanders, respectively, are Tier 1 biothreats. They infect humans and animals, causing disease ranging from acute and fatal to protracted and chronic. Chronic infections are especially challenging to treat, and the identification of in vitro phenotypic markers which signal progression from acute to persistent infection would be extremely valuable. First, a phenotyping strategy was developed employing colony morphotyping, chemical sensitivity testing, macrophage infection, and lipopolysaccharide fingerprint analyses to distinguish Burkholderia strains. Then mouse spleen isolates collected 3-180 days after infection were characterized phenotypically. Isolates from long-term infections often exhibited increased colony morphology differences and altered patterns of antimicrobial sensitivity and macrophage infection. Some of the Bp and Bm persistent infection isolates clearly displayed enhanced virulence in mice. Future studies will evaluate the potential role and significance of these phenotypic markers in signaling the establishment of a chronic infection.

The farm cost of decreasing antimicrobial use in dairy production

PubMed Central

Tauer, Loren William; Gröhn, Yrjo Tapio

2018-01-01

Antimicrobials are used in animal agriculture to cure bacterial infectious diseases. However, antimicrobial use (AMU) inevitably leads to the selection of resistant bacteria, potentially infecting humans. As a global public threat, antimicrobial resistance has led policy makers to implement regulations supervising AMU. The objective of our research was to investigate the farm impact of several potential policies aimed at decreasing AMU. We modeled a dairy herd of 1000 cows with an average level of disease prevalence for the nine most frequent bacterial dairy diseases found in western countries. We calculated the farm net costs of AMU prohibition, as well as cost increases in antimicrobial treatments prices, and an increase in the milk withdrawal period after AMU. Sensitivity analyses were conducted to assess the impact of output and input prices, and disease prevalence. At a mean disease prevalence, the average net costs of not using antimicrobials were $61 per cow per year greater compared to a scenario modeling current farm AMU. The model predicted that the minimum and maximum increased costs associated with AMU prohibition were $46 and $73 per cow per year compared to current AMU. In each scenario, the cost difference increased with disease prevalence. Sensitivity analysis showed that the three stochastic variables which most significantly influenced the cost difference were respectively, cow replacement prices, cow slaughter price, and the milk price. Antimicrobial price increases of a factor of five, or extending the milk withdrawal period by 15 days, resulted in increasing the costs of diseases to a level where the farmer was better off not using antimicrobials. Our results suggest that the farm level costs of AMU prohibition in many cases might be minor, although the consequences of any policy instrument should be carefully evaluated to reach the ultimate goal of decreasing AMU without threatening the sustainability of milk production. PMID:29566103

In vitro Antimicrobial Activity of Traditional Plant Used in Mestizo Shamanism from the Peruvian Amazon in Case of Infectious Diseases

PubMed Central

Roumy, Vincent; Gutierrez-Choquevilca, Andréa-Luz; Lopez Mesia, Jean Pierre; Ruiz, Lastenia; Ruiz Macedo, Juan Celidonio; Abedini, Amin; Landoulsi, Ameni; Samaillie, Jennifer; Hennebelle, Thierry; Rivière, Céline; Neut, Christel

2015-01-01

Context: Our survey was performed near Iquitos (Peruvian Amazon) and its surroundings and leads us to consider Mestizo ethnomedical practices. The plant species reported here are traditionally used for ailments related to microbial infections. Inhabitants of various ethnic origins were interviewed, and 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi-resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto (Peru). Material and Method: The minimum inhibitory concentrations (MICs) of the plant crude extracts were carried out using the agar dilution method and ranged between 0.075 and 5.0 mg/ml. Results: Of the 40 plants analyzed, 9 species showed MIC ≤0.3 mg/ml (Anacardium occidentale, Couroupita guianensis, Croton lechleri, Davilla rugosa, Erythrina amazonica, Jacaranda copaia subsp. Spectabilis, Oenocarpus bataua, Peperomia macrostachya, and Phyllanthus urinaria) for one or several of the 36 microorganisms and only 6 drug extracts were inactive. Among the 40 plants, 13 were evaluated for the first time for an antibacterial activity. Conclusion: This evaluation of the antimicrobial activity of 40 plants using an approved standard methodology allowed comparing those activities against various microbes to establish antimicrobial spectra of standardized plant extracts, and give support to the traditional use of these plants. It may also help discovering new chemical classes of antimicrobial agents that could serve against multi-resistant bacteria. SUMMARY This study leads us to consider Mestizo ethnomedical practices near Iquitos (Peruvian Amazon) and its surroundings. The plant species reported here are traditionally used for ailments related to microbial infections. 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto. PMID:27013805

In vitro Antimicrobial Activity of Traditional Plant Used in Mestizo Shamanism from the Peruvian Amazon in Case of Infectious Diseases.

PubMed

Roumy, Vincent; Gutierrez-Choquevilca, Andréa-Luz; Lopez Mesia, Jean Pierre; Ruiz, Lastenia; Ruiz Macedo, Juan Celidonio; Abedini, Amin; Landoulsi, Ameni; Samaillie, Jennifer; Hennebelle, Thierry; Rivière, Céline; Neut, Christel

2015-10-01

Our survey was performed near Iquitos (Peruvian Amazon) and its surroundings and leads us to consider Mestizo ethnomedical practices. The plant species reported here are traditionally used for ailments related to microbial infections. Inhabitants of various ethnic origins were interviewed, and 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi-resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto (Peru). The minimum inhibitory concentrations (MICs) of the plant crude extracts were carried out using the agar dilution method and ranged between 0.075 and 5.0 mg/ml. Of the 40 plants analyzed, 9 species showed MIC ≤0.3 mg/ml (Anacardium occidentale, Couroupita guianensis, Croton lechleri, Davilla rugosa, Erythrina amazonica, Jacaranda copaia subsp. Spectabilis, Oenocarpus bataua, Peperomia macrostachya, and Phyllanthus urinaria) for one or several of the 36 microorganisms and only 6 drug extracts were inactive. Among the 40 plants, 13 were evaluated for the first time for an antibacterial activity. This evaluation of the antimicrobial activity of 40 plants using an approved standard methodology allowed comparing those activities against various microbes to establish antimicrobial spectra of standardized plant extracts, and give support to the traditional use of these plants. It may also help discovering new chemical classes of antimicrobial agents that could serve against multi-resistant bacteria. This study leads us to consider Mestizo ethnomedical practices near Iquitos (Peruvian Amazon) and its surroundings. The plant species reported here are traditionally used for ailments related to microbial infections. 52 selected plants extracts were evaluated for their antimicrobial properties against a panel of 36 sensitive and multi resistant bacteria or yeast. The study aimed at providing information on antimicrobial plant extract activities and the ethnomedical context of Mestizo riverine populations from Loreto.

Suggested guidelines for using systemic antimicrobials in bacterial skin infections: part 1—diagnosis based on clinical presentation, cytology and culture

PubMed Central

Beco, L.; Guaguère, E.; Méndez, C. Lorente; Noli, C.; Nuttall, T.; Vroom, M.

2013-01-01

Systemic antimicrobials are critically important in veterinary healthcare, and resistance is a major concern. Antimicrobial stewardship will be important in maintaining clinical efficacy by reducing the development and spread of antimicrobial resistance. Bacterial skin infections are one of the most common reasons for using systemic antimicrobials in dogs and cats. Appropriate management of these infections is, therefore, crucial in any policy for responsible antimicrobial use. The goals of therapy are to confirm that an infection is present, identify the causative bacteria, select the most appropriate antimicrobial, ensure that the infection is treated correctly, and to identify and manage any underlying conditions. This is the first of two articles that will provide evidence-led guidelines to help practitioners address these issues. This article covers diagnosis, including descriptions of the different clinical presentations of surface, superficial and deep bacterial skin infections, how to perform and interpret cytology, and how to best use bacterial culture and sensitivity testing. Part 2 will discuss therapy, including choice of drug and treatment regimens. PMID:23292951

Antimicrobial activity and cytotoxic effects of Magnolia dealbata and its active compounds.

PubMed

Jacobo-Salcedo, Maria del Rosario; Gonzalez-Espindola, Luis Angel; Alonso-Castro, Angel Josabad; Gonzalez-Martinez, Marisela del Rocio; Domínguez, Fabiola; Garcia-Carranca, Alejandro

2011-08-01

Multi-drug resistance is of great concern for public health worldwide and necessitates the search for new antimicrobials from sources such as plants. Several Magnolia (Magnoliaceae) species have been reported to exert antimicrobial effects on sensitive and multidrug-resistant microorganisms. However, the antimicrobial properties of Magnolia dealbata have not been experimentally evaluated. The antimicrobial effects of an ethanol extract of Magnolia dealbata seeds (MDE) and its active compounds honokiol (HK) and magnolol (MG) were tested against the phytopathogen Clavibacter michiganensis subsp. michiganensis and several human multi-drug resistant pathogens using the disk-diffusion assay. The effects of MDE and its active compounds on the viability of human peripheral blood mononuclear cells (PBMC) were evaluated using MTT assay. MDE and its active compounds had antimicrobial activity (inhibition zone > 10 mm) against C. michiganensis, Pseudomonas aeruginosa, Acinetobacter baumannii, Acinetobacter lwoffii, Candida albicans, Candida tropicalis and Trichosporon belgeii. The results suggest that M. dealbata and its active compounds have selective antimicrobial effects against drug-resistant fungal and Gram (-) bacteria and exert minimal toxic effects on human PMBC.

Microbioassay of Antimicrobial Agents

PubMed Central

Simon, Harold J.; Yin, E. Jong

1970-01-01

A previously described agar-diffusion technique for microbioassay of antimicrobial agents has been modified to increase sensitivity of the technique and to extend the range of antimicrobial agents to which it is applicable. This microtechnique requires only 0.02 ml of an unknown test sample for assay, and is capable of measuring minute concentrations of antibiotics in buffer, serum, and urine. In some cases, up to a 20-fold increase in sensitivity is gained relative to other published standardized methods and the error of this method is less than ±5%. Buffer standard curves have been established for this technique, concurrently with serum standard curves, yielding information on antimicrobial serum-binding and demonstrating linearity of the data points compared to the estimated regression line for the microconcentration ranges covered by this technique. This microassay technique is particularly well suited for pediatric research and for other investigations where sample volumes are small and quantitative accuracy is desired. Dilution of clinical samples to attain concentrations falling with the range of this assay makes the technique readily adaptable and suitable for general clinical pharmacological studies. The microassay technique has been standardized in buffer solutions and in normal human serum pools for the following antimicrobials: ampicillin, methicillin, penicillin G, oxacillin, cloxacillin, dicloxacillin, cephaloglycin, cephalexin, cephaloridine, cephalothin, erythromycin, rifamycin amino methyl piperazine, kanamycin, neomycin, streptomycin, colistin, polymyxin B, doxycycline, minocycline, oxytetracycline, tetracycline, and chloramphenicol. PMID:4986725

High mortality among patients infected with hypervirulent antimicrobial-resistant capsular type K1 Klebsiella pneumoniae strains in Taiwan.

PubMed

Lin, Yi-Tsung; Cheng, Yi-Hsiang; Juan, Chih-Han; Wu, Ping-Feng; Huang, Yi-Wei; Chou, Sheng-Hua; Yang, Tsuey-Ching; Wang, Fu-Der

2018-06-12

Capsular type K1 Klebsiella pneumoniae, highly virulent strains which are common in Asian countries, can cause pyogenic infections. These hypervirulent strains are usually susceptible to most antimicrobials, except for ampicillin. Little is known regarding the clinical and molecular characteristics of antimicrobial-resistant K1 K. pneumoniae strains. This retrospective study evaluated patients infected with capsular type K1 K. pneumoniae strains in a Taiwanese medical centre between April 2013 and March 2016. Antimicrobial-resistant strains were defined based on non-susceptibility to antimicrobial agents except ampicillin. We compared the clinical outcome of patients infected with and without antimicrobial-resistant strains. The in vivo virulence, genetic relatedness, and resistance mechanisms of these hypervirulent antimicrobial-resistant strains were also investigated. A total of 182 capsular type K1 K. pneumoniae strains were identified, including 18 antimicrobial-resistant strains. The 28-day mortality rate among the 18 cases caused by antimicrobial-resistant strains was significantly higher than that among 164 cases caused by antimicrobial-sensitive strains (50% vs. 10.4%, p < 0.001). Infection with antimicrobial-resistant strain independently increased the 28-day mortality risk. Most antimicrobial -resistant strains were not clonally related, and they exhibited high in vivo virulence in a mouse lethality experiment. The major resistance mechanisms involved the presence of β-lactamases and the overexpression of efflux pumps. In conclusion, hypervirulent antimicrobial-resistant capsular type K1 K. pneumoniae strains can predispose to a fatal outcome. These strains may represent an emerging threat to public health in Taiwan. Copyright © 2018. Published by Elsevier B.V.

Antimicrobial Susceptibility Patterns of Enterococcus faecalis and Enterococcus faecium Isolated from Poultry Flocks in Germany.

PubMed

Maasjost, J; Mühldorfer, K; Cortez de Jäckel S; Hafez, H M

2015-03-01

Between 2010 and 2011, 145 Enterococcus isolates (Enterococcus faecalis, n = 127; Enterococcus faecium, n = 18) were collected during routine bacteriologic diagnostics from broilers, layers, and fattening turkeys in Germany showing various clinical signs. The susceptibility to 24 antimicrobial agents was investigated by broth microdilution test to determine minimum inhibitory concentrations (MICs). All E. faecalis isolates (n = 127) were susceptible to the beta-lactam antibiotics ampicillin, amoxicillin-clavulanic acid, and penicillin. Corresponding MIC with 50% inhibition (MIC50) and MIC with 90% inhibition (MIC90) values of these antimicrobial agents were at the lower end of the test range (≤ 4 μg/ml). In addition, no vancomycin-resistant enterococci (VRE) were found. High resistance rates were identified in both Enterococcus species for lincomycin (72%-99%) and tetracycline (67%-82%). Half or more than half of Enterococcus isolates were resistant to gentamicin (54%-72%) and the macrolide antibiotics erythromycin (44%-61%) and tylosin-tartate (44%-56%). Enterococcus faecalis isolated from fattening turkeys showed the highest prevalence of antimicrobial resistance compared to other poultry production systems. Eighty-nine out of 145 Enterococcus isolates were resistant to three or more antimicrobial classes. Again, turkeys stood out with 42 (8 1%) multiresistant isolates. The most-frequent resistance patterns of E. faecalis were gentamicin, lincomycin, and tetracycline in all poultry production systems.

A Decennium of Etiology and Antimicrobial Susceptibility Patterns in Patients with Infective Endocarditis at a University Hospital, Thailand.

PubMed

Nakaranurack, Chotirat; Puttilerpong, Chankit; Suwanpimolkul, Gompol

2017-05-24

Infective endocarditis is an infection with a high mortality rate. Antimicrobial therapy is important for treatment, but data on antimicrobial susceptibilities are limited. This retrospective study analyzed data on the causative microorganisms and antimicrobial susceptibility patterns in patients with infective endocarditis 18 years of age or older who received inpatient care between 2006 and 2015 at King Chulalongkorn Memorial Hospital. A total of 213 patients fulfilled the inclusion criteria. Streptococcus spp. (54.5%) was the most common organism. Viridans streptococcus (46%) was the leading pathogen, followed by Group B streptococcus (27%). The majority of Streptococcus spp. were susceptible to penicillin (82.7%). Among Streptococcus spp., Streptococcus suis had the highest MIC 90 of penicillin and cefotaxime (1.65 and 0.95 μg/ml, respectively). There was a statistically significant increase in the MICs of penicillin and cefotaxime for Streptococcus suis (P = 0.03 and 0.04). Only 45.5% of Streptococcus suis and 77.5% of Viridans streptococcus were susceptible to penicillin. All Enterococcus spp. and Staphylococcus spp. were susceptible to vancomycin. In conclusion, the prevalence of Group B streptococcus isolates increased among patients with infective endocarditis in Thailand. Streptococcus suis had the highest MIC 90 and proportion of isolates not susceptible to penicillin. Rigorous restriction of the use of antimicrobial agents in animal feeds should be a primary concern.

Distribution of virulence determinants among antimicrobial-resistant and antimicrobial-susceptible Escherichia coli implicated in urinary tract infections.

PubMed

Stephenson, Sam; Brown, P D

2016-01-01

Uropathogenic Escherichia coli (UPEC) rely on the correlation of virulence expression with antimicrobial resistance to persist and cause severe urinary tract infections (UTIs). We assessed the virulence pattern and prevalence among UPEC strains susceptible and resistant to multiple antimicrobial classes. A total of 174 non-duplicate UPEC strains from patients with clinically significant UTIs were analysed for susceptibility to aminoglycoside, antifolate, cephalosporin, nitrofuran and quinolone antibiotics for the production of extended-spectrum β-lactamases and for the presence of six virulence determinants encoding adhesins (afimbrial, Type 1 fimbriae, P and S-fimbriae) and toxins (cytotoxic necrotising factor and haemolysin). Relatively high resistance rates to nalidixic acid, ciprofloxacin, cephalothin and trimethoprim-sulfamethoxazole (82%, 78%, 62% and 59%, respectively) were observed. Fourteen distinct patterns were identified for the virulence determinants such as afaBC, cnfI, fimH, hylA, papEF and sfaDE. The toxin gene, cnfI (75.3%), was the second most prevalent marker to the adhesin, fimH (97.1%). The significant association of sfaDE/hylA (P < 0.01) among antimicrobial resistant and susceptible strains was also observed notwithstanding an overall greater occurrence of virulence factors among the latter. This study provides a snapshot of UPEC complexity in Jamaica and highlights the significant clonal heterogeneity among strains. Such outcomes emphasise the need for evidence-based strategies in the effective management and control of UTIs.

Antimicrobial susceptibility and genetic relatedness of respiratory tract pathogens in weaner pigs over a 12-month period.

PubMed

Niemann, Lisa; Müller, Petra; Brauns, Jasmin; Nathaus, Rolf; Schäkel, Franziska; Kipschull, Kerstin; Höltig, Doris; Wendt, Michael; Schwarz, Stefan; Kadlec, Kristina

2018-06-01

The collaboration project VASIB aims at reducing the antibiotic consumption in pig production by integrating information from consulting expertise in clinical inspection, hygiene, epidemiology, microbiology and pharmacology. In this VASIB subproject, we investigated the antimicrobial susceptibility and relatedness of porcine respiratory tract pathogens. Bordetella bronchiseptica (n = 47), Pasteurella multocida (n = 18) and Streptococcus suis (n = 58) were obtained from weaner pigs at two farms. Antimicrobial susceptibility testing was performed by broth microdilution according to CLSI standards. Resistance genes were detected via specific PCR assays. Macrorestriction analysis was conducted to determine the relatedness of the isolates and to identify clones. The B. bronchiseptica isolates showed indistinguishable (farm 1) or two closely related XbaI-patterns (farm 2). Different SmaI-PFGE patterns of P. multocida isolates were obtained at three different time points. In contrast, PFGE analysis of S. suis indicated more than one fragment pattern per pig and time point. Isolates exhibiting indistinguishable PFGE patterns were considered to represent the same clone. This study showed that only two closely related B. bronchiseptica clones were present in both farms, which had low MICs to all antimicrobials, except to β-lactams. Different P. multocida clones were present at the three time points. They showed overall low MIC values, with two clones being resistant and one intermediate to tetracycline. S. suis clones were resistant to tetracycline (n = 19) and/or erythromycin/clindamycin (n = 16). They harboured the tetracycline resistance genes tet(O), tet(M) or tet(L) and/or the macrolide/lincosamide/streptogramin B resistance gene erm(B). Five penicillin-resistant S. suis clones were also detected. Copyright © 2018 Elsevier B.V. All rights reserved.

Drug Resistance Patterns of Escherichia coli in Ethiopia: A Meta-Analysis.

PubMed

Tuem, Kald Beshir; Gebre, Abadi Kahsu; Atey, Tesfay Mehari; Bitew, Helen; Yimer, Ebrahim M; Berhe, Derbew Fikadu

2018-01-01

Antimicrobial drug resistance is a global threat for treatment of infectious diseases and costs life and money and threatens health delivery system's effectiveness. The resistance of E. coli to frequently utilized antimicrobial drugs is becoming a major challenge in Ethiopia. However, there is no inclusive countrywide study. Therefore, this study intended to assess the prevalence of E. coli resistance and antimicrobial-specific resistance pattern among E. coli clinical isolates in Ethiopia. Articles were retrieved from PubMed, Embase, and grey literature from 2007 to 2017. The main outcome measures were overall E. coli and drug-specific resistance patterns. A random-effects model was used to determine pooled prevalence with 95% confidence interval (CI), using DerSimonian and Laird method. In addition, subgroup analysis was conducted to improve the outcome. The study bias was assessed by Begg's funnel plot. This study was registered in PROSPERO as follows: PROSPERO 2017: CRD42017070106. Of 164 articles retrieved, 35 articles were included. A total of 19,235 study samples participated in the studies and 2,635 E. coli strains were isolated. Overall, E. coli antibacterial resistance was 45.38% (95% confidence interval (CI): 33.50 to 57.27). The resistance pattern ranges from 62.55% in Addis Ababa to 27.51% in Tigray region. The highest resistance of E. coli reported was to ampicillin (83.81%) and amoxicillin (75.79%), whereas only 13.55% of E. coli isolates showed resistance to nitrofurantoin. E. coli antimicrobial resistance remains high with disparities observed among regions. The bacterium was found to be highly resistant to aminopenicillins. The finding implies the need for effective prevention strategies for the E. coli drug resistance and calls for multifaceted approaches with full involvement of all stakeholders.

Antimicrobial Wound Dressing. Phase 1

DTIC Science & Technology

1987-06-11

12 a. Antimicrobial Sensitivity Tests 12 b. Anin.il Model 13 5. Preparatiua of Microcapsules 14 B. Results 15 1. AIn Vit Diffusion 15 a. PVA... Microcapsules 35 Table 5 Tetracycline Hydrochloride Cellulose 36 Triacetate Microcapsules Table 6 Polyethylene Oxide Hydrogels 37 Table 7 Swelling of...Water and Crosslinking Effect Figure 24 In Vi trq Chlorhexidine Release 70 Polyacrylamide Hydrogel - Microcapsules Figure 25 In _Vitro Tetracycline

The prevalence of antimicrobial-resistant Escherichia coli in sympatric wild rodents varies by season and host.

PubMed

Williams, N J; Sherlock, C; Jones, T R; Clough, H E; Telfer, S E; Begon, M; French, N; Hart, C A; Bennett, M

2011-04-01

  To investigate the prevalence and temporal patterns of antimicrobial resistance in wild rodents with no apparent exposure to antimicrobials.   Two sympatric populations of bank voles and wood mice were trapped and individually monitored over a 2- year period for faecal carriage of antimicrobial-resistant Escherichia coli. High prevalences of ampicillin-, chloramphenicol-, tetracycline- and trimethoprim-resistant E. coli were observed. A markedly higher prevalence of antimicrobial-resistant E. coli was found in wood mice than in bank voles, with the prevalence in both increasing over time. Superimposed on this trend was a seasonal cycle with a peak prevalence of resistant E. coli in mice in early- to mid-summer and in voles in late summer and early autumn.   These sympatric rodent species had no obvious contact with antimicrobials, and the difference in resistance profiles between rodent species and seasons suggests that factors present in their environment are unlikely to be drivers of such resistance.   These findings suggest that rodents may represent a reservoir of antimicrobial-resistant bacteria, transmissible to livestock and man. Furthermore, such findings have implications for human and veterinary medicine regarding antimicrobial usage and subsequent selection of antimicrobial-resistant organisms. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

AFNOR validation of Premi Test, a microbiological-based screening tube-test for the detection of antimicrobial residues in animal muscle tissue.

PubMed

Gaudin, Valerie; Juhel-Gaugain, Murielle; Morétain, Jean-Pierre; Sanders, Pascal

2008-12-01

Premi Test contains viable spores of a strain of Bacillus stearothermophilus which is sensitive to antimicrobial residues, such as beta-lactams, tetracyclines, macrolides and sulphonamides. The growth of the strain is inhibited by the presence of antimicrobial residues in muscle tissue samples. Premi Test was validated according to AFNOR rules (French Association for Normalisation). The AFNOR validation was based on the comparison of reference methods (French Official method, i.e. four plate test (FPT) and the STAR protocol (five plate test)) with the alternative method (Premi Test). A preliminary study was conducted in an expert laboratory (Community Reference Laboratory, CRL) on both spiked and incurred samples (field samples). Several method performance criteria (sensitivity, specificity, relative accuracy) were estimated and are discussed, in addition to detection capabilities. Adequate agreement was found between the alternative method and the reference methods. However, Premi Test was more sensitive to beta-lactams and sulphonamides than the FPT. Subsequently, a collaborative study with 11 laboratories was organised by the CRL. Blank and spiked meat juice samples were sent to participants. The expert laboratory (CRL) statistically analysed the results. It was concluded that Premi Test could be used for the routine determination of antimicrobial residues in muscle of different animal origin with acceptable analytical performance. The detection capabilities of Premi Test for beta-lactams (amoxicillin, ceftiofur), one macrolide (tylosin) and tetracycline were at the level of the respective maximum residue limits (MRL) in muscle samples or even lower.

Improved agar diffusion method for detecting residual antimicrobial agents.

PubMed

Tsai, C E; Kondo, F

2001-03-01

The improved agar diffusion method for determination of residual antimicrobial agents was investigated, and the sensitivities of various combinations of test organisms and assay media were determined using 7 organisms, 5 media, and 31 antimicrobial agents. Bacillus stearothermophilus and synthetic assay medium (SAM) showed the greatest sensitivity for screening penicillins (penicillin G and ampicillin). The combination of Bacillus subtilis and minimum medium (MM) was the most sensitive for tetracyclines (oxytetracycline and chlortetracycline), B. stearothermophilus and SAM or Micrococcus luteus and Mueller-Hinton agar (MHA) for detecting tylosin and erythromycin, B. subtilis and MHA for aminoglycosides (streptomycin, kanamycin, gentamicin, and dihydrostreptomycin), B. stearothermophilus and SAM for polyethers (salinomycin and lasalocid), and B. subtilis and MM or Clostridium perfringens and GAM for polypeptides (thiopeptin, enramycin, virginiamycin, and bacitracin). However, gram-negative bacterium Escherichia coli ATCC 27166 and MM were better for screening for colistin and polymixin-B. For detecting the synthetic drugs tested, the best combination was B. subtilis and MM for sulfonamides, E. coli 27166 and MM for quinolones (oxolinic acid and nalidixic acid), B. subtilis and MM for furans (furazolidone), and the bioluminescent bacterium Photobacterium phosphoreum and luminescence assay medium for chloramphenicol and oxolinic acid. The results showed that the use of four assay plates, B. stearothermophilus and SAM, B. subtilis and MM, M. luteus and MHA, and E. coli 27166 and MM, was superior to the currently available techniques for screening for residual antimicrobial agents in edible animal tissues.

In-vitro antimicrobial activity and identification of bioactive components using GC-MS of commercially available essential oils in Saudi Arabia.

PubMed

Ashraf, Syed Amir; Al-Shammari, Eyad; Hussain, Talib; Tajuddin, Shaikh; Panda, Bibhu Prasad

2017-11-01

This study was designed to evaluate antimicrobial activity and chemical composition of four different plant essential oils i.e. Ginger oil (GiO), Black seed oil (BSO), Oregano oil (OO) and Rose oil (RO) against different bacterial and fungal strains. Anti-microbial activities of selected essential oils were determined by the microbiological technique using Agar well diffusion assay. After in vitro study, most of the essential oils showed antimicrobial activity against all the selected pathogens. Among all the tested oils, GiO showed strong antimicrobial activity. GiO showed highest antimicrobial activity against Shigella (119.79%), Enteococcus hirae (110.61%) and Escherichia coli (106.02%), when compared with the tetracycline (50 µg/mL) activity. However, Antifungal activity of GiO was found to be present against Candida albicans and Aspergilluas flavus , when compared with clotrimazole (50 µg/mL) activity. Among all the selected bacteria, BSO showed maximum antimicrobial activity against the E. coli followed by Citrobacter freundii. Moreover, BSO had highest zone of inhibition against the C. ablicans (33.58%). OO indicated that, Shigella had the highest sensitivity (12.6 ± 0.58, 131.25%), followed by E. hirae (19.1 ± 0.61, 96.46%) and Salmonella typhi (15.2 ± 0.27, 83.06%) when compared with tetracycline activity. OO showed poor sensitivity against all the selected fungal strains. Furthermore, Gas Chromatography analysis revealed that, Gingerol (10.86%) was the chief chemical constituents found in GiO followed by α -Sesquiphellandrene (6.29%), Zingiberene (5.88%). While, BSO, OO and RO had higher percentage of p-Cymene (6.90%), Carvacrol (15.87%) and Citronellol (8.07%) respectively. The results exhibited that the essential oils used for this study was the richest source for antimicrobial activity which indicates the presence of broad spectrum antimicrobial compounds in these essential oils. Hence, essential oils and their components can be recommended for therapeutic purposes as source of an alternative medicine.

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.

Changing patterns of drug-resistant Shigella isolates in egypt.

PubMed

Abd-Elmeged, Ghada M; Khairy, Rasha M; Abo-Eloyoon, Sahar M; Abdelwahab, Sayed F

2015-06-01

The emergence of multidrug resistance (MDR) is a serious problem in treating shigellosis. There are limited existing data examining the change in the antimicrobial resistance profile of Shigella in Egypt. We previously reported that 58% of the Shigella isolates in Egypt were resistant to at least one member of the three different antimicrobial groups. This study was performed to determine the antimicrobial resistance profile of Shigella, determine their possible mechanisms of resistance, and compare their resistance profile to those reported 20 years ago. Stool samples were collected from 500 subjects and processed for the isolation and identification of Shigella. The susceptibility of the isolates to 11 different antimicrobials was determined using the disc diffusion method. Of 500 stool cultures, 24 (4.8%) samples were positive for Shigella. There was a high percentage of resistance to ampicillin (88%), tetracycline (83%), and sulfamethoxazole-trimethoprim (75%). Also, there was a moderate percentage of resistance to chloramphenicol (46%), streptomycin (42%), ceftazidime (33%), and cefotaxime (25%). A lower percentage of resistance was recorded for amikacin, nalidixic acid (17% each), and ofloxacin (7%), while no resistance was found to ciprofloxacin (0%). Twenty-one of the isolates (88%) were resistant to at least three different antimicrobial groups (indicating MDR). The average number of antimicrobial agents to which the Shigella isolates were resistant was 4.3±1.4, while it was 3.4±1.5 in the same locality in 1994. These data demonstrate that there is a marked increase in MDR and change in the resistance patterns of Shigella over the past 20 years.

Orbital abscess bacterial isolates and in vitro antimicrobial susceptibility patterns in dogs and cats.

PubMed

Wang, Annie L; Ledbetter, Eric C; Kern, Thomas J

2009-01-01

To determine bacterial populations, in vitro antimicrobial susceptibility patterns, and sources of microorganisms for dogs and cats with orbital abscess. In total, 34 dogs and 7 cats with orbital abscess participated in the study. Medical records of dogs and cats with a clinical diagnosis of orbital abscess, confirmed by cytologic or histopathologic evaluation of orbital specimens, were reviewed from the years 1990 to 2007. Animal signalment, presumptive source of microorganisms and mechanism of orbital introduction, bacterial isolates, and aerobic bacterial in vitro antimicrobial susceptibility test results were recorded. Percentages of susceptible aerobic bacterial isolates were compared among antimicrobials. Twenty dogs and five cats had positive culture results. The most frequent bacterial genera isolated from dogs were Staphylococcus, Escherichia, Bacteroides, Clostridium and Pasteurella. The most frequent bacterial genera isolated from cats were Pasteurella and Bacteroides. Aerobic bacterial isolates from dogs had the highest percentage of susceptibility to amikacin, ceftiofur, gentamicin, imipenem, ticarcillin and trimethoprim-sulfamethoxazole. Aerobic bacterial isolates from dogs had the lowest percentage of susceptibility to ampicillin, clindamycin, erythromycin and penicillin. Antimicrobial resistance was uncommon among feline aerobic bacterial isolates. The most commonly identified routes of orbital bacteria introduction were extension from adjacent anatomical structures, penetrating exogenous trauma, and foreign bodies. Mixed aerobic and anaerobic bacterial infections of the orbit occur commonly in dogs and cats. On the basis of aerobic and anaerobic bacterial isolates and in vitro susceptibility testing of aerobic bacterial isolates, cephalosporins, extended-spectrum penicillins, potentiated-penicillins and carbapenems are recommended for initial antimicrobial therapy of orbital abscess in dogs and cats.

Antimicrobial resistance among Salmonella isolates from hospitals in Rome.

PubMed Central

Falbo, V.; Caprioli, A.; Mondello, F.; Cacace, M. L.; Luzi, S.; Greco, D.

1982-01-01

The susceptibility to antimicrobial agents of 569 salmonella isolated collected in 1977-8 from patients in hospitals in Rome was tested. Fifty-nine per cent of all isolates were resistant to one or more antimicrobials. Resistance was most common to sulphathiazole, tetracycline, streptomycin, whereas colistin, gentamicin, tobramycin, trimethoprim-sulphamethoxazole and nalidixic acid were the most active in vitro. Multiple resistance was most frequently found in strains of Salmonella wien and S. typhimurium (94% and 38% respectively). A significant change in the resistance pattern of S. wien was observed between 1977 and 1978, with a significant increase of susceptibility to some antimicrobials in 1978. Twenty-one R-plasmids transmissible to E. coli K12 were derived from 46 resistant strains of S. typhimurum. PMID:7061839

[Antimicrobial susceptibility patterns of Gram-negative bacteria isolated in urinary tract infections in Venezuela: Results of the SMART study 2009-2012].

PubMed

Guevara, Napoleón; Guzmán, Manuel; Merentes, Altagracia; Rizzi, Adele; Papaptzikos, Juana; Rivero, Narlesky; Oranges, Carmela; Vlllarroel, Héctor; Limas, Yoxsivell

2015-12-01

Antimicrobial resistance of pathogens causing urinary tract infection (UTI) is a growing problem, which complicates their effective treatment. Surveillance is needed to guide appropriate empiric therapy. to describe the susceptibility patterns of Gram-negative bacteria isolated of patients with UTI to twelve antibiotics as part of the Study for Monitoring Antimicrobial Resistance Trends in Venezuela. Between 2009-2012 a total of 472 Gram-negative bacteria were isolated from hospitalized patients with UTI. The isolates were sent to Central Laboratory (Central Laboratory of International Health Management Associates) to confirm their identification, and to make susceptibility testing as recommended by the Clinical and Laboratory Standards Institute. Enterobacteriacea comprised 96.6% of the total, where Escherichia coli (76.9%) and Klebsiella pneumoniae (10.6%) were the most frequent. Extended-spectrum β-lactamases (ESBL) was detected in 21.6% of isolates. Top antimicrobial activity were ertapenem, imipenem, and amikacin (> 90.0%), slightly lower for amikacin (85.1%) in ESBL-producing strains. Resistance rates to fluoroquinolones and ampicillin/sulbactam were high (40 y 64%, respectively). These data suggest a necessary revision of the therapeutic regimens for the empirical treatment of UTI in Venezuela.

Trends in ophthalmic antimicrobial utilization pattern in Bahrain between 1993 and 2000: a resurgence of chloramphenicol?

PubMed

Jassim Al Khaja, K A; Sequeira, R R; Mathur, V S

2003-01-01

The occurrence of aplastic anemia following topical administration of ophthalmic chloramphenicol is controversial and debated internationally. We have determined the influence of such debate on the utilization of ophthalmic chloramphenicol in Bahrain, through studying the utilization patterns of ophthalmic antimicrobial preparations by the Ministry of Health, with an emphasis on chloramphenicol, between 1993 and 2000. Cost-implications of these patterns are examined. Information on the annual purchase of ophthalmic antimicrobial drug preparations and their unit price was obtained from the Directorate of Materials Management, Ministry of Health, and analyzed. In 1993, the 3 most commonly purchased ophthalmic antibacterial preparations were oxytetracycline 1% eye ointment (40.1%); sulfacetamide 10% and 20% eye drops (25.3%); and chloramphenicol 0.5% eye drops and 1% eye ointment (10.8%). In 2000, oxytetracycline remained the most frequently purchased preparation (33%), followed by chloramphenicol (21.2%). Between 1993 and 1999, chloramphenicol purchases fluctuated between 10% to 16.4% with a remarkable increase to 21.2%, in 2000. Chloramphenicol accounted for 8.6% and 15.1% of cost of total ophthalmic preparations purchased in 1993 and 2000, respectively. Despite continued concerns of potential risks of ophthalmic chloramphenicol, this preparation is extensively utilized in Bahrain. We are of the opinion that for minor infections, chloramphenicol ophthalmic preparations should be replaced by safer alternatives. Further, we recommend that their use be reserved for ocular infections that are resistant to other antimicrobials, and that ophthalmologists, at the secondary care level, should supervise such treatment.

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.

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.

Antimicrobial autophagy: a conserved innate immune response in Drosophila.

PubMed

Moy, Ryan H; Cherry, Sara

2013-01-01

Autophagy is a highly conserved degradative pathway that has rapidly emerged as a critical component of immunity and host defense. Studies have implicated autophagy genes in restricting the replication of a diverse array of pathogens, including bacteria, viruses and protozoans. However, in most cases, the in vivo role of antimicrobial autophagy against pathogens has been undefined. Drosophila provides a genetically tractable model system that can be easily adapted to study autophagy in innate immunity, and recent studies in flies have demonstrated that autophagy is an essential antimicrobial response against bacteria and viruses in vivo. These findings reveal striking conservation of antimicrobial autophagy between flies and mammals, and in particular, the role of pathogen-associated pattern recognition in triggering this response. This review discusses our current understanding of antimicrobial autophagy in Drosophila and its potential relevance to human immunity. Copyright © 2013 S. Karger AG, Basel.

A national survey of antimicrobial prophylaxis in adult cardiac surgery across Canada

PubMed Central

Paradiso-Hardy, Fran L; Cornish, Patti; Pharand, Chantal; Fremes, Stephen E

2002-01-01

OBJECTIVE: To characterize national and regional patterns of antimicrobial prophylaxis in adult cardiac surgery across Canada. DESIGN: Retrospective, cross-sectional analysis. SETTING: Thirty-three adult cardiac surgical centres across Canada. INTERVENTIONS: A one-page questionnaire collecting information regarding institutional demographics and antimicrobial prophylaxis regimens for adult cardiac surgical procedures was mailed to all adult surgical centres across Canada. If a response was not received within one month, a second survey was mailed, followed by a telephone reminder within two weeks of the second mailing. MAIN RESULTS: The Overall response rate was 100%. Prophylactic antimicrobials were used in all the adult cardiac centres; single-agent prophylaxis was used in 97% (32 of 33) of centres; Single-dose antimicrobial prophylaxis was used in only 3% (one of 33) of centres. Preoperative and postoperative antimicrobial prophylaxis regimens varied both between provinces and within provinces across Canada. Cefazolin was the antimicrobial used in 88% (38 of 43) and 87% (33 of 38) of the reported pre-operative and post-operative prophylaxis regimens, respectively. Antimicrobial prophylaxis was initiated in the operating room 72% (26 of 36) of the time and intra-operative supplemental antimicrobial doses were administered for cardiac procedures longer than a median of 4 hours (range 4 to 8 hr). Overall, the median duration of antimicrobial prophylaxis was 36 hours (range 8 to 96 hr). CONCLUSIONS: Despite the availability of various published guidelines, our survey identified several areas for improvement with respect to antimicrobial prophylaxis in adult cardiac surgery across Canada. PMID:18159370

Prevalence and antimicrobial resistance pattern of bacterial meningitis in Egypt

PubMed Central

Shaban, Lamyaa; Siam, Rania

2009-01-01

Infectious diseases are the leading cause of morbidity and mortality in the developing world. In Egypt bacterial diseases constitute a great burden, with several particular bacteria sustaining the leading role of multiple serious infections. This article addresses profound bacterial agents causing a wide array of infections including but not limited to pneumonia and meningitis. The epidemiology of such infectious diseases and the prevalence of Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae are reviewed in the context of bacterial meningitis. We address prevalent serotypes in Egypt, antimicrobial resistance patterns and efficacy of vaccines to emphasize the importance of periodic surveillance for appropriate preventive and treatment strategies. PMID:19778428

Antimicrobial Resistance of Faecal Escherichia coli Isolates from Pig Farms with Different Durations of In-feed Antimicrobial Use.

PubMed

Gibbons, J F; Boland, F; Egan, J; Fanning, S; Markey, B K; Leonard, F C

2016-05-01

Antimicrobial use and resistance in animal and food production are of concern to public health. The primary aims of this study were to determine the frequency of resistance to 12 antimicrobials in Escherichia coli isolates from 39 pig farms and to identify patterns of antimicrobial use on these farms. Further aims were to determine whether a categorization of farms based on the duration of in-feed antimicrobial use (long-term versus short-term) could predict the occurrence of resistance on these farms and to identify the usage of specific antimicrobial drugs associated with the occurrence of resistance. Escherichia coli were isolated from all production stages on these farms; susceptibility testing was carried out against a panel of antimicrobials. Antimicrobial prescribing data were collected, and farms were categorized as long term or short term based on these. Resistance frequencies and antimicrobial use were tabulated. Logistic regression models of resistance to each antimicrobial were constructed with stage of production, duration of antimicrobial use and the use of 5 antimicrobial classes included as explanatory variables in each model. The greatest frequencies of resistance were observed to tetracycline, trimethoprim/sulphamethoxazole and streptomycin with the highest levels of resistance observed in isolates from first-stage weaned pigs. Differences in the types of antimicrobial drugs used were noted between long-term and short-term use farms. Categorization of farms as long- or short-term use was sufficient to predict the likely occurrence of resistance to 3 antimicrobial classes and could provide an aid in the control of resistance in the food chain. Stage of production was a significant predictor variable in all models of resistance constructed and did not solely reflect antimicrobial use at each stage. Cross-selection and co-selection for resistance was evident in the models constructed, and the use of trimethoprim/sulphonamide drugs in particular was associated with the occurrence of resistance to other antimicrobials. © 2015 Blackwell Verlag GmbH.

An Exploratory Descriptive Study of Antimicrobial Resistance Patterns of Staphylococcus Spp. Isolated from Horses Presented at a Veterinary Teaching Hospital.

PubMed

Oguttu, James Wabwire; Qekwana, Daniel Nenene; Odoi, Agricola

2017-08-22

Antimicrobial resistant Staphylococcus are becoming increasingly important in horses because of the zoonotic nature of the pathogens and the associated risks to caregivers and owners. Knowledge of the burden and their antimicrobial resistance patterns are important to inform control strategies. This study is an exploratory descriptive investigation of the burden and antimicrobial drug resistance patterns of Staphylococcus isolates from horses presented at a veterinary teaching hospital in South Africa. Retrospective laboratory clinical records of 1027 horses presented at the University of Pretoria veterinary teaching hospital between 2007 and 2012 were included in the study. Crude and factor-specific percentages of Staphylococcus positive samples, antimicrobial resistant (AMR) and multidrug resistant (MDR) isolates were computed and compared across Staphylococcus spp., geographic locations, seasons, years, breed and sex using Chi-square and Fisher's exact tests. Of the 1027 processed clinical samples, 12.0% were Staphylococcus positive. The majority of the isolates were S. aureus (41.5%) followed by S. pseudintermedius (14.6%). Fifty-two percent of the Staphylococcus positive isolates were AMR while 28.5% were MDR. Significant (p < 0.05) differences in the percentage of samples with isolates that were AMR or MDR was observed across seasons, horse breeds and Staphylococcus spp. Summer season had the highest (64.3%) and autumn the lowest (29.6%) percentages of AMR isolates. Highest percentage of AMR samples were observed among the Boerperds (85.7%) followed by the American saddler (75%) and the European warm blood (73.9%). Significantly (p < 0.001) more S. aureus isolates (72.5%) were AMR than S. pseudintermedius isolates (38.9%). Similarly, significantly (p < 0.001) more S. aureus (52.9%) exhibited MDR than S. pseudintermedius (16.7%). The highest levels of AMR were towards β-lactams (84.5%) followed by trimethoprim/sulfamethoxazole (folate pathway inhibitors) (60.9%) while the lowest levels of resistance were towards amikacin (14.%). This exploratory study provides useful information to guide future studies that will be critical for guiding treatment decisions and control efforts. There is a need to implement appropriate infection control, and judicious use of antimicrobials to arrest development of antimicrobial resistance. A better understanding of the status of the problem is a first step towards that goal.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goven, A.J.; Chen, S.C.; Fitzpatrick, L.C.

Lysozyme activity in earthworm (Lumbricus terrestris) coelomic fluid and coelomocytes appears sufficiently sensitive for use as a nonmammalian biomarker to detect toxic effects of sublethal body burdens of Cu[sup 2+]. Lysozyme, a phylogenetically conserved enzyme, is capable of bactericidal activity via action on peptidoglycan of gram-positive bacterial cell walls and functions as a component of an organism's innate antimicrobial defense mechanism. Coelomic fluid and coelomocyte lysozyme activities, which exhibit temperature-response patterns similar to those of human saliva, plasma, serum and leukocyte extracts, were sensitive to Cu[sup 2+] exposure. Lysozyme activity of coelomic fluid and coelomocyte extracts from earthworms exposed formore » 5 d to CuSO[sub 4], using filter paper contact exposure, decreased with increasing sublethal Cu[sup 2+] concentrations of 0.05 and 0.1 [mu]g/cm[sup 2]. Compared to controls, coelomic fluid lysozyme activity was suppressed significantly at both exposure concentrations, whereas coelomocyte extract lysozyme activity was suppressed significantly at the 0.1-[mu]g/cm[sup 2] exposure concentration. Low inherent natural variability and sensitivity to sublethal Cu[sup 2+] body burdens indicate that lysozyme activity has potential as a biomarker for assaying immunotoxicity of metals.« less

Genetic characteristics and antimicrobial resistance of Escherichia coli from Japanese macaques (Macaca fuscata) in rural Japan.

PubMed

Ogawa, Keiko; Yamaguchi, Keiji; Suzuki, Masatsugu; Tsubota, Toshio; Ohya, Kenji; Fukushi, Hideto

2011-04-01

Escherichia coli was isolated from wild and captive Japanese macaques (Macaca fuscata) to investigate the risk of zoonotic infections and the prevalence of antimicrobial-resistant Escherichia coli in the wild macaque population in Shimokita Peninsula, a rural area of Japan. We collected 265 fresh fecal samples from wild macaques and 20 samples from captive macaques in 2005 and 2006 for E. coli isolation. The predominant isolates were characterized by serotyping, virulence gene profiling, plasmid profiling, pulsed-field gel electrophoresis (PFGE), and microbial sensitivity tests. In total, 248 E. coli strains were isolated from 159 fecal samples from wild macaques, and 42 E. coli were isolated from 17 samples from captive macaques. None of the virulence genes eae, stx, elt, and est were detected in any of the isolates. The relatedness between wild- and captive-derived isolates was low by serotyping, PFGE, and plasmid profiling. Serotypes O8:H6, O8:H34, O8:H42, O8:HUT, O103:H27, O103:HNM, and OUT:H27 were found in wild macaque feces; serotypes O157:H42 and O119:H21 were recovered from captive macaques. O-and H-serotypes of the 26 isolates were not typed by commercial typing antisera and were named OUT and HUT, respectively. Twenty-eight isolates had no flagellar antigen, and their H-serotypes were named HNM. Similarity of PFGE patterns between wild-derived isolates and captive-derived isolates was <70%. No plasmid profile was shared between wild-derived and captive-derived isolates. The prevalence of antimicrobial-resistant E. coli was 6.5% (n=62) in wild macaques, and these isolates were resistant to cephalothin. We conclude that wild Japanese macaques in Shimokita Peninsula were unlikely to act as a reservoir of pathogenic E. coli for humans and that antimicrobial-resistant E. coli in wild macaques may be derived from humans.

Another Setting for Stewardship: High Rate of Unnecessary Antimicrobial Use in a VA Long-Term Care Facility

PubMed Central

Peron, Emily P.; Hirsch, Amy A.; Jury, Lucy A.; Jump, Robin L.P.; Donskey, Curtis J.

2015-01-01

BACKGROUND/OBJECTIVE Antimicrobials are frequently prescribed in long-term care facilities (LTCFs). In order to develop effective stewardship interventions, there is a need for data on current patterns of unnecessary antimicrobial prescribing among LTCF residents. The objective of this study was to examine the frequency of, reasons for, and adverse effects of unnecessary antimicrobial use in our Veterans Affairs (VA) LTCF. DESIGN Retrospective chart review. SETTING Cleveland VA Medical Center LTCF. PARTICIPANTS Randomly selected patients receiving antimicrobial therapy from October 1, 2008 to March 31, 2009. MEASUREMENTS Days of necessary and unnecessary antimicrobial therapy determined using Infectious Diseases Society of America guidelines, syndromes treated with unnecessary antimicrobials, and the frequency of development of Clostridium difficile infection (CDI), colonization or infection with antimicrobial resistant pathogens, and other adverse effects. RESULTS Of 1351 days of therapy prescribed in 100 regimens, 575 days (42.5%) were deemed unnecessary. Of the 575 unnecessary days of therapy, 334 (58%) were for antimicrobial regimens that were entirely unnecessary (n=42). Asymptomatic bacteriuria was the most common reason for entirely unnecessary regimens (n=21), resulting in 173 days of unnecessary therapy. Regimens that were partially unnecessary resulted in 241 (42%) days of unnecessary therapy, with longer than recommended treatment duration accounting for 226 (94%) unnecessary days of therapy. Within 30 days of completing the antimicrobial regimens, 5 patients developed CDI, 5 had colonization or infection with antimicrobial-resistant pathogens, and 10 experienced other adverse drug events. CONCLUSIONS In our VA LTCF, 43% of all days of antimicrobial therapy were unnecessary. Our findings suggest that antimicrobial stewardship interventions in LTCFs should focus on improving adherence to recommended treatment durations and eliminating inappropriate treatment of asymptomatic bacteriuria. PMID:23405923

Antimicrobial Activities of Clove and Thyme Extracts

PubMed Central

Nzeako, B C; Al-Kharousi, Zahra S N; Al-Mahrooqui, Zahra

2006-01-01

Objective: It has been postulated that geographical locations of the herbs affect the constituents of their essential oils and thus the degree of their antimicrobial action. This study examine two samples of clove obtained from Sri Lanka and Zanzibar and two samples of thyme from Iran and Oman to determine the antimicrobial potential of their extracted oils. Method: The active agents in each plant were extracted by steam distillation and by boiling. The antimicrobial activities of the extracts were determined at neat and by two-fold dilutions in well agar diffusion technique using Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Streptococcus pyogenes, Corynebacterium species, Salmonella species, Bacteroides fragilis and Candida albicans. Results: All oil extracts possessed antimicrobial activity against all bacteria and yeast tested. Their water extracts exhibited lower antimicrobial activity, though thyme aqueous extract was active only against S. aureus. The lowest concentration of antimicrobial activity (0.1% i.e., 1:1024) was obtained with thyme oil extract using Candida albicans. There was no significant difference in antimicrobial activity between clove obtained from Sri Lanka or Zanzibar or thyme obtained from Iran or Oman. Conclusion: Our experiment showed that the country of origin of the herbs has no effect on their antimicrobial activity. However, further work is necessary to ascertain why Candida albicans displayed remarkable degree of sensitivity with the extracts than all the other organisms test. PMID:21748125

Antimicrobial residues in animal waste and water resources proximal to large-scale swine and poultry feeding operations

USGS Publications Warehouse

Campagnolo, E.R.; Johnson, K.R.; Karpati, A.; Rubin, C.S.; Kolpin, D.W.; Meyer, M.T.; Esteban, J. Emilio; Currier, R.W.; Smith, K.; Thu, K.M.; McGeehin, M.

2002-01-01

Expansion and intensification of large-scale animal feeding operations (AFOs) in the United States has resulted in concern about environmental contamination and its potential public health impacts. The objective of this investigation was to obtain background data on a broad profile of antimicrobial residues in animal wastes and surface water and groundwater proximal to large-scale swine and poultry operations. The samples were measured for antimicrobial compounds using both radioimmunoassay and liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) techniques. Multiple classes of antimicrobial compounds (commonly at concentrations of >100 μg/l) were detected in swine waste storage lagoons. In addition, multiple classes of antimicrobial compounds were detected in surface and groundwater samples collected proximal to the swine and poultry farms. This information indicates that animal waste used as fertilizer for crops may serve as a source of antimicrobial residues for the environment. Further research is required to determine if the levels of antimicrobials detected in this study are of consequence to human and/or environmental ecosystems. A comparison of the radioimmunoassay and LC/ESI-MS analytical methods documented that radioimmunoassay techniques were only appropriate for measuring residues in animal waste samples likely to contain high levels of antimicrobials. More sensitive LC/ESI-MS techniques are required in environmental samples, where low levels of antimicrobial residues are more likely.

Pharmacist-driven antimicrobial optimization in the emergency department.

PubMed

Davis, Lucretia C; Covey, Robin B; Weston, Jaye S; Hu, Bee Bee Y; Laine, Gregory A

2016-03-01

A pharmacist-driven antimicrobial optimization service in the non-trauma emergency department (ED) of an 864-bed non-profit tertiary care teaching hospital was reviewed to assess its value. Local antimicrobial resistance patterns of urine, wound, stool, and blood cultures were also studied to determine whether or not empiric prescribing practices should be modified. A retrospective electronic chart review was performed for ED patients with positive cultures during two different three-month periods. During Period 1, ED nursing management performed positive culture follow-up. During Period 2, ED clinical pharmacists performed this role. The primary objective was to determine the value of the pharmacist-driven antimicrobial optimization service as measured by the number of clinical interventions made when indicated. The secondary objective was to examine resistance patterns of urine and wound isolates in order to determine if empiric prescribing patterns in the ED should be modified. During Period 1, there were 499 patient visits with subsequent positive cultures. Of those, 76 patients (15%) were discharged home. Nursing management intervened on 21 of 42 (50%) positive cultures that required an intervention; in Period 2, there were 473 patient visits with subsequent positive cultures, and 64 (14%) were discharged home. Pharmacists intervened on 24 of 30 (80%) cultures where an intervention was indicated resulting in a 30% increase in interventions for inappropriate therapy (p = 0.01). A review of the secondary objective revealed a 38% fluoroquinolone resistance rate of E. coli, the most frequently isolated urinary organism. Pharmacist-driven antimicrobial stewardship program resulted in a 30% absolute increase in interventions for inappropriate therapy as compared to the nursing-driven model. This stewardship program has further demonstrated the value of ED pharmacists. Pharmacist interventions should help to ensure that infections are resolved through modification of antimicrobial therapies for patients with bug-drug mismatches. The fluoroquinolone resistance rate indicates a need to consider alternative therapies for uncomplicated urinary tract infections. Nitrofurantoin remains with good coverage against E. coli and Enterococcus species but should be used in uncomplicated patients with normal renal function. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Nationwide survey on the 2005 Guidelines for the Management of Community-Acquired Adult Pneumonia: validation of differentiation between bacterial pneumonia and atypical pneumonia.

PubMed

Watanabe, Akira; Goto, Hajime; Kohno, Shigeru; Matsushima, Toshiharu; Abe, Shosaku; Aoki, Nobuki; Shimokata, Kaoru; Mikasa, Keiichi; Niki, Yoshihito

2012-03-01

The Japanese Respiratory Society Guidelines for the Management of Community-Acquired Pneumonia (CAP) in Adults (JRS 2005) was published as a revision of the Basic Concept for the Management of CAP in Adults (JRS 2000). To evaluate the JRS 2005 criteria for differentiating between disease types and assessing the status of antimicrobial agent use in initial treatment, we conducted a prospective survey. The survey was conducted from July 2006 to March 2007 as a nationwide joint study by 200 institutions. The study subjects included patients aged ≥16 years of age who had CAP, and patients who met the inclusion criteria were consecutively enrolled. Disease type differentiation based on JRS 2005 and JRS 2000 was conducted. Disease type diagnosis was also performed based on test results. The sensitivity and specificity of disease type differentiation were calculated. The antimicrobial agents used in the initial treatment were classified as recommended or non-recommended based on JRS 2005. The validity of non-recommended antimicrobial agent use was investigated. A total of 1875 patients were analyzed. Differentiation of atypical pneumonia using the JRS 2005 criteria had higher sensitivity and lower specificity than differentiation using the JRS 2000 criteria. The antimicrobial agents recommended by JRS 2005 were used as initial treatment in a low number of cases. The efficacy of the recommended antimicrobial agents was similar to that of the non-recommended agents. JRS 2005 is advantageous in terms of reducing the number of items used in disease type differentiation. The recommended antimicrobial agents used for the initial treatment are believed to be appropriate. Copyright © 2012 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.

Antimicrobial Activity of Extracts of the Oyster Culinary Medicinal Mushroom Pleurotus ostreatus (Higher Basidiomycetes) and Identification of a New Antimicrobial Compound.

PubMed

Younis, Ahmed M; Wu, Fang-Sheng; El Shikh, Hussien H

2015-01-01

Pleurotus ostreatus is an edible mushroom that also has high medicinal values. In this study, P. ostreatus was tested for its ability to inhibit the growth of fungi and bacteria. The freeze-dried fruiting body, broth from submerged culture, and mycelial biomass of P. ostreatus were extracted using alcohols and water as solvents. The extracts were then tested for their antimicrobial activity against the growth of fungi and bacteria. It was observed that the water extract from fruiting bodies had the strongest effect in inhibiting the growth of most fungi. The most sensitive test microfungi to the inhibition were Candida albicans, Cryptococcus humicola, and Trichosporon cutaneum, and the most sensitive test bacteria were Staphylococcus aureus followed by Escherichia coli. Water extracts from culture broth or mycelial biomass were moderately inhibitive to the growth of fungi and bacteria. The alcohol-based solvents from all samples had much less antimicrobial activity against most test microorganisms. An antimicrobial compound was purified from the water extracts of fruiting bodies with Sephadex G 100 column chromatography and characterized by infrared absorption spectrum (IR), nuclear magnetic resonance (NMR), and mass spectroscopic analysis. We have identified this compound to be 3-(2-aminopheny1thio)-3-hydroxypropanoic acid. This purified compound had a minimum inhibitory concentration of 30 µg/mL and 20 µg/mL against the growth of fungi and bacteria, respectively.

Genotypic and Phenotypic Characterization of Antimicrobial-Resistant Escherichia coli from Farm-Raised Diarrheic Sika Deer in Northeastern China

PubMed Central

Li, Rui; He, Liang; Hao, Lili; Wang, Qi; Zhou, Yu; Jiang, Hongchen

2013-01-01

In China, overuse and/or abuse of antimicrobials are common in stockbreeding, which possess high risks of antimicrobial-resistant contaminations. The serogroups, major virulence genes, and antimicrobial resistant patterns of the antimicrobial-resistant Escherichia coli (E. coli) were investigated in the feces of diarrheic farm-raised sika deer from 50 farms in three Northeastern provinces of China. A total of 220 E. coli isolates were obtained and characterized. Twenty-eight O serogroups were identified from the obtained E. coli isolates with O2, O26, O128, O142 and O154 being dominant. Nearly all the isolates were resistant to at least four of the tested antimicrobials. More than 90% of the E. coli isolates carried at least one of the tested virulence genes. About 85% of the E. coli isolates carried one or more antimicrobial-resistant genes responsible for resistant phenotypes of sulfonamides, streptomycin/spectionomycin or tetracycline. The antimicrobial resistant level and pathogenic group occurrences of the obtained E. coli isolates were higher than that of livestock and wild animals reported in some developed countries. Thus, the fecal-carrying antimicrobial-resistant E. coli from the farm-raised sika deer is potentially a significant contamination source for freshwater systems and food chain, and may pose great health risks for human and animals in Northeastern China. PMID:24039919

Keeping track of antimicrobial resistance for Neisseria gonorrhoeae in Auckland, New Zealand: past, present and future considerations.

PubMed

McAuliffe, Gary; Smith, Marian; Brokenshire, Mike; Forster, Rose; Reid, Murray; Roberts, Sally

2018-06-22

Neisseria gonorrhoeae (NG) has developed resistance to a wide range of antimicrobials. Population level data is essential to determine empiric treatment regimes. We sought to identify antimicrobial resistance patterns for NG in the Auckland region from 2008-2016, and review the utility of current methods of antimicrobial resistance testing. Antimicrobial susceptibilities and demographic data from NG isolates derived from patients attending the Auckland Regional Sexual Health Service and Auckland City Hospital were analysed to determine resistance rates and trends over time. Antimicrobial susceptibility testing was performed by agar dilution using Clinical and Laboratory Standards Institute (CLSI) interpretation criteria. Results for 2,302 isolates from 1,941 patients were analysed. While ciprofloxacin resistance increased between 2008 and 2011, resistance rates for all antibiotics declined from 2013-2016. In 2016, 22% (53) of isolates were resistant to ciprofloxacin, 7% (17) to penicillin, 31% (76) to tetracycline and 0.8% (2) exhibited decreased susceptibility to ceftriaxone. Ceftriaxone is still suitable as a component of gonorrhoea treatment in our region but resistance to other agents prohibits their use for empiric treatment regimens. Current methods of detecting antimicrobial resistance for NG needed to be updated so that they are fit for purpose.

Bacterial isolates from equine infections in western Canada (1998–2003)

PubMed Central

Clark, Chris; Greenwood, Sarah; Boison, Joe O.; Chirino-Trejo, Manuel; Dowling, Patricia M.

2008-01-01

All bacterial samples of equine origin submitted to the diagnostic laboratory at the Western College of Veterinary Medicine from January 1998 to December 2003 from either “in-clinic” or Field Service cases were accessed (1323 submissions). The most common bacterial isolates from specific presenting signs were identified, along with their in vitro antimicrobial susceptibility patterns. The most common site from which significant bacterial isolates were recovered was the respiratory tract, followed by wounds. Streptococcus zooepidemicus was the most common isolate from most infections, followed by Escherichia coli. Antimicrobial resistance was not common in the isolates and acquired antimicrobial resistance to multiple drugs was rare. The results are compared with previous published studies from other institutions and used to suggest appropriate antimicrobial treatments for equine infections in western Canada. PMID:18309745

Clostridium difficile Infection and Patient-Specific Antimicrobial Resistance Testing Reveals a High Metronidazole Resistance Rate.

PubMed

Barkin, Jodie A; Sussman, Daniel A; Fifadara, Nimita; Barkin, Jamie S

2017-04-01

Clostridium difficile (CD) infection (CDI) causes marked morbidity and mortality, accounting for large healthcare expenditures annually. Current CDI treatment guidelines focus on clinical markers of patient severity to determine the preferred antibiotic regimen of metronidazole versus vancomycin. The antimicrobial resistance patterns for patients with CD are currently unknown. The aim of this study was to define the antimicrobial resistance patterns for CD. This study included all patients with stools sent for CD testing to a private laboratory (DRG Laboratory, Alpharetta, Georgia) in a 6-month period from across the USA. Patient data was de-identified, with only age, gender, and zip-code available per laboratory protocol. All samples underwent PCR testing followed by hybridization for CD toxin regions A and B. Only patients with CD-positive PCR were analyzed. Antimicrobial resistance testing using stool genomic DNA evaluated presence of imidazole- and vancomycin-resistant genes using multiplex PCR gene detection. Of 2743, 288 (10.5%) stool samples were positive for CD. Six were excluded per protocol. Of 282, 193 (69.4%) were women, and average age was 49.4 ± 18.7 years. Of 282, 62 were PCR positive for toxins A and B, 160 for toxin A positive alone, and 60 for toxin B positive alone. Antimicrobial resistance testing revealed 134/282 (47.5%) patients resistant to imidazole, 17 (6.1%) resistant to vancomycin, and 9 (3.2%) resistant to imidazole and vancomycin. CD-positive patients with presence of imidazole-resistant genes from stool DNA extract was a common phenomenon, while vancomycin resistance was uncommon. Similar to treatment of other infections, antimicrobial resistance testing should play a role in CDI clinical decision-making algorithms to enable more expedited and cost-effective delivery of patient care.

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

Patterns of antimicrobial resistance in Streptococcus suis isolates from pigs with or without streptococcal disease in England between 2009 and 2014.

PubMed

Hernandez-Garcia, Juan; Wang, Jinhong; Restif, Olivier; Holmes, Mark A; Mather, Alison E; Weinert, Lucy A; Wileman, Thomas M; Thomson, Jill R; Langford, Paul R; Wren, Brendan W; Rycroft, Andrew; Maskell, Duncan J; Tucker, Alexander W

2017-08-01

Antimicrobial resistance in Streptococcus suis, a global zoonotic pathogen of pigs, has been mostly studied only in diseased animals using surveys that have not evaluated changes over time. We compared patterns of resistance between S. suis isolates from clinical cases of disease (CC) and non-clinical case (NCC) pigs in England, collected over two discrete periods, 2009-2011 and 2013-2014. Minimum inhibitory concentrations (MIC) of 17 antimicrobials (nine classes) were determined on 405 S. suis isolates categorised by sampling period and disease association to assess changes in resistance over time and association with disease. First, isolates were characterized as resistant or susceptible using published clinical breakpoints. Second, epidemiological cut-offs (ECOFF) were derived from MIC values, and isolates classified as wild type (WT) below the ECOFF and non-wild type (NWT) above the ECOFF. Finally, isolate subsets were analysed for shifts in MIC distribution. NCC isolates were more resistant than CC isolates to cephalosporins, penams, pleuromutilins, potentiated sulphonamides and tetracyclines in both study periods. Resistance levels among CC isolates increased in 2013-2014 relative to 2009-2011 for antimicrobials including aminoglycosides, cephalosporins, fluoroquinolones, pleuromutilins, potentiated sulphonamides and tetracyclines. The prevalence of isolates categorised as NWT for five or more classes of antimicrobials was greater among NCC than CC isolates for both time periods, and increased with time. This study used standardised methods to identify significant shifts in antimicrobial resistance phenotypes of S. suis isolated from pigs in England, not only over time but also between isolates from known clinical cases or disease-free pigs. Copyright © 2017. Published by Elsevier B.V.

Antimicrobial resistance trends among Salmonella isolates obtained from horses in the northeastern United States (2001-2013).

PubMed

Cummings, Kevin J; Perkins, Gillian A; Khatibzadeh, Sarah M; Warnick, Lorin D; Aprea, Victor A; Altier, Craig

2016-05-01

OBJECTIVE To describe the antimicrobial resistance patterns of Salmonella isolates obtained from horses in the northeastern United States and to identify trends in resistance to select antimicrobials over time. SAMPLE 462 Salmonella isolates from horses. PROCEDURES Retrospective data were collected for all Salmonella isolates obtained from equine specimens that were submitted to the Cornell University Animal Health Diagnostic Center between January 1, 2001, and December 31, 2013. Temporal trends in the prevalence of resistant Salmonella isolates were investigated for each of 13 antimicrobials by use of the Cochran-Armitage trend test. RESULTS The prevalence of resistant isolates varied among antimicrobials and ranged from 0% (imipenem) to 51.5% (chloramphenicol). During the observation period, the prevalence of resistant isolates decreased significantly for amoxicillin-clavulanic acid, ampicillin, cefazolin, cefoxitin, ceftiofur, chloramphenicol, and tetracycline and remained negligible for amikacin and enrofloxacin. Of the 337 isolates for which the susceptibility to all 13 antimicrobials was determined, 138 (40.9%) were pansusceptible and 192 (57.0%) were multidrug resistant (resistant to ≥ 3 antimicrobial classes). The most common serovar isolated was Salmonella Newport, and although the annual prevalence of that serovar decreased significantly over time, that decrease had only a minimal effect on the observed antimicrobial resistance trends. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that current antimicrobial use in horses is not promoting the emergence and dissemination of antimicrobial-resistant Salmonella strains in the region served by the laboratory.

NORMAL VAGINAL BACTERIAL FLORA OF GIANT PANDAS (AILUROPODA MELANOLEUCA) AND THE ANTIMICROBIAL SUSCEPTIBILITY PATTERNS OF THE ISOLATES.

PubMed

Yang, Xin; Yang, Jiang; Wang, Hongning; Li, Caiwu; He, Yongguo; Jin, SenYan; Zhang, Hemin; Li, Desheng; Wang, Pengyan; Xu, Yuesong; Xu, Changwen; Fan, Chengyun; Xu, Lulai; Huang, Shan; Qu, Chunmao; Li, Guo

2016-03-01

In order to study the typical vaginal bacterial flora of giant pandas (Ailuropoda melanoleuca), we took vaginal swabs for the sake of bacterial isolation, from 24 healthy female giant pandas. A total of 203 isolates were identified, representing a total of 17 bacterial species. The most common bacteria isolated were Lactobacillus spp. (54.2%, 13 of 24), followed by Staphylococcus epidermidis (41.7%, 10 of 24) and Escherichia coli (33.3%, 8 of 24). Some opportunistic pathogenic bacteria, such as Peptostreptococcus spp., Klebsiella pneumoniae, and Proteus mirabilis, were also isolated but showed no pathology. Antimicrobial susceptibility testing of aerobic bacterial isolates was performed with disk diffusion method. Of the 152 isolates, resistance was most frequently observed with chloramphenicol (17.8%), followed by tetracycline (14.5%), ciprofloxacin (12.5%), streptomycin (11.8%), and florfenicol (11.8%), while 7.2% were multidrug resistant. This is the first report of the normal vaginal culturable bacterial flora of giant pandas, followed by the antimicrobial susceptibility patterns of the isolates.

NORMAL VAGINAL BACTERIAL FLORA OF GIANT PANDAS (AILUROPODA MELANOLEUCA) AND THE ANTIMICROBIAL SUSCEPTIBILITY PATTERNS OF THE ISOLATES.

PubMed

Yang, Xin; Yang, Jiang; Wang, Hongning; Li, Caiwu; He, Yongguo; Jin, SenYan; Zhang, Hemin; Li, Desheng; Wang, Pengyan; Xu, Yuesong; Xu, Changwen; Fan, Chengyun; Xu, Lulai; Huang, Shan; Qu, Chunmao; Li, Guo

2016-06-01

To study the typical vaginal bacterial flora of giant pandas (Ailuropoda melanoleuca), we took vaginal swabs for the sake of bacterial isolation, from 24 healthy female giant pandas. A total of 203 isolates were identified, representing a total of 17 bacterial species. The most common bacteria isolated were Lactobacillus spp. (54.2%, 13/24), followed by Staphylococcus epidermidis (41.7%, 10/24) and Escherichia coli (33.3%, 8/24). Some opportunistic pathogenic bacteria, such as Peptostreptococcus spp., Klebsiella pneumoniae , and Proteus mirabilis , were also isolated but showed no pathology. Antimicrobial susceptibility testing of aerobic bacterial isolates was performed with the disk diffusion method. Of the 152 isolates, resistance was most frequently observed with chloramphenicol (17.8%), followed by tetracycline (14.5%), ciprofloxacin (12.5%), streptomycin (11.8%), and florfenicol (11.8%), whereas 7.2% were multidrug resistant. This is the first report of the normal culturable vaginal bacterial flora of giant pandas and the antimicrobial susceptibility patterns of the isolates.

Campylobacter Antimicrobial Drug Resistance among Humans, Broiler Chickens, and Pigs, France

PubMed Central

Prouzet-Mauléon, Valérie; Kempf, Isabelle; Lehours, Philippe; Labadi, Leila; Camou, Christine; Denis, Martine; de Valk, Henriette; Desenclos, Jean-Claude; Mégraud, Francis

2007-01-01

We describe isolates from human Campylobacter infection in the French population and the isolates' antimicrobial drug resistance patterns since 1986 and compare the trends with those of isolates from broiler chickens and pigs from 1999 to 2004. Among 5,685 human Campylobacter isolates, 76.2% were C. jejuni, 17.2% C. coli, and 5.0% C. fetus. Resistance to nalidixic acid increased from 8.2% in 1990 to 26.3% in 2004 (p<10-3), and resistance to ampicillin was high over time. Nalidixic acid resistance was greater for C. coli (21.3%) than for C. jejuni (14.9%, p<10-3). C. jejuni resistance to ciprofloxacin in broilers decreased from 31.7% in 2002 to 9.0% in 2004 (p = 0.02). The patterns of resistance to quinolones and fluoroquinolones were similar between 1999 and 2004 in human and broiler isolates for C. jejuni. These results suggest a potential benefit of a regulation policy limiting use of antimicrobial drugs in food animals. PMID:17479889

Characterization and Antimicrobial Resistance of Salmonella Typhimurium Isolates from Clinically Diseased Pigs in Korea.

PubMed

Oh, Sang-Ik; Kim, Jong Wan; Chae, Myeongju; Jung, Ji-A; So, Byungjae; Kim, Bumseok; Kim, Ha-Young

2016-11-01

This study investigated the prevalence of Salmonella enterica serovar and antimicrobial resistance in Salmonella Typhimurium isolates from clinically diseased pigs collected from 2008 to 2014 in Korea. Isolates were also characterized according to the presence of antimicrobial resistance genes and pulsed-field gel electrophoresis patterns. Among 94 Salmonella isolates, 81 (86.2%) were identified as being of the Salmonella Typhimurium serotype, followed by Salmonella Derby (6 of 94, 6.4%), Salmonella 4,[5],12:i:- (4 of 94, 4.3%), Salmonella Enteritidis (2 of 94, 2.1%), and Salmonella Brandenburg (1 of 94, 1.1%). The majority of Salmonella Typhimurium isolates were resistant to tetracycline (92.6%), followed by streptomycin (88.9%) and ampicillin (80.2%). Overall, 96.3% of Salmonella Typhimurium isolates showed multidrug-resistant phenotypes and commonly harbored the resistance genes bla TEM (64.9%), flo (32.8%), aadA (55.3%), strA (58.5%), strB (58.5%), sulII (53.2%), and tetA (61.7%). The pulsed-field gel electrophoresis analysis of 45 Salmonella Typhimurium isolates from individual farms revealed 27 distinct patterns that formed one major and two minor clusters in the dendrogram analysis, suggesting that most of the isolates (91.1%) from diseased pigs were genetically related. These findings can assist veterinarians in the selection of appropriate antimicrobial agents to combat Salmonella Typhimurium infections in pigs. Furthermore, they highlight the importance of continuous surveillance of antimicrobial resistance and genetic status in Salmonella Typhimurium for the detection of emerging resistance trends.

Dissemination of newly emerged polymyxin B sensitive Vibrio cholerae O1 containing Haitian-like genetic traits in different parts of India.

PubMed

Samanta, Prosenjit; Saha, Rudra Narayan; Chowdhury, Goutam; Naha, Arindam; Sarkar, Sounak; Dutta, Shanta; Nandy, Ranjan Kumar; Okamoto, Keinosuke; Mukhopadhyay, Asish Kumar

2018-06-21

Two natural epidemic biotypes of Vibrio cholerae O1, classical and El Tor, exhibit different patterns of sensitivity against the antimicrobial peptide polymyxin B. This difference in sensitivity has been one of the major markers in biotype classification system for several decades. A recent report regarding the emergence of polymyxin B-sensitive El Tor V. cholerae O1 in Kolkata has motivated us to track the spread of the strains containing this important trait, along with Haitian-like genetic content, in different parts of India. We have collected 260 clinical V. cholerae O1 strains from 12 states in India and screened them for polymyxin B susceptibility. Genetic characterization was also performed to study the tcpA, ctxB and rtxA genotypes by allele-specific polymerase chain reaction (PCR) and nucleotide sequencing. Interestingly, 88.85 % of the isolates were found to be sensitive to polymyxin B. All of the states, with the exception of Assam, had polymyxin B-sensitive V. cholerae strains and complete replacement with this strain was found in eight of the states. However, from 2016 onwards, all the strains tested showed sensitivity to polymyxin B. Allele-specific PCR and sequencing confirmed that all strains possessed Haitian-like genetic traits. Polymyxin B-sensitive strains have begun to spread throughout India and may lead to the revision of the biotype classification. The dissemination of these new variant strains needs to be carefully monitored in different endemic populations through active holistic surveillance to understand their clinical and epidemiological consequences.

Antimicrobial proteins in human unstimulated whole saliva in relation to each other, and to measures of health status, dental plaque accumulation and composition.

PubMed

Rudney, J D; Krig, M A; Neuvar, E K; Soberay, A H; Iverson, L

1991-01-01

Saliva antimicrobial proteins may interact in a common system to influence the oral ecology. Clinical studies of antimicrobial protein action thus may require a multiple-protein approach. Multivariate statistical methods have been used to describe possible patterns of interaction for lysozyme, lactoferrin, salivary peroxidase and secretory IgA in stimulated parotid saliva. However, oral microbes are most likely to encounter antimicrobial proteins in mixed resting saliva. Relationships among levels of lysozyme, lactoferrin, salivary peroxidase, and secretory IgA therefore were investigated in whole saliva from 216 subjects, and an attempt made to relate interperson variation in those proteins to differences in health and status, and dental plaque accumulation and composition. All proteins were significantly (alpha = 0.05) correlated with each other (r = 0.38-0.52, p less than 0.001). There was only one axis of common variation among proteins, and that axis was significantly correlated (p less than 0.001) with total protein (r = 0.84) and flow rate (r = -0.56). That pattern deviated from the previous finding that proteins of acinar origin tended to vary independently from proteins of ductal origin in stimulated parotid saliva. The difference between parotid and whole saliva may reflect constitutive secretion of all proteins at low levels of stimulation. Common variation of unstimulated saliva proteins suggests that antimicrobial actions can be compared in subjects at population extremes. There were no significant associations between antimicrobial proteins in whole saliva and measures of health status or plaque accumulation. However, the proportions of Streptococcus sanguis were significantly correlated with lysozyme (r = -0.26), lactoferrin (r = -0.34), peroxidase (r = -0.30), total protein (r = -0.37), flow rate (r = 0.24) and principal-components scores (r = -0.33) in a subset of subjects (n = 85) where commercial biochemical tests were used to supplement species identification by colony morphology. Those findings may indicate that saliva antimicrobial proteins can affect the composition of dental plaque.

Resistance patterns of multidrug resistant Acinetobacter baumannii in an ICU of a tertiary care hospital, Malaysia

PubMed Central

Janahiraman, Sivakami; Aziz, Muhammad Nazri; Hoo, Fan Kee; P’ng, Hon Shen; Boo, Yang Liang; Ramachandran, Vasudevan; Shamsuddin, Ahmad Fuad

2015-01-01

Backgrounds & Objective: Antimicrobial resistance is a major health problem worldwide in hospitals. The main contributing factors are exposures to broad-spectrum antimicrobials and cross-infections. Understanding the extent and type of antimicrobial use in tertiary care hospitals will aid in developing national antimicrobial stewardship priorities. Methods: In this study, we have analyzed the antimicrobial agents’ usage for acquisition of multidrug resistant using retrospective, cross-sectional, single-centre study in a multidisciplinary ICU at tertiary care hospital. Results: Acinetobacter baumannii (ACB) was isolated in various specimens from 662 patients. From these, 136 patients who were diagnosed with Ventilator-associated pneumonia (VAP) caused by ACB were included into the study. In our study, MDR strain accounts for 51% of all VAP cases caused by ACB. The development of ACB VAP were 10.5 + 6.4 days for MDR strains compared to susceptible organism (7.8 + 4.5 days) and had significantly longer ICU stay. Conclusion: The study concludes that prudent use of antimicrobial agents is important to reduce acquisition of MDR ACB. PMID:26870101

Serovars, bacteriophage types and antimicrobial sensitivities associated with salmonellosis in dogs in the UK (1954-2012).

PubMed

Philbey, A W; Mather, H A; Gibbons, J F; Thompson, H; Taylor, D J; Coia, J E

2014-01-25

Serovars and bacteriophage (phage) types were determined for 442 isolates of Salmonella enterica from dogs in the UK submitted to the Scottish Salmonella Reference Laboratory from 1954 to 2012. The most frequent serovars were Salmonella Typhimurium (196 isolates; 44.3 per cent), Dublin (40 isolates; 9.0 per cent), Enteritidis (28 isolates; 6.3 per cent), Montevideo (19 isolates; 4.3 per cent), Virchow (10 isolates; 2.3 per cent), Heidelberg (8 isolates; 1.8 per cent) and Derby (8 isolates; 1.8 per cent), along with 55 other recognised serovars among 127 other isolates, and six incompletely classified isolates. Serovars were frequently represented by strains commonly associated with poultry, cattle or pigs and their products. Among 196 Salmonella Typhimurium isolates from dogs, the most frequent phage types (definitive types) were the multiple antimicrobial-resistant strains DT104 (62 isolates), DT204c (18 isolates) and DT193 (8 isolates), along with antimicrobial sensitive wild finch strains DT40 (13 isolates) and DT56 variant (8 isolates). Eleven of 28 isolates of Salmonella Enteritidis were phage type 4. S enterica was frequently recovered from faecal or intestinal samples of dogs with diarrhoea, although many dogs had concurrent infection with other enteric pathogens. Salmonella Dublin was recovered from the brain and/or cerebrospinal fluid of two dogs with meningoencephalitis. Salmonella Kedougou was isolated from the joint fluid of a dog with septic arthritis. Salmonella Typhimurium and Salmonella Dublin were each recovered from the vaginas of bitches that had aborted. Isolates of Salmonella Enteritidis phage types 1, 4 and 8, Salmonella Typhimurium DT104, Salmonella Dublin and Salmonella Indiana were isolated from clinically healthy dogs in households where the same strains were recovered from human beings with diarrhoea. The pattern ampicillin-chloramphenicol-spectinomycin-streptomycin-sulfamethoxazole-tetracycline (ACSpSSuT) was the most frequent resistance phenotype and was observed in 44 (13.3 per cent) of 330 isolates. Dogs in the UK are exposed to a wide variety of serovars of S enterica, sometimes associated with clinical disease, and represent a zoonotic risk.

Antimicrobial drug residues in milk and meat: causes, concerns, prevalence, regulations, tests, and test performance.

PubMed

Mitchell, J M; Griffiths, M W; McEwen, S A; McNab, W B; Yee, A J

1998-06-01

This paper presents a historical review of antimicrobial use in food animals, the causes of residues in meat and milk, the types of residues found, their regulation in Canada, tests used for their detection, and test performance parameters, with an emphasis on immunoassay techniques. The development of residue detection methods began shortly after the introduction of antimicrobials to food animal production in the late 1940s. From initial technical concerns expressed by the dairy industry to the present public health and international trade implications, there has been an ongoing need for reliable, sensitive, and economical methods for the detection of antimicrobial residues in food animal products such as milk and meat. Initially there were microbial growth inhibition tests, followed by more sensitive and specific methods based on receptor binding, immunochemical, and chromatographic principle. An understanding of basic test performance parameters and their implications is essential when choosing an analytical strategy for residue testing. While each test format has its own attributes, none test will meet all the required analytical needs. Therefore the use of a tiered or integrated system employing assays designated for screening and confirmation is necessary to ensure that foods containing violative residues are not introduced into the food chain.

Antioxidant and antimicrobial capacity of several monofloral Cuban honeys and their correlation with color, polyphenol content and other chemical compounds.

PubMed

Alvarez-Suarez, Jose M; Tulipani, Sara; Díaz, Daimy; Estevez, Yadiley; Romandini, Stefania; Giampieri, Francesca; Damiani, Elisabetta; Astolfi, Paola; Bompadre, Stefano; Battino, Maurizio

2010-01-01

Several monofloral Cuban honeys were analyzed to determine their total phenolic, flavonoid, ascorbic acid, amino acid, protein and carotenoid contents as well as their radical-scavenging activity and antimicrobial capacities. The total phenolic, flavonoid and carotenoid contents varied considerably, and the highest values were obtained for Linen vine (Govania polygama (Jack) Urb) honey, which is classified as an amber honey. The highest amino acid content was found in Morning glory (Ipomoea triloba L.) while Liven vine had the highest protein content. Similarly Linen vine honey had the highest antioxidant activity while the lowest was found in Christmas vine (Turbina corymbosa (L.) Raf). Ascorbic acid was absent. Hydroxyl radical formation was studied by EPR and spin trapping, and it was found in all honeys tested. The antimicrobial activity was screened using two Gram-positive and Gram-negative bacteria. S. aureus was the most sensitive microorganism while Pseudomonas aeruginosa presented higher minimum active dilution values. Bacillus subtilis and Escherichia coli were both moderately sensitive to honey antimicrobial activity. A correlation between radical-scavenging activity and total phenolic content was found. Correlation existed also between color vs phenolics content, vs flavonoid content or between phenolic vs flavonoid. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

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.

Antimicrobial susceptibility patterns of Shigella isolates in Foodborne Diseases Active Surveillance Network (FoodNet) sites, 2000-2010.

PubMed

Shiferaw, Beletshachew; Solghan, Suzanne; Palmer, Amanda; Joyce, Kevin; Barzilay, Ezra J; Krueger, Amy; Cieslak, Paul

2012-06-01

Treatment of shigellosis with appropriate antimicrobial agents shortens duration of illness and bacterial shedding, but resistance to commonly used agents is increasing. We describe resistance patterns among Shigella isolates in the United States with use of linked data from the Foodborne Diseases Active Surveillance Network (FoodNet) and National Antimicrobial Resistance Monitoring System (NARMS). FoodNet sites send every 20th Shigella isolate to the NARMS laboratory for susceptibility testing. During 2000-2010, the NARMS laboratory tested 1376 Shigella isolates from FoodNet sites. Of 1118 isolates (81%) linked to FoodNet, 826 (74%) were resistant to ampicillin, 649 (58%) to streptomycin, 402 (36%) to trimethoprim-sulfamethoxazole (TMP-SMX), 355 (32%) to sulfamethoxazole-sulfisoxazole, 312 (28%) to tetracycline, 19 (2%) to nalidixic acid, and 6 (0.5%) to ciprofloxacin. The proportion of Shigella isolates with resistance to TMP-SMX was 40% among white persons, 58% among Hispanic persons, and 75% among persons with a history of international travel. Resistance to at least TMP-SMX and ampicillin was present in 25% of isolate, and 5% were resistant to ampicillin, TMP-SMX, and chloramphenicol. Overall, 5% of isolates showed multidrug resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole-sulfisoxazole, and tetracycline, including 49 Shigella flexneri (33%) and 3 Shigella sonnei (0.3%) isolates. Male individuals were more likely than female individuals to be infected with a multidrug-resistant strain (7% versus 3%; P < .01). Antimicrobial resistance differed by race, ethnicity, age, travel, and species. Resistance to commonly used antibiotics is high; therefore, it is important to look at the susceptibility pattern before starting treatment.

Antimicrobial prescribing practice in UK equine veterinary practice.

PubMed

Hughes, L A; Pinchbeck, G; Callaby, R; Dawson, S; Clegg, P; Williams, N

2013-03-01

Antimicrobial use is known to select for the emergence of resistant strains of bacteria; therefore prudent use in both human and veterinary medicine is essential to preserve their efficacy. To characterise antimicrobial prescribing patterns in UK equine practice and evaluate factors associated with prescribing. A postal questionnaire including 4 clinical scenarios was sent to 740 veterinary surgeons that treat horses. Data were collected on the clinician, their practice and sources of information regarding antimicrobials and their use. Multivariable logistic regression analysis was used to ascertain factors associated with 5 outcomes; prescribing off-licence drugs; prescribing at incorrect doses; prescribing 3rd or 4th generation cephalosporins; prescribing fluoroquinolones and prescribing potentiated sulphonamides. Questionnaires were completed by 38% of veterinary surgeons who were sent questionnaires. Less than 1% of practices had antimicrobial use guidelines. Trimethoprim-sulphonamides were most commonly prescribed in each clinical scenario. Eleven percent of prescriptions were for antimicrobial drugs not licensed for use in horses in the UK. Five percent of prescriptions for licensed antimicrobials were under the recommended dose rate and 56% over the recommended dose rate. Fluoroquinolones and 3rd and 4th generation cephalosporins accounted for 1 and 3% of prescriptions, respectively. Veterinary surgeons working at referral practices were more likely to prescribe 3rd and 4th generation cephalosporins and fluoroquinolones and off-licence antimicrobials whereas those working in first-opinion practices were more likely to prescribe potentiated sulphonamides. Sources of information regarding antimicrobials also had an effect on prescribing. Prescription of antimicrobials at inappropriate doses was common even when provided with the weight of the animal. It is uncommon for UK equine veterinary practices to have guidelines for antimicrobial use. The introduction of such guidelines could lead to more prudent use of antimicrobials. © 2012 EVJ Ltd.

Viridans Group Streptococcal Infections in Children After Chemotherapy or Stem Cell Transplantation: A 10-year Review From a Tertiary Pediatric Hospital.

PubMed

Nielsen, Maryke J; Claxton, Sarah; Pizer, Barry; Lane, Steven; Cooke, Richard P D; Paulus, Stéphane; Carrol, Enitan D

2016-03-01

Viridans Group Streptococci (VGS) are associated with high mortality rates in febrile neutropenia; yet there are no recent European pediatric studies to inform antimicrobial therapy. The aim of this study was to describe the characteristics, outcome, and resistance patterns of children with VGS bacteremia (VGSB) undergoing treatment of malignancy or hematopoietic stem cell transplant. Patients aged 0 to 18 years, admitted to a tertiary pediatric hemato-oncology center with VGSB, from 2003 to 2013, were included in the study. All data were collected retrospectively from medical records. A total of 54 bacteremic episodes occurred in 46 patients. The most common underlying diagnosis was relapsed acute lymphoblastic leukemia. Streptococcus mitis was the most frequent organism. A total of 30% of isolates were resistant to penicillin and 100% sensitive to vancomycin. There were 8 episodes (14.8%) of Viridans Group Streptococcal Shock Syndrome; 6 resulted in admission to intensive care and 3 of these patients died of multiorgan failure. The potentially fatal nature of VGSB is confirmed. The high risk in relapsed acute lymphoblastic leukemia is of note. Research is needed to develop risk-stratification scores that identify children at risk of Viridans Group Streptococcal Shock Syndrome to guide empirical antimicrobial therapy in febrile neutropenia.

Viridans Group Streptococcal Infections in Children After Chemotherapy or Stem Cell Transplantation

PubMed Central

Nielsen, Maryke J.; Claxton, Sarah; Pizer, Barry; Lane, Steven; Cooke, Richard P.D.; Paulus, Stéphane; Carrol, Enitan D.

2016-01-01

Abstract Viridans Group Streptococci (VGS) are associated with high mortality rates in febrile neutropenia; yet there are no recent European pediatric studies to inform antimicrobial therapy. The aim of this study was to describe the characteristics, outcome, and resistance patterns of children with VGS bacteremia (VGSB) undergoing treatment of malignancy or hematopoietic stem cell transplant. Patients aged 0 to 18 years, admitted to a tertiary pediatric hemato-oncology center with VGSB, from 2003 to 2013, were included in the study. All data were collected retrospectively from medical records. A total of 54 bacteremic episodes occurred in 46 patients. The most common underlying diagnosis was relapsed acute lymphoblastic leukemia. Streptococcus mitis was the most frequent organism. A total of 30% of isolates were resistant to penicillin and 100% sensitive to vancomycin. There were 8 episodes (14.8%) of Viridans Group Streptococcal Shock Syndrome; 6 resulted in admission to intensive care and 3 of these patients died of multiorgan failure. The potentially fatal nature of VGSB is confirmed. The high risk in relapsed acute lymphoblastic leukemia is of note. Research is needed to develop risk-stratification scores that identify children at risk of Viridans Group Streptococcal Shock Syndrome to guide empirical antimicrobial therapy in febrile neutropenia. PMID:26945409

Surgical site infections due to rapidly growing mycobacteria in puducherry, India.

PubMed

Kannaiyan, Kavitha; Ragunathan, Latha; Sakthivel, Sulochana; Sasidar, A R; Muralidaran; Venkatachalam, G K

2015-03-01

Rapidly growing Mycobacteria are increasingly recognized, nowadays as an important pathogen that can cause wide range of clinical syndromes in humans. We herein describe unrelated cases of surgical site infection caused by Rapidly growing Mycobacteria (RGM), seen during a period of 12 months. Nineteen patients underwent operations by different surgical teams located in diverse sections of Tamil Nadu, Pondicherry, Karnataka, India. All patients presented with painful, draining subcutaneous nodules at the infection sites. Purulent material specimens were sent to the microbiology laboratory. Gram stain and Ziehl-Neelsen staining methods were used for direct examination. Culture media included blood agar, chocolate agar, MacConkey agar, Sabourauds agar and Lowenstein-Jensen medium for Mycobacteria. Isolated microorganisms were identified and further tested for antimicrobial susceptibility by standard microbiologic procedures. Mycobacterium fortuitum and M.chelonae were isolated from the purulent drainage obtained from wounds by routine microbiological techniques from all the specimens. All isolates analyzed for antimicrobial susceptibility pattern were sensitive to clarithromycin, linezolid and amikacin but were variable to ciprofloxacin, rifampicin and tobramycin. Our case series highlights that a high level of clinical suspicion should be maintained for patients presenting with protracted soft tissue lesions with a history of trauma or surgery as these infections not only cause physical but also emotional distress that affects both the patients and the surgeon.

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.

Identification and Antimicrobial Susceptibility Testing of Anaerobic Bacteria: Rubik’s Cube of Clinical Microbiology?

PubMed Central

Gajdács, Márió; Spengler, Gabriella; Urbán, Edit

2017-01-01

Anaerobic bacteria have pivotal roles in the microbiota of humans and they are significant infectious agents involved in many pathological processes, both in immunocompetent and immunocompromised individuals. Their isolation, cultivation and correct identification differs significantly from the workup of aerobic species, although the use of new technologies (e.g., matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, whole genome sequencing) changed anaerobic diagnostics dramatically. In the past, antimicrobial susceptibility of these microorganisms showed predictable patterns and empirical therapy could be safely administered but recently a steady and clear increase in the resistance for several important drugs (β-lactams, clindamycin) has been observed worldwide. For this reason, antimicrobial susceptibility testing of anaerobic isolates for surveillance purposes or otherwise is of paramount importance but the availability of these testing methods is usually limited. In this present review, our aim was to give an overview of the methods currently available for the identification (using phenotypic characteristics, biochemical testing, gas-liquid chromatography, MALDI-TOF MS and WGS) and antimicrobial susceptibility testing (agar dilution, broth microdilution, disk diffusion, gradient tests, automated systems, phenotypic and molecular resistance detection techniques) of anaerobes, when should these methods be used and what are the recent developments in resistance patterns of anaerobic bacteria. PMID:29112122

Identification and Antimicrobial Susceptibility Testing of Anaerobic Bacteria: Rubik's Cube of Clinical Microbiology?

PubMed

Gajdács, Márió; Spengler, Gabriella; Urbán, Edit

2017-11-07

Anaerobic bacteria have pivotal roles in the microbiota of humans and they are significant infectious agents involved in many pathological processes, both in immunocompetent and immunocompromised individuals. Their isolation, cultivation and correct identification differs significantly from the workup of aerobic species, although the use of new technologies (e.g., matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, whole genome sequencing) changed anaerobic diagnostics dramatically. In the past, antimicrobial susceptibility of these microorganisms showed predictable patterns and empirical therapy could be safely administered but recently a steady and clear increase in the resistance for several important drugs (β-lactams, clindamycin) has been observed worldwide. For this reason, antimicrobial susceptibility testing of anaerobic isolates for surveillance purposes or otherwise is of paramount importance but the availability of these testing methods is usually limited. In this present review, our aim was to give an overview of the methods currently available for the identification (using phenotypic characteristics, biochemical testing, gas-liquid chromatography, MALDI-TOF MS and WGS) and antimicrobial susceptibility testing (agar dilution, broth microdilution, disk diffusion, gradient tests, automated systems, phenotypic and molecular resistance detection techniques) of anaerobes, when should these methods be used and what are the recent developments in resistance patterns of anaerobic bacteria.

Antimicrobial activity of methanolic extracts of Sambucus ebulus and Urtica dioica against clinical isolates of methicillin resistant Staphylococcus aureus.

PubMed

Salehzadeh, Ali; Asadpour, Leila; Naeemi, Akram Sadat; Houshmand, Elham

2014-01-01

Increase in the emergence of drug -resistant pathogens led to the development of natural antimicrobials. In this study the antimicrobial effect of methanolic extracts of Sambucus ebulus and Urtica dioica on 16 skin and wound infections isolates of methicillin resistant S. aureus have been studied. Solvent extraction procedure was done using soxhlet apparatus for extracting antimicrobial agents from freeze dried plants. Antibacterial activity was measured using agar well diffusion method. The MIC of Sambucus ebulus and Urtica dioica extracts against the standard strain of S. aureus ATCC 6538 were determined using the micro dilution method at 15 mg and 20 mg respectively. All the test bacteria were found sensitive to the Sambucus ebulus extract and only one isolate was resistant to Urtica dioica extract. Extracts of Sambucus ebulus and Urtica dioica possess antibacterial potency against MRSA isolates and may be used as a natural antiseptics and antimicrobial agents in medicine.

Antimicrobial effect of 7-O-butylnaringenin, a novel flavonoid, and various natural flavonoids against Helicobacter pylori strains.

PubMed

Moon, Sun Hee; Lee, Jae Hoon; Kim, Kee-Tae; Park, Yong-Sun; Nah, Seung-Yeol; Ahn, Dong Uk; Paik, Hyun-Dong

2013-10-28

The antimicrobial effect of a novel flavonoid (7-O-butylnaringenin) on Helicobacter pylori 26695, 51, and SS1 strains and its inhibitory effect on the urease activity of the strains were evaluated and compared with those of several natural flavonoids. First, various flavonoids were screened for antimicrobial activities using the paper disc diffusion method. Hesperetin and naringenin showed the strongest antimicrobial effects among the natural flavonoids tested, and thus hesperetin and naringenin were selected for comparison with 7-O-butylnaringenin. The antimicrobial effect of 7-O-butylnaringenin was greater than that of the hesperetin and naringenin. H. pylori 51 was more sensitive to 7-O-butylnaringenin (2 log reduction of colony forming units, p < 0.05) than the other two strains at 200 μM. 7-O-Butylnaringenin also showed the highest inhibitory effect against urease activity of H. pylori. Morphological changes of H. pylori 26695 treated with these flavonoids indicated that both hesperetin and 7-O-butylnaringenin at 200 μM damaged the cell membranes.

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.

Antimicrobials used for surgical prophylaxis by equine veterinary practitioners in Australia.

PubMed

Hardefeldt, L Y; Browning, G F; Thursky, K; Gilkerson, J R; Billman-Jacobe, H; Stevenson, M A; Bailey, K E

2018-01-01

Antimicrobials are widely used in Australian veterinary practices, but no investigation into the classes of antimicrobials used, or the appropriateness of use in horses, has been conducted. The aim of the study was to describe antimicrobial use for surgical prophylaxis in equine practice in Australia. Cross-sectional questionnaire survey. An online questionnaire was used to document antimicrobial usage patterns. Information solicited in the questionnaire included demographic details of the respondents, the frequency with which antimicrobials were used for specific surgical conditions (including the dose, timing and duration of therapy) and practice antimicrobial use policies and sources of information about antimicrobials and their uses. A total of 337 members of the Australian veterinary profession completed the survey. Generally, the choice of antimicrobial was appropriate for the specified equine surgical condition, but the dose and duration of therapy varied greatly. While there was poor optimal compliance with British Equine Veterinary Association guidelines in all scenarios (range 1-15%), except removal of a nonulcerated dermal mass (42%), suboptimal compliance (compliant antimicrobial drug selection but inappropriate timing, dose or duration of therapy) was moderate for all scenarios (range 48-68%), except for an uninfected contaminated wound over the thorax, where both optimal and suboptimal compliance was very poor (1%). Veterinarians practicing at a university hospital had higher odds of compliance than general practice veterinarians (Odds ratio 3.2, 95% CI, 1.1-8.9, P = 0.03). Many survey responses were collected at conferences which may introduce selection bias, as veterinarians attending conferences may be more likely to have been exposed to contemporary antimicrobial prescribing recommendations. Antimicrobial use guidelines need to be developed and promoted to improve the responsible use of antimicrobials in equine practice in Australia. An emphasis should be placed on antimicrobial therapy for wounds and appropriate dosing for procaine penicillin. © 2017 EVJ Ltd.

Does variation among provincial drug formulary antimicrobial listings in Canada influence prescribing rates?

PubMed

Glass-Kaastra, Shiona K; Finley, Rita; Hutchinson, Jim; Patrick, David M; Weiss, Karl; Conly, John

2014-01-01

The financial accessibility of antimicrobial drugs to the outpatient community in Canada is governed at the provincial level through formularies. Each province may choose to list particular drugs or impose restriction criteria on products in order to guide prescribing and/or curtail costs. Although changes to formularies have been shown to change patterns in the use of individual products and alter costs, no comparison has been made among the provincial antimicrobial formularies with regards to flexibility/stringency, or an assessment of how these formularies impact overall antimicrobial use in the provinces. To summarize provincial antimicrobial formularies and assess whether their relative flexibility/stringency had a statistical impact upon provincial prescription volume during a one year period. Provincial drug plan formularies were accessed and summarized for all prescribed antimicrobials in Canada during 2010. The number of general and restricted benefits for each plan was compiled by antimicrobial classification. Population-adjusted prescription rates for all individual antimicrobials and by antimicrobial class were obtained from the Canadian Integrated Program for Antimicrobial Resistance Surveillance. Correlations between the number of general benefits, restricted benefits, and total benefits with the prescription rate in the provinces were assessed by Spearman rank correlation coefficients. Formularies varied considerably among the Canadian provinces. Quebec had the most flexible formulary, offering the greatest number of general benefits and fewest restrictions. In contrast, Saskatchewan's formulary displayed the lowest number of general benefits and most restrictions. Correlation analyses detected a single significant result; macrolide prescription rates decreased as the number of general macrolide benefits increased. All other rates of provincial antimicrobial prescribing and measures of flexibility/stringency revealed no significant correlations. Although antimicrobial formulary listings are used to guide prescribing rates within a province, our analysis of one year's data of the impact of the antimicrobial formulary structure did not correlate with antimicrobial prescribing rates, and other factors are likely to be at play.

Antimicrobial resistance of Enterococcus faecium strains isolated from commercial probiotic products used in cattle and swine.

PubMed

Amachawadi, Raghavendra G; Giok, Felicia; Shi, Xiaorong; Soto, Jose; Narayanan, Sanjeev K; Tokach, Mike D; Apley, Mike D; Nagaraja, T G

2018-04-03

Probiotics, an antibiotic alternative, are widely used as feed additives for performance benefits in cattle and swine production systems. Among bacterial species contained in probiotics, Enterococcus faecium is common. Antimicrobial resistance (AMR), particularly multidrug resistance, is a common trait among enterococci because of their propensity to acquire resistance and horizontally transfer AMR genes. Also, E. faecium is an opportunistic pathogen, and in the United States, it is the second most common nosocomial pathogen. There has been no published study on AMR and virulence potential in E. faecium contained in probiotic products used in cattle and swine in the United States. Therefore, our objectives were to determine phenotypic susceptibilities or resistance to antimicrobials, virulence genes (asa1, gelE, cylA, esp, and hyl) and assess genetic diversity of E. faecium isolated from commercial products. Twenty-two commercially available E. faecium-based probiotic products used in cattle (n = 13) and swine (n = 9) were procured and E. faecium was isolated and species confirmed. Antimicrobial susceptibility testing to determine minimum inhibitory concentrations was done by micro-broth dilution method using National Antimicrobial Resistance Monitoring Systems Gram-positive Sensititre panel plate (CMV3AGPF), and categorization of strains as susceptible or resistant was as per Clinical Laboratory and Standards Institute's guidelines. E. faecium strains from 7 products (3 for swine and 4 for cattle) were pan-susceptible to the 16 antimicrobials tested. Strains from 15 products (6 for swine and 9 for cattle) exhibited resistance to at least one antimicrobial and a high proportion of strains was resistant to lincomycin (10/22), followed by tetracycline (4/22), daptomycin (4/22), ciprofloxacin (4/22), kanamycin (3/22), and penicillin (2/22). Four strains were multidrug resistant, with resistant phenotypes ranging from 3 to 6 antimicrobials or class. None of the E. faecium strains were positive for any of the virulence genes tested. The clonal relationships among the 22 E. faecium strains were determined by pulsed-field gel electrophoresis (PFGE) typing. A total of 10 PFGE patterns were observed with 22 strains and a few of the strains from different probiotic products had identical (100% Dice similarity) PFGE patterns. In conclusion, the E. faecium strains in a few commercial probiotics exhibited AMR to medically-important antimicrobials, but none contained virulence genes.

Effect of Encapsulation on Antimicrobial Activity of
Herbal Extracts with Lysozyme

PubMed Central

Matouskova, Petra; Bokrova, Jitka; Benesova, Pavla

2016-01-01

Summary Resistance of microorganisms to antibiotics has increased. The use of natural components with antimicrobial properties can be of great significance to reduce this problem. The presented work is focused on the study of the effect of encapsulation of selected plant and animal antimicrobial substances (herbs, spices, lysozyme and nisin) on their activity and stability. Antimicrobial components were packaged into liposomes and polysaccharide particles (alginate, chitosan and starch). Antimicrobial activity was tested against two Gram-positive (Bacillus subtilis and Micrococcus luteus) and two Gram-negative (Escherichia coli and Serratia marcescens) bacteria. Encapsulation was successful in all types of polysaccharide particles and liposomes. The prepared particles exhibited very good long-term stability, especially in aqueous conditions. Antimicrobial activity was retained in all types of particles. Liposomes with encapsulated herb and spice extracts exhibited very good inhibitory effect against all tested bacterial strains. Most of herbal extracts had very good antimicrobial effect against the tested Gram-negative bacterial strains, while Gram-positive bacteria were more sensitive to lysozyme particles. Thus, particles with co-encapsulated herbs and lysozyme are more active against different types of bacteria, and more stable and more effective during long-term storage. Particles with encapsulated mixture of selected plant extracts and lysozyme could be used as complex antimicrobial preparation with controlled release in the production of food and food supplements, pharmaceutical and cosmetic industries. PMID:27956862

Old dog begging for new tricks – Current practices and future directions in the diagnosis of delayed antimicrobial hypersensitivity

PubMed Central

Konvinse, KC; Phillips, E; White, KD; Trubiano, JA

2016-01-01

Purpose of review Antimicrobials are a leading cause of severe T-cell-mediated adverse drug reactions (ADRs). The purpose of this review is to address the current understanding of antimicrobial cross-reactivity and the ready availability of and evidence for in vitro, in vivo and ex vivo diagnostics for T-cell-mediated ADRs. Recent findings Recent literature has evaluated the efficacy of traditional antibiotic allergy management including patch testing, skin prick testing, intradermal testing and oral challenge. While patch and intradermal testing are specific for the diagnosis of immune-mediated (IM) ADRs, they suffer from drug-specific limitations in sensitivity. The use of ex vivo diagnostics, especially ELISpot has been highlighted as a promising new approach to assigning causality. Knowledge of true rates of antimicrobial cross-reactivity aids empirical antibiotic choice in the setting of previous IM-ADRs. Summary In an era of increasing antimicrobial resistance and use of broad-spectrum antimicrobial therapy, ensuring patients are assigned the correct “allergy label” is essential. Re-exposure to implicated antimicrobials, especially in the setting of severe adverse cutaneous reaction is associated with significant morbidity and mortality. The process through which an antibiotic label gets assigned, acted on and maintained is still imprecise. Predicting T-cell-mediated ADRs via personalised approaches, including HLA-typing may pave future pathways to safer antimicrobial prescribing guidelines. PMID:27753687

Antimicrobial drug use and resistance in dogs

PubMed Central

Prescott, John F.; Hanna, W. J. Brad; Reid-Smith, Richard; Drost, Kelli

2002-01-01

Fifteen years (1984–1998) of records from a Veterinary Teaching Hospital were analyzed to determine whether antimicrobial drug resistance in coagulase-positive Staphylococcus spp. (S. aureus, S. intermedius) isolated from clinical infections in dogs has increased, and whether there has been a change in the species of bacteria isolated from urinary tract infections in dogs. In coagulase-positive Staphylococcus spp., a complex pattern showing both increases and decreases of resistance to different classes of antimicrobial drugs was observed, reflecting the changing use of different antimicrobial drug classes in the hospital over a similar period (1990–1999). In canine urinary tract infections identified from 1984 to 1998, an increase in the incidence of multiresistant Enterococcus spp. was apparent, with marginal increases also in incidence in Enterobacter spp. and in Pseudomonas aeruginosa, both of which, like Enterococcus spp., are innately antimicrobial-resistant bacteria. A survey of directors of veterinary teaching hospitals in Canada and the United States identified only 3 hospitals that had any policy on use of “last resort” antimicrobial drugs (amikacin, imipenem, vancomycin). Evidence is briefly reviewed that owners may be at risk when dogs are treated with antimicrobial drugs, as well as evidence that some resistant bacteria may be acquired by dogs as a result of antimicrobial drug use in agriculture. Based in part on gaps in our knowledge, recommendations are made on prudent use of antimicrobial drugs in companion animals, as well as on the need to develop science-based infection control programs in veterinary hospitals. PMID:11842592

Evaluation of the use of an on-farm system for bacteriologic culture of milk from cows with low-grade mastitis.

PubMed

Neeser, Nicole L; Hueston, William D; Godden, Sandra M; Bey, Russell F

2006-01-15

To determine factors associated with implementation and use of an on-farm system for bacteriologic culture of milk from cows with lowgrade mastitis, including information on how producers used the on-farm bacteriologic culture system to guide antimicrobial selection practices and the resulting impact on patterns of antimicrobial use. Retrospective cohort study. Producers of 81 dairy farms. Farms that used an on-farm system for bacteriologic culture of milk from January 2001 to July 2003 were surveyed. Over half of those producers continuing to use the on-farm culture delayed antimicrobial treatment pending results of bacteriologic culture. Most other producers initiated empirical antimicrobial treatment while bacteriologic culture results were pending. Several barriers to the use of an on-farm system were identified. Significant reductions in rates of antimicrobial use were detected when comparing antimicrobial use rates before and during use of the on-farm system. Most producers chose to treat cows with mastitis caused by gram-positive pathogens with antimicrobials, whereas treatment choices for cows with mastitis caused by gram-negative bacteria and in cases in which no growth was detected varied. Readily available results permit antimicrobial selections to be made on the basis of the causative agent of mastitis. Adoption of an on-farm system for bacteriologic culture of milk may result in significant reductions in the percentage of cows treated with antimicrobials. Decreasing antimicrobial use may have several benefits including preventing unnecessary discarding of milk, decreasing the potential for drug residues in milk, and improving treatment outcomes as a result of targeted treatments.

A combination of grapefruit seed extract and concentrated cranberry juice as a potential antimicrobial preservative for the improvement of microbiological stability of hypromellose gel.

PubMed

Bernatoniene, Jurga; Keraitė, Rasa; Masteiková, Ruta; Pavilonis, Alvydas; Savickas, Arūnas

2013-10-01

Aqueous hypromellose gels are not microbiologically stable - they show signs of microorganism growth during storage. To extend the shelf-life of the gels, antimicrobial preservatives are needed. Some substances of plant origin are known for their antimicrobial properties, and thus they may be used as an alternative to synthetic preservatives. Therefore, the aim of this study was to evaluate the microbiological stability of aqueous hypromellose gel and the effectiveness of natural substances - grapefruit seed extract (GSE), concentrated cranberry juice, and a combination thereof - on the antimicrobial protection of the gel. The evaluation of the antimicrobial activity of GSE and cranberry juice showed that their antimicrobial effects differed. Both cranberry juice and GSE inhibited the growth of the standard gram-positive and gram-negative bacteria, but the effect of GSE was significantly stronger. Candida albicans was sensitive only to GSE. For this reason, in order to affect all the microorganisms studied, either a combination of 0.7% GSE and 10% cranberry juice, or 5% GSE alone may be used. The combination of GSE and cranberry juice was effective only in acidic medium (pH being 2.5-5), while the antimicrobial effect of GSE was not dependent on the pH value.

Evaluation of the flora of northern Mexico for in vitro antimicrobial and antituberculosis activity.

PubMed

Molina-Salinas, G M; Pérez-López, A; Becerril-Montes, P; Salazar-Aranda, R; Said-Fernández, S; de Torres, N Waksman

2007-02-12

The aim of the present study was to evaluate the potential antimicrobial activity of 14 plants used in northeast México for the treatment of respiratory diseases, against drug-sensitive and drug-resistant strains of Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae type b and Mycobacterium tuberculosis. Forty-eight organic and aqueous extracts were tested against these bacterial strains using a broth microdilution test. No aqueous extracts showed antimicrobial activity, whereas most of the organic extracts presented antimicrobial activity against at least one of the drug-resistant microorganisms tested. Methanol-based extracts from the roots and leaves of Leucophyllum frutescens and ethyl ether extract from the roots of Chrysanctinia mexicana showed the greatest antimicrobial activity against the drug-resistant strain of Mycobacterium tuberculosis; the minimal inhibitory concentration (MIC) were 62.5, 125 and 62.5 microg/mL, respectively; methanol-based extract from the leaves of Cordia boissieri showed the best antimicrobial activity against the drug-resistant strain of Staphylococcus aureus (MIC 250 microg/mL); the hexane-based extract from the fruits of Schinus molle showed considerable antimicrobial activity against the drug-resistant strain of Streptococcus pneumoniae (MIC 62.5 microg/mL). This study supports that selecting plants by ethnobotanical criteria enhances the possibility of finding species with activity against resistant microorganisms.

Sensitivity analysis

MedlinePlus

... Katsikas A, Beavis KG. In vitro testing of antimicrobial agents. In: McPherson RA, Pincus MR, eds. ... Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, ...

Molecular epidemiology and antimicrobial resistance of Salmonella Typhimurium DT104 on Ontario swine farms

PubMed Central

Farzan, Abdolvahab; Friendship, Robert M.; Poppe, Cornelis; Martin, Laura; Dewey, Catherine E.; Funk, Julie

2008-01-01

This study was conducted to examine antimicrobial resistances, plasmid profiles, and pulsed-field gel electrophoresis patterns of 80 Salmonella Typhimurium (including var. Copenhagen) DT104 strains (including DT104a and DT104b) recovered from pig and environmental fecal samples on 17 swine farms in Ontario. No resistance was observed to amoxicillin/clavulanic acid, apramycin, carbadox, cephalothin, ceftriaxone, ceftiofur, cefoxitin, ciprofloxacin, nalidixic acid, trimethoprim, and tobramycin. However, the isolates exhibited resistance against 4 to 10 antimicrobials with the most frequent resistance being to sulfonamides (Su), ampicillin (A), streptomycin (S), spectinomycin (Sp), chloramphenicol (C), tetracycline (T), and florfenicol (F). Thirteen distinct resistance patterns were determined but 88% of isolates shared the typical resistance pattern “ACSpSSuT.” Twelve different plasmid profiles were observed; the 62 MDa virulence-associated plasmid was detected in 95% of the isolates. The 2.1 MDa plasmid was the second most frequent one, which was harbored by 65% isolates. The isolates were classified into 23 distinct genotypes by PFGE-SpeI + BlnI when difference in at least one fragment was defined as a distinct genotype. In total, 39 distinct “types” were observed when defining a “type” based on the combination of antimicrobial resistance, plasmid pattern, and PFGE-SpeI + BlnI for each isolate. The highest diversity was 0.96 (95% CI: 0.92, 0.96) for the “type” described above followed by 0.92 (95% CI: 0.88, 0.93) for PFGE-SpeI + BlnI. The diversity of DT104 isolates indicates there might be multiple sources for this microorganism on swine farms. This knowledge might be used to track these sources, as well as to study the extent of human salmonellosis attributed to pork compared to food products derived from other food-producing animals. PMID:18505209

Evaluation of antimicrobial susceptibilities and virulence factors of Staphylococcus aureus strains isolated from community-acquired and health-care associated pediatric infections.

PubMed

Karbuz, Adem; Karahan, Zeynep Ceren; Aldemir-Kocabaş, Bilge; Tekeli, Alper; Özdemir, Halil; Güriz, Haluk; Gökdemir, Refik; İnce, Erdal; Çiftçi, Ergin

2017-01-01

Karbuz A, Karahan ZC, Aldemir-Kocabaş B, Tekeli A, Özdemir H, Güriz H, Gökdemir R, İnce E, Çiftçi E. Evaluation of antimicrobial susceptibilities and virulence factors of Staphylococcus aureus strains isolated from community-acquired and health-care associated pediatric infections. Turk J Pediatr 2017; 59: 395-403. The aim of this study was to investigate the enterotoxins and Panton-Valentine leukocidin (PVL) gene as virulence factor, identification if antimicrobial sensitivity patterns, agr (accessory gene regulator) types and sequence types and in resistant cases to obtain SCCmec (staphylococcal cassette chromosome mec) gene types which will be helpful to decide empirical therapy and future health politics for S. aureus species. Total of 150 isolates of S. aureus were isolated from the cultures of the child patients in January 2011 and December 2012. In this study, the penicillin resistance was observed as 93.8%. PVL and mecA was detected positive in 8.7% and in 6% of all S. aureus strains, respectively. Two MRSA (methicillin resistant S.aureus) strains were detected as SCCmec type III and SCCmec type V and five MRSA strains were detected as SCCmec type IV. SET-I and SET-G were the most common detected enterotoxins. In both community-associated and healthcare-associated MRSA strains, agr type 1 was detected most commonly. The most common sequence types were ST737 in 13 patients than ST22 in eight patients and ST121 in six patients. This study highlights a necessity to review the cause of small changes in the structural genes in order to determine whether it is a cause or outcome; community-acquired and healthcare associated strains overlap.

Effect of postharvest UV-C treatment on the bacterial diversity of Ataulfo mangoes by PCR-DGGE, survival of E. coli and antimicrobial activity

PubMed Central

Fernández-Suárez, Rocío; Ramírez-Villatoro, Guadalupe; Díaz-Ruiz, Gloria; Eslava, Carlos; Calderón, Montserrat; Navarro-Ocaña, Arturo; Trejo-Márquez, Andrea; Wacher, Carmen

2013-01-01

Since Mexico is the second largest exporter of mangoes, its safety assurance is essential. Research in microbial ecology and knowledge of complex interactions among microbes must be better understood to achieve maximal control of pathogens. Therefore, we investigated the effect of UV-C treatments on bacterial diversity of the Ataulfo mangoes surface using PCR-DGGE analysis of variable region V3 of 16S rRNA genes, and the survival of E. coli, by plate counting. The UV-C irradiation reduced the microbial load on the surface of mangoes immediately after treatment and the structure of bacterial communities was modified during storage. We identified the key members of the bacterial communities on the surface of fruits, predominating Enterobacter genus. Genera as Lactococcus and Pantoea were only detected on the surface of non-treated (control) mangoes. This could indicate that these genera were affected by the UV-C treatment. On the other hand, the treatment did not have a significant effect on survival of E. coli. However, genera that have been recognized as antagonists against foodborne pathogens were identified in the bands patterns. Also, phenolic compounds were determined by HPLC and antimicrobial activity was assayed according to the agar diffusion method. The main phenolic compounds were chlorogenic, gallic, and caffeic acids. Mango peel methanol extracts (UV-C treated and control mangoes) showed antimicrobial activity against strains previously isolated from mango, detecting significant differences (P < 0.05) among treated and control mangoes after 4 and 12 days of storage. Ps. fluorescens and Ps. stutszeri were the most sensitive. PMID:23761788

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.

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).

Patterns of drugs prescribed for dental outpatients in Nigeria: findings and implications.

PubMed

Fadare, Joseph O; Oshikoya, Kazeem A; Obimakinde, Obitade S; Sijuade, Abayomi O; Afolayan, Jide M; Adeleke, Adeyinka A; Godman, Brian; Ojumu, Damilola O

2017-10-01

There are concerns with inappropriate prescribing of medicines among dentists especially antimicrobials. It is more concerning if this increases resistance rates. This study aimed to address this by assessing patterns of drugs prescribed for outpatients attending a hospital dental clinic in Nigeria. The findings will be used to plan future interventions, particularly around antimicrobial prescribing, where there are concerns. Medical records of patients attending the dental clinic of a leading teaching hospital in Nigeria were evaluated. Patients referred for admission, without a prescription, or prescribed medicines without a documented diagnosis were excluded. Overall, 607 prescriptions were analysed, 314 (51.7%) were for females. Periodontal and gum diseases (414; 68.1%) were the most frequent diagnoses, followed by pulpitis (49; 8.2%), and dentoalveolar abscess (43; 7.1%). A total of 1798 medicines were prescribed for all patients with a mean of 3.0 ± 0.48 medicines per prescription. Antimicrobials (1178; 65.5%) and analgesics (620; 34.5%) were the two drug classes prescribed. Ascorbic acid and vitamin B complex were prescribed for 361 (59.5%) patients. Among antimicrobials, amoxicillin (564; 95.1%) either alone or combined with clavulanic acid was the most frequently prescribed, followed by metronidazole (561; 94.6%). Brand name prescribing was also appreciably higher than WHO recommendations. Polypharmacy, brand name prescriptions, and the frequent prescription of antimicrobials were common practices at the dental clinic of this teaching hospital in Nigeria. We suggest a review of the current standard treatment guidelines in Nigeria to guide dentists on current knowledge- and evidence-based treatment of common oral diseases.

Virulence factors and resistance to antimicrobials in Listeria monocytogenes serotype 1/2c isolated from food.

PubMed

Gelbíčová, T; Pantůček, R; Karpíšková, R

2016-08-01

The aim of this study was to assess the potential risk posed to the human population by the presence of Listeria monocytogenes serotype 1/2c in food based on the characterization of virulence factors of Listeria involved in the invasion of host cells and sensitivity to antimicrobial agents. In addition to sequencing of the inlA and inlB genes, the presence of genes lapB, aut, fbpA, ami, vip and llsX was tested. A premature stop codon (PMSC) in the inlA gene was detected in all tested strains of serotype 1/2c and, concurrently, two novel PMSC mutation types were identified. However, neither PMSC in the inlB gene nor deletion of the lapB, aut, fbpA, ami and vip genes were found in any of the strains. The presence of the llsX gene was not confirmed. Even though all L. monocytogenes strains showed sensitivity to the tested antimicrobials on the basis of their phenotype, sequencing revealed the presence of IS1542 insertion in the inlA gene, indicating the possibility of sharing of mobile genetic elements associated with antimicrobial resistance among strains. Other than the presence of PMSCs in the inlA gene, no PMSC in inlB or deletion of other factors linked to the invasiveness of listeria were detected. Tested strains showed sensitivity to antibiotics used in the therapy of listeriosis. Strains of L. monocytogenes serotype 1/2c typically carry a PMSC in the inlA gene, but these strains still represent a potential threat to public health. The possibility of transfer of IS1542, associated with resistance to vancomycin, between enterococci and Listeria spp. was revealed. © 2016 The Society for Applied Microbiology.

Rapid assessment of antimicrobial resistance prevalence using a Lot Quality Assurance sampling approach.

PubMed

van Leth, Frank; den Heijer, Casper; Beerepoot, Mariëlle; Stobberingh, Ellen; Geerlings, Suzanne; Schultsz, Constance

2017-04-01

Increasing antimicrobial resistance (AMR) requires rapid surveillance tools, such as Lot Quality Assurance Sampling (LQAS). LQAS classifies AMR as high or low based on set parameters. We compared classifications with the underlying true AMR prevalence using data on 1335 Escherichia coli isolates from surveys of community-acquired urinary tract infection in women, by assessing operating curves, sensitivity and specificity. Sensitivity and specificity of any set of LQAS parameters was above 99% and between 79 and 90%, respectively. Operating curves showed high concordance of the LQAS classification with true AMR prevalence estimates. LQAS-based AMR surveillance is a feasible approach that provides timely and locally relevant estimates, and the necessary information to formulate and evaluate guidelines for empirical treatment.

The Value OF USDA VetNet to Monitor Salmonella Isolates over time

USDA-ARS?s Scientific Manuscript database

BACKGROUND: USDA VetNet commenced in March 2004 with the following objectives: determine PFGE patterns of Salmonella isolates submitted to the National Antimicrobial Resistance Monitoring System (NARMS), compare USDA VetNet and CDC PulseNet PFGE patterns, and use the comparative data for surveillanc...

Influence of fat addition on the antimicrobial activity of sodium lactate, lauric arginate and methylparaben in minced meat.

PubMed

Magrinyà, Núria; Terjung, Nino; Loeffler, Myriam; Gibis, Monika; Bou, Ricard; Weiss, Jochen

2015-12-23

A minced meat model system containing three different fat levels (0, 15, and 50 wt.%) was used to evaluate the antimicrobial efficacy of three antimicrobials with different aqueous solubilities (sodium lactate>lauric arginate (Nα-lauroyl-L-arginine ethyl ester, LAE)>methylparaben). Various concentrations of sodium lactate (20, 40, and 60 mg/g), lauric arginate (0.5, 1, 1.5, 2.0, and 2.5 mg/g) and methylparaben (0.1, 0.5, 1.0, and 2.0 mg/g) were used to evaluate the antimicrobial activity against natural meat microbiota (total aerobic mesophilic colony counts, coliform bacteria, and lactic acid bacteria). The results indicate that the three antimicrobials tested are influenced at different strengths by the changes of the fat addition of the minced meat. The antimicrobial efficacy of LAE and methylparaben is increased by a higher fat content in the meat batter, whereas for lactate no clear lactate proportionality relationship can be seen. This structure sensitivity is most strongly pronounced with lauric arginate, which we attributed to the amphiphilic character of the molecule. Copyright © 2015 Elsevier B.V. All rights reserved.

Antimicrobial activity of grapefruit seed and pulp ethanolic extract.

PubMed

Cvetnić, Zdenka; Vladimir-Knezević, Sanda

2004-09-01

Antibacterial and antifungal activity of ethanolic extract of grapefruit (Citrus paradisi Macf., Rutaceae) seed and pulp was examined against 20 bacterial and 10 yeast strains. The level of antimicrobial effects was established using an in vitro agar assay and standard broth dilution susceptibility test. The contents of 3.92% of total polyphenols and 0.11% of flavonoids were determined spectrometrically in crude ethanolic extract. The presence of flavanones naringin and hesperidin in the extract was confirmed by TLC analysis. Ethanolic extract exibited the strongest antimicrobial effect against Salmonella enteritidis (MIC 2.06%, m/V). Other tested bacteria and yeasts were sensitive to extract concentrations ranging from 4.13% to 16.50% (m/V).

Antimicrobial activity of some essential oils against oral multidrug-resistant Enterococcus faecalis in both planktonic and biofilm state

PubMed Central

Benbelaïd, Fethi; Khadir, Abdelmounaïm; Abdoune, Mohamed Amine; Bendahou, Mourad; Muselli, Alain; Costa, Jean

2014-01-01

Objective To evaluate some essential oils in treatment of intractable oral infections, principally caused by biofilm of multidrug-resistant Enterococcus faecalis (E. faecalis), such as persistent endodontic infections in which their treatment exhibits a real challenge for dentists. Methods Ten chemically analyzed essential oils by gas chromatography-mass spectrometry were evaluated for antimicrobial activity against sensitive and resistant clinical strains of E. faecalis in both planktonic and biofilm state using two methods, disk diffusion and broth micro-dilution. Results Studied essential oils showed a good antimicrobial activity and high ability in E. faecalis biofilm eradication, whether for sensitive or multidrug-resistant strains, especially those of Origanum glandulosum and Thymbra capitata with interesting minimum inhibitory concentration, biofilm inhibitory concentration, and biofilm eradication concentration values which doesn't exceed 0.063%, 0.75%, and 1.5%, respectively. Conclusions Findings of this study indicate that essential oils extracted from aromatic plants can be used in treatment of intractable oral infections, especially caused by biofilm of multidrug-resistant E. faecalis. PMID:25182948

The anatomical distribution and antimicrobial susceptibility of yeast species isolated from healthy dogs.

PubMed

Brito, Erika H S; Fontenelle, Raquel O S; Brilhante, Raimunda S N; Cordeiro, Rossana A; Monteiro, André J; Sidrim, José J C; Rocha, Marcos F G

2009-11-01

The aim of this work was to identify the predominant yeast species present at different anatomical sites in healthy dogs and to determine their in vitro antimicrobial susceptibility using a broth microdilution assay. Samples were collected from the preputial, vaginal, oral and perianal mucosae and the isolates cultured were identified according to their morphological characteristics and biochemical profile. Malassezia pachydermatis was the most commonly isolated yeast, followed by Candida parapsilosis, Candida tropicalis, Candida albicans, Saccharomyces cerevisiae and Rhodotorula spp. Minimum inhibitory concentrations of the azole derivatives ketoconazole, itraconazole and fluconazole against Candida spp. were 0.03-16 microg/mL, 0.06 to >16 microg/mL and 0.5-64 microg/mL, respectively and Candida isolates were sensitive to caspofungin and amphotericin B. Although all isolates of M. pachydermatis were sensitive to itraconazole, fluconazole, ketoconazole and amphotericin B, they were found to be resistant to caspofungin. The study has highlighted that Candida spp., M. pachydermatis, S. cerevisiae and Rhodotorula spp. are part of the normal canine surface microbiota and some of these organisms exhibit in vitro resistance to commonly used antimicrobials.

Prevalence and antimicrobial sensitivity pattern of urinary tract infection among children with cerebral palsy, Moshi, Tanzania

PubMed Central

Ryakitimbo, Amon; Philemon, Rune; Mazuguni, Festo; Msuya, Levina

2018-01-01

Background Urinary tract infection (UTI) in children with cerebral palsy (CP) is a challenging yet common clinical condition. Children with CP bare the greatest risk of contracting UTI because of their difficulties in neuromotor control which lead to delay of bladder control, causing incomplete bladder emptying and urine retention. Method This was an analytical cross-sectional study that was conducted from September 2016 to March 2017 at Comprehensive Community Based Rehabilitation in Tanzania – Moshi and Kilimanjaro Christian Medical Centre Neurological Pediatrics Outpatient Clinic. All children who met the inclusion criteria were studied. Urine samples were collected at one point by catheterization, and urine dipstick and urine culture were done. Data were analyzed using SPSS version 20. Results A total of 99 children were enrolled in the study. The median age was 4 years (3–8 years); 53.5% were aged between 2 and 4 years. More than half were male. UTI was detected in 13.1% (n=13) of the children. Five causative agents of UTI were isolated, namely Escherichia coli, Proteus mirabilis, Klebsiella pneumonia, Staphylococcus aureus, and Enterococcus faecalis. The two most common organisms, E. coli and P. mirabilis, both had low sensitivity to ampicillin and co-trimoxazole while they were sensitive to ciprofloxacin and ceftriaxone. Conclusion UTI is a common finding among children with CP. E. coli and P. mirabilis are the commonest causative agents and are sensitive to ciprofloxacin and ceftriaxone but have low sensitivity to ampicillin and co-trimoxazole. PMID:29774893

Characterization of Salmonella spp. from wastewater used for food production in Morogoro, Tanzania.

PubMed

Mhongole, Ofred J; Mdegela, Robinson H; Kusiluka, Lughano J M; Forslund, Anita; Dalsgaard, Anders

2017-03-01

Wastewater use for crop irrigation and aquaculture is commonly practiced by communities situated close to wastewater treatment ponds. The objective of this study was to characterize Salmonella spp. and their antimicrobial susceptibility patterns among isolates from wastewater and Tilapia fish. A total of 123 Salmonella spp. isolates were isolated from 52 water and 21 fish intestinal samples. Genotyping of Salmonella spp. isolates was done by Pulsed-field Gel Electrophoresis (PFGE). Antimicrobial susceptibility testing was done by the minimal inhibitory concentration (MIC) technique. A total of 123 Salmonella spp. isolates represented 13 different serovars and 22 PFGE groups. Salmonella serovars showed resistance to 8 out of 14 antimicrobials; sulfamethaxazole (94%), streptomycin (61%), tetracycline (22%), ciprofloxacin and nalidixic acid (17%), trimethoprim (11%); gentamycin and chloramphenicol (6%). Salmonella Kentucky, S. Chandans, S. Durban and S. Kiambu showed multiple antimicrobial resistance to 7, 6 and 3 antimicrobials, respectively. This study has demonstrated that wastewater at the study sites is contaminated with Salmonella spp. which are resistant to common antimicrobials used for treatment of diseases in humans. Wastewater may, therefore, contaminate pristine surface water bodies and foodstuffs including fish and irrigated crops as well as food handlers.

Antimicrobial resistance mechanisms among Campylobacter.

PubMed

Wieczorek, Kinga; Osek, Jacek

2013-01-01

Campylobacter jejuni and Campylobacter coli are recognized as the most common causative agents of bacterial gastroenteritis in the world. Humans most often become infected by ingesting contaminated food, especially undercooked chicken, but also other sources of bacteria have been described. Campylobacteriosis is normally a self-limiting disease. Antimicrobial treatment is needed only in patients with more severe disease and in those who are immunologically compromised. The most common antimicrobial agents used in the treatment of Campylobacter infections are macrolides, such as erythromycin, and fluoroquinolones, such as ciprofloxacin. Tetracyclines have been suggested as an alternative choice in the treatment of clinical campylobacteriosis but in practice are not often used. However, during the past few decades an increasing number of resistant Campylobacter isolates have developed resistance to fluoroquinolones and other antimicrobials such as macrolides, aminoglycosides, and beta-lactams. Trends in antimicrobial resistance have shown a clear correlation between use of antibiotics in the veterinary medicine and animal production and resistant isolates of Campylobacter in humans. In this review, the patterns of emerging resistance to the antimicrobial agents useful in treatment of the disease are presented and the mechanisms of resistance to these drugs in Campylobacter are discussed.

Evolution of amoxicillin/clavulanate in the treatment of adults with acute bacterial rhinosinusitis and community-acquired pneumonia in response to antimicrobial-resistance patterns.

PubMed

File, Thomas M; Benninger, Michael S; Jacobs, Michael R

2004-06-01

Current treatment guidelines for community-acquired respiratory tract infections no longer depend solely on the characteristics of the patient and the clinical syndrome, but on those of the offending pathogen, including presence and level of antimicrobial resistance. The most common respiratory tract pathogens known to cause acute bacterial rhinosinusitis (ABRS) and community-acquired pneumonia (CAP) include Streptococcus pneumoniae and Haemophilus influenzae. The prevalence of antimicrobial resistance, especially b-lactum and macrolide resistance, among S pneumoniae and H influenzae has increased dramatically during the past 2 decades, diminishing the activity of many older antimicrobials against resistant organisms. A pharmacokinetically enhanced formulation of amoxicillin/clavulanate has been developed to fulfill the need for an oral b-lactam antimicrobial that achieves a greater time that the serum drug concentration exceeds the minimum inhibitory concentration (T > MIC) of antimicrobials against pathogens than conventional formulations to improve activity against S pneumoniae with reduced susceptibility to penicillin. The b-lactamase inhibitor clavulanate allows for coverage of b-lactamase-producing pathogens, such as H influenzae and M catarrhalis. This article reviews the rationale for, and evolution of, oral amoxicillin clavulanate for ABRS and CAP

Factors influencing antimicrobial prescribing by veterinarians and usage by dairy farmers in New Zealand.

PubMed

McDougall, S; Compton, Cwr; Botha, N

2017-03-01

To determine the factors associated with the selection of antimicrobials by dairy veterinarians, and the attitudes of those veterinarians and dairy farmers to antimicrobial usage and resistance. Facilitated focus groups of dairy farmers (n=22) and an anonymous online survey of dairy cattle veterinarians (n=206 respondents) were used to determine prescribing behaviour, factors affecting prescribing of antimicrobials, and the attitudes of veterinarians and farmers to the use of antimicrobials and the risk of antimicrobial resistance (AMR). Amongst the 22 farmers, the most common primary reason for choosing an antimicrobial was veterinary advice (87%) followed by personal experience (68%). Farmers had limited knowledge or concern about the risk of AMR, particularly outside their farm, with only 47% and 26% agreeing or strongly agreeing that use of antimicrobials on their farm would increase the risk of resistance in their herd and in humans, respectively. Prescribing of antimicrobials by veterinarians was predominantly based on diagnosis (168/206; 82%), and response to previous therapy (134/206; 65%), while duration above the minimum inhibitory concentration (43/206; 21%) was also considered important. Non-clinical factors such as withholding period (52/206; 25%) and farmers' preferences (45/206; 22%) also influenced prescribing. Antimicrobial culture and susceptibility testing was not widely used, with 126/166 (76%) having culture results for less than four of the last 10 clinical mastitis cases for which they prescribed antimicrobials. Attitudes about prescribing and AMR varied with years of practice, gender and employment status. Veterinarians primarily considered technical reasons when prescribing antimicrobials. However non-technical factors did influence prescribing, in particular client feedback about perceived efficacy and perceptions of cost/benefit. Farmers stated that veterinarians were the most credible source of advice for selection of antimicrobials, but that personal experience on their farm was also important. Farmers' perception of efficacy of antimicrobials, based on clinical outcomes, is an important determinant of their preferred choice of product. Hence, where changes in on-farm use patterns are required, clear communication by veterinarians about prudent antimicrobial choice and usage will require initial education around classes of antimicrobials and risk of resistance, as well as information around assessing efficacy of antimicrobial usage. Many veterinarians are in businesses that do not have practice prescribing policies. Such policies would likely lead to more consistent and judicious use of antimicrobials.

Antimicrobial activity of the essential oil and extracts of Cordia curassavica (Boraginaceae).

PubMed

Hernandez, Tzasna; Canales, Margarita; Teran, Barbara; Avila, Olivia; Duran, Angel; Garcia, Ana Maria; Hernandez, Hector; Angeles-Lopez, Omar; Fernandez-Araiza, Mario; Avila, Guillermo

2007-04-20

In traditional Mexican medicine Cordia curassavica (Jacq) Roemer & Schultes is used to treat gastrointestinal, respiratory and dermatological disorders in Zapotitlán de las Salinas, Puebla (México). The aim of this work was to investigate antimicrobial activity of the essential oil, obtained by using Clevenger distillation apparatus, and hexane, chloroform and methanol extracts from aerial parts of Cordia curassavica. Antimicrobial activity was evaluated against 13 bacteria and five fungal strains. The oil and extracts exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria and five fungal strains. Sarcina lutea and Vibrio cholerae were the strains more sensitive to the essential oil effect (MIC=62 microg/mL) and Vibrio cholerae for the hexane extract (MIC=125 microg/mL). Rhyzoctonia solani was the strain more sensitive to the essential oil effect (IC(50)=180 microg/mL) and Trichophyton mentagrophytes for the hexane extract (IC(50)=230 microg/mL). The essential oil was examined by GC and GC-MS. A total 11 constituents representing 96.28% of the essential oil were identified: 4-methyl,4-ethenyl-3-(1-methyl ethenyl)-1-(1-methyl methanol)cyclohexane (37.34%), beta-eudesmol (19.21%), spathulenol (11.25%) and cadina 4(5), 10(14) diene (7.93%) were found to be the major components. The present study tends to confirm the use in the folk medicine of Cordia curassavica in gastrointestinal, respiratory and dermatological diseases.

Fine-Tuning the Antimicrobial Profile of Biocompatible Gold Nanoparticles by Sequential Surface Functionalization Using Polyoxometalates and Lysine

PubMed Central

Daima, Hemant K.; Selvakannan, P. R.; Shukla, Ravi; Bhargava, Suresh K.; Bansal, Vipul

2013-01-01

Antimicrobial action of nanomaterials is typically assigned to the nanomaterial composition, size and/or shape, whereas influence of complex corona stabilizing the nanoparticle surface is often neglected. We demonstrate sequential surface functionalization of tyrosine-reduced gold nanoparticles (AuNPsTyr) with polyoxometalates (POMs) and lysine to explore controlled chemical functionality-driven antimicrobial activity. Our investigations reveal that highly biocompatible gold nanoparticles can be tuned to be a strong antibacterial agent by fine-tuning their surface properties in a controllable manner. The observation from the antimicrobial studies on a gram negative bacterium Escherichia coli were further validated by investigating the anticancer properties of these step-wise surface-controlled materials against A549 human lung carcinoma cells, which showed a similar toxicity pattern. These studies highlight that the nanomaterial toxicity and biological applicability are strongly governed by their surface corona. PMID:24147146

Fine-tuning the antimicrobial profile of biocompatible gold nanoparticles by sequential surface functionalization using polyoxometalates and lysine.

PubMed

Daima, Hemant K; Selvakannan, P R; Shukla, Ravi; Bhargava, Suresh K; Bansal, Vipul

2013-01-01

Antimicrobial action of nanomaterials is typically assigned to the nanomaterial composition, size and/or shape, whereas influence of complex corona stabilizing the nanoparticle surface is often neglected. We demonstrate sequential surface functionalization of tyrosine-reduced gold nanoparticles (AuNPs(Tyr)) with polyoxometalates (POMs) and lysine to explore controlled chemical functionality-driven antimicrobial activity. Our investigations reveal that highly biocompatible gold nanoparticles can be tuned to be a strong antibacterial agent by fine-tuning their surface properties in a controllable manner. The observation from the antimicrobial studies on a gram negative bacterium Escherichia coli were further validated by investigating the anticancer properties of these step-wise surface-controlled materials against A549 human lung carcinoma cells, which showed a similar toxicity pattern. These studies highlight that the nanomaterial toxicity and biological applicability are strongly governed by their surface corona.

Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance.

PubMed

Magiorakos, A-P; Srinivasan, A; Carey, R B; Carmeli, Y; Falagas, M E; Giske, C G; Harbarth, S; Hindler, J F; Kahlmeter, G; Olsson-Liljequist, B; Paterson, D L; Rice, L B; Stelling, J; Struelens, M J; Vatopoulos, A; Weber, J T; Monnet, D L

2012-03-01

Many different definitions for multidrug-resistant (MDR), extensively drug-resistant (XDR) and pandrug-resistant (PDR) bacteria are being used in the medical literature to characterize the different patterns of resistance found in healthcare-associated, antimicrobial-resistant bacteria. A group of international experts came together through a joint initiative by the European Centre for Disease Prevention and Control (ECDC) and the Centers for Disease Control and Prevention (CDC), to create a standardized international terminology with which to describe acquired resistance profiles in Staphylococcus aureus, Enterococcus spp., Enterobacteriaceae (other than Salmonella and Shigella), Pseudomonas aeruginosa and Acinetobacter spp., all bacteria often responsible for healthcare-associated infections and prone to multidrug resistance. Epidemiologically significant antimicrobial categories were constructed for each bacterium. Lists of antimicrobial categories proposed for antimicrobial susceptibility testing were created using documents and breakpoints from the Clinical Laboratory Standards Institute (CLSI), the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and the United States Food and Drug Administration (FDA). MDR was defined as acquired non-susceptibility to at least one agent in three or more antimicrobial categories, XDR was defined as non-susceptibility to at least one agent in all but two or fewer antimicrobial categories (i.e. bacterial isolates remain susceptible to only one or two categories) and PDR was defined as non-susceptibility to all agents in all antimicrobial categories. To ensure correct application of these definitions, bacterial isolates should be tested against all or nearly all of the antimicrobial agents within the antimicrobial categories and selective reporting and suppression of results should be avoided. © 2011 European Society of Clinical Microbiology and Infectious Diseases. No claim to original US government works.

Antimicrobial susceptibility survey on bacterial agents of canine and feline urinary tract infections: Weight of the empirical treatment.

PubMed

Rampacci, Elisa; Bottinelli, Marco; Stefanetti, Valentina; Hyatt, Doreene R; Sgariglia, Elisa; Coletti, Mauro; Passamonti, Fabrizio

2018-06-01

This work characterised the antimicrobial susceptibility of uropathogens isolated from empirically treated dogs and cats. Within-household transmission of uropathogens can involve humans and companion animals. Knowledge on the prevalence and susceptibility pattern of isolates from canine and feline urine samples and the impact of prior antimicrobial treatment is important to prevent the dissemination of antimicrobial resistance. A retrospective study was conducted selecting antibiotic-treated companion animals. Urine samples were collected by cystocentesis and were submitted to an Italian diagnostic laboratory over a 2-year period (2013-2015). The antimicrobial susceptibility of the isolates was analysed both using Clinical and Laboratory Standards Institute (CLSI) guidelines and a formula to help select rational antimicrobial therapy. Gram-negative bacteria were clearly prevalent. Gentamicin had the highest impact factors. Amoxicillin/clavulanic acid and doxycycline appeared to be the most effective compounds against Gram-positive infections, whilst marbofloxacin may be a useful option against Gram-negative urinary tract infections (UTIs) as well as doxycycline and trimethoprim/sulfamethoxazole in cats and dogs, respectively. Consulting published studies, a comparable overall trend regarding bacterial species incriminated in canine and feline UTIs and their susceptibilities seems likely, despite different circumstances where the studies were conducted. Companion animals are potential reservoirs of drug-resistant uropathogens. Judicious use of antibiotics is necessary to maintain the efficacy of antimicrobials in human and veterinary medicine. Antimicrobial susceptibility monitoring programmes are therefore essential to facilitate the choice of antimicrobial agent that is most likely to be effective, particularly in cases of prior antimicrobial treatment. Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. All rights reserved.

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.

Use of large-scale veterinary data for the investigation of antimicrobial prescribing practices in equine medicine.

PubMed

Welsh, C E; Parkin, T D H; Marshall, J F

2017-07-01

As antimicrobial resistant bacterial strains continue to emerge and spread in human and animal populations, understanding prescription practices is key in benchmarking current performance and setting goals. Antimicrobial prescription (AP) in companion veterinary species is widespread, but is neither monitored nor restricted in the USA and Canada. The veterinary use of certain antimicrobial classes is discouraged in some countries, in the hope of preserving efficacy for serious human infections. The aim of this study was to ascertain the rate of prescription of a number of 'reserved' antimicrobials in a first-opinion US and Canadian horse cohort, and identify trends in their empirical use. Retrospective cohort study. A large convenience sample of electronic medical records (2006-2012) was interrogated using text mining to identify enrofloxacin, clarithromycin and ceftiofur prescriptions. Time series analysis and logistic regression were used to identify trends and risk factors for prescription. Prescription of these antimicrobials as a first-line intervention, without culture and sensitivity testing (CST), was common in this population. Enrofloxacin prescriptions were found to increase over the study period, and there was evidence of either a reducing, or static trend in the proportion of reserved APs informed by CST. Dose adequacy could not be included due to the nature of the data used. Empirical use of reserved antimicrobials was common in this population, and further advice and guidance should be issued to first-opinion veterinarians to safeguard antimicrobial efficacy. © 2016 EVJ Ltd.

Antimicrobial prescribing behaviour in dogs and cats by Belgian veterinarians.

PubMed

Van Cleven, Alexia; Sarrazin, Steven; de Rooster, Hilde; Paepe, Dominique; Van der Meeren, Sofie; Dewulf, Jeroen

2018-03-17

The objective of this study is to survey general prescribing behaviour by Belgian companion animal veterinarians and to assess agreement of these practices with current treatment guidelines. Therefore an online survey was administered with five realistic and frequently occurring first-line cases to primary-care veterinary practitioners. For each case a predefined pattern of questions were asked about whether or not they would prescribe antimicrobials, if they would prescribe a non-antimicrobial treatment and if they would perform additional diagnostic steps. The responses were compared with recommendations in national guidelines and recent literature. The overall most prescribed antimicrobials were potentiated amoxicillin (43.0 per cent), fluoroquinolones (14.7 per cent), third-generation and fourth-generation cephalosporins (10.9 per cent) and tetracyclines (10.9 per cent). Only 48.3 per cent of the veterinarians complied with the guidelines in nearly all of the clinical scenarios (ie, prescribing antimicrobials when indicated, not prescribing antimicrobials when it is not indicated). Moreover, when prescribing highest priority critically important antimicrobials, susceptibility testing on bacterial cultures was performed in only 12.4 per cent of the prescriptions. The results showed that the prescribing behaviour of antimicrobial compounds by primary-care veterinary practitioners in dogs and cats is often not in agreement with national guidelines. Focus in improvement of this prescribing behaviour should be on performing the appropriate diagnostic steps and decreasing the use of highest priority critically important antimicrobials. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Multifaceted defense against antagonistic microbes in developing offspring of the parasitoid wasp Ampulex compressa (Hymenoptera, Ampulicidae).

PubMed

Weiss, Katharina; Parzefall, Christopher; Herzner, Gudrun

2014-01-01

Effective antimicrobial strategies are essential adaptations of insects to protect themselves, their offspring, and their foods from microbial pathogens and decomposers. Larvae of the emerald cockroach wasp, Ampulex compressa, sanitize their cockroach hosts, Periplaneta americana, with a cocktail of nine antimicrobials comprising mainly (R)-(-)-mellein and micromolide. The blend of these antimicrobials has broad-spectrum antimicrobial activity. Here we explore the spatio-temporal pattern of deployment of antimicrobials during the development from egg to adult as well as their physico-chemical properties to assess how these aspects may contribute to the success of the antimicrobial strategy. Using gas chromatography/mass spectrometry (GC/MS) we show that larvae start sanitizing their food as soon as they have entered their host to feed on its tissue. Subsequently, they impregnate the cockroach carcass with antimicrobials to create a hygienic substrate for cocoon spinning inside the host. Finally, the antimicrobials are incorporated into the cocoon. The antimicrobial profiles on cockroach and wasp cocoon differed markedly. While micromolide persisted on the cockroaches until emergence of the wasps, solid-phase microextraction sampling and GC/MS analysis revealed that (R)-(-)-mellein vaporized from the cockroaches and accumulated in the enclosed nest. In microbial challenge assays (R)-(-)-mellein in the headspace of parasitized cockroaches inhibited growth of entomopathogenic and opportunistic microbes (Serratia marcescens, Aspergillus sydowii, Metarhizium brunneum). We conclude that, in addition to food sanitation, A. compressa larvae enclose themselves in two defensive walls by impregnating the cocoon and the cockroach cuticle with antimicrobials. On top of that, they use vaporous (R)-(-)-mellein to sanitize the nest by fumigation. This multifaceted antimicrobial defense strategy involving the spatially and temporally coordinated deployment of several antimicrobials in solution and vapor form has apparently evolved to reliably protect the larvae themselves and their food against a broad range of antagonistic microbes.

Multifaceted Defense against Antagonistic Microbes in Developing Offspring of the Parasitoid Wasp Ampulex compressa (Hymenoptera, Ampulicidae)

PubMed Central

Weiss, Katharina; Parzefall, Christopher; Herzner, Gudrun

2014-01-01

Effective antimicrobial strategies are essential adaptations of insects to protect themselves, their offspring, and their foods from microbial pathogens and decomposers. Larvae of the emerald cockroach wasp, Ampulex compressa, sanitize their cockroach hosts, Periplaneta americana, with a cocktail of nine antimicrobials comprising mainly (R)-(-)-mellein and micromolide. The blend of these antimicrobials has broad-spectrum antimicrobial activity. Here we explore the spatio-temporal pattern of deployment of antimicrobials during the development from egg to adult as well as their physico-chemical properties to assess how these aspects may contribute to the success of the antimicrobial strategy. Using gas chromatography/mass spectrometry (GC/MS) we show that larvae start sanitizing their food as soon as they have entered their host to feed on its tissue. Subsequently, they impregnate the cockroach carcass with antimicrobials to create a hygienic substrate for cocoon spinning inside the host. Finally, the antimicrobials are incorporated into the cocoon. The antimicrobial profiles on cockroach and wasp cocoon differed markedly. While micromolide persisted on the cockroaches until emergence of the wasps, solid-phase microextraction sampling and GC/MS analysis revealed that (R)-(-)-mellein vaporized from the cockroaches and accumulated in the enclosed nest. In microbial challenge assays (R)-(-)-mellein in the headspace of parasitized cockroaches inhibited growth of entomopathogenic and opportunistic microbes (Serratia marcescens, Aspergillus sydowii, Metarhizium brunneum). We conclude that, in addition to food sanitation, A. compressa larvae enclose themselves in two defensive walls by impregnating the cocoon and the cockroach cuticle with antimicrobials. On top of that, they use vaporous (R)-(-)-mellein to sanitize the nest by fumigation. This multifaceted antimicrobial defense strategy involving the spatially and temporally coordinated deployment of several antimicrobials in solution and vapor form has apparently evolved to reliably protect the larvae themselves and their food against a broad range of antagonistic microbes. PMID:24886721

Antimicrobial Effect of 7-O-Butylnaringenin, a Novel Flavonoid, and Various Natural Flavonoids against Helicobacter pylori Strains

PubMed Central

Moon, Sun Hee; Lee, Jae Hoon; Kim, Kee-Tae; Park, Yong-Sun; Nah, Seung-Yeol; Ahn, Dong Uk; Paik, Hyun-Dong

2013-01-01

The antimicrobial effect of a novel flavonoid (7-O-butylnaringenin) on Helicobacter pylori 26695, 51, and SS1 strains and its inhibitory effect on the urease activity of the strains were evaluated and compared with those of several natural flavonoids. First, various flavonoids were screened for antimicrobial activities using the paper disc diffusion method. Hesperetin and naringenin showed the strongest antimicrobial effects among the natural flavonoids tested, and thus hesperetin and naringenin were selected for comparison with 7-O-butylnaringenin. The antimicrobial effect of 7-O-butylnaringenin was greater than that of the hesperetin and naringenin. H. pylori 51 was more sensitive to 7-O-butylnaringenin (2 log reduction of colony forming units, p < 0.05) than the other two strains at 200 μM. 7-O-Butylnaringenin also showed the highest inhibitory effect against urease activity of H. pylori. Morphological changes of H. pylori 26695 treated with these flavonoids indicated that both hesperetin and 7-O-butylnaringenin at 200 μM damaged the cell membranes. PMID:24169409

Antibacterial activity of peritoneal exudate in patients treated with 2 g cefotiam for surgical anti-microbial prophylaxis.

PubMed

Miglioli, P A; Schoeffel, U; Gabroska, E; Allerberger, F

1998-01-01

The objective of this study was to investigate the presence of antibacterial activity in peritoneal exudate (PE) of patients treated with cefotiam (CFT). CFT (2 g) was administered as a 'single-shot' antimicrobial prophylaxis to 6 patients at the beginning of colorectal resection. Samples of PE were collected from each patient on days 1, 2 and 3 after surgery. CFT was detectable in the samples of day 1 for 5 of the 6 patients. The influence of PE on antibacterial activity of the antimicrobial drug was evaluated carrying out the MICs of CFT against Escherichia coli K-12, E. coli (ATCC 10798), Klebsiella pneumoniae (ATCC 1003), Proteus rettgeri (Sanelli) and Staphylococcus aureus (ATCC 29213) with and without the addition of PE. The presence of PE enhanced the antimicrobial activity of CFT against gram-negative strains, but not against S. aureus (ATCC 29213). These results suggest the presence of substances in PE that possess endogenous antibacterial activity. Thus, antimicrobial activity in PE cannot be predicted by evaluating pathogen sensitivity in vitro only.

Conformational study of melectin and antapin antimicrobial peptides in model membrane environments

NASA Astrophysics Data System (ADS)

Kocourková, Lucie; Novotná, Pavlína; Čujová, Sabína; Čeřovský, Václav; Urbanová, Marie; Setnička, Vladimír

2017-01-01

Antimicrobial peptides have long been considered as promising compounds against drug-resistant pathogens. In this work, we studied the secondary structure of antimicrobial peptides melectin and antapin using electronic (ECD) and vibrational circular dichroism (VCD) spectroscopies that are sensitive to peptide secondary structures. The results from quantitative ECD spectral evaluation by Dichroweb and CDNN program and from the qualitative evaluation of the VCD spectra were compared. The antimicrobial activity of the selected peptides depends on their ability to adopt an amphipathic α-helical conformation on the surface of the bacterial membrane. Hence, solutions of different zwitterionic and negatively charged liposomes and micelles were used to mimic the eukaryotic and bacterial biological membranes. The results show a significant content of α-helical conformation in the solutions of negatively charged liposomes mimicking the bacterial membrane, thus correlating with the antimicrobial activity of the studied peptides. On the other hand in the solutions of zwitterionic liposomes used as models of the eukaryotic membranes, the fraction of α-helical conformation was lower, which corresponds with their moderate hemolytic activity.

Distinct fermentation and antibiotic sensitivity profiles exist in salmonellae of canine and human origin.

PubMed

Wallis, Corrin V; Lowden, Preena; Marshall-Jones, Zoe V; Hilton, Anthony C

2018-02-26

Salmonella enterica is a recognised cause of diarrhoea in dogs and humans, yet the potential for transfer of salmonellosis between dogs and their owners is unclear, with reported evidence both for and against Salmonella as a zoonotic pathogen. A collection of 174 S. enterica isolates from clinical infections in humans and dogs were analysed for serotype distribution, carbon source utilisation, chemical and antimicrobial sensitivity profiles. The aim of the study was to understand the degree of conservation in phenotypic characteristics of isolates across host species. Serovar distribution across human and canine isolates demonstrated nine serovars common to both host species, 24 serovars present in only the canine collection and 39 solely represented within the human collection. Significant differences in carbon source utilisation profiles and ampicillin, amoxicillin and chloramphenicol sensitivity profiles were detected in isolates of human and canine origin. Differences between the human and canine Salmonella collections were suggestive of evolutionary separation, with canine isolates better able to utilise several simple sugars than their human counterparts. Generally higher minimum inhibitory concentrations of three broad-spectrum antimicrobials, commonly used in veterinary medicine, were also observed in canine S. enterica isolates. Differential carbon source utilisation and antimicrobial sensitivity profiles in pathogenic Salmonella isolated from humans and dogs are suggestive of distinct reservoirs of infection for these hosts. Although these findings do not preclude zoonotic or anthroponotic potential in salmonellae, the separation of carbon utilisation and antibiotic profiles with isolate source is indicative that infectious isolates are not part of a common reservoir shared frequently between these host species.

Antimicrobial resistance patterns of bovine Salmonella enterica isolates submitted to the Wisconsin Veterinary Diagnostic Laboratory: 2006-2015.

PubMed

Valenzuela, J R; Sethi, A K; Aulik, N A; Poulsen, K P

2017-02-01

Salmonellosis on the dairy continues to have a significant effect on animal health and productivity and in the United States. Additionally, Salmonella enterica ssp. enterica causes an estimated 1.2 million cases of human illness annually. Contributing to the morbidity and mortality in both human and domestic animal species is emergence of antimicrobial resistance by Salmonella species and increased incidence of multidrug-resistant isolates. This study describes serotype distribution and the antimicrobial resistance patterns for various Salmonella serotypes isolated from bovine samples submitted to the Wisconsin Veterinary Diagnostic Laboratory (WVDL) over the past 10 yr. Salmonella serotyping and antimicrobial susceptibility testing data were obtained from the laboratory information management system at WVDL. Data from accessions were limited to bovine samples submitted to the WVDL between January 2006 and June 2015 and those that had both a definitive serotype and complete results for antimicrobial susceptibility testing. A total of 4,976 isolates were identified. Salmonella enterica ser. Dublin was the most prevalent serotype identified among bovine samples submitted to the WVDL, accounting for a total of 1,153 isolates (23% of total isolates) over the study period. Along with Dublin, Salmonella enterica ser. Cerro (795, 16%), Newport (720, 14%), Montevideo (421, 8%), Kentucky (419, 8%), and Typhimurium (202, 4%) comprised the top 6 most commonly isolated serotypes during that time. Overall, resistance of bovine Salmonella isolates in the study population remained stable, although decreases in resistance were noted for gentamicin, neomycin, and trimethoprim sulfamethoxazole during the study period. All isolates remained susceptible to enrofloxacin. These data show that antimicrobial susceptibility for bovine Salmonella has changed in the population served by WVDL in the past 10 yr. This information is important for understanding Salmonella disease ecology in Wisconsin. Our findings are also relevant for animal and public health by improving informed antimicrobial use, new drug development, and regulation of their use in food animals. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

Antimicrobial consumption, costs and resistance patterns: a two year prospective study in a Romanian intensive care unit.

PubMed

Axente, Carmen; Licker, Monica; Moldovan, Roxana; Hogea, Elena; Muntean, Delia; Horhat, Florin; Bedreag, Ovidiu; Sandesc, Dorel; Papurica, Marius; Dugaesescu, Dorina; Voicu, Mirela; Baditoiu, Luminita

2017-05-22

Due to the vulnerable nature of its patients, the wide use of invasive devices and broad-spectrum antimicrobials used, the intensive care unit (ICU) is often called the epicentre of infections. In the present study, we quantified the burden of hospital acquired pathology in a Romanian university hospital ICU, represented by antimicrobial agents consumption, costs and local resistance patterns, in order to identify multimodal interventional strategies. Between 1 st January 2012 and 31 st December 2013, a prospective study was conducted in the largest ICU of Western Romania. The study group was divided into four sub-samples: patients who only received prophylactic antibiotherapy, those with community-acquired infections, patients who developed hospital acquired infections and patients with community acquired infections complicated by hospital-acquired infections. The statistical analysis was performed using the EpiInfo version 3.5.4 and SPSS version 20. A total of 1596 subjects were enrolled in the study and the recorded consumption of antimicrobial agents was 1172.40 DDD/ 1000 patient-days. The presence of hospital acquired infections doubled the length of stay (6.70 days for patients with community-acquired infections versus 16.06/14.08 days for those with hospital-acquired infections), the number of antimicrobial treatment days (5.47 in sub-sample II versus 11.18/12.13 in sub-samples III/IV) and they increased by 4 times compared to uninfected patients. The perioperative prophylactic antibiotic treatment had an average length duration of 2.78 while the empirical antimicrobial therapy was 3.96 days in sample II and 4.75/4.85 days for the patients with hospital-acquired infections. The incidence density of resistant strains was 8.27/1000 patient-days for methicilin resistant Staphylococcus aureus, 7.88 for extended spectrum β-lactamase producing Klebsiella pneumoniae and 4.68/1000 patient-days for multidrug resistant Acinetobacter baumannii. Some of the most important circumstances collectively contributing to increasing the consumption of antimicrobials and high incidence densities of multidrug-resistant bacteria in the studied ICU, are represented by prolonged chemoprophylaxis and empirical treatment and also by not applying the definitive antimicrobial therapy, especially in patients with favourable evolution under empirical antibiotic treatment. The present data should represent convincing evidence for policy changes in the antibiotic therapy.

Antimicrobial resistance patterns of Staphylococcus species isolated from cats presented at a veterinary academic hospital in South Africa.

PubMed

Qekwana, Daniel Nenene; Sebola, Dikeledi; Oguttu, James Wabwire; Odoi, Agricola

2017-09-15

Antimicrobial resistance is becoming increasingly important in both human and veterinary medicine. This study investigated the proportion of antimicrobial resistant samples and resistance patterns of Staphylococcus isolates from cats presented at a veterinary teaching hospital in South Africa. Records of 216 samples from cats that were submitted to the bacteriology laboratory of the University of Pretoria academic veterinary hospital between 2007 and 2012 were evaluated. Isolates were subjected to antimicrobial susceptibility testing against a panel of 15 drugs using the disc diffusion method. Chi square and Fisher's exact tests were used to assess simple associations between antimicrobial resistance and age group, sex, breed and specimen type. Additionally, associations between Staphylococcus infection and age group, breed, sex and specimen type were assessed using logistic regression. Staphylococcus spp. isolates were identified in 17.6% (38/216) of the samples submitted and 4.6% (10/216) of these were unspeciated. The majority (61.1%,11/18) of the isolates were from skin samples, followed by otitis media (34.5%, 10/29). Coagulase Positive Staphylococcus (CoPS) comprised 11.1% (24/216) of the samples of which 7.9% (17/216) were S. intermedius group and 3.2% (7/216) were S. aureus. Among the Coagulase Negative Staphylococcus (CoNS) (1.9%, 4/216), S. felis and S. simulans each constituted 0.9% (2/216). There was a significant association between Staphylococcus spp. infection and specimen type with odds of infection being higher for ear canal and skin compared to urine specimens. There were higher proportions of samples resistant to clindamycin 34.2% (13/25), ampicillin 32.4% (2/26), lincospectin 31.6% (12/26) and penicillin-G 29.0% (11/27). Sixty three percent (24/38) of Staphylococcus spp. were resistant to one antimicrobial agent and 15.8% were multidrug resistant (MDR). MDR was more common among S. aureus 28.6% (2/7) than S. intermedius group isolates 11.8% (2/17). One S. intermedius group isolate was resistant to all β-lactam antimicrobial agents tested. S. intermedius group was the most common cause of skin infections and antimicrobial resistance was not wide spread among cats presented at the veterinary academic hospital in South Africa. However, the presence of MDR-Staphylococcus spp. and isolates resistant to all β-lactams is of both public health and animal health concern.

Occurrence of antimicrobial resistant bacteria in healthy dogs and cats presented to private veterinary hospitals in southern Ontario: A preliminary study

PubMed Central

Murphy, Colleen; Reid-Smith, Richard J.; Prescott, John F.; Bonnett, Brenda N.; Poppe, Cornelis; Boerlin, Patrick; Weese, J. Scott; Janecko, Nicol; McEwen, Scott A.

2009-01-01

The prevalence and patterns of antimicrobial susceptibility of fecal Escherichia coli, Salmonella spp., extended β-lactamase producing E. coli (ESBL-E. coli), methicillin-resistant Staphylococcus aureus (MRSA), and methicillin-resistant Staphylococcus pseudintermedius (MRSP) were determined for healthy dogs (n = 188) and cats (n = 39) from veterinary hospitals in southern Ontario that had not had recent exposure to antimicrobials. The prevalence of antimicrobial resistance in E. coli was as follows: streptomycin (dogs — 17%, cats — 2%), ampicillin (dogs — 13%, cats — 4%), cephalothin (dogs — 13%, cats — < 1%), and tetracycline (dogs — 11%, cats — 2%). Eleven percent of dogs and 15% of cats had isolates that were resistant to at least 2 antimicrobials. Cephamycinase (CMY)-2 producing E. coli was cultured from 2 dogs. No Salmonella spp., ESBL-E. coli, MRSA, or MRSP isolates were recovered. The observed prevalence of resistance in commensal E. coli from this population was lower than that previously reported in companion animals, but a small percentage of dogs may be a reservoir for CMY-2 E. coli. PMID:20046603

Escherichia coli and Staphylococcus aureus: bad news and good news from the European Antimicrobial Resistance Surveillance Network (EARS-Net, formerly EARSS), 2002 to 2009.

PubMed

Gagliotti, C; Balode, A; Baquero, F; Degener, J; Grundmann, H; Gür, D; Jarlier, V; Kahlmeter, G; Monen, J; Monnet, D L; Rossolini, G M; Suetens, C; Weist, K; Heuer, O

2011-03-17

Based on data collected by the European Antimicrobial Resistance Surveillance Network (EARS-Net) and the former EARSS, the present study describes the trends in antimicrobial susceptibility patterns and occurrence of invasive infections caused by Escherichia coli and Staphylococcus aureus in the period from 2002 to 2009. Antimicrobial susceptibility results from 198 laboratories in 22 European countries reporting continuously on these two microorganisms during the entire study period were included in the analysis. The number of bloodstream infections caused by E. coli increased remarkably by 71% during the study period, while bloodstream infections caused by S. aureus increased by 34%. At the same time, an alarming increase of antimicrobial resistance in E. coli was observed, whereas for S. aureus the proportion of meticillin resistant isolates decreased. The observed trend suggests an increasing burden of disease caused by E. coli. The reduction in the proportion of meticillin-resistant S. aureus and the lesser increase in S. aureus infections, compared with E. coli, may reflect the success of infection control measures at hospital level in several European countries.

Antimicrobial resistance among Escherichia coli that cause childhood community-acquired urinary tract infections in Northern Italy.

PubMed

Caracciolo, Alessandra; Bettinelli, Alberto; Bonato, Claudio; Isimbaldi, Clementina; Tagliabue, Alessandro; Longoni, Laura; Bianchetti, Mario G

2011-01-06

Resistance rate of Escherichia coli against antimicrobials that are commonly prescribed in pediatric urinary tract infections is currently a matter of concern. The antimicrobial susceptibility patterns of uropathogenic Escherichia coli strains to the common antibimcrobials ampicillin, cotrimoxazole, coamoxyclav, ceftazidime, ceftriaxone, nitrofurantoin, and gentamycin were determined in 177 children aged from 2 to 36 months. They presented with their first symptomatic community acquired urinary tract infection at the Department of Pediatrics, San Leopoldo Mandic Hospital, Merate-Lecco. High rates of ampicillin (inpatients: 50%; outpatients: 52%) resistance were identified. The resistance for cotrimoxazole (inpatients: 22%; outpatients: 15%) and especially coamoxyclav (inpatients: 6%; outpatients: 10%) was less pronounced than that to ampicillin. No resistance or less than 1% of resistance was identified for ceftazidime, ceftriaxone, nitrofurantoin, and gentamycin both in inpatients and in outpatients. Italian children affected with a community acquired urinary tract infection are initially managed orally with coamoxyclav or parenterally with ceftriaxone. The results of the present retrospective analysis support this attitude. Parenteral ceftriaxone or an aminoglycoside should be considered for patients on antimicrobial prophylaxis or recently prescribed antimicrobials.

Antimicrobial susceptibility of Brachyspira hyodysenteriae in Switzerland.

PubMed

Kirchgässner, C; Schmitt, S; Borgström, A; Wittenbrink, M M

2016-06-01

Brachyspira (B.) hyodysenteriae is the causative agent of swine dysentery (SD), a severe mucohaemorrhagic diarrheal disease in pigs worldwide. So far, the antimicrobial susceptibility patterns of B. hyodysenteriae in Switzerland have not been investigated. Therefore, a panel of 30 porcine B. hyodysenteriae isolates were tested against 6 antimicrobial agents by using the VetMIC Brachy panel, a broth microdilution test. Tiamulin and valnemulin showed high antimicrobial activity inhibiting all isolates at low concentrations. The susceptibility testing of doxycycline revealed values from ≤0.25 μg/ ml (47%) to 2 μg/ml (10%). The MIC values of lincomycin ranged between ≤0.5 μg/ml (30%) and 32 μg/ml (43%). For tylosin, 57% of the isolates could not be inhibited at the highest concentration of ≥128 μg/ml. The MIC values for tylvalosin were between ≤0.25 μg/ml (10%) and 8 μg/ml (20%). These findings reveal Switzerland's favourable situation compared to other European countries. Above all, tiamulin and valnemulin are still effective antimicrobial agents and can be further used for the treatment of SD.

Clinical and Microbiological Aspects of β-Lactam Resistance in Staphylococcus lugdunensis

PubMed Central

McHardy, Ian H.; Veltman, Jennifer; Hindler, Janet; Bruxvoort, Katia; Carvalho, Marissa M.

2016-01-01

ABSTRACT Antimicrobial susceptibility results from broth microdilution MIC testing of 993 Staphylococcus lugdunensis isolates recovered from patients at a tertiary care medical center from 2008 to 2015 were reviewed. Ninety-two oxacillin-susceptible isolates were selected to assess the accuracy of penicillin MIC testing, the penicillin disk diffusion test, and three β-lactamase tests, including the cefoxitin-induced nitrocefin test, penicillin cloverleaf assay, and penicillin disk zone edge test. The results of all phenotypic tests were compared to the results of blaZ PCR. The medical records of 62 patients from whom S. lugdunensis was isolated, including 31 penicillin-susceptible and 31 penicillin-resistant strains, were retrospectively reviewed to evaluate the clinical significance of S. lugdunensis isolation, the antimicrobial agents prescribed, if any, and the clinical outcome. MIC testing revealed that 517/993 (52.1%) isolates were susceptible to penicillin and 946/993 (95.3%) were susceptible to oxacillin. The induced nitrocefin test was 100% sensitive and specific for the detection of β-lactamase compared to the blaZ PCR results, whereas the penicillin disk zone edge and cloverleaf tests showed sensitivities of 100% but specificities of only 9.1% and 89.1%, respectively. The penicillin MIC test had 100% categorical agreement with blaZ PCR, while penicillin disk diffusion yielded one major error. Only 3/31 patients with penicillin-susceptible isolates were treated with a penicillin family antimicrobial. The majority of cases were treated with other β-lactams, trimethoprim-sulfamethoxazole, or vancomycin. These data indicate that nearly all isolates of S. lugdunensis are susceptible to narrow-spectrum antimicrobial agents. Clinical laboratories in areas with resistance levels similar to those described here can help promote the use of these agents versus vancomycin by effectively designing their antimicrobial susceptibility reports to convey this message. PMID:27927926

Clinical and Microbiological Aspects of β-Lactam Resistance in Staphylococcus lugdunensis.

PubMed

McHardy, Ian H; Veltman, Jennifer; Hindler, Janet; Bruxvoort, Katia; Carvalho, Marissa M; Humphries, Romney M

2017-02-01

Antimicrobial susceptibility results from broth microdilution MIC testing of 993 Staphylococcus lugdunensis isolates recovered from patients at a tertiary care medical center from 2008 to 2015 were reviewed. Ninety-two oxacillin-susceptible isolates were selected to assess the accuracy of penicillin MIC testing, the penicillin disk diffusion test, and three β-lactamase tests, including the cefoxitin-induced nitrocefin test, penicillin cloverleaf assay, and penicillin disk zone edge test. The results of all phenotypic tests were compared to the results of blaZ PCR. The medical records of 62 patients from whom S. lugdunensis was isolated, including 31 penicillin-susceptible and 31 penicillin-resistant strains, were retrospectively reviewed to evaluate the clinical significance of S. lugdunensis isolation, the antimicrobial agents prescribed, if any, and the clinical outcome. MIC testing revealed that 517/993 (52.1%) isolates were susceptible to penicillin and 946/993 (95.3%) were susceptible to oxacillin. The induced nitrocefin test was 100% sensitive and specific for the detection of β-lactamase compared to the blaZ PCR results, whereas the penicillin disk zone edge and cloverleaf tests showed sensitivities of 100% but specificities of only 9.1% and 89.1%, respectively. The penicillin MIC test had 100% categorical agreement with blaZ PCR, while penicillin disk diffusion yielded one major error. Only 3/31 patients with penicillin-susceptible isolates were treated with a penicillin family antimicrobial. The majority of cases were treated with other β-lactams, trimethoprim-sulfamethoxazole, or vancomycin. These data indicate that nearly all isolates of S. lugdunensis are susceptible to narrow-spectrum antimicrobial agents. Clinical laboratories in areas with resistance levels similar to those described here can help promote the use of these agents versus vancomycin by effectively designing their antimicrobial susceptibility reports to convey this message. Copyright © 2017 American Society for Microbiology.

Supervised learning for infection risk inference using pathology data.

PubMed

Hernandez, Bernard; Herrero, Pau; Rawson, Timothy Miles; Moore, Luke S P; Evans, Benjamin; Toumazou, Christofer; Holmes, Alison H; Georgiou, Pantelis

2017-12-08

Antimicrobial Resistance is threatening our ability to treat common infectious diseases and overuse of antimicrobials to treat human infections in hospitals is accelerating this process. Clinical Decision Support Systems (CDSSs) have been proven to enhance quality of care by promoting change in prescription practices through antimicrobial selection advice. However, bypassing an initial assessment to determine the existence of an underlying disease that justifies the need of antimicrobial therapy might lead to indiscriminate and often unnecessary prescriptions. From pathology laboratory tests, six biochemical markers were selected and combined with microbiology outcomes from susceptibility tests to create a unique dataset with over one and a half million daily profiles to perform infection risk inference. Outliers were discarded using the inter-quartile range rule and several sampling techniques were studied to tackle the class imbalance problem. The first phase selects the most effective and robust model during training using ten-fold stratified cross-validation. The second phase evaluates the final model after isotonic calibration in scenarios with missing inputs and imbalanced class distributions. More than 50% of infected profiles have daily requested laboratory tests for the six biochemical markers with very promising infection inference results: area under the receiver operating characteristic curve (0.80-0.83), sensitivity (0.64-0.75) and specificity (0.92-0.97). Standardization consistently outperforms normalization and sensitivity is enhanced by using the SMOTE sampling technique. Furthermore, models operated without noticeable loss in performance if at least four biomarkers were available. The selected biomarkers comprise enough information to perform infection risk inference with a high degree of confidence even in the presence of incomplete and imbalanced data. Since they are commonly available in hospitals, Clinical Decision Support Systems could benefit from these findings to assist clinicians in deciding whether or not to initiate antimicrobial therapy to improve prescription practices.

Widespread acquisition of antimicrobial resistance among Campylobacter isolates from UK retail poultry and evidence for clonal expansion of resistant lineages.

PubMed

Wimalarathna, Helen M L; Richardson, Judith F; Lawson, Andy J; Elson, Richard; Meldrum, Richard; Little, Christine L; Maiden, Martin C J; McCarthy, Noel D; Sheppard, Samuel K

2013-07-15

Antimicrobial resistance is increasing among clinical Campylobacter cases and is common among isolates from other sources, specifically retail poultry - a major source of human infection. In this study the antimicrobial susceptibility of isolates from a UK-wide survey of Campylobacter in retail poultry in 2001 and 2004-5 was investigated. The occurrence of phenotypes resistant to tetracycline, quinolones (ciprofloxacin and naladixic acid), erythromycin, chloramphenicol and aminoglycosides was quantified. This was compared with a phylogeny for these isolates based upon Multi Locus Sequence Typing (MLST) to investigate the pattern of antimicrobial resistance acquisition. Antimicrobial resistance was present in all lineage clusters, but statistical testing showed a non-random distribution. Erythromycin resistance was associated with Campylobacter coli. For all antimicrobials tested, resistant isolates were distributed among relatively distant lineages indicative of widespread acquisition. There was also evidence of clustering of resistance phenotypes within lineages; indicative of local expansion of resistant strains. These results are consistent with the widespread acquisition of antimicrobial resistance among chicken associated Campylobacter isolates, either through mutation or horizontal gene transfer, and the expansion of these lineages as a proportion of the population. As Campylobacter are not known to multiply outside of the host and long-term carriage in humans is extremely infrequent in industrialized countries, the most likely location for the proliferation of resistant lineages is in farmed chickens.

Prevalence and antimicrobial resistance pattern of Salmonella in animal feed produced in Namibia.

PubMed

Shilangale, Renatus P; Di Giannatale, Elisabetta; Chimwamurombe, Percy M; Kaaya, Godwin P

2012-01-01

The occurrence of Salmonella is a global challenge in the public health and food production sectors. Our study investigated the prevalence, serovar and antimicrobial susceptibility of strains of Salmonella serovars isolated from animal feed (meat-and-bone and blood meal) samples from two commercial abattoirs in Namibia. A total of 650 samples (n=650) were examined for the presence of Salmonella. Results showed that 10.9% (n=71) were positive for Salmonella. Of the Salmonella serovars isolated, S. Chester was the most commonly isolated serovar (19.7%), followed by S. Schwarzengrund at 12.7%. From the Salmonella isolates, 19.7% (n=14) were resistant to one or more of the antimicrobials (nalidixic acid, trimethoprim-sulfamethoxazole, sulfisoxazole, streptomycin and/or tetracycline), whereas 80.3% (n=57) were susceptible to all 16 antimicrobials tested. Resistance to sulfisoxazole and the trimethroprimsuflamethoxazole combination were the most common. The resistant isolates belonged to ten different Salmonella serovars. The susceptibility of most of the Salmonella isolated to the antimicrobials tested indicates that anti-microbial resistance is not as common and extensive in Namibia as has been reported in many other countries. It also appears that there is a range of antimicrobials available that are effective in managing Salmonella infections in Namibia. However, there is some evidence that resistance is developing and this will need further monitoring to ensure it does not become a problem.

Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

PubMed

Castillo-Rojas, Gonzalo; Mazari-Hiríart, Marisa; Ponce de León, Sergio; Amieva-Fernández, Rosa I; Agis-Juárez, Raúl A; Huebner, Johannes; López-Vidal, Yolanda

2013-01-01

Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area) and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation), respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE). E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species.

Comparison of Enterococcus faecium and Enterococcus faecalis Strains Isolated from Water and Clinical Samples: Antimicrobial Susceptibility and Genetic Relationships

PubMed Central

Castillo-Rojas, Gonzalo; Mazari-Hiríart, Marisa; Ponce de León, Sergio; Amieva-Fernández, Rosa I.; Agis-Juárez, Raúl A.; Huebner, Johannes; López-Vidal, Yolanda

2013-01-01

Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area) and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation), respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE). E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species. PMID:23560050

Colonization prevalence and antibiotic susceptibility of Group B Streptococcus in pregnant women over a 6-year period in Dongguan, China

PubMed Central

Guo, Zhusheng; Xie, Shujin; Yang, Weiqing; Chen, Junjian; Wang, Jiamin; Cheng, Zhiqin; Wang, Xin; Zhu, Xuehai; Wang, Jianwen; Wang, Haiqing; Huang, Juan; Liang, Ning; McIver, David J.

2017-01-01

This study investigated the prevalence of recto-vaginal Group B Streptococcus (GBS) colonization, serotype distribution, and antimicrobial susceptibility patterns among pregnant women in Dongguan, China. Recto-vaginal swabs were collected from pregnant women at gestational age 35–37 weeks between January 1st 2009 and December 31st 2014. Isolates were serotyped by latex-agglutination and were tested against seven antimicrobials by disk diffusion. Of 7,726 pregnant women who completed GBS testing, 636 (8.2%) were GBS carriers. Of 153 GBS isolates available for typing, 6 serotypes (Ia, Ib, III, V, VI and VIII) were identified with type III being predominant, while 9 (5.9%) were non-typable isolates. All isolates were sensitive to penicillin, ceftriaxone, linezolid and vancomycin, whereas 52.4% were resistant to clindamycin, 25.9% were resistant to levofloxacin and 64.9% were resistant to erythromycin. This study showed the recto-vaginal colonization prevalence of GBS in Dongguan is significant. Due to 100% susceptibility to penicillin of all GBS samples, penicillin remains the first recommendation for treatment and prevention against GBS infection. Susceptibility testing should be performed for women allergic to penicillin in order to choose the most appropriate antibacterial agents for treatment and prevention of vertical transmission to neonates. In addition, we suggest establishing standard processes for GBS culture and identification in China as early as possible. PMID:28813477

Clinico-microbiological study of Pseudomonas aeruginosa in wound infections and the detection of metallo-β-lactamase production.

PubMed

Bangera, Divya; Shenoy, Suchitra M; Saldanha, Dominic Rm

2016-12-01

Pseudomonas aeruginosa is a common opportunistic pathogen of humans among the Gram-negative bacilli. Clinically, it is associated with nosocomial infections like burns and surgical-site wound infections and remains a major health concern, especially among critically ill and immunocompromised patients. This is a prospective laboratory-based 2 year study conducted to isolate P. aeruginosa from wound specimens and the antimicrobial susceptibility pattern with reference to metallo-β-lactamase (MBL) production. Two hundred and twenty-four samples of P. aeruginosa isolated from wound specimens were included in the study. Antimicrobial susceptibility was done as per Clinical Laboratory Standard Institute (CLSI) guidelines. MBL-producing P. aeruginosa was detected using the EDTA disk diffusion synergy test. Statistical analysis was done using the SPSS 11 package (SPSS Inc., Chicago, IL). Out of the 224 P. aeruginosa isolates, 100% were susceptible to polymyxin B and colistin, 92·8% were sensitive to imipenem, 38% showed resistance to gentamicin followed by ceftazidime (31·69%) and meropenem (33·03). Sixteen (7·14%) isolates showed MBL production. Infection caused by drug-resistant P. aeruginosa is important to identify as it poses a therapeutic problem and is also a serious concern for infection control management. The acquired resistance genes can be horizontally transferred to other pathogens or commensals if aseptic procedures are not followed. © 2015 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Deletion of HAPS_2096 Increases Sensitivity to Cecropin B in Haemophilus parasuis.

PubMed

Chen, Fanjie; Hu, Han; Li, Zhonghua; Huang, Jiacheng; Cai, Xuwang; Wang, Chunmei; He, Qigai; Cao, Jiyue

2015-01-01

Cecropin B (CB) is a very effective natural antimicrobial peptide that has shown great potential for future antimicrobial drug development. HAPS_2096 is a Haemophilus parasuis gene that encodes the periplasmic substrate-binding protein of an ATP-binding cassette-type amino acid transporter. In this research, we constructed and verified an HAPS_2096 deletion mutant and a complementary HAPS_2096 mutant of H. parasuis JS0135. A bactericidal assay revealed that the HAPS_2096 deletion mutant was significantly more sensitive than the wild-type strain to 0.25-0.5 µg/ml CB. However, the gene complementation alleviated the CB sensitivity of the mutant. Immunoelectron microscopy observation following a 30-min treatment with a sublethal concentration of CB (0.25 μg/ml) revealed more extensive morphological damage in the mutant strain than in the wild-type strain. Hence, our results suggest that the HAPS_2096 gene contributes to H. parasuis resistance to CB. © 2015 S. Karger AG, Basel.

Identification of Proteus mirabilis Mutants with Increased Sensitivity to Antimicrobial Peptides

PubMed Central

McCoy, Andrea J.; Liu, Hongjian; Falla, Timothy J.; Gunn, John S.

2001-01-01

Antimicrobial peptides (APs) are important components of the innate defenses of animals, plants, and microorganisms. However, some bacterial pathogens are resistant to the action of APs. For example, Proteus mirabilis is highly resistant to the action of APs, such as polymyxin B (PM), protegrin, and the synthetic protegrin analog IB-367. To better understand this resistance, a transposon mutagenesis approach was used to generate P. mirabilis mutants sensitive to APs. Four unique PM-sensitive mutants of P. mirabilis were identified (these mutants were >2 to >128 times more sensitive than the wild type). Two of these mutants were also sensitive to IB-367 (16 and 128 times more sensitive than the wild type). Lipopolysaccharide (LPS) profiles of the PM- and protegrin-sensitive mutants demonstrated marked differences in both the lipid A and O-antigen regions, while the PM-sensitive mutants appeared to have alterations of either lipid A or O antigen. Matrix-assisted laser desorption ionization–time of flight mass spectrometry analysis of the wild-type and PM-sensitive mutant lipid A showed species with one or two aminoarabinose groups, while lipid A from the PM- and protegrin-sensitive mutants was devoid of aminoarabinose. When the mutants were streaked on an agar-containing medium, the swarming motility of the PM- and protegrin-sensitive mutants was completely inhibited and the swarming motility of the mutants sensitive to only PM was markedly decreased. DNA sequence analysis of the mutagenized loci revealed similarities to an O-acetyltransferase (PM and protegrin sensitive) and ATP synthase and sap loci (PM sensitive). These data further support the role of LPS modifications as an elaborate mechanism in the resistance of certain bacterial species to APs and suggest that LPS surface charge alterations may play a role in P. mirabilis swarming motility. PMID:11408219

[Antibiotic resistance pattern of 24, 526 strains of Vibrio cholerae O1 isolated in Mexico from 1991 to 1993].

PubMed

Giono-Cerezo, S; Zárate, A; Gutiérrez, L; Valdespino, J L

1994-01-01

Profile of antimicrobial resistance by Kirby-Bauer method was performed on 24526 Vibrio cholerae O1 strains isolated in México (1991-1993) from fecal swabs in cholera cases and from asymptomatic carriers. Minimal inhibitory concentration (MIC) tests for tetracycline (Te) and doxycycline (D) were done on selected strains. Single antibiotic discs were used at concentrations of: Te, 30 micrograms; D, 30 micrograms; erythromycin (E), 15 micrograms; chloramphenicol (CM), 30 micrograms; ampicillin (AM), 10 micrograms; trimethoprim-sulfamethoxazole (SXT) 1.25 micrograms/23.75 micrograms. Strains whose halos were of a smaller diameter than the intermediate value were considered resistant. It is important to maintain surveillance on antimicrobial susceptibility as epidemiological marker on geographical selected areas in order to detect changes of resistant patterns.

Antimicrobial Properties of Biofunctionalized Silver Nanoparticles on Clinical Isolates of Streptococcus mutans and Its Serotypes

PubMed Central

Martínez-Robles, Ángel Manuel; Loyola-Rodríguez, Juan Pablo; Zavala-Alonso, Norma Verónica; Martinez-Martinez, Rita Elizabeth; Ruiz, Facundo; Lara-Castro, René Homero; Donohué-Cornejo, Alejandro; Reyes-López, Simón Yobanny; Espinosa-Cristóbal, León Francisco

2016-01-01

(1) Background: Streptococcus mutans (S. mutans) is the principal pathogen involved in the formation of dental caries. Other systemic diseases have also been associated with specific S. mutans serotypes (c, e, f, and k). Silver nanoparticles (SNP) have been demonstrated to have good antibacterial effects against S. mutans; therefore, limited studies have evaluated the antimicrobial activity of biofunctionalized SNP on S. mutans serotypes. The purpose of this work was to prepare and characterize coated SNP using two different organic components and to evaluate the antimicrobial activity of SNP in clinical isolates of S. mutans strains and serotypes; (2) Methods: SNP with bovine serum albumin (BSA) or chitosan (CS) coatings were prepared and the physical, chemical and microbiological properties of SNP were evaluated; (3) Results: Both types of coated SNP showed antimicrobial activity against S. mutans bacteria and serotypes. Better inhibition was associated with smaller particles and BSA coatings; however, no significant differences were found between the different serotypes, indicating a similar sensitivity to the coated SNP; (4) Conclusion: This study concludes that BSA and CS coated SNP had good antimicrobial activity against S. mutans strains and the four serotypes, and this study suggest the widespread use of SNP as an antimicrobial agent for the inhibition of S. mutans bacteria. PMID:28335264

Antimicrobial Properties of Biofunctionalized Silver Nanoparticles on Clinical Isolates of Streptococcus mutans and Its Serotypes.

PubMed

Martínez-Robles, Ángel Manuel; Loyola-Rodríguez, Juan Pablo; Zavala-Alonso, Norma Verónica; Martinez-Martinez, Rita Elizabeth; Ruiz, Facundo; Lara-Castro, René Homero; Donohué-Cornejo, Alejandro; Reyes-López, Simón Yobanny; Espinosa-Cristóbal, León Francisco

2016-07-22

(1) Background: Streptococcus mutans ( S. mutans ) is the principal pathogen involved in the formation of dental caries. Other systemic diseases have also been associated with specific S. mutans serotypes ( c , e , f , and k ). Silver nanoparticles (SNP) have been demonstrated to have good antibacterial effects against S. mutans ; therefore, limited studies have evaluated the antimicrobial activity of biofunctionalized SNP on S. mutans serotypes. The purpose of this work was to prepare and characterize coated SNP using two different organic components and to evaluate the antimicrobial activity of SNP in clinical isolates of S. mutans strains and serotypes; (2) Methods: SNP with bovine serum albumin (BSA) or chitosan (CS) coatings were prepared and the physical, chemical and microbiological properties of SNP were evaluated; (3) Results: Both types of coated SNP showed antimicrobial activity against S. mutans bacteria and serotypes. Better inhibition was associated with smaller particles and BSA coatings; however, no significant differences were found between the different serotypes, indicating a similar sensitivity to the coated SNP; (4) Conclusion: This study concludes that BSA and CS coated SNP had good antimicrobial activity against S. mutans strains and the four serotypes, and this study suggest the widespread use of SNP as an antimicrobial agent for the inhibition of S. mutans bacteria.

Antimicrobial resistance of Listeria monocytogenes and Listeria innocua from meat products and meat-processing environment.

PubMed

Gómez, Diego; Azón, Ester; Marco, Noelia; Carramiñana, Juan J; Rota, Carmina; Ariño, Agustín; Yangüela, Javier

2014-09-01

A total of 336 Listeria isolates from ready-to-eat (RTE) meat products and meat-processing environments, consisting of 206 Listeria monocytogenes, and 130 Listeria innocua isolates, were characterized by disc diffusion assay and minimum inhibitory concentration (MIC) values for antimicrobial susceptibility against twenty antimicrobials. Resistance to one or two antimicrobials was observed in 71 L. monocytogenes isolates (34.5%), and 56 L. innocua isolates (43.1%). Multidrug resistance was identified in 24 Listeria isolates, 18 belonging to L. innocua (13.9%) and 6 to L. monocytogenes (2.9%). Oxacillin resistance was the most common resistance phenotype and was identified in 100% Listeria isolates. A medium prevalence of resistance to clindamycin (39.3% isolates) and low incidence of resistance to tetracycline (3.9% isolates) were also detected. Listeria isolates from RTE meat products displayed higher overall antimicrobial resistance (31.3%) than those from the environment (13.4%). All the strains assayed were sensitive to the preferred antibiotics used to treat listeriosis. Results showed that although antimicrobial resistance in L. monocytogenes still occurs at a low prevalence, L. innocua can form a reservoir of resistance genes which may transfer between bacterial species, including transference to organisms capable of causing disease in humans. Copyright © 2014 Elsevier Ltd. All rights reserved.

In vitro antimicrobial activity of five essential oils on multidrug resistant Gram-negative clinical isolates.

PubMed

Sakkas, Hercules; Gousia, Panagiota; Economou, Vangelis; Sakkas, Vassilios; Petsios, Stefanos; Papadopoulou, Chrissanthy

2016-01-01

The emergence of drug-resistant pathogens has drawn attention on medicinal plants for potential antimicrobial properties. The objective of the present study was the investigation of the antimicrobial activity of five plant essential oils on multidrug resistant Gram-negative bacteria. Basil, chamomile blue, origanum, thyme, and tea tree oil were tested against clinical isolates of Acinetobacter baumannii (n = 6), Escherichia coli (n = 4), Klebsiella pneumoniae (n = 7), and Pseudomonas aeruginosa (n = 5) using the broth macrodilution method. The tested essential oils produced variable antibacterial effect, while Chamomile blue oil demonstrated no antibacterial activity. Origanum, Thyme, and Basil oils were ineffective on P. aeruginosa isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values ranged from 0.12% to 1.50% (v/v) for tea tree oil, 0.25-4% (v/v) for origanum and thyme oil, 0.50% to >4% for basil oil and >4% for chamomile blue oil. Compared to literature data on reference strains, the reported MIC values were different by 2SD, denoting less successful antimicrobial activity against multidrug resistant isolates. The antimicrobial activities of the essential oils are influenced by the strain origin (wild, reference, drug sensitive, or resistant) and it should be taken into consideration whenever investigating the plants' potential for developing new antimicrobials.

Potential of the polymer poly-[2-(tert-butylamino) methylstyrene] as antimicrobial packaging material for meat products.

PubMed

Dohlen, S; Braun, C; Brodkorb, F; Fischer, B; Ilg, Y; Kalbfleisch, K; Lorenz, R; Robers, O; Kreyenschmidt, M; Kreyenschmidt, J

2016-10-01

The objective of the study was to investigate the antimicrobial potential of a new SAM(®) polymer poly(TBAMS) as packaging material for meat products. The influence of temperature, time and product factors on the antimicrobial activity of poly(TBAMS) against different bacteria was determined using a modified test method based on the Japanese Industrial Standard 2801:2000. Results showed a significant reduction in bacterial counts on poly(TBAMS) compared with the reference material of several meat-specific micro-organisms after 24 h at 7°C. Bacterial counts of Staphylococcus aureus, Listeria monocytogenes, Lactobacillus spp., Brochothrix thermosphacta and Escherichia coli were reduced by >4·0 log10  units. Pseudomonas fluorescens was less sensitive to poly(TBAMS) within 24 h between 2 and 7°C. Prolonging the storage time to 48 h, however, resulted in an increased reduction rate. Furthermore, antimicrobial activity was also observed if meat components in the form of meat extract, meat juice or bovine serum albumin protein were present. Antimicrobial activity was also achieved if inoculated with mixed cultures. Poly(TBAMS) showed antimicrobial properties under conditions typical for meat supply chains. Poly(TBAMS) bears a high potential to increase safety and shelf life of meat products. © 2016 The Society for Applied Microbiology.

Antimicrobial Treatment Options for Granulomatous Mastitis Caused by Corynebacterium Species

PubMed Central

Dobinson, Hazel C.; Anderson, Trevor P.; Chambers, Stephen T.; Doogue, Matthew P.; Seaward, Lois

2015-01-01

Corynebacterium species are increasingly recognized as important pathogens in granulomatous mastitis. Currently, there are no published treatment protocols for Corynebacterium breast infections. This study describes antimicrobial treatment options in the context of other management strategies used for granulomatous mastitis. Corynebacterium spp. isolated from breast tissue and aspirate samples stored from 2002 to 2013 were identified and determined to the species level using matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS), 16S RNA sequencing, and rpoB gene targets. The MICs for 12 antimicrobials were performed using Etest for each isolate. Correlations of these with antimicrobial characteristics, choice of antimicrobial, and disease outcome were evaluated. Corynebacterium spp. from breast tissue and aspirate samples were confirmed in 17 isolates from 16 patients. Based on EUCAST breakpoints, Corynebacterium kroppenstedtii isolates (n = 11) were susceptible to seven antibiotic classes but resistant to β-lactam antibiotics. Corynebacterium tuberculostearicum isolates (n = 4) were multidrug resistant. Two nonlipophilic species were isolated, Corynebacterium glucuronolyticum and Corynebacterium freneyi, both of which have various susceptibilities to antimicrobial agents. Short-course antimicrobial therapy was common (median, 6 courses per subject; range, 1 to 9 courses). Patients with C. kroppenstedtii presented with a hot painful breast mass and underwent multiple surgical procedures (median, 4 procedures; range, 2 to 6 procedures). The management of Corynebacterium breast infections requires a multidisciplinary approach and includes culture and appropriate sensitivity testing to guide antimicrobial therapy. Established infections have a poor outcome, possibly because adequate concentrations of some drugs will be difficult to achieve in lipophilic granulomata. Lipophilic antimicrobial therapy may offer a therapeutic advantage. The role of immunotherapy has not been defined. PMID:26135858

Antimicrobial resistance, serotypes, and virulence factors of Streptococcus suis isolates from diseased pigs.

PubMed

Li, Lu-Lu; Liao, Xiao-Ping; Sun, Jian; Yang, Yu-Rong; Liu, Bao-Tao; Yang, Shou-Shen; Zhao, Dong-Hao; Liu, Ya-Hong

2012-07-01

Streptococcus suis isolates from diseased pigs were examined for susceptibility to nine antimicrobials, possession of virulence-associated factors (VFs), and distribution of serotypes. The association between antimicrobial resistance (AMR) and serotypes as well as VFs was subsequently assessed. Among the isolates investigated, serotype 2 (66.04%) was mostly prevalent, followed by serotypes 1 (23.27%), 9 (1.26%), and 7 (0.63%), whereas 14 isolates were untypable by the polymerase chain reaction typing method used. Analysis with pulsed-field gel electrophoresis revealed the isolates had diverse DNA macrorestriction patterns. The frequency of antimicrobial resistance among the S. suis isolates was higher than that reported from other countries. It is notable that multiple antimicrobial resistance (three or more antimicrobials) was observed with 98.73% of the S. suis isolates, and the dominant resistance phenotype was erythromycin-tilmicosin-clindamycin-chloramphenicol-levofloxacin-ceftiofur-kanamycin-tetracycline-penicillin (35.85%). The most prevalent VFs were those encoded by muramidase-released protein (61.64%), followed by suilysin (56.60%) and extracellular factor (46.54%). Presence of VFs and the possession of certain AMR phenotypes were significantly associated as determined by statistical analysis. Together, these findings indicate that the clinical S. suis isolates obtained from diseased pigs in China are genetically diverse, are resistant to multiple antibiotics of clinical importance, and carry known virulence factors.

Antimicrobial resistance profiles of Enterococcus faecalis and Enterococcus faecium isolated from artisanal food of animal origin in Argentina.

PubMed

Delpech, Gastón; Pourcel, Gisela; Schell, Celia; De Luca, María; Basualdo, Juan; Bernstein, Judith; Grenovero, Silvia; Sparo, Mónica

2012-10-01

Enterococci are part of the indigenous microbiota of human gastrointestinal tract and food of animal origin. Enterococci inhabiting non-human reservoirs play a critical role in the acquisition and dissemination of antimicrobial resistance determinants. The aim of this work was to investigate the antimicrobial resistance in Enterococcus faecalis and Enterococcus faecium strains recovered from artisanal food of animal origin. Samples of goat cheese (n = 42), cow cheese (n = 40), artisanal salami (n = 30), and minced meat for the manufacture of hamburgers (n = 60) were analyzed. Phenotypic and genotypic tests for species-level identification of the recovered isolates were carried out. Minimum inhibitory concentration (MIC) study for in vitro quantitative antimicrobial resistance assessment was performed, and 71 E. faecalis and 22 E. faecium were isolated. The recovered enterococci showed different multi-drug resistance patterns that included tretracycline, erythromycin, ciprofloxacin, linezolid, penicillin, ampicillin, vancomycin, teicoplanin, gentamicin (high-level resistance), and streptomycin (high-level resistance). VanA-type E. faecium were detected. β-lactamase activity was not observed. Artisanal foods of animal origin act as a non-human reservoir of E. faecalis and E. faecuim strains, expressing multi-resistance to antimicrobials. In conclusion, the implementation of a continuous antimicrobial resistance surveillance in enterococci isolated from artisanal food of animal origin is important.

Genetic diversity and antimicrobial resistance pattern of Salmonella enterica serovar Enteritidis clinical isolates in Thailand.

PubMed

Utrarachkij, Fuangfa; Nakajima, Chie; Siripanichgon, Kanokrat; Changkaew, Kanjana; Thongpanich, Yuwanda; Pornraungwong, Srirat; Suthienkul, Orasa; Suzuki, Yasuhiko

2016-04-01

To trace the history of antimicrobial resistance in Salmonella enterica serovar Enteritidis (S. Enteritidis, SE) circulating in Thailand, we characterised clinical isolates obtained during 2004-2007. Antimicrobial resistance profiles, multi-locus variable number tandem repeat analysis (MLVA) types and 3 representative virulence determinants (spvA, sodCI and sopE) were established from SE isolates (n = 192) collected from stool and blood of patients throughout Thailand during the period 2004-2007. Resistance was found in SE against 10 out of 11 antimicrobials studied. The highest resistance ratios were observed for nalidixic acid (83.2%), ciprofloxacin (51.1%) and ampicillin (50.5%), and 25.5% were multidrug resistant. Based on five polymorphic tandem repeat loci analysis, MLVA identified 20 distinct types with three closely related predominant types. A significant increase of AMP resistance from 2004 to 2006 was strongly correlated with that of a MLVA type, 5-5-11-7-3. The usage of antimicrobials in human medicine or farm settings might act as selective pressures and cause the spread of resistant strains. Hence, a strict policy on antimicrobial usage needs to be implemented to achieve the control of resistant SE in Thailand. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Synthesis of curcumin-loaded chitosan phosphate nanoparticle and study of its cytotoxicity and antimicrobial activity.

PubMed

Deka, C; Aidew, L; Devi, N; Buragohain, A K; Kakati, D K

2016-11-01

Curcumin has acquired an important position in the treatment of various diseases. But its use, as a chemotherapeutic agent, is limited due to its low water solubility, poor bioavailability, and its sensitive nature at the physiological pH. To overcome this, curcumin was loaded into chitosan phosphate nanoparticles (CPNs). The loading efficiency was found to be 84%. DLS studies revealed the average particle size of CPNs and curcumin-loaded CPNs as 53 and 91 nm, respectively, and TEM results supplemented these values. A sustained release pattern was noticed and the amount of curcumin released in acidic pH was higher than at physiological pH. The curcumin nanoformulation exhibited proficient activity against both Gram-positive and Gram-negative bacteria as well as fungus. Cytocompatibility of the nanoformulations against peripheral blood mononuclear cells (PBMCs) and murine monocyte-macrophage cell line was confirmed by incubating with PBMCs and murine monocyte-macrophage cell line.

Molecular diagnostics for the detection and characterization of microbial pathogens.

PubMed

Procop, Gary W

2007-09-01

New and advanced methods of molecular diagnostics are changing the way we practice clinical microbiology, which affects the practice of medicine. Signal amplification and real-time nucleic acid amplification technologies offer a sensitive and specific result with a more rapid turnaround time than has ever before been possible. Numerous methods of postamplification analysis afford the simultaneous detection and differentiation of numerous microbial pathogens, their mechanisms of resistance, and the construction of disease-specific assays. The technical feasibility of these assays has already been demonstrated. How these new, often more expensive tests will be incorporated into routine practice and the impact they will have on patient care remain to be determined. One of the most attractive uses for such techniques is to achieve a more rapid characterization of the infectious agent so that a narrower-spectrum antimicrobial agent may be used, which should have an impact on resistance patterns.

Antimicrobial Prescribing in Dogs and Cats in Australia: Results of the Australasian Infectious Disease Advisory Panel Survey.

PubMed

Hardefeldt, L Y; Holloway, S; Trott, D J; Shipstone, M; Barrs, V R; Malik, R; Burrows, M; Armstrong, S; Browning, G F; Stevenson, M

2017-07-01

Investigations of antimicrobial use in companion animals are limited. With the growing recognition of the need for improved antimicrobial stewardship, there is urgent need for more detailed understanding of the patterns of antimicrobial use in this sector. To investigate antimicrobial use for medical and surgical conditions in dogs and cats by Australian veterinarians. A cross-sectional study was performed over 4 months in 2011. Respondents were asked about their choices of antimicrobials for empirical therapy of diseases in dogs and cats, duration of therapy, and selection based on culture and susceptibility testing, for common conditions framed as case scenarios: 11 medical, 2 surgical, and 8 dermatological. A total of 892 of the 1,029 members of the Australian veterinary profession that completed the survey satisfied the selection criteria. Empirical antimicrobial therapy was more common for acute conditions (76%) than chronic conditions (24%). Overall, the most common antimicrobial classes were potentiated aminopenicillins (36%), fluoroquinolones (15%), first- and second-generation cephalosporins (14%), and tetracyclines (11%). Third-generation cephalosporins were more frequently used in cats (16%) compared to dogs (2%). Agreement with Australasian Infectious Disease Advisory Panel (AIDAP) guidelines (generated subsequently) was variable ranging from 0 to 69% between conditions. Choice of antimicrobials by Australian veterinary practitioners was generally appropriate, with relatively low use of drugs of high importance, except for the empirical use of fluoroquinolones in dogs, particularly for otitis externa and 3rd-generation cephalosporins in cats. Future surveys will determine whether introduction of the 2013 AIDAP therapeutic guidelines has influenced prescribing habits. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

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.

Raman spectroscopy, electronic microscopy and SPME-GC-MS to elucidate the mode of action of a new antimicrobial food packaging material.

PubMed

Clemente, Isabel; Aznar, Margarita; Salafranca, Jesús; Nerín, Cristina

2017-02-01

One critical challenge when developing a new antimicrobial packaging material is to demonstrate the mode of action of the antimicrobials incorporated into the packaging. For this task, several analytical techniques as well as microbiology are required. In this work, the antimicrobial properties of benzyl isothiocyanate, allyl isothiocyanate and essential oils of cinnamon and oregano against several moulds and bacteria have been evaluated. Benzyl isothiocyanate showed the highest antimicrobial activity and it was selected for developing the new active packaging material. Scanning electron microscopy and Raman spectroscopy were successfully used to demonstrate the mode of action of benzyl isothiocyanate on Escherichia coli. Bacteria exhibited external modifications such as oval shape and the presence of septum surface, but they did not show any disruption or membrane damage. To provide data on the in vitro action of benzyl isothiocyanate and the presence of inhibition halos, the transfer mechanism to the cells was assessed using solid-phase microextraction-gas chromatography-mass spectrometry. Based on the transfer system, action mechanism and its stronger antimicrobial activity, benzyl isothiocyanate was incorporated to two kinds of antimicrobial labels. The labels were stable and active for 140 days against two mould producers of ochratoxin A; Penicillium verrucosum is more sensitive than Aspergillus ochraceus. Details about the analytical techniques and the results obtained are shown and discussed. Graphical Abstract Antimicrobial evaluation of pure compounds, incorporation in the packaging and study for mode of action on S. coli by Raman, SEM and SPME-GC-MS.

ANTIMICROBIAL ACTIVITY OF BURSERA MORELENSIS RAMÍREZ ESSENTIAL OIL.

PubMed

M, Canales-Martinez; C R, Rivera-Yañez; J, Salas-Oropeza; H R, Lopez; M, Jimenez-Estrada; R, Rosas-Lopez; D A, Duran; C, Flores; L B, Hernandez; M A, Rodriguez-Monroy

2017-01-01

Bursera morelensis , known as "Aceitillo", is an endemic tree of Mexico. Infusions made from the bark of this species have been used for the treatment of skin infections and for their wound healing properties. In this work, we present the results of a phytochemical and antimicrobial investigation of the essential oil of B. morelensis . The essential oil was obtained by a steam distillation method and analyzed using GC-MS. The antibacterial and antifungal activities were evaluated. GC-MS of the essential oil demonstrated the presence of 28 compounds. The principal compound of the essential oil was a-Phellandrene (32.69%). The essential oil had antibacterial activity against Gram positive and negative strains. The most sensitive strains were S. pneumoniae , V. cholerae (cc) and E. coli (MIC 0.125 mg/mL, MBC 0.25 mg/mL). The essential oil was bactericidal for V. cholera (cc). The essential oil inhibited all the filamentous fungi. F. monilifome (IC 50 = 2.27 mg/mL) was the most sensitive fungal strain. This work provides evidence that confirms the antimicrobial activity of the B. morelensis essential oil and this is a scientific support about of traditional uses of this species.

ANTIMICROBIAL ACTIVITY OF BURSERA MORELENSIS RAMÍREZ ESSENTIAL OIL

PubMed Central

M., Canales-Martinez; C.R., Rivera-Yañez; J., Salas-Oropeza; H.R., Lopez; M., Jimenez-Estrada; R., Rosas-Lopez; D.A., Duran; C., Flores; L.B., Hernandez; M.A., Rodriguez-Monroy

2017-01-01

Background: Bursera morelensis, known as “Aceitillo”, is an endemic tree of Mexico. Infusions made from the bark of this species have been used for the treatment of skin infections and for their wound healing properties. In this work, we present the results of a phytochemical and antimicrobial investigation of the essential oil of B. morelensis. Materials and Methods: The essential oil was obtained by a steam distillation method and analyzed using GC-MS. The antibacterial and antifungal activities were evaluated. Results: GC-MS of the essential oil demonstrated the presence of 28 compounds. The principal compound of the essential oil was a-Phellandrene (32.69%). The essential oil had antibacterial activity against Gram positive and negative strains. The most sensitive strains were S. pneumoniae, V. cholerae (cc) and E. coli (MIC 0.125 mg/mL, MBC 0.25 mg/mL). The essential oil was bactericidal for V. cholera (cc). The essential oil inhibited all the filamentous fungi. F. monilifome (IC50 = 2.27 mg/mL) was the most sensitive fungal strain. Conclusions: This work provides evidence that confirms the antimicrobial activity of the B. morelensis essential oil and this is a scientific support about of traditional uses of this species. PMID:28480418

Antimicrobial Resistance Among Nontyphoidal Salmonella Isolated From Blood in the United States, 2003-2013.

PubMed

Angelo, Kristina M; Reynolds, Jared; Karp, Beth E; Hoekstra, Robert Michael; Scheel, Christina M; Friedman, Cindy

2016-11-15

 Salmonella causes an estimated 100 000 antimicrobial-resistant infections annually in the United States. Salmonella antimicrobial resistance may result in bacteremia and poor outcomes. We describe antimicrobial resistance among nontyphoidal Salmonella blood isolates, using data from the National Antimicrobial Resistance Monitoring System.  Human nontyphoidal Salmonella isolates from 2003 to 2013 were classified as fully susceptible, resistant to ≥1 antimicrobial agent, or resistant to a first-line agent. Logistic regression was used to compare resistance patterns, serotypes, and patient characteristics for Salmonella isolated from blood versus stool and to determine resistance trends over time.  Approximately 20% of blood isolates had antimicrobial resistance to a first-line treatment agent. Bacteremia was associated with male sex, age ≥65 years, and specific serotypes. Blood isolates were more likely to be resistant to ≥1 agent for serotypes Enteritidis, Javiana, Panama, and Typhimurium. Blood isolates were most commonly resistant to tetracycline (19%), and more likely resistant to a first-line agent (odds ratio, 1.81; 95% confidence interval, 1.56-2.11) than stool isolates. Ceftriaxone resistance increased in blood isolates from 2003 to 2013 (odd ratio, 1.12; 95% confidence interval, 1.02-1.22).  Resistance to first-line treatment agents in patients with Salmonella bacteremia is a concern for public health and for informing clinical decisions. Judicious antimicrobial use is crucial to limit resistance. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Antimicrobial Use for and Resistance of Zoonotic Bacteria Recovered from Nonhuman Primates.

PubMed

Kim, Jeffrey; Coble, Dondrae J; Salyards, Gregory W; Bower, Julie K; Rinaldi, William J; Plauche, Gail B; Habing, Gregory G

2017-02-01

As a growing threat to human and animal health, antimicrobial resistance (AMR) has become a central public-health topic. Largescale surveillance systems, such as the National Antimicrobial Resistance Monitoring System (NARMS), are now established to monitor and provide guidance regarding AMR, but comprehensive literature on AMR among NHP is sparse. This study provides data regarding current antimicrobial use strategies and the prevalence of AMR in zoonotic bacteria recovered from NHP within biomedical research institutions. We focused on 4 enteric bacteria: Shigella flexneri, Yersinia enterocolitica, Y. pseudotuberculosis, and Campylobacter jejuni. Fifteen veterinarians, 7 biomedical research institutions, and 4 diagnostic laboratories participated, providing susceptibility test results from January 2012 through April 2015. Veterinarians primarily treated cases caused by S. flexneri, Y. enterocolitica, and Y. pseudotuberculosis with enrofloxacin but treated C. jejuni cases with azithromycin and tylosin. All isolates were susceptible to the associated primary antimicrobial but often showed resistance to others. Specifically, S. flexneri isolates frequently were resistant to erythromycin (87.5%), doxycycline (73.7%), and tetracycline (38.3%); Y. enterocolitica isolates to ampicillin (100%) and cefazolin (93.6%); and C. jejuni isolates to methicillin (99.5%) and cephalothin (97.5%). None of the 58 Y. pseudotuber-culosis isolates was resistant to any tested antimicrobial. Notably, resistance patterns were not shared between this study's NHP isolates and human isolates presented by NARMS. Our findings indicate that zoonotic bacteria from NHP diagnostic samples are broadly susceptible to the antimicrobials used to treat the clinical infections. These results can help veterinarians ensure effective antimicrobial therapy and protect staff by minimizing occupational risk.

Antimicrobial Use for and Resistance of Zoonotic Bacteria Recovered from Nonhuman Primates

PubMed Central

Kim, Jeffrey; Coble, Dondrae J; Salyards, Gregory W; Bower, Julie K; Rinaldi, William J; Plauche, Gail B; Habing, Gregory G

2017-01-01

As a growing threat to human and animal health, antimicrobial resistance (AMR) has become a central public-health topic. Large-scale surveillance systems, such as the National Antimicrobial Resistance Monitoring System (NARMS), are now established to monitor and provide guidance regarding AMR, but comprehensive literature on AMR among NHP is sparse. This study provides data regarding current antimicrobial use strategies and the prevalence of AMR in zoonotic bacteria recovered from NHP within biomedical research institutions. We focused on 4 enteric bacteria: Shigella flexneri, Yersinia enterocolitica, Y. pseudotuberculosis, and Campylobacter jejuni. Fifteen veterinarians, 7 biomedical research institutions, and 4 diagnostic laboratories participated, providing susceptibility test results from January 2012 through April 2015. Veterinarians primarily treated cases caused by S. flexneri, Y. enterocolitica, and Y. pseudotuberculosis with enrofloxacin but treated C. jejuni cases with azithromycin and tylosin. All isolates were susceptible to the associated primary antimicrobial but often showed resistance to others. Specifically, S. flexneri isolates frequently were resistant to erythromycin (87.5%), doxycycline (73.7%), and tetracycline (38.3%); Y. enterocolitica isolates to ampicillin (100%) and cefazolin (93.6%); and C. jejuni isolates to methicillin (99.5%) and cephalothin (97.5%). None of the 58 Y. pseudotuberculosis isolates was resistant to any tested antimicrobial. Notably, resistance patterns were not shared between this study's NHP isolates and human isolates presented by NARMS. Our findings indicate that zoonotic bacteria from NHP diagnostic samples are broadly susceptible to the antimicrobials used to treat the clinical infections. These results can help veterinarians ensure effective antimicrobial therapy and protect staff by minimizing occupational risk. PMID:28222842

A review of the factors influencing antimicrobial prescribing.

PubMed

Calbo, Esther; Alvarez-Rocha, Luis; Gudiol, Francisco; Pasquau, Juan

2013-09-01

There are multiple benefits of appropriate antimicrobial prescribing: it has a direct impact on clinical outcomes, avoids adverse effects, is cost effective and, perhaps most importantly, it helps to prevent the emergence of resistance. However, any physician can prescribe antibiotics, which is not the case with other clinically relevant drugs. There is great variability in the prescribing physician's (PP) training, motivation, workload and setting, including accessibility to infectious diseases consultants and/or diagnostic techniques, and therefore there is a high risk of inappropriate prescription. Many antibiotic prescribing errors occur around the selection and duration of treatment. This includes a low threshold for the indication of antibiotics, delayed initiation of treatment when indicated, limited knowledge of local antimicrobial resistance patterns by the PPs, errors in the final choice of dose, route or drug and a lack of de-escalation. Similarly, the prescription of prophylactic antibiotics to prevent surgical site infections, despite being commonly accepted, is suboptimal. Factors that may explain suboptimal use are related to the absence of well-defined protocols, poor knowledge of prophylactic protocols, miscommunication or disagreement between physicians, logistical problems, and a lack of audits. A proper understanding of the prescribing process can guide interventions to improve the PP's practices. Some of the potential interventions included in a stewardship program are education in antimicrobial prescribing, information on the local resistance patterns and accessibility to a qualified infectious diseases consultant. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Bloodstream Infections in Hospitalized Children: Epidemiology and Antimicrobial Susceptibilities.

PubMed

Larru, Beatriz; Gong, Wu; Vendetti, Neika; Sullivan, Kaede V; Localio, Russell; Zaoutis, Theoklis E; Gerber, Jeffrey S

2016-05-01

Bloodstream infection is a major cause of morbidity and mortality. Much of our understanding of the epidemiology and resistance patterns of bloodstream infections comes from studies of hospitalized adults. We evaluated the epidemiology and antimicrobial resistance of bloodstream infections occurring during an 11-year period in a large, tertiary care children's hospital in the US. All positive blood cultures were identified retrospectively from clinical microbiology laboratory records. We excluded repeat positive cultures with the same organism from the same patient within 30 days and polymicrobial infections. We identified 8196 unique episodes of monomicrobial bacteremia in 5508 patients. Overall, 46% were community onset, 72% were Gram-positive bacteria, 22% Gram-negative bacteria and 5% Candida spp. Coagulase negative Staphylococcus was the most common isolated organism. ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) accounted for 20% of episodes. No S. aureus isolate was resistant to vancomycin or linezolid, and no increase in vancomycin minimum inhibitory concentration among methicillin-resistant S. aureus was observed during the study period. Clinically significant increases in vancomycin-resistant Enterococcus, ceftazidime-resistant P. aeruginosa or carbapenem-resistant Enterobacteriaceae were not observed during the study period; however, rates of methicillin-resistant S. aureus increased over time (P < 0.01). Gram-positive and ESKAPE organisms are leading causes of bacteremia in hospitalized children. Although antimicrobial resistance patterns were favorable compared with prior reports of hospitalized adults, multicenter studies with continuous surveillance are needed to identify trends in the emergence of antimicrobial resistance in this setting.

Antimicrobial Resistance Genes in Pigeons from Public Parks in Costa Rica.

PubMed

Blanco-Peña, K; Esperón, F; Torres-Mejía, A M; de la Torre, A; de la Cruz, E; Jiménez-Soto, M

2017-11-01

Antimicrobial resistance is known to be an emerging problem, but the extent of the issue remains incomplete. The aim of this study was to determine the presence or absence of nine resistance genes (bla TEM , catI, mecA, qnrS, sulI, sulII, tet(A), tet(Q), vanA) in the faeces of 141 pigeons from four urban parks in Alajuela, Guadalupe, Tres Ríos and San José in Costa Rica. The genes were identified by real-time PCR directly from enema samples. About 30% of the samples were positive for genes catI and sulI; between 13% and 17% were positive for qnrS, sulII, tet(A) and tet(Q); and 4% were positive for bla TEM . The mecA and vanA genes were not detected. The average of antimicrobial resistance genes detected per pigeon was 2. Eight different patterns of resistance were identified, without differences in the sampling areas, being the most common pattern 2 (sulII positive samples). During rainy season, the genes more frequently found were sulI and tet(A). In conclusion, the urban inhabiting pigeons tested are currently carrying antimicrobial resistance genes, potentially acting as reservoirs of resistant bacteria and vectors to humans. To the authors' knowledge, this is the first study carried out on direct detection of resistance genes in the digestive metagenomes of pigeons. © 2017 The Authors. Zoonoses and Public Health Published by Blackwell Verlag GmbH.

[Comparative effectiveness of antimicrobial action of antiseptics against pathogens of chronic purulent otitis media].

PubMed

Paliĭ, G K; Barilo, A S; Chesnokova, A A

1992-12-01

Comparable antimicrobial and disinfecting action of decamethoxine and silver preparations on pathogens of chronic purulent otitis media (CPOM) was studied. The clinical isolates of staphylococci proved to be most sensitive to decamethoxine whose MBcC conformed to 16.5 micrograms/ml. The antimicrobial action on Proteus spp. and Pseudomonas aeruginosa was less pronounced. The required concentrations for bactericidal action on these pathogens were 69 and 93.5 micrograms/ml, respectively. The antimicrobial activity of the silver preparations such as poviargol, collargol and protargol was low. Depending on the microbial species, the bactericidal effect of the silver preparations was 12-235 times lower than that of decamethoxin. It was also shown that decamethoxin had a high disinfecting action on CPOM pathogens. It was noted that decamethoxin had a marked ability to increase the bactericidal action of poviargol (by 2-14 times) and its disinfecting action (by 2 times) on Proteus spp., E. coli and Ps. aeruginosa.

Antimicrobial resistance in Campylobacter spp isolated from broiler flocks

PubMed Central

Kuana, Suzete Lora; dos Santos, Luciana Ruschel; Rodrigues, Laura Beatriz; Borsoi, Anderlise; Moraes, Hamilton Luis do Souza; Salle, Carlos Tadeu Pippi; do Nascimento, Vladimir Pinheiro

2008-01-01

The aim of this study was to assess the antimicrobial susceptibility of 62 Campylobacter spp. strains obtained from broiler flocks using the agar diffusion method. The Campylobacter spp strains were isolated from 22 flocks aged between 3 and 5 weeks of life, isolated from cloacae swabs, stools and cecal droppings in the farm and from the carcass rinsing in the slaughterhouse. Campylobacter spp strains were tested on Mueller-Hilton (MH) agar (27 samples) and MH plus TTC agar (35 samples). The antimicrobial susceptibility test revealed a 62.5% resistance to at least one drug, especially to enrofloxacin (71%), neomycin (50%), lincomycin (50%), tetracycline (43%), penicillin (42%), ceftiofur (33%) amoxicillin (27%), spiramycin (20%), ampicillin (18%) and norfloxacin (14%), whereas a lower percentage of strains was resistant to erythromycin (10%) and doxycycline (10%). All strains were sensitive to gentamicin and lincomycin-spectinomycin and 80% of them to colistin. These results indicate that it is necessary to reduce the use of antimicrobials in veterinary and human medicine. PMID:24031299

Fitness benefits in fluoroquinolone-resistant Salmonella Typhi in the absence of antimicrobial pressure

PubMed Central

Baker, Stephen; Duy, Pham Thanh; Nga, Tran Vu Thieu; Dung, Tran Thi Ngoc; Phat, Voong Vinh; Chau, Tran Thuy; Turner, A Keith; Farrar, Jeremy; Boni, Maciej F

2013-01-01

Fluoroquinolones (FQ) are the recommended antimicrobial treatment for typhoid, a severe systemic infection caused by the bacterium Salmonella enterica serovar Typhi. FQ-resistance mutations in S. Typhi have become common, hindering treatment and control efforts. Using in vitro competition experiments, we assayed the fitness of eleven isogenic S. Typhi strains with resistance mutations in the FQ target genes, gyrA and parC. In the absence of antimicrobial pressure, 6 out of 11 mutants carried a selective advantage over the antimicrobial-sensitive parent strain, indicating that FQ resistance in S. Typhi is not typically associated with fitness costs. Double-mutants exhibited higher than expected fitness as a result of synergistic epistasis, signifying that epistasis may be a critical factor in the evolution and molecular epidemiology of S. Typhi. Our findings have important implications for the management of drug-resistant S. Typhi, suggesting that FQ-resistant strains would be naturally maintained even if fluoroquinolone use were reduced. DOI: http://dx.doi.org/10.7554/eLife.01229.001 PMID:24327559

In Vitro Evaluation of Antimicrobial Activity of Alimentary Canal Extracts from the Red Palm Weevil, Rhynchophorus ferrugineus Olivier Larvae.

PubMed

Sewify, Gamal H; Hamada, Hanan M; Alhadrami, Hani A

2017-01-01

The invasive red palm weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae), is considered one of the world's most devastating insect pests to palm trees. It was observed that larvae of this pest are able to inhibit microbial growth on the rearing media when they start feeding and this observation has led us to study the effect of red palm weevils on various microbial species. The antimicrobial effect of extracts from different parts of the alimentary canal on Gram positive bacteria ( Enterococcus faecalis and Staphylococcus aureus ), Gram negative bacteria ( Escherichia coli and Klebsiella spp.), Candida albicans, and Penicillium sp. was tested using the agar well diffusion method. All extracts inhibited the tested microbial species. Foregut extracts had the greatest zones of growth inhibition. Enterococcus faecalis , Staphylococcus aureus, and Penicillium sp. were significantly sensitive to the extracts and had the largest growth inhibition zones. It is concluded that the gut extracts contain potent antimicrobial activity and may provide a new source of antimicrobial peptides.

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.

Changes in antimicrobial susceptibility profile and prevalence of quinolone low-sensitive strains in subgingival plaque from acute periodontal lesions after systemic administration of sitafloxacin.

PubMed

Tomita, Sachiyo; Kasai, Shunsuke; Imamura, Kentaro; Ihara, Yuichiro; Kita, Daichi; Ota, Koki; Sekino, Jin; Nakagawa, Taneaki; Saito, Atsushi

2015-02-01

This study aimed to assess changes in antimicrobial susceptibilities of subgingival bacteria in acute periodontal lesions following systemic administration of a new-generation fluoroquinolone, sitafloxacin and to monitor the occurrence and fate of quinolone low-sensitive strains. Patients with acute phase of chronic periodontitis were subjected to microbiological assessment of their subgingival plaque samples at baseline (A1). Sitafloxacin was then administered systemically (100 mg/day for 5 days). The microbiological examinations were repeated one week after administration (A2). Susceptibilities of clinical isolates from acute sites to various antimicrobials were determined using broth and agar dilution methods. At A2, subgingival bacteria with low sensitivity to levofloxacin were identified in four patients, and they were subjected to a follow-up microbiological examination at on the average 12 months after sitafloxacin administration (A3). The patients received initial and supportive periodontal therapy during the period A2 to A3. From the examined subgingival sites, 8 and 19 clinical isolates were obtained at A2 and A3, respectively. Some Streptococcus strains isolated at A2 were found to be resistant to levofloxacin (MIC 16-64 μg/ml), azithromycin (MIC 2->128 μg/ml) or clarithromycin (MIC 1->32 μg/ml). At A3, isolated streptococci were highly susceptible to levofloxacin (MIC 0.5-2 μg/ml), while those resistant to azithromycin or clarithromycin were still isolated. It is suggested that the presence of the quinolone low-sensitive strains in initially acute lesions after sitafloxacin administration was transient, and they do not persist in the subgingival milieu during the periodontal therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Coagulase-Positive Staphylococcus: Prevalence and Antimicrobial Resistance.

PubMed

Beça, Nuno; Bessa, Lucinda Janete; Mendes, Ângelo; Santos, Joana; Leite-Martins, Liliana; Matos, Augusto J F; da Costa, Paulo Martins

2015-01-01

Staphylococcus pseudintermedius is the most prevalent coagulase-positive Staphylococcus inhabitant of the skin and mucosa of dogs and cats, causing skin and soft tissue infections in these animals. In this study, coagulase-positive Staphylococcus species were isolated from companion animals, veterinary professionals, and objects from a clinical veterinary environment by using two particular culture media, Baird-Parker RPF agar and CHROMagar Staph aureus. Different morphology features of colonies on the media allowed the identification of the species, which was confirmed by performing a multiplex polymerase chain reaction (PCR). Among 23 animals, 15 (65.2%) harbored coagulase-positive Staphylococcus, being 12 Staphylococcus pseudintermedius carriers. Four out of 12 were methicillin-resistant S. pseudintermedius (MRSP). All veterinary professionals had coagulase-positive Staphylococcus (CoPS) species on their hands and two out of nine objects sampled harbored MRSP. The antimicrobial-resistance pattern was achieved for all isolates, revealing the presence of many multidrug-resistant CoPS, particularly S. pseudintermedius . The combined analysis of the antimicrobial-resistance patterns shown by the isolates led to the hypothesis that there is a possible crosscontamination and dissemination of S. aureus and S. pseudintermedius species between the three types of carriers sampled in this study that could facilitate the spread of the methicillin-resistance phenotype.

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.

Shigella species epidemiology and antimicrobial susceptibility: the implications of emerging azithromycin resistance for guiding treatment, guidelines and breakpoints.

PubMed

Brown, Jeremy D; Willcox, Simon J; Franklin, Neil; Hazelton, Briony; Howard, Peter; Reinten, Tracie; Sheppeard, Vicky; O'Sullivan, Matthew

2017-11-01

To examine antimicrobial susceptibility patterns and predictors of resistance among Shigella isolates in New South Wales (NSW), Australia during 2013-14 with emphasis on azithromycin. Cross-sectional analysis of all shigellosis cases (160) notified to public health authorities in NSW, Australia was performed. Among 160 Shigella isolates tested, 139 (86.9%) were susceptible to azithromycin, 104 (65.0%) to ciprofloxacin and 38 (23.7%) to co-trimoxazole. Ciprofloxacin resistance was 1.9 times more common in infections acquired in Australia compared with those acquired overseas, while azithromycin resistance was 8.5 times more common in males. We recommend ongoing reconsideration of guidelines for the treatment of shigellosis based on emerging resistance patterns. First-line therapy may need to be reconsidered based on local resistance rates due to common resistance to co-trimoxazole and ciprofloxacin. We recommend culture and susceptibility testing for suspected and proven shigellosis. Azithromycin susceptibility breakpoints for Shigella species may need to be species specific. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Incidence of bovine clinical mastitis in Jammu region and antibiogram of isolated pathogens.

PubMed

Bhat, Adil Majid; Soodan, Jasvinder Singh; Singh, Rajiv; Dhobi, Ishfaq Ahmad; Hussain, Tufail; Dar, Mohammad Yousuf; Mir, Muheet

2017-08-01

This study was conducted to evaluate the incidence of clinical mastitis in bovines of Jammu region, to identify the infectious organisms responsible for it, and the antimicrobial sensitivity of isolated pathogens. The study was conducted on cases that were presented to the Medicine Division of Teaching Veterinary Clinical Complex, Faculty of Veterinary Sciences and Animal Husbandry, R.S. Pura, Jammu, Jammu and Kashmir. A total of 260 cases of bovines were presented from June 30, 2012, to July 01, 2013, out of which 30 cases were of clinical mastitis. The diagnosis of clinical mastitis was made on the basis of history and clinical examination of affected animals. Animal and quarter-wise incidence of clinical mastitis were found to be 11.5% and 5.76%, respectively. Of the 23 isolates obtained, Staphylococcus aureus (60.87%) was the most frequently isolated organism, followed by coagulase negative Staphylococci (13.04%), Streptococcus uberis (4.35%), Streptococcus dysgalactiae (8.69%), and Escherichia coli (13.04%). The antimicrobial sensitivity of isolates revealed maximum sensitivity to enrofloxacin, gentamicin, amoxicillin/sulbactam, ceftriaxone/tazobactam, ceftizoxime, ampicillin/sulbactam and least sensitivity for oxytetracycline and penicillin. Staphylococcus spp. is the major causative agent of clinical mastitis in bovines of Jammu region. The causative agents of the clinical mastitis were most sensitive to enrofloxacin and gentamicin.

Improving antimicrobial prescribing in Irish primary care through electronic data collection and surveillance: a feasibility study.

PubMed

Galvin, Sandra; Callan, Aoife; Cormican, Martin; Duane, Sinead; Bennett, Kathleen; Murphy, Andrew W; Vellinga, Akke

2015-07-02

The increase in the spread of antimicrobial resistance (AMR) in bacterial pathogens and limited availability of new antimicrobials places immense pressure on general practitioners (GPs) to prescribe appropriately. Currently, electronic antimicrobial prescribing data is not routinely collected from GPs in Ireland for surveillance purposes to assess regional specific fluctuations or trends in antimicrobial prescribing. The current study aimed to address this issue by assessing the feasibility of remotely extracting antimicrobial prescribing data from primary care practices in Ireland, for the purpose of assessing prescribing quality using the European Surveillance of Antimicrobial Consumption (ESAC) drug specific quality indicators. Participating practices (n = 30) uploaded data to the Irish Primary Care Research Network (IPCRN). The IPCRN data extraction facility is integrated within the practice patient management software system and permitted the extraction of anonymised patient prescriptions for a one year period, from October 2012 to October 2013. The quality of antimicrobial prescribing was evaluated using the twelve ESAC drug specific quality indicators using the defined daily dose (DDD) per 1,000 inhabitants per day (DID) methodology. National and European prescribing surveillance data (based on total pharmacy sales) was obtained for a comparative analysis. Antimicrobial prescriptions (n = 57,079) for 27,043 patients were obtained from the thirty study practices for a one year period. On average, study practices prescribed a greater proportion of quinolones (37 % increase), in summer compared with winter months, a variation which was not observed in national and European data. In comparison with national data, study practices prescribed higher proportions of β-lactamase-sensitive penicillins (4.98 % vs. 4.3 %) and a greater use of broad spectrum compared to narrow-spectrum antimicrobials (ratio = 9.98 vs. 6.26) was observed. Study practices exceeded the European mean for prescribing combinations of penicillins, including β-lactamase inhibitors. This research demonstrates the feasibility and potential use of direct data extraction of anonymised practice data directly through the patient management software system. The data extraction methods described can facilitate the provision of routinely collected data for sustained and inclusive surveillance of antimicrobial prescribing. These comparisons may initiate further improvements in antimicrobial prescribing practices by identifying potential areas for improvement.

Stenotrophomonas maltophilia is highly prevalent among houseflies (Musca domestica).

PubMed

Fukuda, Akira; Usui, Masaru; Wakao, Hideyuki; Boonla, Chanchai; Tamura, Yutaka

2017-08-04

Stenotrophomonas maltophilia is capable of surviving in a wide variety of environments and is considered to be among the antimicrobial-resistant bacteria of greatest public health concern in hospital settings. To clarify the role of houseflies (Musca domestica) in disseminating this bacterium, we collected 99 individuals from 15 locations (9 farms and 6 urban areas) in Thailand. S. maltophilia was isolated from 39 % (39/99) of these houseflies, with the isolation rates being similar in farms and urban areas. Multiple-antimicrobial resistance was evident among the S. maltophilia isolates obtained. Of note, the rate of resistance to trimethoprim/sulfamethoxazole (TMP/SMX), the recommended first-line antimicrobial for S. maltophilia infection, was relatively high (30 %). Almost all of the isolates had a different PFGE pattern. These results suggest that houseflies ingest and host S. maltophilia from several different environmental sources. In conclusion, houseflies may facilitate the spread of antimicrobial-resistant (including TMP/SMX-resistant) S. maltophilia from environmental sources to humans.

Biosynthesis of silver nanoparticles using Plectranthus amboinicus leaf extract and its antimicrobial activity

NASA Astrophysics Data System (ADS)

Ajitha, B.; Ashok Kumar Reddy, Y.; Sreedhara Reddy, P.

2014-07-01

This study reports the simple green synthesis method for the preparation of silver nanoparticles (Ag NPs) using Plectranthus amboinicus leaf extract. The pathway of nanoparticles formation is by means of reduction of AgNO3 by leaf extract, which acts as both reducing and capping agents. Synthesized Ag NPs were subjected to different characterizations for studying the structural, chemical, morphological, optical and antimicrobial properties. The bright circular fringes in SAED pattern and diffraction peaks in XRD profile reveals high crystalline nature of biosynthesized Ag NPs. Morphological studies shows the formation of nearly spherical nanoparticles. FTIR spectrum confirms the existence of various functional groups of biomolecules capping the nanoparticles. UV-visible spectrum displays single SPR band at 428 nm indicating the absence of anisotropic particles. The synthesized Ag NPs exhibited better antimicrobial property towards gram negative Escherichia coli and towards tested Penicillium spp. than other tested microorganisms using disc diffusion method. Finally it has proven that the synthesized bio-inspired Ag NPs have potent antimicrobial effect.

Biosynthesis of silver nanoparticles by Novosphingobium sp. THG-C3 and their antimicrobial potential.

PubMed

Du, Juan; Singh, Hina; Yi, Tae-Hoo

2017-03-01

The present study described biosynthesis of silver nanoparticles (AgNPs) using a bacterial strain Novosphingobium sp. THG-C3, isolated from soil, and their application in antibacterial activity. The maximum absorbance values of the synthesized AgNPs was measured at 406 nm in ultraviolet-visible spectrophotometry and were mostly spherical in shape with particle size in range of 8-25 nm by field emission transmission electron microscopy analysis. X-ray diffraction pattern corresponding to planes (111), (200), (220), and (311) demonstrated the crystalline nature of the AgNPs. The synthesized AgNPs exhibited antimicrobial activity against various pathogens inculding Staphylococcus aureus, Candida tropicalis, Pseudomonas aeruginosa, Escherichia coli, Vibrio parahaemolyticus, Candida albicans, Salmonella enterica, Bacillus subtilis, and Bacillus cereus. In addition, the AgNPs in combination with commercial antibiotics enhanced antimicrobial activity against P. aeruginosa, S. enterica, E. coli, and V. parahaemolyticus. The AgNPs synthesized by strain Novosphingobium sp. THG-C3 are comparatively simple, green, cost-effective, and may serve as a potential antimicrobial agent.

Conventional and molecular diagnostic strategies for prosthetic joint infections.

PubMed

Esteban, Jaime; Sorlí, Luisa; Alentorn-Geli, Eduard; Puig, Lluís; Horcajada, Juan P

2014-01-01

An accurate diagnosis of prosthetic joint infection (PJI) is the mainstay for an optimized clinical management. This review analyzes different diagnostic strategies of PJI, with special emphasis on molecular diagnostic tools and their current and future applications. Until now, the culture of periprosthetic tissues has been considered the gold standard for the diagnosis of PJI. However, sonication of the implant increases the sensitivity of those cultures and is being increasingly adopted by many centers. Molecular diagnostic methods compared with intraoperative tissue culture, especially if combined with sonication, have a higher sensitivity, a faster turnaround time and are not influenced by previous antimicrobial therapy. However, they still lack a system for detection of antimicrobial susceptibility, which is crucial for an optimized and less toxic therapy of PJI. More studies are needed to assess the clinical value of these methods and their cost-effectiveness.

Reliability of three bulk-tank antimicrobial residue detection assays used to test individual milk samples from cows with mild clinical mastitis.

PubMed

Gibbons-Burgener, S N; Kaneene, J B; Lloyd, J W; Leykam, J F; Erskine, R J

2001-11-01

To determine the likelihood of false-positive results when testing milk samples from individual cows by use of 3 commercially available assays (Penzyme MilkTest and the SNAP beta-lactam and Delvo-SP assays) labeled for use with commingled milk. Milk samples from 111 cows with mild clinical mastitis. Cows were randomly assigned to the control (no antimicrobials) or intramammary treatment group. Posttreatment milk samples were collected at the first milking after the labeled withholding period or an equivalent time for controls, randomly ordered, and tested twice by use of each assay and once by use of high-performance liquid chromatography. Sensitivity, specificity, and positive and negative predictive values were determined for each assay. Concordance of results for the same sample was assessed for each assay by calculating kappa. Sensitivities of the Delvo-SP and SNAP lactam assays were > 90%, whereas the sensitivity of the Penzyme Milk Test was 60%. Positive predictive values (range, 39.29 to 73.68%) were poor for all 3 assays. Concordance of test results was excellent for the SNAP beta-lactam and Delvo-SP assays (kappa = 0.846 and 0.813, respectively) but was less for the Penzyme MilkTest (kappa = 0.545). Because of the low positive predictive values, these 3 assays may not be useful for detecting violative antimicrobial residues in individual milk samples from cows treated for mild clinical mastitis. However, repeatability of each assay was considered good to excellent.

In vitro antimicrobial activity of Pistacia lentiscus L. edible oil and phenolic extract.

PubMed

Mezni, F; Aouadhi, C; Khouja, M L; Khaldi, A; Maaroufi, A

2015-01-01

Pistacia lentiscus L. is known in some Tunisian forest area by its fixed oil used in traditional medicine as an antiseptic product. This investigation is the first to study the antimicrobial activity of P.lentiscus edible oil and its phenolic extract. Oil was extracted from fruits harvested from six provenances located in Tunisia. The antimicrobial activity was tested using disc diffusion assay and the broth dilution method. Kbouch and Sidi Zid oils were most efficient (p < 0.003) against, respectively, Staphylococcus aureus and Aspergillus niger with an inhibition zone of 9.33 mm. The phenolic extract had the largest spectrum of sensitive microorganisms. The minimum inhibitory concentration and minimum bactericidal concentration results showed that all strains were inhibited by both oil and extract.

Antimicrobial Nanomaterials Derived from Natural Products—A Review

PubMed Central

Wang, Ji; Vermerris, Wilfred

2016-01-01

Modern medicine has relied heavily on the availability of effective antibiotics to manage infections and enable invasive surgery. With the emergence of antibiotic-resistant bacteria, novel approaches are necessary to prevent the formation of biofilms on sensitive surfaces such as medical implants. Advances in nanotechnology have resulted in novel materials and the ability to create novel surface topographies. This review article provides an overview of advances in the fabrication of antimicrobial nanomaterials that are derived from biological polymers or that rely on the incorporation of natural compounds with antimicrobial activity in nanofibers made from synthetic materials. The availability of these novel materials will contribute to ensuring that the current level of medical care can be maintained as more bacteria are expected to develop resistance against existing antibiotics. PMID:28773379

Antimicrobial nanomaterials derived from natural products—A review

DOE PAGES

Wang, Ji; Vermerris, Wilfred

2016-03-30

Modern medicine has relied heavily on the availability of effective antibiotics to manage infections and enable invasive surgery. With the emergence of antibiotic-resistant bacteria, novel approaches are necessary to prevent the formation of biofilms on sensitive surfaces such as medical implants. Advances in nanotechnology have resulted in novel materials and the ability to create novel surface topographies. This review article provides an overview of advances in the fabrication of antimicrobial nanomaterials that are derived from biological polymers or that rely on the incorporation of natural compounds with antimicrobial activity in nanofibers made from synthetic materials. Furthermore, the availability of thesemore » novel materials will contribute to ensuring that the current level of medical care can be maintained as more bacteria are expected to develop resistance against existing antibiotics.« less

Antimicrobial nanomaterials derived from natural products—A review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Ji; Vermerris, Wilfred

Modern medicine has relied heavily on the availability of effective antibiotics to manage infections and enable invasive surgery. With the emergence of antibiotic-resistant bacteria, novel approaches are necessary to prevent the formation of biofilms on sensitive surfaces such as medical implants. Advances in nanotechnology have resulted in novel materials and the ability to create novel surface topographies. This review article provides an overview of advances in the fabrication of antimicrobial nanomaterials that are derived from biological polymers or that rely on the incorporation of natural compounds with antimicrobial activity in nanofibers made from synthetic materials. Furthermore, the availability of thesemore » novel materials will contribute to ensuring that the current level of medical care can be maintained as more bacteria are expected to develop resistance against existing antibiotics.« less

Beta-Lactamase Repressor BlaI Modulates Staphylococcus aureus Cathelicidin Antimicrobial Peptide Resistance and Virulence.

PubMed

Pence, Morgan A; Haste, Nina M; Meharena, Hiruy S; Olson, Joshua; Gallo, Richard L; Nizet, Victor; Kristian, Sascha A

2015-01-01

BlaI is a repressor of BlaZ, the beta-lactamase responsible for penicillin resistance in Staphylococcus aureus. Through screening a transposon library in S. aureus Newman for susceptibility to cathelicidin antimicrobial peptide, we discovered BlaI as a novel cathelicidin resistance factor. Additionally, through integrational mutagenesis in S. aureus Newman and MRSA Sanger 252 strains, we confirmed the role of BlaI in resistance to human and murine cathelidicin and showed that it contributes to virulence in human whole blood and murine infection models. We further demonstrated that BlaI could be a target for innate immune-based antimicrobial therapies; by removing BlaI through subinhibitory concentrations of 6-aminopenicillanic acid, we were able to sensitize S. aureus to LL-37 killing.

The livestock reservoir for antimicrobial resistance: a personal view on changing patterns of risks, effects of interventions and the way forward

PubMed Central

Aarestrup, Frank M.

2015-01-01

The purpose of this review was to provide an updated overview on the use of antimicrobial agents in livestock, the associated problems for humans and current knowledge on the effects of reducing resistance in the livestock reservoir on both human health and animal production. There is still limiting data on both use of antimicrobial agents, occurrence and spread of resistance as well as impact on human health. However, in recent years, emerging issues related to methicillin-resistant Staphylococcus aureus, Clostridium difficile, Escherichia coli and horizontally transferred genes indicates that the livestock reservoir has a more significant impact on human health than was estimated 10 years ago, where the focus was mainly on resistance in Campylobacter and Salmonella. Studies have indicated that there might only be a marginal if any benefit from the regular use of antibiotics and have shown that it is possible to substantially reduce the use of antimicrobial agents in livestock production without compromising animal welfare or health or production. In some cases, this should be done in combination with other measures such as biosecurity and use of vaccines. To enable better studies on both the global burden and the effect of interventions, there is a need for global harmonized integrated and continuous surveillance of antimicrobial usage and antimicrobial resistance, preferably associated with data on production and animal diseases to determine the positive and negative impact of reducing antimicrobial use in livestock. PMID:25918442

Current Trends of Using Antimicrobial Drugs in the ICU at a Tertiary Level Teaching Hospital in Mymensingh.

PubMed

Saha, S K; Shaha, K C; Haque, M F; Khatun, S; Akhter, S M; Akhter, H

2016-10-01

The aim of the present study was to investigate the current trends of using antimicrobial drugs in the ICU at a tertiary level teaching hospital in Mymensingh. The study of prescribing patterns seeks to monitor, evaluate and suggest modifications in clinicians prescribing habits so as to make medical care rational. It was an observational type of descriptive study, conducted in the Mymensingh medical college hospital, Mymensingh, during the study period of June 2016 to September 2016.The study was approved by the institutional ethical committee. Most patients in the ICU belonged to the older age group >60 years. Male patients were more than the female patients in ICU. Average duration of stay in ICU was 4.35 days. Admissions in ICU were common due to respiratory system related diseases and the present study showed that 31.68% of the reported cases belong to the respiratory system. Average number of drugs per prescription was 6.46. Average number of anti-microbial drugs per prescription was 1.38. Cephalosporin group and individually ceftriaxone was the most frequently prescribed antimicrobial group and agent respectively in the ICU. Most commonly used antimicrobial combination was Cephalosporin and Metronidazole (43.33%) followed by Carbapenem (Meropenem) and Metronidazole (13.33%). Most antimicrobial agents were prescribed without bacteriological culture and sensivity testing evidence. There is a need for motivating the physicians to prescribe antimicrobial agents with supportive bacteriological evidences.

Anti-microbial screening and cytotoxic activity of aerial part of Thymelaea hirsuta L. essential oil growing in south-west Tunisia.

PubMed

Felhi, Samir; Chaaibia, Mouna; Bakari, Sana; Mansour, Riadh Ben; Békir, Ahmed; Gharsallah, Néji; Kadri, Adel

2017-01-01

This study aimed to investigate the antimicrobial and cytotoxic activities of essential oil isolated by the hydro-distillation of aerial parts of Thymelaea hirsuta. The antimicrobial activity of the oil was evaluated against eight bacterial and three fungal pathogenic strains. The results revealed that the essential oil exhibited a moderate-to-potent anti-microbial activity against all the microorganisms tested. Gram-positive bacteria were noted to be more sensitive to the oil than gram-negative bacteria and yeasts. In vitro cytotoxicity evaluation against HeLa cell lines showed that the essential oil exhibited moderate cytotoxicity on human tumor cells, with a high IC 50 value of 175μg/mL. To the author's knowledge, this is the first study reporting on the antimicrobial and cytotoxic activities of Thymelaea hirsuta essential oil. Overall, the results indicate that the T. hirsuta essential oil has a number of attractive properties that might open new promising opportunities for the control or prevention of a wide range of microbial infections and cancers and can facilitate the use of essential oils as natural preservatives against spoilage microorganisms in food systems.

Binary Colloidal Crystal Layers as Platforms for Surface Patterning of Puroindoline-Based Antimicrobial Peptides.

PubMed

Boden, Andrew; Bhave, Mrinal; Wang, Peng-Yuan; Jadhav, Snehal; Kingshott, Peter

2018-01-24

The ability of bacteria to form biofilms and the emergence of antibiotic-resistant strains have prompted the need to develop the next generation of antibacterial coatings. Antimicrobial peptides (AMPs) are showing promise as molecules that can address these issues, especially if used when immobilized as a surface coating. We present a method that explores how surface patterns together with the selective immobilization of an AMP called PuroA (FPVTWRWWKWWKG-NH 2 ) can be used to both kill bacteria and also as a tool to study bacterial attachment mechanisms. Surface patterning is achieved using stabilized self-assembled binary colloidal crystal (BCC) layers, allowing selective PuroA immobilization to carboxylated particles using N-(3-dimethylaminopropyl)-N'-ethyl carbodiimide (EDC) hydrochloride/N-hydroxysuccinimide (NHS) coupling chemistry. Covalent immobilization of PuroA was compared with physical adsorption (i.e., without the addition of EDC/NHS). The AMP-functionalized colloids and BCC layers were characterized by X-ray photoelectron spectroscopy, ζ potentials, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Surface antimicrobial activity was assessed by viability assays using Escherichia coli. MALDI-TOF MS analysis revealed that although not all of PuroA was successfully covalently immobilized, a relatively low density of PuroA (1.93 × 10 13 molecules/cm 2 and 7.14 × 10 12 molecules/cm 2 for covalent and physical immobilization, respectively) was found to be sufficient at significantly decreasing the viability of E. coli by 70% when compared to that of control samples. The findings provide a proof of concept that BCC layers are a suitable platform for the patterned immobilization of AMPs and the importance of ascertaining the success of small-molecule grafting reactions using surface-MALDI, something that is often assumed to be successful in the field.

Shigellosis in Bay of Bengal Islands, India: clinical and seasonal patterns, surveillance of antibiotic susceptibility patterns, and molecular characterization of multidrug-resistant Shigella strains isolated during a 6-year period from 2006 to 2011.

PubMed

Bhattacharya, D; Bhattacharya, H; Thamizhmani, R; Sayi, D S; Reesu, R; Anwesh, M; Kartick, C; Bharadwaj, A P; Singhania, M; Sugunan, A P; Roy, S

2014-02-01

This study aims to determine the clinical features and seasonal patterns associated with shigellosis, the antimicrobial resistance frequencies of the isolates obtained during the period 2006-2012 for 22 antibiotics, and the molecular characterization of multidrug-resistant strains isolated from endemic cases of shigellosis in the remote islands of India, with special reference to fluoroquinolone and third-generation cephalosporins resistance. During the period from January 2006 to December 2011, stool samples were obtained and processed to isolate Shigella spp. The isolates were evaluated with respect to their antibiotic resistance pattern and various multidrug resistance determinants, including resistance genes, quinolone resistance determinants, and extended-spectrum β-lactamase (ESBL) production. Morbidity for shigellosis was found to be 9.3 % among children in these islands. Cases of shigellosis occurred mainly during the rainy seasons and were found to be higher in the age group 2-5 years. A wide spectrum of resistance was observed among the Shigella strains, and more than 50 % of the isolates were multidrug-resistant. The development of multidrug-resistant strains was found to be associated with various drug-resistant genes, multiple mutations in the quinolone resistance-determining region (QRDR), and the presence of plasmid-mediated quinolone-resistant determinants and efflux pump mediators. This report represents the first presentation of the results of long-term surveillance and molecular characterization concerning antimicrobial resistances in clinical Shigella strains in these islands. Information gathered as part of the investigations will be instrumental in identifying emerging antimicrobial resistance, for developing treatment guidelines appropriate for that community, and to provide baseline data with which to compare outbreak strains in the future.

Cost Attributable to Nosocomial Bacteremia. Analysis According to Microorganism and Antimicrobial Sensitivity in a University Hospital in Barcelona.

PubMed

Riu, Marta; Chiarello, Pietro; Terradas, Roser; Sala, Maria; Garcia-Alzorriz, Enric; Castells, Xavier; Grau, Santiago; Cots, Francesc

2016-01-01

To calculate the incremental cost of nosocomial bacteremia caused by the most common organisms, classified by their antimicrobial susceptibility. We selected patients who developed nosocomial bacteremia caused by Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, or Pseudomonas aeruginosa. These microorganisms were analyzed because of their high prevalence and they frequently present multidrug resistance. A control group consisted of patients classified within the same all-patient refined-diagnosis related group without bacteremia. Our hospital has an established cost accounting system (full-costing) that uses activity-based criteria to analyze cost distribution. A logistic regression model was fitted to estimate the probability of developing bacteremia for each admission (propensity score) and was used for propensity score matching adjustment. Subsequently, the propensity score was included in an econometric model to adjust the incremental cost of patients who developed bacteremia, as well as differences in this cost, depending on whether the microorganism was multidrug-resistant or multidrug-sensitive. A total of 571 admissions with bacteremia matched the inclusion criteria and 82,022 were included in the control group. The mean cost was € 25,891 for admissions with bacteremia and € 6,750 for those without bacteremia. The mean incremental cost was estimated at € 15,151 (CI, € 11,570 to € 18,733). Multidrug-resistant P. aeruginosa bacteremia had the highest mean incremental cost, € 44,709 (CI, € 34,559 to € 54,859). Antimicrobial-susceptible E. coli nosocomial bacteremia had the lowest mean incremental cost, € 10,481 (CI, € 8,752 to € 12,210). Despite their lower cost, episodes of antimicrobial-susceptible E. coli nosocomial bacteremia had a major impact due to their high frequency. Adjustment of hospital cost according to the organism causing bacteremia and antibiotic sensitivity could improve prevention strategies and allow their prioritization according to their overall impact and costs. Infection reduction is a strategy to reduce resistance.

Occurrence of porphyromonas gingivalis and its antibacterial susceptibility to metronidazole and tetracycline in patients with chronic periodontitis.

PubMed

Gamboa, Fredy; Acosta, Adriana; García, Dabeiba-Adriana; Velosa, Juliana; Araya, Natalia; Ledergerber, Roberto

2014-01-01

Chronic periodontitis is a multifactorial infectious disease associated with Gram-negative strict anaerobes which are immersed in the subgingival biofilm. Porphyromonas gingivalis, an important periodontal pathogen, is frequently detected in patients with chronic periodontitis. Although isolates of P. gingivalis tend to be susceptible to most antimicrobial agents, relatively little information is available on its in vitro antimicrobial susceptibility. The aim of this study was to determine the frequency of P. gingivalis in patients with chronic periodontitis and to assess antimicrobial susceptibility in terms of minimum inhibitory concentration (MIC) of clinical isolates to metronidazole and tetracycline. A descriptive, observational study was performed including 87 patients with chronic periodontitis. Samples were taken from the periodontal pocket using paper points, which were placed in thioglycollate broth. Samples were incubated for 4 hours at 37°C in anaerobic conditions and finally replated on Wilkins-Chalgren anaerobic agar (Oxoid). Bacteria were identified using the RapIDTMANAII system (Remel) and antimicrobial susceptibility was determined with the M.I.C. Evaluator test (MICE, Oxoid). P. gingivalis was identified in 30 of the 87 patients with chronic periodontitis, which represents a frequency of 34.5%. All 30 isolates (100%) were sensitive to metronidazole, with MIC values ranging from 0015-4ug/ml. Regarding tetracycline, 27 isolates (90%) were sensitive, with MIC values ranging from <0.015 to 4 ug /ml, the remaining three isolates (10%) were resistant to tetracycline with MIC values of 8ug/ ml. There was no statistically significant difference in age, gender, pocket depth, clinical attachment level and severity of periodontitis between the group of patients with chronic periodontitis and P. gingivalis and the group of patients with chronic periodontitis without P. gingivalis. In conclusion, P. gingivalis was found at a frequency of 34.5% in patients with chronic periodontitis and clinical isolates were highly sensitive to metronidazole and tetracycline.

Cost Attributable to Nosocomial Bacteremia. Analysis According to Microorganism and Antimicrobial Sensitivity in a University Hospital in Barcelona

PubMed Central

Riu, Marta; Chiarello, Pietro; Terradas, Roser; Sala, Maria; Garcia-Alzorriz, Enric; Castells, Xavier; Grau, Santiago; Cots, Francesc

2016-01-01

Aim To calculate the incremental cost of nosocomial bacteremia caused by the most common organisms, classified by their antimicrobial susceptibility. Methods We selected patients who developed nosocomial bacteremia caused by Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, or Pseudomonas aeruginosa. These microorganisms were analyzed because of their high prevalence and they frequently present multidrug resistance. A control group consisted of patients classified within the same all-patient refined-diagnosis related group without bacteremia. Our hospital has an established cost accounting system (full-costing) that uses activity-based criteria to analyze cost distribution. A logistic regression model was fitted to estimate the probability of developing bacteremia for each admission (propensity score) and was used for propensity score matching adjustment. Subsequently, the propensity score was included in an econometric model to adjust the incremental cost of patients who developed bacteremia, as well as differences in this cost, depending on whether the microorganism was multidrug-resistant or multidrug-sensitive. Results A total of 571 admissions with bacteremia matched the inclusion criteria and 82,022 were included in the control group. The mean cost was € 25,891 for admissions with bacteremia and € 6,750 for those without bacteremia. The mean incremental cost was estimated at € 15,151 (CI, € 11,570 to € 18,733). Multidrug-resistant P. aeruginosa bacteremia had the highest mean incremental cost, € 44,709 (CI, € 34,559 to € 54,859). Antimicrobial-susceptible E. coli nosocomial bacteremia had the lowest mean incremental cost, € 10,481 (CI, € 8,752 to € 12,210). Despite their lower cost, episodes of antimicrobial-susceptible E. coli nosocomial bacteremia had a major impact due to their high frequency. Conclusions Adjustment of hospital cost according to the organism causing bacteremia and antibiotic sensitivity could improve prevention strategies and allow their prioritization according to their overall impact and costs. Infection reduction is a strategy to reduce resistance. PMID:27055117

Antibacterial activity of selected standard strains of lactic acid bacteria producing bacteriocins--pilot study.

PubMed

Bodaszewska-Lubas, Malgorzata; Brzychczy-Wloch, Monika; Gosiewski, Tomasz; Heczko, Piotr B

2012-10-25

In this paper, an attempt was made to evaluate the antibacterial potential of standard strains of lactic acid bacteria (LAB) producing bacteriocins of various classes, thus demonstrating various mechanisms of cell membrane damages against the Streptococcus agalactiae strains (Group B Streptococcus, GBS), depending on surface polysaccharides and surface alpha-like protein genes. Antimicrobial property of the strains of L. plantarum C 11, L. sakei DSMZ 6333, and L. lactis ATCC 11454 producing bacteriocins: JK and EF plantaricins, sakacin and nisin, respectively, against the GBS strains was evaluated. The chosen to the study GBS strains were represented by serotypes Ia, Ib, II, III, V and they had bca, epsilon, rib, alp2 or alp3 alpha-like protein genes. The experiment was conducted by means of suspension culture and the bacteria count was determined using the serial dilution method. A great ability of L. plantarum C 11 strain was proven to inhibit the GBS growth. The strain of L. sakei DSMZ 6333 did not demonstrate any ability to inhibit the growth of GBS, whereas L. lactis ATCC 11454 inhibited the growth of S. agalactiae indicator strains to a minor extent. Statistically significant differences were demonstrated between the GBS strains representing various serotypes against the antimicrobial activity of model LAB strains. The least sensitive to the activity of bacteriocins were the strains representing serotypes Ib and III, whereas the strains representing serotype II were the most sensitive. The sensitivity of the GBS strains to the antimicrobial activity of LAB was not dependent on alpha-like protein genes. Among the LAB standard strains producing bacteriocins, the strongest antimicrobial property was observed in the strain of L. plantarum C 11. Because of the generally known and verified strong antagonistic property of the strains of L. plantarum species against indicator bacteria, it is necessary to further pursue the research presented in this paper.

Open standing castration in Thoroughbred racehorses in Hong Kong: Prevalence and severity of complications 30 days post-castration.

PubMed

Rosanowski, S M; MacEoin, F; Graham, R J T Y; Riggs, C M

2018-05-01

Complications following open standing castration (OSC) in Thoroughbred racehorses are well recognised but variation in their prevalence and severity between populations is not well documented. To describe the prevalence and severity of complications in the 30 days following OSC. A retrospective cohort study of veterinary clinical records relating to horses that underwent OSC between July 2007 and July 2012. Complications were graded on a severity score from N, no complications, to C3, severe complications. Additional data were accessed for each horse including age, import date, racing history, trainer and veterinarian performing the castration. Bacterial culture and antimicrobial sensitivities were performed on a limited number of castration wounds that became infected. In total, 250 horses were castrated in Hong Kong using the OSC technique over the period of the study. Sixty percent (150/250) of horses experienced some type of post-castration complication, with eight horses experiencing a severe (C3) complication requiring intensive veterinary treatment. Scrotal swelling, funiculitis and seroma formation were present in 70.0%, 36.7% and 24.7% of cases respectively. Most horses experiencing complications required wound reopening (87.3%; 131/150), and/or an extended course of first-line antimicrobials and/or nonsteroidal anti-inflammatory drugs (75/150; 50.0%). Eight horses had cultures submitted for bacterial sensitivity, with 17 bacterial isolates grown. In vitro, the bacteria cultured were sensitive to enrofloxacin (76%; 13/17) and ceftiofur (100%; 17/17). Resistance was detected to penicillin, gentamicin, oxytetracycline, metronidazole and trimethoprim-sulfadiazine. Differences in post-castration management cannot be accounted for in this study. Complications following OSC in horses in Hong Kong were common. The majority were mild and were successfully treated using antimicrobials and simple wound management. Given the high rate of complications and antimicrobial usage identified in this study, a review of the technique is warranted. © 2017 EVJ Ltd.

Elaboration of a global strategy for containing microbial drug resistance.

PubMed

Zabicki, W

2001-01-01

The World Health Organization is engaged in developing the Global Strategy for Containment of Antimicrobial Resistance. The preliminary document WHO/CDC/CSR/DRS/2000.I Draft has already been distributed, and remarks have been solicited.
The World Health Assembly Resolution of 1998 urged Member States to encourage the appropriate and cost-effective use of antimicrobials. Member States were requested to implement effective systems of microbial resistance surveillance and to monitor volumes and patterns of antimicrobial drug use.
The phenomenon of antimicrobial resistance is rising rapidly and causing growing international concern. Many countries have undertaken their own national plans to address the problem.
The overall aim of the strategy being developed is to find the most effective forms and to prevent the spread of antimicrobial resistance and resistant microbes. The strategy covers the following topics: patients and general community, prescribers, hospitals, veterinarians, manufacturers and drug dispensers, and international aspects.
The strategy is being developed on the basis of expert opinions, published reports, reviews of specific topics specially commissioned by various international and national bodies, and a large body of literature with a list of publications containing over 100 items.

Microbiology of Urinary Tract Infections in Gaborone, Botswana

PubMed Central

Renuart, Andrew J.; Goldfarb, David M.; Mokomane, Margaret; Tawanana, Ephraim O.; Narasimhamurthy, Mohan; Steenhoff, Andrew P.; Silverman, Jonathan A.

2013-01-01

Objective The microbiology and epidemiology of UTI pathogens are largely unknown in Botswana, a high prevalence HIV setting. Using laboratory data from the largest referral hospital and a private hospital, we describe the major pathogens causing UTI and their antimicrobial resistance patterns. Methods This retrospective study examined antimicrobial susceptibility data for urine samples collected at Princess Marina Hospital (PMH), Bokamoso Private Hospital (BPH), or one of their affiliated outpatient clinics. A urine sample was included in our dataset if it demonstrated pure growth of a single organism and accompanying antimicrobial susceptibility and subject demographic data were available. Results A total of 744 samples were included. Greater than 10% resistance was observed for amoxicillin, co-trimoxazole, amoxicillin-clavulanate, and ciprofloxacin. Resistance of E. coli isolates to ampicillin and co-trimoxazole was greater than 60% in all settings. HIV status did not significantly impact the microbiology of UTIs, but did impact antimicrobial resistance to co-trimoxazole. Conclusions Data suggests that antimicrobial resistance has already emerged to most oral antibiotics, making empiric management of outpatient UTIs challenging. Ampicillin, co-trimoxazole, and ciprofloxacin should not be used as empiric treatment for UTI in this context. Nitrofurantoin could be used for simple cystitis; aminoglycosides for uncomplicated UTI in inpatients. PMID:23469239

Microbiology of urinary tract infections in Gaborone, Botswana.

PubMed

Renuart, Andrew J; Goldfarb, David M; Mokomane, Margaret; Tawanana, Ephraim O; Narasimhamurthy, Mohan; Steenhoff, Andrew P; Silverman, Jonathan A

2013-01-01

The microbiology and epidemiology of UTI pathogens are largely unknown in Botswana, a high prevalence HIV setting. Using laboratory data from the largest referral hospital and a private hospital, we describe the major pathogens causing UTI and their antimicrobial resistance patterns. This retrospective study examined antimicrobial susceptibility data for urine samples collected at Princess Marina Hospital (PMH), Bokamoso Private Hospital (BPH), or one of their affiliated outpatient clinics. A urine sample was included in our dataset if it demonstrated pure growth of a single organism and accompanying antimicrobial susceptibility and subject demographic data were available. A total of 744 samples were included. Greater than 10% resistance was observed for amoxicillin, co-trimoxazole, amoxicillin-clavulanate, and ciprofloxacin. Resistance of E. coli isolates to ampicillin and co-trimoxazole was greater than 60% in all settings. HIV status did not significantly impact the microbiology of UTIs, but did impact antimicrobial resistance to co-trimoxazole. Data suggests that antimicrobial resistance has already emerged to most oral antibiotics, making empiric management of outpatient UTIs challenging. Ampicillin, co-trimoxazole, and ciprofloxacin should not be used as empiric treatment for UTI in this context. Nitrofurantoin could be used for simple cystitis; aminoglycosides for uncomplicated UTI in inpatients.

Antimicrobial resistance among Escherichia coli that cause childhood community-acquired urinary tract infections in Northern Italy

PubMed Central

2011-01-01

Abstracts Background Resistance rate of Escherichia coli against antimicrobials that are commonly prescribed in pediatric urinary tract infections is currently a matter of concern. Methods The antimicrobial susceptibility patterns of uropathogenic Escherichia coli strains to the common antibimcrobials ampicillin, cotrimoxazole, coamoxyclav, ceftazidime, ceftriaxone, nitrofurantoin, and gentamycin were determined in 177 children aged from 2 to 36 months. They presented with their first symptomatic community acquired urinary tract infection at the Department of Pediatrics, San Leopoldo Mandic Hospital, Merate-Lecco. Results High rates of ampicillin (inpatients: 50%; outpatients: 52%) resistance were identified. The resistance for cotrimoxazole (inpatients: 22%; outpatients: 15%) and especially coamoxyclav (inpatients: 6%; outpatients: 10%) was less pronounced than that to ampicillin. No resistance or less than 1% of resistance was identified for ceftazidime, ceftriaxone, nitrofurantoin, and gentamycin both in inpatients and in outpatients. Conclusions Italian children affected with a community acquired urinary tract infection are initially managed orally with coamoxyclav or parenterally with ceftriaxone. The results of the present retrospective analysis support this attitude. Parenteral ceftriaxone or an aminoglycoside should be considered for patients on antimicrobial prophylaxis or recently prescribed antimicrobials. PMID:21211026

Antimicrobial susceptibility of Salmonella enterica isolates from healthy breeder and broiler flocks in Portugal.

PubMed

Clemente, Lurdes; Correia, Ivone; Themudo, Patrícia; Neto, Isabel; Caniça, Manuela; Bernardo, Fernando

2014-05-01

Three hundred and thirty-three isolates representing 40 different serotypes of Salmonella enterica, recovered from environmental and faecal samples of breeder and broiler flocks from 2009 to 2011, were studied. Antimicrobial susceptibility was determined by measuring the minimal inhibitory concentration of 11 antimicrobials using the agar dilution method. Salmonella Havana, S. Enteritidis and S. Mbandaka were the most common serotypes isolated from broiler flocks, while S. Enteritidis was the common isolate from breeder flocks. The frequency of non-wild-type Salmonella isolates (those with decreased susceptibility to the different antimicrobials) varied according to serotype. S. Mbandaka in broilers and S. Enteritidis in both breeders and broilers showed higher frequencies of reduced susceptibility to quinolones, but clinical resistance towards ciprofloxacin was not observed. Reduced susceptibility to sulfamethoxazole, tetracycline, ampicillin and streptomycin were common in Salmonella Typhimurium isolates. Two isolates of S. Havana from broilers were resistant to cefotaxime and phenotypically categorised as extended-spectrum β-lactamase producers. The results presented in this study provide useful data on the antimicrobial susceptibility of different Salmonella serotypes and highlight the high diversity of multi-drug resistance patterns present. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antimicrobial resistance trends among Salmonella isolates obtained from dairy cattle in the northeastern United States, 2004-2011.

PubMed

Cummings, Kevin J; Perkins, Gillian A; Khatibzadeh, Sarah M; Warnick, Lorin D; Altier, Craig

2013-04-01

Monitoring antimicrobial resistance trends among bacteria isolated from food animals and people is necessary to inform public policy regarding appropriate antimicrobial use. Our objectives were to describe the antimicrobial resistance status of Salmonella isolates from dairy cattle in the northeastern United States and to identify trends in resistance to various antimicrobial agents over time. Data were collected retrospectively for all bovine Salmonella isolates that were obtained from samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. Temporal trends in the prevalence of resistant Salmonella were investigated for each antimicrobial agent using the Cochran-Armitage trend test. Antimicrobial susceptibility testing was performed on 2745 bovine Salmonella isolates from clinical samples submitted during the study period. Overall resistance to each antimicrobial agent ranged from 0% (amikacin, ciprofloxacin, and nalidixic acid) to 72.0% (sulfadimethoxine). There was evidence of a significantly decreasing trend in prevalence of resistance to most agents: amoxicillin/clavulanic acid (AUG), ampicillin (AMP), cefoxitin (FOX), ceftiofur (TIO), ceftriaxone (AXO), chloramphenicol (CHL), chlortetracycline (CTET), florfenicol (FFN), kanamycin (KAN), neomycin (NEO), oxytetracycline (OXY), spectinomycin (SPE), streptomycin (STR), sulfadimethoxine (SDM), sulfisoxazole (FIS), and tetracycline (TET). Among the 265 isolates that were tested using the National Antimicrobial Resistance Monitoring System (NARMS) panel, the most common resistance patterns were pansusceptible (54.0%), AUG-AMP-FOX-TIO-AXO-CHL-KAN-STR-FIS-TET (18.1%), and AUG-AMP-FOX-TIO-AXO-CHL-STR-FIS-TET (12.1%). Increasing prevalence of S. enterica serovar Cerro over the course of the study period presumably had an impact on the observed resistance trends. Nevertheless, these results do not support the notion that the current level of antimicrobial use in dairy cattle is driving an increase in the emergence and dissemination of drug-resistant Salmonella in the region served by the laboratory.

Prevalence of virulence and antimicrobial resistance genes in Salmonella spp. isolated from commercial chickens and human clinical isolates from South Africa and Brazil.

PubMed

Zishiri, Oliver T; Mkhize, Nelisiwe; Mukaratirwa, Samson

2016-05-26

Salmonellosis is a significant public health concern around the world. The injudicious use of antimicrobial agents in poultry production for treatment, growth promotion and prophylaxis has resulted in the emergence of drug resistant strains of Salmonella. The current study was conducted to investigate the prevalence of virulence and antimicrobial resistance genes from Salmonella isolated from South African and Brazilian broiler chickens as well as human clinical isolates. Out of a total of 200 chicken samples that were collected from South Africa 102 (51%) tested positive for Salmonella using the InvA gene. Of the overall 146 Salmonella positive samples that were screened for the iroB gene most of them were confirmed to be Salmonella enterica with the following prevalence rates: 85% of human clinical samples, 68.6% of South African chicken isolates and 70.8% of Brazilian chicken samples. All Salmonella isolates obtained were subjected to antimicrobial susceptibility testing with 10 antibiotics. Salmonella isolates from South African chickens exhibited resistance to almost all antimicrobial agents used, such as tetracycline (93%), trimethoprim-sulfamthoxazole (84%), trimethoprim (78.4%), kanamycin (74%), gentamicin (48%), ampicillin (47%), amoxicillin (31%), chloramphenicol (31%), erythromycin (18%) and streptomycin (12%). All samples were further subjected to PCR in order to screen some common antimicrobial and virulence genes of interest namely spiC, pipD, misL, orfL, pse-1, tet A, tet B, ant (3")-la, sul 1 and sul. All Salmonella positive isolates exhibited resistance to at least one antimicrobial agent; however, antimicrobial resistance patterns demonstrated that multiple drug resistance was prevalent. The findings provide evidence that broiler chickens are colonised by pathogenic Salmonella harbouring antimicrobial resistance genes. Therefore, it is evident that there is a need for prudent use of antimicrobial agents in poultry production systems in order to mitigate the proliferation of multiple drug resistance across species.

Prevalence of virulence and antimicrobial resistance genes in Salmonella spp. isolated from commercial chickens and human clinical isolates from South Africa and Brazil.

PubMed

Zishiri, Oliver T; Mkhize, Nelisiwe; Mukaratirwa, Samson

2016-05-26

Salmonellosis is a significant public health concern around the world. The injudicious use of antimicrobial agents in poultry production for treatment, growth promotion and prophylaxis has resulted in the emergence of drug resistant strains of Salmonella. The current study was conducted to investigate the prevalence of virulence and antimicrobial resistance genes from Salmonella isolated from South African and Brazilian broiler chickens as well as human clinical isolates. Out of a total of 200 chicken samples that were collected from South Africa 102 (51%) tested positive for Salmonella using the InvA gene. Of the overall 146 Salmonella positive samples that were screened for the iroB gene most of them were confirmed to be Salmonella enterica with the following prevalence rates: 85% of human clinical samples, 68.6% of South African chicken isolates and 70.8% of Brazilian chicken samples. All Salmonella isolates obtained were subjected to antimicrobial susceptibility testing with 10 antibiotics. Salmonella isolates from South African chickens exhibited resistance to almost all antimicrobial agents used, such as tetracycline (93%), trimethoprim-sulfamthoxazole (84%), trimethoprim (78.4%), kanamycin (74%), gentamicin (48%), ampicillin (47%), amoxicillin (31%), chloramphenicol (31%), erythromycin (18%) and streptomycin (12%). All samples were further subjected to PCR in order to screen some common antimicrobial and virulence genes of interest namely spiC, pipD, misL, orfL, pse-1, tet A, tet B, ant (3")-la, sul 1 and sul. All Salmonella positive isolates exhibited resistance to at least one antimicrobial agent; however, antimicrobial resistance patterns demonstrated that multiple drug resistance was prevalent. The findings provide evidence that broiler chickens are colonised by pathogenic Salmonella harbouring antimicrobial resistance genes. Therefore, it is evident that there is a need for prudent use of antimicrobial agents in poultry production systems in order to mitigate the proliferation of multiple drug resistance across species.

Antimicrobial misuse in pediatric urinary tract infections: recurrences and renal scarring.

PubMed

Jayaweera, Jayaweera Arachchige Asela Sampath; Reyes, Mohommed

2018-06-25

In children, urinary tract infection (UTI) is one of a common bacterial infection. This study was conducted to detect the uropathogen, antimicrobial susceptibility, pathogen associated with recurrences and renal scarring in children initially taken care from general practitioners and later presented to tertiary care. Every inward UTI episode, culture and antimicrobial susceptibility was done while on past 6-month, history of infections and use of antimicrobials was collected using clinical records and demonstration of antimicrobials. Children with recurrent pyelonephritis was followed and in vitro bio film formation was assessed. Frequency of UTI was significantly high among infants (p = 0.03). Last 6-month, all (220) were exposed to antimicrobials. Cefixime was the commonly prescribed antimicrobial (p = 0.02). In current UTI episode, 64.5% (142/220) of children with UTI were consulted GPs' prior to seek treatment from tertiary care pediatric unit (p = 0.02). While on follow up child who developed UTI, found urine culture isolates were significantly shifted from E. coli and K. pneumoniae to extended spectrum of beta-lactamase (ESBL) E. coli and K. pneumoniae. Out of 208 participants, 36 of them had re-current pyelonephritis (R-PN). Renal scarring (RS) was detected in 22 out of 70 patients with pyelonephritis following dimercaptosuccinic acid scan. Following each episodes of recurrent pyelonephritis 11% of new scar formation was detected (p = 0.02). Bio film forming E. coli and K. pneumoniae was significantly associated in patients with R-PN (p = 0.04). Medical care providers often prescribe antimicrobials without having an etiological diagnosis. While continuing exposure of third generation cephalosporin and carbapenem leads to development of ESBL and CRE microbes in great. The empiric uses of antimicrobials need to be stream lined with local epidemiology and antimicrobial susceptibility pattern. R-PN in childhood leads to RS. In great, bio film formation act as the focus for such recurrences.

Antimicrobial consumption at Auckland City Hospital: 2006-2009.

PubMed

Ticehurst, Rob; Thomast, Mark

2011-04-15

We aimed to determine the level of antimicrobial consumption by adult inpatients at Auckland City Hospital (Auckland, New Zealand) and to compare our findings with those in other developed nations. We used the computerised records of the central Auckland District Health Board (ADHB) pharmacy to measure the amount of antimicrobials dispensed to inpatients (excluding psychiatric units, day stay units and outpatient clinics) during 2006 to 2009. The total weight of each antimicrobial dispensed was used to determine the number of defined daily doses (DDDs) dispensed. The Information Management and Technical Services department of ADHB provided data on the number of admissions and inpatient days, and these data, together with information from the 2006 census, were used to calculate antimicrobial consumption for adult inpatients measured in DDDs/100 admissions, DDDs/100 inpatient days and DDDs/1000 population. Total antimicrobial consumption by adult inpatients increased from 74 DDDs/100 inpatient days in 2006 to 80.3 DDDs/100 inpatient days in 2009. The level of consumption did not vary greatly with the season. The total level of consumption was very similar to that seen in adult inpatients in hospitals in Australia and Scandinavian countries. The level of consumption of fluoroquinolones, third or fourth generation cephalosporins, carbapenems and vancomycin (antimicrobial classes that are not available for unrestricted use in Auckland City Hospital) was comparable to or less than that seen in adult inpatients in hospitals in Australia or Scandinavian countries. Beta-lactamase susceptible penicillins (such as benzyl penicillin and phenoxymethylpenicillin) comprised a relatively small proportion of total penicillin use and beta-lactamase inhibitor combinations (predominantly amoxicillin/clavulanate) a relatively large proportion of total penicillin use, when compared with Scandinavian hospitals. The antimicrobial stewardship programme at Auckland City Hospital has resulted in a generally prudent level of consumption in recent years. Opportunities exist to improve the pattern of antimicrobial prescribing in the expectation that this will help to slow the spread of antimicrobial resistance in our community.

Lipid composition and sensitivity of Prototheca wickerhamii to membrane-active antimicrobial agents.

PubMed Central

Sud, I J; Feingold, D S

1979-01-01

The lipid composition of Prototheca wickerhamii ATCC 16529 is presented and discussed in relation to the unique susceptibility of the organism to drugs of three membrane-active antimicrobial classes: the polyenes, the polymyxins, and the imidazoles. The presence of ergosterol in the neutral lipid fraction of the membrane is likely responsible for the exquisite susceptibility to amphotericin B. The presence of a large quantity of free fatty acids in the membrane appears responsible for imidazole susceptibility. The membrane determinants of polymyxin B susceptibility are less well defined. PMID:518077

Identification of Group G Streptococcal Isolates from Companion Animals in Japan and Their Antimicrobial Resistance Patterns.

PubMed

Tsuyuki, Yuzo; Kurita, Goro; Murata, Yoshiteru; Goto, Mieko; Takahashi, Takashi

2017-07-24

In this study, we conducted a species-level identification of group G streptococcal (GGS) isolates from companion animals in Japan and analyzed antimicrobial resistance (AMR) patterns. Strains were isolated from sterile and non-sterile specimens collected from 72 animals with clinical signs or symptoms in April-May, 2015. We identified the strain by 16S rRNA sequencing, mass spectrometry (MS), and an automated method based on their biochemical properties. Antimicrobial susceptibility was determined using the broth microdilution method and E-test. AMR determinants (erm(A), erm(B), mef(A), tet(M), tet(O), tet(K), tet(L), and tet(S)) in corresponding resistant isolates were amplified by PCR. The 16S rRNA sequencing identified the GGS species as Streptococcus canis (n = 68), Streptococcus dysgalactiae subsp. equisimilis (n = 3), and S. dysgalactiae subsp. dysgalactiae (n = 1). However, there were discrepancies between the sequencing data and both the MS and automated identification data. MS and the automated biochemical technique identified 18 and 37 of the 68 sequencing-identified S. canis strains, respectively. The AMR rates were 20.8% for tetracycline and 5.6% for clarithromycin, with minimum inhibitory concentrations (MIC) 50 -MIC 90 of 2-64 and ≤ 0.12-0.25μg/mL, respectively. AMR genotyping showed single or combined genotypes: erm(B) or tet(M)-tet(O)-tet(S). Our findings show the unique characteristics of GGS isolates from companion animals in Japan in terms of species-level identification and AMR patterns.

Molecular and antimicrobial susceptibility profiling of Streptococcus dysgalactiae isolated from swine.

PubMed

Moreno, Luisa Z; da Costa, Barbara L P; Matajira, Carlos E C; Gomes, Vasco T M; Mesquita, Renan E; Silva, Ana Paula S; Moreno, Andrea M

2016-10-01

Streptococcus dysgalactiae subspecies equisimilis and dysgalactiae were isolated from swine clinical specimens. The subspecies equisimilis presented 2 clonal patterns with 85% genetic similarity, whereas subspecies dysgalactiae presented distinct band pattern with less than 80% similarity with equisimilis genotypes. Isolates presented high MIC values to tetracyclines, danofloxacin, spectinomycin, tiamulin, and clindamycin. Copyright © 2016 Elsevier Inc. All rights reserved.

Antimicrobials for the treatment of urinary tract infection in pregnancy: practices in southern India.

PubMed

Mathai, Elizabeth; Thomas, Raja John; Chandy, Sujith; Mathai, Matthews; Bergstrom, Staffan

2004-09-01

Although urinary tract infection (UTI) in pregnancy is a common medical problem, very little is known about the susceptibility patterns of bacteria causing UTI and the prescription practices for UTI in pregnancy in low-income countries. Studies were, therefore, carried out in southern India to document the susceptibility patterns and to compare these with prescription practices. Data on susceptibility patterns of bacteria isolated in significant counts from urine of pregnant women suspected to have urinary infection were collected. Prescribing patterns for these infections were ascertained using a questionnaire. About 90% of E. coli causing UTI is still susceptible to nitrofurantoin, a relatively inexpensive and safe drug. However, less than 25% of doctors used it for treatment of cystitis. Cephalosporins were most commonly used in hospital practice for the treatment of UTI. Amoxycillin was being used widely to treat UTI in pregnancy in spite of high prevalence of resistance. There were wide variations in the duration of therapy and use of prophylaxis. Our findings indicate an urgent need for proper guidelines, dissemination of information to practitioners and supervision of antimicrobial usage in low income countries like India. Irrational and unnecessary drug use can be expensive and harmful.

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.

Occurrence and antimicrobial drug susceptibility patterns of commensal and diarrheagenic Escherichia coli in fecal microbiota from children with and without acute diarrhea.

PubMed

Garcia, Patrícia G; Silva, Vânia L; Diniz, Cláudio G

2011-02-01

Acute diarrhea is a public health problem and an important cause of morbidity and mortality, especially in developing countries. The etiology is varied, and the diarrheagenic Escherichia coli pathotypes are among the most important. Our objectives were to determine the occurrence of commensal and diarrheagenic E. coli strains in fecal samples from children under five years old and their drug susceptibility patterns. E. coli were isolated from 141 fresh fecal samples; 84 were obtained from clinically injured donors with acute diarrhea (AD) and 57 from clinically healthy donors without diarrhea (WD). Presumptive phenotypic species identification was carried out and confirmed by amplification of specific 16S ribosomal RNA encoding DNA. Multiplex PCR was performed to characterize the diarrheagenic E. coli strains. Drug susceptibility patterns were determined by the disc-diffusion method. In total, 220 strains were recovered from the fecal specimens (61.8% from AD and 38.2% from WD). Diarrheagenic E. coli was identified at a rate of 36.8% (n=50) in diarrheic feces and 29.8% (n=25) in non-diarrheic feces. Enteroaggregative E. coli was the most frequently identified pathotype in the AD group (16.2%) and the only pathotype identified in the WD group (30.9%). Enteropathogenic E. coli was the second most isolated pathotype (10.3%), followed by Shiga toxin-producing E. coli (7.4%) and enterotoxigenic E. coli (2.9%). No enteroinvasive E. coli strains were recovered. The isolates showed high resistance rates against ampicillin, tetracycline, and sulfamethoxazole-trimethoprim. The most effective drugs were ceftazidime, ceftriaxone, imipenem and piperacillin-tazobactam, for which no resistance was observed. Differentiation between the diarrheagenic E. coli pathotypes is of great importance since they are involved in acute diarrheal diseases and may require specific antimicrobial chemotherapy. The high antimicrobial resistance observed in our study raises a broad discussion on the indiscriminate or improper use of antimicrobials, besides the risks of self-medication.

Urinary tract infections caused by Pseudomonas aeruginosa among children in Southern Poland: Virulence factors and antibiotic resistance.

PubMed

Pobiega, M; Maciag, J; Pomorska-Wesolowska, M; Chmielarczyk, A; Romaniszyn, D; Ziolkowski, G; Heczko, P B; Wojkowska-Mach, J; Bulanda, M

2016-02-01

The aim of this study was to analyze antibiotic resistance and virulence patterns in Pseudomonas aeruginosa (PAR) isolates from urinary tract infections among children in Southern Poland. This study comprised consecutive, non-repetitive PAR isolates sent from two collaborative laboratories. The study group consisted of children aged up to 17 years from Southern Poland with culture-proven PAR UTIs. Relevant information about patients with UTIs, such as age, sex, and type of infection (polymicrobial or monomicrobial), was collected. Isolates were screened for major virulence factors found in uropathogenic PAR strains. Multidrug-resistant (MDR) strains were defined as strains not susceptible to one antimicrobial in at least three different antimicrobial classes. Extensively drug resistant (XDR) strains were defined as strains susceptible to no more than two antimicrobial classes. The total prevalence of PAR UTIs was 2.1%, and in children <5 years of age it was 3.0%. A total of 26 isolates was tested: 21 from outpatients and five from inpatients. Most infections (80.8%) occurred in children ≤ 4 years of age. The most prevalent virulence gene was exoY (96.2%). The prevalence of other effector proteins was 88.5% for exoT, 92.3% for exoS, and 19.2% for exoU. The gene for LasB was present in 80.8% of isolates; the gene for AprA in 61.5%; the gene for PilA in 19.2%; and the gene for PilB was not detected. The PAR isolates were generally susceptible to beta-lactam and aminoglycoside antimicrobials. All isolates were also susceptible to colistin. A large proportion of isolates were resistant to carbapenems and fluoroquinolones (Fig. 1). No significant differences were found in antimicrobial resistance between males and females or inpatients and outpatients (p > 0.05 for all tested antimicrobials), or in antimicrobial resistance between younger (≤ 5 years old, n = 21) and older (> 5 years old, n = 5) children (p > 0.05 for all tested antimicrobials). Two isolates were classified as XDR and none as MDR. The EDTA test yielded one MBL-positive isolate (3.8%), from a 17-year-old patient in home care. No isolates with genes for the KPC, IMP, or VIM were identified. As data on UTIs in children with Pseudomonas etiology are scarce, this paper provides useful information for clinicians and allows for comparison between Poland and other countries. Our findings have important implications for clinicians treating UTIs empirically, because the success of empiric treatment is based on knowledge of pathogen antimicrobial susceptibility patterns. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Analysis of antimicrobial resistance genes in Aeromonas spp. isolated from cultured freshwater animals in China.

PubMed

Deng, Yu-Ting; Wu, Ya-Li; Tan, Al-Ping; Huang, Yu-Ping; Jiang, Lan; Xue, Hui-Juan; Wang, Wei-Li; Luo, Li; Zhao, Fei

2014-08-01

The development of resistance to antimicrobials used in aquatic animals is an increasing concern for aquaculture and public health. To monitor the occurrence of antimicrobial resistance and resistance genes in Aeromonas, a total of 106 isolates were collected from cultured freshwater animals in China from 1995 to 2012. Antimicrobial susceptibilities were determined by the disk diffusion method. The highest resistance percentage occurred with ampicillin, rifampin, streptomycin, and nalidixic acid. Most strains were sensitive to fluoroquinolones, doxycycline, cefotaxime, chloramphenicol, and amikacin. The isolates from turtle samples had the highest levels of resistance to 11 of the 12 tested antimicrobials when compared with those from fish or shrimp. Polymerase chain reaction and DNA sequence results showed that all trimethoprim/sulfamethoxazole-resistant strains contained sul1, and 37.0% were positive for tetA in tetracycline-resistant strains. ant(3″)-Ia was identified in 13 (24.5%) streptomycin-resistant strains. Plasmid-borne quinolone resistance genes were detected in five Aeromonas hydrophila (4.7%), two of which carried qnrS2, while the other three strains harbored aac(6')-Ib-cr. Two cefotaxime-resistant A. hydrophila were positive for bla(TEM-1) and bla(CTX-M-3). To our knowledge, this is the first report characterizing antimicrobial resistance in Aeromonas isolated from cultured freshwater animals in China, and providing resistance information of pathogen in Chinese aquaculture.

In vitro antimicrobial activity of five essential oils on multidrug resistant Gram-negative clinical isolates

PubMed Central

Sakkas, Hercules; Gousia, Panagiota; Economou, Vangelis; Sakkas, Vassilios; Petsios, Stefanos; Papadopoulou, Chrissanthy

2016-01-01

Aim/Background: The emergence of drug-resistant pathogens has drawn attention on medicinal plants for potential antimicrobial properties. The objective of the present study was the investigation of the antimicrobial activity of five plant essential oils on multidrug resistant Gram-negative bacteria. Materials and Methods: Basil, chamomile blue, origanum, thyme, and tea tree oil were tested against clinical isolates of Acinetobacter baumannii (n = 6), Escherichia coli (n = 4), Klebsiella pneumoniae (n = 7), and Pseudomonas aeruginosa (n = 5) using the broth macrodilution method. Results: The tested essential oils produced variable antibacterial effect, while Chamomile blue oil demonstrated no antibacterial activity. Origanum, Thyme, and Basil oils were ineffective on P. aeruginosa isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values ranged from 0.12% to 1.50% (v/v) for tea tree oil, 0.25-4% (v/v) for origanum and thyme oil, 0.50% to >4% for basil oil and >4% for chamomile blue oil. Compared to literature data on reference strains, the reported MIC values were different by 2SD, denoting less successful antimicrobial activity against multidrug resistant isolates. Conclusions: The antimicrobial activities of the essential oils are influenced by the strain origin (wild, reference, drug sensitive, or resistant) and it should be taken into consideration whenever investigating the plants’ potential for developing new antimicrobials. PMID:27366345

Activity of LL-37, CRAMP and antimicrobial peptide-derived compounds E2, E6 and CP26 against Mycobacterium tuberculosis.

PubMed

Rivas-Santiago, Bruno; Rivas Santiago, Cesar E; Castañeda-Delgado, Julio E; León-Contreras, Juan C; Hancock, Robert E W; Hernandez-Pando, Rogelio

2013-02-01

Tuberculosis (TB) is a major worldwide health problem in part due to the lack of development of new treatments and the emergence of new strains such as multidrug-resistant (MDR) and extensively drug-resistant strains that are threatening and impairing the control of this disease. In this study, the efficacy of natural and synthetic cationic antimicrobial (host defence) peptides that have been shown often to possess broad-spectrum antimicrobial activity was tested. The natural antimicrobial peptides human LL-37 and mouse CRAMP as well as synthetic peptides E2, E6 and CP26 were tested for their activity against Mycobacterium tuberculosis both in in vitro and in vivo models. The peptides had moderate antimicrobial activities, with minimum inhibitory concentrations ranging from 2 μg/mL to 10 μg/mL. In a virulent model of M. tuberculosis lung infection, intratracheal therapeutic application of these peptides three times a week at doses of ca. 1mg/kg led to significant 3-10-fold reductions in lung bacilli after 28-30 days of treatment. The treatments worked both against the drug-sensitive H37Rv strain and a MDR strain. These results indicate that antimicrobial peptides might constitute a novel therapy against TB. Copyright © 2012 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Purification and characterization of two new cell-bound bioactive compounds produced by wild Lactococcus lactis strain.

PubMed

Saraiva, Margarete Alice Fontes; Brede, Dag Anders; Nes, Ingolf Figved; Baracat-Pereira, Maria Cristina; de Queiroz, Marisa Vieira; de Moraes, Célia Alencar

2017-07-03

Novel compounds and innovative methods are required considering that antibiotic resistance has reached a crisis point. In the study, two cell-bound antimicrobial compounds produced by Lactococcus lactis ID1.5 were isolated and partially characterized. Following purification by cationic exchange and a solid-phase C18 column, antimicrobial activity was recovered after three runs of RPC using 60% (v/v) and 100% (v/v) of 2-propanol for elution, suggesting that more than one antimicrobial compound were produced by L. lactis ID1.5, which were in this study called compounds AI and AII. The mass spectrum of AI and AII showed major intensity ions at m/z 1070.05 and 955.9 Da, respectively. The compound AI showed a spectrum of antimicrobial activity mainly against L. lactis species, while the organisms most sensitive to compound AII were Bacillus subtilis, Listeria innocua, Streptococcus pneumoniae and Pseudomonas aeruginosa. The antimicrobial activity of both compounds was suppressed by treatment with Tween 80. Nevertheless, both compounds showed high stability to heat and proteases treatments. The isolated compounds, AI and AII, showed distinct properties from other antimicrobial substances already reported as produced by L. lactis, and have a significant inhibitory effect against two clinically important respiratory pathogens. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A Rigidity-Enhanced Antimicrobial Activity: A Case for Linear Cationic α-Helical Peptide HP(2–20) and Its Four Analogues

PubMed Central

Liu, Li; Fang, Ying; Huang, Qingsheng; Wu, Jianhua

2011-01-01

Linear cationic α-helical antimicrobial peptides are referred to as one of the most likely substitutes for common antibiotics, due to their relatively simple structures (≤40 residues) and various antimicrobial activities against a wide range of pathogens. Of those, HP(2–20) was isolated from Helicobacter pylori ribosomal protein. To reveal a mechanical determinant that may mediate the antimicrobial activities, we examined the mechanical properties and structural stabilities of HP(2–20) and its four analogues of same chain length by steered molecular dynamics simulation. The results indicated the following: the resistance of H-bonds to the tensile extension mediated the early extensive stage; with the loss of H-bonds, the tensile force was dispensed to prompt the conformational phase transition; and Young's moduli (N/m2) of the peptides were about 4∼8×109. These mechanical features were sensitive to the variation of the residue compositions. Furthermore, we found that the antimicrobial activity is rigidity-enhanced, that is, a harder peptide has stronger antimicrobial activity. It suggests that the molecular spring constant may be used to seek a new structure-activity relationship for different α-helical peptide groups. This exciting result was reasonably explained by a possible mechanical mechanism that regulates both the membrane pore formation and the peptide insertion. PMID:21283643

Enhanced antimicrobial activity and structural transitions of a nanofibrillated cellulose-nisin bio-composite suspension.

PubMed

Weishaupt, Ramon; Heuberger, Lukas; Siqueira, Gilberto; Gutt, Beatrice; Zimmermann, Tanja; Maniura-Weber, Katharina; Salentinig, Stefan; Faccio, Greta

2018-05-16

The occurrence of resistance to antibiotics has posed a high demand for novel strategies to fight bacterial infections. Antimicrobial peptides (AMPs) are a promising alternative to con-ventional antibiotics. However, their poor solubility in water and sensitivity to degradation has limited their application. Here we report the design of a smart, pH-responsive antimicro-bial nanobiocomposite material based on the AMP nisin and oxidized nanofibrillated cellulose (TONFC). Morphological transformations of the nano-scale structure of nisin functionalized TONFC fibrils were discovered at pH values between pH 5.8 and 8.0 using small angle X-ray scattering (SAXS). Complementary zeta potential measurements indicate that electrostatic-attractions between the negatively charged TONFC surface and the positively charged nisin molecules are responsible for the integration of nisin. Contrary, shifting the pH level or in-creasing the ionic strength reduce the nisin binding capacity of TONFC. Biological evaluation studies using a bioluminescence-based reporter strain of Bacillus subtilis and a clinically rele-vant strain of Staphylococcus aureus indicated a significantly higher antimicrobial activity of the TONFC-nisin biocomposite compared to the pure nisin against both strains under physio-logical pH and ionic strength conditions. The in-depth characterization of this new class of an-timicrobial bio-composite material based on nanocellulose and nisin, may guide the rational design of sustainable antimicrobial materials.

Antimicrobial function of the GAPDH-related antimicrobial peptide in the skin of skipjack tuna, Katsuwonus pelamis.

PubMed

Seo, Jung-Kil; Lee, Min Jeong; Go, Hye-Jin; Kim, Yeon Jun; Park, Nam Gyu

2014-02-01

A 3.4 kDa of antimicrobial peptide was purified from an acidified skin extract of skipjack tuna, Katsuwonus pelamis, by preparative acid-urea-polyacrylamide gel electrophoresis and C18 reversed-phase HPLC. A comparison of the N-terminal amino acid sequence of the purified peptide with that of other known polypeptides revealed high sequence homology with the YFGAP (Yellowfin tuna Glyceraldehyde-3-phosphate dehydrogenase-related Antimicrobial Peptide); thus, this peptide was identified as the skipjack tuna GAPDH-related antimicrobial peptide (SJGAP). SJGAP showed potent antimicrobial activity against Gram-positive bacteria, such as Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, and Streptococcus iniae (minimal effective concentrations [MECs], 1.2-17.0 μg/mL), Gram-negative bacteria, such as Aeromonas hydrophila, Escherichia coli D31, and Vibrio parahaemolyticus (MECs, 3.1-12.0 μg/mL), and against Candida albicans (MEC, 16.0 μg/mL) without significant hemolytic activity. Antimicrobial activity of this peptide is heat-stable but salt-sensitive. According to the secondary structural prediction and the homology modeling, this peptide consists of three secondary structural motifs, including one α-helix and two parallel β-strands, and forms an amphipathic structure. This peptide showed neither membrane permeabilization ability nor killing ability, but did display a small degree of leakage ability. These results suggest that SJGAP acts through a bacteriostatic process rather than bactericidal one. SJGAP is another GAPDH-related antimicrobial peptide isolated from skipjack tuna and likely plays an important role for GAPDH in the innate immune defense of tuna fish. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antimicrobial activity of chemomechanical gingival retraction products.

PubMed

Hsu, Belinda; Lee, Stephanie; Schwass, Donald; Tompkins, Geoffrey

2017-07-01

Application of astringent hemostatic agents is the most widely used technique for gingival retraction, and a variety of products are offered commercially. However, these products may have additional unintended yet clinically beneficial properties. The authors assessed the antimicrobial activities of marketed retraction products against plaque-associated bacteria in both planktonic and biofilm assays, in vitro. The authors assessed hemostatic solutions, gels, pellets, retraction cords, pastes, and their listed active agents against a collection of microorganisms by means of conventional agar diffusion and minimum bacteriostatic and bactericidal concentration determinations. The authors then tested the most active products against monospecies biofilms grown on hydroxyapatite disks. All of the tested retraction products exhibited some antimicrobial activity. The results of the most active products were comparable with those of a marketed mouthwash. The listed retraction-active agents displayed relatively little activity when tested in pure form. At 10% dilution, some products evidenced inhibitory activity against most tested bacteria within 3 minutes of exposure, whereas others displayed variable effects after 10 minutes. The most active agents reduced, but did not completely prevent, the metabolic activity of a monospecies biofilm. Commercial gingival retraction products exhibit antimicrobial effects to various degrees in vitro. Some products display rapid bactericidal activity. The antimicrobial activity is not owing to the retraction-active agents. Biofilm bacteria are less sensitive to the antimicrobial effects of the agents. The rapidity of killing by some hemostatic agents suggests an antimicrobial effect that may be efficacious during clinical placement. The results of this in vitro study suggest that clinicians should be aware of the potential antimicrobial effects of some hemostatic agents, but more research is needed to confirm these observations in clinical use. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.

The efficacy of the direct clinical intervention for infectious diseases by a pediatric infectious disease specialist in the pediatric ward of a tertiary medical facility without a pediatric antimicrobial stewardship program.

PubMed

Hoshina, T; Yamamoto, N; Ogawa, M; Nakamoto, T; Kusuhara, K

2017-08-01

Antimicrobial stewardship programs (ASPs) have been introduced in most hospital complexes; however, they are not always useful for pediatric patients. The aim of this study is to investigate the efficacy of direct clinical intervention for infectious diseases by a pediatric infectious disease specialist in a tertiary medical facility without pediatric ASP. This retrospective study included 1,821 patients who were hospitalized in the pediatric ward of a large metropolitan hospital from 2010 to 2015. The clinical course, the use of intravenous antimicrobial agents and the results of a microbiological analysis were compared between the period after the beginning of direct intervention by the specialist (post-intervention period) and the previous period (pre-intervention period). In the post-intervention period, the proportion of the patients who received intravenous antimicrobial agents, the number of antimicrobial agents used for each episode, and the proportion of episodes in which an antimicrobial agent was re-administrated were significantly lower (P = 0.006, P = 0.004, P = 0.036, respectively), and the duration of antimicrobial treatment was significantly shorter (P < 0.001). In addition, narrower spectrum antimicrobial agents were used, and the incidence of meropenem-sensitive Pseudomonas aeruginosa significantly increased (P = 0.037) in the post-intervention period. There was no change of mortality between the two periods. Direct clinical intervention by a pediatric infectious diseases specialist is useful for the treatment of infectious diseases in the pediatric ward of a tertiary medical facility without a pediatric ASP. The creation of a pediatric ASP is recommended in hospital complexes.

Antimicrobial potency of cationic antimicrobial peptides can be predicted from their amino acid composition: Application to the detection of "cryptic" antimicrobial peptides.

PubMed

Pane, Katia; Durante, Lorenzo; Crescenzi, Orlando; Cafaro, Valeria; Pizzo, Elio; Varcamonti, Mario; Zanfardino, Anna; Izzo, Viviana; Di Donato, Alberto; Notomista, Eugenio

2017-04-21

Cationic antimicrobial peptides (CAMPs) are essential components of innate immunity. Here we show that antimicrobial potency of CAMPs is linearly correlated to the product C m H n L where C is the net charge of the peptide, H is a measure of its hydrophobicity and L its length. Exponents m and n define the relative contribution of charge and hydrophobicity to the antimicrobial potency. Very interestingly the values of m and n are strain specific. The ratio n/(m+n) can vary between ca. 0.5 and 1, thus indicating that some strains are sensitive to highly charged peptides, whereas others are particularly susceptible to more hydrophobic peptides. The slope of the regression line describing the correlation "antimicrobial potency"/"C m H n L product" changes from strain to strain indicating that some strains acquired a higher resistance to CAMPs than others. Our analysis provides also an effective computational strategy to identify CAMPs included inside the structure of larger proteins or precursors, which can be defined as "cryptic" CAMPs. We demonstrate that it is not only possible to identify and locate with very good precision the position of cryptic peptides, but also to analyze the internal structure of long CAMPs, thus allowing to draw an accurate map of the molecular determinants of their antimicrobial activity. A spreadsheet, provided in the Supplementary material, allows performing the analysis of protein sequences. Our strategy is also well suited to analyze large pools of sequences, thus significantly improving the identification of new CAMPs and the study of innate immunity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antimicrobial use in paediatric patients in a teaching hospital in Ethiopia

PubMed Central

Kebede, Hafte Kahsay; Gesesew, Hailay Abrha; Woldehaimanot, Tewodros Eyob; Goro, Kabaye Kumela

2017-01-01

Background Antibiotics use in in children are different from adults due to a lack of data on pharmacokinetics, pharmacodynamics, efficacy and safety of drugs, different physiological spectrum, pediatrics populations being vulnerable to the majority of the illnesses, and the adverse effect of their irrational use is more serious. However, antibiotic use is not explored much in a paediatric population. The current study focused on antibiotic use among pediatric population using data from a tertiary hospital in Ethiopia. Methods A retrospective cross-sectional study collated data from 614 pediatrics patients admitted in pediatrics ward at Jimma University Teaching Hospital, Southwest Ethiopia. Descriptive analyses were performed to describe the type and pattern of antibiotics. The number of prescriptions per a patient was also compared with the WHO standard. Data analysis was carried out using SPSS version 20 for mackintosh. Results Antimicrobials were prescribed for 407(86.4%) patients of which 85.9% were in the form of injectables. A total of 1241 (90%) medicines were administered parenterally followed by oral 110 (8%). The maximum number of medicines per prescription was eight for all types of drugs in general, and five for antimicrobials in particular. All antimicrobials were prescribed empirically without any microbiological evidence. Pneumonia, sepsis and meningitis were the main reasons for antimicrobial use in the ward. Out of the total of 812 antibiotics prescribed; Penicillin G crystalline was the most (20%) frequently prescribed, followed by gentamicin (19%) and ampicillin (16). Conclusions Majority of the prescribed antibiotics were antimicrobials, and was in the form of injectables. Antimicrobials were over prescribed and the number of drugs per prescription was also far from WHO recommendation. Strict prescribing standard guidelines and treatment habits should be developed in the country, to prevent antimicrobial resistance. PMID:28264021

Introduction: the goals of antimicrobial therapy.

PubMed

Song, Jae-Hoon

2003-03-01

Antimicrobial agents are generally evaluated in preclinical studies assessing in vitro activity, animal models demonstrating in vivo bacteriologic efficacy, and clinical trials primarily investigating safety and clinical efficacy. However, large sample sizes are required to detect any differences in outcomes between antimicrobials in clinical trials, and, generally, studies are powered to show only clinical equivalence. In addition, diagnosis is often based on clinical symptoms, rather than microbiological evidence of bacterial infection, and the patients most likely to have resistant pathogens are often excluded. Clinical efficacy can be achieved in some bacterial infections in which antimicrobials are suboptimal or even not prescribed. However, bacterial eradication maximizes clinical efficacy and may also reduce the development and spread of resistant organisms. The goal of antimicrobial therapy is, therefore, to eradicate bacteria at the site of infection. Bacterial eradication is not usually assessed as a primary endpoint within the limits of currently recommended clinical trial design. However, pharmacokinetic (PK) (serum concentration profiles, penetration to site of infection) and pharmacodynamic (PD) (susceptibility, concentration- versus time-dependent killing, post-antimicrobial effects) criteria can be used to predict bacteriologic efficacy. PK/PD predictions should be confirmed during all phases of antimicrobial development and throughout clinical use in response to changing patterns of resistance. A clear rationale for dose recommendations can be determined preclinically based on PK/PD parameters, and correlated with efficacy, safety and resistance endpoints in clinical trials. The duration of treatment and dose should be the shortest that will reliably eradicate the pathogen(s), and that is safe and well tolerated. Currently available agents vary significantly in their ability to achieve PK/PD parameters necessary for bacteriologic eradication. Recommendations for appropriate antimicrobial therapy should be based on PK/PD parameters, with the aim of achieving the maximum potential for eradication of both existing and emerging resistant pathogens.

Surveillance of antimicrobial resistance in Lebanese hospitals: retrospective nationwide compiled data.

PubMed

Chamoun, Kamal; Farah, Maya; Araj, Georges; Daoud, Ziad; Moghnieh, Rima; Salameh, Pascale; Saade, Danielle; Mokhbat, Jacques; Abboud, Emme; Hamze, Monzer; Abboud, Edmond; Jisr, Tamima; Haddad, Antoine; Feghali, Rita; Azar, Nadim; El-Zaatari, Mohammad; Chedid, Marwan; Haddad, Christian; Zouain Dib Nehme, Mireille; Barakat, Angelique; Husni, Rola

2016-05-01

Antimicrobial resistance is closely linked to antimicrobial use and is a growing concern worldwide. Antimicrobial resistance increases healthcare costs substantially in many countries, including Lebanon. National data from Lebanon have, in the most part, been limited to a few academic hospitals. The Lebanese Society of Infectious Diseases conducted a retrospective study to better describe the antimicrobial susceptibility patterns of bacterial isolates in Lebanon. Data were based on records retrieved from the bacteriology laboratories of 16 different Lebanese hospitals between January 2011 and December 2013. The susceptibility results of a total 20684 Gram-positive and 55594 Gram-negative bacteria were analyzed. The prevalence rate of methicillin-resistant Staphylococcus aureus was 27.6% and of vancomycin-resistant Enterococcus spp was 1%. Streptococcus pneumoniae had susceptibilities of 46% to oxacillin, 63% to erythromycin, and 98% to levofloxacin. Streptococcus pyogenes had susceptibilities of 94% to erythromycin and 95% to clindamycin. The mean ampicillin susceptibility of Haemophilus influenzae, Salmonella spp, and Shigella spp isolates was 79%, 81.3%, and 62.2%, respectively. The extended-spectrum beta-lactamase production rate for Escherichia coli was 32.3% and for Klebsiella spp was 29.2%. Acinetobacter spp showed high resistance to most antimicrobials, with low resistance to colistin (17.1%). Pseudomonas spp susceptibilities to piperacillin-tazobactam and imipenem were lower than 80% (79.7% and 72.8%, respectively). This study provides population-specific data that are valuable in guiding antimicrobial use in Lebanon and neighbouring countries and will help in the establishment of a surveillance system for antimicrobial resistance following the implementation of a nationwide standardization of laboratory methods and data entry. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Patterns and predictors of antimicrobial resistance among Staphylococcus spp. from canine clinical cases presented at a veterinary academic hospital in South Africa.

PubMed

Qekwana, Daniel N; Oguttu, James W; Sithole, Fortune; Odoi, Agricola

2017-04-28

Antimicrobial resistance in staphylococci, often associated with treatment failure, is increasingly reported in veterinary medicine. The aim of this study was to investigate patterns and predictors of antimicrobial resistance among Staphylococcus spp. isolates from canine samples submitted to the bacteriology laboratory at the University of Pretoria academic veterinary hospital between 2007 and 2012. Retrospective data of 334 Staphylococcus isolates were used to calculate the proportion of samples resistant to 15 antimicrobial agents. The Cochran-Armitage trend test was used to investigate temporal trends and logistic regression models were used to investigate predictors of antimicrobial resistance in Staphylococcus aureus and Staphylococcus pseudintermedius. Results show that 98.2% (55/56) of the S. aureus isolates were resistant to at least one drug while 42.9% were multidrug resistant. Seventy-seven percent (214/278) of the S. pseudintermedius isolates were resistant to at least one drug and 25.9% (72/278) were multidrug resistant. Resistance to lincospectin was more common among S. aureus (64.3%) than S. pseudintermedius (38.9%). Similarly, resistance to clindamycin was higher in S. aureus (51.8%) than S. pseudintermedius (31.7%) isolates. There was a significant (p = 0.005) increase in S. aureus resistance to enrofloxacin over the study period. Similarly, S. pseudintermedius exhibited significant increasing temporal trend in resistance to trimethoprim-sulphamethoxazole (p = 0.004), clindamycin (p = 0.022) and orbifloxacin (p = 0.042). However, there was a significant decreasing temporal trend in the proportion of isolates resistant to doxycycline (p = 0.041), tylosin (p = 0.008), kanamycin (p = 0.017) and amoxicillin/clavulanic acid (p = 0.032). High levels of multidrug resistance and the increasing levels of resistance to sulphonamides, lincosamides and fluoroquinolones among Staphylococcus spp. isolates in this study are concerning. Future studies will need to investigate local drivers of antimicrobial resistance to better guide control efforts to address the problem.

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.

Cost-effectiveness analysis of implementing an antimicrobial stewardship program in critical care units.

PubMed

Ruiz-Ramos, Jesus; Frasquet, Juan; Romá, Eva; Poveda-Andres, Jose Luis; Salavert-Leti, Miguel; Castellanos, Alvaro; Ramirez, Paula

2017-06-01

To evaluate the cost-effectiveness of antimicrobial stewardship (AS) program implementation focused on critical care units based on assumptions for the Spanish setting. A decision model comparing costs and outcomes of sepsis, community-acquired pneumonia, and nosocomial infections (including catheter-related bacteremia, urinary tract infection, and ventilator-associated pneumonia) in critical care units with or without an AS was designed. Model variables and costs, along with their distributions, were obtained from the literature. The study was performed from the Spanish National Health System (NHS) perspective, including only direct costs. The Incremental Cost-Effectiveness Ratio (ICER) was analysed regarding the ability of the program to reduce multi-drug resistant bacteria. Uncertainty in ICERs was evaluated with probabilistic sensitivity analyses. In the short-term, implementing an AS reduces the consumption of antimicrobials with a net benefit of €71,738. In the long-term, the maintenance of the program involves an additional cost to the system of €107,569. Cost per avoided resistance was €7,342, and cost-per-life-years gained (LYG) was €9,788. Results from the probabilistic sensitivity analysis showed that there was a more than 90% likelihood that an AS would be cost-effective at a level of €8,000 per LYG. Wide variability of economic results obtained from the implementation of this type of AS program and short information on their impact on patient evolution and any resistance avoided. Implementing an AS focusing on critical care patients is a long-term cost-effective tool. Implementation costs are amortized by reducing antimicrobial consumption to prevent infection by multidrug-resistant pathogens.

Quantitative analysis of catechins in Saraca asoca and correlation with antimicrobial activity

PubMed Central

Shirolkar, Amey; Gahlaut, Anjum; Chhillar, Anil K.; Dabur, Rajesh

2013-01-01

Herbal medicines are highly complex and have unknown mechanisms in diseases treatment. Saraca asoca (Roxb.), De. Wild has been recommended to treat gynecological disorders and used in several commercial polyherbal formulations. In present study, efforts have been made to explore antimicrobial activity and its co-relation with the distributions of catechins in the organs of S. asoca using targeted MS/MS. Eight extracts (cold and hot water) from four different organs of S. asoca and two drugs were prepared and antimicrobial activity was assessed by microbroth dilution assay. Quantitative and qualitative analysis of catechins in crude extracts was done by using targeted and auto-MS/MS and correlated with antimicrobial activity. (+)-Catechin and (+)-epicatechin and their biosynthesis related compound were found to be up-regulated in regenerated bark and leaves extracts. (−)-Epigallocatechin was found to be significantly higher in bark water extract as compared to others but showed low antimicrobial activity. Result showed down-regulation of (−)-epigallocatechin and up-regulation of (+)-catechin and (+)-epicatechin in the regenerated bark and leaves of S. asoca. It might be the contributing factor in the antimicrobial activity of regenerated bark and leaves of the plant. The concentration of (+)-epicatechin in processed drugs (Ashokarishta) from Baidyanath was found to be seven times higher than that of Dabur Pvt. Ltd., but no antimicrobial activity was observed, indicating the variations among the plant based drugs. This will be helpful in rational use of S. asoca parts. Furthermore, the analytical method developed is sensitive, repeatable and reliable; therefore, it is suitable for quality control of herbal drugs. PMID:29403849

Supercritical carbon dioxide extraction of compounds with antimicrobial activity from Origanum vulgare L.: determination of optimal extraction parameters.

PubMed

Santoyo, S; Cavero, S; Jaime, L; Ibañez, E; Señoráns, F J; Reglero, G

2006-02-01

Oregano leaves were extracted using a pilot-scale supercritical fluid extraction plant under a wide range of extraction conditions, with the goal of determining the extraction and fractionation conditions to obtain extracts with optimal antimicrobial activity. In this investigation, the essential oil-rich fractions were selectively precipitated in the second separator, and their chemical composition and antimicrobial activity were investigated. Gas chromatography-mass spectrometry analysis of the various fractions resulted in the identification of 27 compounds of the essential oil. The main components of these fractions were carvacrol, trans-sabinene hydrate, cis-piperitol, borneol, terpinen-4-ol, and linalool. Antimicrobial activity was investigated by the disk diffusion and broth dilution methods against six different microbial species, including two gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), two gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), a yeast (Candida albicans), and a fungus (Aspergillus niger). All of the supercritical fluid extraction fractions obtained showed antimicrobial activity against all of the microorganisms tested, although the most active fraction was the one obtained in experiment 5 (fraction was obtained with 7% ethanol at 150 bar and 40 degrees C). C. albicans was the most sensitive microorganism to the oregano extracts, whereas the least susceptible was A. niger. Carvacrol, sabinene hydrate, borneol, and linalool standards also showed antimicrobial activity against all of the microorganisms tested, with carvacrol being the most effective. Consequently, it was confirmed that essential oil from experiment 5, with the best antimicrobial activity, also presented the highest quantity of carvacrol.

Antimicrobial activity of organotin(IV) complexes with the ligand benzil bis(benzoylhydrazone) and 4,4'-bipyridyl as coligand.

PubMed

López-Torres, Elena; Zani, Franca; Mendiola, M Antonia

2011-05-01

Several methyltin(IV) and butyltin(IV) complexes with the ligand benzil bis(benzoylhydrazone) and 4,4'-bipyridyl as coligand were synthesised and characterized by elemental analysis and by IR, (1)H, (13)C and (119)Sn NMR spectroscopies. Some of them were also analyzed using single crystal X-ray diffraction. The title compounds were evaluated for their in vitro antimicrobial properties. All buthyltin complexes showed significant inhibition of Gram positive bacteria, resulting Bacillus subtilis, Sarcina lutea and both methicillin-susceptible and methicillin-resistant Staphylococcus epidermidis the most sensitive strains. Furthermore, they were able to inhibit the growth of Gram negative bacteria, especially Proteus vulgaris, whereas no activity was exhibited against fungi. All methyltin complexes were devoid of antimicrobial properties. Copyright © 2011 Elsevier Inc. All rights reserved.

Successful control of resistance in Pseudomonas aeruginosa using antibiotic stewardship and infection control programs at a Chinese university hospital: a 6-year prospective study.

PubMed

Liu, Lei; Liu, Bin; Li, Yu; Zhang, Wei

2018-01-01

Pseudomonas aeruginosa is emerging as a highly multidrug-resistant (MDR) nosocomial pathogen. Data on the efficacy of infection control measures in endemic situations are lacking. We investigated the effect of antimicrobial stewardship (AMS) and infection control programs (ICPs) in controlling the resistance of P. aeruginosa at a tertiary hospital center. Susceptibility and resistance were investigated using broth microdilution, as per the guidelines of the Clinical and Laboratory Standards Institute. Antibiotic use was restricted through AMS, which included a classification management system for antibiotic use. The ICPs included environmental cleaning and disinfection, hand hygiene, active surveillance of P . aeruginosa, and education about infection control. A total of 2,241 P. aeruginosa isolates were evaluated between 2012 and 2017. Sensitivity and resistance of the isolates to the antipseudomonal antimicrobials colistin and tigecycline were stable. The sensitivity and resistance to other antipseudomonal antimicrobials improved after 2014, after the AMS and ICPs were implemented in 2013. The use of alcohol-based hand gel significantly increased from 0.6 to 10.9 L per 1,000 patient-days (PD) during the study period ( P =0.005). The incidence rates of extensively drug-resistant (XDR) and MDR P. aeruginosa showed a sustained decrease from 2013 (4.9 and 22%) to 2017 (1 and 15%), respectively. The yearly consumption of antimicrobial agents also showed a sustained and significant decrease from 45 defined daily doses (DDDs) per 1,000 PD to 38.15 DDDs per 1,000 PD ( P =0.04). A significant correlation was found between the incidence rate of MDR P. aeruginosa and the consumption of antimicrobial agents ( P =0.01). Monitoring of P. aeruginosa , AMS, and comprehensive ICPs could be one of the best and effective methods to prevent the development of resistance in P. aeruginosa .

Throat carriage rate and antimicrobial susceptibility pattern of group A Streptococci (GAS) in healthy Ethiopian school children.

PubMed

Abdissa, Alemseged; Asrat, Daniel; Kronvall, Göran; Shitu, Belay; Achiko, Dilachew; Zeidan, Mohammed; Yamuah, Lawrence K; Aseffa, Abraham

2011-04-01

Group A Streptococci (GAS) or Streptococcus pyogenes are the most frequent cause of pharyngitis and skin infection in children and lead to post infection complications including acute rheumatic fever and glomerulonephritis. Pharyngeal carriage rates of GAS among healthy school children vary with geographical location and seasons. There is not much information on the screening of children for carriage of GAS in Ethiopia. The study aimed at assessing the carriage rate of Group A Streptococci and antimicrobial susceptibility of the isolates in healthy Ethiopian school children. A total of 937 children residing in Addis Ababa (n=491), Gondar (n=265) and Dire-Dawa (n=181) were investigated during a period between November 2004 and January 2005. Throat specimens were collected and cultured using standard procedure. Beta haemolytic streptococci were serogrouped by agglutination tests using specific antisera. Antimicrobial susceptibility testing of the isolates was performed by diffusion method. The median and the mean ages of the study participants were 11 (range 6-14) years. Girls constituted 52% (486/937) of the study participants. A total of 167 (17.8%) beta haemolytic streptococci were recovered from 937 children investigated GAS accounted for 91/167 (54.5%) of beta hemolytic streptococcal isolates. The carrier rate for GAS was 9.7% (91/937) of the screened children followed by group G with 3.2% (30/937) and group C streptococci with 2.2% (21/937). All GAS isolates were sensitive to oxacillin, penicillin, erythromycin, clindamycin and trimethoprim-sulphamethoxazole. Lower frequency of resistance was observed against tetracycline and vanocmycin. The present study revealed that GAS was the most predominant beta-haemolytic streptococcus among healthy Ethiopian school children. Our results showed that pharyngeal carriage of GAS in school children should not be underestimated. Therefore it is recommended to conduct regular screening and GAS surveillance in schools, and maintain rational use of antibiotics to minimize GAS resistance.

Occurrence of antimicrobial-resistant salmonella species in raw and ready to eat turkey meat products from retail outlets in the midwestern United States.

PubMed

Khaitsa, Margaret L; Kegode, Redempta B; Doetkott, Dawn K

2007-01-01

To investigate occurrence of Salmonella in raw and ready to eat (RTE) turkey from retail outlets, determine factors associated with its occurrence and antimicrobial-resistance patterns. A total of 959 turkey products (raw, n = 345; and RTE, n = 614) were purchased in 3 months from four stores in one city in the midwestern United States. Chi-square and logistic regression analyses were used to test for associations of microbial contamination with product type and brand, expiration date, sampling time, and retail store. Antimicrobial resistance of Salmonellae was determined using a National Antimicrobial Resistance Monitoring System (NARMS) panel of antimicrobials. Overall, 2.2% (21/959) of the samples (4.1% [14/345] raw and 1.1% [7/614] RTE) were contaminated with Salmonella. A significant difference in Salmonella occurrence (p < 0.05), between meat type (raw vs. RTE; OR = 4.2, 95% CI = 1.6, 10.8); and sampling month (p < 0.05) was reported, but not between retail stores and product brands. Salmonellae belonged to 6 serotypes: Hadar, Heidelberg, Typhimurium var. Copenhagen, Newport, Saintpaul, and Agona. Salmonellae from raw turkey exhibited higher antimicrobial resistance (53%) compared to those from RTE products (33%). Multidrug resistance was exhibited by 62% of Salmonellae (86% RTE, 50% raw meats). CONCLUSION AND CLINICAL APPLICATIONS: Turkey (both raw and RTE) may occasionally be contaminated with antimicrobial-resistant Salmonellae whose occurrence was influenced by sampling month and meat type. Continued surveillance of Salmonella occurrence in meat products, in particular RTE ones, is warranted in order to ensure a safe food supply.

The livestock reservoir for antimicrobial resistance: a personal view on changing patterns of risks, effects of interventions and the way forward.

PubMed

Aarestrup, Frank M

2015-06-05

The purpose of this review was to provide an updated overview on the use of antimicrobial agents in livestock, the associated problems for humans and current knowledge on the effects of reducing resistance in the livestock reservoir on both human health and animal production. There is still limiting data on both use of antimicrobial agents, occurrence and spread of resistance as well as impact on human health. However, in recent years, emerging issues related to methicillin-resistant Staphylococcus aureus, Clostridium difficile, Escherichia coli and horizontally transferred genes indicates that the livestock reservoir has a more significant impact on human health than was estimated 10 years ago, where the focus was mainly on resistance in Campylobacter and Salmonella. Studies have indicated that there might only be a marginal if any benefit from the regular use of antibiotics and have shown that it is possible to substantially reduce the use of antimicrobial agents in livestock production without compromising animal welfare or health or production. In some cases, this should be done in combination with other measures such as biosecurity and use of vaccines. To enable better studies on both the global burden and the effect of interventions, there is a need for global harmonized integrated and continuous surveillance of antimicrobial usage and antimicrobial resistance, preferably associated with data on production and animal diseases to determine the positive and negative impact of reducing antimicrobial use in livestock. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Antimicrobial Susceptibility Patterns of Brachyspira Species Isolated from Swine Herds in the United States

PubMed Central

Mirajkar, Nandita S.; Davies, Peter R.

2016-01-01

Outbreaks of swine dysentery, caused by Brachyspira hyodysenteriae and the recently discovered “Brachyspira hampsonii,” have reoccurred in North American swine herds since the late 2000s. Additionally, multiple Brachyspira species have been increasingly isolated by North American diagnostic laboratories. In Europe, the reliance on antimicrobial therapy for control of swine dysentery has been followed by reports of antimicrobial resistance over time. The objectives of our study were to determine the antimicrobial susceptibility trends of four Brachyspira species originating from U.S. swine herds and to investigate their associations with the bacterial species, genotypes, and epidemiological origins of the isolates. We evaluated the susceptibility of B. hyodysenteriae, B. hampsonii, Brachyspira pilosicoli, and Brachyspira murdochii to tiamulin, valnemulin, doxycycline, lincomycin, and tylosin by broth microdilution and that to carbadox by agar dilution. In general, Brachyspira species showed high susceptibility to tiamulin, valnemulin, and carbadox, heterogeneous susceptibility to doxycycline, and low susceptibility to lincomycin and tylosin. A trend of decreasing antimicrobial susceptibility by species was observed (B. hampsonii > B. hyodysenteriae > B. murdochii > B. pilosicoli). In general, Brachyspira isolates from the United States were more susceptible to these antimicrobials than were isolates from other countries. Decreased antimicrobial susceptibility was associated with the genotype, stage of production, and production system from which the isolate originated, which highlights the roles of biosecurity and husbandry in disease prevention and control. Finally, this study also highlights the urgent need for Clinical and Laboratory Standards Institute-approved clinical breakpoints for Brachyspira species, to facilitate informed therapeutic and control strategies. PMID:27252458

Antimicrobial Susceptibility Patterns of Brachyspira Species Isolated from Swine Herds in the United States.

PubMed

Mirajkar, Nandita S; Davies, Peter R; Gebhart, Connie J

2016-08-01

Outbreaks of swine dysentery, caused by Brachyspira hyodysenteriae and the recently discovered "Brachyspira hampsonii," have reoccurred in North American swine herds since the late 2000s. Additionally, multiple Brachyspira species have been increasingly isolated by North American diagnostic laboratories. In Europe, the reliance on antimicrobial therapy for control of swine dysentery has been followed by reports of antimicrobial resistance over time. The objectives of our study were to determine the antimicrobial susceptibility trends of four Brachyspira species originating from U.S. swine herds and to investigate their associations with the bacterial species, genotypes, and epidemiological origins of the isolates. We evaluated the susceptibility of B. hyodysenteriae, B. hampsonii, Brachyspira pilosicoli, and Brachyspira murdochii to tiamulin, valnemulin, doxycycline, lincomycin, and tylosin by broth microdilution and that to carbadox by agar dilution. In general, Brachyspira species showed high susceptibility to tiamulin, valnemulin, and carbadox, heterogeneous susceptibility to doxycycline, and low susceptibility to lincomycin and tylosin. A trend of decreasing antimicrobial susceptibility by species was observed (B. hampsonii > B. hyodysenteriae > B. murdochii > B. pilosicoli). In general, Brachyspira isolates from the United States were more susceptible to these antimicrobials than were isolates from other countries. Decreased antimicrobial susceptibility was associated with the genotype, stage of production, and production system from which the isolate originated, which highlights the roles of biosecurity and husbandry in disease prevention and control. Finally, this study also highlights the urgent need for Clinical and Laboratory Standards Institute-approved clinical breakpoints for Brachyspira species, to facilitate informed therapeutic and control strategies. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Antibiotic Screening of Urine Culture for Internal Quality Audit at Amrita Hospital, Kochi.

PubMed

Suresh, Aswathy; Gopinathan, Anusha; Dinesh, Kavitha R; Kumar, Anil

2017-07-01

Urine antimicrobial activity is a seldom analysed laboratory test which greatly impacts the quantification of urine specimens. Presence of antimicrobial activity in the urine reduces the bacterial load in these specimens. Hence, the chances of erroneously reporting insignificant bacteriuria can be reduced on analysis of the antimicrobial activity in urine. The aim of the study was to measure the antimicrobial activity of urine samples obtained from patients in a tertiary care hospital. A total of 100 urine specimens were collected from the study group. Tests like wet mount, Gram staining and culture were performed. Antimicrobial susceptibility testing was done on the bacteria isolated from each specimen. The urine specimens were reported as significant bacteriuria (>105 Colony Forming Unit (CFU)/ml) and insignificant bacteriuria (<105 CFU/ml - clean catch midstream urine; <102 CFU/ml - catheterized urine sample) according to the CFU/ml. Staphylococcus aureus ATCC ® 25923 ™ and Escherichia coli ATCC ® 25922 ™ were used to identify the presence of antimicrobial activity in the urine sample by Urine Anti-Bacterial substance Assay (UABA). McNemar test was used for statistical analysis using Statistical Package for the Social Sciences (SPSS) version 21.0. On analysis of the antimicrobial activity of urine sample with the prior antibiotic history of the patients, 17 were true positives and 43 were true negatives. Twenty six of samples with UABA positivity were culture negative and 28 samples with UABA positivity were culture positive. Sensitivity and specificity of the test was 85% and 53.8% respectively. Accuracy of the test was 60%. The p-value of UABA was <0.001. Enterobacteriaceae was the most common bacterial family isolated from the urine specimens. A total of 85% patients responded to treatment. Presence of antimicrobial activity in urine has a great impact on the interpretation of urine culture reports. Identification of urine antimicrobial activity helps in evaluating the quantification of bacterial growth reported in urine culture. It facilitates speedy recovery of patients by early administration of antibiotics.

Prevalence and antimicrobial susceptibility patterns of extended spectrum beta-lactamase producing Entrobacteriaceae in the University of Gondar Referral Hospital environments, northwest Ethiopia.

PubMed

Engda, Tigist; Moges, Feleke; Gelaw, Aschalew; Eshete, Setegn; Mekonnen, Feleke

2018-05-22

This study aimed at assessing the magnitude, distribution, and the antimicrobial susceptibility of the extended spectrum beta-lactamase producing Entrobacteriaceae in the University of Gondar Referral Hospital environments. Out of a total of 384 samples, 14.8% were ESBL producing Entrobacteriaceae, where 42.10% Klebsiella pneumoniae, 35.09% Escherchia coli and 7.01% Proteus mirabilis were the predominant isolates. Most ESBL producing isolates, that is, 24.56, 22.8, and 22.8% were found from waste water, sinks and bedside tables respectively. All ESBL producing Entrobacteriaceae were found to be resistant to ceftriaxone, ceftazidime, cefpirome, cefpodoxime, and amoxicillin with Clavulanic acid. Resistance rate was also high for non-beta-lactam antimicrobials, like chloramphenicol (70.18%), cotrimoxazole (64.91%), norfloxacin (42.10%), ciprofloxacin (43.86%), and gentamicin (19.30%).

Antimicrobial properties of ternary eutectic aluminum alloys.

PubMed

Hahn, Claudia; Hans, Michael; Hein, Christina; Dennstedt, Anne; Mücklich, Frank; Rettberg, Petra; Hellweg, Christine Elisabeth; Leichert, Lars Ingo; Rensing, Christopher; Moeller, Ralf

2018-06-27

Several Escherichia coli deletion mutants of the Keio collection were selected for analysis to better understand which genes may play a key role in copper or silver homeostasis. Each of the selected E. coli mutants had a deletion of a single gene predicted to encode proteins for homologous recombination or contained functions directly linked to copper or silver transport or transformation. The survival of these strains on pure copper surfaces, stainless steel, and alloys of aluminum, copper and/or silver was investigated. When exposed to pure copper surfaces, E. coli ΔcueO was the most sensitive, whereas E. coli ΔcopA was the most resistant amongst the different strains tested. However, we observed a different trend in sensitivities in E. coli strains upon exposure to alloys of the system Al-Ag-Cu. While minor antimicrobial effects were detected after exposure of E. coli ΔcopA and E. coli ΔrecA to Al-Ag alloys, no effect was detected after exposure to Al-Cu alloys. The release of copper ions and cell-associated copper ion concentrations were determined for E. coli ΔcopA and the wild-type E. coli after exposure to pure copper surfaces. Altogether, compared to binary alloys, ternary eutectic alloys (Al-Ag-Cu) had the highest antimicrobial effect and thus, warrant further investigation.

Antimicrobial Resistance Risks of Cholera Prophylaxis for United Nations Peacekeepers

PubMed Central

Lewnard, Joseph A.; Pitzer, Virginia E.; Cohen, Ted

2017-01-01

ABSTRACT More than 5 years after a United Nations peacekeeping battalion introduced cholera to Haiti, over 150,000 peacekeepers continue to be deployed annually from countries where cholera is endemic. The United Nations has thus far declined to provide antimicrobial chemoprophylaxis to peacekeepers, a policy based largely on concerns that the risks of drug resistance generation and spread would outweigh the potential benefits of preventing future cholera importations. In this study, we sought to better understand the relative benefits and risks of cholera chemoprophylaxis for peacekeepers in terms of antibiotic resistance. Using a stochastic model to quantify the potential impact of chemoprophylaxis on importation and transmission of drug-resistant and drug-sensitive Vibrio cholerae, we found that chemoprophylaxis would decrease the probability of cholera importation but would increase the expected number of drug-resistant infections if an importation event were to occur. Despite this potential increase, we found that at least 10 drug-sensitive infections would likely be averted per excess drug-resistant infection under a wide range of assumptions about the underlying prevalence of drug resistance and risk of acquired resistance. Given these findings, policymakers should reconsider whether the potential resistance risks of providing antimicrobial chemoprophylaxis to peacekeepers are sufficient to outweigh the anticipated benefits. PMID:28533237

Rauvolfia Grandiflora (Apocynaceae) Extract Interferes With Staphylococcal Density, Enterotoxin Production And Antimicrobial Activity

PubMed Central

de Almeida Carlos, Lanamar; da Silva Amaral, Kenas Aguiar; Curcino Vieira, Ivo José; Mathias, Leda; Braz-Filho, Raimundo; Silva Samarão, Solange; Vieira-da-Motta, Olney

2010-01-01

Staphylococci bacteria are involved in many human and animal infections and development of alternative antimicrobial drugs against pathogenic bacteria is of great interest to the pharmaceutical industry. This study investigated the in vitro effect of Rauvolfia grandiflora methanol extract (root bark fraction) (RGE) on the density of ATCC strains of Staphylococcus aureus and Staphylococcus epidermidis, and a clinical enterotoxin-producer, S. aureus bovine strain. The alkaloid, isoreserpiline, obtained from dichloromethane extract of R. grandiflora was ineffective against the strains tested. After incubation of staphylococci strains in the presence of 1.2 μg.mL-1 RGE, a significant inhibition of cell growth was observed using both spectrophotometry and ELISA assays. Twelve drugs were evaluated for their antimicrobial effects on culture RGE-treated cells using the disk diffusion method. Penicillin resistant strains became sensitive to the drug after RGE treatment. Furthermore, enterotoxin production by RGE-treated S. aureus was evaluated using a standardized ELISA method. Although staphylococcal LSA 88 bovine strain cells remained viable after exposure to the extract, enterotoxin production was precluded in 20% after RGE treatment. Significant interference in staphylococci cell density, drug sensitivity and enterotoxin secretion was observed after treatment. The study highlights the necessity to find new methods of disease prevention and new antibiotic therapies against staphylococcal infections. PMID:24031536

Rauvolfia grandiflora (apocynaceae) extract interferes with staphylococcal density, enterotoxin production and antimicrobial activity.

PubMed

de Almeida Carlos, Lanamar; da Silva Amaral, Kenas Aguiar; Curcino Vieira, Ivo José; Mathias, Leda; Braz-Filho, Raimundo; Silva Samarão, Solange; Vieira-da-Motta, Olney

2010-07-01

Staphylococci bacteria are involved in many human and animal infections and development of alternative antimicrobial drugs against pathogenic bacteria is of great interest to the pharmaceutical industry. This study investigated the in vitro effect of Rauvolfia grandiflora methanol extract (root bark fraction) (RGE) on the density of ATCC strains of Staphylococcus aureus and Staphylococcus epidermidis, and a clinical enterotoxin-producer, S. aureus bovine strain. The alkaloid, isoreserpiline, obtained from dichloromethane extract of R. grandiflora was ineffective against the strains tested. After incubation of staphylococci strains in the presence of 1.2 μg.mL(-1) RGE, a significant inhibition of cell growth was observed using both spectrophotometry and ELISA assays. Twelve drugs were evaluated for their antimicrobial effects on culture RGE-treated cells using the disk diffusion method. Penicillin resistant strains became sensitive to the drug after RGE treatment. Furthermore, enterotoxin production by RGE-treated S. aureus was evaluated using a standardized ELISA method. Although staphylococcal LSA 88 bovine strain cells remained viable after exposure to the extract, enterotoxin production was precluded in 20% after RGE treatment. Significant interference in staphylococci cell density, drug sensitivity and enterotoxin secretion was observed after treatment. The study highlights the necessity to find new methods of disease prevention and new antibiotic therapies against staphylococcal infections.

Antimicrobial Resistance Risks of Cholera Prophylaxis for United Nations Peacekeepers.

PubMed

Kunkel, Amber; Lewnard, Joseph A; Pitzer, Virginia E; Cohen, Ted

2017-08-01

More than 5 years after a United Nations peacekeeping battalion introduced cholera to Haiti, over 150,000 peacekeepers continue to be deployed annually from countries where cholera is endemic. The United Nations has thus far declined to provide antimicrobial chemoprophylaxis to peacekeepers, a policy based largely on concerns that the risks of drug resistance generation and spread would outweigh the potential benefits of preventing future cholera importations. In this study, we sought to better understand the relative benefits and risks of cholera chemoprophylaxis for peacekeepers in terms of antibiotic resistance. Using a stochastic model to quantify the potential impact of chemoprophylaxis on importation and transmission of drug-resistant and drug-sensitive Vibrio cholerae , we found that chemoprophylaxis would decrease the probability of cholera importation but would increase the expected number of drug-resistant infections if an importation event were to occur. Despite this potential increase, we found that at least 10 drug-sensitive infections would likely be averted per excess drug-resistant infection under a wide range of assumptions about the underlying prevalence of drug resistance and risk of acquired resistance. Given these findings, policymakers should reconsider whether the potential resistance risks of providing antimicrobial chemoprophylaxis to peacekeepers are sufficient to outweigh the anticipated benefits. Copyright © 2017 American Society for Microbiology.

Recombinant human DNase I decreases biofilm and increases antimicrobial susceptibility in staphylococci

PubMed Central

Kaplan, Jeffrey B.; LoVetri, Karen; Cardona, Silvia T.; Madhyastha, Srinivasa; Sadovskaya, Irina; Jabbouri, Saïd; Izano, Era A.

2011-01-01

Extracellular DNA is an adhesive component of staphylococcal biofilms. The aim of this study was to evaluate the antibiofilm activity of recombinant human DNase I (rhDNase) against Staphylococcus aureus and Staphylococcus epidermidis. Using a 96-well microtiter plate crystal violet binding assay, we found that biofilm formation by S. aureus was efficiently inhibited by rhDNase at 1–4 μg l−1, and pre-formed S. aureus biofilms were efficiently detached in 2 min by rhDNase at 1 mg l−1. Pre-treatment of S. aureus biofilms for 10 min with 10 mg l−1 rhDNase increased their sensitivity to biocide killing by 4–5 log units. rhDNase at 10 mg l−1 significantly inhibited biofilm formation by S. epidermidis in medium supplemented with subminimal inhibitory concentrations of antibiotics. We also also found rhDNase significantly increased the survival of S. aureus-infected C. elegans nematodes treated with tobramycin compared to nematodes treated with tobramycin alone. We concluded that rhDNase exhibits potent antibiofilm and antimicrobial-sensitizing activities against S. aureus and S. epidermidis at clinically achievable concentrations. rhDNase, either alone or in combination with antimicrobial agents, may have applications in treating or preventing staphylococcal biofilm-related infections. PMID:22167157

In-vitro susceptibility of 400 isolates of Neisseria gonorrhoeae in Vancouver, 1982-84.

PubMed Central

Bowie, W R; Shaw, C E; Chan, D G; Jones, H D; Black, W A

1986-01-01

Consecutive isolates of Neisseria gonorrhoeae obtained at a sexually transmitted disease clinic in Vancouver between June 1982 and June 1984 were tested for in-vitro susceptibility to eight antimicrobial agents. Of the 400 isolates 6 (1.5%) were penicillinase-producing N. gonorrhoeae, and for 25 (6.2%) the minimum inhibitory concentrations (MICs) of penicillin were 1.0 to 4.0 micrograms/ml. Ceftriaxone sodium was the most active agent. The MICs were higher than those reported in a Canadian study in 1973-74, except for tetracycline hydrochloride. The patterns of susceptibility of the isolates to one antimicrobial agent correlated significantly with those to each other agent, although the relation was weakest for trimethoprim-sulfamethoxazole and spectinomycin. The results reinforce the need to evaluate local in-vitro susceptibility patterns, especially since the proportion of isolates with relative and absolute resistance to penicillin is increasing. PMID:3091234

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.

Clinical outcomes of nalidixic acid, ceftriaxone, and multidrug-resistant nontyphoidal salmonella infections compared with pansusceptible infections in FoodNet sites, 2006-2008.

PubMed

Krueger, Amy L; Greene, Sharon A; Barzilay, Ezra J; Henao, Olga; Vugia, Duc; Hanna, Samir; Meyer, Stephanie; Smith, Kirk; Pecic, Gary; Hoefer, Dina; Griffin, Patricia M

2014-05-01

Nontyphoidal Salmonella causes an estimated 1.2 million infections, 23,000 hospitalizations, and 450 deaths annually in the United States. Most illnesses are self-limited; however, treatment with antimicrobial agents can be life-saving for invasive infections. The Foodborne Diseases Active Surveillance Network and the National Antimicrobial Resistance Monitoring System collaborated on a prospective cohort study of patients with nontyphoidal Salmonella bloodstream and gastrointestinal infections to determine differences in the clinical outcomes of resistant compared with pansusceptible infections. Interviews were conducted within 85 days of specimen collection date. Of 875 nontyphoidal Salmonella isolates, 705 (81%) were pansusceptible, 165 (19%) were resistant to at least 1 agent, and 5 (0.6%) had only intermediate resistance. The most common pattern, found in 51 (31%) of resistant isolates, was resistance to at least ampicillin, chloramphenicol, streptomycin, sulfisoxazole, and tetracycline (ACSSuT); 88% of isolates with this pattern were serotype Typhimurium or Newport. Fourteen (52%) of the 27 ceftriaxone-resistant isolates were also ACSSuT resistant. Adjusted for age and serotype, bloodstream infection was significantly more common among patients infected with strains resistant to only two, only three, or only five antimicrobial classes, to ACSSuT with or without other agents, to ACSSuT only, or to nalidixic acid with or without other agents than among patients with pansusceptible isolates. Adjusted for age, serotype, and bloodstream infection, hospitalization was significantly more common among patients infected with strains resistant to only three agents or to ceftriaxone (all ceftriaxone-resistant isolates were resistant to other agents) than among patients with pansusceptible isolates. This study extends evidence that patients with antimicrobial-resistant nontyphoidal Salmonella infections have more severe outcomes. Prevention efforts are needed to reduce unnecessary antimicrobial use in patient care settings and in food animals to help prevent the emergence of resistance and infections with resistant nontyphoidal Salmonella.

Cardiac Electrophysiology Laboratories: A Potential Target for Antimicrobial Stewardship and Quality Improvement?

PubMed

Branch-Elliman, Westyn; Stanislawski, Maggie; Strymish, Judith; Barón, Anna E; Gupta, Kalpana; Varosy, Paul D; Gold, Howard S; Ho, P Michael

2016-09-01

BACKGROUND Infections following cardiovascular implantable electronic device (CIED) procedures, including pacemaker and implantable cardioverter-defibrillators, are devastating and costly. Preimplantation prophylactic antimicrobials are effective for reducing postprocedural infections. However, routine postprocedural antimicrobials are not associated with improved outcomes, and they may be harmful. Thus, we sought to characterize antimicrobial use patterns following CIED procedures. DESIGN All patients who underwent CIED procedures from October 1, 2007 to September 30, 2013 and had procedural information entered into the VA Clinical Assessment Reporting and Tracking (CART) software program were included in this study. All antibiotic prescriptions lasting more than 24 hours following device implantation or revision were identified using pharmacy databases, and postprocedural antibiotic use lasting more than 24 hours was characterized. RESULTS In total, 3,712 CIED procedures were performed at 34 VA facilities on 3,570 patients with a mean age of 71.7 years (standard deviation [SD], 11.1 years), 98.4% of whom were male. Postprocedural antibiotics >24 hours were prescribed following 1,579 of 3,712 CIED procedures (42.5%). The median duration of therapy was 5 days (interquartile range [IQR], 3-7 days). The most commonly prescribed antibiotic was cephalexin (1,152 of 1,579; 72.9%), followed by doxycycline (118 of 1,579; 7.47%) and ciprofloxacin (93 of 1,579; 5.9%). Vancomycin was used in 73 of 1,579 prescriptions (4.62%). Among the highest quartile of procedural volume, prescribing practices varied considerably, ranging from 3.2% to 77.6%. CONCLUSIONS Nearly 1 in 2 patients received prolonged postprocedural antimicrobial therapy following CIED procedures, and the rate of postprocedural antimicrobial therapy use varied considerably by facility. Given the lack of demonstrated benefit of routine prolonged antimicrobial therapy following CIED procedures, antimicrobial use following cardiac device interventions may be a potential target for quality improvement programs and antimicrobial stewardship. Infect Control Hosp Epidemiol 2016;37:1005-1011.

Antimicrobials usage assessments in commercial poultry and local birds in North-central Nigeria: Associated pathways and factors for resistance emergence and spread.

PubMed

Alhaji, N B; Haruna, A E; Muhammad, B; Lawan, M K; Isola, T O

2018-06-01

The World Health Organization's Global Action Plan on antimicrobial resistance (AMR) recommended monitoring of antimicrobial use (AMU) through surveillance and research to help mitigate AMR. This survey was aimed at assessing poultry owners' knowledge/awareness and practices regarding AMU, identified pathways for AMR emergence and spread in small-scale commercial poultry farms and free-range local bird flocks in North-central Nigeria. An interview questionnaire-based cross-sectional study was conducted on commercial poultry farmers and local bird flock keepers in 2017. Also, a Traffic Light system model was used assess risk status of AMU in farms and flocks. All the 384 recruited poultry farmers/keepers participated in the survey. Female respondents were the majority (67.2%). Low proportion of poultry farmers (46.4%, 89/192) and very low proportion of bird keepers (6.8%, 13/192) knew antimicrobials misuse to be when administered under dose. About 48% (93/192) of farmers and 93% (179/192) of keepers arbitrary determined antimicrobial dosage before administration. Respondents used antimicrobials for therapeutic, prophylactic, and growth promotion in birds. Also, participants significantly identified contaminated poultry products, infected poultry or contaminated formites, and discharged contaminated faeces into environment as pathways for transmission of antimicrobial resistant pathogens to humans. Traffic Light system model revealed 88.5% of small-scale commercial poultry farms to frequently used antimicrobials without veterinarians' consultations thereby attaining Class 1 (Red risk) status. The model showed that 92.1% of free-range local bird flocks rarely used antimicrobials thereby attaining Class 3 (Green risk) status. Improper antimicrobial dosage in poultry (OR: 7.23; 95% CI: 2.74, 19.21), non-enforcement of AMU regulating laws in poultry (OR: 4.12; 95% CI: 2.39, 7.10), weak financial status of poultry owners (OR: 3.00; 95% CI: 2.39, 7.10), and management system (OR: 8.94; 95% CI: 5.62, 14.24) were more likely to satisfactorily influenced antimicrobials misuse in poultry farms and local bird flocks. The survey revealed low knowledge level regarding AMU in the poultry. Antimicrobials were rarely used in local bird flocks, making them likely organic and safe from AMR. It is imperative to educate farmers on judicious AMU, enforce existing veterinary legislation on antimicrobials, establish antimicrobials surveillance system, and sensitize farmers on adequate biosecurity measures and routine vaccination of farms, so as to assure food safety, food security, and public health. Copyright © 2018 Elsevier B.V. All rights reserved.

Antimicrobial Susceptibility of Campylobacter Cuniculorum Isolated from Rabbits Reared in Intensive and Rural Farms

PubMed Central

Piva, Silvia; Florio, Daniela; Mion, Domenico; Zanoni, Renato Giulio

2016-01-01

The present study aimed to investigate the antimicrobial susceptibility in Campylobacter cuniculorum. To do so, 29 isolates from rabbits reared in 18 intensive and 11 rural farms not epidemiologically correlated were tested. Minimum inhibitory concentration of 8 antimicrobial agents was determined using the agar dilution method recommended by the Clinical and Laboratory Standards Institute (Wayne, PA, USA), modified – for what supplements in the base medium and incubation conditions concern – for C. cuniculorum isolates. The isolates obtained from rural farming resulted susceptible to all the antimicrobial agents tested, with the exception of one isolate resistant to nalidixic acid. All the isolates obtained from intensively farmed rabbits were sensitive to chloramphenicol and ampicillin; 16 isolates were resistant to tetracycline; 15 to nalidixic acid and erythromycin; 13 and 10 isolates to ciprofloxacin and enrofloxacin, respectively; and only 1 to gentamicin. The resistance of several isolates to macrolides and fluoroquinolones, which are the drugs of choice in treatment of human campylobacteriosis, could pose a risk to human health if a pathogenic role of C. cuniculorum was demonstrated. PMID:27853713

Detection of antimicrobial resistance-associated proteins by titanium dioxide-facilitated intact bacteria mass spectrometry† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc04089j

PubMed Central

Zhu, Yingdi; Gasilova, Natalia; Jović, Milica; Qiao, Liang; Liu, Baohong; Lovey, Lysiane Tissières; Pick, Horst

2018-01-01

Titanium dioxide-modified target plates were developed to enhance intact bacteria analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The plates were designed to photocatalytically destroy the bacterial envelope structure and improve the ionization efficiency of intracellular components, thereby promoting the measurable mass range and the achievable detection sensitivity. Accordingly, a method for rapid detection of antimicrobial resistance-associated proteins, conferring bacterial resistance against antimicrobial drugs, was established by mass spectrometric fingerprinting of intact bacteria without the need for any sample pre-treatment. With this method, the variations in resistance proteins’ expression levels within bacteria were quickly measured from the relative peak intensities. This approach of resistance protein detection directly from intact bacteria by mass spectrometry is useful for fast discrimination of antimicrobial-resistant bacteria from their non-resistant counterparts whilst performing species identification. Also, it could be used as a rapid and convenient way for initial determination of the underlying resistance mechanisms. PMID:29719694

Validation of an UHPLC-MS/MS Method for Screening of Antimicrobial Residues in Eggs and Their Application to Analyses of Eggs from Laying Hens Subjected to Pharmacological Treatment

PubMed Central

Caldeira, Letícia Gomes Magnago; Santos, Flávio Alves; de Oliveira, Andréa Melo Garcia; Lima, Josefa Abucater; de Souza, Leonardo Francisco; da Silva, Guilherme Resende; de Assis, Débora Cristina Sampaio

2017-01-01

A multiresidue method by UHPLC/MS-MS was optimized and validated for the screening and semiquantitative detection of antimicrobials residues from tetracyclines, aminoglycosides, quinolones, lincosamides, β-lactams, sulfonamides, and macrolides families in eggs. A qualitative approach was used to ensure adequate sensitivity to detect residues at the level of interest, defined as maximum residue limit (MRL), or less. The applicability of the methods was assessed by analyzing egg samples from hens that had been subjected to pharmacological treatment with neomycin, enrofloxacin, lincomycin, oxytetracycline, and doxycycline during five days and after discontinuation of medication (10 days). The method was adequate for screening all studied analytes in eggs, since the performance parameters ensured a false-compliant rate below or equal to 5%, except for flumequine. In the analyses of eggs from laying hens subjected to pharmacological treatment, all antimicrobial residues were detected throughout the experimental period, even after discontinuation of medication, except for neomycin, demonstrating the applicability of the method for analyses of antimicrobial residues in eggs. PMID:29181222

Antimicrobial property of lemongrass (Cymbopogon citratus) oil against pathogenic bacteria isolated from pet turtles.

PubMed

De Silva, B C J; Jung, Won-Gi; Hossain, Sabrina; Wimalasena, S H M P; Pathirana, H N K S; Heo, Gang-Joon

2017-06-01

The usage of essential oils as antimicrobial agents is gaining attention. Besides, pet turtles were known to harbor a range of pathogenic bacteria while the turtle keeping is a growing trend worldwide.The current study examined the antimicrobial activity of lemon grass oil (LGO) against seven species of Gram negative bacteria namely; Aeromonas hydrophila , A. caviae , Citrobacter freundii , Salmonella enterica , Edwardsiella tarda , Pseudomonas aeruginosa , and Proteus mirabilis isolated from three popular species of pet turtles. Along with the results of disc diffusion, minimum inhibitory and minimum bactericidal concentration (MIC and MBC) tests, LGO was detected as effective against 6 species of bacteria excluding P. aeruginosa . MIC of LGO for the strains except P. aeruginosa ranged from 0.016 to 0.5% (V/V). The lowest MIC recorded in the E. tarda strain followed by A. hydrophilla , C. freundii , P. mirabilis , and S. enterica . Interestingly, all the bacterial species except E. tarda were showing high multiple antimicrobial resistance (MAR) index values ranging from 0.36 to 0.91 upon the 11 antibiotics tested although they were sensitive to LGO.

Antimicrobial property of lemongrass (Cymbopogon citratus) oil against pathogenic bacteria isolated from pet turtles

PubMed Central

De Silva, B.C.J.; Jung, Won-Gi; Hossain, Sabrina; Wimalasena, S.H.M.P.; Pathirana, H.N.K.S.

2017-01-01

The usage of essential oils as antimicrobial agents is gaining attention. Besides, pet turtles were known to harbor a range of pathogenic bacteria while the turtle keeping is a growing trend worldwide.The current study examined the antimicrobial activity of lemon grass oil (LGO) against seven species of Gram negative bacteria namely; Aeromonas hydrophila, A. caviae, Citrobacter freundii, Salmonella enterica, Edwardsiella tarda, Pseudomonas aeruginosa, and Proteus mirabilis isolated from three popular species of pet turtles. Along with the results of disc diffusion, minimum inhibitory and minimum bactericidal concentration (MIC and MBC) tests, LGO was detected as effective against 6 species of bacteria excluding P. aeruginosa. MIC of LGO for the strains except P. aeruginosa ranged from 0.016 to 0.5% (V/V). The lowest MIC recorded in the E. tarda strain followed by A. hydrophilla, C. freundii, P. mirabilis, and S. enterica. Interestingly, all the bacterial species except E. tarda were showing high multiple antimicrobial resistance (MAR) index values ranging from 0.36 to 0.91 upon the 11 antibiotics tested although they were sensitive to LGO. PMID:28747972

Analysis of microbiological screen test data for antimicrobial residues in food animals.

PubMed

Dey, B P; Thaler, Alice; Gwozdz, Frank

2003-05-01

This study analyzes the National Residue Program (NRP) of the Food Safety and Inspection Service (FSIS), United States Department of Agriculture (USDA), data for the years 1983-1998 to determine the effectiveness of all three microbiological screen tests that were developed and used by the FSIS to control antimicrobial residues in food animals. The Swab Test On Premises (STOP) was the first screen test introduced in slaughterhouses, followed by the Calf Antibiotic Sulfonamide Test (CAST) and the Fast Antimicrobial Screen Test (FAST). The data for STOP indicates that during 1983-1998, the rate of food animal carcasses with violative levels of antimicrobial residues reduced from 2.33% to 0.45% under the monitoring plan and under the surveillance plan, the rate reduced from 55.1% to 0.56%. Similarly, the data for CAST indicates that the rate of calf carcasses with violative levels of antimicrobial residue also declined significantly during those years. Because of its higher sensitivity and shorter analytical time, the use of FAST started in 1995. By 1999, it had practically replaced the use of STOP and CAST in bovine species. The use of only one test such as FAST instead of different tests has removed confusion for testing different species of food animals and thereby has enhanced the efficiency of the NRP.

Mapping Antimicrobial Stewardship in Undergraduate Medical, Dental, Pharmacy, Nursing and Veterinary Education in the United Kingdom.

PubMed

Castro-Sánchez, Enrique; Drumright, Lydia N; Gharbi, Myriam; Farrell, Susan; Holmes, Alison H

2016-01-01

To investigate the teaching of antimicrobial stewardship (AS) in undergraduate healthcare educational degree programmes in the United Kingdom (UK). Cross-sectional survey of undergraduate programmes in human and veterinary medicine, dentistry, pharmacy and nursing in the UK. The main outcome measures included prevalence of AS teaching; stewardship principles taught; estimated hours apportioned; mode of content delivery and teaching strategies; evaluation methodologies; and frequency of multidisciplinary learning. 80% (112/140) of programmes responded adequately. The majority of programmes teach AS principles (88/109, 80.7%). 'Adopting necessary infection prevention and control precautions' was the most frequently taught principle (83/88, 94.3%), followed by 'timely collection of microbiological samples for microscopy, culture and sensitivity' (73/88, 82.9%) and 'minimisation of unnecessary antimicrobial prescribing' (72/88, 81.8%). The 'use of intravenous administration only to patients who are severely ill, or unable to tolerate oral treatment' was reported in ~50% of courses. Only 32/88 (36.3%) programmes included all recommended principles. Antimicrobial stewardship principles are included in most undergraduate healthcare and veterinary degree programmes in the UK. However, future professionals responsible for using antimicrobials receive disparate education. Education may be boosted by standardisation and strengthening of less frequently discussed principles.

Prevalence and antimicrobial resistance of Enterococcus species of food animal origin from Beijing and Shandong Province, China.

PubMed

Liu, Y; Liu, K; Lai, J; Wu, C; Shen, J; Wang, Y

2013-02-01

To evaluate the prevalence and antimicrobial resistance of Enterococcus species from chickens and pigs in Beijing and Shandong Province, China. Swab samples were collected from four farms in Beijing and two in Shandong Province in 2009 and tested for Enterococcus. Minimum inhibitory concentrations of antimicrobial agents were determined using broth microdilution or agar screening methods. A total of 453 Enterococcus isolates were recovered, belonging to six different Enterococcus species. All isolates were sensitive to vancomycin. Resistance to tetracycline (92.5%), amikacin (89.4%), erythromycin (72.8%) and rifampin (58.1%), and high-level streptomycin resistance (HLSR, 50.3%) were prevalent, while resistance to penicillins (7.9% to penicillin and 4.2% to ampicillin) was rare. The resistance rates to phenicols (chloramphenicol and florfenicol) and enrofloxacin, and high-level gentamicin resistance (HLGR) were approximately 30%. The vast majority of the Enterococcus isolates were classified as multidrug-resistant organisms. Resistance of Enterococcus sp. to most antimicrobials was more prevalent in China than in European or other Asian countries. Our findings reveal a high level of antimicrobial resistance in Enterococcus isolates from food animals in China and underline the need for prudent use of antibiotics in chicken and pig production to minimize the spread of antibiotic-resistant enterococci. © 2012 The Society for Applied Microbiology.

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.

Synthesis of tritium-labeled cyadox, a promising antimicrobial growth-promoting agent with high specific activity.

PubMed

Harnud, Sechenchogt; Zhang, Aiqun; Yuan, Zonghui

2018-05-23

Cyadox is a new antimicrobial growth-promoting agent for food-producing animals. Studies on radiolabeled compounds enable the use of sensitive radiometric analytical methods and help in the elucidation of metabolic and elimination pathways. In the present study, 6-[ 3 H]-cyadox with a high specific activity of 2.08 Ci/mmol was prepared by the catalytic bromine-tritium exchange of 4-bromo-2-nitroaniline followed by a three-step microscale synthesis, giving a high yield between 36.16% and 94.75%. Copyright © 2018. Published by Elsevier Ltd.

Population structure and antimicrobial profile of Staphylococcus aureus strains associated with bovine mastitis in China.

PubMed

Zhang, Lili; Li, Yuchen; Bao, Hongduo; Wei, Ruicheng; Zhou, Yan; Zhang, Hui; Wang, Ran

2016-08-01

Staphylococcus aureus is a significant bacterial pathogen associated with bovine mastitis. The aim of the present study was to investigate and characterize of S. aureus strains isolated from the milk of cows suffering from mastitis in the mid-east of China. Among the 200 milk samples analyzed, 58 were positive for S. aureus, of these isolates, 11 isolates were methicillin-resistant Staphylococcus aureus (MRSA). All of the 58 S. aureus strains were classified in agr group I, while seven different sequence type (ST) patterns were identified and among them the most common was ST630 followed by ST188. All of the S. aureus isolates belonging to ST630 were resistant to more than four antimicrobials, and 22.2% of isolates belonging to ST188 were resistant to eight antimicrobials. Interestingly, while strong biofilm producers demonstrated higher resistance to multiple antimicrobials, they exhibited lower intracellular survival rates. The results of this study illustrated the distribution, antimicrobial susceptibility profiles, genotype, and the ability of biofilm production and mammary epithelial cells invasion of these S. aureus isolates. This study can provide the basis for the development of a disease prevention program in dairy farms to reduce the potential risk in both animal and human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

An eight-year study of Shigella species in Beijing, China: serodiversity, virulence genes, and antimicrobial resistance.

PubMed

Qu, Mei; Zhang, Xin; Liu, Guirong; Huang, Ying; Jia, Lei; Liang, Weili; Li, Xitai; Wu, Xiaona; Li, Jie; Yan, Hanqiu; Kan, Biao; Wang, Quanyi

2014-07-14

This study was conducted to determine the prevalence of serotypes, virulence factors, and antimicrobial resistance patterns of Shigella spp. in Beijing, China, from 2004 to 2011. Real-time PCR assays were used to detect virulent genes, and the Kirby-Bauer disk diffusion method was used to evaluate antimicrobial resistance. Among the total of 1,652 Shigella isolates, S. sonnei (57.1%) was the predominant species, followed by S. flexneri (42.3%), S. dysenteriae (0.4%), and S. boydii (0.2%). Nineteen serotypes were discovered among S. flexneri strains. The virulence gene ipaH was the most frequent, followed by sen and set. The presence of set showed significant difference in two dominant serogroups, S. flexneri and S. sonnei. Over 90% of Shigella isolates showed resistance to at least three drugs with widened spectrum. High-level antimicrobial resistance to single and multiple antibiotics was more common among S. sonnei than S. flexneri. There was an obvious serotype change and a dramatic increase of antibiotic resistance in Shigella prevalence in Beijing.

Biosynthesis of silver nanoparticles using Plectranthus amboinicus leaf extract and its antimicrobial activity.

PubMed

Ajitha, B; Ashok Kumar Reddy, Y; Sreedhara Reddy, P

2014-07-15

This study reports the simple green synthesis method for the preparation of silver nanoparticles (Ag NPs) using Plectranthus amboinicus leaf extract. The pathway of nanoparticles formation is by means of reduction of AgNO3 by leaf extract, which acts as both reducing and capping agents. Synthesized Ag NPs were subjected to different characterizations for studying the structural, chemical, morphological, optical and antimicrobial properties. The bright circular fringes in SAED pattern and diffraction peaks in XRD profile reveals high crystalline nature of biosynthesized Ag NPs. Morphological studies shows the formation of nearly spherical nanoparticles. FTIR spectrum confirms the existence of various functional groups of biomolecules capping the nanoparticles. UV-visible spectrum displays single SPR band at 428 nm indicating the absence of anisotropic particles. The synthesized Ag NPs exhibited better antimicrobial property towards gram negative Escherichia coli and towards tested Penicillium spp. than other tested microorganisms using disc diffusion method. Finally it has proven that the synthesized bio-inspired Ag NPs have potent antimicrobial effect. Copyright © 2014 Elsevier B.V. All rights reserved.

Application of green fluorescent protein to measure antimicrobial efficacy and the kinetics of cell death against Escherichia coli.

PubMed

Greenhalgh, Richard; Greenhalgh, Malcolm; Alshareef, Fadwa; Robson, Geoffrey D

2017-10-01

Industrial antimicrobials have been extensively used to control unwanted microbial growth by incorporation into a variety of products such as plastics and paints, reducing biodeterioration and biofouling and extending the lifespan of the product. Industrial antimicrobials generally have broad sites of action affecting core cellular functions such as central metabolism, enzyme function, cell wall or DNA synthesis and can either be biocidal or biostatic. In addition, susceptibility can be affected by the metabolic state of the microbe, with metabolically inactive cells generally more resistant than metabolically active cells. Previously it was demonstrated that cytosolically expressed green fluorescent protein could be used as a real-time viability indicator in the yeast Aureobasidium pullulans based on the pH dependent fluorescence of GFP and the collapse of the proton gradient across the cell membrane during cell death. In this study we report on the development and validation of an equivalent GFP fluorescence viability assay in Escherichia coli and used this assay to study the effect of five antimicrobials commonly used in plastics; 4,5-dichloro-2-octyl-isothiazol-3-one (DCOIT), sodium pyrithione, 1,2-benzisothiazol-3-one (BIT), 2-octyl-isothiazol-3-one (OIT) and n-butyl-1,2-benzisothiazol-3-one (BBIT). The results demonstrate broad differences amongst the antimicrobials in both relative efficacy, rate of effect and for some antimicrobials, marked differences in sensitivity toward growing and non-growing cells. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Antimicrobial resistance among invasive nontyphoidal Salmonella enterica isolates in the United States: National Antimicrobial Resistance Monitoring System, 1996 to 2007.

PubMed

Crump, John A; Medalla, Felicita M; Joyce, Kevin W; Krueger, Amy L; Hoekstra, R Michael; Whichard, Jean M; Barzilay, Ezra J

2011-03-01

Nontyphoidal salmonellae (NTS) are important causes of community-acquired bloodstream infection. We describe patterns of antimicrobial resistance among invasive NTS in the United States. We compared bloodstream NTS isolates with those from stool submitted to the National Antimicrobial Resistance Monitoring System (NARMS) from 1996 to 2007. We describe antimicrobial resistance among invasive strains by serogroup and serotype. Of the 19,302 NTS isolates, 17,804 (92.2%) were from stool or blood. Of these, 1,050 (5.9%) were bloodstream isolates. The median ages (ranges) of patients with and without bacteremia were 36 (<1 to 97) years and 20 (<1 to 105) years, respectively (P < 0.001). Males (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.06 to 1.38) and those ≥65 years of age were at greater risk for invasive disease. Salmonella enterica serotypes Enteritidis, Typhimurium, and Heidelberg were the most common serotypes isolated from blood; S. enterica serotypes Dublin, Sandiego, and Schwarzengrund were associated with the greatest risk for bloodstream isolation. Of invasive isolates, 208 (19.8%) were resistant to ampicillin, 117 (11.1%) to chloramphenicol, and 26 (2.5%) to trimethoprim-sulfamethoxazole; 28 (2.7%) isolates were resistant to nalidixic acid and 26 (2.5%) to ceftriaxone. Antimicrobial resistance to traditional agents is common. However, the occurrence of nalidixic acid and ceftriaxone resistance among invasive NTS is cause for clinical and public health vigilance.

Antimicrobial Resistance among Invasive Nontyphoidal Salmonella enterica Isolates in the United States: National Antimicrobial Resistance Monitoring System, 1996 to 2007 ▿

PubMed Central

Crump, John A.; Medalla, Felicita M.; Joyce, Kevin W.; Krueger, Amy L.; Hoekstra, R. Michael; Whichard, Jean M.; Barzilay, Ezra J.

2011-01-01

Nontyphoidal salmonellae (NTS) are important causes of community-acquired bloodstream infection. We describe patterns of antimicrobial resistance among invasive NTS in the United States. We compared bloodstream NTS isolates with those from stool submitted to the National Antimicrobial Resistance Monitoring System (NARMS) from 1996 to 2007. We describe antimicrobial resistance among invasive strains by serogroup and serotype. Of the 19,302 NTS isolates, 17,804 (92.2%) were from stool or blood. Of these, 1,050 (5.9%) were bloodstream isolates. The median ages (ranges) of patients with and without bacteremia were 36 (<1 to 97) years and 20 (<1 to 105) years, respectively (P < 0.001). Males (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.06 to 1.38) and those ≥65 years of age were at greater risk for invasive disease. Salmonella enterica serotypes Enteritidis, Typhimurium, and Heidelberg were the most common serotypes isolated from blood; S. enterica serotypes Dublin, Sandiego, and Schwarzengrund were associated with the greatest risk for bloodstream isolation. Of invasive isolates, 208 (19.8%) were resistant to ampicillin, 117 (11.1%) to chloramphenicol, and 26 (2.5%) to trimethoprim-sulfamethoxazole; 28 (2.7%) isolates were resistant to nalidixic acid and 26 (2.5%) to ceftriaxone. Antimicrobial resistance to traditional agents is common. However, the occurrence of nalidixic acid and ceftriaxone resistance among invasive NTS is cause for clinical and public health vigilance. PMID:21199924

Cloacael Carriage and Multidrug Resistance Escherichia coli O157:H7 from Poultry Farms, Eastern Ethiopia

PubMed Central

Shecho, Mude; Muktar, Yimer

2017-01-01

A cross-sectional study was carried out to determine antimicrobial drug resistance patterns of E. coli O157:H7 isolates and estimate the level of the pathogen. A total of 194 cloacae swab samples were collected randomly in two poultry farms. Standard cultural, biochemical, and serological (latex agglutination) methods were used to isolate E. coli O157:H7. The isolates were subjected to antimicrobial susceptibility testing using disc diffusion method. Out of 194 cloacae samples examined, 13.4% (n = 26) were found to be positive for E. coli O157:H7. The finding indicated differences in E. coli O157:H7 infection among the different risk factors. Chicken from Adele Poultry Farm showed higher E. coli O157:H7 infection (OR = 3.89) than Haramaya University poultry farm and young birds had more infection (OR = 4.62) than adult birds. Of the total 14 antimicrobials included in the panel of study, the susceptibility results were varied with 96.15% and 0% E. coli O157:H7 isolates expressing resistance to erythromycin, clindamycin, spectinomycin, and ciprofloxacin, respectively. Multidrug resistance to more than two antimicrobial agents was detected in 24 (92.30%) of the isolates. The study showed high presence of antimicrobial resistant isolates of E. coli O157:H7. Further study is required to better understand the ecology and evolution of bacterial resistance to antimicrobial agents. PMID:28349121

Cloacael Carriage and Multidrug Resistance Escherichia coli O157:H7 from Poultry Farms, Eastern Ethiopia.

PubMed

Shecho, Mude; Thomas, Naod; Kemal, Jelalu; Muktar, Yimer

2017-01-01

A cross-sectional study was carried out to determine antimicrobial drug resistance patterns of E. coli O157:H7 isolates and estimate the level of the pathogen. A total of 194 cloacae swab samples were collected randomly in two poultry farms. Standard cultural, biochemical, and serological (latex agglutination) methods were used to isolate E. coli O157:H7. The isolates were subjected to antimicrobial susceptibility testing using disc diffusion method. Out of 194 cloacae samples examined, 13.4% ( n = 26) were found to be positive for E. coli O157:H7. The finding indicated differences in E. coli O157:H7 infection among the different risk factors. Chicken from Adele Poultry Farm showed higher E. coli O157:H7 infection (OR = 3.89) than Haramaya University poultry farm and young birds had more infection (OR = 4.62) than adult birds. Of the total 14 antimicrobials included in the panel of study, the susceptibility results were varied with 96.15% and 0% E. coli O157:H7 isolates expressing resistance to erythromycin, clindamycin, spectinomycin, and ciprofloxacin, respectively. Multidrug resistance to more than two antimicrobial agents was detected in 24 (92.30%) of the isolates. The study showed high presence of antimicrobial resistant isolates of E. coli O157:H7. Further study is required to better understand the ecology and evolution of bacterial resistance to antimicrobial agents.

Prevalence and Antimicrobial Resistance of Salmonella Isolates from Chicken Carcasses in Retail Markets in Yangon, Myanmar.

PubMed

Moe, Aung Zaw; Paulsen, Peter; Pichpol, Duangporn; Fries, Reinhard; Irsigler, Herlinde; Baumann, Maximilian P O; Oo, Kyaw Naing

2017-06-01

A cross-sectional investigation was conducted concerning prevalence, antimicrobial resistance, multidrug resistance patterns, and serovar diversity of Salmonella in chicken meat sold at retail in Yangon, Myanmar. The 141 chicken meat samples were collected at 141 retail markets in the Yangon Region, Myanmar, 1 November 2014 to 31 March 2015. Information on hygienic practices (potential risk factors) was retrieved via checklists. Salmonella was isolated and identified according to International Organization for Standardization methods (ISO 6579:2002) with minor modifications. Twelve antimicrobial agents belonging to eight pharmacological groups were used for antimicrobial susceptibility testing (disk diffusion method). Salmonella was recovered from 138 (97.9%) of the 141 samples. The isolates were most frequently resistant to trimethoprim-sulfamethoxazole (70.3% of isolates), tetracycline (54.3%), streptomycin (49.3%), and ampicillin (47.1%). Resistance was also found to chloramphenicol (29.7%), amoxicillin-clavulanic acid (17.4%), ciprofloxacin (9.4%), tobramycin (8.7%), gentamicin (8%), cefazolin (7.2%), lincomycin-spectinomycin (5.8%), and norfloxacin (0.7%). Among the 138 Salmonella isolates, 72 (52.2%) were resistant to three or more antimicrobial agents. Twenty-four serovars were identified among the 138 Salmonella-positive samples; serovars Albany, Kentucky, Braenderup, and Indiana were found in 38, 11, 10, and 8% of samples, respectively. None of the potential risk factors were significantly related to Salmonella contamination of chicken carcasses. This study provides new information regarding prevalence and antimicrobial resistance and Salmonella serovar diversity in retail markets in Yangon, Myanmar.

SCC mec typing and antimicrobial resistance of methicillin-resistant Staphylococcus aureus (MRSA) from pigs of Northeast India.

PubMed

Rajkhowa, S; Sarma, D K; Pegu, S R

2016-12-01

Staphylococcus aureus is one of the most important pathogens of both humans and animal. Methicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen that causes serious infections both in hospitals and communities due to its multidrug resistance tendency. This study was undertaken to characterize the MRSA isolates from pigs and to determine the antimicrobial resistance of these isolates. Forty nine MRSA strains (one strain per positive pig) isolated from pigs of Northeast India were characterized by SCCmec typing and antimicrobial resistance. The overall prevalence of MRSA was 7.02 % with the highest prevalence recorded in pigs aged 1-3 months (P = 0.001) and in nasal samples (P = 0.005). Two SCC mec types (type III and V) were found in Indian pigs with predominance of type V. All isolates were resistant to penicillin. Seventeen resistance groups were observed where 87.75 % isolates showed multidrug resistance (showed resistance to three or more classes of antimicrobials). The most predominant resistance pattern observed was Oxytetracycline + Penicillin + Sulfadiazine + Tetracycline accounting 12.24 % of the isolates. The present study contributes to the understanding of characteristics and antimicrobial resistance of porcine MRSA isolates which in turn will help in devising strategy for the control of this pathogen. Findings of the study also throw light on multidrug resistance MRSA and emphasize the need for judicious use of antimicrobials in animal practice.

Antimicrobial resistance in zoonotic nontyphoidal Salmonella: an alarming trend?

PubMed

Michael, G B; Schwarz, S

2016-12-01

Zoonotic bacteria of the genus Salmonella have acquired various antimicrobial resistance properties over the years. The corresponding resistance genes are commonly located on plasmids, transposons, gene cassettes, or variants of the Salmonella Genomic Islands SGI1 and SGI2. Human infections by nontyphoidal Salmonella isolates mainly result from ingestion of contaminated food. The two predominantly found Salmonella enterica subsp. enterica serovars in the USA and in Europe are S. Enteritidis and S. Typhimurium. Many other nontyphoidal Salmonella serovars have been implicated in foodborne Salmonella outbreaks. Summary reports of the antimicrobial susceptibility patterns of nontyphoidal Salmonella isolates over time suggest a moderate to low level of antimicrobial resistance and multidrug-resistance. However, serovar-specific analyses showed in part a steady state, a continuous decline, or a recent increase in resistance to certain antimicrobial agents. Resistance to critically important antimicrobial agents, e.g. third-generation cephalosporins and (fluoro)quinolones is part of many monitoring programmes and the corresponding results confirm that extended-spectrum β-lactamases are still rarely found in nontyphoidal Salmonella serovars, whereas resistance to (fluoro)quinolones is prevalent at variable frequencies among different serovars from humans and animals in different countries. Although it is likely that nontyphoidal Salmonella isolates from animals represent a reservoir for resistance determinants, it is mostly unknown where and when Salmonella isolates acquired resistance properties and which exchange processes have happened since then. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Microbiological characterization and probiotic potential of koko and koko sour water, African spontaneously fermented millet porridge and drink.

PubMed

Lei, V; Jakobsen, M

2004-01-01

To identify and examine the diversity of predominant lactic acid bacteria (LAB) in koko and koko sour water (KSW) from different Ghanaian production sites with regard to pattern of fermentation (API 50 CHL), genotype, antimicrobial activity, and resistance to low pH and bile salts. In total 215 LAB were isolated from koko and KSW. The isolates were identified using intergenic transcribed spacers (ITS)-PCR restriction fragment length polymorphism (RFLP), API 50 CHL, restriction enzyme analysis with pulsed-field gel electrophoresis (REA-PFGE) and sequencing of the 16S rRNA gene. The dominating micro-organisms in koko was found to be Weisella confusa and Lactobacillus fermentum, followed by Lact. salivarius and Pediococcus spp. Chemometric data analysis were used to link the LAB species to the different production stages and production sites. At intra-species level the isolates were found to have a great diversity. The isolates were investigated for antimicrobial activity using agar diffusion assays, and acid and bile tolerance. Most isolates showed low levels of antimicrobial activity towards the indicator strain Listeria innocua, but not towards the bacteriocin-sensitive Lact. sakei. Growth of all LAB isolates was unaffected by the presence of 0.3% (v/v) oxgall bile. The isolates were able to survive, but were not able to grow in growth medium adjusted to pH 2.5. The dominating LAB of koko and KSW were W. confusa and Lact. fermentum showing a pronounced taxonomic biodiversity at sub-species level between stages within the production as well as between production sites. Other species observed in KSW were Lact. salivarius, Ped. pentosaceus, Ped. acidilactici and Lact. paraplantarum. They occurred in levels of 108 CFU ml-1 in fresh KSW and showed uniform antimicrobial activity, and acid and bile tolerance. The present study gives a detailed picture of the taxonomy and diversity of LAB in an African-fermented millet product that may have potential as a probiotic product for the local population. The chemometric tools Principal Component Analysis and anova Partial Least Squares Regression were proven to be useful in the analysis of microbial groupings and associations with specific sites and stages in the production of koko and KSW.

[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.

2012 European guideline on the diagnosis and treatment of gonorrhoea in adults.

PubMed

Bignell, C; Unemo, M

2013-02-01

Gonorrhoea is a major public health concern globally. Of particularly grave concern is that resistance to the extended-spectrum cephalosporins has emerged during the most recent years. This guideline provides recommendations regarding the diagnosis and treatment of gonorrhoea in Europe. Compared to the outdated 2009 European gonorrhoea guideline, this 2012 European gonorrhoea guideline provides up-to-date guidance on, broader indications for testing and treatment of gonorrhoea;the introduction of dual antimicrobial therapy (ceftriaxone 500 mg and azithromycin 2 g) for uncomplicated gonorrhoea when the antimicrobial sensitivity is unknown; recommendation of test of cure in all gonorrhoea cases to ensure eradication of infection and identify emerging resistance; and recommendations to identify, verify and report failures with recommended treatment regimens. Optimisations of the testing, diagnostics, antimicrobial treatment and follow-up of gonorrhoea patients are crucial in controlling the emergent spread of cephalosporin-resistant and multidrug-resistant gonorrhoea.

Nisin as a Food Preservative: Part 2: Antimicrobial Polymer Materials Containing Nisin.

PubMed

Gharsallaoui, Adem; Joly, Catherine; Oulahal, Nadia; Degraeve, Pascal

2016-06-10

Nisin is the only bacteriocin approved as a food preservative because of its antibacterial effectiveness and its negligible toxicity for humans. Typical problems encountered when nisin is directly added to foods are mainly fat adsorption leading to activity loss, heterogeneous distribution in the food matrix, inactivation by proteolytic enzymes, and emergence of resistance in normally sensitive bacteria strains. To overcome these problems, nisin can be immobilized in solid matrices that must act as diffusional barriers and allow controlling its release rate. This strategy allows maintaining a just sufficient nisin concentration at the food surface. The design of such antimicrobial materials must consider both bacterial growth kinetics but also nisin release kinetics. In this review, nisin incorporation in polymer-based materials will be discussed and special emphasis will be on the applications and properties of antimicrobial food packaging containing this bacteriocin.

Myrcia ovata Cambessedes essential oils: A proposal for a novel natural antimicrobial against foodborne bacteria.

PubMed

de Jesus, Isabela Cristina; Santos Frazão, Gladslene Góes; Blank, Arie Fitzgerald; de Aquino Santana, Luciana Cristina Lins

2016-10-01

This paper reports the innovative antibacterial activity of essential oils (EOs) from nine Myrcia ovata Cambessedes plants against eight foodborne bacteria. Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Enterococcus faecalis and Pseudomonas aeruginosa were the most susceptible bacteria to EOs. In particular, the P. aeruginosa, which is usually resistant to antimicrobials agents, was extremely sensitive to some EOs. The gram-positive and gram-negative bacteria were inhibited and eliminated with minimum EOs concentrations ranging from 0.78 to 25 μL/mL. The Serratia marcensces and Escherichia coli were less susceptible to EOs alone. Consequently, some EOs combinations were investigated by checkerboard method against these bacteria and a synergistic effect was obtained. Myrcia ovata Cambessedes EOs showed high inhibitory and bactericidal effects against foodborne bacteria might be an interesting alternative for future applications as natural antimicrobials in food systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of white mustard essential oil on the growth of foodborne pathogens and spoilage microorganisms and the effect of food components on its efficacy.

PubMed

Monu, Emefa A; David, Jairus R D; Schmidt, Marcel; Davidson, P Michael

2014-12-01

Antimicrobial preservative compounds are added to foods to target specific pathogens and spoilage organisms. White mustard essential oil (WMEO) is an extract that contains 4-hydroxybenzyl isothiocyanate, a compound which has been demonstrated to have antimicrobial activity in limited studies. The objective of this research was to determine the in vitro antimicrobial activity of WMEO against gram-positive and gram-negative spoilage and pathogenic bacteria and determine the effect of food components on the antimicrobial activity. The bacteria Escherichia coli, Salmonella enterica serovar Enteritidis, Enterobacter aerogenes, Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, and Lactobacillus fermentum, as well as the acid- and preservative-resistant yeast Schizosaccharomyces pombe, were evaluated. All microorganisms were inhibited by WMEO at 8.3 g/liter (equivalent to 1,000 mg/liter 4-hydroxybenzyl isothiocyanate). In general, WMEO was more effective against gram-negative than against gram-positive bacteria. Salmonella Enteritidis and S. pombe were the most sensitive, with inhibition at as low as 2.1 g/liter. The effects on growth profiles varied but included increased lag phases and lethality, indicating both bacteriostatic and bactericidal activity. Soybean oil had a negative effect on the efficacy of WMEO against L. monocytogenes, and at 5% soybean oil, the antimicrobial activity against Salmonella Enteritidis was eliminated after 48 h. Sodium caseinate at 1% also negated the antimicrobial effect of WMEO against Salmonella Enteritidis and decreased its effectiveness against L. monocytogenes. The presence of starch had no significant effect on the antimicrobial activity of WMEO against L. monocytogenes and Salmonella Enteritidis. Thus, WMEO is effective against a wide range of microorganisms and has potential to be used in foods, depending upon the target microorganism and food components present.

Duplex DNA-Invading γ-Modified Peptide Nucleic Acids Enable Rapid Identification of Bloodstream Infections in Whole Blood.

PubMed

Nölling, Jörk; Rapireddy, Srinivas; Amburg, Joel I; Crawford, Elizabeth M; Prakash, Ranjit A; Rabson, Arthur R; Tang, Yi-Wei; Singer, Alon

2016-04-19

Bloodstream infections are a leading cause of morbidity and mortality. Early and targeted antimicrobial intervention is lifesaving, yet current diagnostic approaches fail to provide actionable information within a clinically viable time frame due to their reliance on blood culturing. Here, we present a novel pathogen identification (PID) platform that features the use of duplex DNA-invading γ-modified peptide nucleic acids (γPNAs) for the rapid identification of bacterial and fungal pathogens directly from blood, without culturing. The PID platform provides species-level information in under 2.5 hours while reaching single-CFU-per-milliliter sensitivity across the entire 21-pathogen panel. The clinical utility of the PID platform was demonstrated through assessment of 61 clinical specimens, which showed >95% sensitivity and >90% overall correlation to blood culture findings. This rapid γPNA-based platform promises to improve patient care by enabling the administration of a targeted first-line antimicrobial intervention. Bloodstream infections continue to be a major cause of death for hospitalized patients, despite significant improvements in both the availability of treatment options as well their application. Since early and targeted antimicrobial intervention is one of the prime determinants of patient outcome, the rapid identification of the pathogen can be lifesaving. Unfortunately, current diagnostic approaches for identifying these infections all rely on time-consuming blood culture, which precludes immediate intervention with a targeted antimicrobial. To address this, we have developed and characterized a new and comprehensive methodology, from patient specimen to result, for the rapid identification of both bacterial and fungal pathogens without the need for culturing. We anticipate broad interest in our work, given the novelty of our technical approach combined with an immense unmet need. Copyright © 2016 Nölling et al.

Kinetics activity of Yersinia Intermedia Against ZnO Nanoparticles Either Synergism Antibiotics by Double-Disc Synergy Test Method.

PubMed

Fathi Azar Khavarani, Motahareh; Najafi, Mahla; Shakibapour, Zahra; Zaeifi, Davood

2016-03-01

Bacterial resistance to the commonly used antibacterial agents is an increasing challenge in the medicine, and a major problem for the health care systems; the control of their spread is a constant challenge for the hospitals. In this study, we have investigated the antimicrobial activity of the Zinc Oxide nanoparticles against clinical sample; Yersinia intermedia bacteria. Nanoparticle susceptibility constants and death kinetic were used to evaluate the antimicrobial characteristics of the Zinc Oxide (ZnO) against the bacteria. Antimicrobial tests were performed with 10 8 cfu.mL -1 at baseline. At first, Minimum Inhibitory Concentration (MIC) of ZnO was determined and then nanoparticle suspension at one and two times of the MIC was used for death kinetic and susceptibility constant assay at 0 to 360 min treatment time. ZnO nanoparticles with size ranging from 10 to 30 nm showed the highest susceptibility reaction against Y. intermedia (Z=39.06 mL.μg -1 ). The process of Y. intermedia death in ZnO suspension was assumed to follow the first-order kinetics and the survival ratio of bacteria decreased with the increasing treatment time. An increased concentration of the nanoparticle was seen to enhance the bactericidal action of the nanoparticle. Then we performed the best ratio of the nanoparticles on semi-sensitive and resistance antibiotic for the bacteria. However, based on experimental results, synergy of ZnO nanoparticles and Oxacilin was determined and Y. intermedia showed a higher sensitivity compared to the ZnO nanoparticles alone. The results of the present study illustrates that ZnO has a strong antimicrobial effect and could potentially be employed to aid the bacterial control. It could also improve- antibacterial effects in combination with the antibiotics.

[Neisseria gonorrhoeae: antimicrobial resistance and study of population dynamics. Situation in Barcelona in 2011].

PubMed

Serra-Pladevall, Judit; Barberá-Gracia, María Jesús; Roig-Carbajosa, Glòria; Juvé-Saumell, Rosa; Gonzalez-Lopez, Juan José; Bartolomé-Comas, Rosa; Andreu-Domingo, Antònia

2013-11-01

Due to the high rates of antimicrobial resistance to certain antibiotics, together with the emergence of Neisseria gonorrhoeae (NG) with reduced susceptibility and resistance to third-generation cephalosporins, gonococcal infection is becoming a public health problem. The objectives of the study were: To keep track of the antimicrobial susceptibility of NG strains obtained from January to August 2011. To study the population dynamics. The antimicrobial susceptibility was studied by disk-diffusion and E-test. The genotyping was performed by NG-MAST method. Of a total of 100strains studied, 59% showed intermediate sensitivity to penicillin and 9% were resistant. According to EUCAST, we detected 3gonococci with reduced susceptibility to ceftriaxone, 10 to cefixime and one with high-level resistance to both antibiotics (MIC 1.5μg/ml). MIC50 and MIC90 to cefixime were 0.016 and 0.125μg/ml, respectively, whereas to ceftriaxone they were <0.016 and 0.064μg/ml, respectively. Almost all (99%) of the strains were resistant to doxycycline, 53% to ciprofloxacin, 3% to azithromycin, and 1% to spectinomycin. The most prevalent ST was ST1407, predominantly associated to resistance or reduced sensitivity to cephalosporins or macrolides. NG has developed significant rates of resistance to various antibiotics. One strain has been detected with high level resistance to third generation cephalosporins, and several strains with reduced susceptibility. An increase in MIC50 and MIC90 to these antibiotics has also been observed. NG population structure remains stable and common to the rest of Europe, although two new ST (ST7226 and ST7227) have been identified that could be selected and acquire high levels of resistance to cephalosporins. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Changing Patterns in Enteric Fever Incidence and Increasing Antibiotic Resistance of Enteric Fever Isolates in the United States, 2008–2012

PubMed Central

Date, Kashmira A.; Newton, Anna E.; Medalla, Felicita; Blackstock, Anna; Richardson, LaTonia; McCullough, Andre; Mintz, Eric D.; Mahon, Barbara E.

2016-01-01

Background Enteric fever in the United States has been primarily associated with travel and with worrisome changes in global patterns of antimicrobial resistance. We present the first comprehensive report of National Typhoid and Paratyphoid Fever Surveillance System (NTPFS) data for a 5-year period (2008–2012). Methods We reviewed data on laboratory-confirmed cases reported to NTPFS, and related antimicrobial susceptibility results of Salmonella Typhi and Paratyphi A isolates sent for testing by participating public health laboratories to the Centers for Disease Control and Prevention’s National Antimicrobial Resistance Monitoring System laboratory. Results During 2008–2012, 2341 enteric fever cases were reported, 80% typhoid and 20% paratyphoid A. The proportion caused by paratyphoid A increased from 16% (2008) to 22% (2012). Foreign travel within 30 days preceding illness onset was reported by 1961 (86%) patients (86% typhoid and 92% paratyphoid A). Travel to southern Asia was common (82% for typhoid, 97% for paratyphoid A). Among 1091 (58%) typhoid and 262 (56%) paratyphoid A isolates tested for antimicrobial susceptibility, the proportion resistant to nalidixic acid (NAL-R) increased from 2008 to 2012 (Typhi, 60% to 68%; Paratyphi A, 91% to 94%). Almost all NAL-R isolates were resistant or showed decreased susceptibility to ciprofloxacin. Resistance to at least ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole (multidrug resistant [MDR]) was limited to Typhi isolates, primarily acquired in southern Asia (13%). Most MDR isolates were also NAL-R. Conclusions Enteric fever in the United States is primarily associated with travel to southern Asia, and increasing resistance is adding to treatment challenges. A bivalent typhoid and paratyphoid vaccine is needed. PMID:27090993

Evidence for moxifloxacin in community-acquired pneumonia: the impact of pharmaco-economic considerations on guidelines.

PubMed

Simoens, Steven

2009-10-01

In an era of limited resources, policy makers and health care payers are concerned about the costs of treatment in addition to its effectiveness. However, guidelines do not tend to consider the cost-effectiveness of treatment options. This paper aims to conduct an international literature review with a view to assessing the impact of pharmaco-economic considerations of CAP treatment with moxifloxacin on recent guidelines. The pharmaco-economic state of the art of treating CAP with moxifloxacin is assessed and compared with guidelines issued by the European Respiratory Society and by the Infectious Diseases Society of America/American Thoracic Society. Also, evidence on moxifloxacin consumption and antimicrobial resistance, and the impact of resistance on the cost-effectiveness of moxifloxacin is reviewed. Studies were identified by searching PubMed, Centre for Reviews and Dissemination databases, Cochrane Database of Systematic Reviews, and EconLit up to January 2009. The existing pharmaco-economic evidence indicates that moxifloxacin is a cost-effective treatment for CAP. However, data limitations and uncertainty surrounding the evolution of resistance emphasize the need for caution. As recommended by guidelines, the choice of antimicrobial should consider the local frequency of causative pathogens, the local pattern of antimicrobial resistance, and risk factors for resistant bacteria. The pharmaco-economic evidence corroborates the importance of these factors as they have an impact on the cost-effectiveness of treating CAP patients with moxifloxacin. CAP guidelines need to take into account pharmaco-economic considerations by balancing the effectiveness of antimicrobial regimens against their costs. The pharmaco-economic value of moxifloxacin is influenced by the causative pathogens involved and resistance patterns. Therefore, it may be advisable to identify patient subgroups in which treatment with moxifloxacin is cost-effective and should be recommended by guidelines.

Antibiotic resistance and biofilm formation among coagulase-negative staphylococci isolated from clinical samples at a tertiary care hospital of eastern Nepal.

PubMed

Shrestha, Lok Bahadur; Bhattarai, Narayan Raj; Khanal, Basudha

2017-01-01

Coagulase negative staphylococci were long regarded non-pathogenic as they are the commensals of human skin and mucosa but the recent changes in the medical practice and changes in underlying host populations, they are being considered significant pathogens associated with number of nosocomial infections. The objective of the study was to determine the species, antimicrobial susceptibility pattern, biofilm forming ability of the clinically significant CoNS isolates and to compare the different methods for the detection of biofilm formation. A total of 52 clinically significant CoNS isolates obtained from different units during a year period were studied. Characterization was done using standard microbiological guidelines and antimicrobial susceptibility was done following CLSI guidelines. Biofilm formation was detected by using three methods i.e. tissue culture plate method, congo red agar method and tube adherence method. Among 52 isolates , S. epidermidis (52%) was the most common species which was followed by S. saprophyticus (18%) and S. haemolyticus (14%). Antimicrobial susceptibility pattern of CoNS documented resistance of 80% to ampicillin. Resistance to cefoxitin and ceftriaxone was observed in 58% of the isolates. Biofilm formation was observed in 65.38% of the isolates. The accuracy of Congo red agar and tube adherence method for the detection of biofilm formation was 82% and 76% respectively. CoNS isolates obtained from clinical samples should be processed routinely and antimicrobial susceptibility testing should be performed. Multidrug-resistant CoNS are prevalent. All the three methods i.e. tissue culture plate, Congo red agar and tube adherence method can be used in detecting biofilm formation.

Changing Patterns in Enteric Fever Incidence and Increasing Antibiotic Resistance of Enteric Fever Isolates in the United States, 2008-2012.

PubMed

Date, Kashmira A; Newton, Anna E; Medalla, Felicita; Blackstock, Anna; Richardson, LaTonia; McCullough, Andre; Mintz, Eric D; Mahon, Barbara E

2016-08-01

Enteric fever in the United States has been primarily associated with travel and with worrisome changes in global patterns of antimicrobial resistance. We present the first comprehensive report of National Typhoid and Paratyphoid Fever Surveillance System (NTPFS) data for a 5-year period (2008-2012). We reviewed data on laboratory-confirmed cases reported to NTPFS, and related antimicrobial susceptibility results of Salmonella Typhi and Paratyphi A isolates sent for testing by participating public health laboratories to the Centers for Disease Control and Prevention's National Antimicrobial Resistance Monitoring System laboratory. During 2008-2012, 2341 enteric fever cases were reported, 80% typhoid and 20% paratyphoid A. The proportion caused by paratyphoid A increased from 16% (2008) to 22% (2012). Foreign travel within 30 days preceding illness onset was reported by 1961 (86%) patients (86% typhoid and 92% paratyphoid A). Travel to southern Asia was common (82% for typhoid, 97% for paratyphoid A). Among 1091 (58%) typhoid and 262 (56%) paratyphoid A isolates tested for antimicrobial susceptibility, the proportion resistant to nalidixic acid (NAL-R) increased from 2008 to 2012 (Typhi, 60% to 68%; Paratyphi A, 91% to 94%). Almost all NAL-R isolates were resistant or showed decreased susceptibility to ciprofloxacin. Resistance to at least ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole (multidrug resistant [MDR]) was limited to Typhi isolates, primarily acquired in southern Asia (13%). Most MDR isolates were also NAL-R. Enteric fever in the United States is primarily associated with travel to southern Asia, and increasing resistance is adding to treatment challenges. A bivalent typhoid and paratyphoid vaccine is needed. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Phenotypic and genotypic antimicrobial susceptibility pattern of Streptococcus spp. isolated from cases of clinical mastitis in dairy cattle in Poland.

PubMed

Kaczorek, E; Małaczewska, J; Wójcik, R; Rękawek, W; Siwicki, A K

2017-08-01

Mastitis of dairy cattle is one of the most frequently diagnosed diseases worldwide. The main etiological agents of mastitis are bacteria of the genus Streptococcus spp., in which several antibiotic resistance mechanisms have been identified. However, detailed studies addressing this problem have not been conducted in northeastern Poland. Therefore, the aim of our study was to analyze, on phenotypic and genotypic levels, the antibiotic resistance pattern of Streptococcus spp. isolated from clinical cases of mastitis from dairy cattle in this region of Poland. The research was conducted using 135 strains of Streptococcus (Streptococcus uberis, n = 53; Streptococcus dysgalactiae, n = 41; Streptococcus agalactiae, n = 27; other streptococci, n = 14). The investigation of the antimicrobial susceptibility to 8 active substances applied in therapy in the analyzed region, as well as a selected bacteriocin (nisin), was performed using the minimum inhibitory concentration method. The presence of selected resistance genes (n = 14) was determined via PCR. We also investigated the correlation between the presence of resistance genes and the antimicrobial susceptibility of the examined strains in vitro. The highest observed resistance of Streptococcus spp. was toward gentamicin, kanamycin, and tetracycline, whereas the highest susceptibility occurred toward penicillin, enrofloxacin, and marbofloxacin. Additionally, the tested bacteriocin showed high efficacy. The presence of 13 analyzed resistance genes was observed in the examined strains [gene mef(A) was not detected]. In most strains, at least one resistance gene, mainly responsible for resistance to tetracyclines [tet(M), tet(K), tet(L)], was observed. However, a relationship between the presence of a given resistance gene and antimicrobial susceptibility on the phenotypic level was not always observed. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Antimicrobial-Resistant Pathogens Associated With Healthcare-Associated Infections: Summary of Data Reported to the National Healthcare Safety Network at the Centers for Disease Control and Prevention, 2011-2014.

PubMed

Weiner, Lindsey M; Webb, Amy K; Limbago, Brandi; Dudeck, Margaret A; Patel, Jean; Kallen, Alexander J; Edwards, Jonathan R; Sievert, Dawn M

2016-11-01

OBJECTIVE To describe antimicrobial resistance patterns for healthcare-associated infections (HAIs) that occurred in 2011-2014 and were reported to the Centers for Disease Control and Prevention's National Healthcare Safety Network. METHODS Data from central line-associated bloodstream infections, catheter-associated urinary tract infections, ventilator-associated pneumonias, and surgical site infections were analyzed. These HAIs were reported from acute care hospitals, long-term acute care hospitals, and inpatient rehabilitation facilities. Pooled mean proportions of pathogens that tested resistant (or nonsusceptible) to selected antimicrobials were calculated by year and HAI type. RESULTS Overall, 4,515 hospitals reported that at least 1 HAI occurred in 2011-2014. There were 408,151 pathogens from 365,490 HAIs reported to the National Healthcare Safety Network, most of which were reported from acute care hospitals with greater than 200 beds. Fifteen pathogen groups accounted for 87% of reported pathogens; the most common included Escherichia coli (15%), Staphylococcus aureus (12%), Klebsiella species (8%), and coagulase-negative staphylococci (8%). In general, the proportion of isolates with common resistance phenotypes was higher among device-associated HAIs compared with surgical site infections. Although the percent resistance for most phenotypes was similar to earlier reports, an increase in the magnitude of the resistance percentages among E. coli pathogens was noted, especially related to fluoroquinolone resistance. CONCLUSION This report represents a national summary of antimicrobial resistance among select HAIs and phenotypes. The distribution of frequent pathogens and some resistance patterns appear to have changed from 2009-2010, highlighting the need for continual, careful monitoring of these data across the spectrum of HAI types. Infect Control Hosp Epidemiol 2016;1-14.

Isolation and characterization of Treponema phagedenis-like spirochetes from digital dermatitis lesions in Swedish dairy cattle.

PubMed

Pringle, Märit; Bergsten, Christer; Fernström, Lise-Lotte; Höök, Helena; Johansson, Karl-Erik

2008-10-20

Digital dermatitis in cattle is an emerging infectious disease. Ulcerative lesions are typically located on the plantar skin between the heel bulbs and adjacent to the coronet. Spirochetes of the genus Treponema are found in high numbers in the lesions and are likely to be involved in the pathogenesis. The aim of this study was to obtain pure cultures of spirochetes from cattle with digital dermatitis and to describe them further. Tissue samples and swabs from active digital dermatitis lesions were used for culturing. Pure isolates were subjected to, molecular typing through 16S rRNA gene sequencing, pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD) and an intergenic spacer PCR developed for Treponema spp. as well as API-ZYM and antimicrobial susceptibility tests. The antimicrobial agents used were tiamulin, valnemulin, tylosin, aivlosin, lincomycin and doxycycline. Seven spirochete isolates from five herds were obtained. Both 16S rRNA gene sequences, which were identical except for three polymorphic nucleotide positions, and the intergenic spacer PCR indicated that all isolates were of one yet unnamed species, most closely related to Treponema phagedenis. The enzymatic profile and antimicrobial susceptibility pattern were also similar for all isolates. However it was possible to separate the isolates through their PFGE and RAPD banding pattern. This is the first report on isolation of a Treponema sp. from cattle with digital dermatitis in Scandinavia. The phylotype isolated has previously been cultured from samples from cattle in the USA and the UK and is closely related to T. phagedenis. While very similar, the isolates in this study were possible to differentiate through PFGE and RAPD indicating that these methods are suitable for subtyping of this phylotype. No antimicrobial resistance could be detected among the tested isolates.

Susceptibility to antimicrobials of mastitis-causing Staphylococcus aureus, Streptococcus uberis and Str. dysgalactiae from New Zealand and the USA as assessed by the disk diffusion test.

PubMed

Petrovski, K R; Grinberg, A; Williamson, N B; Abdalla, M E; Lopez-Villalobos, N; Parkinson, T J; Tucker, I G; Rapnicki, P

2015-07-01

To compare the antimicrobial susceptibility patterns of three common mastitis pathogens (Staphylococcus aureus, Streptococcus uberis and Str. dysgalactiae) isolated from milk samples from New Zealand and the USA. A total of 182 S. aureus, 126 Str. uberis and 89 Str. dysgalactiae isolates from New Zealand (107, 106 and 41, respectively) and the USA (75, 20 and 48, respectively) were assessed using the disk diffusion test. Susceptibility varied among the bacterial species. All isolates were susceptible to the amoxicillin-clavulanic acid combination. Resistance to lincomycin was most frequent (susceptibility of 8.6%) across all species. Non-susceptible (i.e. resistant or intermediate) isolates of S. aureus were identified for the three non-isoxazolyl penicillins (amoxicillin, ampicillin and penicillin: 20.6% and 36.0%) and lincomycin (99.9% and 94.6%) for NZ and the USA, respectively. Resistance to erythromycin (5.3%) and tetracyclines (6.7%) was detected only in isolates from the USA. There were differences in susceptibility between Str. uberis and Str. dysgalactiae; all streptococcal isolates demonstrated resistance to aminoglycosides (neomycin 52.4% and streptomycin 27.9%) and enrofloxacin (28%). Resistance of Str. dysgalactiae to tetracycline was almost 100.0% and to oxytetracycline 89.9%. Most of the isolates tested were susceptible to most of the antimicrobials commonly used for treatment of bovine mastitis, with the exception of the lincosamides. Susceptibility to a selected class-representative antimicrobial and at the genus level should be interpreted with caution. Differences between NZ and the USA confirm the value of national surveys to determine the susceptibility patterns of mastitis pathogens. © 2015 Australian Veterinary Association.

Burden of methicillin-resistant Staphylococcus aureus pneumonia among hospitalized patients in Lebanon and Saudi Arabia.

PubMed

Althaqafi, Abdulhakeem O; Matar, Madonna J; Moghnieh, Rima; Alothman, Adel F; Alenazi, Thamer H; Farahat, Fayssal; Corman, Shelby; Solem, Caitlyn T; Raghubir, Nirvana; Macahilig, Cynthia; Haider, Seema; Stephens, Jennifer M

2017-01-01

The objective of this study is to describe the real-world treatment patterns and burden of suspected or confirmed methicillin-resistant Staphylococcus aureus (MRSA) pneumonia in Saudi Arabia and Lebanon. A retrospective chart review study evaluated 2011-2012 data from hospitals in Saudi Arabia and Lebanon. Patients were included if they had been discharged with a diagnosis of MRSA pneumonia, which was culture proven or suspected based on clinical criteria. Hospital data were abstracted for a random sample of patients to capture demographics (eg, age and comorbidities), treatment patterns (eg, timing and use of antimicrobials), hospital resource utilization (eg, length of stay), and clinical outcomes (eg, clinical status at discharge and mortality). Descriptive results were reported using frequencies or proportions for categorical variables and mean and standard deviation for continuous variables. Chart-level data were collected for 93 patients with MRSA pneumonia, 50 in Saudi Arabia and 43 in Lebanon. The average age of the patients was 56 years, and 60% were male. The most common comorbidities were diabetes (39%), congestive heart failure (30%), coronary artery disease (29%), and chronic obstructive pulmonary disease (28%). Patients most frequently had positive cultures from pulmonary (87%) and blood (27%) samples. All isolates were sensitive to vancomycin, teicoplanin, and linezolid, and only one-third of the isolates tested were sensitive to ciprofloxacin. Beta-lactams (inactive therapy for MRSA) were prescribed 21% of the time across all lines of therapy, with 42% of patients receiving first-line beta-lactams. Fifteen percent of patients did not receive any antibiotics that were considered to be MRSA active. The mean hospital length of stay was 32 days, and in-hospital mortality was 30%. The treatment for MRSA pneumonia in Saudi Arabia and Lebanon may be suboptimal with inactive therapy prescribed a substantial proportion of the time. The information gathered from this Middle East sample provides important perspectives on the current treatment patterns.

In vitro investigation of antimicrobial activities of ethnomedicinal plants against dental caries pathogens.

PubMed

Besra, Mamta; Kumar, Vipin

2018-05-01

The study aimed to evaluate the antimicrobial activity of medicinal plant extracts against the bacterial pathogens prominent in dental caries. A total of 20 plant species (herbs, shrubs and trees) belonging to 18 genera and 15 families were documented for dental caries. Antimicrobial activity of solvent extracts and essential oil from plants were determined by zone of inhibition on the growth of Streptococcus mutans (MTCC 497) and Lactobacillus acidophilus (MTCC 10307) using the agar well diffusion method. The results of in vitro antimicrobial assay prove that methanol is more successful in the extraction of phytochemicals from plant samples than aqueous solvent, as methanol extracts show higher antimicrobial activity than aqueous extracts against both the test pathogens. Methanol extracts of Nigella sativa, Psidium guajava and Syzygium aromaticum were the most effective among all 20 plant samples and have potent inhibitory activity against both dental caries pathogens with minimum inhibitory concentration of 0.2 mg mL - 1 . N. sativa seed methanol extract was more effective with 22.3 mm zone of inhibition at 0.2 mg mL - 1 against S. mutans (MTCC 497), while L. acidophilus (MTCC 10307) was more sensitive to S. aromaticum bud methanol extract at 11.3 mm zone of inhibition at concentration 0.1 mg mL - 1 . Essential oil extracted from plants also possesses strong antimicrobial activity for both test pathogens, with a minimum inhibitory concentration range of 0.05-0.16 mg mL - 1 . Syzygium aromaticum bud essential oil at 0.05 mg mL - 1 was most active against S. mutans (MTCC 497). Plant extracts viewing antimicrobial activity with minimum inhibitory concentration show the efficacy of the plant products that could be considered as a good indicator of prospective plants for discovering new antimicrobial agents against dental caries pathogens. The findings of this study provide a lead to further polyherbal formulations for the treatment of dental caries malaise.

Functional toxicogenomic assessment of triclosan in human ...

EPA Pesticide Factsheets

Thousands of chemicals for which limited toxicological data are available are used and then detected in humans and the environment. Rapid and cost-effective approaches for assessing the toxicological properties of chemicals are needed. We used CRISPR-Cas9 functional genomic screening to identify potential molecular mechanism of a widely used antimicrobial triclosan (TCS) in HepG2 cells. Resistant genes (whose knockout gives potential resistance) at IC50 (50% Inhibition concentration of cell viability) were significantly enriched in adherens junction pathway, MAPK signaling pathway and PPAR signaling pathway, suggesting a potential molecular mechanism in TCS induced cytotoxicity. Evaluation of top-ranked resistant genes, FTO (encoding an mRNA demethylase) and MAP2K3 (a MAP kinase kinase family gene), revealed that their loss conferred resistance to TCS. In contrast, sensitive genes (whose knockout enhances potential sensitivity) at IC10 and IC20 were specifically enriched in pathways involved with immune responses, which was concordant with the transcriptomic profiling of TCS at concentrations

Microencapsulated antimicrobial compounds as a means to enhance electron beam irradiation treatment for inactivation of pathogens on fresh spinach leaves.

PubMed

Gomes, Carmen; Moreira, Rosana G; Castell-Perez, Elena

2011-08-01

Recent outbreaks associated to the consumption of raw or minimally processed vegetable products that have resulted in several illnesses and a few deaths call for urgent actions aimed at improving the safety of those products. Electron beam irradiation can extend shelf-life and assure safety of fresh produce. However, undesirable effects on the organoleptic quality at doses required to achieve pathogen inactivation limit irradiation. Ways to increase pathogen radiation sensitivity could reduce the dose required for a certain level of microbial kill. The objective of this study was to evaluate the effectiveness of using natural antimicrobials when irradiating fresh produce. The minimum inhibitory concentration of 5 natural compounds and extracts (trans-cinnamaldehyde, eugenol, garlic extract, propolis extract, and lysozyme with ethylenediaminetetraacetate acid (disodium salt dihydrate) was determined against Salmonella spp. and Listeria spp. In order to mask odor and off-flavor inherent of several compounds, and to increase their solubility, complexes of these compounds and extracts with β-cyclodextrin were prepared by the freeze-drying method. All compounds showed bacteriostatic effect at different levels for both bacteria. The effectiveness of the microencapsulated compounds was tested by spraying them on the surface of baby spinach inoculated with Salmonella spp. The dose (D₁₀ value) required to reduce the bacterial population by 1 log was 0.190 kGy without antimicrobial addition. The increase in radiation sensitivity (up to 40%) varied with the antimicrobial compound. These results confirm that the combination of spraying microencapsulated antimicrobials with electron beam irradiation was effective in increasing the killing effect of irradiation. Foodborne illness outbreaks attributed to fresh produce consumption have increased and present new challenges to food safety. Current technologies (water washing or treating with 200 ppm chlorine) cannot eliminate internalized pathogens. Ionizing radiation is a viable alternative for eliminating pathogens; however, the dose required to inactivate these pathogens is often too high to be tolerated by the fresh produce without undesirable quality changes. This study uses natural antimicrobial ingredients as radiosensitizers. These ingredients were encapsulated and applied to fresh produce that was subsequently irradiated. The process results in high level of microorganism inactivation using lower doses than the conventional irradiation treatments. © 2011 Institute of Food Technologists®

Causative Organisms and Associated Antimicrobial Resistance in Healthcare-Associated, Central Line-Associated Bloodstream Infections From Oncology Settings, 2009-2012.

PubMed

See, Isaac; Freifeld, Alison G; Magill, Shelley S

2016-05-15

Recent antimicrobial resistance data are lacking from inpatient oncology settings to guide infection prophylaxis and treatment recommendations. We describe central line-associated bloodstream infection (CLABSI) pathogens and antimicrobial resistance patterns reported from oncology locations to the Centers for Disease Control and Prevention's National Healthcare Safety Network (NHSN). CLABSI data reported to NHSN from 2009 to 2012 from adult inpatient oncology locations were compared to data from nononcology adult locations within the same hospitals. Pathogen profile, antimicrobial resistance rates, and CLABSI incidence rates per 1000 central line-days were calculated. CLABSI incidence rates were compared using Poisson regression. During 2009-2012, 4654 CLABSIs were reported to NHSN from 299 adult oncology units. The most common organisms causing CLABSI in oncology locations were coagulase-negative staphylococci (16.9%), Escherichia coli (11.8%), and Enterococcus faecium (11.4%). Fluoroquinolone resistance was more common among E. coli CLABSI in oncology than nononcology locations (56.5% vs 41.5% of isolates tested; P < .0001) and increased significantly from 2009-2010 to 2011-2012 (49.5% vs 60.4%; P = .01). Furthermore, rates of CLABSI were significantly higher in oncology compared to nononcology locations for fluoroquinolone-resistant E. coli (rate ratio, 7.37; 95% confidence interval [CI], 6.20-8.76) and vancomycin-resistant E. faecium (rate ratio, 2.27, 95% CI, 2.03-2.53). However, resistance rates for some organisms, such as Klebsiella species and Pseudomonas aeruginosa, were lower in oncology than in nononcology locations. Antimicrobial-resistant E. coli and E. faecium have become significant pathogens in oncology. Practices for antimicrobial prophylaxis and empiric antimicrobial therapy should be regularly assessed in conjunction with contemporary antimicrobial resistance data. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Streptococcus pneumoniae non-susceptibility and outpatient antimicrobial prescribing rates at the Alaska Native Medical Center

PubMed Central

Stevens, Ryan W.; Wenger, Jay; Bulkow, Lisa; Bruce, Michael G.

2013-01-01

Background American Indian/Alaska Native (AI/AN) people suffer substantially higher rates of invasive pneumococcal disease (IPD) than the general US population. We evaluated antimicrobial prescribing data and their association with non-susceptibility in Streptococcus pneumoniae causing IPD in AI/AN people between 1992 and 2009. Methods Antimicrobial use data were gathered from the electronic patient management system and included all prescriptions dispensed to Alaska Native patients aged 5 years and older from outpatient pharmacies at the Alaska Native Medical Center (ANMC). Antimicrobial susceptibility data were gathered from pneumococcal isolates causing IPD among Anchorage Service Unit AI/AN residents aged 5 years and older. Data were restricted to serotypes not contained in the pneumococcal vaccine (PCV7). Results Over the study period, overall antimicrobial prescribing increased 59% (285/1,000 persons/year in 1992 to 454/1,000 persons per year in 2009, p<0.001). Trimethoprim/sulfamethoxazole prescribing increased (43/1,000 persons/year in 1992 to 108/1,000 persons/year in 2009, p<0.001) and non-susceptibility to trimethoprim/sulfamethoxazole in AI/AN patients ≥5 years of age increased in non-PCV7 serotypes (0–12%, p<0.05). Similarly, prescribing rates increased for macrolide antibiotics (46/1,000 persons/year in 1992 to 84/1,000 persons/year in 2009, p<0.05). We observed no statistically significant change over time in erythromycin non-susceptibility among non-PCV7 serotypes in AI/AN patients aged 5 years or greater (0–7%, p=0.087). Conclusion Antimicrobial prescribing patterns of some antibiotics in the AI/AN population corresponded to increased antimicrobial resistance in clinical isolates. This study highlights the on-going threat of antimicrobial resistance, the critical importance of judicious prescribing of antibiotics and the potential utility of prescribing data for addressing this issue. PMID:24358456

Antimicrobial susceptibility profiles of gram-negative bacteria causing infections collected across India during 2014-2016: Study for monitoring antimicrobial resistance trend report.

PubMed

Veeraraghavan, Balaji; Jesudason, Mark Ranjan; Prakasah, John Antony Jude; Anandan, Shalini; Sahni, Rani Diana; Pragasam, Agila Kumari; Bakthavatchalam, Yamuna Devi; Selvakumar, Rajesh Joseph; Dhole, T N; Rodrigues, Camilla; Roy, Indranil; Joshi, Sangeetha; Chaudhuri, Bhaskar Narayan; Chitnis, D S

2018-01-01

The emergence of antibiotic resistance among bacterial pathogens in the hospital and community has increased the concern to the health-care providers due to the limited treatment options. Surveillance of antimicrobial resistance (AMR) in frequently isolated bacterial pathogens causing severe infections is of great importance. The data generated will be useful for the clinicians to decide empiric therapy on the local epidemiological resistance profile of the antimicrobial agents. This study aims to monitor the distribution of bacterial pathogen and their susceptibility pattern to the commonly used antimicrobial agents. This study includes Gram-negative bacilli collected from intra-abdominal, urinary tract and respiratory tract infections during 2014-2016. Isolates were collected from seven hospitals across India. All the study isolates were characterised up to species level, and minimum inhibitory concentration was determined for a wide range of antimicrobials included in the study panel. The test results were interpreted as per standard Clinical Laboratory Standards Institute guidelines. A total of 2731 isolates of gram-negative bacteria were tested during study period. The most frequently isolated pathogens were 44% of Escherichia coli (n = 1205) followed by 25% of Klebsiella pneumoniae (n = 676) and 11% of Pseudomonas aeruginosa (n = 308). Among the antimicrobials tested, carbapenems were the most active, followed by amikacin and piperacillin/tazobactam. The rate of extended-spectrum beta-lactamase (ESBL)-positive isolates were ranged from 66%-77% in E. coli to 61%-72% in K. pneumoniae, respectively. Overall, colistin retains its activity in > 90% of the isolates tested and appear promising. Increasing rates of ESBL producers have been noted, which is alarming. Further, carbapenem resistance was also gradually increasing, which needs much attention. Overall, this study data show that carbapenems, amikacin and colistin continue to be the best agents available to treat drug-resistant infections. Thus continuous monitoring of susceptibility profile of the clinically important Gram-negative pathogens is of great importance to guide effective antimicrobial therapy.

Costs and length of stay associated with antimicrobial resistance in acute kidney injury patients with bloodstream infection.

PubMed

Vandijck, D M; Blot, S I; Decruyenaere, J M; Vanholder, R C; De Waele, J J; Lameire, N H; Claus, S; De Schuijmer, J; Dhondt, A W; Verschraegen, G; Hoste, E A

2008-01-01

Antimicrobial resistance negatively impacts on prognosis. Intensive care unit (ICU) patients, and particularly those with acute kidney injury (AKI), are at high risk for developing nosocomial bloodstream infections (BSI) due to multi-drug-resistant strains. Economic implications in terms of costs and length of stay (LOS) attributable to antimicrobial resistance are underevaluated. This study aimed to assess whether microbial susceptibility patterns affect costs and LOS in a well-defined cohort of ICU patients with AKI undergoing renal replacement therapy (RRT) who developed nosocomial BSI. Historical study (1995-2004) enrolling all adult RRT-dependent ICU patients with AKI and nosocomial BSI. Costs were considered as invoiced in the Belgian reimbursement system, and LOS was used as a surrogate marker for hospital resource allocation. Of the 1330 patients with AKI undergoing RRT, 92 had microbiologic evidence of nosocomial BSI (57/92, 62% due to a multi-drug-resistant microorganism). Main patient characteristics were equal in both groups. As compared to patients with antimicro-4 bial-susceptible BSI, patients with antimicrobial-resistant BSI were more likely to acquire Gram-positive infection (72.6% vs 25.5%, P<0.001). No differences were found neither in LOS (ICU before BSI, ICU, hospital before BSI, hospital, hospital after BSI, and time on RRT; all P>0.05) or hospital costs (all P>0.05) when comparing patients with antimicrobial-resistant vs antimicrobial-susceptible BSI. However, although not statistically significant, patients with BSI caused by resistant Gram-negative-, Candida-, or anaerobic bacteria incurred substantial higher costs than those without. In a cohort of ICU patients with AKI and nosocomial BSI undergoing RRT, patients with antimicrobial-resistant vs antimicrobial-susceptible Gram-positive BSI did not have longer hospital stays, or higher hospital costs. Patients with resistant "other" (i.e. Gram-negative, Candida, or anaerobic) BSI were found to have a distinct trend towards increased resources use as compared to patients with susceptible "other" BSI, respectively.

Changes in the equine fecal microbiota associated with the use of systemic antimicrobial drugs.

PubMed

Costa, Marcio C; Stämpfli, Henry R; Arroyo, Luis G; Allen-Vercoe, Emma; Gomes, Roberta G; Weese, J Scott

2015-02-03

The intestinal tract is a rich and complex environment and its microbiota has been shown to have an important role in health and disease in the host. Several factors can cause disruption of the normal intestinal microbiota, including antimicrobial therapy, which is an important cause of diarrhea in horses. This study aimed to characterize changes in the fecal bacterial populations of healthy horses associated with the administration of frequently used antimicrobial drugs. Twenty-four adult mares were assigned to receive procaine penicillin intramuscularly (IM), ceftiofur sodium IM, trimethoprim sulfadiazine (TMS) orally or to a control group. Treatment was given for 5 consecutive days and fecal samples were collected before drug administration (Day 1), at the end of treatment (Days 5), and on Days 14 and 30 of the trial. High throughput sequencing of the V4 region of the 16S rRNA gene was performed using an Illumina MiSeq sequencer. Significant changes of population structure and community membership were observed after the use of all drugs. TMS caused the most marked changes on fecal microbiota even at higher taxonomic levels including a significant decrease of richness and diversity. Those changes were mainly due to a drastic decrease of Verrucomicrobia, specifically the "5 genus incertae sedis". Changes in structure and membership caused by antimicrobial administration were specific for each drug and may be predictable. Twenty-five days after the end of treatment, bacterial profiles were more similar to pre-treatment patterns indicating a recovery from changes caused by antimicrobial administration, but differences were still evident, especially regarding community membership. The use of systemic antimicrobials leads to changes in the intestinal microbiota, with different and specific responses to different antimicrobials. All antimicrobials tested here had some impact on the microbiota, but TMS significantly reduced bacterial species richness and diversity and had the greatest apparent impact on population structure, specifically targeting members of the Verrucomicrobia phylum.

[Oxacillin-resistant coagulase-negative Staphylococci bacteremia at a teaching hospital in Santa Maria, State of Rio Grande do Sul, Brazil].

PubMed

Rigatti, Fabiane; Tizotti, Maísa Kraulich; Hörner, Rosmari; Domingues, Vanessa Oliveira; Martini, Rosiéli; Mayer, Letícia Eichstaedt; Khun, Fábio Teixeira; de França, Chirles Araújo; da Costa, Mateus Matiuzzi

2010-01-01

This study aimed to characterize the prevalence and susceptibility profile to oxacillin-resistant Coagulase-negative Staphylococci strains isolated from blood cultures in a teaching hospital, located in Santa Maria, RS. In addition, different methodologies for phenotypic characterization of mecA-mediated oxacillin resistance were compared with genotypic reference testing. After identification (MicroScan - Siemens), the isolates were tested for antimicrobial sensitivity using disk diffusion and automation (MicroScan - Siemens). The presence of mecA gene was identified by the polymerase chain reaction molecular technique. The most common species was Staphylococcus epidermidis (n=40, 67%). The mecA gene was detected in 54 (90%) strains, while analysis of the sensitivity profiles revealed a high rate of resistance to multiple classes of antimicrobial drugs. However, all isolates were uniformly sensitive to vancomycin and tigecycline. The cefoxitin disk was the phenotypic method that best correlated with the gold standard. Analysis of the clinical significance of CoNS isolated from hemocultures and the precise detection of oxacillin resistance represent decisive factors for the correct choice of antibiotic therapy. Although vancomycin constitutes the normal treatment in most Brazilian hospitals, reduction in its use is recommended.

Antibiotic use and resistance in emerging economies: a situation analysis for Viet Nam

PubMed Central

2013-01-01

Background 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. Methods 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. Results 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. Conclusions 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. PMID:24325208

Evaluation of the effectiveness of different brands' disks in antimicrobial disk susceptibility tests.

PubMed

Lam, C P; Tsai, W C

1989-08-01

A total of 813 routine isolates of aerobic and facultatively anaerobic bacteria were employed to determine the efficacy of different branded (Oxoid, Difco, BBL) antimicrobial disks, using disk antimicrobial susceptibility tests, for a total of 22 kinds of antimicrobial disks and 10,740 antibiotic-organism comparisons. Major positive and major negative discrepancies in results were defined as a change from "susceptible" to "both resistant", and a change from "resistant" to "both susceptible" according to the National Committee for Clinical Laboratory Standards' interpretive standards for zone diameters. Minor positive and minor negative discrepancies were defined as a change from "susceptible" to "both intermediate", or "intermediate" to "both resistant"; and a change from "resistant" to "both intermediate", or "intermediate" to "both susceptible". The overall agreements of Oxoid, Difco, and BBL systems were 98%, 98.7%, and 98.4% respectively, and their differences are not statistically significant. Different kinds of antimicrobial disks' representative patterns of these three brands are further analyzed: (A) In the Oxoid series, there were 220 discrepancies. Minor negative discrepancy is predominant, most frequently related to carbenicillin (25), gentamicin (13) and cephalothin (10). Besides minor negative discrepancy, carbenicillin also had six minor positive discrepancies. Tetracyclin had ten minor positive discrepancies. (B) In the Difco series, there were 137 discrepancies. The majority of them are minor positive discrepancies. Moxalactam (11) and cefotaxime (10) are the most common antibiotics involved. (C) In the BBL series, there were 170 discrepancies. Minor positive discrepancy was the predominant one, which mostly related to carbenicillin (24), amikacin (13), and ceftizoxime (12). In addition, tetracyclin had 24 times minor negative discrepancies. Laboratory workers must pay attention to these different patterns of representation. In order to evaluate the quality of 11 pairs of the give-away and the purchased BBL disks, we also compared the results for these 813 routine isolates (a total of 5,482 antibiotic-organism comparisons). The giveaway disks demonstrated 99.1% overall agreement with the purchased disks. There were 48 minor discrepancies [26 (0.47%) minor positive discrepancies and 22 (0.4%) minor negative discrepancies]. These results allow this study to emphasize the followings in order to raise the awareness of the laboratory workers: (i) alteration of disk efficacy during transportation and storage; (ii) major considerations in choosing different brands' antimicrobial disks, and (iii) the important roles played by salespersons and pharmaceutical companies in achieving sound results.