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

PubMed

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

2018-06-22

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

Epidemiology of antibiotic and heavy metal resistance in bacteria: resistance patterns in staphylococci isolated from populations in Iraq exposed and not exposed to heavy metals or antibiotics

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

Groves, D.J.; Short, H.; Thewaini, A.J.

Staphylococci were isolated from rural and urban populations in Iraq, which were not known to be exposed to either heavy metals or antibiotics. The antibiotic and heavy metal resistance patterns of these strains were analyzed in both mannitol-fermenting and nonfermenting strains. Over 90% of the strains were resistant to at least one of the following antibiotics: penicillin, chloramphenicol, erythromycin, tetracycline, cephalothin, lincomycin, and methicillin. In general, mannitol-fermenting strains were resistant to penicillin and cupric ions. Mannitol-negative strains were more frequently associated with mercuric ion and tetracycline resistance. Although resistance to penicillin and tetracycline can coexist, the combination of penicillin resistancemore » and tetracycline resistance usually occurred in mannitol-negative strains. The possibility of selection of heavy metal-resistant strains due to exposure to toxic levels of methylmercury was examined. No significant increase in mercuric ion-resistant strains of staphylococci or Escherichia coli were detected in exposed populations as compared to control groups. The possible reasons for this result are discussed.« less

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.

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

PubMed

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

2014-05-01

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

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

PubMed

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

2016-03-01

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

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.

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.

Antibiotic resistance rates and physician antibiotic prescription patterns of uncomplicated urinary tract infections in southern Chinese primary care

PubMed Central

Kung, Kenny; Au-Doung, Philip Lung Wai; Ip, Margaret; Lee, Nelson; Fung, Alice; Wong, Samuel Yeung Shan

2017-01-01

Uncomplicated urinary tract infections (UTI) are common in primary care. Whilst primary care physicians are called to be antimicrobial stewards, there is limited primary care antibiotic resistance surveillance and physician antibiotic prescription data available in southern Chinese primary care. The study aimed to investigate the antibiotic resistance rate and antibiotic prescription patterns in female patients with uncomplicated UTI. Factors associated with antibiotic resistance and prescription was explored. A prospective cohort study was conducted in 12 primary care group clinics in Hong Kong of patients presenting with symptoms of uncomplicated UTI from January 2012 to December 2013. Patients’ characteristics such as age, comorbidity, presenting symptoms and prior antibiotic use were recorded by physicians, as well as any empirical antibiotic prescription given at presentation. Urine samples were collected to test for antibiotic resistance of uropathogens. Univariate analysis was conducted to identify factors associated with antibiotic resistance and prescription. A total of 298 patients were included in the study. E. coli was detected in 107 (76%) out of the 141 positive urine samples. Antibiotic resistance rates of E. coli isolates for ampicillin, co-trimoxazole, ciprofloxacin, amoxicillin and nitrofurantoin were 59.8%, 31.8%, 23.4%, 1.9% and 0.9% respectively. E. coli isolates were sensitive to nitrofurantoin (98.1%) followed by amoxicillin (78.5%). The overall physician antibiotic prescription rate was 82.2%. Amoxicillin (39.6%) and nitrofurantoin (28.6%) were the most common prescribed antibiotics. Meanwhile, whilst physicians in public primary care prescribed more amoxicillin (OR: 2.84, 95% CI: 1.67 to 4.85, P<0.001) and nitrofurantoin (OR: 2.01, 95% CI: 1.14 to 3.55, P = 0.015), physicians in private clinics prescribed more cefuroxime and ciprofloxacin (P<0.05). Matching of antibiotic prescription and antibiotic sensitivity of E. coli isolates occurred in public than private primary care prescriptions (OR: 6.72, 95% CI: 2.07 to 21.80 P = 0.001) and for other uropathogens (OR: 6.19, 95% CI: 1.04 to 36.78 P = 0.034). Mismatching differences of antibiotic prescription and resistance were not evident. In conclusion, nitrofurantoin and amoxicillin should be used as first line antibiotic treatment for uncomplicated UTI. There were significant differences in antibiotic prescription patterns between public and private primary care. Public primary care practitioners were more likely to prescribe first line antibiotic treatment which match antibiotic sensitivity of E. coli isolates and other uropathogens. Further exploration of physician prescribing behaviour and educational interventions, particularly in private primary care may helpful. Meanwhile, development and dissemination of guidelines for primary care management of uncomplicated UTI as well as continued surveillance of antibiotic resistance and physician antibiotic prescription is recommended. PMID:28486532

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

PubMed

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

2015-01-01

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

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

PubMed

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

2017-03-01

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

The sludge loading rate regulates the growth and release of heterotrophic bacteria resistant to six types of antibiotics in wastewater activated sludge.

PubMed

Yuan, Qing-Bin; Guo, Mei-Ting; Yang, Jian

2015-01-01

Wastewater treatment plants are considered as hot reservoirs of antimicrobial resistance. However, the fates of antibiotic-resistant bacteria during biological treatment processes and relevant influencing factors have not been fully understood. This study evaluated the effects of the sludge loading rate on the growth and release of six kinds of antibiotic-resistant bacteria in an activated sludge system. The results indicated that higher sludge loading rates amplified the growth of all six types of antibiotic resistant bacteria. The release of most antibiotic-resistant bacteria through both the effluent and biosolids was amplified with increased sludge loading rate. Biosolids were the main pattern for all antibiotic-resistant bacteria release in an activated sludge system, which was determined primarily by their growth in the activated sludge. A higher sludge loading rate reactor tended to retain more antibiotic resistance. An activated sludge system with lower sludge loading rates was considered more conducive to the control of antibiotic resistance.

Antibiotic resistance profile of bacterial isolates from animal farming aquatic environments and meats in a peri-urban community in Daejeon, Korea.

PubMed

Rho, Hyunjin; Shin, Bongjin; Lee, Okbok; Choi, Yu-Hyun; Rho, Jaerang; Lee, Jiyoung

2012-05-01

The increasing usage of antibiotics in the animal farming industry is an emerging worldwide problem contributing to the development of antibiotic resistance. The purpose of this work was to investigate the prevalence and antibiotic resistance profile of bacterial isolates collected from animal farming aquatic environments and meats in a peri-urban community in Daejeon, Korea. In an antibacterial susceptibility test, the bacterial isolates showed a high incidence of resistance (∼26.04%) to cefazolin, tetracycline, gentamycin, norfloxacin, erythromycin and vancomycin. The results from a test for multiple antibiotic resistance indicated that the isolates were displaying an approximately 5-fold increase in the incidence of multiple antibiotic resistance to combinations of two different antibiotics compared to combinations of three or more antibiotics. Most of the isolates showed multi-antibiotic resistance, and the resistance patterns were similar among the sampling groups. Sequencing data analysis of 16S rRNA showed that most of the resistant isolates appeared to be dominated by the classes Betaproteobacteria and Gammaproteobacteria, including the genera Delftia, Burkholderia, Escherichia, Enterobacter, Acinetobacter, Shigella and Pseudomonas.

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

PubMed

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

2016-01-01

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

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

PubMed Central

Trojan, Rugira; Razdan, Lovely

2016-01-01

We determined the prevalence and antibiotic susceptibilities patterns of bacterial isolates from pus samples collected from patients in a tertiary care hospital of Punjab, India. E. coli was the most prevalent pathogen (51.2%) followed by Staphylococcus aureus (21%), Klebsiella pneumoniae (11.6%), Pseudomonas aeruginosa (5.8%), Citrobacter spp. (3.5%), Acinetobacter baumannii (2.3%), Proteus mirabilis (2.3%), and Streptococcus spp. (2.3%). E. coli, K. pneumoniae, A. baumannii, and Citrobacter isolates were resistant to multiple antibiotics including higher generation cephalosporins. S. aureus and Streptococcus isolates were sensitive to cloxacillin and vancomycin. However, P. aeruginosa, P. mirabilis, and Streptococcus isolates were found to be less resistant to the spectrum of antibiotics tested. Overall, our findings indicate the prevalence of resistance to different classes of antibiotics in bacterial isolates from pus infections and hence highlight the need for effective surveillance, regulator reporting, and antibiogram-guided antibiotic prescription. PMID:27872643

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

PubMed

Trojan, Rugira; Razdan, Lovely; Singh, Nasib

2016-01-01

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

Functional and Molecular Surveillance of Helicobacter pylori Antibiotic Resistance in Kuala Lumpur

PubMed Central

Teh, Xinsheng; Khosravi, Yalda; Lee, Woon Ching; Leow, Alex Hwong Ruey; Loke, Mun Fai; Vadivelu, Jamuna; Goh, Khean Lee

2014-01-01

Background Helicobacter pylori is the etiological agent for diseases ranging from chronic gastritis and peptic ulcer disease to gastric adenocarcinoma and primary gastric B-cell lymphoma. Emergence of resistance to antibiotics possesses a challenge to the effort to eradicate H. pylori using conventional antibiotic-based therapies. The molecular mechanisms that contribute to the resistance of these strains have yet to be identified and are important for understanding the evolutional pattern and selective pressure imposed by the environment. Methods and Findings H. pylori was isolated from 102 patients diagnosed with gastrointestinal diseases, who underwent endoscopy at University Malaya Medical Centre (UMMC). The isolates were tested for their susceptibility on eleven antibiotics using Etest. Based on susceptibility test, 32.3% of the isolates were found to have primary metronidazole resistance; followed by clarithromycin (6.8%) and fluoroquinolones (6.8%). To further investigate the resistant strains, mutational patterns of gene rdxA, frxA, gyrA, gyrB, and 23S rRNA were studied. Consistent with the previous reports, metronidazole resistance was prevalent in the local population. However, clarithromycin, fluoroquinolone and multi-drug resistance were shown to be emerging. Molecular patterns correlated well with phenotypic data. Interestingly, multi-drug resistant (MDR) strains were found to be associated with higher minimum inhibitory concentration (MIC) than their single-drug resistant (SDR) counterparts. Most importantly, clarithromycin-resistant strains were suggested to have a higher incidence for developing multi-drug resistance. Conclusion Data from this study highlighted the urgency to monitor closely the prevalence of antibiotic resistance in the Malaysian population; especially that of clarithromycin and multi-drug resistance. Further study is needed to understand the molecular association between clarithromycin resistance and multi-drug resistance in H. pylori. The report serves a reminder that a strict antibiotic usage policy is needed in Malaysia and other developing countries (especially those where H. pylori prevalence remained high). PMID:25003707

Antibiotic-Impregnated Central Venous Catheters Do Not Change Antibiotic Resistance Patterns.

PubMed

Turnbull, Isaiah R; Buckman, Sara A; Horn, Christopher B; Bochicchio, Grant V; Mazuski, John E

2018-01-01

Antibiotic-impregnated central venous catheters (CVCs) decrease the incidence of infection in high-risk patients. However, use of these catheters carries the hypothetical risk of inducing antibiotic resistance. We hypothesized that routine use of minocycline and rifampin-impregnated catheters (MR-CVC) in a single intensive care unit (ICU) would change the resistance profile for Staphylococcus aureus. We reviewed antibiotic susceptibilities of S. aureus isolates obtained from blood cultures in a large urban teaching hospital from 2002-2015. Resistance patterns were compared before and after implementation of MR-CVC use in the surgical ICU (SICU) in August 2006. We also compared resistance patterns of S. aureus obtained in other ICUs and in non-ICU patients, in whom MR-CVCs were not used. Data for rifampin, oxacillin, and clindamycin were available for 9,703 cultures; tetracycline resistance data were available for 4,627 cultures. After implementation of MR-CVC use in the SICU, rifampin resistance remained unchanged, with rates the same as in other ICU and non-ICU populations (3%). After six years of use of MR-CVCs in the SICU, the rate of tetracycline resistance was unchanged in all facilities (1%-3%). The use of MR-CVCs was not associated with any change in S. aureus oxacillin-resistance rates in the SICU (66% vs. 60%). However, there was a significant decrease in S. aureus clindamycin resistance (59% vs. 34%; p < 0.05) in SICU patients. Routine use of rifampin-minocycline-impregnated CVCs in the SICU was not associated with increased resistance of S. aureus isolates to rifampin or tetracyclines.

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 ...

The path of least resistance in oral surgery.

PubMed

Fee, Laura

2016-01-01

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

Phylogenetic group distributions, virulence factors and antimicrobial resistance properties of uropathogenic Escherichia coli strains isolated from patients with urinary tract infections in South Korea.

PubMed

Lee, J H; Subhadra, B; Son, Y-J; Kim, D H; Park, H S; Kim, J M; Koo, S H; Oh, M H; Kim, H-J; Choi, C H

2016-01-01

Urinary tract infections (UTIs) are one of the most common diseases by which humans seek medical help and are caused mainly by uropathogenic Escherichia coli (UPEC). Studying the virulence and antibiotic resistance of UPEC with respect to various phylogenetic groups is of utmost importance in developing new therapeutic agents. Thus, in this study, we analysed the virulence factors, antibiotic resistance and phylogenetic groups among various UPEC isolates from children with UTIs. The phylogenetic analysis revealed that majority of the strains responsible for UTIs belonged to the phylogenetic groups B2 and D. Of the 58 E. coli isolates, 79·31% belonged to group B2, 15·51% to group D, 3·44% to group A and 1·72% to B1. Simultaneously, the number of virulence factors and antibiotic resistance exhibited were also significantly high in groups B2 and D compared to other groups. Among the isolates, 44·8% were multidrug resistant and of that 73% belonged to the phylogenetic group B2, indicating the compatibility of antibiotic resistance and certain strains carrying virulence factor genes. The antibiotic resistance profiling of UPEC strains elucidates that the antimicrobial agents such as chloramphenicol, cefoxitin, cefepime, ceftazidime might still be used in the therapy for treating UTIs. As the antibiotic resistance pattern of uropathogenic Escherichia coli varies depending on different geographical regions, the antibiotic resistance pattern from this study will help the physicians to effectively administer antibiotic therapy for urinary tract infections. In addition, the frequency of virulence factors and antibiotic resistance genes among various phylogenic groups could be effectively used to draw new targets for uropathogenic Escherichia coli antibiotic-independent therapies. The study emphasizes need of public awareness on multidrug resistance and for more prudent use of antimicrobials. © 2015 The Society for Applied Microbiology.

Evolution of Cost-Free Resistance under Fluctuating Drug Selection in Pseudomonas aeruginosa

PubMed Central

McCloskey, Nicholas; Hinz, Aaron J.; Dettman, Jeremy; Kassen, Rees

2017-01-01

ABSTRACT Antibiotic resistance evolves rapidly in response to drug selection, but it can also persist at appreciable levels even after the removal of the antibiotic. This suggests that many resistant strains can both be resistant and have high fitness in the absence of antibiotics. To explore the conditions under which high-fitness, resistant strains evolve and the genetic changes responsible, we used a combination of experimental evolution and whole-genome sequencing to track the acquisition of ciprofloxacin resistance in the opportunistic pathogen Pseudomonas aeruginosa under conditions of constant and fluctuating antibiotic delivery patterns. We found that high-fitness, resistant strains evolved readily under fluctuating but not constant antibiotic conditions and that their evolution was underlain by a trade-off between resistance and fitness. Whole-genome sequencing of evolved isolates revealed that resistance was gained through mutations in known resistance genes and that second-site mutations generally compensated for costs associated with resistance in the fluctuating treatment, leading to the evolution of cost-free resistance. Our results suggest that current therapies involving intermittent administration of antibiotics are contributing to the maintenance of antibiotic resistance at high levels in clinical settings. IMPORTANCE Antibiotic resistance is a global problem that greatly impacts human health. How resistance persists, even in the absence of antibiotic treatment, is thus a public health problem of utmost importance. In this study, we explored the antibiotic treatment conditions under which cost-free resistance arises, using experimental evolution of the bacterium Pseudomonas aeruginosa and the quinolone antibiotic ciprofloxacin. We found that intermittent antibiotic treatment led to the evolution of cost-free resistance and demonstrate that compensatory evolution is the mechanism responsible for cost-free resistance. Our results suggest that discontinuous administration of antibiotic may be contributing to the high levels of antibiotic resistance currently found worldwide. PMID:28744479

Resistance pattern of breakthrough urinary tract infections in children on antibiotic prophylaxis.

PubMed

Nateghian, Ali Reza; Robinson, Joan L; Mohandessi, Shahab; Hooman, Nakysa

2009-01-01

Prophylactic antibiotics are commonly used for prevention of urinary tract infections (UTIs) in children. It was postulated that the organisms and resistance patterns of breakthrough infections would differ with the choice of antimicrobial prophylaxis. This was a retrospective descriptive study of all breakthroughs UTI from 2000 to 2006 in children over 1 month of age discharged from a referral children's hospital in Tehran, Iran on continuous antibiotic prophylaxis for UTIs. Fifty-seven children discharged on prophylaxis had breakthrough UTIs of which 32 (56%) had a previously diagnosed urinary tract anomaly. Escherichia coli was responsible for the majority of infections irrespective of choice of prophylaxis. Thirty-three of 56 breakthrough UTIs (59%) were with organisms that were resistant to the prophylactic antibiotic. There was an increased incidence of resistance to prophylaxis in children on cefixime (16 of 22; 78%) when compared with children on cephalexin (7 of 19; 37%; p=0.02) and a trend toward increased resistance when compared with children on trimethoprim-sulfamethoxasole (3 of 8; 37%) (p=0.10). In conclusion, the resistance pattern of organisms causing breakthrough UTIs varies with the choice of prophylaxis which should be taken into consideration in chosing empiric therapy for such infections.

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.

Association of metal tolerance with multiple antibiotic resistance of bacteria isolated from drinking water.

PubMed

Calomiris, J J; Armstrong, J L; Seidler, R J

1984-06-01

Bacterial isolates from the drinking water system of an Oregon coastal community were examined to assess the association of metal tolerance with multiple antibiotic resistance. Positive correlations between tolerance to high levels of Cu2+, Pb2+, and Zn2+ and multiple antibiotic resistance were noted among bacteria from distribution waters but not among bacteria from raw waters. Tolerances to higher levels of Al3+ and Sn2+ were demonstrated more often by raw water isolates which were not typically multiple antibiotic resistant. A similar incidence of tolerance to Cd2+ was demonstrated by isolates of both water types and was not associated with multiple antibiotic resistance. These results suggest that simultaneous selection phenomena occurred in distribution water for bacteria which exhibited unique patterns of tolerance to Cu2+, Pb2+, and Zn2+ and antibiotic resistance.

A systematic review and meta-analysis of the effects of antibiotic consumption on antibiotic resistance

PubMed Central

2014-01-01

Background Greater use of antibiotics during the past 50 years has exerted selective pressure on susceptible bacteria and may have favoured the survival of resistant strains. Existing information on antibiotic resistance patterns from pathogens circulating among community-based patients is substantially less than from hospitalized patients on whom guidelines are often based. We therefore chose to assess the relationship between the antibiotic resistance pattern of bacteria circulating in the community and the consumption of antibiotics in the community. Methods Both gray literature and published scientific literature in English and other European languages was examined. Multiple regression analysis was used to analyse whether studies found a positive relationship between antibiotic consumption and resistance. A subsequent meta-analysis and meta-regression was conducted for studies for which a common effect size measure (odds ratio) could be calculated. Results Electronic searches identified 974 studies but only 243 studies were considered eligible for inclusion by the two independent reviewers who extracted the data. A binomial test revealed a positive relationship between antibiotic consumption and resistance (p < .001) but multiple regression modelling did not produce any significant predictors of study outcome. The meta-analysis generated a significant pooled odds ratio of 2.3 (95% confidence interval 2.2 to 2.5) with a meta-regression producing several significant predictors (F(10,77) = 5.82, p < .01). Countries in southern Europe produced a stronger link between consumption and resistance than other regions. Conclusions Using a large set of studies we found that antibiotic consumption is associated with the development of antibiotic resistance. A subsequent meta-analysis, with a subsample of the studies, generated several significant predictors. Countries in southern Europe produced a stronger link between consumption and resistance than other regions so efforts at reducing antibiotic consumption may need to be strengthened in this area. Increased consumption of antibiotics may not only produce greater resistance at the individual patient level but may also produce greater resistance at the community, country, and regional levels, which can harm individual patients. PMID:24405683

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

PubMed Central

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

2016-01-01

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

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

PubMed Central

2017-01-01

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

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

PubMed

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

2017-01-01

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

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.

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

PubMed

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

2018-06-01

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

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.

Association of metal tolerance with multiple antibiotic resistance of bacteria isolated from drinking water.

PubMed Central

Calomiris, J J; Armstrong, J L; Seidler, R J

1984-01-01

Bacterial isolates from the drinking water system of an Oregon coastal community were examined to assess the association of metal tolerance with multiple antibiotic resistance. Positive correlations between tolerance to high levels of Cu2+, Pb2+, and Zn2+ and multiple antibiotic resistance were noted among bacteria from distribution waters but not among bacteria from raw waters. Tolerances to higher levels of Al3+ and Sn2+ were demonstrated more often by raw water isolates which were not typically multiple antibiotic resistant. A similar incidence of tolerance to Cd2+ was demonstrated by isolates of both water types and was not associated with multiple antibiotic resistance. These results suggest that simultaneous selection phenomena occurred in distribution water for bacteria which exhibited unique patterns of tolerance to Cu2+, Pb2+, and Zn2+ and antibiotic resistance. PMID:6742841

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

PubMed

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

2013-01-01

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

Relatively high antibiotic resistance among heterotrophic bacteria from arctic fjord sediments than water - Evidence towards better selection pressure in the fjord sediments

NASA Astrophysics Data System (ADS)

Hatha, A. A. Mohamed; Neethu, C. S.; Nikhil, S. M.; Rahiman, K. M. Mujeeb; Krishnan, K. P.; Saramma, A. V.

2015-12-01

The objective of this study was to determine the prevalence of antibiotic resistance among aerobic heterotrophic bacteria and coliform bacteria from water and sediment of Kongsfjord. The study was based on the assumption that arctic fjord environments are relatively pristine and offer very little selection pressure for drug resistant mutants. In order to test the hypothesis, 200 isolates belonging to aerobic heterotrophic bacteria and 114 isolates belonging to coliforms were tested against 15 antibiotics belonging to 5 different classes such as beta lactams, aminoglycosides, quinolones, sulpha drugs and tetracyclines. Resistance to beta lactam and extended spectrum beta lactam (ESBL) antibiotics was considerably high and they found to vary significantly (p < 0.05) between heterotrophic and coliform bacteria. Though the coliforms showed significantly high level of antibiotic resistance against ESBL's extent and diversity of antibiotic resistance (as revealed by multiple antibiotic resistance index and resistance patterns), was high in the aerobic heterotrophic bacteria. Most striking observation was that isolates from fjord sediments (both heterotrophic bacteria and coliforms) in general showed relatively high prevalence of antibiotic resistance against most of the antibiotics tested, indicating to better selection pressure for drug resistance mutants in the fjord sediments.

Prevalence and Pattern of Antibiotic Resistant Strains of Helicobacter Pylori Infection in ASEAN

PubMed

Vilaichone, Ratha Korn; Quach, Duc Trong; Yamaoka, Yoshio; Sugano, Ken; Mahachai, Varocha

2018-05-26

Objective: Antibiotic resistance has significantly impact on eradication rates for H. pylori infection and remains important cause of treatment failure worldwide including ASEAN countries. The aim of this study was to survey the prevalence and antibiotic resistant pattern of H. pylori infection in ASEAN. Methods: This study was a survey among 26 experts from 9 ASEAN countries including Thailand, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore and Vietnam whom attended a meeting to develop the ASEAN consensus on H. pylori management in Bangkok in November 2015. A questionnaire was sent to each member of the consensus meeting. The detail of the questionnaire included information about prevalence of H. pylori infection, facilities to perform H. pylori culture, molecular testing for antibiotic resistance and antibiotic resistance rate in their countries. Results: H. pylori infection remain common in ASEAN ranging from 20% in Malaysia, 21-54% in Thailand and 69% in Myanmar. Most of ASEAN countries can perform H. pylori cultures and antibiotic susceptibility tests except Laos and Cambodia. In ASEAN countries, metronidazole resistant H pylori is quite common whereas amoxicillin resistance remain rare. Clarithromycin resistance results in a significant decrease in H. pylori eradication rate with clarithromycin-containing regimens. The prevalence of clarithromycin resistance varies in ASEAN countries being high in Vietnam (30%) and Cambodia (43%), moderate to high in Singapore (17%) and low in Malaysia (6.8%), Philippine (2%) and Myanmar (0%). In Thailand, clarithromycin resistance tends to higher in large cities (14%) than in rural areas (~3.7%). Conclusion: ASEAN countries should develop a standard protocol for regular susceptibility testing of H. pylori so that clinicians would be better able to choose reliably effective empiric therapies. The wide range of antibiotic resistance in ASEAN countries suggests that the preferred first line regimen should be depend on the local antibiotic resistance other than single recommendation. Creative Commons Attribution License

Long-term exposure to spaceflight conditions affects bacterial response to antibiotics.

PubMed

Juergensmeyer, M A; Juergensmeyer, E A; Guikema, J A

1999-01-01

Bacteria exposed to the spaceflight environment have been shown to have an increased growth rate and an increased resistance to antibiotics. The mechanism of resistance has not yet been identified, as the resistance is quickly lost upon return to Earth. To more fully characterize the spaceflight-induced resistance to antibiotics, 4 species of bacteria were exposed to microgravity for 4 months on the Space Station MIR. Upon return to Earth, these cultures were challenged with a suite of 12 antibiotics of varying modes of action. In contrast to reports from short-term space flights, we find that long-term exposure to microgravity causes bacteria to become more susceptible to most, but not all, antibiotics. Each species responds differently to the suite of antibiotics, frequently becoming less resistant, but occasionally more resistant to the antibiotic. A pattern enabling prediction of response is not yet discernible. While contradicting the results from short-term pure culture research, this experiment confirms results from astronaut and cosmonaut skin flora samples.

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

Antagonistic activities of some probiotic lactobacilli culture supernatant on Serratia marcescens swarming motility and antibiotic resistance.

PubMed

Vahedi-Shahandashti, Roya; Kasra-Kermanshahi, Rouha; Shokouhfard, Maliheh; Ghadam, Parinaz; Feizabadi, Mohammad Mehdi; Teimourian, Shahram

2017-12-01

Serratia marcescens , a potentially pathogenic bacterium, benefits from its swarming motility and resistance to antibiotic as two important virulence factors. Inappropriate use of antibiotics often results in drug resistance phenomenon in bacterial population. Use of probiotic bacteria has been recommended as partial replacement. In this study, we investigated the effects of some lactobacilli culture supernatant on swarming, motility and antibiotic resistance of S. marcescens . Antimicrobial activity of lactobacilli supernatant and susceptibility testing carried out on S. marcescens isolates. Pretreatment effect of lactobacilli culture supernatant on antibiotic - resistance pattern in S. marcescens was determined by comparison of the MIC of bacteria before and after the treatment. Our results showed that pretreatment with L. acidophilus ATCC 4356 supernatant can affect the resistance of Serratia strains against ceftriaxone, but it had no effect on the resistance to other antibiotics. Furthermore, culture supernatant of lactobacilli with concentrations greater than 2%, had an effect on the swarming ability of S. marcescens ATCC 13880 and inhibited it. Probiotic bacteria and their metabolites have the ability to inhibit virulence factors such as antibiotic resistance and swarming motility and can be used as alternatives to antibiotics.

Multiple antibiotic resistance patterns of rhizospheric bacteria isolated from Phragmites australis growing in constructed wetland for distillery effluent treatment.

PubMed

Chaturvedi, Sonal; Chandra, Ram; Rai, Vibhuti

2008-01-01

Susceptibility patterns of 12 different antibiotics were investigated against rhizospheric bacteria isolated from Phragmites australis from three different zones i.e. upper (0-5 cm), middle (5-10 cm), lower (10-15 cm) in constructed wetland system with and without distillery effluent. The major pollutants of distillery effluent were phenols, sulphide, heavy metals, and higher levels of biological oxygen demand (BOD), chemical oxygen demand (COD) etc. The antibiotic resistance properties of bacteria were correlated with the heavy metal tolerance (one of distillery pollutant). Twenty-two species from contaminated and seventeen species from non-contaminated site were tested by agar disc-diffusion method. The results revealed that more than 63% of total isolates were resistance towards one or more antibiotics tested from all the three different zones of contaminated sites. The multiple-drug resistance property was shown by total 8 isolates from effluent contaminated region out of which 3 isolates were from upper zone, 3 isolates from middle zone and 2 isolates were from lower zone. Results indicated that isolates from contaminated rhizosphere were found more resistant to antibiotics than isolates from non-contaminated rhizosphere. Further this study produces evidence suggesting that tolerance to antibiotics was acquired by isolates for the adaptation and detoxification of all the pollutants present in the effluent at contaminated site. This consequently facilitated the phytoremediation of effluent, which emerges the tolerance and increases resistance to antibiotics.

Antibiotic resistance among Escherichia coli isolates from stool samples of children aged 3 to 14 years from Ujjain, India

PubMed Central

2013-01-01

Background Antibiotic resistance is a major global public health concern, particularly in settings where few treatment options are available. Limited research has been done on antibiotic resistance in Escherichia coli of Indian children at community level. Therefore we studied antibiotic resistance patterns in E. coli isolates from stool samples of children aged 3-14 years from Ujjain, Central India, to investigate associations of resistance with demographic variables. Methods Children, 3-14 years of age, were included from 30 randomly selected villages of Palwa demographic surveillance site, Ujjain, India. Parents were interviewed using a questionnaire, and stool samples were collected from participating children. E. coli were isolated from stool samples (n = 529), and susceptibility testing to 18 different antibiotics was done using standard methods. Results The proportions of isolates resistant to various antibiotics were, nalidixic acid, (45%), tetracycline (37%), ampicillin (37%), sulfamethoxazole/trimethoprim (29%) and amoxicillin/clavulanic acid (29%). No isolates were resistant to imipenem. Overall, 72% of isolates were resistant to at least one antibiotic and 33% were multi-drug resistant. High rates of cross-resistance were seen for 15 (83%) of the antibiotics studied. E. coli isolates from children with literate mothers were more resistant to penicillins and fluoroquinolones. ESBL-producers comprised 9% of the isolates. Conclusion Antibiotic resistance and cross-resistance were common in E. coli from stools of children. Resistance rates were associated with maternal literacy. PMID:24124728

Diverse Antibiotic Resistance Genes in Dairy Cow Manure

PubMed Central

Wichmann, Fabienne; Udikovic-Kolic, Nikolina; Andrew, Sheila; Handelsman, Jo

2014-01-01

ABSTRACT Application of manure from antibiotic-treated animals to crops facilitates the dissemination of antibiotic resistance determinants into the environment. However, our knowledge of the identity, diversity, and patterns of distribution of these antibiotic resistance determinants remains limited. We used a new combination of methods to examine the resistome of dairy cow manure, a common soil amendment. Metagenomic libraries constructed with DNA extracted from manure were screened for resistance to beta-lactams, phenicols, aminoglycosides, and tetracyclines. Functional screening of fosmid and small-insert libraries identified 80 different antibiotic resistance genes whose deduced protein sequences were on average 50 to 60% identical to sequences deposited in GenBank. The resistance genes were frequently found in clusters and originated from a taxonomically diverse set of species, suggesting that some microorganisms in manure harbor multiple resistance genes. Furthermore, amid the great genetic diversity in manure, we discovered a novel clade of chloramphenicol acetyltransferases. Our study combined functional metagenomics with third-generation PacBio sequencing to significantly extend the roster of functional antibiotic resistance genes found in animal gut bacteria, providing a particularly broad resource for understanding the origins and dispersal of antibiotic resistance genes in agriculture and clinical settings. PMID:24757214

Antibiotic resistance of Campylobacter in raw retail chickens and imported chicken portions.

PubMed Central

Wilson, I. G.

2003-01-01

Campylobacter isolates from raw retail chickens (n = 434) sampled between 1998 and 2000 were tested for resistance to 12 antibiotics. Among 208 campylobacters tested, more than 90% of isolates were susceptible to 4 out of 9 antibiotics (nalidixic acid, erythromycin, chloramphenicol and gentamicin). Most campylobacters were resistant to 3 antibiotics and multiple resistance was found in 4%. Ciprofloxacin resistance was 11%. Campylobacter contamination (28%) in imported chickens (n = 150) was almost half that found in local whole chickens (50%), but the resistance of imported isolates (n = 42) was similar to that of local campylobacters. Resistance in isolates from imported chicken breasts was generally more common, but to only 4 antibiotics. Resistance patterns of chicken isolates were compared to human clinical isolates (n = 494), and a greater similarity was found between the clinical and local isolates than with imported campylobacters. Lower chloramphenicol resistance was found in clinical Campylobacter isolates than in those from chicken sources. PMID:14959786

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

PubMed

Kapoor, G; Sachdeva, N; Jain, S

2014-01-01

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

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

PubMed Central

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

2017-01-01

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

Growth Behavior of E. coli, Enterococcus and Staphylococcus Species in the Presence and Absence of Sub-inhibitory Antibiotic Concentrations: Consequences for Interpretation of Culture-Based Data.

PubMed

Heß, Stefanie; Gallert, Claudia

2016-11-01

Culture-based approaches are used to monitor, e.g., drinking water or bathing water quality and to investigate species diversity and antibiotic resistance levels in environmental samples. For health risk assessment, it is important to know whether the growing cultures display the actual abundance of, e.g., clinically relevant antibiotic resistance phenotypes such as vancomycin-resistant Enterococcus faecium/Enterococcus faecalis (VRE) or methicillin-resistant Staphylococcus aureus. In addition, it is important to know whether sub-inhibitory antibiotic concentrations, which are present in surface waters, favor the growth of antibiotic-resistant strains. Therefore, clinically relevant bacteria were isolated from different water sources and the growth behavior of 58 Escherichia coli, 71 Enterococcus, and 120 Staphylococcus isolates, belonging to different species and revealing different antibiotic resistance patterns, was studied with respect to "environmental" antibiotic concentrations. The finding that VRE could only be detected after specific enrichment can be explained by their slow growth compared to non-resistant strains. Interpreting their absence in standardized culture-based methods as nonexistent might be a fallacy. Sub-inhibitory antibiotic concentrations that were detected in sewage and receiving river water did not specifically promote antibiotic-resistant strains. Generally, those antibiotics that influenced cell metabolism directly led to slightly reduced growth rates and less than maximal optical densities after 48 h of incubation.

Self-Medication with Antibiotics, Attitude and Knowledge of Antibiotic Resistance among Community Residents and Undergraduate Students in Northwest Nigeria.

PubMed

Ajibola, Olumide; Omisakin, Olusola Akintoye; Eze, Anthonius Anayochukwu; Omoleke, Semeeh Akinwale

2018-04-27

This study set out to evaluate self-medicated antibiotics and knowledge of antibiotic resistance among undergraduate students and community members in northern Nigeria. Antibiotic consumption pattern, source of prescription, illnesses commonly treated, attitude towards antibiotics, and knowledge of antibiotic resistance were explored using a structured questionnaire. Responses were analyzed and summarized using descriptive statistics. Of the 1230 respondents from undergraduate students and community members, prescription of antibiotics by a physician was 33% and 57%, respectively, amongst undergraduate students and community members. We tested the respondents’ knowledge of antibiotic resistance (ABR) and found that undergraduate students displayed less knowledge that self-medication could lead to ABR (32.6% and 42.2% respectively). Self-medication with antibiotics is highly prevalent in Northwest Nigeria, with most medicines being purchased from un-licensed stores without prescription from a physician. We also observed a significant gap in respondents’ knowledge of ABR. There is an urgent need for public health authorities in Nigeria to enforce existing laws on antibiotics sales and enlighten the people on the dangers of ABR.

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.

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

DTIC Science & Technology

2015-07-22

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

Enterobacteriaceae Isolated from the River Danube: Antibiotic Resistances, with a Focus on the Presence of ESBL and Carbapenemases.

PubMed

Kittinger, Clemens; Lipp, Michaela; Folli, Bettina; Kirschner, Alexander; Baumert, Rita; Galler, Herbert; Grisold, Andrea J; Luxner, Josefa; Weissenbacher, Melanie; Farnleitner, Andreas H; Zarfel, Gernot

2016-01-01

In a clinical setting it seems to be normal these days that a relevant proportion or even the majority of different bacterial species has already one or more acquired antibiotic resistances. Unfortunately, the overuse of antibiotics for livestock breeding and medicine has also altered the wild-type resistance profiles of many bacterial species in different environmental settings. As a matter of fact, getting in contact with resistant bacteria is no longer restricted to hospitals. Beside food and food production, the aquatic environment might also play an important role as reservoir and carrier. The aim of this study was the assessment of the resistance patterns of Escherichia coli and Klebsiella spp. out of surface water without prior enrichment and under non-selective culture conditions (for antibiotic resistance). In addition, the presence of clinically important extended spectrum beta lactamase (ESBL) and carbapenmase harboring Enterobacteriaceae should be investigated. During Joint Danube Survey 3 (2013), water samples were taken over the total course of the River Danube. Resistance testing was performed for 21 different antibiotics. Samples were additionally screened for ESBL or carbapenmase harboring Enterobacteriaceae. 39% of all isolated Escherichia coli and 15% of all Klebsiella spp. from the river Danube had at least one acquired resistance. Resistance was found against all tested antibiotics except tigecycline. Taking a look on the whole stretch of the River Danube the proportion of multiresistances did not differ significantly. In total, 35 ESBL harboring Enterobacteriaceae, 17 Escherichia coli, 13 Klebsiella pneumoniae and five Enterobacter spp. were isolated. One Klebsiella pneumoniae harboring NMD-1 carbapenmases and two Enterobacteriaceae with KPC-2 could be identified. Human generated antibiotic resistance is very common in E. coli and Klebsiella spp. in the River Danube. Even isolates with resistance patterns normally associated with intensive care units are present.

Emergence of antibiotic-resistant bacteria in patients with Fournier gangrene.

PubMed

Lin, Wei-Ting; Chao, Chien-Ming; Lin, Hsin-Lan; Hung, Ming-Chran; Lai, Chih-Cheng

2015-04-01

This study was conducted to investigate the bacteriology and associated patterns of antibiotic resistance Fournier gangrene. Patients with Fournier's gangrene from 2008 to 2012 were identified from the computerized database in a medical center in southern Taiwan. The medical records of all patients with Fournier's gangrene were reviewed retrospectively. There were 61 microorganisms, including 60 bacteria and one Candida spp, isolated from clinical wound specimens from 32 patients. The most common isolates obtained were Streptococcus spp. (n=12), Peptoniphilus spp. (n=8), Staphylococcus aureus (n=7), Escherichia coli (n=7), and Klebsiella pneumoniae (n=7). Among 21 strains of gram-negative bacilli, five (23.8%) were resistant to fluoroquinolones, and three isolates were resistant to ceftriaxone. Two E. coli strains produced extended-spectrum beta-lactamase. Four of the seven S. aureus isolates were methicillin-resistant. Among 15 anaerobic isolates, nine (60%) were resistant to penicillin, and eight (53.3%) were resistant to clindamycin. Four (26.7%) isolates were resistant to metronidazole. The only independent risk factor associated with mortality was inappropriate initial antibiotic treatment (p=0.021). Antibiotic-resistant bacteria are emerging in the clinical setting of Fournier gangrene. Clinicians should use broad-spectrum antibiotics initially to cover possible antibiotic-resistant bacteria.

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

PubMed Central

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

2017-01-01

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

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

PubMed

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

2016-12-12

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

Changing patterns and widening of antibiotic resistance in Shigella spp. over a decade (2000-2011), Andaman Islands, India.

PubMed

Bhattacharya, D; Bhattacharya, H; Sayi, D S; Bharadwaj, A P; Singhania, M; Sugunan, A P; Roy, S

2015-02-01

This study is a part of the surveillance study on childhood diarrhoea in the Andaman and Nicobar Islands; here we report the drug resistance pattern of recent isolates of Shigella spp. (2006-2011) obtained as part of that study and compare it with that of Shigella isolates obtained earlier during 2000-2005. During 2006-2011, stool samples from paediatric diarrhoea patients were collected and processed for isolation and identification of Shigella spp. Susceptibility to 22 antimicrobial drugs was tested and minimum inhibitory concentrations were determined for third-generation cephalosporins, quinolones, amoxicillin-clavulanic acid combinations and gentamicin. A wide spectrum of antibiotic resistance was observed in the Shigella strains obtained during 2006-2011. The proportions of resistant strains showed an increase from 2000-2005 to 2006-2011 in 20/22 antibiotics tested. The number of drug resistance patterns increased from 13 in 2000-2005 to 43 in 2006-2011. Resistance to newer generation fluoroquinolones, third-generation cephalosporins and augmentin, which was not observed during 2000-2005, appeared during 2006-2011. The frequency of resistance in Shigella isolates has increased substantially between 2000-2006 and 2006-2011, with a wide spectrum of resistance. At present, the option for antimicrobial therapy in shigellosis in Andaman is limited to a small number of drugs.

Prevalence of antibiotic resistance in commensal Escherichia coli among the children in rural hill communities of Northeast India.

PubMed

Singh, Ashish Kumar; Das, Saurav; Singh, Samer; Gajamer, Varsha Rani; Pradhan, Nilu; Lepcha, Yangchen Doma; Tiwari, Hare Krishna

2018-01-01

Commensal bacteria are the representative of the reservoir of antibiotic resistance genes present in a community. The usage of antibiotics along with the demographic factors is generally associated with an increase in antibiotics resistance in pathogens. Northeast (NE) India is untapped with regard to antibiotic resistance prevalence and spread. In the current study, the prevalence of antibiotic-resistant commensal Escherichia coli in pre-school and school-going children (n = 550, 1-14 years old) from the rural areas of the state of Sikkim-an NE Indian state, with respect to associated demographic factors was investigated. A total of 550 fecal E. coli isolates were collected during July 2015 to June 2017. A structured questionnaire was used to collect data to ascertain the potential factors associated with the carriage of antibiotic resistance E. coli among the children. Statistical analysis along with a logistic regression identified potential external factors affecting the observed antibiotic resistance pattern. The data indicated a high prevalence of resistance to common antibiotics like ampicillin (92%), ceftazidime (90%), cefoxitin (88%), streptomycin (40%) and tetracycline (36%), but no resistance to chloramphenicol. The resistance to the combination of penicillin and quinolone group of antibiotics was observed in fifty-two percent of the isolates. A positive correlation between the harboring of antibiotics resistant E. coli with different demographic factors was observed such as, with children living in nuclear family (vs joint family 63.15%, OR 0.18, 95% CI:0.11-0.28, p < 0.01), below higher secondary maternal education (vs college graduates 59.27% OR 0.75, 95% CI:0.55-1.02, p < 0.02). A close association between different demographic factors and the high prevalence of antibiotic-resistant commensal E. coli in the current study suggests a concern over rising misuse of antibiotics that warrants a future threat of emergence of multidrug-resistant pathogen isolates.

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.

LONG-TERM STARVATION-INDUCTED LOSS OF ANTIBIOTIC RESISTANCE IN BACTERIA

EPA Science Inventory

Escherichia coli, Pseudomonas fluorescens, and a Pseudomonas sp. strain 133B containing the pSa plasmid were starved in well water for up to 523 days. here were two patterns of apparent antibiotic resistance loss observed. n Pseudomonas sp. strain 133B, there was no apparent loss...

Insights in Nanoparticle-Bacterium Interactions: New Frontiers to Bypass Bacterial Resistance to Antibiotics.

PubMed

Diab, Roudayna; Khameneh, Bahman; Joubert, Olivier; Duval, Raphael

2015-01-01

Nanotechnology has been revealed as a fundamental approach for antibiotics delivery. In this paper, recent findings demonstrating the superiority of nanocarried-antibiotics over "naked" ones and the ways by which nanoparticles can help to overwhelm bacterial drug resistance are reviewed. The second part of this paper sheds light on nanoparticle-bacterium interaction patterns. Finally, key factors affecting the effectiveness of nanoparticles interactions with bacteria are discussed.

In vitro transfer of multiple resistance observed in vivo during a Salmonella london epidemic.

PubMed

Lantos, J; Marjai, E

1980-01-01

Between 1976 and 1978, waves of Salmonella london infections conveyed by raw meat and meat products were observed. The strains isolated during the epidemic were first susceptible then developed multiple antibiotic resistance. The identical antibiotic resistance patterns of the strain and their more frequent occurrence in hospital environments indicated plasmid-mediated resistance. R-plasmid transfer, minimum inhibition concentration and resistance elimination were studied in representative strains. The resistant S. london strain and transconjugants of Escherichia coli rendered resistant were compared. The results proved that multiple resistance was plasmid-mediated.

Diversity of herbaceous plants and bacterial communities regulates soil resistome across forest biomes.

PubMed

Hu, Hang-Wei; Wang, Jun-Tao; Singh, Brajesh K; Liu, Yu-Rong; Chen, Yong-Liang; Zhang, Yu-Jing; He, Ji-Zheng

2018-04-24

Antibiotic resistance is ancient and prevalent in natural ecosystems and evolved long before the utilization of synthetic antibiotics started, but factors influencing the large-scale distribution patterns of natural antibiotic resistance genes (ARGs) remain largely unknown. Here, a large-scale investigation over 4000 km was performed to profile soil ARGs, plant communities and bacterial communities from 300 quadrats across five forest biomes with minimal human impact. We detected diverse and abundant ARGs in forests, including over 160 genes conferring resistance to eight major categories of antibiotics. The diversity of ARGs was strongly and positively correlated with the diversity of bacteria, herbaceous plants and mobile genetic elements (MGEs). The ARG composition was strongly correlated with the taxonomic structure of bacteria and herbs. Consistent with this strong correlation, structural equation modelling demonstrated that the positive effects of bacterial and herb communities on ARG patterns were maintained even when simultaneously accounting for multiple drivers (climate, spatial predictors and edaphic factors). These findings suggest a paradigm that the interactions between aboveground and belowground communities shape the large-scale distribution of soil resistomes, providing new knowledge for tackling the emerging environmental antibiotic resistance. © 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.

A Three-Year Follow-Up Study of Antibiotic and Metal Residues, Antibiotic Resistance and Resistance Genes, Focusing on Kshipra-A River Associated with Holy Religious Mass-Bathing in India: Protocol Paper.

PubMed

Diwan, Vishal; Purohit, Manju; Chandran, Salesh; Parashar, Vivek; Shah, Harshada; Mahadik, Vijay K; Stålsby Lundborg, Cecilia; Tamhankar, Ashok J

2017-05-29

Antibiotic resistance (ABR) is one of the major health emergencies for global society. Little is known about the ABR of environmental bacteria and therefore it is important to understand ABR reservoirs in the environment and their potential impact on health. Quantitative and qualitative data will be collected during a 3-year follow-up study of a river associated with religious mass-bathing in Central India. Surface-water and sediment samples will be collected from seven locations at regular intervals for 3 years during religious mass-bathing and in absence of it to monitor water-quality, antibiotic residues, resistant bacteria, antibiotic resistance genes and metals. Approval has been obtained from the Ethics Committee of R.D. Gardi Medical College, Ujjain, India (No. 2013/07/17-311). The results will address the issue of antibiotic residues and antibiotic resistance with a focus on a river environment in India within a typical socio-behavioural context of religious mass-bathing. It will enhance our understanding about the relationship between antibiotic residue levels, water-quality, heavy metals and antibiotic resistance patterns in Escherichia coli isolated from river-water and sediment, and seasonal differences that are associated with religious mass-bathing. We will also document, identify and clarify the genetic differences/similarities relating to phenotypic antibiotic resistance in bacteria in rivers during religious mass-bathing or during periods when there is no mass-bathing.

Accumulation of antibiotics and heavy metals in meat duck deep litter and their role in persistence of antibiotic-resistant Escherichia coli in different flocks on one duck farm.

PubMed

Lin, Y; Zhao, W; Shi, Z D; Gu, H R; Zhang, X T; Ji, X; Zou, X T; Gong, J S; Yao, W

2017-04-01

Meat duck deep litter is considered to be an ideal environment for the evolution of bacterial antibiotic resistance if it is under poor management. The aim of this study was to characterize the accumulation of antibiotics and heavy metals in the deep litter and their role in the persistence of antibiotic resistance of Escherichia coli, and evaluate the service life of the deep litter. Samples were collected from initial, middle, and final stages of deep litter within 3 barns (zero, 4, and 8 rounds of meat duck fattening, d 34) and 9 flocks, with known consumption of antibiotics in the controlled trail. The feed and litter levels of consumed antibiotics and heavy metals were measured. E. coli (n = 147) was isolated and typed by Eric-PCR and the phylogenetic grouping technique, while minimal inhibitory concentrations of antibiotics and heavy metals were measured. This study confirmed the continuous accumulation of doxycycline and many heavy metals in the deep litter. The population of resistant certain bacteria to doxycycline (16 mg/L, 100 mg/L) or ofloxacin (8 g/mL, 50 g/mL) increased in the used deep litter (rounds 4 and 8). E. coli isolated from the 3 stages of sampling were highly resistant to ampicillin, tetracycline, florfenicol, and doxycycline. Increased resistance to ceftiofur, enrofloxacin, ofloxacin, and gentamicin were seen in the isolates from the final stage of deep litter. In addition, the percentage of isolates tolerant to zinc, copper, and cadmium and the numbers of Group-B2 isolates all increased in the used deep litter, and the isolates of each stage belonged predominantly to commensal groups. The antibiotic resistance of isolates with identical Eric-PCR patterns had improved from round 4 to 8, and differences still existed in the resistance profiles of isolates with identical Eric-PCR patterns from different barns of the same round. This study concluded that deep litter could be suitable for the evolution of bacterial antibiotic-resistance under conditions of continuous usage or accumulation of antibiotics and heavy metals without proper management. © 2016 Poultry Science Association Inc.

Seasonal Variations in Water-Quality, Antibiotic Residues, Resistant Bacteria and Antibiotic Resistance Genes of Escherichia coli Isolates from Water and Sediments of the Kshipra River in Central India.

PubMed

Diwan, Vishal; Hanna, Nada; Purohit, Manju; Chandran, Salesh; Riggi, Emilia; Parashar, Vivek; Tamhankar, Ashok J; Stålsby Lundborg, Cecilia

2018-06-17

To characterize the seasonal variation, over one year, in water-quality, antibiotic residue levels, antibiotic resistance genes and antibiotic resistance in Escherichia coli isolates from water and sediment of the Kshipra River in Central India. Water and sediment samples were collected from seven selected points from the Kshipra River in the Indian city of Ujjain in the summer, rainy season, autumn and winter seasons in 2014. Water quality parameters (physical, chemical and microbiological) were analyzed using standard methods. High-performance liquid chromatography⁻tandem mass spectrometry was used to determine the concentrations of antibiotic residues. In river water and sediment samples, antibiotic resistance and multidrug resistance patterns of isolated E. coli to 17 antibiotics were tested and genes coding for resistance and phylogenetic groups were detected using multiplex polymerase chain reaction. One-way analysis of variance (ANOVA) and Fisher tests were applied to determine seasonal variation. In river water, seasonal variation was significantly associated with various water quality parameters, presence of sulfamethoxazole residues, bacteria resistant to ampicillin, cefepime, meropenem, amikacin, gentamicin, tigecycline, multidrug resistance and CTX-M-1 gene. The majority of the Extended Spectrum Beta-Lactamase (ESBL)-producing E. coli isolates from river water and sediment in all different seasons belonged to phylogenetic group A or B1. Antibiotic pollution, resistance and resistance genes in the Kshipra River showed significant seasonal variation. Guidelines and regulatory standards are needed to control environmental dissemination of these “pollutants” in this holy river.

Comparison of antibiotic resistant Escherichia coli obtained from drinking water sources in northern Tanzania: a cross-sectional study.

PubMed

Lyimo, Beatus; Buza, Joram; Subbiah, Murugan; Smith, Woutrina; Call, Douglas R

2016-11-03

Antimicrobial resistance (AMR) is a growing and significant threat to public health on a global scale. Escherichia coli comprises Gram-negative, fecal-borne pathogenic and commensal bacteria that are frequently associated with antibiotic resistance. AMR E. coli can be ingested via food, water and direct contact with fecal contamination. We estimated the prevalence of AMR Escherichia coli from select drinking water sources in northern Tanzania. Water samples (n = 155) were collected and plated onto Hi-Crome E. coli and MacConkey agar. Presumptive E. coli were confirmed by using a uidA PCR assay. Antibiotic susceptibility breakpoint assays were used to determine the resistance patterns of each isolate for 10 antibiotics. Isolates were also characterized by select PCR genotyping and macro-restriction digest assays. E. coli was isolated from 71 % of the water samples, and of the 1819 E. coli tested, 46.9 % were resistant to one or more antibiotics. Resistance to ampicillin, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim was significantly higher (15-30 %) compared to other tested antibiotics (0-6 %; P < 0.05). Of the β-lactam-resistant isolates, bla TEM-1 was predominant (67 %) followed by bla CTX-M (17.7 %) and bla SHV-1 (6.0 %). Among the tetracycline-resistant isolates, tet(A) was predominant (57.4 %) followed by tet(B) (24.0 %). E. coli isolates obtained from these water sources were genetically diverse with few matching macro-restriction digest patterns. Water supplies in northern Tanzania may be a source of AMR E. coli for people and animals. Further studies are needed to identify the source of these contaminants and devise effective intervention strategies.

Occurrence of multi-antibiotic resistant Pseudomonas spp. in drinking water produced from karstic hydrosystems.

PubMed

Flores Ribeiro, Angela; Bodilis, Josselin; Alonso, Lise; Buquet, Sylvaine; Feuilloley, Marc; Dupont, Jean-Paul; Pawlak, Barbara

2014-08-15

Aquatic environments could play a role in the spread of antibiotic resistance genes by enabling antibiotic-resistant bacteria transferred through wastewater inputs to connect with autochthonous bacteria. Consequently, drinking water could be a potential pathway to humans and animals for antibiotic resistance genes. The aim of this study was to investigate occurrences of Escherichia coli and Pseudomonas spp. in drinking water produced from a karst, a vulnerable aquifer with frequent increases in water turbidity after rainfall events and run-offs. Water samples were collected throughout the system from the karstic springs to the drinking water tap during three non-turbid periods and two turbid events. E. coli densities in the springs were 10- to 1000-fold higher during the turbid events than during the non-turbid periods, indicating that, with increased turbidity, surface water had entered the karstic system and contaminated the spring water. However, no E. coli were isolated in the drinking water. In contrast, Pseudomonas spp. were isolated from the drinking water only during turbid events, while the densities in the springs were from 10- to 100-fold higher than in the non-turbid periods. All the 580 Pseudomonas spp. isolates obtained from the sampling periods were resistant (to between 1 and 10 antibiotics), with similar resistance patterns. Among all the Pseudomonas isolated throughout the drinking water production system, between 32% and 86% carried the major resistance pattern: ticarcillin, ticarcillin-clavulanic acid, cefsulodin, and/or aztreonam, and/or sulfamethoxazol-trimethoprim, and/or fosfomycin. Finally, 8 Pseudomonas spp. isolates, related to the Pseudomonas putida and Pseudomonas fluorescens species, were isolated from the drinking water. Thus, Pseudomonas could be involved in the dissemination of antibiotic resistance via drinking water during critical periods. Copyright © 2014 Elsevier B.V. All rights reserved.

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

PubMed

Decimo, Marilù; Silvetti, Tiziana; Brasca, Milena

2016-04-01

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

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

PubMed Central

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

2014-01-01

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

Epidemiology of Antibiotic and Heavy Metal Resistance in Bacteria: Resistance Patterns in Staphylococci Isolated from Populations Not Known to be Exposed to Heavy Metals

PubMed Central

Groves, David J.; Young, Frank E.

1975-01-01

Staphylococci were isolated from clinical specimens obtained from patients not known to be exposed to abnormal levels of heavy metals. The antibiotic and heavy metal resistance patterns of these strains were determined by using a disk diffusion test and computer sorting. Though not absolute, an association of resistance to mercury and tetracycline in coagulase-negative strains was found, in contrast to resistance to copper and penicillin in coagulase-producing strains. A high degree of correlation was observed between the resistance to phenyl mercury and inorganic mercury, but no correlation was obtained between resistance to methylmercury and other metals. In general, strains resistant to many agents were usually coagulase negative. A possible mechanism and implications of these associations are considered. PMID:1147592

LONG-TERM STARVATION-INDUCED LOSS OF APPARENT ANTIBIOTIC RESISTANCE IN CELLS CONTAINING THE PLASMID PSA

EPA Science Inventory

Escherichia coli, Pseudomonas fluorescens, and a Pseudomonas sp. strain 133B containing the pSa plasmid were starved in well water for up to 523 days. There were two patterns of apparent antibiotic resistance loss observed. In Pseudomonas sp. strain 133B, there was no apparent lo...

Antibiotic-Resistant Gram Negative Bacilli in Meals Delivered at a General Hospital, Italy

PubMed Central

Plano, Maria Rosa Anna; Di Noto, Anna Maria; Firenze, Alberto; Sciortino, Sonia; Mammina, Caterina

2009-01-01

This study aimed at detecting the presence of antibiotic-resistant Gram-negatives in samples of meals delivered at the University General Hospital of Palermo, Italy. Antibiotic resistant Gram negatives were isolated in July—September 2007 ffrom cold dishes and food contact surfaces and utensils. Bacterial strains were submitted to susceptibility test and subtyped by random amplification of polymorphic DNA (RAPD). Forty-six of 55 (83.6%) food samples and 14 of 17 (82.3%) environmental swabs were culture positive for Gram negative bacilli resistant to at least one group of antibacterial drugs. A total of 134 antibiotic resistant strains, 51 fermenters and 83 non-fermenters, were recovered. Fermenters and non-fermenters showed frequencies as high as 97.8% of resistance to two or more groups of antibiotics and non fermenters were 28.9% resistant to more than three groups. Molecular typing detected 34 different profiles among the fermenters and 68 among the non-fermenters. Antibiotic resistance was very common among both fermenters and non-fermenters. However, the wide heterogeneity of RAPD patterns seems to support a prominent role of cross-contamination rather than a clonal expansion of a few resistant isolates. A contribution of commensal Gram negatives colonizing foods to a common bacterial resistance pool should not been overlooked. PMID:19750189

Antibiotic-resistant gram negative bacilli in meals delivered at a general hospital, Italy.

PubMed

Plano, Maria Rosa Anna; Di Noto, Anna Maria; Firenze, Alberto; Sciortino, Sonia; Mammina, Caterina

2009-01-01

This study aimed at detecting the presence of antibiotic-resistant Gram-negatives in samples of meals delivered at the University General Hospital of Palermo, Italy. Antibiotic resistant Gram negatives were isolated in July-September 2007 ffrom cold dishes and food contact surfaces and utensils. Bacterial strains were submitted to susceptibility test and subtyped by random amplification of polymorphic DNA (RAPD). Forty-six of 55 (83.6%) food samples and 14 of 17 (82.3%) environmental swabs were culture positive for Gram negative bacilli resistant to at least one group of antibacterial drugs. A total of 134 antibiotic resistant strains, 51 fermenters and 83 non-fermenters, were recovered. Fermenters and non-fermenters showed frequencies as high as 97.8% of resistance to two or more groups of antibiotics and non fermenters were 28.9% resistant to more than three groups. Molecular typing detected 34 different profiles among the fermenters and 68 among the non-fermenters. Antibiotic resistance was very common among both fermenters and non-fermenters. However, the wide heterogeneity of RAPD patterns seems to support a prominent role of cross-contamination rather than a clonal expansion of a few resistant isolates. A contribution of commensal Gram negatives colonizing foods to a common bacterial resistance pool should not been overlooked.

Variability in Pediatric Infectious Disease Consultants' Recommendations for Management of Community-Acquired Pneumonia

PubMed Central

Hersh, Adam L.; Shapiro, Daniel J.; Newland, Jason G.; Polgreen, Philip M.; Beekmann, Susan E.; Shah, Samir S.

2011-01-01

Background Community-acquired pneumonia (CAP) is a common childhood infection. CAP complications, such as parapneumonic empyema (PPE), are increasing and are frequently caused by antibiotic-resistant organisms. No clinical guidelines currently exist for management of pediatric CAP and no published data exist about variations in antibiotic prescribing patterns. Our objectives were to describe variation in CAP clinical management for hospitalized children by pediatric infectious disease consultants and to examine associations between recommended antibiotic regimens and local antibiotic resistance levels. Methods We surveyed pediatric members of the Emerging Infections Network, which consists of 259 pediatric infectious disease physicians. Participants responded regarding their recommended empiric antibiotic regimens for hospitalized children with CAP with and without PPE and their recommendations for duration of therapy. Participants also provided information about the prevalence of penicillin non-susceptible S. pneumoniae and methicillin-resistant S. aureus (MRSA) in their community. Results We received 148 responses (57%). For uncomplicated CAP, respondents were divided between recommending beta-lactams alone (55%) versus beta-lactams in combination with another class (40%). For PPE, most recommended a combination of a beta-lactam plus an anti-MRSA agent, however, they were divided between clindamycin (44%) and vancomycin (57%). The relationship between reported antibiotic resistance and empiric regimen was mixed. We found no relationship between aminopenicillin use and prevalence of penicillin non-suscepetible S. pneumoniae or clindamycin use and clindamycin resistance, however, respondents were more likely to recommend an anti-MRSA agent when MRSA prevalence increased. Conclusions Substantial variability exists in recommendations for CAP management. Development of clinical guidelines via antimicrobial stewardship programs and dissemination of data about local antibiotic resistance patterns represent opportunities to improve care. PMID:21655259

Phenotypic and genotypic characterisation of multiple antibiotic-resistant Staphylococcus aureus exposed to subinhibitory levels of oxacillin and levofloxacin.

PubMed

Jo, Ara; Ahn, Juhee

2016-07-29

The emergence and spread of multidrug resistant methicillin-resistant Staphylococcus aureus (MDR-MRSA) has serious health consequences in the presence of sub-MIC antibiotics. Therefore, this study was designed to evaluate β-lactamase activity, efflux activity, biofilm formation, and gene expression pattern in Staphylococcus aureus KACC 10778, S. aureus ATCC 15564, and S. aureus CCARM 3080 exposed to sublethal concentrations of levofloxacin and oxacillin. The decreased MICs were observed in S. aureus KACC and S. aureus ATCC when exposed to levofloxacin and oxacillin, while and S. aureus CCARM remained resistance to streptomycin (512 μg/mL) in the presence of levofloxacin and imipenem (>512 μg/mL) in the presence of oxacillin. The considerable increase in extracellular and membrane-bound β-lactamase activities was observed in S. aureus ATCC exposed to oxacillin (>26 μmol/min/mL). The antibiotic susceptibility of all strains exposed to EPIs (CCCP and PAβN) varied depending on the classes of antibiotics. The relative expression levels of adhesion-related genes (clfA, clfB, fnbA, fnnB, and icaD), efflux-related genes (norB, norC, and qacA/B), and enterotoxin gene (sec) were increased more than 5-fold in S. aureus CCARM. The eno and qacA/B genes were highly overexpressed by more than 12- and 9-folds, respectively, in S. aureus CCARM exposed to levofloxacin. The antibiotic susceptibility, lactamase activity, biofilm-forming ability, efflux activity, and gene expression pattern varied with the intrinsic antibiotic resistance of S. aureus KACC, S. aureus ATCC, and S. aureus CCARM exposed to levofloxacin and oxacillin. This study would provide useful information for better understating of combination therapy related to antibiotic resistance mechanisms and open the door for designing effective antibiotic treatment protocols to prevent excessive use of antibiotics in clinical practice.

Antibiotics resistance of Helicobacter pylori in children with upper gastrointestinal symptoms in Hangzhou, China.

PubMed

Shu, Xiaoli; Yin, Guofeng; Liu, Mingnan; Peng, Kerong; Zhao, Hong; Jiang, Mizu

2018-06-01

The decreasing eradication rate of Helicobacter pylori is mainly because of the progressive increase in its resistance to antibiotics. Studies on antimicrobial susceptibility of H. pylori in children are limited. This study aimed to investigate the resistance rates and patterns of H. pylori strains isolated from children. Gastric mucosa biopsy samples obtained from children who had undergone upper gastrointestinal endoscopy were cultured for H. pylori, and susceptibility to six antibiotics (clarithromycin, amoxicillin, gentamicin, furazolidone, metronidazole, and levofloxacin) was tested from 2012-2014. A total of 545 H. pylori strains were isolated from 1390 children recruited. The total resistance rates of H. pylori to clarithromycin, metronidazole, and levofloxacin were 20.6%, 68.8%, and 9.0%, respectively. No resistance to amoxicillin, gentamicin, and furazolidone was detected. 56.1% strains were single resistance, 19.6% were resistant to more than one antibiotic, 16.7% for double resistance, and 2.9% for triple resistance in 413 strains against any antibiotic. And the H. pylori resistance rate increased significantly from 2012-2014. There was no significant difference in the resistance rates to clarithromycin, metronidazole, and levofloxacin between different gender, age groups, and patients with peptic ulcer diseases or nonulcer diseases. Antibiotic resistance was indicated in H. pylori strains isolated from children in Hangzhou, and it increased significantly during the 3 years. Our data strongly support current guidelines, which recommend antibiotic susceptibility tests prior to eradication therapy. © 2018 John Wiley & Sons Ltd.

Discovery, research, and development of new antibiotics: the WHO priority list of antibiotic-resistant bacteria and tuberculosis.

PubMed

Tacconelli, Evelina; Carrara, Elena; Savoldi, Alessia; Harbarth, Stephan; Mendelson, Marc; Monnet, Dominique L; Pulcini, Céline; Kahlmeter, Gunnar; Kluytmans, Jan; Carmeli, Yehuda; Ouellette, Marc; Outterson, Kevin; Patel, Jean; Cavaleri, Marco; Cox, Edward M; Houchens, Chris R; Grayson, M Lindsay; Hansen, Paul; Singh, Nalini; Theuretzbacher, Ursula; Magrini, Nicola

2018-03-01

The spread of antibiotic-resistant bacteria poses a substantial threat to morbidity and mortality worldwide. Due to its large public health and societal implications, multidrug-resistant tuberculosis has been long regarded by WHO as a global priority for investment in new drugs. In 2016, WHO was requested by member states to create a priority list of other antibiotic-resistant bacteria to support research and development of effective drugs. We used a multicriteria decision analysis method to prioritise antibiotic-resistant bacteria; this method involved the identification of relevant criteria to assess priority against which each antibiotic-resistant bacterium was rated. The final priority ranking of the antibiotic-resistant bacteria was established after a preference-based survey was used to obtain expert weighting of criteria. We selected 20 bacterial species with 25 patterns of acquired resistance and ten criteria to assess priority: mortality, health-care burden, community burden, prevalence of resistance, 10-year trend of resistance, transmissibility, preventability in the community setting, preventability in the health-care setting, treatability, and pipeline. We stratified the priority list into three tiers (critical, high, and medium priority), using the 33rd percentile of the bacterium's total scores as the cutoff. Critical-priority bacteria included carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa, and carbapenem-resistant and third-generation cephalosporin-resistant Enterobacteriaceae. The highest ranked Gram-positive bacteria (high priority) were vancomycin-resistant Enterococcus faecium and meticillin-resistant Staphylococcus aureus. Of the bacteria typically responsible for community-acquired infections, clarithromycin-resistant Helicobacter pylori, and fluoroquinolone-resistant Campylobacter spp, Neisseria gonorrhoeae, and Salmonella typhi were included in the high-priority tier. Future development strategies should focus on antibiotics that are active against multidrug-resistant tuberculosis and Gram-negative bacteria. The global strategy should include antibiotic-resistant bacteria responsible for community-acquired infections such as Salmonella spp, Campylobacter spp, N gonorrhoeae, and H pylori. World Health Organization. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

PubMed Central

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

2018-01-01

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

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.

A Three-Year Follow-Up Study of Antibiotic and Metal Residues, Antibiotic Resistance and Resistance Genes, Focusing on Kshipra—A River Associated with Holy Religious Mass-Bathing in India: Protocol Paper

PubMed Central

Diwan, Vishal; Purohit, Manju; Chandran, Salesh; Parashar, Vivek; Shah, Harshada; Mahadik, Vijay K.; Stålsby Lundborg, Cecilia; Tamhankar, Ashok J.

2017-01-01

Background: Antibiotic resistance (ABR) is one of the major health emergencies for global society. Little is known about the ABR of environmental bacteria and therefore it is important to understand ABR reservoirs in the environment and their potential impact on health. Method/Design: Quantitative and qualitative data will be collected during a 3-year follow-up study of a river associated with religious mass-bathing in Central India. Surface-water and sediment samples will be collected from seven locations at regular intervals for 3 years during religious mass-bathing and in absence of it to monitor water-quality, antibiotic residues, resistant bacteria, antibiotic resistance genes and metals. Approval has been obtained from the Ethics Committee of R.D. Gardi Medical College, Ujjain, India (No. 2013/07/17-311). Results: The results will address the issue of antibiotic residues and antibiotic resistance with a focus on a river environment in India within a typical socio-behavioural context of religious mass-bathing. It will enhance our understanding about the relationship between antibiotic residue levels, water-quality, heavy metals and antibiotic resistance patterns in Escherichia coli isolated from river-water and sediment, and seasonal differences that are associated with religious mass-bathing. We will also document, identify and clarify the genetic differences/similarities relating to phenotypic antibiotic resistance in bacteria in rivers during religious mass-bathing or during periods when there is no mass-bathing. PMID:28555050

Antibiotic resistance pattern of Helicobacter pylori strains isolated in Italy during 2010-2016.

PubMed

Fiorini, Giulia; Zullo, Angelo; Saracino, Ilaria Maria; Pavoni, Matteo; Vaira, Dino

2018-04-24

Bacterial resistance toward the most used antibiotics is increasing in Helicobacter pylori strains worldwide. Emergence of multidrug resistance significantly affects the efficacy of standard therapy regimens. Therefore, monitoring for primary antimicrobial resistance is essential for H. pylori management in clinical practice. H. pylori isolates obtained from patients consecutively observed in a single center were tested for primary resistance by using E-test method. Bacterial strains showing MIC values >0.5, >8 and >1 mg/L toward clarithromycin, metronidazole and levofloxacin, respectively, were considered resistant. The trend of antibiotic prevalence, either single or combined, during 2010-2016 was assessed. Antibiotic susceptibility data were available in 1424 (82.3%) out of 1730 tested patients. The overall resistance for all the three antibiotics showed an increasing trend from 2010 to 2013 (clarithromycin: from 19% to 35.6%; metronidazole: from 33.6% to 45.3%; levofloxacin: from 19% to 29.7%; p < .001), when a plateau until 2016 was observed (clarithromycin: 35.9%; metronidazole: 40.2%; levofloxacin: 29.3%). A similar trend occurred for clarithromycin-metronidazole combined resistance rate (2010: 11.4%; 2013: 28.2%; 2016: 21.9%). Our data suggest that prevalence of primary resistance in H. pylori isolates toward the most frequently used antibiotics probably reached a plateau in the last years.

An overview of resistance profiles ESKAPE pathogens from 2010-2015 in a tertiary respiratory center in Romania.

PubMed

Peneş, Nicolae Ovidiu; Muntean, Andrei Alexandru; Moisoiu, Adriana; Muntean, Mădălina Maria; Chirca, Alexandru; Bogdan, Miron Alexandru; Popa, Mircea Ioan

2017-01-01

Lower respiratory tract infections (LRTIs) is an umbrella term that covers a wide spectrum of diseases, comprising mild and severe, acute and chronic conditions. A wide spectrum of pathogens can be implicated, from viruses to pyogenic and atypical bacteria. A special place should be reserved for slow growing bacteria (Mycobacteria spp., Nocardia spp.) and parasites (i.e., hydatic cysts caused by Echinococcus granulosus). The objective of this study is to observe, analyze and establish the drug susceptibility patterns for Enterococcus spp., Staphylococcus aureus, Klebsiella spp., Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp. (the ESKAPE pathogens) in the "Marius Nasta" Institute for Pulmonary Medicine (MNIPM), Bucharest, Romania. A retrospective healthcare record based study was undertaken to establish the drug susceptibility patterns. We assessed all antibiograms of the ESKAPE pathogens isolated from respiratory samples from adult inpatients hospitalized between 2010-2015 at the MNIPM. We analyzed 2859 isolates (61% of the 4683 ESKAPE isolates). P. aeruginosa was the most frequent pathogen, while Enterococcus spp. and Enterobacter spp. were practically non-present. The antibiotic profile of P. aeruginosa isolates presented more resistance in the Intensive Care Unit (ICU)÷Surgery wards, probably resulting from antibiotic pressure. The other non-fermenter, A. baumannii, while less frequent (and the only pathogen more frequent in the surgery department) had an even more resistant profile, to almost all antibiotics, with the exception of Colistin. Methicillin-resistant S. aureus (MRSA) accounted for about 60% of all isolates, more in the ICU÷Surgery ward. K. pneumoniae presents a less resistance and shows more stability when analyzing the antibiogram pattern in the Medical wards. For methodological or procedural reasons, Enterococcus spp. and Enterobacter spp. were underrepresented in the study. Interventional programs comprising antibiotic stewardship and active surveillance need to be implemented to alleviate the antibiotic profile. Further research needs to focus on more detailed characterization of the molecular mechanisms leading to the high resistance detailed herein. This study adds to the body of literature reporting the antibiotic resistance landscape in Romania, for these highly resistant pathogens.

Urinary tract infections in the infant.

PubMed

Arshad, Mehreen; Seed, Patrick C

2015-03-01

Urinary tract infection (UTI) in an infant may be the first indication of an underlying renal disorder. Early recognition and initiation of adequate therapy for UTI is important to reduce the risk of long-term renal scarring. Ampicillin and gentamicin are traditionally the empiric treatment of choice; however, local antibiotic resistance patterns should be considered. Maternal antibiotics during pregnancy also increase the risk of resistant pathogens during neonatal UTI. Long-term management after the first UTI in infants remains controversial because of lack of specific studies in this age group and the risk-benefit issues for antibiotic prophylaxis between reduced recurrent disease and emergent antibiotic resistance. Copyright © 2015 Elsevier Inc. All rights reserved.

Campaign Preparation for Complex Initiatives: A Person-Centered Approach to Audience Segmentation of Parents' Antibiotic Stewardship.

PubMed

Smith, Rachel A; MacGeorge, Erina L; Hackman, Nicole M; M'ikanatha, Nkuchia M

2017-10-25

The evolution of antibiotic resistance is outpacing the speed at which new antibiotics will reach the marketplace. To slow the rate of resistance, people need to engage in antibiotic stewardship, which includes acts to prevent the spread of bacteria and judicious use of antibiotics to treat infections. This study identified the patterns and predictors of antibiotic stewardship behaviors of parents (N = 516) related to their children. The latent class analysis revealed three profiles of parental stewardship, labeled Stewards, Requesters, and Non-Stewards. The findings implied different campaign goals: to encourage Stewards to follow through on their intentions, to encourage Requesters to stop asking providers for antibiotics when their children have ear infections, and to influence Non-Stewards to accept medical advice when an antibiotic is not indicated and to dispose of leftover antibiotics. The covariate analysis provided theoretical insight into the strategies to pursue in campaigns targeting these three groups. For example, parents who perceived antibiotic-resistant infections as less serious health conditions, felt less worry when thinking about their child getting an antibiotic-resistant infection, and had stronger misattributions of antibiotics' efficacy to treat multiple symptoms were more likely to be Requesters and Non-Stewards, instead of Stewards.

Microscale insights into pneumococcal antibiotic mutant selection windows

PubMed Central

Sorg, Robin A.; Veening, Jan-Willem

2015-01-01

The human pathogen Streptococcus pneumoniae shows alarming rates of antibiotic resistance emergence. The basic requirements for de novo resistance emergence are poorly understood in the pneumococcus. Here we systematically analyse the impact of antibiotics on S. pneumoniae at concentrations that inhibit wild type cells, that is, within the mutant selection window. We identify discrete growth-inhibition profiles for bacteriostatic and bactericidal compounds, providing a predictive framework for distinction between the two classifications. Cells treated with bacteriostatic agents show continued gene expression activity, and real-time mutation assays link this activity to the development of genotypic resistance. Time-lapse microscopy reveals that antibiotic-susceptible pneumococci display remarkable growth and death bistability patterns in response to many antibiotics. We furthermore capture the rise of subpopulations with decreased susceptibility towards cell wall synthesis inhibitors (heteroresisters). We show that this phenomenon is epigenetically inherited, and that heteroresistance potentiates the accumulation of genotypic resistance. PMID:26514094

Antibiotic resistome in a large-scale healthy human gut microbiota deciphered by metagenomic and network analyses.

PubMed

Feng, Jie; Li, Bing; Jiang, Xiaotao; Yang, Ying; Wells, George F; Zhang, Tong; Li, Xiaoyan

2018-01-01

The human gut microbiota is an important reservoir of antibiotic resistance genes (ARGs). A metagenomic approach and network analysis were used to establish a comprehensive antibiotic resistome catalog and to obtain co-occurrence patterns between ARGs and microbial taxa in fecal samples from 180 healthy individuals from 11 different countries. In total, 507 ARG subtypes belonging to 20 ARG types were detected with abundances ranging from 7.12 × 10 -7 to 2.72 × 10 -1 copy of ARG/copy of 16S-rRNA gene. Tetracycline, multidrug, macrolide-lincosamide-streptogramin, bacitracin, vancomycin, beta-lactam and aminoglycoside resistance genes were the top seven most abundant ARG types. The multidrug ABC transporter, aadE, bacA, acrB, tetM, tetW, vanR and vanS were shared by all 180 individuals, suggesting their common occurrence in the human gut. Compared to populations from the other 10 countries, the Chinese population harboured the most abundant ARGs. Moreover, LEfSe analysis suggested that the MLS resistance type and its subtype 'ermF' were representative ARGs of the Chinese population. Antibiotic inactivation, antibiotic target alteration and antibiotic efflux were the dominant resistance mechanism categories in all populations. Procrustes analysis revealed that microbial phylogeny structured the antibiotic resistome. Co-occurrence patterns obtained via network analysis implied that 12 species might be potential hosts of 58 ARG subtypes. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

Staphylococcus aureus carriage rates and antibiotic resistance patterns in patients with acne vulgaris.

PubMed

Delost, Gregory R; Delost, Maria E; Armile, James; Lloyd, Jenifer

2016-04-01

Overuse of antibiotics has led to the development of antibiotic-resistant strains of Staphylococcus aureus, which are occurring more frequently within the community. We sought to determine whether long-term antibiotic therapy for acne alter the carriage rate and antibiotic resistance profiles of S aureus. This was a prospective, cross-sectional, quasiexperimental study. Samples of anterior nares were obtained from dermatology patients given a diagnosis of acne vulgaris (n = 263) who were treated with antibiotics (n = 142) or who were not treated with antibiotics (n = 121). Specimens were tested for the presence of S aureus by growth on mannitol salt agar and then isolated on 5% sheep blood agar. Identification was confirmed based on colonial morphology, Gram stain, catalase, and coagulase testing. Antibiotic susceptibility testing was performed using the VITEK 2 system (bioMerieux, Marcy-l'Étoile, France). The S aureus carriage rate was significantly lower in patients with acne treated with antibiotics (6.3%) compared with those not treated with antibiotics (15.7%; P = .016). The percentage of S aureus isolates resistant to 1 or more antibiotics did not significantly differ between the 2 groups (P = .434). Cross-sectional study, patient compliance, and effects of prior acne treatments are limitations. Treatment of patients with acne using antibiotics decreases the S aureus carriage rate but does not significantly alter the antibiotic resistance rates. Copyright © 2015 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

All purulence is local – epidemiology and management of skin and soft tissue infections in three urban emergency departments

PubMed Central

2013-01-01

Background Skin and soft tissue infection (SSTIs) are commonly treated in emergency departments (EDs). While the precise role of antibiotics in treating SSTIs remains unclear, most SSTI patients receive empiric antibiotics, often targeted toward methicillin-resistant Staphylococcus aureus (MRSA). The goal of this study was to assess the efficiency with which ED clinicians targeted empiric therapy against MRSA, and to identify factors that may allow ED clinicians to safely target antibiotic use. Methods We performed a retrospective analysis of patient visits for community-acquired SSTIs to three urban, academic EDs in one northeastern US city during the first quarter of 2010. We examined microbiologic patterns among cultured SSTIs, and relationships between clinical and demographic factors and management of SSTIs. Results Antibiotics were prescribed to 86.1% of all patients. Though S. aureus (60% MRSA) was the most common pathogen cultured, antibiotic susceptibility differed between adult and pediatric patients. Susceptibility of S. aureus from ED SSTIs differed from published local antibiograms, with greater trimethoprim resistance and less fluoroquinolone resistance than seen in S. aureus from all hospital sources. Empiric antibiotics covered the resultant pathogen in 85.3% of cases, though coverage was frequently broader than necessary. Conclusions Though S. aureus remained the predominant pathogen in community-acquired SSTIs, ED clinicians did not accurately target therapy toward the causative pathogen. Incomplete local epidemiologic data may contribute to this degree of discordance. Future efforts should seek to identify when antibiotic use can be narrowed or withheld. Local, disease-specific antibiotic resistance patterns should be publicized with the goal of improving antibiotic stewardship. PMID:24359038

How should we respond to the emergence of plasmid-mediated colistin resistance in humans and animals?

PubMed

Al-Tawfiq, Jaffar A; Laxminarayan, Ramanan; Mendelson, Marc

2017-01-01

The widespread use of antibiotics in humans and animals has contributed to growing rates of antibiotic resistance. Previously treatable bacterial infections now require the last line of antibiotics or are untreatable. The current antibiotic of last resort for carbapenem-resistant Gram-negative bacterial infections is often colistin. Evidence for the shifting pattern of colistin resistance and how the international community should respond are discussed in this review. The literature on colistin resistance was reviewed. Plasmid-mediated colistin resistance encoded by mcr-1 was first documented in China during the routine surveillance of food animals. This has been followed by similar reports across a wide geographic area, in humans, animals, and the environment. The mcr-1 gene has been reported among human isolates in 29 countries, related to environmental samples in four countries, and in food animals and other animals in 28 countries. More recently, a second gene encoding resistance, mcr-2, has been isolated from porcine and bovine Escherichia coli. The emergence and horizontal transmission of colistin resistance highlights the need for heightened stewardship efforts across the One Health platform for this antibiotic of last resort, and indeed for all antibiotics used in animals and humans. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Assessing the Knowledge, Attitudes and Behaviors of Human and Animal Health Students towards Antibiotic Use and Resistance: A Pilot Cross-Sectional Study in the UK.

PubMed

Dyar, Oliver James; Hills, Holly; Seitz, Lara-Turiya; Perry, Alex; Ashiru-Oredope, Diane

2018-01-30

The Global Action Plan on Antimicrobial Resistance highlights the importance of training all healthcare professionals. No study has assessed patterns of students' knowledge, attitudes and practices concerning antibiotic use simultaneously across different healthcare course types. We conducted a cross-sectional multi-center survey among UK students. The survey was advertised through local survey coordinators at 25 universities. The online survey was accessible from 10th October to 17th November 2016 (before European Antibiotic Awareness Day). A total of 255 students from 25 universities participated, including students on medicine, pharmacy, nursing, physician associate, dentistry and veterinary medicine courses. Antibiotic resistance was considered to be a more important global challenge than climate change, obesity or food security ( p < 0.001). Most students (95%) believed that antibiotic resistance will be a problem for their future practice, but fewer (69%) thought that the antibiotics they will prescribe, administer or dispense will contribute to the problem. A fifth of students felt they had sufficient knowledge of antibiotic use for their future work. Our exploratory study suggests that UK human and animal healthcare students are aware of the importance of antibiotic resistance, but many still have certain misconceptions. Campaigns and improved educational efforts applying behavioral insights methodology could address these.

Antibiotic Resistance Patterns of Outpatient Pediatric Urinary Tract Infections

PubMed Central

Edlin, Rachel S.; Shapiro, Daniel J.; Hersh, Adam L.; Copp, Hillary L.

2014-01-01

Purpose We characterize the current national patterns of antibiotic resistance of outpatient pediatric urinary tract infection. Materials and Methods We examined outpatient urinary isolates from patients younger than 18 years in 2009 using The Surveillance Network®, a database with antibiotic susceptibility results and patient demographic data from 195 United States hospitals. We determined the prevalence and antibiotic resistance patterns for the 6 most common uropathogens, ie Escherichia coli, Proteus mirabilis, Klebsiella, Enterobacter, Pseudomonas aeruginosa and Enterococcus. We compared differences in uropathogen prevalence between males and females using chi-square analysis. Results We identified 25,418 outpatient urinary isolates. E. coli was the most common uropathogen overall but the prevalence of E. coli was higher among females (83%) than males (50%, p <0.001). Other common species among males were Enterococcus (17%), P. mirabilis (11%) and Klebsiella (10%). However, these uropathogens each accounted for 5% or less of female isolates (p <0.001). Resistance among E. coli was highest for trimethoprim-sulfamethoxazole (24%) but lower for nitrofurantoin (less than 1%) and cephalothin (15%). Compared to 2002 Surveillance Network data, E. coli resistance rates increased for trimethoprim-sulfamethoxazole (from 23% to 31% in males and from 20% to 23% in females) and ciprofloxacin (from 1% to 10% and from 0.6% to 4%, respectively). Conclusions E. coli remains the most common pediatric uropathogen. Although widely used, trimethoprim-sulfamethoxazole is a poor empirical choice for pediatric urinary tract infections in many areas due to high resistance rates. First-generation cephalosporins and nitrofurantoin are appropriate narrow-spectrum alternatives given their low resistance rates. Local antibiograms should be used to assist with empirical urinary tract infection treatment. PMID:23369720

Antibiotic resistance patterns of outpatient pediatric urinary tract infections.

PubMed

Edlin, Rachel S; Shapiro, Daniel J; Hersh, Adam L; Copp, Hillary L

2013-07-01

We characterize the current national patterns of antibiotic resistance of outpatient pediatric urinary tract infection. We examined outpatient urinary isolates from patients younger than 18 years in 2009 using The Surveillance Network®, a database with antibiotic susceptibility results and patient demographic data from 195 United States hospitals. We determined the prevalence and antibiotic resistance patterns for the 6 most common uropathogens, ie Escherichia coli, Proteus mirabilis, Klebsiella, Enterobacter, Pseudomonas aeruginosa and Enterococcus. We compared differences in uropathogen prevalence between males and females using chi-square analysis. We identified 25,418 outpatient urinary isolates. E. coli was the most common uropathogen overall but the prevalence of E. coli was higher among females (83%) than males (50%, p <0.001). Other common species among males were Enterococcus (17%), P. mirabilis (11%) and Klebsiella (10%). However, these uropathogens each accounted for 5% or less of female isolates (p <0.001). Resistance among E. coli was highest for trimethoprim-sulfamethoxazole (24%) but lower for nitrofurantoin (less than 1%) and cephalothin (15%). Compared to 2002 Surveillance Network data, E. coli resistance rates increased for trimethoprim-sulfamethoxazole (from 23% to 31% in males and from 20% to 23% in females) and ciprofloxacin (from 1% to 10% and from 0.6% to 4%, respectively). E. coli remains the most common pediatric uropathogen. Although widely used, trimethoprim-sulfamethoxazole is a poor empirical choice for pediatric urinary tract infections in many areas due to high resistance rates. First-generation cephalosporins and nitrofurantoin are appropriate narrow-spectrum alternatives given their low resistance rates. Local antibiograms should be used to assist with empirical urinary tract infection treatment. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Antibiotic Resistant Salmonella and Vibrio Associated with Farmed Litopenaeus vannamei

PubMed Central

Banerjee, Sanjoy; Ooi, Mei Chen; Shariff, Mohamed; Khatoon, Helena

2012-01-01

Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed individual and multiple antibiotic resistance patterns. Five Vibrio species having individual and multiple antibiotic resistance were also identified. They were Vibrio cholerae (18.3%), V. mimicus (16.7%), V. parahaemolyticus (10%), V. vulnificus (6.7%), and V. alginolyticus (1.7%). Farm owners should be concerned about the presence of these pathogenic bacteria which also contributes to human health risk and should adopt best management practices for responsible aquaculture to ensure the quality of shrimp. PMID:22619583

Comparative analysis of antibiotic resistance and phylogenetic group patterns in human and porcine urinary tract infectious Escherichia coli.

PubMed

Hancock, Viktoria; Nielsen, Eva Møller; Krag, Louise; Engberg, Jørgen; Klemm, Per

2009-11-01

Urinary tract infections (UTIs) are one of the most common infectious diseases in humans and domestic animals such as pigs. The most frequent infectious agent in such infections is Escherichia coli. Virulence characteristics of E. coli UTI strains range from highly virulent pyelonephritis strains to relatively benign asymptomatic bacteriuria strains. Here we analyse a spectrum of porcine and human UTI E. coli strains with respect to their antibiotic resistance patterns and their phylogenetic groups, determined by multiplex PCR. The clonal profiles of the strains differed profoundly; whereas human strains predominantly belonged to clonal types B2 and D, these were not seen among the porcine strains, which all belonged to the E. coli clonal groups A and B1. Contrary to the human strains, the majority of the porcine strains were multidrug resistant. The distinct profiles of the porcine strains suggest selective pressure due to extensive antibiotic use.

Mounting resistance of uropathogens to antimicrobial agents: A retrospective study in patients with chronic bacterial prostatitis relapse.

PubMed

Stamatiou, Konstantinos; Pierris, Nikolaos

2017-07-01

Despite recent progress in the management of chronic bacterial prostatitis (CBP), many cases relapse. Increased drug resistance patterns of responsible bacteria have been proposed as the most probable causative factor. Driven by the limited number of previous studies addressing this topic, we aimed to study whether antibiotic resistance increases in patients with CBP when relapse occurs. A secondary aim of this study was to determine the resistance patterns of responsible bacteria from patients with CBP. The study material consisted of bacterial isolates from urine and/or prostatic secretions obtained from patients with CBP. Bacterial identification was performed by using the Vitek 2 Compact system and susceptibility testing was performed by disc diffusion and/or the Vitek 2 system. Interpretation of susceptibility results was based on Clinical and Laboratory Standards Institute guidelines. A total of 253 samples from patients diagnosed with CBP for the first time (group A) and 137 samples from relapsing patients with a history of CBP and previous antibiotic treatment (group B) were analyzed. A significant reduction in bacterial resistance to the less used antibiotics (TMP-SMX, tetracyclines, aminoglycosides, penicillins, and macrolides) was noted. An increase in resistance to quinolones of many bacteria that cause CBP was also noted with the increase in resistance of enterococcus strains being alarming. Comparison of the resistance profile of CBP-responsible bacteria between samples from first-time-diagnosed patients and samples from relapsing patients revealed notable differences that could be attributed to previous antibiotic treatment.

The model of fungal population dynamics affected by nystatin

NASA Astrophysics Data System (ADS)

Voychuk, Sergei I.; Gromozova, Elena N.; Sadovskiy, Mikhail G.

Fungal diseases are acute problems of the up-to-day medicine. Significant increase of resistance of microorganisms to the medically used antibiotics and a lack of new effective drugs follows in a growth of dosage of existing chemicals to solve the problem. Quite often such approach results in side effects on humans. Detailed study of fungi-antibiotic dynamics can identify new mechanisms and bring new ideas to overcome the microbial resistance with a lower dosage of antibiotics. In this study, the dynamics of the microbial population under antibiotic treatment was investigated. The effects of nystatin on the population of Saccharomyces cerevisiae yeasts were used as a model system. Nystatin effects were investigated both in liquid and solid media by viability tests. Dependence of nystatin action on osmotic gradient was evaluated in NaCl solutions. Influences of glucose and yeast extract were additionally analyzed. A "stepwise" pattern of the cell death caused by nystatin was the most intriguing. This pattern manifested in periodical changes of the stages of cell death against stages of resistance to the antibiotic. The mathematical model was proposed to describe cell-antibiotic interactions and nystatin viability effects in the liquid medium. The model implies that antibiotic ability to cause a cells death is significantly affected by the intracellular compounds, which came out of cells after their osmotic barriers were damaged

A historical legacy of antibiotic utilization on bacterial seed banks in sediments

PubMed Central

Junier, Thomas; Bayrychenko, Zhanna; Filippidou, Sevasti; Beck, Karin; Greub, Gilbert; Bürgmann, Helmut

2018-01-01

The introduction of antibiotics for both medical and non-medical purposes has had a positive effect on human welfare and agricultural output in the past century. However, there is also an important ecological legacy regarding the use of antibiotics and the consequences of increased levels of these compounds in the environment as a consequence of their use and disposal. This legacy was investigated by quantifying two antibiotic resistance genes (ARG) conferring resistance to tetracycline (tet(W)) and sulfonamide (sul1) in bacterial seed bank DNA in sediments. The industrial introduction of antibiotics caused an abrupt increase in the total abundance of tet(W) and a steady increase in sul1. The abrupt change in tet(W) corresponded to an increase in relative abundance from ca. 1960 that peaked around 1976. This pattern of accumulation was highly correlated with the abundance of specific members of the seed bank community belonging to the phylum Firmicutes. In contrast, the relative abundance of sul1 increased after 1976. This correlated with a taxonomically broad spectrum of bacteria, reflecting sul1 dissemination through horizontal gene transfer. The accumulation patterns of both ARGs correspond broadly to the temporal scale of medical antibiotic use. Our results show that the bacterial seed bank can be used to look back at the historical usage of antibiotics and resistance prevalence. PMID:29312823

Antibiotic Resistance Patterns of Pseudomonas spp. Isolated from the River Danube

PubMed Central

Kittinger, Clemens; Lipp, Michaela; Baumert, Rita; Folli, Bettina; Koraimann, Günther; Toplitsch, Daniela; Liebmann, Astrid; Grisold, Andrea J.; Farnleitner, Andreas H.; Kirschner, Alexander; Zarfel, Gernot

2016-01-01

Spread and persistence of antibiotic resistance pose a severe threat to human health, yet there is still lack of knowledge about reservoirs of antibiotic resistant bacteria in the environment. We took the opportunity of the Joint Danube Survey 3 (JDS3), the world's biggest river research expedition of its kind in 2013, to analyse samples originating from different sampling points along the whole length of the river. Due to its high clinical relevance, we concentrated on the characterization of Pseudomonas spp. and evaluated the resistance profiles of Pseudomonas spp. which were isolated from eight sampling points. In total, 520 Pseudomonas isolates were found, 344 (66.0%) isolates were identified as Pseudomonas putida, and 141 (27.1%) as Pseudomonas fluorescens, all other Pseudomonas species were represented by less than five isolates, among those two P. aeruginosa isolates. Thirty seven percent (37%) of all isolated Pseudomonas species showed resistance to at least one out of 10 tested antibiotics. The most common resistance was against meropenem (30.4%/158 isolates) piperacillin/tazobactam (10.6%/55 isolates) and ceftazidime (4.2%/22 isolates). 16 isolates (3.1%/16 isolates) were multi-resistant. For each tested antibiotic at least one resistant isolate could be detected. Sampling points from the upper stretch of the River Danube showed more resistant isolates than downriver. Our results suggest that antibiotic resistance can be acquired by and persists even in Pseudomonas species that are normally not in direct contact with humans. A possible scenario is that these bacteria provide a reservoir of antibiotic resistance genes that can spread to related human pathogens by horizontal gene transfer. PMID:27199920

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

NASA Astrophysics Data System (ADS)

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

2018-03-01

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

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

PubMed

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

2015-10-01

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

Characterization of a chromosomally integrated luxCDABE marker for investigation of shiga toxin-producing Escherichia coli O91:H21 shedding in cattle

NASA Astrophysics Data System (ADS)

Hong, Yingying; Mathew, Alan G.

2011-06-01

Shiga toxin-producing Escherichia coli (STEC) O91:H21 has been recognized as a potential life-threatening foodborne pathogen and is commonly involved in human infections in European countries. Fecal shedding of the organism by cattle is considered to be the ultimate source for contaminations. Studies examining STEC shedding patterns often include inoculation of strains carrying antibiotic resistance makers for identifiable recovery. However, indigenous intestinal microflora exhibiting similar antibiotic resistance patterns can confound such studies. Such was the case in a study by our group when attempting to characterize shedding patterns of O91:H21 in calves. A chromosomally integrated bioluminescence marker using a luxCDABE cassette from Photorhabdus luminescens was developed in O91:H21 to overcome such shortcomings of antibiotic resistance markers during animal challenge experiment. The marker was validated in various aspects and was shown to have no impact on metabolic reactions, isotype virulence gene patterns, cost to growth, and additionally demonstrated high in vitro stability. Together, the results indicated that a chromosomally integrated luxCDABE based marker may be a superior system for the study of STEC colonization and shedding in cattle.

Comparative Study on Antibiotic Resistance and DNA Profiles of Salmonella enterica Serovar Typhimurium Isolated from Humans, Retail Foods, and the Environment in Shanghai, China.

PubMed

Zhang, Zengfeng; Cao, Chenyang; Liu, Bin; Xu, Xuebin; Yan, Yanfei; Cui, Shenghui; Chen, Sheng; Meng, Jianghong; Yang, Baowei

2018-05-09

We characterized antibiotic resistance profiles, antibiotic resistance-associated genes, and pulsed-field gel electrophoresis (PFGE) patterns of 145 Salmonella enterica serotype Typhimurium isolates from human infections and retail foods that were possibly responsible for salmonellosis outbreaks from 2008 to 2012 in Shanghai, China. Resistance to at least three antibiotics was found in 66.7% of chicken isolates, 76.5% of duck isolates, 77.8% of pork isolates, and 80.5% of human isolates. Seven antibiotic resistance phenotypes were detected in chicken isolates, 16 in pork isolates, 17 in duck isolates, and 50 in human isolates. No significant difference (p > 0.05) was found between Salmonella isolates derived from human salmonellosis and from retail foods in terms of the percent resistance of ampicillin, amoxicillin/clavulanic acid, ceftiofur, ceftriaxone, nalidixic acid, chloramphenicol, gentamicin, kanamycin, streptomycin, tetracycline, sulfisoxazole, and sulfamethoxazole/trimethoprim. PFGE using XbaI and BlnI showed that some Salmonella isolates recovered from human infections and retail foods had same or highly similar genetic profile. Same or similar antibiotic resistance profiles, antibiotic resistance associated genes (i.e., qnrA, qnrB, qnrS, aac(6')-Ib, and oqxAB), gene cassettes (i.e., aadA2, dfrA12-aadA2, and aadA1), and mutations were detected in those isolates that exhibited high genetic similarities. These findings highlighted the frequent presence of Salmonella Typhimurium in retail chicken, pork, duck, and humans.

Use of AFLP, plasmid typing and phenotyping in a comparative study to assess genetic diversity of Shigella flexneri strains.

PubMed Central

Herrera, S.; Cabrera, R.; Ramirez, M. M.; Usera, M. A.; Echeita, M. A.

2002-01-01

Shigella flexneri infections are one of the main causes of acute diarrhoea in Cuba. Twenty strains isolated from sporadic cases in nine different Cuban provinces were characterized. Serotyping, antibiotic-resistance typing, plasmid-typing and AFLP-typing were used to determine their suitability for use in epidemiological studies of S. flexneri. The predominant serotypes were serotype 6 (35%) and serotype 2 (35%). Eleven different plasmid profiles were detected (Diversity Index = 0.92). AFLP-typing discriminated 12 different patterns (DI = 0.95), these patterns were not coincident with plasmid-typing patterns. Both techniques combined distinguished 14 patterns among the 20 studied strains (DI = 0.99). There was no consistent relationship between plasmid-typing and AFLP-typing patterns or antibiotic-resistance typing patterns. Ninety-five percent of S. flexneri strains were multiresistant. PMID:12558326

Bacteria causing bacteremia in pediatric cancer patients presenting with febrile neutropenia--species distribution and susceptibility patterns.

PubMed

Miedema, Karin G E; Winter, Rik H L J; Ammann, Roland A; Droz, Sara; Spanjaard, Lodewijk; de Bont, Eveline S J M; Kamps, Willem A; van de Wetering, Marianne D; Tissing, Wim J E

2013-09-01

Infections are a major cause of morbidity and mortality in pediatric cancer patients. The aim of this study was to establish the microbiological spectrum and the susceptibility patterns of bacteremia-causing bacteria in pediatric cancer patients with febrile neutropenia in relation to the use of prophylactic and empirical antibiotics. We analyzed positive blood cultures of pediatric cancer patients presenting with febrile neutropenia between 2004 and 2011 in Groningen and Amsterdam (the Netherlands) and in Bern (Switzerland), using different antibiotic prophylactic and empirical regimens. A total of 156 patients with 202 bacteremias, due to 248 bacteria species, were enrolled. The majority (73%) of bacteremias were caused by Gram-positive bacteria. Gram-negative bacteria, especially Pseudomonas aeruginosa, were observed significantly more often in Bern, where no fluoroquinolone prophylaxis was used. Ciprofloxacin-resistant bacteria were cultured more often from patients who did receive ciprofloxacin prophylaxis, compared to the patients who did not (57 versus 11%, p = 0.044). Gram-positive bacteria predominated in this study. We showed that the use of prophylactic antibiotics in pediatric cancer patients was associated with increased resistance rates, which needs further study. The strategy for empiric antimicrobial therapy for febrile neutropenia should be adapted to local antibiotic resistance patterns.

Antibiotic Cycling and Antibiotic Mixing: Which One Best Mitigates Antibiotic Resistance?

PubMed Central

Peña-Miller, Rafael; Gori, Fabio; Iredell, Jonathan

2017-01-01

Abstract Can we exploit our burgeoning understanding of molecular evolution to slow the progress of drug resistance? One role of an infection clinician is exactly that: to foresee trajectories to resistance during antibiotic treatment and to hinder that evolutionary course. But can this be done at a hospital-wide scale? Clinicians and theoreticians tried to when they proposed two conflicting behavioral strategies that are expected to curb resistance evolution in the clinic, these are known as “antibiotic cycling” and “antibiotic mixing.” However, the accumulated data from clinical trials, now approaching 4 million patient days of treatment, is too variable for cycling or mixing to be deemed successful. The former implements the restriction and prioritization of different antibiotics at different times in hospitals in a manner said to “cycle” between them. In antibiotic mixing, appropriate antibiotics are allocated to patients but randomly. Mixing results in no correlation, in time or across patients, in the drugs used for treatment which is why theorists saw this as an optimal behavioral strategy. So while cycling and mixing were proposed as ways of controlling evolution, we show there is good reason why clinical datasets cannot choose between them: by re-examining the theoretical literature we show prior support for the theoretical optimality of mixing was misplaced. Our analysis is consistent with a pattern emerging in data: neither cycling or mixing is a priori better than the other at mitigating selection for antibiotic resistance in the clinic. Key words: antibiotic cycling, antibiotic mixing, optimal control, stochastic models. PMID:28096304

Antibiotic Cycling and Antibiotic Mixing: Which One Best Mitigates Antibiotic Resistance?

PubMed

Beardmore, Robert Eric; Peña-Miller, Rafael; Gori, Fabio; Iredell, Jonathan

2017-04-01

Can we exploit our burgeoning understanding of molecular evolution to slow the progress of drug resistance? One role of an infection clinician is exactly that: to foresee trajectories to resistance during antibiotic treatment and to hinder that evolutionary course. But can this be done at a hospital-wide scale? Clinicians and theoreticians tried to when they proposed two conflicting behavioral strategies that are expected to curb resistance evolution in the clinic, these are known as "antibiotic cycling" and "antibiotic mixing." However, the accumulated data from clinical trials, now approaching 4 million patient days of treatment, is too variable for cycling or mixing to be deemed successful. The former implements the restriction and prioritization of different antibiotics at different times in hospitals in a manner said to "cycle" between them. In antibiotic mixing, appropriate antibiotics are allocated to patients but randomly. Mixing results in no correlation, in time or across patients, in the drugs used for treatment which is why theorists saw this as an optimal behavioral strategy. So while cycling and mixing were proposed as ways of controlling evolution, we show there is good reason why clinical datasets cannot choose between them: by re-examining the theoretical literature we show prior support for the theoretical optimality of mixing was misplaced. Our analysis is consistent with a pattern emerging in data: neither cycling or mixing is a priori better than the other at mitigating selection for antibiotic resistance in the clinic. : antibiotic cycling, antibiotic mixing, optimal control, stochastic models. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Antibiotic resistance and virulence traits in clinical and environmental Enterococcus faecalis and Enterococcus faecium isolates.

PubMed

Rathnayake, I U; Hargreaves, M; Huygens, F

2012-07-01

This study compared virulence and antibiotic resistance traits in clinical and environmental Enterococcus faecalis and Enterococcus faecium isolates. E. faecalis isolates harboured a broader spectrum of virulence determinants compared to E. faecium isolates. The virulence traits Cyl-A, Cyl-B, Cyl-M, gel-E, esp and acm were tested and environmental isolates predominantly harboured gel-E (80% of E. faecalis and 31.9% of E. faecium) whereas esp was more prevalent in clinical isolates (67.8% of E. faecalis and 70.4% of E. faecium). E. faecalis and E. faecium isolated from water had different antibiotic resistance patterns compared to those isolated from clinical samples. Linezolid resistance was not observed in any isolates tested and vancomycin resistance was observed only in clinical isolates. Resistance to other antibiotics (tetracycline, gentamicin, ciprofloxacin and ampicillin) was detected in both clinical and water isolates. Clinical isolates were more resistant to all the antibiotics tested compared to water isolates. Multi-drug resistance was more prevalent in clinical isolates (71.2% of E. faecalis and 70.3% of E. faecium) compared to water isolates (only 5.7% E. faecium). tet L and tet M genes were predominantly identified in tetracycline-resistant isolates. All water and clinical isolates resistant to ciprofloxacin and ampicillin contained mutations in the gyrA, parC and pbp5 genes. A significant correlation was found between the presence of virulence determinants and antibiotic resistance in all the isolates tested in this study (p<0.05). The presence of antibiotic resistant enterococci, together with associated virulence traits, in surface recreational water could be a public health risk. Copyright © 2012 Elsevier GmbH. All rights reserved.

Empirical treatment of bacterial keratitis: an international survey of corneal specialists.

PubMed

Austin, Ariana; Schallhorn, Julie; Geske, Mike; Mannis, Mark; Lietman, Tom; Rose-Nussbaumer, Jennifer

2017-08-01

New antibiotic agents and changing susceptibility patterns may have changed the empirical treatment of bacterial keratitis. Our objective in this study was to survey cornea specialists' practice patterns in the initial treatment of bacterial ulcers. This study consisted of a short online survey emailed to members of the Cornea Society listserv for an international sample of cornea specialists. Data collection began July 2014 and ended October 2014. A total of 1009 surveys were emailed, and we received 140 (14%) responses. The majority of US clinicians surveyed (n=83, 80%) chose fortified antibiotics empirically, with 55% (n=57) selecting fortified vancomycin and 16% (n=17) using fluoroquinolone alone. International respondents were twice as likely to use fluoroquinolone monotherapy (31%, n=11, p=0.07) and less likely to use fortified vancomycin (33%, n=12, p=0.03). Forty-five per cent (n=46) of US respondents reported that their initial antibiotic choice covered methicillin-resistant Staphylococcus aureus , compared with 22% (n=8) of international respondents (p<0.01). Overall, respondents who were concerned about availability of antibiotics and toxicity were 20.86 (p<0.001) and 7.48 (p<0.001) times more likely to choose fluoroquinolone monotherapy, respectively. If respondents' primary considerations were broad spectrum coverage or antibiotic resistance they had 7.10 (p<0.001) and 12.51 (p<0.001) times the odds of using fortified vancomycin, respectively. Practice patterns for the initial treatment of bacterial keratitis vary with clinicians in the USA being more likely to use fortified antibiotics versus fluoroquinolone monotherapy and more concerned with resistant organisms than their international peers.

[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.

Treating Wisely: The Surgeon's Role in Antibiotic Stewardship.

PubMed

Leeds, Ira L; Fabrizio, Anne; Cosgrove, Sara E; Wick, Elizabeth C

2017-05-01

: Antibiotic resistance continues to receive national attention as a leading public health threat. In 2015, President Barack Obama proposed a National Action Plan to Combat Antibiotic-Resistant Bacteria to curb the rise of "superbugs," bacteria resistant to antibiotics of last resort. Whereas many antibiotics are prescribed appropriately to treat infections, there continue to be a large number of inappropriately prescribed antibiotics. Although much of the national attention with regards to stewardship has focused on primary care providers, there is a significant opportunity for surgeons to embrace this national imperative and improve our practices. Local quality improvement efforts suggest that antibiotic misuse for surgical disease is common. Opportunities exist as part of day-to-day surgical care as well as through surgeons' interactions with nonsurgeon colleagues and policy experts. This article discusses the scope of the antibiotic misuse in surgery for surgical patients, and provides immediate practice improvements and also advocacy efforts surgeons can take to address the threat. We believe that surgical antibiotic prescribing patterns frequently do not adhere to evidence-based practices; surgeons are in a position to mitigate their ill effects; and antibiotic stewardship should be a part of every surgeons' practice.

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.

Group A streptococcus colonies from a single throat swab can have heterogeneous antimicrobial susceptibility patterns.

PubMed

Vandevoorde, Aurélie; Ascenzo, Sabrina; Miendje Deyi, Veronique Yvette; Mascart, Georges; Mansbach, Anne-Laure; Landsberg, Marguerite; Dreze, Pierre; Steer, Andrew C; Van Melderen, Laurence; Smeesters, Pierre R

2013-03-01

This study describes for the first time heterogeneity of antibiotic resistance profiles among group A Streptococcus isolates originating from a single throat swab in patients with acute pharyngitis. For each throat swab, 10 group A Streptococcus colonies were randomly selected from the primary plate and subcultured to a secondary plate. These isolates were characterized by various phenotypic and genotypic methods. Our results demonstrated that differing antibiotic resistance profiles were present in 19% of pediatric patients with acute pharyngitis before antimicrobial treatment. This heterogeneity likely resulted from horizontal gene transfer among streptococcal isolates sharing the same genetic background. As only a minority of colonies displayed antibiotic resistance among these heterogeneous samples, a classical diagnostic antibiogram would have classified them in most instances as "susceptible," although therapeutic failure could be caused by the proliferation of resistant strains after initiation of antibiotic treatment.

Clinical Options for the Treatment of Urinary Tract Infections in Children

PubMed Central

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

2014-01-01

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

Transcriptome Profiling of Antimicrobial Resistance in Pseudomonas aeruginosa.

PubMed

Khaledi, Ariane; Schniederjans, Monika; Pohl, Sarah; Rainer, Roman; Bodenhofer, Ulrich; Xia, Boyang; Klawonn, Frank; Bruchmann, Sebastian; Preusse, Matthias; Eckweiler, Denitsa; Dötsch, Andreas; Häussler, Susanne

2016-08-01

Emerging resistance to antimicrobials and the lack of new antibiotic drug candidates underscore the need for optimization of current diagnostics and therapies to diminish the evolution and spread of multidrug resistance. As the antibiotic resistance status of a bacterial pathogen is defined by its genome, resistance profiling by applying next-generation sequencing (NGS) technologies may in the future accomplish pathogen identification, prompt initiation of targeted individualized treatment, and the implementation of optimized infection control measures. In this study, qualitative RNA sequencing was used to identify key genetic determinants of antibiotic resistance in 135 clinical Pseudomonas aeruginosa isolates from diverse geographic and infection site origins. By applying transcriptome-wide association studies, adaptive variations associated with resistance to the antibiotic classes fluoroquinolones, aminoglycosides, and β-lactams were identified. Besides potential novel biomarkers with a direct correlation to resistance, global patterns of phenotype-associated gene expression and sequence variations were identified by predictive machine learning approaches. Our research serves to establish genotype-based molecular diagnostic tools for the identification of the current resistance profiles of bacterial pathogens and paves the way for faster diagnostics for more efficient, targeted treatment strategies to also mitigate the future potential for resistance evolution. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Transcriptome Profiling of Antimicrobial Resistance in Pseudomonas aeruginosa

PubMed Central

Khaledi, Ariane; Schniederjans, Monika; Pohl, Sarah; Rainer, Roman; Bodenhofer, Ulrich; Xia, Boyang; Klawonn, Frank; Bruchmann, Sebastian; Preusse, Matthias; Eckweiler, Denitsa; Dötsch, Andreas

2016-01-01

Emerging resistance to antimicrobials and the lack of new antibiotic drug candidates underscore the need for optimization of current diagnostics and therapies to diminish the evolution and spread of multidrug resistance. As the antibiotic resistance status of a bacterial pathogen is defined by its genome, resistance profiling by applying next-generation sequencing (NGS) technologies may in the future accomplish pathogen identification, prompt initiation of targeted individualized treatment, and the implementation of optimized infection control measures. In this study, qualitative RNA sequencing was used to identify key genetic determinants of antibiotic resistance in 135 clinical Pseudomonas aeruginosa isolates from diverse geographic and infection site origins. By applying transcriptome-wide association studies, adaptive variations associated with resistance to the antibiotic classes fluoroquinolones, aminoglycosides, and β-lactams were identified. Besides potential novel biomarkers with a direct correlation to resistance, global patterns of phenotype-associated gene expression and sequence variations were identified by predictive machine learning approaches. Our research serves to establish genotype-based molecular diagnostic tools for the identification of the current resistance profiles of bacterial pathogens and paves the way for faster diagnostics for more efficient, targeted treatment strategies to also mitigate the future potential for resistance evolution. PMID:27216077

Assessing the Knowledge, Attitudes and Behaviors of Human and Animal Health Students towards Antibiotic Use and Resistance: A Pilot Cross-Sectional Study in the UK

PubMed Central

Hills, Holly; Seitz, Lara-Turiya; Perry, Alex

2018-01-01

The Global Action Plan on Antimicrobial Resistance highlights the importance of training all healthcare professionals. No study has assessed patterns of students’ knowledge, attitudes and practices concerning antibiotic use simultaneously across different healthcare course types. We conducted a cross-sectional multi-center survey among UK students. The survey was advertised through local survey coordinators at 25 universities. The online survey was accessible from 10th October to 17th November 2016 (before European Antibiotic Awareness Day). A total of 255 students from 25 universities participated, including students on medicine, pharmacy, nursing, physician associate, dentistry and veterinary medicine courses. Antibiotic resistance was considered to be a more important global challenge than climate change, obesity or food security (p < 0.001). Most students (95%) believed that antibiotic resistance will be a problem for their future practice, but fewer (69%) thought that the antibiotics they will prescribe, administer or dispense will contribute to the problem. A fifth of students felt they had sufficient knowledge of antibiotic use for their future work. Our exploratory study suggests that UK human and animal healthcare students are aware of the importance of antibiotic resistance, but many still have certain misconceptions. Campaigns and improved educational efforts applying behavioral insights methodology could address these. PMID:29385687

Antimicrobial Resistance Expressed by Neisseria gonorrhoeae: A Major Global Public Health Problem in the 21st Century.

PubMed

Unemo, Magnus; Del Rio, Carlos; Shafer, William M

2016-06-01

Neisseria gonorrhoeae is a strictly human pathogen that is typically transmitted by sexual contact. The associated disease gonorrhea has plagued humankind for thousands of years, with a current estimated incidence of 78 million cases per year. Advances in antimicrobial discovery in the 1920s and 1930s leading to the discovery of sulfonamides and penicillin begun the era of effective antimicrobial treatment of gonorrhea. Unfortunately, the gonococcus developed decreased susceptibility or even resistance to these initially employed antibiotics, a trend that continued over subsequent decades with each new antibiotic that was brought into clinical practice. As this pattern of resistance has continued into the 21st century, there is now reason for great concern, especially in an era when few new antibiotics have prospects for use as treatment of gonorrhea. Here, we review the history of gonorrhea treatment regimens and gonococcal resistance to antibiotics, the mechanisms of resistance, resistance monitoring schemes that exist in different international settings, global responses to the challenge of resistance, and prospects for future treatment regimens in the 21st century.

Shattering a myth - Whooping cough susceptible to antibiotics.

PubMed

Syed, Muhammad Ali; Jamil, Bushra; Bokhari, Habib

2016-05-01

Bordetella parapertussis is the causative agent of a milder form of pertussis or whooping cough. Little is reported about the antibiotic resistance patterns and mechanism of drug resistance of Bordetella parapertussis. The objective of this study has been to investigate antimicrobial resistance, distribution of integrons and presence of gene cassettes to quinolones (qnr) and sulfonamides (sul) among B. parapertussis strains' isolated from Pakistan. Thirty-five (35) samples were collected from various hospitals of Pakistan from children (median age 3 years) with pertussis-like symptoms, all were tested and confirmed to be B. Parapertussis. Resistance profile of Ampicillin, Cephalexin, Sulphamethoxazole, Chloramphenicol, Ofloxacin, Nalidixic acid, Gentamycin and Erythromycin were investigated through all samples. Majority of the isolates were found to be resistant to the afore-mentioned antibiotics except erythromycin. All isolates were resistant to quinolones phenotypically, but qnr genes were detected in only 25.7% (9/35) of isolates. On the other hand, 71.4% (25/35) isolates were resistant to sulfonamides phenotypically. From these 71% strains showing phenotypical resistance, 96% (24/25) were found to possess sul genes. Only two isolates were carrying class 1 integrons, which also harbored sul gene and qnr gene cassettes. It can be safely concluded that the phenotypic resistance patterns seemed mostly independent of presence of integrons. However, interestingly both integrons harboring strains were resistant to quinolones and sulfonamides and also possessed qnr and sul genes.

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

PubMed

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

2016-03-01

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

MICROBIAL PROFILE AND ANTIBIOTIC SUSCEPTIBILITY PATTERNS OF PATHOGENS CAUSING VENTILATOR- ASSOCIATED PNEUMONIA AT INTENSIVE CARE UNIT, SESTRE MILOSRDNICE UNIVERSITY HOSPITAL CENTER, ZAGREB, CROATIA.

PubMed

Turković, Tihana Magdić; Grginić, Ana Gverić; Cucujić, Branka Đuras; Gašpar, Božena; Širanović, Mladen; Perić, Mladen

2015-06-01

Ventilator-associated pneumonia (VAP) is very common in many intensive care Units, but there are still many uncertainties about VAP, especially about the choice of initial empiric antibiotics. The incidence of specific pathogens with different susceptibility patterns causing VAP varies from hospital to hospital. This is the reason why empiric initial antibiotic treatment for VAP should be based not only on general guidelines (that recommend therapy according to the presence of risk factors for multidrug-resistant bacteria), but also on up-to-date information on local epidemiology. The aim of this study was to determine the microbial profile of pathogens causing VAP and their antibiotic susceptibility patterns. The study was conducted in the 15-bed surgical and neurosurgical Intensive Care Unit, Department of Anesthesiology and Intensive Care, Sestre milosrdnice University Hospital Center, Zagreb, Croatia. Retrospective data were collected from September 2009 to March 2013. All patients that developed VAP during the study period were eligible for the study. According to study results, the incidence of VAP was 29.4%. The most commonly isolated bacterium was Staphylococcus aureus (21.1%), followed by Pseudomonas aeruginosa (19.0%) and Acinetobacter species (13.6%). All Staphylococcus aureus isolates were susceptible to vancomycin and linezolid. Pseudomonas aeruginosa showed 100% susceptibility to cefepime and very high susceptibility to pip'eracillin-tazobactam (96%), ceftazidime (93%) and ciprofloxacin (89%). Ampicillin-sulbactam was highly effective for Acinetobacter species, showing resistance in only 8% of isolates. In conclusion, according to study data, appropriate empiric antibiotic therapy for patients with VAP without risk factors for multidrug-resistant bacteria is ceftriaxone and for patients with risk factors for multidrug-resistant bacteria ampicillin-sulbactam plus cefepime plus vancomycin or linezolid.

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

PubMed

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

2018-04-27

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

Antibiotic Resistances of Yogurt Starter Cultures Streptococcus thermophilus and Lactobacillus bulgaricus

PubMed Central

Sozzi, Tommaso; Smiley, Martin B.

1980-01-01

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

Methicillin resistant Staphylococcus aureus in Ethiopia: a meta-analysis.

PubMed

Eshetie, Setegn; Tarekegn, Fentahun; Moges, Feleke; Amsalu, Anteneh; Birhan, Wubet; Huruy, Kahsay

2016-11-21

The burden of methicillin resistant Staphylococcus aureus is a major public health concern worldwide; however the overall epidemiology of multidrug resistant strains is neither coordinated nor harmonized, particularly in developing countries including Ethiopia. Therefore, the aim of this meta-analysis was to assess the burden of methicillin resistant Staphylococcos aureus and its antibiotic resistance pattern in Ethiopia at large. PubMed, Google Scholar, and lancet databases were searched and a total of 20 studies have been selected for meta-analysis. Six authors have independently extracts data on the prevalence of methicillin resistant Staphylococcus aureus among clinical isolates of Staphylococcus aureus. Statistical analysis was achieved by using Open meta-analyst (version 3.13) and Comprehensive meta-analysis (version 3.3) softwares. The overall prevalence of methicillin resistant Staphylococcus aureus and its antibiotic resistance pattern were pooled by using the forest plot, table and figure with 95% CI. The pooled prevalence of methicillin resistant Staphylococcus aureus was 32.5% (95% CI, 24.1 to 40.9%). Moreover, methicillin resistant Staphylococcus aureus strains were found to be highly resistant to penicillin, ampicillin, erythromycin, and amoxicillin, with a pooled resistance ratio of 99.1, 98.1, 97.2 and 97.1%, respectively. On the other hand, comparably low levels of resistance ratio were noted to vancomycin, 5.3%. The overall burden of methicillin resistant Staphylococcus aureus is considerably high, besides these strains showed extreme resistance to penicillin, ampicillin, erythromycin and amoxicillin. In principle, appropriate use of antibiotics, applying safety precautions are the key to reduce the spread of multidrug resistant strains, methicillin resistant Staphylococcus aureus in particular.

Local audit: How tightly should we police antibiotic prescribing for urinary tract infection and how should we modify national policy?

PubMed

Brair, Amallia; Toozs-Hobson, Philip; Gray, Jim

2015-12-01

In 2010, our hospital, in line with National guidance, changed advice on antibiotic prescribing for UTI to reduce use of cephalosporins in favour of penicillins. We hypothesized that this change in policy would have no impact on the pattern of antibiotic resistance of the organisms causing UTI. Audit review of all urine samples sent to BWH from 2009 to 2013 and positive cultures showing Enterobacteriaceae were then tested for antibiotic susceptibility. There has been an increase in the resistance of both Co-amoxiclav and Ciprofloxacin since 2009. Co-amoxiclav and trimethoprim now have similar resistance rates. Ciprofloxacin resistance has risen fairly quickly in the last four years from 1% to 8%. Resistance to nitrofurantoin has remained low. Gentamicin resistance remained stable and very low, second best to meroponem. The results have been fed back to commissioners and internally and are being used as part of the guideline updating process. Hospital protocols for treating infections should be reviewed and updated based on accurate local data. These data should be used for formulating regional specific protocols. Our results suggest that meroponem and ciprofloxacin should be reserved for microbiologically proven resistance to other antibiotics. © The Author(s) 2015.

Bacterial Community Shift Drives Antibiotic Resistance Promotion during Drinking Water Chlorination.

PubMed

Jia, Shuyu; Shi, Peng; Hu, Qing; Li, Bing; Zhang, Tong; Zhang, Xu-Xiang

2015-10-20

For comprehensive insights into the effects of chlorination, a widely used disinfection technology, on bacterial community and antibiotic resistome in drinking water, this study applied high-throughput sequencing and metagenomic approaches to investigate the changing patterns of antibiotic resistance genes (ARGs) and bacterial community in a drinking water treatment and distribution system. At genus level, chlorination could effectively remove Methylophilus, Methylotenera, Limnobacter, and Polynucleobacter, while increase the relative abundance of Pseudomonas, Acidovorax, Sphingomonas, Pleomonas, and Undibacterium in the drinking water. A total of 151 ARGs within 15 types were detectable in the drinking water, and chlorination evidently increased their total relative abundance while reduced their diversity in the opportunistic bacteria (p < 0.05). Residual chlorine was identified as the key contributing factor driving the bacterial community shift and resistome alteration. As the dominant persistent ARGs in the treatment and distribution system, multidrug resistance genes (mainly encoding resistance-nodulation-cell division transportation system) and bacitracin resistance gene bacA were mainly carried by chlorine-resistant bacteria Pseudomonas and Acidovorax, which mainly contributed to the ARGs abundance increase. The strong correlation between bacterial community shift and antibiotic resistome alteration observed in this study may shed new light on the mechanism behind the chlorination effects on antibiotic resistance.

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

PubMed

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

2016-11-24

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

Genetic diversity of Streptococcus suis isolated from three pig farms of China obtained by acquiring antibiotic resistance genes.

PubMed

Huang, Jinhu; Shang, Kexin; Kashif, Jam; Wang, Liping

2015-05-01

Acquiring antibiotic resistance genes may change an organism's genetic characteristics and the effect of antibiotics, resulting in a rapid transmission of microbial pathogens. The objectives of this experiment were to identify the features of Streptococcus suis (S. suis) isolated from three pig farms in China which are geographically isolated. Among the isolates, 56.52% were sequence type 7 (ST7), followed by ST1 (26.09%), indicating that ST7 prevails in China, as revealed by multi-locus sequence typing (MLST). Statistical analysis indicated an association between geography, sequence types and antibiotic resistance genotypes. 66.67% of the isolates in Sichuan province presented a (ermB(-) + mefA(-) + tetO(-) + tetM(-)) + ST7 type. The tetM(+) +ST7 type was the most prevalent in Jiangsu province, whereas the strains from Hebei province had a phenotype ermB(+) +tetO(+) +ST1 (63.64%). Pulsed-field gel electrophoresis (PGFE) pattern A2 with 100% similarity reflected the clonal dissemination between Sichuan and Jiangsu provinces. Strains carrying or not carrying antibiotic resistance genes presented different PFGE patterns in Hebei province. ST7 is widespread in many regions of China and a clonal dissemination occurred between Sichuan and Jiangsu provinces in diseased pigs. However, ST1 strains with macrolide and tetracycline resistance (ermB(+) +tetO(+) +ST1) isolated from a farm in Hebei province demonstrated that the genetic diversity was contributed by horizontal acquiring of ermB and tetO carrying elements. © 2014 Society of Chemical Industry.

Antibiotic resistance of Helicobacter pylori in Chinese children: A multicenter retrospective study over 7 years.

PubMed

Li, Lan; Ke, Yini; Yu, Chaohui; Li, Guogang; Yang, Ningmin; Zhang, Jianzhong; Li, Youming

2017-06-01

To determine the prevalence of resistance to metronidazole, clarithromycin, levofloxacin, amoxicillin, and furazolidone in Helicobacter pylori isolated from Chinese children. This multicenter retrospective study was conducted from January 2009 to December 2015. A total of 1746 isolates of H. pylori were collected from nine areas of Zhejiang province in the southeast coastal region of China. H. pylori strains were examined for antibiotics susceptibility by agar dilution method. The resistance rates were 75.20% for metronidazole, 16.38% for clarithromycin, 6.70% for levofloxacin, 0.06% for amoxicillin, and 0.06% for furazolidone. The pattern of H. pylori antibiotic resistance demonstrated no significant changes in the rates of resistance to clarithromycin, amoxicillin, furazolidone, and metronidazole over 7 years. A significant trend of increasing resistance to metronidazole was observed as children aged, but a downward trend in clarithromycin resistance was observed as children aged. No difference in the resistance to other antibiotics was observed among different age groups. Also, there was no significant difference between male and female subjects in rates of resistance to these five types of antibiotics. The predominant dual resistance to metronidazole and clarithromycin was presented in 10.65% of the isolates. The resistance rates of H. pylori in children from southeast coastal region of China were very high to metronidazole, moderate to clarithromycin and levofloxacin, and low to amoxicillin and furazolidone. It is important to continue monitoring the resistance profiles of H. pylori isolated in this region. © 2017 John Wiley & Sons Ltd.

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.

Plasmid curing analysis of antibiotic resistance in beta-lactamase producing Staphylococci from wounds and burns patients.

PubMed

Ojo, S K S; Sargin, B O; Esumeh, F I

2014-01-01

Hospitals worldwide are facing unprecedented crisis due to increasingly rapid emergence and dissemination of antimicrobial resistant staphylococci in wounds and burns and its environs via plasmid mediation. This study was conducted to evaluate the plasmid-mediated or chromosomal-mediated resistance in staphylococci. One hundred clinical swabs from wounds and burns patients were demonstrated for presence of staphylococci using mannitol salt agar. Various biochemical, DNase and beta-lactamase test was carried out and the plasmid curing assay was demonstrated using 0.1 mg mL(-1) acridine orange on antibiotic resistant isolates. The results revealed S. aureus (47) and coagulase negative staphylococci (CoNS) (6). beta-lactamase producing species of S. aureus were 14 and CoNS was 1. Most isolates showed high resistance pattern to gentamicin, ciprofloxacin, norfloxacin, rifampicin, chloramphenicol, ampiclox and others. The antibiotic resistance isolates were highly indicative ofplasmid-borne and few are chromosomal-borne after the plasmid curing analysis. The plasmid-mediated resistance observed among various antibiotics poses difficulty in treatment for clinicians. This high plasmid-mediated resistance among the isolates and from other studies calls for an urgent surveillance and epidemiological studies to infection control.

Comparison of ubiquitous antibiotic-resistant Enterobacteriaceae populations isolated from wastewaters, surface waters and drinking waters.

PubMed

Figueira, Vânia; Serra, Elizabete A; Vaz-Moreira, Ivone; Brandão, Teresa R S; Manaia, Célia M

2012-03-01

This study aimed at assessing the role of ubiquitous (non-Escherichia coli) Enterobacteriaceae in the dissemination of antimicrobial resistance through the urban water cycle. Enterobacteriaceae isolated from a municipal wastewater treatment plant (111 isolates), urban water streams (33 isolates) and drinking water (123 isolates) were compared in terms of: (i) genera distribution, (ii) resistance to 12 antibiotics, and (iii) class 1 and class 2 integrons. The predominant bacterial genera were the same in the different types of water, although with a distinct pattern of species. The most prevalent resistance phenotypes were observed for amoxicillin, ticarcillin, cephalothin and sulphamethoxazole (24-59% in the three types of water). No resistance against ceftazidime or meropenem was observed. Resistance to cephalothin, amoxicillin and sulphamethoxazole was significantly more prevalent in drinking water, water streams and wastewater, respectively, than in the other types of water. It was possible to recognize antibiotic-resistance associations, namely for the pairs streptomycin-tetracycline (positive) and ticarcillin-cephalotin (negative). Class 1 and/or class 2 integrons with similar gene cassettes were detected in the three types of water. This study demonstrated that Enterobacteriaceae are important vehicles of antibiotic resistance, namely in drinking water.

Predictable Phenotypes of Antibiotic Resistance Mutations.

PubMed

Knopp, M; Andersson, D I

2018-05-15

Antibiotic-resistant bacteria represent a major threat to our ability to treat bacterial infections. Two factors that determine the evolutionary success of antibiotic resistance mutations are their impact on resistance level and the fitness cost. Recent studies suggest that resistance mutations commonly show epistatic interactions, which would complicate predictions of their stability in bacterial populations. We analyzed 13 different chromosomal resistance mutations and 10 host strains of Salmonella enterica and Escherichia coli to address two main questions. (i) Are there epistatic interactions between different chromosomal resistance mutations? (ii) How does the strain background and genetic distance influence the effect of chromosomal resistance mutations on resistance and fitness? Our results show that the effects of combined resistance mutations on resistance and fitness are largely predictable and that epistasis remains rare even when up to four mutations were combined. Furthermore, a majority of the mutations, especially target alteration mutations, demonstrate strain-independent phenotypes across different species. This study extends our understanding of epistasis among resistance mutations and shows that interactions between different resistance mutations are often predictable from the characteristics of the individual mutations. IMPORTANCE The spread of antibiotic-resistant bacteria imposes an urgent threat to public health. The ability to forecast the evolutionary success of resistant mutants would help to combat dissemination of antibiotic resistance. Previous studies have shown that the phenotypic effects (fitness and resistance level) of resistance mutations can vary substantially depending on the genetic context in which they occur. We conducted a broad screen using many different resistance mutations and host strains to identify potential epistatic interactions between various types of resistance mutations and to determine the effect of strain background on resistance phenotypes. Combinations of several different mutations showed a large amount of phenotypic predictability, and the majority of the mutations displayed strain-independent phenotypes. However, we also identified a few outliers from these patterns, illustrating that the choice of host organism can be critically important when studying antibiotic resistance mutations. Copyright © 2018 Knopp and Andersson.

Invasive Bacterial Pathogens and their Antibiotic Susceptibility Patterns in Jimma University Specialized Hospital, Jimma, Southwest Ethiopia.

PubMed

Zenebe, Tizazu; Kannan, Subbaram; Yilma, Daniel; Beyene, Getenet

2011-03-01

Presence of microorganisms in the circulating blood whether continuously or intermittently is a threat to every organ in the body. Approximately 200,000 cases of bacteraemia occur annually with mortality rates ranging from 20-50%. Early diagnosis and appropriate treatment of these infections can make the difference between life and death. The aim of the present study was to determine the bacterial flora of the blood stream infections and their antibiotic susceptibility pattern. A cross sectional study was conducted on 260 adult febrile patients in Jimma University Specialized Hospital from 27 October 2009 to 26 March 2010. The positive blood cultures were examined and the organisms were identified as per standard procedures. Antimicrobial testing was performed for all isolates by disk diffusion techniques, according to Clinical Laboratory Standards Institute guide lines. The data was analyzed using SPSS for windows version 16 and Microsoft Office Excel. From the total of two hundred sixty blood specimens only 23(8.8%) were positive to seven different types of bacteria. The isolated bacteria were: Coagulase negative staphylococci 6(26.1%), S. aureus 5 (21.7%), S. pyogens 3 (13.0%), E. coli 4(17.4%), K. pneumoniae 3(13.0%), Salmonella spp. 1(4.3%), and Citrobacter spp. 1(4.3%). The isolates showed high rates of resistance to most antibiotics tested. The range of resistance for gram positive bacteria were 0% to 85.7%, and for gram negative from 0% to 100%. None of the isolates were resistance to ciprofloxacin and ceftriaxone. Our study result showed the presence of invasive bacterial pathogens with high rate of resistance to most commonly used antibiotics used to treat bacterial infections. Therefore, timely investigation of bacterial flora of the blood stream infections and monitoring of their antibiotic resistance pattern plays an important role in reduction of the incidence of blood stream infections.

Nosocomial infections and antibiotic resistance pattern in open-heart surgery patients at Imam Ali Hospital in Kermanshah, Iran.

PubMed

Heydarpour, Fatemeh; Rahmani, Youssef; Heydarpour, Behzad; Asadmobini, Atefeh

2017-01-01

Background: Patients undergoing open heart surgery have a relatively high risk of acquiring nosocomial infections. The development of antibiotic-resistant infections is associated with prolonged hospital stays and mortalities. Objectives: The present study was conducted to investigate nosocomial infections and the antibiotic resistance pattern in bacteria causing these infections in open heart surgery patients at Imam Ali Hospital in Kermanshah in the west of Iran over a 4-year period from March 2011 to March 2014. Materials and methods: The present cross-sectional study was conducted on 135 cases of nosocomial infection among open heart surgery patients. The demographic characteristics and the risk factors of each case of infection were recorded. The antibiotic susceptibility test was carried out using the Minimum Inhibitory Concentration (MIC) method based on the Clinical and Laboratory Standards Institute (CLSI) protocol. The data collected were then analyzed in SPSS-16. Results: Out of the 6,000 patients who underwent open heart surgery during this 4-year period at the selected hospital, nosocomial infections developed in 135 patients (2.25%), 59.3% of whom were female and 40.7% male. Surgery site infection (SSI), pneumonia (PNEU), urinary tract infection (UTI) and blood stream infection (BSI) affected 52.6%, 37%, 9.6% and 0.8% of the cases, respectively. E.coli , Klebsiella spp. and S. aureus were the most common bacteria causing the nosocomial infections. E. coli was most frequently resistant to imipenem (23.3%) Klebsiella spp. to gentamicin (38.5%) S. aureus to co-trimoxazole (54.2%). Conclusion: SSI had a high prevalence in this study. Further studies should therefore be conducted to examine the risk factors associated with SSI in open heart surgery. Various studies have shown that antibiotic resistance patterns are different in different regions. Finding a definitive treatment therefore requires an antibiogram.

Antibiotic resistance and molecular characterization of probiotic and clinical Lactobacillus strains in relation to safety aspects of probiotics.

PubMed

Klein, Günter

2011-02-01

The evaluation of the safety of probiotic strains includes the exclusion of antibiotic resistance of clinical importance. Ninety-two strains from the genus Lactobacillus isolated from probiotics, food, and clinical sources were included in the investigation. Species tested were the L. acidophilus group, L. casei group, L. reuteri/fermentum group, and L. sakei/curvatus group. Cell and colony morphology, fermentation patterns, and growth characteristics as well as soluble whole cell proteins were analyzed. Antibiotic resistance against clinically important agents was determined by broth dilution tests. The vanA and tet genes were confirmed. Resistances occurred mainly against gentamicin, ciprofloxacin, clindamycin, sulfonamides, and, in some cases, glycopeptides. The natural glycopeptide resistance within the L. casei group and L. reuteri appears to be not of clinical relevance, as there was no vanA gene present. Therefore, the transfer of this resistance is very unlikely. Tet-(A), -(B), -(C), -(M), or -(O) gene could not be detected. The protein fingerprinting within the L. casei group proved that L. rhamnosus strains of clinical origin clustered together with probiotic strains. For safety evaluations resistance patterns of a broad range of strains are a useful criterion together with the exclusion of known resistance genes (like the vanA gene) and can be used for decision making on the safety of probiotics, both by authorization bodies and manufacturers.

[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.

Biofilm formation, antibiotic susceptibility and RAPD genotypes in Pseudomonas aeruginosa clinical strains isolated from single centre intensive care unit patients.

PubMed

Vaněrková, Martina; Mališová, Barbora; Kotásková, Iva; Holá, Veronika; Růžička, Filip; Freiberger, Tomáš

2017-11-01

The aim of this study was to analyse genotypes, antimicrobial susceptibility patterns and serotypes in Pseudomonas aeruginosa clinical strains, including the clonal dissemination of particular strains throughout various intensive care units in one medical centre. Using random amplified polymorphic DNA (RAPD-PCR) and P. aeruginosa antisera, 22 different genotypes and 8 serotypes were defined among 103 isolates from 48 patients. No direct association between P. aeruginosa strain genotypes and serotypes was observed. RAPD typing in strains with the same serotype revealed different genotypes and, on the contrary, most strains with a different serotype displayed the same amplification pattern. The resulting banding patterns showed a high degree of genetic heterogeneity among all isolates from the patients examined, suggesting a non-clonal relationship between isolates from these patients. A higher degree of antibiotic resistance and stronger biofilm production in common genotypes compared to rare ones and genetic homogeneity of the most resistant strains indicated the role of antibiotic pressure in acquiring resistant and more virulent strains in our hospital. In conclusion, genetic characterisation of P. aeruginosa strains using RAPD method was shown to be more accurate in epidemiological analyses than phenotyping.

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.

Antimicrobial resistance determinant microarray for analysis of multi-drug resistant isolates

NASA Astrophysics Data System (ADS)

Taitt, Chris Rowe; Leski, Tomasz; Stenger, David; Vora, Gary J.; House, Brent; Nicklasson, Matilda; Pimentel, Guillermo; Zurawski, Daniel V.; Kirkup, Benjamin C.; Craft, David; Waterman, Paige E.; Lesho, Emil P.; Bangurae, Umaru; Ansumana, Rashid

2012-06-01

The prevalence of multidrug-resistant infections in personnel wounded in Iraq and Afghanistan has made it challenging for physicians to choose effective therapeutics in a timely fashion. To address the challenge of identifying the potential for drug resistance, we have developed the Antimicrobial Resistance Determinant Microarray (ARDM) to provide DNAbased analysis for over 250 resistance genes covering 12 classes of antibiotics. Over 70 drug-resistant bacteria from different geographic regions have been analyzed on ARDM, with significant differences in patterns of resistance identified: genes for resistance to sulfonamides, trimethoprim, chloramphenicol, rifampin, and macrolide-lincosamidesulfonamide drugs were more frequently identified in isolates from sources in Iraq/Afghanistan. Of particular concern was the presence of genes responsible for resistance to many of the last-resort antibiotics used to treat war traumaassociated infections.

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

PubMed Central

Saravanan, Revathy; Raveendaran, Vinod

2013-01-01

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

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).

Protocol: a 'One health' two year follow-up, mixed methods study on antibiotic resistance, focusing children under 5 and their environment in rural India.

PubMed

Stålsby Lundborg, Cecilia; Diwan, Vishal; Pathak, Ashish; Purohit, Manju R; Shah, Harshada; Sharma, Megha; Mahadik, Vijay K; Tamhankar, Ashok J

2015-12-30

Antibiotic resistance has been referred to as 'the greatest malice of the 21st century' and a global action plan was adopted by the World Health Assembly in 2015. There is a wealth of independent studies regarding antibiotics and resistant bacteria in humans, animals and their environment, however, integrated studies are lacking, particularly ones that simultaneously also take into consideration the health related behaviour of participants and healthcare providers. Such, 'One health' studies are difficult to implement, because of the complex teamwork that they entail. This paper describes the protocol of a study that investigates 'One health' issues regarding antibiotic use and antibiotic resistance in children and their environment in Indian villages. Both quantitative and qualitative studies are planned for a cohort of children, from 6 villages, and their surrounding environment. Repeated or continues data collection is planned over 2 years for quantitative studies. Qualitative studies will be conducted once. Studies include parents' health seeking behavior for their children (1-3 years of age at the onset), prescribing pattern of formal and informal healthcare providers, analysis of phenotypic antibiotic resistance of Escherichia coli from samples of stool from children and village animals, household drinking water, village source water and waste water, and investigation on molecular mechanisms governing resistance. Analysis of interrelationship of these with each other will also be done as basis for future interventions. Ethics approval has been obtained from the Institutional Ethics Committee R.D. Gardi Medical College, Ujjain, India (No: 2013/07/17-311). The findings of the study presented in this protocol will add to our knowledge about the multi-factorial nature of causes governing antibiotic use and antibiotic resistance from a 'One health' perspective. Our study will be the first of its kind addressing antibiotic use and resistance issues related to children in a One-health approach, particularly for rural India.

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.

Effect of antibiotic stewardship on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infection: a systematic review and meta-analysis.

PubMed

Baur, David; Gladstone, Beryl Primrose; Burkert, Francesco; Carrara, Elena; Foschi, Federico; Döbele, Stefanie; Tacconelli, Evelina

2017-09-01

Antibiotic stewardship programmes have been shown to reduce antibiotic use and hospital costs. We aimed to evaluate evidence of the effect of antibiotic stewardship on the incidence of infections and colonisation with antibiotic-resistant bacteria. For this systematic review and meta-analysis, we searched PubMed, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Web of Science for studies published from Jan 1, 1960, to May 31, 2016, that analysed the effect of antibiotic stewardship programmes on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infections in hospital inpatients. Two authors independently assessed the eligibility of trials and extracted data. Studies involving long-term care facilities were excluded. The main outcomes were incidence ratios (IRs) of target infections and colonisation per 1000 patient-days before and after implementation of antibiotic stewardship. Meta-analyses were done with random-effect models and heterogeneity was calculated with the I 2 method. We included 32 studies in the meta-analysis, comprising 9 056 241 patient-days and 159 estimates of IRs. Antibiotic stewardship programmes reduced the incidence of infections and colonisation with multidrug-resistant Gram-negative bacteria (51% reduction; IR 0·49, 95% CI 0·35-0·68; p<0·0001), extended-spectrum β-lactamase-producing Gram-negative bacteria (48%; 0·52, 0·27-0·98; p=0·0428), and meticillin-resistant Staphylococcus aureus (37%; 0·63, 0·45-0·88; p=0·0065), as well as the incidence of C difficile infections (32%; 0·68, 0·53-0·88; p=0·0029). Antibiotic stewardship programmes were more effective when implemented with infection control measures (IR 0·69, 0·54-0·88; p=0·0030), especially hand-hygiene interventions (0·34, 0·21-0·54; p<0·0001), than when implemented alone. Antibiotic stewardship did not affect the IRs of vancomycin-resistant enterococci and quinolone-resistant and aminoglycoside-resistant Gram-negative bacteria. Significant heterogeneity between studies was detected, which was partly explained by the type of interventions and co-resistance patterns of the target bacteria. Antibiotic stewardship programmes significantly reduce the incidence of infections and colonisation with antibiotic-resistant bacteria and C difficile infections in hospital inpatients. These results provide stakeholders and policy makers with evidence for implementation of antibiotic stewardship interventions to reduce the burden of infections from antibiotic-resistant bacteria. German Center for Infection Research. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anthropogenic antibiotic resistance genes mobilization to the polar regions.

PubMed

Hernández, Jorge; González-Acuña, Daniel

2016-01-01

Anthropogenic influences in the southern polar region have been rare, but lately microorganisms associated with humans have reached Antarctica, possibly from military bases, fishing boats, scientific expeditions, and/or ship-borne tourism. Studies of seawater in areas of human intervention and proximal to fresh penguin feces revealed the presence of Escherichia coli strains least resistant to antibiotics in penguins, whereas E. coli from seawater elsewhere showed resistance to one or more of the following antibiotics: ampicillin, tetracycline, streptomycin, and trim-sulfa. In seawater samples, bacteria were found carrying extended-spectrum β-lactamase (ESBL)-type CTX-M genes in which multilocus sequencing typing (MLST) showed different sequence types (STs), previously reported in humans. In the Arctic, on the contrary, people have been present for a long time, and the presence of antibiotic resistance genes (ARGs) appears to be much more wide-spread than was previously reported. Studies of E coli from Arctic birds (Bering Strait) revealed reduced susceptibility to antibiotics, but one globally spreading clone of E. coli genotype O25b-ST131, carrying genes of ESBL-type CTX-M, was identified. In the few years between sample collections in the same area, differences in resistance pattern were observed, with E. coli from birds showing resistance to a maximum of five different antibiotics. Presence of resistance-type ESBLs (TEM, SHV, and CTX-M) in E. coli and Klebsiella pneumoniae was also confirmed by specified PCR methods. MLST revealed that those bacteria carried STs that connect them to previously described strains in humans. In conclusion, bacteria previously related to humans could be found in relatively pristine environments, and presently human-associated, antibiotic-resistant bacteria have reached a high global level of distribution that they are now found even in the polar regions.

Etiology of early onset septicemia among neonates at the University College Hospital, Ibadan, Nigeria.

PubMed

Akindolire, Abimbola Ellen; Tongo, Olukemi; Dada-Adegbola, Hannah; Akinyinka, Olusegun

2016-12-30

Neonatal septicemia remains a major cause of newborn deaths in developing countries. Its burden is further compounded by the emergence of multidrug-resistant pathogens, which is related to a lack of antibiotic protocols resulting in unrestricted use of antibiotics. The absence of reliable antibiotic sensitivity testing makes the formulation of antibiotic guidelines and judicious use of antibiotics difficult. This study sought to identify the current bacterial agents associated with early onset septicemia (EOS; age <72 hours) and their antibiotic susceptibility patterns among neonates at the University College Hospital, Ibadan, Nigeria. A total of 202 inborn and outborn neonates with risk factors for or clinical features of septicemia in the first 72 hours of life had samples for blood cultures and antibiotic sensitivity patterns taken prior to treatment. Of the subjects, 95 (47.0%) were inborn and 107 (53.0%) outborn, with a M:F ratio of 1.3:1; 12.5% were culture positive, and the prevalence of EOS was 8.8/1,000 live births. The isolates were Staphylococcus aureus (52%), 30.7% of which were methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae (12%), Enterobacter aerogenes (8%), Enterococcus spp. (8%), Eschericia coli (4%), and other Gram-negatives (12%). All the isolates except Staphylococcus aureus were susceptible to ampicillin, ampicillin/sulbactam, amikacin, gentamicin, and third-generation cephalosporins. All MRSA were sensitive to amikacin, ciprofloxacin, and chloramphenicol, while all methicillin-sensitive Staphylococcus aureus were sensitive to ampicillin/sulbactam. Staphylococcus aureus was the commonest cause of EOS in our setting, with 30.7% of the Staphylococcus aureus isolates being MRSA. Only MRSA demonstrated multidrug resistance.

Metagenomic analysis of antibiotic resistance genes in coastal industrial mariculture systems.

PubMed

Wang, Jian-Hua; Lu, Jian; Zhang, Yu-Xuan; Wu, Jun; Luo, Yongming; Liu, Hao

2018-04-01

The overuse of antibiotics has posed a propagation of antibiotic resistance genes (ARGs) in aquaculture systems. This study firstly explored the ARGs profiles of the typical mariculture farms including conventional and recirculating systems using metagenomics approach. Fifty ARGs subtypes belonging to 21 ARGs types were identified, showing the wide-spectrum profiles of ARGs in the coastal industrial mariculture systems. ARGs with multiple antibiotics resistance have emerged in the mariculure systems. The co-occurrence pattern between ARGs and microbial taxa showed that Proteobacteria and Bacteroidetes were potential dominant hosts of ARGs in the industrial mariculture systems. Typical nitrifying bacteria such as Nitrospinae in mariculture systems also carried with some resistance genes. Relative abundance of ARGs in fish ponds and wastewater treatment units was relatively high. The investigation showed that industrial mariculture systems were important ARGs reservoirs in coastal area, indicating the critical role of recirculating systems in the terms of ARGs pollution control. Copyright © 2018 Elsevier Ltd. All rights reserved.

Antibiotics prescription in Nigerian dental healthcare services.

PubMed

Azodo, C C; Ojehanon, P I

2014-09-01

Inappropriate antibiotics prescription in dental healthcare delivery that may result in the emergence of antibiotic-resistant bacteria, is a worldwide concern. The objective of the study was to determine the antibiotics knowledge and prescription patterns among dentists in Nigeria. A total of 160 questionnaires were distributed to dentists attending continuing education courses organized by two organizations in Southern and Northern parts of Nigeria. Data analysis was done using SPSS version 17.0. A total of 146 questionnaires were returned, properly filled, out of 160 questionnaires, giving an overall response rate 91.3%. The clinical factors predominantly influenced the choice of therapeutic antibiotics among the respondents. In this study, the most commonly prescribed antibiotics among the respondents was a combination of amoxicillin and metronidazole. Of the respondents, 136 (93.2%) of them considered antibiotic resistance as a major problem in Nigeria and 102 (69.9%) have experienced antibiotics resistance in dental practice. The major reported conditions for prophylactic antibiotics among the respondents were diabetic mellitus, HIV/AIDS, history of rheumatic fever, other heart anomalies presenting with heart murmur and presence of prosthetic hip. The knowledge of adverse effects of antibiotics was greatest for tooth discoloration which is related to tetracycline. Data from this study revealed the most commonly prescribed antibiotics as a combination of amoxicillin and metronidazole. There existed gaps in prophylactic antibiotic prescription, consideration in the choice of therapeutic antibiotics and knowledge of adverse effects of antibiotics among the studied dentists.

Ten key points for the appropriate use of antibiotics in hospitalised patients: a consensus from the Antimicrobial Stewardship and Resistance Working Groups of the International Society of Chemotherapy.

PubMed

Levy Hara, Gabriel; Kanj, Souha S; Pagani, Leonardo; Abbo, Lilian; Endimiani, Andrea; Wertheim, Heiman F L; Amábile-Cuevas, Carlos; Tattevin, Pierre; Mehtar, Shaheen; Lopes Cardoso, Fernando; Unal, Serhat; Gould, Ian

2016-09-01

The Antibiotic Stewardship and Resistance Working Groups of the International Society for Chemotherapy propose ten key points for the appropriate use of antibiotics in hospital settings. (i) Get appropriate microbiological samples before antibiotic administration and carefully interpret the results: in the absence of clinical signs of infection, colonisation rarely requires antimicrobial treatment. (ii) Avoid the use of antibiotics to 'treat' fever: use them to treat infections, and investigate the root cause of fever prior to starting treatment. (iii) Start empirical antibiotic treatment after taking cultures, tailoring it to the site of infection, risk factors for multidrug-resistant bacteria, and the local microbiology and susceptibility patterns. (iv) Prescribe drugs at their optimal dosing and for an appropriate duration, adapted to each clinical situation and patient characteristics. (v) Use antibiotic combinations only where the current evidence suggests some benefit. (vi) When possible, avoid antibiotics with a higher likelihood of promoting drug resistance or hospital-acquired infections, or use them only as a last resort. (vii) Drain the infected foci quickly and remove all potentially or proven infected devices: control the infection source. (viii) Always try to de-escalate/streamline antibiotic treatment according to the clinical situation and the microbiological results. (ix) Stop unnecessarily prescribed antibiotics once the absence of infection is likely. And (x) Do not work alone: set up local teams with an infectious diseases specialist, clinical microbiologist, hospital pharmacist, infection control practitioner or hospital epidemiologist, and comply with hospital antibiotic policies and guidelines. Copyright © 2016. Published by Elsevier B.V.

[Urinary tract infections in the elderly].

PubMed

Becher, Klaus Friedrich; Klempien, Ingo; Wiedemann, Andreas

2015-10-01

Acute infection of the urinary tract is one of the most commonly encountered bacterial infections in the frail elderly population and is responsible for substantial morbidity and recurrent infections with antibiotic resistance. Although generally considered to be self-limiting without treatment or easily treated with a short antibiotic regime, urinary tract infections (UTIs) often have a dramatic history, associated with incomplete resolution and frequent recurrence. The biological complexity of the infections combined with a dramatic rise in antibiotic-resistant pathogens highlight the need for an anticipating strategy for therapy necessary for a rapid recovery. The first crucial step is the classification in asymptomatic bacteriuria or complicated pyelonephritis, on which the decision for the intensity of treatment and diagnostic effort is based. For the selection of empiric antibiotic therapy, knowledge about the predominant uropathogens as well as local resistance patterns is important. In this manner, most urinary tract infections in the elderly can be treated without greater expense.

Global antibiotic consumption 2000 to 2010: an analysis of national pharmaceutical sales data.

PubMed

Van Boeckel, Thomas P; Gandra, Sumanth; Ashok, Ashvin; Caudron, Quentin; Grenfell, Bryan T; Levin, Simon A; Laxminarayan, Ramanan

2014-08-01

Antibiotic drug consumption is a major driver of antibiotic resistance. Variations in antibiotic resistance across countries are attributable, in part, to different volumes and patterns for antibiotic consumption. We aimed to assess variations in consumption to assist monitoring of the rise of resistance and development of rational-use policies and to provide a baseline for future assessment. With use of sales data for retail and hospital pharmacies from the IMS Health MIDAS database, we reviewed trends for consumption of standard units of antibiotics between 2000 and 2010 for 71 countries. We used compound annual growth rates to assess temporal differences in consumption for each country and Fourier series and regression methods to assess seasonal differences in consumption in 63 of the countries. Between 2000 and 2010, consumption of antibiotic drugs increased by 36% (from 54 083 964 813 standard units to 73 620 748 816 standard units). Brazil, Russia, India, China, and South Africa accounted for 76% of this increase. In most countries, antibiotic consumption varied significantly with season. There was increased consumption of carbapenems (45%) and polymixins (13%), two last-resort classes of antibiotic drugs. The rise of antibiotic consumption and the increase in use of last-resort antibiotic drugs raises serious concerns for public health. Appropriate use of antibiotics in developing countries should be encouraged. However, to prevent a striking rise in resistance in low-income and middle-income countries with large populations and to preserve antibiotic efficacy worldwide, programmes that promote rational use through coordinated efforts by the international community should be a priority. US Department of Homeland Security, Bill & Melinda Gates Foundation, US National Institutes of Health, Princeton Grand Challenges Program. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preliminary survey of antibiotic-resistant fecal indicator bacteria and pathogenic Escherichia coli from river-water samples collected in Oakland County, Michigan, 2003

USGS Publications Warehouse

Fogarty, Lisa R.; Duris, Joseph W.; Aichele, Stephen S.

2005-01-01

A preliminary study was done in Oakland County, Michigan, to determine the concentration of fecal indicator bacteria (fecal coliform bacteria and enterococci), antibiotic resistance patterns of these two groups, and the presence of potentially pathogenic Escherichia coli (E. coli). For selected sites, specific members of these groups [E. coli, Enterococcus faecium (E. faecium) and Enterococcus faecalis (E. faecalis)] were isolated and tested for levels of resistance to specific antibiotics used to treat human infections by pathogens in these groups and for their potential to transfer these resistances. In addition, water samples from all sites were tested for indicators of potentially pathogenic E. coli by three assays: a growth-based assay for sorbitol-negative E. coli, an immunological assay for E. coli O157, and a molecular assay for three virulence and two serotype genes. Samples were also collected from two non-urbanized sites outside of Oakland County. Results from the urbanized Oakland County area were compared to those from these two non-urbanized sites. Fecal indicator bacteria concentrations exceeded State of Michigan recreational water-quality standards and (or) recommended U.S. Environmental Protection Agency (USEPA) standards in samples from all but two Oakland County sites. Multiple-antibiotic-resistant fecal coliform bacteria were found at all sites, including two reference sites from outside the county. Two sites (Stony Creek and Paint Creek) yielded fecal coliform isolates resistant to all tested antibiotics. Patterns indicative of extended-spectrum-β-lactamase (ESBL)- producing fecal coliform bacteria were found at eight sites in Oakland County and E. coli resistant to clinically significant antibiotics were recovered from the River Rouge, Clinton River, and Paint Creek. Vancomycin-resistant presumptive enterococci were found at six sites in Oakland County and were not found at the reference sites. Evidence of acquired antibiotic resistances was detected in bacteria from multiple sites in Oakland County but not detected in bacteria from the reference sites. Integrons capable of transferring resistance were detected in isolates from the River Rouge and Clinton River. E. faecium and E. faecalis identified in samples collected from Kearsley Creek and Evans Ditch were resistant to high levels of vancomycin and carried transferable genes responsible for resistance. Several sites in Oakland County had indicators of pathogenic E. coli in August and (or) September 2003. Two samples from the Clinton River in August tested positive for all three E. coli O157 tests. Both the August and September samples from one River Rouge site were positive for the immunological and molecular assay for E. coli O157. A combination of virulence genes commonly associated with human illness was detected at five sites in August and seven sites in September. Antibiotic-resistance profiles of clinical concern along with genes capable of transferring the resistance were found at several sites throughout Oakland County; samples from many of these sites also contained potentially pathogenic E. coli.

Metagenomic Frameworks for Monitoring Antibiotic Resistance in Aquatic Environments

PubMed Central

Port, Jesse A.; Cullen, Alison C.; Wallace, James C.; Smith, Marissa N.

2013-01-01

Background: High-throughput genomic technologies offer new approaches for environmental health monitoring, including metagenomic surveillance of antibiotic resistance determinants (ARDs). Although natural environments serve as reservoirs for antibiotic resistance genes that can be transferred to pathogenic and human commensal bacteria, monitoring of these determinants has been infrequent and incomplete. Furthermore, surveillance efforts have not been integrated into public health decision making. Objectives: We used a metagenomic epidemiology–based approach to develop an ARD index that quantifies antibiotic resistance potential, and we analyzed this index for common modal patterns across environmental samples. We also explored how metagenomic data such as this index could be conceptually framed within an early risk management context. Methods: We analyzed 25 published data sets from shotgun pyrosequencing projects. The samples consisted of microbial community DNA collected from marine and freshwater environments across a gradient of human impact. We used principal component analysis to identify index patterns across samples. Results: We observed significant differences in the overall index and index subcategory levels when comparing ecosystems more proximal versus distal to human impact. The selection of different sequence similarity thresholds strongly influenced the index measurements. Unique index subcategory modes distinguished the different metagenomes. Conclusions: Broad-scale screening of ARD potential using this index revealed utility for framing environmental health monitoring and surveillance. This approach holds promise as a screening tool for establishing baseline ARD levels that can be used to inform and prioritize decision making regarding management of ARD sources and human exposure routes. Citation: Port JA, Cullen AC, Wallace JC, Smith MN, Faustman EM. 2014. Metagenomic frameworks for monitoring antibiotic resistance in aquatic environments. Environ Health Perspect 122:222–228; http://dx.doi.org/10.1289/ehp.1307009 PMID:24334622

Metagenomic frameworks for monitoring antibiotic resistance in aquatic environments.

PubMed

Port, Jesse A; Cullen, Alison C; Wallace, James C; Smith, Marissa N; Faustman, Elaine M

2014-03-01

High-throughput genomic technologies offer new approaches for environmental health monitoring, including metagenomic surveillance of antibiotic resistance determinants (ARDs). Although natural environments serve as reservoirs for antibiotic resistance genes that can be transferred to pathogenic and human commensal bacteria, monitoring of these determinants has been infrequent and incomplete. Furthermore, surveillance efforts have not been integrated into public health decision making. We used a metagenomic epidemiology-based approach to develop an ARD index that quantifies antibiotic resistance potential, and we analyzed this index for common modal patterns across environmental samples. We also explored how metagenomic data such as this index could be conceptually framed within an early risk management context. We analyzed 25 published data sets from shotgun pyrosequencing projects. The samples consisted of microbial community DNA collected from marine and freshwater environments across a gradient of human impact. We used principal component analysis to identify index patterns across samples. We observed significant differences in the overall index and index subcategory levels when comparing ecosystems more proximal versus distal to human impact. The selection of different sequence similarity thresholds strongly influenced the index measurements. Unique index subcategory modes distinguished the different metagenomes. Broad-scale screening of ARD potential using this index revealed utility for framing environmental health monitoring and surveillance. This approach holds promise as a screening tool for establishing baseline ARD levels that can be used to inform and prioritize decision making regarding management of ARD sources and human exposure routes. Port JA, Cullen AC, Wallace JC, Smith MN, Faustman EM. 2014. Metagenomic frameworks for monitoring antibiotic resistance in aquatic environments. Environ Health Perspect 122:222–228; http://dx.doi.org/10.1289/ehp.1307009

Shiga Toxin-Producing Escherichia coli Isolated from Bovine Mastitic Milk: Serogroups, Virulence Factors, and Antibiotic Resistance Properties

PubMed Central

Momtaz, Hassan; Safarpoor Dehkordi, Farhad; Taktaz, Taghi; Rezvani, Amir; Yarali, Sajad

2012-01-01

The aim of this study was to detect the virulence factors, serogroups, and antibiotic resistance properties of Shiga toxin-producing Escherichia coli, by using 268 bovine mastitic milk samples which were diagnosed using California Mastitis Test. After E. coli identification, PCR assays were developed for detection of different virulence genes, serogroups, and antibiotic resistance genes of Escherichia coli. The antibiotic resistance pattern was studied using disk diffusion method. Out of 268 samples, 73 (27.23%) were positive for Escherichia coli, and, out of 73 positive samples, 15 (20.54%) were O26 and 11 (15.06%) were O157 so they were the highest while O111 was not detected in any sample so it was the lowest serogroup. Out of 73 STEC strains, 11 (15.06%) and 36 (49.31%) were EHEC and AEEC, respectively. All of the EHEC strains had stx1, eaeA, and ehly, virulence genes, while in AEEC strains stx1 had the highest prevalence (77.77%), followed by eaeA (55.55%). Totally, aadA1 (65.95%) had the highest while blaSHV (6.38%) had the lowest prevalence of antibiotic resistance genes. The disk diffusion method showed that the STEC strains had the highest resistance to penicillin (100%), followed by tetracycline (57.44%), while resistance to cephalothin (6.38%) was the lowest. PMID:23213293

Antibiotic resistance profile and virulence genes of uropathogenic Escherichia coli isolates in relation to phylogeny.

PubMed

Adib, N; Ghanbarpour, R; Solatzadeh, H; Alizade, H

2014-03-01

Escherichia coli (E. coli) strains are the major cause of urinary tract infections (UTI) and belong to the large group of extra-intestinal pathogenic E. coli. The purposes of this study were to determine the antibiotic resistance profile, virulence genes and phylogenetic background of E. coli isolates from UTI cases. A total of 137 E. coli isolates were obtained from UTI samples. The antimicrobial susceptibility of confirmed isolates was determined by disk diffusion method against eight antibiotics. The isolates were examined to determine the presence and prevalence of selected virulence genes including iucD, sfa/focDE, papEF and hly. ECOR phylo-groups of isolates were determined by detection of yjaA and chuA genes and fragment TspE4.C2. The antibiogram results showed that 71% of the isolates were resistant to cefazolin, 60.42% to co-trimoxazole, 54.16% to nalidixic acid, 36.45% to gentamicin, 29.18% to ciprofloxacin, 14.58% to cefepime, 6.25% to nitrofurantoin and 0.00% to imipenem. Twenty-two antibiotic resistance patterns were observed among the isolates. Virulence genotyping of isolates revealed that 58.39% isolates had at least one of the four virulence genes. The iucD gene was the most prevalent gene (43.06%). The other genes including sfa/focDE, papEF and hly genes were detected in 35.76%, 18.97% and 2.18% isolates, respectively. Nine combination patterns of the virulence genes were detected in isolates. Phylotyping of 137 isolates revealed that the isolates fell into A (45.99%), B1 (13.14%), B2 (19.71%) and D (21.16%) groups. Phylotyping of multidrug resistant isolates indicated that these isolates are mostly in A (60.34%) and D (20.38%) groups. In conclusion, the isolates that possessed the iucD, sfa/focDE, papEF and hly virulence genes mostly belonged to A and B2 groups, whereas antibiotic resistant isolates were in groups A and D. Escherichia coli strains carrying virulence factors and antibiotic resistance are distributed in specific phylogenetic background.

Extremely High Prevalence of Metronidazole-Resistant Helicobacter pylori Strains in Mountain People (Karen and Hmong) in Thailand

PubMed Central

Vilaichone, Ratha-korn; Ratanachu-ek, Thawee; Gamnarai, Pornpen; Chaithongrat, Supakarn; Uchida, Tomahisa; Yamaoka, Yoshio; Mahachai, Varocha

2016-01-01

This study aimed to survey the prevalence, patterns of antibiotic resistance, and clinical factors associated with antibiotic resistance in Helicobacter pylori among the Karen and Hmong mountain people of Thailand. We recruited dyspeptic patients in the Maesod district, Tak Province, Thailand. All subjects underwent upper gastrointestinal endoscopy, and three antral gastric biopsies were obtained for rapid urease tests and culture. An epsilometer was used to determine the minimum inhibitory concentrations of amoxicillin (AMX), clarithromycin (CLR), metronidazole (MNZ), levofloxacin (LVX), ciprofloxacin (CIP), and tetracycline (TET). A total of 291 subjects were enrolled; 149 (51.2%) were infected with H. pylori. Helicobacter pylori infection was present in 47.1% of Thai, 51.7% of Karen, and 58.7% of Hmong subjects. Antibiotic resistance was present in 75.8% including AMX (0.8%), TET (0%), CLR (5.6%), MNZ (71.8%), CIP (19.4%), LVX (19.4%), and multidrug resistance in 21.8%. Karen subjects had the highest prevalence of MNZ resistance (84.6%), and Hmong subjects had the highest prevalence of fluoroquinolone (27.3%) and multidrug (34.1%) resistance. MNZ plus fluoroquinolone (14.5%) was the most common multidrug resistance. There was no association between clinical factors and antibiotic resistance. MNZ resistance was prevalent, whereas fluoroquinolone- and multidrug-resistant H. pylori infections are important problems in mountain people of Thailand. PMID:26880772

Multidrug and co-resistance patterns of non-fermenting Gram-negative bacilli involved in ventilator-associated pneumonia carrying class 1 integron in the North of Iran.

PubMed

Bagheri-Nesami, Masoumeh; Rezai, Mohammad Sadegh; Ahangarkani, Fatemeh; Rafiei, Alireza; Nikkhah, Attieh; Eslami, Gohar; Shafahi, Kheironesa; Hajalibeig, Azin; Khajavi, Rezvan

2017-09-01

Ventilator-associated pneumonia (VAP) due to non-fermenting Gram-negative bacilli (NFGNB), especially Pseudomonas aeruginosa and Acinetobacter spp., is one of the main hospital-acquired infections leading to mortality and morbidity, especially in intensive care units (ICUs). This study seeks to determine the multidrug and co-resistance (MDR) patterns of NFGNB that are agents of VAP, and assess the presence of class 1 integron in these bacteria. This cross-sectional study involved VAP patients admitted in the ICUs of 18 hospitals in the Mazandaran province, located in the North of Iran. The antibiotic susceptibility pattern was determined by the minimum inhibitory concentration (MIC) test by using broth microdilution method. Presence of class 1 integron was evaluated by the polymerase chain reaction (PCR) assay. Out of a total of 83 patients who were microbiologically diagnosed as VAP, 52 non-duplicated NFGNBs (24 P. aeruginosa and 28 A. baumannii ) were causative of VAP, out of which MDR NFGNBs were responsible for 48 (57.83%) cases. The frequencies of MDR NFGNBs were as follows: 27 (56.25%) A. baumannii and 21 (43.75%) P. aeruginosa . P. aeruginosa isolates were resistant to all aminoglycoside antibiotics (50%), ciprofloxacin (45.8%), ceftazidime (70.8%), cefepime (87.5%), colistin (62.5%), and imipenem (29.2%). A. baumannii isolates were resistant to aminoglycosides (53.6%), ciprofloxacin (85.7%), ceftazidime (92. 9%), cefepime (92.9%), colistin (35.7%), and imipenem (57.1%). Twelve isolates were resistant to all 10 tested antibiotics. The number of rates of class 1 integron, positive for MDR P. aeruginosa and MDR A. baumannii , were 20 (95.23%) and 21 (77.78%), respectively. The high prevalence of multidrug resistance and incidence of class 1 integron is a therapeutic concern. Employing antibiotic stewardship in hospitals could prevent the dissemination of MDR bacteria.

Antibiotic Resistance of Salmonella spp. Isolated from Shrimp Farming Freshwater Environment in Northeast Region of Brazil

PubMed Central

Carvalho, Fátima C. T.; Sousa, Oscarina V.; Carvalho, Edirsana M. R.; Hofer, Ernesto; Vieira, Regine H. S. F.

2013-01-01

This study investigated the presence and antibiotic resistance of Salmonella spp. in a shrimp farming environment in Northeast Region of Brazil. Samples of water and sediments from two farms rearing freshwater-acclimated Litopenaeus vannamei were examined for the presence of Salmonella. Afterwards, Salmonella isolates were serotyped, the antimicrobial resistance was determined by a disk diffusion method, and the plasmid curing was performed for resistant isolates. A total of 30 (16.12%) of the 186 isolates were confirmed to be Salmonella spp., belonging to five serovars: S. serovar Saintpaul, S. serovar Infantis, S. serovar Panama, S. serovar Madelia, and S. serovar Braenderup, along with 2 subspecies: S. enterica serovar houtenae and S. enterica serovar enterica. About twenty-three percent of the isolates were resistant to at least one antibiotic, and twenty percent were resistant to at least two antibiotics. Three strains isolated from water samples (pond and inlet canal) exhibited multiresistance to ampicillin, tetracycline, oxytetracycline, and nitrofurantoin. One of them had a plasmid with genes conferring resistance to nitrofurantoin and ampicillin. The incidence of bacteria pathogenic to humans in a shrimp farming environment, as well as their drug-resistance pattern revealed in this study, emphasizes the need for a more rigorous attention to this area. PMID:24455280

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

PubMed

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

2017-12-01

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

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

PubMed

Reyhanath, Pilakka Veettil; Kutty, Ranjeet

2014-04-01

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

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

PubMed

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

2017-11-01

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

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.

[Antibiotic susceptibility of Staphylococcus aureus and Streptococcus pneumoniae in healthy carrier individuals in primary care in Barcelona area].

PubMed

Llor, Carles; Boada, Albert; Pons-Vigués, Mariona; Grenzner, Elisabet; Juvé, Rosa; Almeda, Jesús

2018-01-01

The information available on antibiotic resistance patterns are generally based on specimens from hospitalised individuals. This study was aimed at evaluating the antibiotic resistance rate of nasal carriage strains of Staphylococcus aureus and Streptococcus pneumoniae in healthy individuals, in accordance with age and gender, attended in Primary Care Centres (PCC). Cross-sectional study. Seven PCC in the Barcelona area. Healthy nasal carriers aged 4years or more who did not present with any sign of infectious disease, and had not taken any antibiotic or had been hospitalised in the previous 3months. A total of 3,969 nasal swabs valid for identification were collected between 2010 and 2011 and were sent to one central microbiological laboratory for isolation of both pathogens. Resistance to common antibiotics was determined on the basis of the current European Committee on Antimicrobial Susceptibility Testing guidelines on cut-off points. The prevalence of methicillin-resistant S.aureus was 1.3% (95%CI: 0.5-2.1%), with resistance rates of 87.1% to phenoxymethylpenicillin and 11.6% to azithromycin, with no significant differences with age and gender. A total of 2.4% (95CI%: 0.1-4.7%) of the pneumococcal strains were highly resistant to both phenoxymethylpenicillin and macrolides, whereas the highest resistance rates were to cefaclor (53.3%), followed by tetracycline (20%) and cefuroxime (12.1%). These pathogens have lower resistance rates in the community than in the hospital setting. Primary Care physicians must be more aware of the current antimicrobial resistance, in order to ensure prudent use of antibiotics. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Pattern of Antibiotic Resistance Among Community Derived Isolates of Enterobacteriaceae Using Urine Sample: A Study From Northern India

PubMed Central

Lohiya, Ayush; Kapil, Arti; Gupta, Sanjeev Kumar; Misra, Puneet; Rai, Sanjay K.

2015-01-01

Background Despite world-wide evidence of increased antibiotic resistance, there is scarce data on antibiotic resistance in community settings. One of the reason being difficulty in collection of biological specimen (traditionally stool) in community from apparently healthy individuals. Hence, finding an alternative specimen that is easier to obtain in a community setting or in large scale surveys for the purpose, is crucial. We conducted this study to explore the feasibility of using urine samples for deriving community based estimates of antibiotic resistance and to estimate the magnitude of resistance among urinary isolates of Escherichia coli and Klebsiella pneumonia against multiple antibiotics in apparently healthy individuals residing in a rural community of Haryana, North India. Materials and Methods Eligible individuals were apparently healthy, aged 18 years or older. Using the health management information system (HMIS) of Ballabgarh Health Demographic Surveillance System (HDSS), sampling frame was prepared. Potential individuals were identified using simple random sampling. Random urine sample was collected in a sterile container and transported to laboratory under ambient condition. Species identification and antibiotic susceptibility testing for Enterobacteriaceae was done using Clinical Laboratory and Standards Institute (CLSI) 2012 guidelines. Multi-drug resistant (MDR) Enterobacteriaceae, Extended Spectrum Beta Lactamase (ESBL) producing Enterobacteriaceae, and Carbapenem producing Enterobacteriaceae (CRE) were identified from the urine samples. Results A total of 433 individuals participated in the study (non-response rate – 13.4%), out of which 58 (13.4%) were positive for Enterobacteriaceae, 8.1% for E. coli and 5.3% for K. pneumoniae. Resistance against penicillin (amoxicillin/ampicillin) for E. coli and K. pneumoniae was 62.8% and 100.0% respectively. Isolates resistant to co-trimoxazole were 5.7% and 0.0% respectively. None of the isolates were resistant to imipenem, and meropenem. Conclusion and recommendations It is feasible to use urine sample to study magnitude of antibiotic resistance in population based surveys. At community level, resistance to amoxicillin was considerable, negligible for co-trimoxazole, and to higher antibiotics including carbapenems. PMID:26393150

Antibiotic susceptibility patterns and resistance genes of starter cultures and probiotic bacteria used in food.

PubMed

Kastner, Sabine; Perreten, Vincent; Bleuler, Helen; Hugenschmidt, Gabriel; Lacroix, Christophe; Meile, Leo

2006-03-01

A survey of starter and probiotic cultures was carried out to determine the current antibiotic resistance situation in microbial food additives in Switzerland. Two hundred isolates from 90 different sources were typed by molecular and other methods to belong to the genera Lactobacillus (74 samples), Staphylococcus (33 samples), Bifidobacterium (6 samples), Pediococcus (5 samples), or were categorized as lactococci or streptococci (82 samples). They were screened for phenotypic resistances to 20 antibiotics by the disk diffusion method. Twenty-seven isolates exhibiting resistances that are not an intrinsic feature of the respective genera were further analyzed by microarray hybridization as a tool to trace back phenotypic resistances to specific genetic determinants. Their presence was finally verified by PCR amplification or Southern hybridization. These studies resulted in the detection of the tetracycline resistance gene tet(K) in 5 Staphylococcus isolates used as meat starter cultures, the tetracycline resistance gene tet(W) in the probiotic cultures Bifidobacterium lactis DSM 10140 and Lactobacillus reuteri SD 2112 (residing on a plasmid), and the lincosamide resistance gene lnu(A) (formerly linA) in L. reuteri SD 2112.

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.

Antibiotic resistant airborne bacteria and their multidrug resistance pattern at University teaching referral Hospital in South Ethiopia.

PubMed

Solomon, Fithamlak Bisetegen; Wadilo, Fiseha Wada; Arota, Amsalu Amache; Abraham, Yishak Leka

2017-04-12

Hospitals provide a reservoir of microorganisms, many of which are multi-resistant to antibiotics. Emergence of multi-drug resistant strains in a hospital environment, particularly in developing countries is an increasing problem to infection treatment. This study aims at assessing antibiotic resistant airborne bacterial isolates. A cross-sectional study was conducted at Wolaita Sodo university teaching and referral Hospital. Indoor air samples were collected by using passive air sampling method. Sample processing and antimicrobial susceptibility testing were done following standard bacteriological techniques. The data was analyzed using SPSS version 20. Medically important bacterial pathogens, Coagulase negative staphylococci (29.6%), Staphylococcus aureus (26.3%), Enterococci species, Enterococcus faecalis and Enterococcus faecium (16.5%), Acinetobacter species (9.5%), Escherichia coli (5.8%) and Pseudomonas aeruginosa (5.3%) were isolated. Antibiotic resistance rate ranging from 7.5 to 87.5% was detected for all isolates. Acinetobacter species showed a high rate of resistance for trimethoprim-sulfamethoxazole, gentamicin (78.2%) and ciprofloxacin (82.6%), 28 (38.9%) of S. aureus isolates were meticillin resistant, and 7.5% Enterococci isolates of were vancomycin resistant. 75.3% of all bacterial pathogen were multi-drug resistant. Among them, 74.6% were gram positive and 84% were gram negative. Multi-drug resistance were observed among 84.6% of P. aeruginosa, of 82.5% Enterococcii, E. coli 78.6%, S. aureus 76.6%, and Coagulase negative staphylococci of 73.6%. Indoor environment of the hospital was contaminated with airborne microbiotas, which are common cause of post-surgical site infection in the study area. Bacterial isolates were highly resistant to commonly used antibiotics with high multi-drug resistance percentage. So air quality of hospital environment, in restricted settings deserves attention, and requires long-term surveillance to protect both patients and healthcare workers.

Antibiotic Use and Antimicrobial Resistance of Surgical Patients with Peritonitis at a Tertiary Referral Hospital in Rwanda.

PubMed

Rickard, Jennifer; Ngarambe, Christian; Ndayizeye, Leonard; Smart, Blair; Riviello, Robert; Majyambere, Jean Paul; Ghebre, Rahel G

There is growing recognition of the worsening problem of antibiotic resistance and the need for antibiotic stewardship in low-resource settings. The aim of this study was to describe antibiotic use and antimicrobial resistance in patients undergoing surgery for peritonitis at a Rwandan referral hospital. All surgical patients with peritonitis at a Rwandan referral hospital were enrolled. Prospective data were collected on epidemiology, clinical features, interventions, and outcomes. Antibiotic agents were prescribed and cultures were collected according to surgeon discretion. High risk for antibiotic treatment failure or death was defined as patients with severe sepsis, older than 70 years of age, tumor, or operating room delay more than 24 hours from hospital admission. Logistic regression was used to determine factors associated with high risk of antibiotic treatment failure or death. Over a six-month period, 280 patients underwent operation for peritonitis; 79 patients were excluded because no infectious etiology was identified at operation. Data on antibiotic usage were available for 165 patients. The most common diagnoses were intestinal obstruction (n = 43) and appendicitis (n = 36). Most patients received antibiotic agents, the most of of which being third-generation cephalosporins (n = 149; 90%) and metronidazole (n = 140; 85%). The mean duration of antibiotics was 5.1 days (range: 0-14). Overall, 80 (54%) patients were high-risk for antibiotic treatment failure or death. Risk for antibiotic treatment failure or death was associated with localized peritonitis (p = 0.001) and high American Society of Anesthesiologist score (p = 0.003). Cultures were collected from 33 patients and seven patients had an organism isolated. Escherichia coli was identified in in five surgical specimens and two 2 urine cultures. All Escherichia coli specimens showed resistance to cephalosporins. Broad antibiotic coverage with third-generation cephalosporins and metronidazole is common in Rwandan surgical patients with peritonitis. Areas for improvement should focus on choice and duration of antibiotic agents, tailored to underlying diagnosis and risk factors for antibiotic treatment failure or death. More data are needed on antibiotic resistance patterns to guide antimicrobial therapy.

Investigating Undergraduate Students’ Use of Intuitive Reasoning and Evolutionary Knowledge in Explanations of Antibiotic Resistance

PubMed Central

Richard, Melissa; Coley, John D.; Tanner, Kimberly D.

2017-01-01

Natural selection is a central concept throughout biology; however, it is a process frequently misunderstood. Bacterial resistance to antibiotic medications provides a contextual example of the relevance of evolutionary theory and is also commonly misunderstood. While research has shed light on student misconceptions of natural selection, minimal study has focused on misconceptions of antibiotic resistance. Additionally, research has focused on the degree to which misconceptions may be based in the complexity of biological information or in pedagogical choices, rather than in deep-seated cognitive patterns. Cognitive psychology research has established that humans develop early intuitive assumptions to make sense of the world. In this study, we used a written assessment tool to investigate undergraduate students’ misconceptions of antibiotic resistance, use of intuitive reasoning, and application of evolutionary knowledge to antibiotic resistance. We found a majority of students produced and agreed with misconceptions, and intuitive reasoning was present in nearly all students’ written explanations. Acceptance of a misconception was significantly associated with production of a hypothesized form of intuitive thinking (all p ≤ 0.05). Intuitive reasoning may represent a subtle but innately appealing linguistic shorthand, and instructor awareness of intuitive reasoning’s relation to student misunderstandings has potential for addressing persistent misconceptions. PMID:28821540

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

PubMed

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

2016-11-01

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

Antimicrobial susceptibility pattern of Shigella spp. isolated from children under 5 years of age attending tertiary care hospitals, Nepal along with first finding of ESBL-production.

PubMed

Dhital, Subhash; Sherchand, Jeevan Bahadur; Pokharel, Bharat Mani; Parajuli, Keshab; Mishra, Shyam Kumar; Sharma, Sangita; Kattel, Hari Prasad; Khadka, Sundar; Khatiwada, Sulochana; Rijal, Basista

2017-06-05

Shigella is an important cause of bacterial gastroenteritis in resource-poor countries. The treatment of shigellosis mostly requires antibiotics. However, the increase of multidrug resistance along with emergence of extended-spectrum β-lactamase and ciprofloxacin resistance among Shigella spp. has challenged the situation. This study was conducted to determine the distribution of species and antibiotic susceptibility pattern of Shigella species isolated from stool specimen among children less than 5 years of age in Nepal. Out of total 717 stool samples collected, 15 cases of Shigella spp. was isolated which includes 12 S. flexneri and 3 S. sonnei. Multidrug resistance was found among 13(86%) of the isolates. One of the isolates of S. flexneri was found to be ESBL-producer with MIC >256 mg/L for cefixime. The high occurrence of multidrug resistance among Shigella spp. along with a case of ESBL-production for the first time in Nepal alarms the concerns about dissemination of the resistant isolates. So, systemic monitoring of the antimicrobial susceptibility pattern of Shigella spp. is becoming crucial to guide therapy.

Primary antibiotic resistance in Helicobacter pylori in the Asia-Pacific region: a systematic review and meta-analysis.

PubMed

Kuo, Yu-Ting; Liou, Jyh-Ming; El-Omar, Emad M; Wu, Jeng-Yih; Leow, Alex Hwong Ruey; Goh, Khean Lee; Das, Rajashree; Lu, Hong; Lin, Jaw-Town; Tu, Yu-Kang; Yamaoka, Yoshio; Wu, Ming-Shiang

2017-10-01

So far, a comprehensive systematic review and meta-analysis has not been done of the prevalence of primary antibiotic resistance in Helicobacter pylori in the Asia-Pacific region. We aimed to assess the trends and regional differences in primary antibiotic resistance to H pylori in the Asia-Pacific region and to examine the relation between resistance and first-line eradication. We did a systematic review and meta-analysis of primary antibiotic resistance to H pylori and the efficacy of first-line regimens in the Asia-Pacific region. We searched PubMed, Embase, and the Cochrane Library for articles published between Jan 1, 1990, and Sept 30, 2016; we also searched abstracts from international conferences. Both observational studies and randomised controlled trials were eligible for inclusion in the analysis of primary antibiotic resistance, but only randomised controlled trials were eligible for inclusion in the analysis of efficacy of first-line therapies. Meta-analysis was by the random-effects model to account for the substantial variations in resistance across the region. We did subgroup analyses by country and study period (ie, before 2000, 2001-05, 2006-10, and 2011-15) to establish country-specific prevalences of primary antibiotic resistance and first-line eradication rates. This study is registered with PROSPERO, number CRD42017057905. 176 articles from 24 countries were included in our analysis of antibiotic resistance. The overall mean prevalences of primary H pylori resistance were 17% (95% CI 15-18) for clarithromycin, 44% (95% CI 39-48) for metronidazole, 18% (95% CI 15-22) for levofloxacin, 3% (95% CI 2-5) for amoxicillin, and 4% (95% CI 2-5) for tetracycline. Prevalence of resistance to clarithromycin and levofloxacin rose significantly over time during the period investigated, whereas resistance to other antibiotics remained stable. 170 articles from 16 countries were included in analysis of efficacy of first-line therapies. We noted unsatisfactory efficacy (ie, <80%) with clarithromycin-containing regimens in countries where the clarithromycin resistance rates were higher than 20%. The prevalence of primary antibiotic resistance varied greatly among countries in the Asia-Pacific region, and thus treatment strategy should be adapted relative to country-specific resistance patterns. Clarithromycin-containing regimens should be avoided in countries where the prevalence of clarithromycin resistance is higher than 20%. Ministry of Health and Welfare of Taiwan, Ministry of Science and Technology of Taiwan, and Amity University. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

USDA-ARS?s Scientific Manuscript database

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

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

PubMed

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

2017-01-01

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

CARRIAGE OF MULTIDRUG RESISTANT ENTEROCOCCUS FAECIUM AND ENTEROCOCCUS FAECALIS AMONG APPARENTLY HEALTHY HUMANS.

PubMed

Adesida, Solayide A; Ezenta, Cynthia C; Adagbada, Ajoke O; Aladesokan, Amudat A; Coker, Akitoye O

2017-01-01

Enterococci are indigenous flora of the gastro-intestinal tracts of animals and humans. Recently, interest in two major species, E. faecium and E. faecalis , has heightened because of their ability to cause serious infections and their intrinsic resistance to antimicrobials. This study was aimed at determining the prevalence of E . faecium and E . faecalis in human faecal samples and evaluating the susceptibility of the isolates to antibiotics. One hundred faecal samples were collected from apparently healthy individuals and analysed using conventionalbacteriological methods. The susceptibility profile of the isolates to nine antibiotics were determined using disk diffusion method. Seventy-three (73) Enterococcus were phenotypically identified and 65 of the isolates were differentiated into 36 (55.4%) E. faecium and 29 (44.6%) E. faecalis . Eight (8) isolates could not be identified by the conventional biochemical methods employed. No dual colonization by the E. faecalis and E. faecium was observed and isolation rate was not dependent on sex of the participants. All the isolates were resistant to ceftriaxone, cefuroxime and ceftizoxime. Enterococcus faecium exhibited resistance toerythromycin (88.9%), gentamicin (77.8%), amoxicillin-clavulanate (63.9%), ofloxacin (44.4%), teicoplanin (19.4%) and vancomycin (16.7%). Enterococcus faecalis showed the least resistance to vancomycin (13.8%) and teicoplanin (27.7%). Remarkable multiple antibiotic resistances to the classes of antibiotic tested were observed among the two species. The high carriage rate of antibiotic resistant E. faecium and E. faecalis in this study provides information on the local antibiotic patterns of our enterococci isolates thereby suggesting that they could present as important reservoir and vehicle for dissemination of resistant genes in our community.

Impacts of reclaimed water irrigation on soil antibiotic resistome in urban parks of Victoria, Australia.

PubMed

Han, Xue-Mei; Hu, Hang-Wei; Shi, Xiu-Zhen; Wang, Jun-Tao; Han, Li-Li; Chen, Deli; He, Ji-Zheng

2016-04-01

The effluents from wastewater treatment plants have been recognized as a significant environmental reservoir of antibiotics and antibiotic resistance genes (ARGs). Reclaimed water irrigation (RWI) is increasingly used as a practical solution for combating water scarcity in arid and semiarid regions, however, impacts of RWI on the patterns of ARGs and the soil bacterial community remain unclear. Here, we used high-throughput quantitative PCR and terminal restriction fragment length polymorphism techniques to compare the diversity, abundance and composition of a broad-spectrum of ARGs and total bacteria in 12 urban parks with and without RWI in Victoria, Australia. A total of 40 unique ARGs were detected across all park soils, with genes conferring resistance to β-lactam being the most prevalent ARG type. The total numbers and the fold changes of the detected ARGs were significantly increased by RWI, and marked shifts in ARG patterns were also observed in urban parks with RWI compared to those without RWI. The changes in ARG patterns were paralleled by a significant effect of RWI on the bacterial community structure and a co-occurrence pattern of the detected ARG types. There were significant and positive correlations between the fold changes of the integrase intI1 gene and two β-lactam resistance genes (KPC and IMP-2 groups), but no significant impacts of RWI on the abundances of intI1 and the transposase tnpA gene were found, indicating that RWI did not improve the potential for horizontal gene transfer of soil ARGs. Taken together, our findings suggested that irrigation of urban parks with reclaimed water could influence the abundance, diversity, and compositions of a wide variety of soil ARGs of clinical relevance. Irrigation of urban parks with treated wastewater significantly increased the abundance and diversity of various antibiotic resistance genes, but did not significantly enhance their potential for horizontal gene transfer. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sulfonamide-Resistant Bacteria and Their Resistance Genes in Soils Fertilized with Manures from Jiangsu Province, Southeastern China

PubMed Central

Jiao, Shaojun; Zhang, Jun; Ye, Boping; Gao, Shixiang

2014-01-01

Antibiotic-resistant bacteria and genes are recognized as new environmental pollutants that warrant special concern. There were few reports on veterinary antibiotic-resistant bacteria and genes in China. This work systematically analyzed the prevalence and distribution of sulfonamide resistance genes in soils from the environments around poultry and livestock farms in Jiangsu Province, Southeastern China. The results showed that the animal manure application made the spread and abundance of antibiotic resistance genes (ARGs) increasingly in the soil. The frequency of sulfonamide resistance genes was sul1 > sul2 > sul3 in pig-manured soil DNA and sul2 > sul1 > sul3 in chicken-manured soil DNA. Further analysis suggested that the frequency distribution of the sul genes in the genomic DNA and plasmids of the SR isolates from manured soil was sul2 > sul1 > sul3 overall (p<0.05). The combination of sul1 and sul2 was the most frequent, and the co-existence of sul1 and sul3 was not found either in the genomic DNA or plasmids. The sample type, animal type and sampling time can influence the prevalence and distribution pattern of sulfonamide resistance genes. The present study also indicated that Bacillus, Pseudomonas and Shigella were the most prevalent sul-positive genera in the soil, suggesting a potential human health risk. The above results could be important in the evaluation of antibiotic-resistant bacteria and genes from manure as sources of agricultural soil pollution; the results also demonstrate the necessity and urgency of the regulation and supervision of veterinary antibiotics in China. PMID:25405870

Sulfonamide-resistant bacteria and their resistance genes in soils fertilized with manures from Jiangsu Province, Southeastern China.

PubMed

Wang, Na; Yang, Xiaohong; Jiao, Shaojun; Zhang, Jun; Ye, Boping; Gao, Shixiang

2014-01-01

Antibiotic-resistant bacteria and genes are recognized as new environmental pollutants that warrant special concern. There were few reports on veterinary antibiotic-resistant bacteria and genes in China. This work systematically analyzed the prevalence and distribution of sulfonamide resistance genes in soils from the environments around poultry and livestock farms in Jiangsu Province, Southeastern China. The results showed that the animal manure application made the spread and abundance of antibiotic resistance genes (ARGs) increasingly in the soil. The frequency of sulfonamide resistance genes was sul1 > sul2 > sul3 in pig-manured soil DNA and sul2 > sul1 > sul3 in chicken-manured soil DNA. Further analysis suggested that the frequency distribution of the sul genes in the genomic DNA and plasmids of the SR isolates from manured soil was sul2 > sul1 > sul3 overall (p<0.05). The combination of sul1 and sul2 was the most frequent, and the co-existence of sul1 and sul3 was not found either in the genomic DNA or plasmids. The sample type, animal type and sampling time can influence the prevalence and distribution pattern of sulfonamide resistance genes. The present study also indicated that Bacillus, Pseudomonas and Shigella were the most prevalent sul-positive genera in the soil, suggesting a potential human health risk. The above results could be important in the evaluation of antibiotic-resistant bacteria and genes from manure as sources of agricultural soil pollution; the results also demonstrate the necessity and urgency of the regulation and supervision of veterinary antibiotics in China.

Genomes of Salmonella with diverse patterns of antibiotic resistance (AR) revealed the dynamics of AR gene organization and detected resistance gene families found in Salmonella

USDA-ARS?s Scientific Manuscript database

We produced and assembled high quality draft genomes (~100X coverage) for 305 Salmonella from a diverse a group of over 100 serovars and diverse sources. Of these isolates, 119 were selected to capture a wide variety of different AR patterns. In our subsequent analyses we included 285 additional pub...

Antibiotic resistance patterns of urinary tract pathogens in Turkish children.

PubMed

Gunduz, Suzan; Uludağ Altun, Hatice

2018-01-01

Knowledge of local antimicrobial resistance patterns is essential for evidence- based empirical antibiotic prescribing. We aimed to investigate the distribution and changes in causative agents of urinary tract infections in children and the resistance rates, and to recommend the most appropriate antibiotics. In this retrospective study, we evaluated causative agents and antimicrobial resistance in urine isolates from the positive community from September 2014 to April 2016 in a single hospital in Ankara, Turkey. A total of 850 positive urine cultures were identified, of which 588 (69.2%) were from girls and 262 (30.8%) were from boys. Their mean age was 36.5 ± 45.0 months. The most common causative agent was Escherichia coli (64.2% of cases) followed by Klebsiella pneumoniae (14.9%). The overall resistance to ampicillin (62.6%), cephalothin (44.2%), co-trimoxazole (29.8%) and cefuroxime (28.7%) was significant. No resistance to imipenem was detected in the isolates. The least resistance was for amikacin, ceftriaxone, ciprofloxacin and cefepime (0.1, 2.4, 7.5 and 8.3%, respectively). Imipenem was the most active agent against E. coli followed by amikacin (0.2%), ceftriaxone (2.7%) and nitrofurantoin (5.1%). High resistance rates to nitrofurantoin were detected in K. pneumoniae, Proteus and Enterobacteriae . E. coli was the most common causative agent of urinary tract infection in children. Ampicillin, trimethoprim-sulfometaxazole, cephalothin and cefuroxim had the highest resistance rates against urinary tract pathogens in our center. For oral empirical antibiotherapy, cefixime is the most appropriate choice so as to include Klebsiella strains.

Antibiotic resistance: What is so special about multidrug-resistant Gram-negative bacteria?

PubMed Central

Exner, Martin; Bhattacharya, Sanjay; Christiansen, Bärbel; Gebel, Jürgen; Goroncy-Bermes, Peter; Hartemann, Philippe; Heeg, Peter; Ilschner, Carola; Kramer, Axel; Larson, Elaine; Merkens, Wolfgang; Mielke, Martin; Oltmanns, Peter; Ross, Birgit; Rotter, Manfred; Schmithausen, Ricarda Maria; Sonntag, Hans-Günther; Trautmann, Matthias

2017-01-01

In the past years infections caused by multidrug-resistant Gram-negative bacteria have dramatically increased in all parts of the world. This consensus paper is based on presentations, subsequent discussions and an appraisal of current literature by a panel of international experts invited by the Rudolf Schülke Stiftung, Hamburg. It deals with the epidemiology and the inherent properties of Gram-negative bacteria, elucidating the patterns of the spread of antibiotic resistance, highlighting reservoirs as well as transmission pathways and risk factors for infection, mortality, treatment and prevention options as well as the consequences of their prevalence in livestock. Following a global, One Health approach and based on the evaluation of the existing knowledge about these pathogens, this paper gives recommendations for prevention and infection control measures as well as proposals for various target groups to tackle the threats posed by Gram-negative bacteria and prevent the spread and emergence of new antibiotic resistances. PMID:28451516

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

PubMed

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

2013-01-01

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

New antibiotics for bad bugs: where are we?

PubMed Central

2013-01-01

Bacterial resistance to antibiotics is growing up day by day in both community and hospital setting, with a significant impact on the mortality and morbidity rates and the financial burden that is associated. In the last two decades multi drug resistant microorganisms (both hospital- and community-acquired) challenged the scientific groups into developing new antimicrobial compounds that can provide safety in use according to the new regulation, good efficacy patterns, and low resistance profile. In this review we made an evaluation of present data regarding the new classes and the new molecules from already existing classes of antibiotics and the ongoing trends in antimicrobial development. Infectious Diseases Society of America (IDSA) supported a proGram, called “the ′10 × ´20′ initiative”, to develop ten new systemic antibacterial drugs within 2020. The microorganisms mainly involved in the resistance process, so called the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and enterobacteriaceae) were the main targets. In the era of antimicrobial resistance the new antimicrobial agents like fifth generation cephalosporins, carbapenems, monobactams, β-lactamases inhibitors, aminoglycosides, quinolones, oxazolidones, glycopeptides, and tetracyclines active against Gram-positive pathogens, like vancomycin-resistant S. aureus (VRSA) and MRSA, penicillin-resistant streptococci, and vancomycin resistant Enterococcus (VRE) but also against highly resistant Gram-negative organisms are more than welcome. Of these compounds some are already approved by official agencies, some are still in study, but the need of new antibiotics still does not cover the increasing prevalence of antibiotic-resistant bacterial infections. Therefore the management of antimicrobial resistance should also include fostering coordinated actions by all stakeholders, creating policy guidance, support for surveillance and technical assistance. PMID:23984642

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

Antibiotic Rotation for Febrile Neutropenic Patients with Hematological Malignancies: Clinical Significance of Antibiotic Heterogeneity

PubMed Central

Chong, Yong; Shimoda, Shinji; Yakushiji, Hiroko; Ito, Yoshikiyo; Miyamoto, Toshihiro; Kamimura, Tomohiko; Shimono, Nobuyuki; Akashi, Koichi

2013-01-01

Background Our unit adopted the single administration of cefepime as the initial treatment for febrile episodes in neutropenic patients with hematological malignancies. However, recently, cefepime-resistant gram-negative bacteremia, including those with extended-spectrum β-lactamase (ESBL)-producers, was frequently observed in these patients. Therefore, we instituted a rotation of primary antibiotics for febrile neutropenic patients in an attempt to control antibiotic resistance. Methods This prospective trial was performed from August 2008 through March 2011 at our unit. After a pre-intervention period, in which cefepime was used as the initial agent for febrile neutropenia, 4 primary antibiotics, namely, piperacillin-tazobactam, ciprofloxacin, meropenem, and cefepime, were rotated at 1-month intervals over 20 months. Blood and surveillance cultures were conducted for febrile episodes, in order to assess the etiology, the resistance pattern (particularly to cefepime), and the prognosis. Results In this trial, 219 patients were registered. A 65.9% reduction in the use of cefepime occurred after the antibiotic rotation. In the surveillance stool cultures, the detection rate of cefepime-resistant gram-negative isolates, of which ESBL-producers were predominant, declined significantly after the intervention (8.5 vs 0.9 episodes per 1000 patient days before and after intervention respectively, P<0.01). Interestingly, ESBL-related bacteremia was not detected after the initiation of the trial (1.7 vs 0.0 episodes per 1000 patient days before and after intervention respectively, P<0.01). Infection-related mortality was comparable between the 2 periods. Conclusions We implemented a monthly rotation of primary antibiotics for febrile neutropenic patients. An antibiotic heterogeneity strategy, mainly performed as a cycling regimen, would be useful for controlling antimicrobial resistance among patients treated for febrile neutropenia. PMID:23372683

Antibiotic resistance in children with recurrent or complicated urinary tract infection.

PubMed

Younis, N; Quol, K; Al-Momani, T; Al-Awaisheh, F; Al-Kayed, D

2009-01-01

Urinary tract infection is certainly one of the most common childhood infections. Emerging resistance to the antibiotics is not unusual. Current hospitalization for children with urinary tract infection is reserved for severe or complicated cases. The aim of the present study was to determine the antibiotic resistance pattern among children with recurrent or complicated urinary tract infection. A retrospective study carried out at Prince Hashem hospital, Zarqa city, eastern Jordan and involved 336 episodes of culture proved urinary tract infection obtained from 121 patients with recurrent UTI, who used prophylactic antibiotics during the period from April 1, 2004 to December 31, 2006. The isolated microorganisms and there antibiotics susceptibility were studied. Seventy three patients (60.3%) were found to have some forms of urinary tract anomaly, significantly more prevalent among male children P<0.001. Vesicoureteral reflux being the most common (58.9%). Renal scars were significantly more prevalent among those with complicated rather than recurrent urinary tract infection (64.3% vs. 16.6%, P<0.001). Gram negative organisms were the most frequent isolates in patients with recurrent and complicated urinary tract infection. Proteus, Pseudomonas and Candida spp. were more prevalent in patients with complicated (P<0.001), and isolates in patients with UTA were significantly more resistant to most antibiotics tested. Pediatric urine culture isolates are becoming increasingly resistant to commonly used antibiotics. Empirical treatment with Trimethoprim-Sulfamethoxazole (TMP-SMX) or Cephalexin as the initial drug is ineffective. Nitrofurantoin and Nalidixic acid can be considered as the first line antibiotics for prophylaxis and or treatment of patients with recurrent UTI, while Meropenam and Ciprofloxacin can be used empirically in treating patients with complicated UTI.

Patterns of isolation of common gram positive bacterial pathogens and their susceptibilities to antimicrobial agents in Jimma Hospital.

PubMed

Gebreselassie, Solomon

2002-04-01

Gram positive bacteria are frequently emerging as antibiotic resistant pathogens, causing serious infections than ever before in the ill and debilitated patients. The pattern of isolation and the antimicrobial susceptibilities of common Gram positive cocci including Staphylococcus aureus, coagulase negative staphylococcus (CoNS), Streptococcus pyogenes, Enterococcus species and Streptococcus pneumoniae was investigated between January 1997 and June 2000 in Jimma Hospital. Of the 500 specimens collected from children and adults, 116 (23.2%) consisted of one or more of the above organisms. The following strains: Staphylococcus aureus, 47 (40.5%), CoNS, 36 (31.0%), Streptococcus pneumoniae, 26 (22.4%) Streptococcus pyogenes, 5 (4.3%) and Streptococcus faecalis, 2(1.7%) were isolated from different specimens including pus, sputum, urine, stool, blood and oro/nasopharyngeal swabs of patients. The in vitro activities of 14 different antibiotics including penicillin G, ampicillin, cloxacillin, cephalothin, gentamicin, kanamycin, tetracycline, chloramphenicol, erythromycin, trimethoprim-sulfamethoxazole, streptomycin, methicillin, vancomycin and clindamycin was determined against the clinical bacterial isolates. The antimicrobial activities were evaluated by agar diffusion technique using Mueller-Hinton agar according to NCCLS recommendations. The majority of the pathogens, 59(50.9%) were recovered from upper respiratory tract infections and 17 (14.6%) from the lower respiratory tract. The resistance patterns of S. aureus, CoNS, S. pneumoniae and enterococci to penicillin was 91.5%, 94.4%, 7.7% and 100% respectively. Penicillin, ampicillin and cloxacillin showed low effects (< 60%) on both S. aureus and CoNS. Multi-drug resistance was observed in all the gram-positive isolates, especially higher in staphylococcus species. All isolates of S. aureus (100%) were susceptible to vancomycin, clindamycin and gentamicin. In order to reduce morbidity and mortality due to antibiotic resistance susceptibility testing should be performed for the proper management of bacterial infections. This entails the need for national surveillance to monitor antibiotic resistance in bacteria by susceptibility testing using reliable methods.

Secretion expression of human neutrophil peptide 1 (HNP1) in Pichia pastoris and its functional analysis against antibiotic-resistant Helicobacter pylori.

PubMed

Zhang, Xiaolin; Jiang, Anmin; Qi, Banghua; Yu, Hao; Xiong, Youyi; Zhou, Guoliang; Qin, Meisong; Dou, Jinfeng; Wang, Jianfei

2018-06-01

Human neutrophil peptide 1 (HNP1) is a small (3.44 kDa) cationic peptide that is a distinct member of the defensin family. HNP1 plays a crucial role in controlling bacterial infections, particularly by antibiotic-resistant bacteria, through membrane perforation patterns. The structural characteristics of HNP1's three intramolecular disulfide bridges cause difficulty in its synthesis via chemical methods. In this study, bioactive recombinant HNP1 was produced using the Pichia pastoris (P. Pichia) expression system. HNP1 was fused with the polyhedrin of Bombyx mori and enhanced green fluorescent protein (EGFP) to prevent HNP1 toxicity in yeast host cells under direct expression. An enterokinase protease cleavage site (amino acid sequence DDDDK) was designed upstream of the HNP1 peptide to obtain the antibacterial peptide HNP1 with native structure after it was cleaved by the enterokinase. The fusion HNP1 protein (FHNP1) was successfully expressed and had a molecular mass of approximately 62.6 kDa, as determined using SDS-PAGE and Western blot. Then, the recovered FHNP1 was digested and purified; Tricine-SDS-PAGE results showed that HNP1 was successfully released from FHNP1. Functional analysis of induction against antibiotic-resistant Helicobacter pylori (H. pylori) showed that it was challenging for HNP1 to acquire resistance to the antibiotic-resistant H. pylori. Moreover, in vitro studies showed that HNP1 exerted a strong effect against antibiotic-resistant H. pylori activity. Furthermore, the animal model of H. pylori infection established in vivo showed that HNP1 significantly reduced the colonization of antibiotic-resistant H. pylori in the stomach. Our study indicated that this could be a new potential avenue for large-scale production of HNP1 for therapeutic application against the antibiotic-resistant H. pylori infection in humans.

Antibiotic resistance of native and faecal bacteria isolated from rivers, reservoirs and sewage treatment facilities in Victoria, south-eastern Australia.

PubMed

Boon, P I; Cattanach, M

1999-03-01

The incidence of resistance to ampicillin, chloramphenicol, kanamycin, nalidixic acid, neomycin and streptomycin was significantly greater (P < 0.001) in native heterotrophic bacteria than in Escherichia coli isolated from a range of sites along the Yarra River in south-eastern Australia. There was no significant difference in the incidence of resistance between native and faecal bacteria to tetracycline. Both groups were almost totally resistant to penicillin. Multivariate analyses indicated little clear spatial pattern in the incidence of resistance in native bacteria from upstream vs downstream sites along the Yarra River. In contrast, E. coli isolated from upstream (rural) sites tended to have a lower incidence of resistance than isolates from downstream (urban) sites. These findings have implications for the use of antibiotic resistance as a bacteriological water quality parameter.

Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa.

PubMed

Malema, Mokaba Shirley; Abia, Akebe Luther King; Tandlich, Roman; Zuma, Bonga; Mwenge Kahinda, Jean-Marc; Ubomba-Jaswa, Eunice

2018-05-01

Although many developing countries use harvested rainwater (HRW) for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert ® 18/Quanti-Tray ® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR), and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) ( ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli.

Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa

PubMed Central

Malema, Mokaba Shirley; Tandlich, Roman; Zuma, Bonga; Mwenge Kahinda, Jean-Marc

2018-01-01

Although many developing countries use harvested rainwater (HRW) for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert®18/Quanti-Tray® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR), and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) (ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli. PMID:29723970

MOLECULAR CHARACTERISATION AND ANTIMICROBIAL RESISTANCE PATTERNS OF ESCHERICHIA COLI ISOLATES FROM GOATS SLAUGHTERED IN PARTS OF KENYA.

PubMed

Njoroge, S; Muigai, A W T; Njiruh, P N; Kariuki, S

2013-03-01

To determine the antibiotic resistance patterns of pathogenic Escherichia coli on goat meat carcass at Huruma and Kiserian abattoirs in Kenya. Laboratory based study. Huruma and Kiserian abattoirs in Kenya, 400 slaughtered goats inspected by veterinary health officers and approved for human consumption. A Total of 400 slaughtered goats which were inspected by veterinary health officers and approved for human consumption were sampled from Huruma and Kiserian abattoir. Goat carcass swabs were collected by passing each swab tissue on four parts of the carcass mainly neck, right and left forelimbs, right and left hind limbs, and brisket. A total of 54 E. coli isolates were isolated and confirmed to be pathogenic. The percentage of isolates resistant to various microbial agents was recorded as follows: ampicillin (26 %), amoxycillin-clavulanic acid (17%), tetracycline (15%), chroramphenicol (4%), and ceftrixone (2% each). All Escherichia coli isolates were susceptible to gentamicin sulphamethaxazole-trimethomprin, kanamycin, cetriazididine (CAZ, 30pg), ciproxacin, nalidixic acid and chloramphenicol. Isolates were resistant to one or more of the antibiotics tested. Among the drugs tested, resistance was more frequently observed against ampicillin, amoxycillin-clavulanic acid, tetracycline, ceftrixone and chroramphenicol antibiotics. Among the isolates 26(48%) were positive for the stx1 gene, 19(35%) had the eae gene, 10(19%) possessed est gene,while 8(15%) harboured elt gene. Overall five isolates (10%) possessed aspu gene and two (4%) had aggR gene. No isolate possessed ipah gene. This study demonstrated that there is a significant level of antimicrobial resistance in pathogenic E. coli isolated from goat meat from Huruma and Kiserian abattoir. This indicates that goat meat from abattoirs could pose a risk of transmission of pathogenic antibiotic resistant strains to human. Poor hygienic standards and indiscriminate use of antimicrobials are the two main reasons for the presence of resistant pathogens in goat carcasses. Implemention of appropriate hygiene measures to control contamination of meat with pathogenic E. coli.

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.

The magnitude of antibiotic resistance to Helicobacter pylori in Africa and identified mutations which confer resistance to antibiotics: systematic review and meta-analysis.

PubMed

Jaka, Hyasinta; Rhee, Jee Ah; Östlundh, Linda; Smart, Luke; Peck, Robert; Mueller, Andreas; Kasang, Christa; Mshana, Stephen E

2018-04-24

Worldwide Helicobacter pylori (H.pylori) treatment is of great challenge due to increased antibiotic resistance. The burden of H. pylori antibiotic resistance in Africa is high with unclear information regarding the real magnitude. This systematic review and meta-analysis was conducted to investigate the magnitude of H.pylori antibiotic resistance in Africa to gain insight of the extent of the problem among H.pylori naïve treatment patients. The search was performed in the academic databases, Embase, PubMed, Web of Science and Africa Wide Information. ProQuest Dissertation and Theses, Scopus, Ethos, Africa Index Medicus (WHO), BioMed Central Proceedings, BASE, British Library, Open grey, Library of Congress and the New York Academy of Grey Literature Report were additionally searched for grey literature. Published articles from Africa on H.pylori antibiotic resistance between 1986 and June 2017 were systematically reviewed to estimate the H. pylori extent of resistance to macrolides, quinolones, amoxicillin, tetracycline and metronidazole. In 26 articles a total of 2085 isolates were tested for metronidazole, 1530 for amoxicillin, 1277 for tetracycline, 1752 for clarithromycin and 823 for quinolones.The overall pooled proportion of H.pylori resistance to quinolones, clarithromycin, tetracycline, metronidazole and amoxicillin were: (17.4%, 95%CI 12.8 - 21.9), (29.2%, 95%CI:26.7-31.8), (48.7%, 95%CI: 44.5-52.9), (75.8%, 95% CI: 74.1-.77.4) and (72.6%, 95% CI: 68.6-76.6), respectively. The commonest mutation detected were A2143G (49/97) for clarithromycin, RdxA (41/56) for metronidazole and D87I (16/40) for quinolones. Prevalence of metronidazole, clarithromycin, and amoxicillin resistance is high in developing world including Africa. This could impair the first line triple therapy of the H.pylori infection. There is a need of conducting surveillance of H.pylori susceptibility pattern in Africa for dual and triple resistance which can be used for the empirical treatment.

Emergence of KPC-producing Klebsiella pneumoniae in Uruguay: infection control and molecular characterization

PubMed Central

Marquez, C; Ingold, A; Echeverría, N; Acevedo, A; Vignoli, R; García-Fulgueiras, V; Viroga, J; Gonzalez, O; Odizzio, V; Etulain, K; Nuñez, E; Albornoz, H; Borthagaray, G; Galiana, A

2014-01-01

We describe the first outbreak of Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP), the infection control measures adopted and the shift in resistance patterns of isolates during antibiotic treatment. The ST258 KPC-KP strain exhibited a multiresistant antibiotic phenotype including co-resistance to gentamycin, colistin and tigecycline intermediate susceptibility. Isolates before and after treatment had different behaviour concerning their antibiotic susceptibility and the population analysis profile study. A progressive increase in the aminoglycosides (acquiring amicacin resistance) and β-lactam MICs, and a decreased susceptibility to fosfomycin was observed throughout the administration of combined antimicrobial regimens including meropenem. A high meropenem resistance KPC-KP homogeneous population (MIC 256 Jg/mL), could arise from the meropenem heterogeneous low-level resistance KPC-KP population (MIC 8 Jg/mL), by the selective pressure of the prolonged meropenem therapy. The kpc gene was inserted in a Tn4401 isoform a, and no transconjugants were detected. The core measures adopted were successful to prevent evolution towards resistance dissemination. PMID:25356345

Imipenem-resistance in Serratia marcescens is mediated by plasmid expression of KPC-2.

PubMed

Su, W-Q; Zhu, Y-Q; Deng, N-M; Li, L

2017-04-01

Imipenem is a broad-spectrum carbapenem antibiotic with applications against severe bacterial infections. Here, we describe the identification of imipenem-resistant Serratia marcescens in our hospital and the role of plasmid-mediated KPC-2 expression in imipenem resistance. We used the modified Hodge test to detect carbapenemase produced in imipenem-resistant strains. His resistance can be transferred to E. coli in co-culture tests, which implicates the plasmid in imipenem resistance. PCR amplification from the plasmid identified two products consistent with KPC-2 of 583 and 1050 bp that were also present in E. coli after co-culture. The restriction pattern for both plasmids was identical, supporting the transfer from the S. marcescens isolate to E. coli. Finally, gene sequencing confirmed KPC-2 in the plasmid. Due to the presence of KPC-2 in the imipenem-resistant S. marcescens, we propose that KPC-2 mediates antibiotic resistance in the S. marcescens isolate.

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

PubMed

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

2017-03-20

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

Local resistance patterns to antimicrobials in internal medicine: a focused report from the REGIMEN (REGistro Infezioni in MEdicina INterna) study.

PubMed

Cei, Marco; Pardelli, Riccardo; Sani, Spartaco; Mumoli, Nicola

2014-02-01

The treatment for infections in hospitalized patients can be summarized in the timely start of empirical therapy, followed by adjustment on the basis of isolates and microbial susceptibilities. Initial therapy may be based on international guidelines. However, to know local frequencies of bacterial and fungal strains together with patterns of drug resistance should be a better approach to therapy. REGIMEN is a retrospective observational study of all consecutive recorded bacterial and fungal isolates, collected between October 2009 and August 2011 from patients admitted in a 53-bedded ward of internal medicine of a non-teaching Italian hospital. We investigated type of samples and of microorganisms, patterns of susceptibility and resistance to antibiotics, and in-hospital mortality. A total of 504 samples were examined (244 from urine, 189 from blood and 71 from skin and various exudates). Participants were old (mean age, 83 years), and so overall mortality was high (20 %). There were high frequencies of drug resistance; only 27.9 % of urinary gram-negatives and 52.6 % of blood gram-negatives were susceptible to levofloxacin. Susceptibility profiles compatible with the presence of extended-spectrum beta-lactamases were present in 64.2 % of gram-negative strains, and 10.1 % were also resistant to carbapenems. ESKAPE organisms account for a third of all bacterial infections. Local patterns of drug resistance should influence empirical antibiotic therapy for patients admitted in internal medicine wards, where mortality is high.

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.

High prevalence of diverse vancomycin resistance Enterococcus faecium isolates in clinical and environmental sources in ICU wards in southwest of Iran.

PubMed

Arshadi, Maniya; Douraghi, Masoumeh; Shokoohizadeh, Leili; Moosavian, Seyed Mojtaba; Pourmand, Mohammad Reza

2017-10-01

This study aimed at determining the prevalence, antibiotic resistance patterns, and genetic linkage of Vancomycin Resistant Enterococcus faecium (VREfm) from different sources in the southwest of Iran. A total of 51 VREfm isolates were obtained and subjected to antibiotic susceptibility testing, carriage of virulence genes, and pulsed-field gel electrophoresis (PFGE) method. All the VRE isolates exhibited a high level of resistance to teicoplanin, ampicillin, erythromycin, ciprofloxacin, and gentamicin, also carried the vanA gene. A total of 59% and 34% of the VREfm strains harbored esp and hyl genes, respectively. The results from PFGE showed 31 PFGE patterns including 10 common types (CT) and 21 single types (ST) among the VRE isolates. Furthermore, isolates from different sources in each common type revealed cross transmission between clinical and environmental sources. Overall, the study showed a high prevalence of diverse VRE faecium strains with threatening resistance phenotypes in the environment and clinical sections among different ICU wards of Ahvaz hospitals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antibiotics and Antibiotic Resistance

MedlinePlus

... Medicine Safely Antibiotics and Antibiotic Resistance Antibiotics and Antibiotic Resistance Share Tweet Linkedin Pin it More sharing options ... throughout the world are becoming resistant to antibiotics. Antibiotic resistance has been called one of the world's most ...

Etiology and antimicrobial resistance patterns in pediatric urinary tract infection.

PubMed

Wang, Jun; He, Lijiao; Sha, Jintong; Zhu, Haobo; Huang, Liqu; Zhu, Xiaojiang; Dong, Jun; Li, Guogen; Ge, Zheng; Lu, Rugang; Ma, Geng; Shi, Yaqi; Guo, Yunfei

2018-02-02

Urinary tract infection (UTI) is one of most common pediatric infections. The aim of this study was to investigate the etiology and antimicrobial resistance patterns in children hospitalized at Children's Hospital of Nanjing Medical University. We conducted a retrospective, descriptive study of all UTI from 1 January 2013 to 30 November 2016 in children discharged from Nanjing Children's Hospital. The isolated pathogens and their resistance patterns were examined using midstream urine culture. A total of 2,316 children with UTI were included in the study. The occurrence rates of isolated pathogens were as follows: Enterococcus spp., 35.15%; Escherichia coli, 22.32%; Staphylococcus aureus spp., 7.73%; Streptococcus spp., 7.51%; and Klebsiella spp., 6.95%. Uropathogens had a low susceptibility to linezolid (3.47%), vancomycin (0.92%), imipenem (5.74%), and amikacin (3.17%), but they had a high susceptibility to erythromycin (90.52%), penicillin G (74.01%), cefotaxime (71.41%), cefazolin (73.41%), cefuroxime (72.52%), and aztreonam (70.11%). There is high antibiotic resistance in hospitalized children with UTI. Susceptibility testing should be carried out on all clinical isolates, and the empirical antibiotic treatment should be altered accordingly. © 2018 Japan Pediatric Society.

Increasing Antimicrobial Resistance Monitored in Surveillance Analysis of Blood Stream Infections in Febrile Neutropenic Pediatric Oncology Patients.

PubMed

El-Mahallawy, Hadir A; Hassan, Safaa Shawky; El-Wakil, Mohamed; Moneer, Manar M; Shalaby, Lobna

2015-01-01

Continuous surveillance of pattern of blood stream infection is necessary in febrile neutropenia (FN)especially with the recent escalating trend in the management of pediatric cancer patients towards intensified regimens and with the increase in infections caused by resistant organisms limiting the choice of antibiotics. To monitor change in pattern of blood stream infections (BSI) in FN pediatric cancer patients. Surveillance of FN episodes with positive BSI was prospectively monitored and compared to a previous surveillance in the same pediatric oncology unit. A total of 232 BSI positive episodes were documented in 192 patients during a 6 months period. The results of recent surveillance analysis showed an increase in intensified regimens of chemotherapy, antimicrobial resistance, fungal infections, and prolonged duration of episodes when compared to previous surveillance, with p value sof <0.001, 0.005, 0.021, and <0.001, respectively. There was an apparent decrease in the crude mortality but this was not statistically significant, to 6% in 2011 from 10 % in 2006. The pattern of BSI at our institution is still inclining towards gram positive organisms but is showing a shift towards more antibiotic resistance and fungal infections.

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

PubMed

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

2017-12-01

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

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

PubMed

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

2016-01-01

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

Antibiotic resistance pattern and plasmid profiling of thermotolerant Escherichia coli isolates in drinking water.

PubMed

Subba, P; Joshi, D R; Bhatta, D R

2013-01-01

Antibiotic resistant Escherichia coli is potential source of transmission of resistance to other water borne pathogens where plasmid borne resistance is most significant. Drinking water samples were collected from different water sources: that is to say- tap, well and spring from different places of Kathmandu where E. coli and thermotolerant E. coli were isolated using membrane filtration technique. Antibiotic susceptibility was determined using a modified Kirby Bauer disc diffusion method and thermotolerant E. coli isolates from tap water were subjected for plasmid profiling. Type of water sources were not associated with the presence of coliform (P=0.155) and thermotolerant coliform (P=0.235) but the significant association was observed in thermotolerant coliform and thermotolerant E. coli for all sources tap (P=0.029), well (P=0.028), spring (P=0.05) but total coliform and E. coli association was found for well (P=0.01). All E. coli and thermotolerant E. coli isolates were susceptible to Ofloxacin, Chloramphenicol and Cotrimixazole. Resistance to Cefexime, Amikacin, Nalidixic acid, Amoxicillin, Tetracycline were 17 (54.8%), 9 (29%), 11 (35.5%), 25 (80.6%), 29 (93.5%) and 19 (57.6%), 12 (36.4%), 13 (39.4%), 31 (94%), 33 (100%) was observed in E. coli and thermotolerant E. coli respectively where 25 (75.8%) thermotolerant E. coli and 22 (70.9%) E. coli were observed with multiple drug resistance patterns. Single band of plasmid were observed in three MDRs and one non-MDR isolates and size varied from 2kb to >10kb. All Nalidixic acid resistant thermotolerant E. coli were found to harbor a plasmid. Presence of plasmid in Nalidixic acid resistant thermotolerant E. coli heightens public health issue and the need of monitoring Quinolone resistance bacteria in environment.

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.

Study of virulence factors of uropathogenic Escherichia coli and its antibiotic susceptibility pattern.

PubMed

Mittal, Seema; Sharma, Madhu; Chaudhary, Uma

2014-01-01

Urinary tract infection (UTI) is one of the most common nosocomial infections, caused by Escherichia coli. This study determined the presence of virulence factors in the organism and correlates it with the multi-drug resistance (MDR). The aim of the following study is to assess the virulence factors of uropathogenic E. coli and antibiotic susceptibility pattern. This was a prospective study conducted in the Department of Microbiology in PT. B. D. Sharma, PGIMS, Rohtak. The study was conducted over a period of 1 year. Urine samples received were processed as per standard microbiological procedures. Virulence factors such as hemolysin, hemagglutination, cell surface hydrophobicity, serum resistance, gelatinase and siderophore production were studied. The antimicrobial susceptibility was done as per Clinical and Laboratory Standard Institute Guidelines. The data was analyzed by using SPSS(Statistical Package for the social sciences) IBM Corporation version 17.0. A two sided P ≤ 0.05 was considered to be significant. Hemolysin production was seen in 47.4%, hemagglutination in 74.8%, cell surface hydrophobicity in 61%, serum resistance in 59%, gelatinase in 67.5% and siderophore production in 88% isolates. Nitrofurantoin was found to be most effective followed by, gatifloxacin and gentamicin. Twenty nine percent (29.62%) isolates were MDR. Therefore, the knowledge of virulence factors of E. coli and their antibiotic susceptibility pattern will help in better understanding of the organism and in the treatment of UTI.

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.

Characterization of Antibiotic Resistance Profiles of Ocular Enterobacteriaceae Isolates

PubMed Central

Paul-Satyaseela, Maneesh; Murali, Sowmiya; Thirunavukkarasu, Bharani; Naraharirao, Madhavan Hajib; Jambulingam, Malathi

2016-01-01

Emergence of extended-spectrum β-lactamase (ESBL) and fluoroquinolone resistance among ocular Enterobacteriaceae is increasing in higher frequency. Therefore, studies are being carried out to understand their multidrug resistance pattern. A total of 101 Enterobacteriaceae isolates recovered from various ocular diseases in a tertiary eye care center at Chennai, India during the period of January 2011 to June 2014 were studied. Forty one randomly chosen isolates were subjected to antibiotic susceptibility by minimum inhibitory concentration (MIC) and genotypic analysis. Of them, 16 were ESBL producers, one was carbapenemase producer and four were resistant to ertapenem which could be due to porin loss associated with AmpC production, and 17 were resistant to fluoroquinolones. Sixteen isolates harbored ESBL genes in which 14 had more than one gene and none of them were positive for blaNDM-1 gene. QNR genes were detected in 18 isolates. ESBL producers were predominantly isolated from conjunctiva. A high degree of ESBL production and fluoroquinolone resistance is seen among the genus Klebsiella sp. Hence, monitoring the rate of ESBL prevalence plays a vital role in the administration of appropriate intravitreal antibiotics to save the vision and also to reduce the development of drug resistance in ocular pathogens. PMID:27141313

Determinants of Quinolone versus Trimethoprim-Sulfamethoxazole Use for Outpatient Urinary Tract Infection

PubMed Central

Stuck, Anna K.; Täuber, Martin G.; Schabel, Maria; Lehmann, Thomas; Suter, Herbert

2012-01-01

Quinolones are increasingly favored over trimethoprim-sulfamethoxazole (TMP-SMX) for empirical treatment of uncomplicated urinary tract infection (UTI). This is associated with increasing resistance toward this broad-spectrum group of antibiotics. Our objective is to describe the prescribing patterns and identify determinants of the choice between TMP-SMX and quinolones for outpatient UTI treatment in Switzerland. An ongoing national Sentinel surveillance system was used to study 11,799 antibiotic prescriptions for UTI in adult outpatients and associated physician and patient factors between 2006 and 2008, to compare the prescription of quinolones versus that of TMP-SMX for treatment of UTI. Most UTI episodes were diagnosed as cystitis (90%). TMP-SMX was prescribed for one-fifth (22%) of UTIs. Independent predictors for prescribing quinolones were pyelonephritis and physicians with low thresholds for prescribing antibiotics for upper respiratory tract infections (“high prescribers”), whereas female patients were more likely to receive TMP-SMX. High-prescribing physicians also more often cared for patients who themselves favor antibiotic treatment (P < 0.001). Quinolones are commonly prescribed to outpatients with UTI. Nonclinical factors influence the choice of quinolones versus TMP-SMX, which may provide opportunities for interventions to improve prescribing patterns and control quinolone resistance. PMID:22232276

Cultivation and qPCR Detection of Pathogenic and Antibiotic-Resistant Bacterial Establishment in Naive Broiler Houses.

PubMed

Brooks, J P; McLaughlin, M R; Adeli, A; Miles, D M

2016-05-01

Conventional commercial broiler production involves the rearing of more than 20,000 broilers in a single confined space for approximately 6.5 wk. This environment is known for harboring pathogens and antibiotic-resistant bacteria, but studies have focused on previously established houses with mature litter microbial populations. In the current study, a set of three naive houses were followed from inception through 11 broiler flocks and monitored for ambient climatic conditions, bacterial pathogens, and antibiotic resistance. Within the first 3 wk of the first flock cycle, 100% of litter samples were positive for and , whereas was cultivation negative but PCR positive. Antibiotic resistance genes were ubiquitously distributed throughout the litter within the first flock, approaching 10 to 10 genomic units g. Preflock litter levels were approximately 10 CFU g for heterotrophic plate count bacteria, whereas midflock levels were >10 colony forming units (CFU) g; other indicators demonstrated similar increases. The influence of intrahouse sample location was minor. In all likelihood, given that preflock levels were negative for pathogens and antibiotic resistance genes and 4 to 5 Log lower than flock levels for indicators, incoming birds most likely provided the colonizing microbiome, although other sources were not ruled out. Most bacterial groups experienced a cyclical pattern of litter contamination seen in other studies, whereas microbial stabilization required approximately four flocks. This study represents a first-of-its-kind view into the time required for bacterial pathogens and antibiotic resistance to colonize and establish in naive broiler houses. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Odontogenic bacteria in periodontal disease and resistance patterns to common antibiotics used as treatment and prophylaxis in odontology in Spain.

PubMed

Maestre, J R; Bascones, A; Sánchez, P; Matesanz, P; Aguilar, Lorenzo; Giménez, M J; Pérez-Balcabao, I; Granizo, J J; Prieto, J

2007-03-01

Resistance in streptococci or Gram-negative bacteria is associated with antibiotic consumption. Scarce information exists on the antibiotic susceptibility of bacterial isolates from patients with periodontitis in countries with high antibiotic consumption, as this is an area in which microbiological testing is not performed in daily practice. The present study was undertaken to explore the susceptibility of bacterial isolates in periodontitis to antibiotics prescribed in odontology in Spain as treatment for local infections or prophylaxis for distant focal infections. Periodontal samples were prospectively collected in 48 patients classified by pocket depth of <4 mm and >or=4 mm. Species were identified by culture, selecting the five most frequent morphotypes per sample, and polymerase chain reaction (PCR). Susceptibility was determined by E-test. A total of 261 isolates were identified: 72.9% patients had Streptococcus oralis; 70.8% Streptococcus mitis; 60.4% Prevotella buccae; 39.6% Prevotella denticola; 37.5% Fusobacterium nucleatum; 35.4% Prevotella intermedia; 25% Capnocytophaga spp.; 23% Veillonella spp.; 22.9% Prevotella melaninogenica and Streptococcus sanguis; and <20% other species. Streptococcus viridans resistance rates were 0% for amoxicillin, approximately 10% for clindamycin, 9-22% for tetracycline, and for azithromycin ranged from 18.2% for S. sanguis to 47.7% for S. mitis. Prevotella isolates were susceptible to amoxicillin-clavulanic acid, with amoxicillin resistance ranging from 17.1% in P. buccae to 26.3% in P. denticola. Metronidazole resistance was <6% in all Prevotella species, while clindamycin resistance ranged from 0 to 21.1%. beta-Lactamase production was positive in 54.1% Prevotella spp., 38.9% F. nucleatum, 30% Capnocytophaga spp., and 10% Veillonella spp. In this study, amoxicillin-clavulanic acid was the most active antibiotic against all species tested, followed by metronidazole in the case of anaerobes.

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

PubMed

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

2012-06-01

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

Human Activity Determines the Presence of Integron-Associated and Antibiotic Resistance Genes in Southwestern British Columbia.

PubMed

Uyaguari-Díaz, Miguel I; Croxen, Matthew A; Luo, Zhiyao; Cronin, Kirby I; Chan, Michael; Baticados, Waren N; Nesbitt, Matthew J; Li, Shaorong; Miller, Kristina M; Dooley, Damion; Hsiao, William; Isaac-Renton, Judith L; Tang, Patrick; Prystajecky, Natalie

2018-01-01

The dissemination of antibiotic resistant bacteria from anthropogenic sources into the environment poses an emerging public health threat. Antibiotic resistance genes (ARGs) and gene-capturing systems such as integron-associated integrase genes ( intI ) play a key role in alterations of microbial communities and the spread of antibiotic resistant bacteria into the environment. In order to assess the effect of anthropogenic activities on watersheds in southwestern British Columbia, the presence of putative antibiotic resistance and integrase genes was analyzed in the microbiome of agricultural, urban influenced, and protected watersheds. A metagenomics approach and high-throughput quantitative PCR (HT qPCR) were used to screen for elements of resistance including ARGs and intI . Metagenomic sequencing of bacterial genomic DNA was used to characterize the resistome of microbial communities present in watersheds over a 1-year period. There was a low prevalence of ARGs relative to the microbial population (<1%). Analysis of the metagenomic sequences detected a total of 60 elements of resistance including 46 ARGs, intI1 , and groEL/ intI1 genes and 12 quaternary ammonium compounds ( qac ) resistance genes across all watershed locations. The relative abundance and richness of ARGs was found to be highest in agriculture impacted watersheds compared to urban and protected watersheds. A downstream transport pattern was observed in the impacted watersheds (urban and agricultural) during dry months. Similar to other reports, this study found a strong association between intI1 and ARGs (e.g., sul1 ), an association which may be used as a proxy for anthropogenic activities. Chemical analysis of water samples for three major groups of antibiotics was below the detection limit. However, the high richness and gene copy numbers (GCNs) of ARGs in impacted sites suggest that the effects of effluents on microbial communities are occurring even at low concentrations of antimicrobials in the water column. Antibiotic resistance and integrase genes in a year-long metagenomic study showed that ARGs were driven mainly by environmental factors from anthropogenized sites in agriculture and urban watersheds. Environmental factors such as land-use and water quality parameters accounted for 45% of the variability observed in watershed locations.

Human Activity Determines the Presence of Integron-Associated and Antibiotic Resistance Genes in Southwestern British Columbia

PubMed Central

Uyaguari-Díaz, Miguel I.; Croxen, Matthew A.; Luo, Zhiyao; Cronin, Kirby I.; Chan, Michael; Baticados, Waren N.; Nesbitt, Matthew J.; Li, Shaorong; Miller, Kristina M.; Dooley, Damion; Hsiao, William; Isaac-Renton, Judith L.; Tang, Patrick; Prystajecky, Natalie

2018-01-01

The dissemination of antibiotic resistant bacteria from anthropogenic sources into the environment poses an emerging public health threat. Antibiotic resistance genes (ARGs) and gene-capturing systems such as integron-associated integrase genes (intI) play a key role in alterations of microbial communities and the spread of antibiotic resistant bacteria into the environment. In order to assess the effect of anthropogenic activities on watersheds in southwestern British Columbia, the presence of putative antibiotic resistance and integrase genes was analyzed in the microbiome of agricultural, urban influenced, and protected watersheds. A metagenomics approach and high-throughput quantitative PCR (HT qPCR) were used to screen for elements of resistance including ARGs and intI. Metagenomic sequencing of bacterial genomic DNA was used to characterize the resistome of microbial communities present in watersheds over a 1-year period. There was a low prevalence of ARGs relative to the microbial population (<1%). Analysis of the metagenomic sequences detected a total of 60 elements of resistance including 46 ARGs, intI1, and groEL/intI1 genes and 12 quaternary ammonium compounds (qac) resistance genes across all watershed locations. The relative abundance and richness of ARGs was found to be highest in agriculture impacted watersheds compared to urban and protected watersheds. A downstream transport pattern was observed in the impacted watersheds (urban and agricultural) during dry months. Similar to other reports, this study found a strong association between intI1 and ARGs (e.g., sul1), an association which may be used as a proxy for anthropogenic activities. Chemical analysis of water samples for three major groups of antibiotics was below the detection limit. However, the high richness and gene copy numbers (GCNs) of ARGs in impacted sites suggest that the effects of effluents on microbial communities are occurring even at low concentrations of antimicrobials in the water column. Antibiotic resistance and integrase genes in a year-long metagenomic study showed that ARGs were driven mainly by environmental factors from anthropogenized sites in agriculture and urban watersheds. Environmental factors such as land-use and water quality parameters accounted for 45% of the variability observed in watershed locations. PMID:29765365

Serogroups, atypical biochemical characters, colicinogeny and antibiotic resistance pattern of Shiga toxin-producing Escherichia coli isolated from diarrhoeic calves in Gujarat, India.

PubMed

Arya, G; Roy, A; Choudhary, V; Yadav, M M; Joshi, C G

2008-01-01

This study was designed to investigate the antibiotic resistance, colicinogeny, serotyping and atypical biochemical characteristics of 41 Shiga toxin-producing Escherichia coli (STEC) strains detected using polymerase chain reaction from 90 E. coli strains isolated from 46 diarrhoeic calves. The STEC strains belonged to 14 different serogroups. Seventeen per cent of the STEC strains carried the eaeA gene while 14.28% of the 49 non-STEC strains were eaeA positive. Twenty eight (68.29%) of the 41 STEC strains were rhamnose non-fermentors. All the STEC strains revealed resistance to at least three of the antibiotics tested. 100% resistance was found against kanamycin and cephalexin followed by cephaloridine, enrofloxacin, amikacin, ampicillin, tetracycline, ceftiofur, ciprofloxacin, colistin and co-trimoxazole. Eighteen (44%) of the STEC strains produced colicin and all these colicinogenic strains were resistant to three or more antibiotics. Eleven STEC strains (26.82%) showed urease activity. The results of this study suggest that diarrhoeic calves are an important reservoir of STEC strains that are potentially pathogenic for farm animals and humans. Moreover, rhamnose fermentation, colicinogeny and atypical biochemical behaviour, such as urease activity, may serve as important markers or diagnostic tools for epidemiological surveys to trace the source of infection in disease outbreaks.

The determinants of the antibiotic resistance process.

PubMed

Franco, Beatriz Espinosa; Altagracia Martínez, Marina; Sánchez Rodríguez, Martha A; Wertheimer, Albert I

2009-01-01

The use of antibiotic drugs triggers a complex interaction involving many biological, sociological, and psychological determinants. Resistance to antibiotics is a serious worldwide problem which is increasing and has implications for morbidity, mortality, and health care both in hospitals and in the community. To analyze current research on the determinants of antibiotic resistance and comprehensively review the main factors in the process of resistance in order to aid our understanding and assessment of this problem. We conducted a MedLine search using the key words "determinants", "antibiotic", and "antibiotic resistance" to identify publications between 1995 and 2007 on the determinants of antibiotic resistance. Publications that did not address the determinants of antibiotic resistance were excluded. The process and determinants of antibiotic resistance are described, beginning with the development of antibiotics, resistance and the mechanisms of resistance, sociocultural determinants of resistance, the consequences of antibiotic resistance, and alternative measures proposed to combat antibiotic resistance. Analysis of the published literature identified the main determinants of antibiotic resistance as irrational use of antibiotics in humans and animal species, insufficient patient education when antibiotics are prescribed, lack of guidelines for treatment and control of infections, lack of scientific information for physicians on the rational use of antibiotics, and lack of official government policy on the rational use of antibiotics in public and private hospitals.

Choosing the correct empirical antibiotic for urinary tract infection in pediatric: Surveillance of antimicrobial susceptibility pattern of Escherichia coli by E-Test method.

PubMed

Sedighi, Iraj; Solgi, Abbas; Amanati, Ali; Alikhani, Mohammad Yousef

2014-12-01

Urinary Tract Infections (UTIs) are of the most common bacterial diseases worldwide. We investigate the antibiotic susceptibility patterns of Escherichia coli (E. coli) strains isolated from pediatric patients with community acquired urinary tract infection (UTI) to find a clinical guidance for choosing a right empirical antibiotic in these patients. In this cross sectional study, 100 urine specimens which were positive for E. coli had been investigated for antibiotics susceptibility pattern. The susceptibility to Co-trimoxazol (25μg), Amikacin (30μg), Ceftriaxone (30μg), Nalidixic Acid (30μg), Cefixime (5μg), and Nitrofurantoin (300μg) tested with Disk diffusion agar and MIC determined with the E-test. Mean age of patients was 38 Months. Girls had greater proportion than boys (74 versus 26%). In Disk diffusion method, 26% of the isolates were susceptible to cotrimoxazole. Susceptibility to amikacin, ceftriaxone, nitrofurantoin, nalidixic acid and cefixime was 94%, 66%, 97%, 62% and 52%, respectively. By E-Test method and according to CLSI criteria susceptibility for co-trimoxazol, amikacin, ceftriaxone and nalidixic acid was 37%, 97%, 67% and 50%, respectively. The highest percentage of agreement between Disk diffusion and E-Test method was found for amikacin (96%) and the lowest percentage for co-trimoxazole (89%). Treatment failure, prolonged or repeated hospitalization, increased costs of care, and increased mortality are some consequence of bacterial resistance in UTIs. Misuse of antibiotics in each geographic location directly affects antibiotic resistance pattern. In the treatment of UTI, proper selection of antimicrobial agents should be relevant to the bacterial susceptibility testing surveillance. According to our results, amikacin as an injectable drug and nitrofurantoin as an oral agent could be used as a drug of choice in our region for children with UTIs.

Surveillance of antibiotic resistance in Neisseria gonorrhoeae in the WHO Western Pacific and South East Asian Regions, 2009.

PubMed

2011-03-01

Long-term surveillance of antimicrobial resistance in Neisseria gonorrhoeae has been conducted in the World Health Organization (WHO) Western Pacific Region (WPR) to optimise antibiotic treatment of gonococcal disease since 1992. From 2007, the Gonococcal Antimicrobial Surveillance Programme (GASP) has been enhanced by the inclusion of data from the South East Asian Region (SEAR) and recruitment of additional centres in the WPR. Approximately 8,704 isolates of N. gonorrhoeae were examined for their susceptibility to one or more antibiotics used for the treatment of gonorrhoea, incorporating External Quality Assurance controlled methods, from reporting centres in 21 countries and/or jurisdictions. A high proportion of penicillin and/or quinolone resistance was again detected amongst isolates tested in North Asia and the WHO SEAR. In contrast, from the Pacific Island states Fiji reported low penicillin and quinolone resistance, New Caledonia again reported no penicillin resistance and little quinolone resistance, Tonga reported no penicillin resistance and there was a continued absence of quinolone resistance reported in Papua New Guinea in 2009. The proportion of gonococci reported as 'decreased susceptibility' and 'resistant' to the third-generation cephalosporin antibiotic ceftriaxone varied widely but no major changes were evident in cephalosporin minimum inhibitory concentrations (MIC) patterns in 2009. Altered cephalosporin susceptibility has been associated with treatment failures following therapy with oral third-generation cephalosporins. There is a need for revision and clarification of some of the in vitro criteria that are currently used to categorise the clinical importance of gonococci with different ceftriaxone and oral cephalosporin MIC levels. The number of instances of spectinomycin resistance remained low. A high proportion of strains tested continued to exhibit high-level plasmid mediated resistance to tetracyclines. The continuing emergence and spread of antibiotic resistant gonococci in and from the WHO WPR and SEAR suggests that surveillance programs such as GASP be maintained and expanded.

Antibiotic susceptibility profile of Haemophilus influenzae and transfer of co-trimoxazole resistance determinants.

PubMed

Mohd-Zain, Z; Kamsani, N H; Ismail, I S; Ahmad, N

2012-09-01

Prior to the implementation of Haemophilus influenzae type b vaccination worldwide, H. influenzae has been one of the main causative agents of community acquired pneumonia and meningitis in children. Due to the lack of information on the characteristics of the H. influenzae isolates that have previously been collected in Malaysia, the H. influenzae were assessed of their microbial susceptibility to commonly used antibiotics. Emphasis was made on strains that were resistance to co-trimoxazole (SXT) and their mode of transfer of the antibiotic resistance determinants were examined. A collection of 34 H. influenzae isolates was serotyped and antimicrobial susceptibility tests were performed to 11 antibiotics. To the isolates that were found to be resistant to co-trimoxazole, minimum inhibition concentration (MIC) to SXT was performed using Etest while agar dilution method was used to measure the individual MICs of trimethoprim (TMP) and sulfamethoxazole (SUL). These isolates were also examined for presence of plasmid by PCR and isolation method. Conjugal transfers of SXT-resistant genes to SXT-susceptible hosts were performed to determine their rate of transfer. Result showed that 20.6% of the total number of isolates was serotype B while the remaining was non-typeable. Antimicrobial susceptibility profile of all the isolates revealed that 58.8% was resistant to at least one antibiotic. Majority of these isolates were equally resistant to ampicillin and tetracycline (29.4% each), followed by resistance to SXT (26.5%). From nine isolates that were found to be SXT-resistant, five contained plasmid/s. Conjugal transfer experiment showed that these five isolates with plasmid transferred SXT-resistance determinants at a higher frequency than those without. From these observations, it is postulated that plasmid is not involved in the transfer of SXT-resistance genes but presence of plasmid facilitates their transfer. The information obtained from this study provides some basic knowledge on the antimicrobial susceptibility pattern of the H. influenzae isolates and their mode of transfer of SXT-resistance genes.

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

PubMed

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

2017-02-10

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

Deciphering the distance to antibiotic resistance for the pneumococcus using genome sequencing data

PubMed Central

Mobegi, Fredrick M.; Cremers, Amelieke J. H.; de Jonge, Marien I.; Bentley, Stephen D.; van Hijum, Sacha A. F. T.; Zomer, Aldert

2017-01-01

Advances in genome sequencing technologies and genome-wide association studies (GWAS) have provided unprecedented insights into the molecular basis of microbial phenotypes and enabled the identification of the underlying genetic variants in real populations. However, utilization of genome sequencing in clinical phenotyping of bacteria is challenging due to the lack of reliable and accurate approaches. Here, we report a method for predicting microbial resistance patterns using genome sequencing data. We analyzed whole genome sequences of 1,680 Streptococcus pneumoniae isolates from four independent populations using GWAS and identified probable hotspots of genetic variation which correlate with phenotypes of resistance to essential classes of antibiotics. With the premise that accumulation of putative resistance-conferring SNPs, potentially in combination with specific resistance genes, precedes full resistance, we retrogressively surveyed the hotspot loci and quantified the number of SNPs and/or genes, which if accumulated would confer full resistance to an otherwise susceptible strain. We name this approach the ‘distance to resistance’. It can be used to identify the creep towards complete antibiotics resistance in bacteria using genome sequencing. This approach serves as a basis for the development of future sequencing-based methods for predicting resistance profiles of bacterial strains in hospital microbiology and public health settings. PMID:28205635

Effect of Periodontal Therapy With Amoxicillin-Metronidazole on Pharyngeal Carriage of Penicillin- and Erythromycin-Resistant Viridans Streptococci.

PubMed

Mombelli, Andrea; Cionca, Norbert; Almaghlouth, Adnan; Cherkaoui, Abdessalam; Schrenzel, Jacques; Giannopoulou, Catherine

2016-05-01

Previous studies have focused on antibiotic resistance of Gram-negative bacteria before and after periodontal therapy. The purpose of this analysis is to assess changes in resistance patterns of the commensal Gram-positive microbiota. The viridans group streptococci (VGS) have been suggested to serve as reservoirs of resistance genes for more pathogenic streptococci and may be implicated in some non-oral infections. In this randomized clinical trial, 80 patients with periodontitis are distributed randomly into two groups. In group A, patients received 375 mg amoxicillin and 500 mg metronidazole three times per day for 7 days during the non-surgical treatment phase (T1). In group B, the antibiotics were administered during the surgical phase (T2). Resistance of VGS to penicillin and erythromycin was determined by the epsilometer test. At baseline, VGS from 12.5% (group A) and 11.8% (group B) of patients had a minimum inhibitory concentration (MIC) >2 μg/mL to penicillin. Three months after T1, VGS from 15.6% and 16.7% of patients had an MIC >2 μg/mL, respectively. Six months after T2 VGS from 5.9% and 5.9% and 12 months after T2 VGS from 6.1% and 6.3% patients had an MIC >2 μg/mL. There was no effect of therapy with antibiotics, administered either in T1 or T2, on the carriage of penicillin-resistant VGS. Erythromycin resistance was high at baseline and remained unchanged throughout the study. MICs for penicillin and erythromycin were correlated (P <0.05). Amoxicillin plus metronidazole did not significantly affect the resistance pattern of the VGS to penicillin or erythromycin.

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

PubMed

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

2013-01-01

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

Antibiotic resistance patterns in fecal bacteria isolated from Christmas shearwater (Puffinus nativitatis) and masked booby (Sula dactylatra) at remote Easter Island.

PubMed

Ardiles-Villegas, Karen; González-Acuña, Daniel; Waldenström, Jonas; Olsen, Björn; Hernández, Jorge

2011-09-01

Antibiotic use and its implications have been discussed extensively in the past decades. This situation has global consequences when antibiotic resistance becomes widespread in the intestinal bacterial flora of stationary and migratory birds. This study investigated the incidence of fecal bacteria and general antibiotic resistance, with special focus on extended spectrum beta-lactamase (ESBL) isolates, in two species of seabirds at remote Easter Island. We identified 11 species of bacteria from masked booby (Sula dactylatra) and Christmas shearwater (Puffinus nativitatis); five species of gram-negative bacilli, four species of Streptococcus (Enterococcus), and 2 species of Staphylococcus. In addition, 6 types of bacteria were determined barely to the genus level. General antibiotic susceptibility was measured in the 30 isolated Enterobacteriaceae to 11 antibiotics used in human and veterinary medicine. The 10 isolates that showed a phenotypic ESBL profile were verified by clavulanic acid inhibition in double mixture discs with cefpodoxime, and two ESBL strains were found, one strain in masked booby and one strain in Christmas shearwater. The two bacteria harboring the ESBL type were identified as Serratia odorifera biotype 1, which has zoonotic importance. Despite minimal human presence in the masked booby and Christmas shearwater habitats, and the extreme geographic isolation of Easter Island, we found several multiresistant bacteria and even two isolates with ESBL phenotypes. The finding of ESBLs has animal and public health significance and is of potential concern, especially because the investigation was limited in size and indicated that antibiotic-resistant bacteria now are distributed globally.

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

PubMed Central

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

2018-01-01

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

Resistance of Strains Producing Extended-Spectrum β-Lactamases Among Salmonella from Duck Carcasses at Slaughterhouses in Three Major Provinces of South Korea.

PubMed

Lee, Soo Kyoung; Choi, Dasom; Chon, Jung Whan; Seo, Kun Ho

2016-03-01

The current study was carried out to estimate Salmonella spp. contamination of duck carcasses and to determine the antibiotic susceptibility profiles and serotype distribution of the isolates. Salmonella spp. was detected in 21.7% (26/120) of fresh raw duck carcasses sampled at different slaughterhouses in South Korea. Eight Salmonella serovars were identified; the most prevalent serovar was S. Typhimurium (34.6%), followed by S. Virchow (30.8%). All isolates were resistant to at least one antibiotic, and five remarkable isolates were resistant to more than 10 antibiotics, including third- and fourth-generation cephalosporins. Additional phenotypic and genetic characterization demonstrated that these isolates harbored resistance genes to broad-spectrum β-lactams, blaCTX-M-15 and blaCMY-2 genes, among the most prevalent β-lactamase enzymes worldwide. Based on molecular subtyping performed using the DiversiLab™ automated repetitive-sequence-based PCR system, isolates were classified into cluster A and cluster B. Among β-lactamase-producing Salmonellas, the isolate showing >98% similarity in their repetitive-sequence-based PCR banding pattern seemed to have acquired the resistance gene (blaCMY-2) and thus a distinct multiresistance profile. Given that antibiotic-resistant genes might be transferred by plasmid-mediated conjugation, periodic microbiological assessment within slaughterhouses is recommended for pathogens not to be transmitted through cross-contamination during slaughtering and dressing.

Antimicrobial resistant coliform bacteria in the Gomti river water and determination of their tolerance level.

PubMed

Akhter, Asma; Imran, Mohd; Akhter, Firoz

2014-01-01

The distribution of resistance to ampicillin, chloramphenicol, sulfonamides, tetracycline, and streptomycin among coliform in the Gomti river water samples was investigated. The coliform populations were isolated on Mac Conky and eosin methylene blue (EMB) agar plates supplemented with antibiotics. The incidence of resistance among the coliform population varied considerably in different drug and water sampling sites. Coliform bacteria showed lower drug resistant viable count in sampling site-III (receiving treated wastewater) as compared to more polluted site-I and site-II. Viable count of coliform population obtained on both medium was recorded higher against erythromycin from sampling site-III. Lower viable count of coliforms was recorded against tetracycline in site-II and III. Similar resistance pattern was obtained in the frequency of E. coli and Enterobacter species from all the three sampling sites. Percentage of antibiotic resistant E. coli was observed higher than Enterobacter spp among the total coliforms against all antibiotics tested without Erythromycin and penicillin in site-I and II respectively. Isolates of E. coli and Enterobacter spp. showed their tolerance level (MIC) in the range of 2-100 against the antibiotics tested. Maximum number of isolates of both genus exhibited their MICs at lower concentration range 2-5µg/ml against ciprofloxacin, tetracyclin and amoxycillin. EMB - Eosin methylene blue, IMViC tests - Indole, Methyl Red, Voges Proskauer and Citrate Utilization Tests, MIC - Minimum inhibitory concentration.

Antimicrobial resistant coliform bacteria in the Gomti river water and determination of their tolerance level

PubMed Central

Akhter, Asma; Imran, Mohd; Akhter, Firoz

2014-01-01

The distribution of resistance to ampicillin, chloramphenicol, sulfonamides, tetracycline, and streptomycin among coliform in the Gomti river water samples was investigated. The coliform populations were isolated on Mac Conky and eosin methylene blue (EMB) agar plates supplemented with antibiotics. The incidence of resistance among the coliform population varied considerably in different drug and water sampling sites. Coliform bacteria showed lower drug resistant viable count in sampling site-III (receiving treated wastewater) as compared to more polluted site-I and site-II. Viable count of coliform population obtained on both medium was recorded higher against erythromycin from sampling site-III. Lower viable count of coliforms was recorded against tetracycline in site-II and III. Similar resistance pattern was obtained in the frequency of E. coli and Enterobacter species from all the three sampling sites. Percentage of antibiotic resistant E. coli was observed higher than Enterobacter spp among the total coliforms against all antibiotics tested without Erythromycin and penicillin in site-I and II respectively. Isolates of E. coli and Enterobacter spp. showed their tolerance level (MIC) in the range of 2-100 against the antibiotics tested. Maximum number of isolates of both genus exhibited their MICs at lower concentration range 2-5µg/ml against ciprofloxacin, tetracyclin and amoxycillin. Abbreviations EMB - Eosin methylene blue, IMViC tests - Indole, Methyl Red, Voges Proskauer and Citrate Utilization Tests, MIC - Minimum inhibitory concentration. PMID:24966515

Using a simple point-prevalence survey to define appropriate antibiotic prescribing in hospitalised children across the UK

PubMed Central

Gharbi, Myriam; Doerholt, Katja; Vergnano, Stefania; Bielicki, Julia Anna; Paulus, Stéphane; Menson, Esse; Riordan, Andrew; Lyall, Hermione; Patel, Sanjay Valabh; Bernatoniene, Jolanta; Versporten, Ann; Heginbothom, Maggie; Goossens, Herman; Sharland, Mike

2016-01-01

Background The National Health Service England, Commissioning for Quality and Innovation for Antimicrobial Resistance (CQUIN AMR) aims to reduce the total antibiotic consumption and the use of certain broad-spectrum antibiotics in secondary care. However, robust baseline antibiotic use data are lacking for hospitalised children. In this study, we aim to describe, compare and explain the prescription patterns of antibiotics within and between paediatric units in the UK and to provide a baseline for antibiotic prescribing for future improvement using CQUIN AMR guidance. Methods We conducted a cross-sectional study using a point prevalence survey (PPS) in 61 paediatric units across the UK. The standardised study protocol from the Antibiotic Resistance and Prescribing in European Children (ARPEC) project was used. All inpatients under 18 years of age present in the participating hospital on the day of the study were included except neonates. Results A total of 1247 (40.9%) of 3047 children hospitalised on the day of the PPS were on antibiotics. The proportion of children receiving antibiotics showed a wide variation between both district general and tertiary hospitals, with 36.4% ( 95% CI 33.4% to 39.4%) and 43.0% (95% CI 40.9% to 45.1%) of children prescribed antibiotics, respectively. About a quarter of children on antibiotic therapy received either a medical or surgical prophylaxis with parenteral administration being the main prescribed route for antibiotics (>60% of the prescriptions for both types of hospitals). General paediatrics units were surprisingly high prescribers of critical broad-spectrum antibiotics, that is, carbapenems and piperacillin-tazobactam. Conclusions We provide a robust baseline for antibiotic prescribing in hospitalised children in relation to current national stewardship efforts in the UK. Repeated PPS with further linkage to resistance data needs to be part of the antibiotic stewardship strategy to tackle the issue of suboptimal antibiotic use in hospitalised children. PMID:27810974

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

PubMed

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

2015-04-19

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

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.

Occurrence and antimicrobial susceptibility of Salmonella isolates recovered from the pig slaughter process in Romania.

PubMed

Morar, Adriana; Sala, Claudia; Imre, Kálmán

2015-01-15

Reported human salmonellosis cases have increased in Romania. Antibiotic susceptibility testing of Salmonella strains isolated from pork and chicken meat indicate a worrying multidrug resistance pattern. This study aimed to investigate the occurrence of Salmonella and to evaluate the antibiotic resistance of Salmonella strains in a pig slaughterhouse-processing complex, which receives animals from 30% of the large industrialized swine farms in Romania. A total of 108 samples, including pork (n = 47), packaged pork products (n = 44), scald water sludge (n = 8), and detritus from the hair removal machine of the slaughterhouse (n = 9) were examined for the presence of Salmonella through standard methods. The antibiotic susceptibility of the isolated strains to 17 antibiotics was tested using the Vitek 2 system. Twenty-six (24.1%) samples were found to be Salmonella positive; this included 25.5% of meat samples and 15.9% of packaged products, as well as samples from two different points of the slaughter (41.2%). Resistance was observed against tetracycline (61.5%), ampicillin (50%), piperacillin (50%), trimethoprim-sulfamethoxazole (34.6%), amoxicillin/clavulanic acid (26.9%), nitrofurantion (23.1%), cefazolin (15.4%), piperacillin/tazobactam (7.7%), imipenem (3.8%), ciprofloxacin (3.8%), and norfloxacin (3.8%). No resistance towards cefoxitin, cefotaxime, ceftazidime, cefepime, amikacin, and gentamicin was found. Our study demonstrated the occurrence of multidrug-resistant Salmonella strains in the investigated pork production complex and highlighted it as a potential source of human infections. The results demonstrate the seriousness of antibiotic resistance of Salmonella in Romania, while providing a useful insight for the treatment of human salmonellosis by specialists.

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

PubMed

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

2014-01-01

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

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

PubMed

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

2000-05-01

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

[Epidemic condition and molecular subtyping of ciprofloxacin and cefotaxime co-resistant Salmonella Indiana isolated from retail chicken carcasses in six provinces, China].

PubMed

Hu, Yujie; He, Yingying; Wang, Yeru; Cui, Shenghui; Chen, Qiuxia; Liu, Guihua; Chen, Qian; Zhou, Gang; Yang, Baowei; Huang, Jinlin; Yu, Hongxia; Li, Fengqin

2015-08-01

To elucidate the epidemic condition and molecular subtyping of ciprofloxacin and cefotaxime co-resistant Salmonella Indiana (S. Indiana) isolated from retail chicken carcasses in six provinces of China. A total of 2 647 Salmonella strains isolated from retail chicken carcasses collected from six provinces of China were subjected to antimicrobial susceptibility testing. All Salmonella isolates co-resistant to ciprofloxacin and cefotaxime were further characterized by serotyping, extended-spectrum beta-lactamases (ESBLs) producing strains screening and pulsed field gel electrophoresis (PFGE) typing. Among 2 629 Salmonella isolates tested, 227 (8.52%) isolates were co-resistant to ciprofloxacin and ceftazidime/cefotaxime (Beijing: 11.67% (99/874), Jilin: 8.20% (60/726), Guangdong: 1.39% (7/502), Jiangsu: 15.61% (42/260), Shaanxi: 8.56% (16/186), Inner Mongolia: 0 (0/81)), and 224 of them were identified as S. Indiana. 213 (95.10%) isolates of S. Indiana were ESBLs producing strains. All ciprofloxacin and cefotaxime co-resistant S. Indiana isolates developed a multi-drug resistant profile and 17.86% (40/224) of them were resistant to all antibiotics tested except carbapenems, and 50.89% (114/224) of them resistant to 9 antibiotics, additionally, 25.45% (57/224) of them showed multi-drug resistance to 8 antibiotics. All ciprofloxacin and cefotaxime co-resistant S. Indiana isolates were divided into 32 PFGE clusters and 150 PFGE patterns. Strains of S. Indiana from same or different sampling site and time seemed to either share the same PFGE patterns or be differential to each other in different regions. The results indicated that chicken carcasses collected from parts of China were heavily contaminated by ciprofloxacin and cefotaxime co-resistant S. Indiana and could serve as an important reservoir of ciprofloxacin and cefotaxime co-resistant Salmonella. Molecular subtyping results indicated that cross contamination or common pollution source might be in these strains.

Antimicrobial resistance and serotype prevalence of Salmonella isolated from dairy cattle in the southwestern United States.

PubMed

Edrington, T S; Schultz, C L; Bischoff, K M; Callaway, T R; Looper, M L; Genovese, K J; Jung, Y S; McReynolds, J L; Anderson, R C; Nisbet, D J

2004-01-01

Mature dairy cattle were sampled over a 2-year period (2001-2002) on six farms in New Mexico and Texas. Fecal samples (n = 1560) were collected via rectal palpation and cultured for Salmonella, and one isolate from each positive sample was serotyped. Three isolates of each serotype, with the exception of Salmonella Newport (n = 12), were examined for susceptibility to 17 antimicrobial agents. Twenty-two different serotypes were identified from a total of 393 Salmonella isolates. Montevideo was the predominant serotype (27%) followed by Mbandaka (15%), Senftenberg (11.4%), Newport (6.4%), Anatum (4.8%), and Give (4.8%). Salmonella Typhimurium and Dublin, two frequently reported serotypes, accounted for only 1% of the observed serotypes in this study. Sixty-four percent of the serotypes were susceptible to all 17 antimicrobials, 14% were resistant to a single agent, and 22% were multiresistant (2-11 types of resistance). All isolates tested were susceptible to amikacin, apramycin, imipenem, ceftriaxone, nalidixic acid, and ciprofloxacin. The most frequent types of resistance were to sulfamethoxazole, tetracycline, streptomycin, kanamycin, chloramphenicol, and ampicillin (ranging from 8.9 to 22.4%). Serotypes demonstrating multiple resistance included Dublin and Give (resistant to three or more antibiotics), Typhimurium (resistant to five antibiotics), and Newport (four and two isolates resistant to six and nine antibiotics, respectively). Class 1 integrons were present in only two Salmonella Dublin isolates and one Salmonella Newport isolate. The most prevalent resistance patterns observed in this study were toward antimicrobial agents commonly used in cattle, while all Salmonella isolates were susceptible to ceftriaxone and ciprofloxacin, antibiotics used in human medicine.

Molecular typing, antibiotic resistance, virulence gene and biofilm formation of different Salmonella enterica serotypes.

PubMed

Turki, Yousra; Mehr, Ines; Ouzari, Hadda; Khessairi, Amel; Hassen, Abdennaceur

2014-01-01

Salmonella enterica isolates representing commonly isolated serotypes in Tunisia were analyzed using genotyping and phenotyping methods. ERIC and ITS-PCR applied to 48 Salmonella spp. isolates revealed the presence of 12 and 10 different profiles, respectively. The distribution of profiles among serotypes demonstrated the presence of strains showing an identical fingerprinting pattern. All Salmonella strains used in this study were positive for the sdiA gene. Three Salmonella isolates belonging to serotypes Anatum, Enteritidis and Amsterdam were negative for the invA gene. The spvC gene was detected in thirteen isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Gallinarum and Montevideo. Antibiotic resistance was frequent among the recovered Salmonella isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Zanzibar and Derby. The majority of these isolates exhibited resistance to at least two antibiotic families. Four multidrug-resistant isolates were recovered from food animals and poultry products. These isolates exhibited not only resistance to tetracycline, sulphonamides, and ampicillin, but also have shown resistance to fluoroquinolones. Common resistance to nalidixic acid, ciprofloxacin and ofloxacin in two S. Anatum and S. Zanzibar strains isolated from raw meat and poultry was also obtained. Furthermore, wastewater and human isolates exhibited frequent resistance to nalidixic acid and tetracycline. Of all isolates, 33.5% were able to form biofilm.

[Antibiotic therapy of hospital-acquired pneumonia and its pharmacoeconomics].

PubMed

Kolář, Milan; Htoutou Sedláková, Miroslava; Urbánek, Karel; Uvízl, Radomír; Adamus, Milan; Imwensi, O P

2016-03-01

Important hospital-acquired infections include pneumonia, mainly because of the increasing resistance of bacterial pathogens to antimicrobials and the associated potential failure of antibiotic therapy. The present study aimed at determining the most frequent etiological agents of hospital-acquired pneumonia (HAP) and assessing the relationship between 30-day mortality and adequacy of antibiotic therapy. Based on the obtained information, optimal patterns of antibiotic therapy were to be defined, including a pharmacoeconomic perspective. In patients with clinically confirmed HAP, bacterial etiological agents were identified, their susceptibility to antimicrobials was determined and statistical methods were used to assess the relationship between adequacy of antibiotic therapy and 30-day mortality. The study comprised 68 patients with clinically confirmed HAP. The most common etiological agents were strains of Pseudomonas aeruginosa (30.8 %), Klebsiella pneumoniae (23.1 %) and Burkholderia cepacia complex (15.4 %). Gram-negative bacteria accounted for 86.5 % of all bacterial pathogens. The overall mortality reached 42.5 %. In the subgroup of patients with inadequate antibiotic therapy, 30-day mortality was significantly higher (83.3 %) than in the subgroup with adequate therapy (30.0 %; p = 0.002). The risk for 30-day mortality was 2.78 times higher in case of inadequate antibiotic therapy (95%CI: 1.52-5.07). The proportion of Pseudomonas aeruginosa strains was significantly higher in the subgroup of patients with inadequate antibiotic therapy than in those with adequate therapy (67 % vs. 27 %; p = 0.032). Results of the present study suggest a significant relationship between mortality of patients with HAP and ineffective antibiotic therapy due to resistance of the bacterial pathogen. Thus, it is clear that initial antibiotic therapy must be based on qualified assumption of sufficient activity against the most common bacterial pathogens and results of surveillance of bacterial resistance in the relevant epidemiological unit. At the same time, however, it must be stressed that it is impossible to cover all potential variants of the etiological agents and their resistance phenotypes.

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

PubMed

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

2017-01-01

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

Distribution of genes encoding resistance to aminoglycoside modifying enzymes in methicillin-resistant Staphylococcus aureus (MRSA) strains.

PubMed

Khosravi, Azar Dokht; Jenabi, Atefeh; Montazeri, Effat Abbasi

2017-12-01

Today Methicillin-Resistant Staphylococcus aureus (MRSA) have acquired multiple resistance to a wide range of antibiotics including aminoglycosides. So, this study was aimed to investigate the rate of aminoglycoside resistance and the frequency of aminoglycoside resistance mediated genes of aac(Ia)-2, aph(3)-IIIa and ant(4')-Ia among MRSA strains. A total of 467 staphylococci isolates were collected from various clinical samples. S. aureus strains were identified by standard culture and identification criteria and investigating of presence of 16S rRNA and nuc genes. Cefoxitin disk diffusion, and oxacillin-salt agar screening methods were used to detect the MRSA strains with subsequent molecular identification for the presence of mecA gene. Antibiotic susceptibility of MRSA strains against aminoglycoside antibiotics was evaluated by using agar disk diffusion method. Multiplex PCR for the presence of aac(Ia)-2, aph(3)-IIIa and ant(4')-Ia encoding genes for aminoglycosides were performed for MRSA strains. From total staphylococci tested isolates, 262 (56.1%) were identified as S. aureus, of which 161 (61.45%) were detected as MRSA and all comprised mecA gene. The resistance pattern of MRSA strains to aminoglycoside antibiotics were: gentamicin 136 (84.5%); amikacin 125 (77.6%); kanamycin 139 (86.3%); tobramycin 132 (82%); and neomycin 155 (96.3%). The frequency of aac(Ia)-2, aph(3)-IIIa, and ant(4')-Ia genes among MRSA strains, were 64%, 42% and 11.8% respectively. In conclusion, as MRSA strains are of great concern in human infections, the results of present study could provide a useful resource for health sectors for choosing appropriate antibiotics for the effective treatment of infections due to MRSA strains. Copyright © 2017. Published by Elsevier Taiwan.

Soil-borne reservoirs of antibiotic-resistant bacteria are established following therapeutic treatment of dairy calves.

PubMed

Liu, Jinxin; Zhao, Zhe; Orfe, Lisa; Subbiah, Murugan; Call, Douglas R

2016-02-01

We determined if antibiotics residues that are excreted from treated animals can contribute to persistence of resistant bacteria in agricultural environments. Administration of ceftiofur, a third-generation cephalosporin, resulted in a ∼ 3 log increase in ceftiofur-resistant Escherichia coli found in the faeces and pen soils by day 10 (P = 0.005). This resistant population quickly subsided in faeces, but was sustained in the pen soil (∼ 4.5 log bacteria g(-1)) throughout the trial (1 month). Florfenicol treatment resulted in a similar pattern although the loss of florfenicol-resistant E. coli was slower for faeces and remained stable at ∼ 6 log bacteria g(-1) in the soil. Calves were treated in pens where eGFP-labelled E. coli were present in the bedding (∼ 2 log g(-1)) resulting in amplification of the eGFP E. coli population ∼ 2.1 log more than eGFP E. coli populations in pens with untreated calves (day 4; P < 0.005). Excreted residues accounted for > 10-fold greater contribution to the bedding reservoir compared with shedding of resistant bacteria in faeces. Treatment with therapeutic doses of ceftiofur or florfenicol resulted in 2-3 log g(-1) more bacteria than the estimated ID50 (2.83 CFU g(-1)), consistent with a soil-borne reservoir emerging after antibiotic treatment that can contribute to the long-term persistence of antibiotic resistance in animal agriculture. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

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

PubMed

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

2018-04-16

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

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.

Emerge of blaNDM-1 and blaOXA-48-like harboring carbapenem-resistant Klebsiella pneumoniae isolates from hospitalized patients in southwestern Iran.

PubMed

Hosseinzadeh, Zahra; Sedigh Ebrahim-Saraie, Hadi; Sarvari, Jamal; Mardaneh, Jalal; Dehghani, Behzad; Rokni-Hosseini, Seyed Mohammad Hossein; Motamedifar, Mohammad

2018-06-01

One of the most important emerging carbapenem-resistant bacteria is Klebsiella pneumoniae (K. pneumoniae). The present study aimed to investigate the antibiotic susceptibility pattern of K. pneumoniae isolates and detection of carbapenemase producing K. pneumoniae obtained from Iranian hospitalized patients. This cross-sectional study was performed on 211 K. pneumoniae isolates which were recovered from different clinical specimens from 2014 to 2015. Modified Hodge test (MHT) and double disk synergy test (DDST) were done for detection of carbapenemase and metallo-beta-lactamase (MBL) producing K. pneumoniae. The presence of antibiotic resistance determinants was investigated by polymerase chain reaction (PCR) method. The results of antibiotic susceptibility showed that all isolates were resistant to ampicillin, and then mostly resistant to piperacillin and ceftazidime with 76.3% and 66.8%, respectively. On the other hand, the highest sensitivity was toward polymyxin B, followed by carbapenems. Of 29 carbapenem-resistant isolates, all were high-level imipenem-resistant isolates (Minimum inhibitory concentration ≥4), except 4 isolates. The results of MHT and DDST showed that 93.1% (27/29) of carbapenem-resistant isolates were carbapenemase and MBL producing isolates, respectively. The presence of bla NDM-1 and bla OXA-48-like genes was detected in 27 (10.9%) and 2 (0.9%) isolates, respectively. This is the first identification of bla NDM-1 and bla OXA-48-like in K. pneumoniae in Southwestern Iran and the highest reported prevalence of bla NDM in this bacterium from Iran. Since carbapenem-resistant isolates containing New Delhi metallo-beta-lactamase 1 (NDM-1) were almost resistant to all the tested antibiotics, the resistance due to this gene may be increased in the near future as a potential health threat. Copyright © 2017. Published by Elsevier Taiwan LLC.

The determinants of the antibiotic resistance process

PubMed Central

Franco, Beatriz Espinosa; Altagracia Martínez, Marina; Sánchez Rodríguez, Martha A; Wertheimer, Albert I

2009-01-01

Background: The use of antibiotic drugs triggers a complex interaction involving many biological, sociological, and psychological determinants. Resistance to antibiotics is a serious worldwide problem which is increasing and has implications for morbidity, mortality, and health care both in hospitals and in the community. Objectives: To analyze current research on the determinants of antibiotic resistance and comprehensively review the main factors in the process of resistance in order to aid our understanding and assessment of this problem. Methods: We conducted a MedLine search using the key words “determinants”, “antibiotic”, and “antibiotic resistance” to identify publications between 1995 and 2007 on the determinants of antibiotic resistance. Publications that did not address the determinants of antibiotic resistance were excluded. Results: The process and determinants of antibiotic resistance are described, beginning with the development of antibiotics, resistance and the mechanisms of resistance, sociocultural determinants of resistance, the consequences of antibiotic resistance, and alternative measures proposed to combat antibiotic resistance. Conclusions: Analysis of the published literature identified the main determinants of antibiotic resistance as irrational use of antibiotics in humans and animal species, insufficient patient education when antibiotics are prescribed, lack of guidelines for treatment and control of infections, lack of scientific information for physicians on the rational use of antibiotics, and lack of official government policy on the rational use of antibiotics in public and private hospitals. PMID:21694883

Surveillance of antibiotic resistance in Neisseria gonorrhoeae in the WHO Western Pacific and South East Asian regions, 2007-2008.

PubMed

Tapsall, J W; Limnios, E A; Abu Bakar, Hjh Mahani Hj; Darussalam, Brunei; Ping, Yin Yue; Buadromo, E M; Kumar, P; Singh, S; Lo, J; Bala, M; Risbud, A; Deguchi, T; Tanaka, M; Watanabe, Y; Lee, K; Chong, Y; Noikaseumsy, S; Phouthavane, T; Sam, I-Ching; Tundev, O; Lwin, K M; Eh, P H; Goarant, C; Goursaud, R; Bathgate, T; Brokenshire, M; Latorre, L; Velemu, E; Carlos, C; Leano, S; Telan, E O; Goh, S S; Koh, S T; Ngan, C; Tan, A L; Mananwatte, S; Piyanoot, N; Lokpichat, S; Sirivongranson, P; Fakahau, M; Sitanilei, H; Hung, Le Van

2010-03-01

Long-term surveillance of antimicrobial resistance in Neisseria gonorrhoeae has been conducted in the World Health Organization (WHO) Western Pacific Region (WPR) to optimise antibiotic treatment of gonococcal disease since 1992. In 2007 and 2008, this Gonococcal Antimicrobial Surveillance Programme (GASP) was enhanced by the inclusion of data from the South East Asian Region (SEAR) and recruitment of additional centres within the WPR. Approximately 17,450 N. gonorrhoeae were examined for their susceptibility to one or more antibiotics used for the treatment of gonorrhoea by external quality controlled methods in 24 reporting centres in 20 countries and/or jurisdictions. A high proportion of penicillin and/or quinolone resistance was again detected amongst isolates tested in North Asia and the WHO SEAR, but much lower rates of penicillin resistance and little quinolone resistance was present in most of the Pacific Island countries. The proportion of gonococci reported as 'resistant', 'less susceptible' or 'non-susceptible' gonococci to the third-generation cephalosporin antibiotic ceftriaxone lay in a wide range, but no major changes were evident in cephalosporin minimal inhibitory concentration (MIC) patterns in 2007-2008. Altered cephalosporin susceptibility was associated with treatment failures following therapy with oral third-generation cephalosporins. There is a need for revision and clarification of some of the in vitro criteria that are currently used to categorise the clinical importance of gonococci with different ceftriaxone and oral cephalosporin MIC levels. The number of instances of spectinomycin resistance remained low. A high proportion of strains tested continued to exhibit a form of plasmid mediated high level resistance to tetracyclines. The continuing emergence and spread of antibiotic resistant gonococci in and from the WHO WPR and SEAR supports the need for gonococcal antimicrobial resistance surveillance programs such as GASP to be maintained and potentially expanded.

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

PubMed Central

Kasuya, Morimasa

1964-01-01

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

Determination of antimicrobial and heavy metal resistance profiles of some bacteria isolated from aquatic amphibian and reptile species.

PubMed

Hacioglu, Nurcihan; Tosunoglu, Murat

2014-01-01

The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from aquatic animals (Lissotriton vulgaris, Pelophylax ridibundus, Emys orbicularis, Mauremys rivulata, and Natrix natrix) in Turkey (Kavak Delta). A total of 153 bacteria have been successfully isolated from cloaca and oral samples of the aquatic amphibians and reptilians which were found, namely, Aeromonas sp. (n = 29), Plesiomonas sp. (n = 7), Vibrio sp. (n = 12), Citrobacter sp. (n = 12), Enterobacter sp. (n = 11), Escherichia sp. (n = 22), Klebsiella sp. (n = 22), Edwardsiella sp. (n = 6), Hafnia sp. (n = 1), Proteus sp. (n = 19), Providencia sp. (n = 8), and Pseudomonas sp. (n = 4). In terms of antibiotic and heavy metal susceptibility testing, each isolate was tested against 12 antibiotics and 4 metals. There was a high incidence of resistance to cefoxitin (46.40 %), ampicillin (44.44 %), erythromycin (35.29 %), and a low incidence of resistance to gentamicin (6.53 %), kanamycin (8.49 %), chloramphenicol (9.15 %), and cefotaxime (10.45 %). The multiple antibiotic resistance index of each bacterial species indicated that bacteria from raised amphibians and reptiles have been exposed to tested antibiotics, with results ranging from 0 to 0.58. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from100 to >3,200 μg/mL. According to these results, a significant occurrence of bacteria in the internal organs of reptiles and amphibians, with a high incidence of resistance against antibiotics and heavy metals, may risk aquatic animals and the public health. These data appoint the importance of epidemiological surveillance and microbiological monitoring and reinforce the need to implement environment protection programs for amphibian and reptile species.

Overview: Global and Local Impact of Antibiotic Resistance.

PubMed

Watkins, Richard R; Bonomo, Robert A

2016-06-01

The rapid and ongoing spread of antibiotic resistance poses a serious threat to global public health. The indiscriminant use of antibiotics in agriculture and human medicine along with increasingly connected societies has fueled the distribution of antibiotic-resistant bacteria. These factors together have led to rising numbers of infections caused by multidrug-resistant and pan-resistant bacteria, with increases in morbidity and mortality. This article summarizes the trends in antibiotic resistance, discusses the impact of antibiotic resistance on society, and reviews the use of antibiotics in agriculture. Feasible ways to tackle antibiotic resistance to avert a post-antibiotic era are suggested. Copyright © 2016 Elsevier Inc. All rights reserved.

Parallel Evolution of High-Level Aminoglycoside Resistance in Escherichia coli Under Low and High Mutation Supply Rates.

PubMed

Ibacache-Quiroga, Claudia; Oliveros, Juan C; Couce, Alejandro; Blázquez, Jesus

2018-01-01

Antibiotic resistance is a major concern in public health worldwide, thus there is much interest in characterizing the mutational pathways through which susceptible bacteria evolve resistance. Here we use experimental evolution to explore the mutational pathways toward aminoglycoside resistance, using gentamicin as a model, under low and high mutation supply rates. Our results show that both normo and hypermutable strains of Escherichia coli are able to develop resistance to drug dosages > 1,000-fold higher than the minimal inhibitory concentration for their ancestors. Interestingly, such level of resistance was often associated with changes in susceptibility to other antibiotics, most prominently with increased resistance to fosfomycin. Whole-genome sequencing revealed that all resistant derivatives presented diverse mutations in five common genetic elements: fhuA, fusA and the atpIBEFHAGDC, cyoABCDE , and potABCD operons. Despite the large number of mutations acquired, hypermutable strains did not pay, apparently, fitness cost. In contrast to recent studies, we found that the mutation supply rate mainly affected the speed (tempo) but not the pattern (mode) of evolution: both backgrounds acquired the mutations in the same order, although the hypermutator strain did it faster. This observation is compatible with the adaptive landscape for high-level gentamicin resistance being relatively smooth, with few local maxima; which might be a common feature among antibiotics for which resistance involves multiple loci.

Parallel Evolution of High-Level Aminoglycoside Resistance in Escherichia coli Under Low and High Mutation Supply Rates

PubMed Central

Ibacache-Quiroga, Claudia; Oliveros, Juan C.; Couce, Alejandro; Blázquez, Jesus

2018-01-01

Antibiotic resistance is a major concern in public health worldwide, thus there is much interest in characterizing the mutational pathways through which susceptible bacteria evolve resistance. Here we use experimental evolution to explore the mutational pathways toward aminoglycoside resistance, using gentamicin as a model, under low and high mutation supply rates. Our results show that both normo and hypermutable strains of Escherichia coli are able to develop resistance to drug dosages > 1,000-fold higher than the minimal inhibitory concentration for their ancestors. Interestingly, such level of resistance was often associated with changes in susceptibility to other antibiotics, most prominently with increased resistance to fosfomycin. Whole-genome sequencing revealed that all resistant derivatives presented diverse mutations in five common genetic elements: fhuA, fusA and the atpIBEFHAGDC, cyoABCDE, and potABCD operons. Despite the large number of mutations acquired, hypermutable strains did not pay, apparently, fitness cost. In contrast to recent studies, we found that the mutation supply rate mainly affected the speed (tempo) but not the pattern (mode) of evolution: both backgrounds acquired the mutations in the same order, although the hypermutator strain did it faster. This observation is compatible with the adaptive landscape for high-level gentamicin resistance being relatively smooth, with few local maxima; which might be a common feature among antibiotics for which resistance involves multiple loci. PMID:29615988

Antibiotic susceptibility, heteroresistance, and updated treatment strategies in Helicobacter pylori infection.

PubMed

Mascellino, Maria Teresa; Porowska, Barbara; De Angelis, Massimiliano; Oliva, Alessandra

2017-01-01

In this review, we discuss the problem of antibiotic resistance, heteroresistance, the utility of cultures and antibiotic susceptibility tests in Helicobacter pylori ( Hp ) eradication, as well as the updated treatment strategies for this infection. The prevalence of antibiotic resistance is increasing all over the world, especially for metronidazole and clarithromycin, because of their heavy use in some geographical areas. Heteroresistance (simultaneous presence of both susceptible and resistant strains in different sites of a single stomach) is another important issue, as an isolate could be mistakenly considered susceptible if a single biopsy is used for antimicrobial tests. We also examined literature data regarding eradication success rates of culture-guided and empiric therapies. The empiric therapy and the one based on susceptibility testing, in Hp eradication, may depend on several factors such as concomitant diseases, the number of previous antibiotic treatments, differences in bacterial virulence in individuals with positive or negative cultures, together with local antibiotic resistance patterns in real-world settings. Updated treatment strategies in Hp infection presented in the guidelines of the Toronto Consensus Group (2016) are reported. These suggest to prolong eradication therapy up to 14 days, replacing the old triple therapy with a quadruple therapy based on proton pump inhibitor (PPI), bismuth, metronidazole, and tetracycline for most of the patients, or as an alternative quadruple therapy without bismuth, based on the use of PPI, amoxicillin, metronidazole, and clarithromycin. The new drug vonoprazan, a first-in-class potassium-competitive acid blocker recently approved in Japan, is also considered to be a promising solution for Hp eradication, even for clarithromycin-resistant strains. Furthermore, there is growing interest in finding new therapeutic strategies, such as the development of vaccines or the use of natural resources, including probiotics, plants, or nutraceuticals.

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

PubMed

Wang, Jing; Wei, Xinyuan; Fan, Mingtao

2018-06-01

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

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

PubMed

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

2014-01-01

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

International Comparison of Causative Bacteria and Antimicrobial Susceptibilities of Urinary Tract Infections between Kobe, Japan, and Surabaya, Indonesia.

PubMed

Kitagawa, Koichi; Shigemura, Katsumi; Yamamichi, Fukashi; Alimsardjono, Lindawati; Rahardjo, Dadik; Kuntaman, Kuntaman; Shirakawa, Toshiro; Fujisawa, Masato

2018-01-23

Variation by country in urinary tract infection (UTI)-causative bacteria is partly due to the differences in the use of antibiotics. We compared their frequencies and antibiotic susceptibilities in the treatment of patients with UTI from 2 cities, Kobe, Japan, and Surabaya, Indonesia. We retrospectively analyzed 1,804 urine samples collected from patients with UTI in 2014 (1,251 collected in 11 months at Kobe University Hospital in Kobe and 544 collected in 2 months at Dr. Soetomo Hospital in Surabaya). Surabaya data were divided into adult and pediatric patients because a substantial number of specimens from pediatric-patients had been collected. The results indicated that Escherichia coli was the most common uropathogen (24.1% in Kobe and 39.3% in Surabaya) and was significantly resistant to ampicillin and substantially to first- and third-generation cephalosporins in Surabaya adults but not in Kobe adults (p ＜ 0.01). Enterococcus faecalis was often isolated in Kobe (14.0%), but not in Surabaya (5.3%). Klebsiella spp. were isolated at a higher rate in Surabaya pediatric patients (20.3%) than in Surabaya adults (13.6%) and Kobe adults (6.6%). The antibiotic susceptibilities of the isolates form Surabaya isolates tended to be lower than the ones from Kobe. Extended-spectrum β-lactamase-producing Gram-negative bacteria were detected at a significantly higher rate in Surabaya than in Kobe (p ＜ 0.001). These results showed that the antimicrobial resistance patterns of UTI-causative bacteria are highly variable among 2 countries, and the continuous surveillance of trends in antibiotic resistance patterns of uropathogens is necessary for the future revision of antibiotic use.

Isolation, Biochemical and Molecular Identification, and In-Vitro Antimicrobial Resistance Patterns of Bacteria Isolated from Bubaline Subclinical Mastitis in South India.

PubMed

Preethirani, P L; Isloor, Shrikrishna; Sundareshan, S; Nuthanalakshmi, V; Deepthikiran, K; Sinha, Akhauri Y; Rathnamma, D; Nithin Prabhu, K; Sharada, R; Mukkur, Trilochan K; Hegde, Nagendra R

2015-01-01

Buffaloes are the second largest source of milk. Mastitis is a major impediment for milk production, but not much information is available about bubaline mastitis, especially subclinical mastitis. The aim of this study was to (a) investigate the application of various tests for the diagnosis of bubaline subclinical mastitis, (b) identify the major bacteria associated with it, and (c) evaluate the antibiotic resistance pattern of the bacteria. To this end, 190 quarter milk samples were collected from 57 domesticated dairy buffaloes from organized (64 samples) and unorganized (126 samples) sectors. Of these, 48.4%, 40.0%, 45.8%, 61.1%, and 61.6% were positive for subclinical mastitis by somatic cell count, electrical conductivity, California mastitis test, bromothymol blue test, and N-acetyl glucosaminidase test, respectively. As compared to the gold standard of somatic cell count, California mastitis test performed the best. However, a combination of the two methods was found to be the best option. Microbiological evaluation, both by biochemical methods as well as by monoplex and multiplex polymerase chain reaction, revealed that coagulase-negative staphylococci were the most predominant (64.8%) bacteria, followed by streptococci (18.1%), Escherichia coli (9.8%) and Staphylococcus aureus (7.3%). Most of the pathogens were resistant to multiple antibiotics, especially to β-lactam antibiotics. We propose that California mastitis test be combined with somatic cell count for diagnosis of subclinical mastitis in domestic dairy buffaloes. Further, our results reveal high resistance of the associated bacteria to the β-lactam class of antibiotics, and a possible major role of coagulase-negative staphylococci in causing the disease in India.

[Surveillance of healthcare associated infections, bacterial resistance and antibiotic consumption in high-complexity hospitals in Colombia, 2011].

PubMed

Villalobos, Andrea Patricia; Barrero, Liliana Isabel; Rivera, Sandra Milena; Ovalle, María Victoria; Valera, Danik

2014-04-01

Preventing healthcare associated infections, especially for resistant microorganisms, is a priority. In Colombia, the surveillance of such events was started through a national pilot study. To describe the epidemiology of device-associated infections, bacterial resistance and antibiotic consumption patterns in institutions with intensive care units (ICU), 2011. Descriptive observational study in 10 health institutions from three Colombian provinces: Antioquia, Valle del Cauca, and Bogotá. Surveillance protocols were designed and implemented by trained health professionals in each hospital. A web tool was designed for data reporting and analysis. Infection rates, device-use percentages and antibiotics defined daily dose (DDD) were calculated. Bacterial resistance phenotypes and profiles were reported and analyzed using Whonet 5.6. The most common event was bloodstream infection (rate > 4.8/1000 catheter-days) followed by ventilator-associated pneumonia (VAP) and catheter-related urinary tract infection, showing a wide variability among institutions. A high consumption of meropenem in the ICU (DDD 22.5/100 beds-day) was observed, as well as a high carbapenem resistance (> 11.6%) and a high frequency of third generation cephalosporins resistance (> 25.6%) in Enterobacteriaceae in ICUs and hospitalization wards. The percentage of methicillin-resistant Staphylococcus aureus was higher in hospitalization wards (34.3%). This is the first experience in measuring these events in Colombia. It is necessary to implement a national surveillance system aimed at guiding governmental and institutional actions oriented to infection prevention and control, to resistance management and to the promotion of antibiotics rational use, along with a follow-up and monitoring process.

Methicillin-resistant Staphylococcus aureus producing Panton-Valentine leukocidin in a retrospective case series from 12 French hospital laboratories, 2000-2003.

PubMed

Robert, J; Etienne, J; Bertrand, X

2005-07-01

A retrospective analysis of hospital laboratory databases for 2000-2003 found that 0.4-1.0% of methicillin-resistant Staphylococcus aureus isolates had an antibiotic susceptibility pattern associated previously with the production of Panton-Valentine leukocidin (PVL). Of 81 isolates of this type, 35 were available for molecular testing. Each of the 35 available isolates carried the PVL genes, and 33 of these 35 isolates had an identical SmaI pulsed-field gel electrophoresis pattern.

Prevalence and resistance patterns of commensal S. aureus in community-dwelling GP patients and socio-demographic associations. A cross-sectional study in the framework of the APRES-project in Austria.

PubMed

Hoffmann, Kathryn; den Heijer, Casper D J; George, Aaron; Apfalter, Petra; Maier, Manfred

2015-05-16

The aim of the present study was to assess the prevalence and resistance of commensal S. aureus in the nasal microbiota of community-dwelling persons in Austria, as well as to identify possible associations with socio-demographic factors. Multi-drug resistance in this population was additionally studied. This cross-sectional study was conducted within the context of the European APRES project. In nine European countries, nasal swabs were collected from 32,206 general practice patients who received care for non-infectious reasons. In Austria, 20 GPs attempted to recruit 200 consecutive patients without infectious diseases, with each patient completing demographic questionnaires as well as providing a nose swab sample. Isolation, identification, and resistance testing of S. aureus were performed. Statistical analyses included subgroup analyses and logistic regression models. 3309 nose swabs and corresponding questionnaires from Austrian subjects were analyzed. S. aureus was identified in 16.6 % (n = 549) of nose swabs, of which 70.1 % were resistant against one or more antibiotics, mainly penicillin. S. aureus carrier status was significantly associated with male sex (OR 1.6; 1.3-2.0), younger age (OR 1.3; 1.0-1.8), living in a rural area (OR 1.4; 1.1-1.7) and working in the healthcare sector (OR 1.5; 1.0-2.1). Multi-drug resistances were identified in 13.7 % (n = 75) of the S. aureus carriers and 1.5 % (n = 8) tested positive for MRSA. The highest resistance rate was observed against penicillin (64.8 %), followed by azithromycin (13.5 %) and erythromycin with 13.3 %. This study describes the prevalence and resistance patterns of commensal S. aureus in community-dwelling persons in Austria and shows that differences exist between socio-demographic groups. Demographic associations have been found for S. aureus carriers but not for carriers of resistant S. aureus strains. Only two thirds of S. aureus strains were found to be resistant against small spectrum penicillin. As it is recognized that one of the corner stones for the containment of antibiotic resistance is the appropriate prescription of antibiotics in the outpatient sector, this finding lends support to the avoidance of prescription of broad-spectrum antibiotics to treat S. aureus infections in the community.

[Considerations on the antibiotic activity (M.I.C.) revealed in 247 serotypes of Salmonella].

PubMed

Pitzus, E; Peretti, P; Ghinelli, P; Bisicchia, R; Turano, A

1975-01-01

247 strains of Salmonella, isolated in Brescia province duriing 1973-1974 have been typed by serological methods. The MIC has been determined, using the following antibiotics: chloramphenicol, tetracycline HCL, ampicillin, doxycycline, rifampicin, cephazolin, carbenicillin, nifuratel, gentamicin, aminosidine, trimetho-prim-sulphamethoazole, nalidixic acid. The pattern of resistence of the various serotypes is quite constant. The relationship between diffusion and epidermiological factors are discussed.

Antibiotic Resistance in Haemophilus influenzae Decreased, except for β-Lactamase-Negative Amoxicillin-Resistant Isolates, in Parallel with Community Antibiotic Consumption in Spain from 1997 to 2007▿

PubMed Central

García-Cobos, Silvia; Campos, José; Cercenado, Emilia; Román, Federico; Lázaro, Edurne; Pérez-Vázquez, María; de Abajo, Francisco; Oteo, Jesús

2008-01-01

The susceptibility to 14 antimicrobial agents and the mechanisms of aminopenicillin resistance were studied in 197 clinical isolates of Haemophilus influenzae—109 isolated in 2007 (study group) and 88 isolated in 1997 (control group). Community antibiotic consumption trends were also examined. H. influenzae strains were consecutively isolated from the same geographic area, mostly from respiratory specimens from children and adults. Overall, amoxicillin resistance decreased by 8.4% (from 38.6 to 30.2%). β-Lactamase production decreased by 15.6% (from 33 to 17.4%, P = 0.01), but amoxicillin resistance without β-lactamase production increased by 7.1% (from 5.7 to 12.8%). All β-lactamase-positive isolates were TEM-1, but five different promoter regions were identified, with Pdel being the most prevalent in both years, and Prpt being associated with the highest amoxicillin resistance. A new promoter consisting of a double repeat of 54 bp was detected. Community consumption of most antibiotics decreased, as did the geometric means of their MICs, but amoxicillin-clavulanic acid and azithromycin consumption increased by ca. 60%. For amoxicillin-clavulanic acid, a 14.2% increase in the population with an MIC of 2 to 4 μg/ml (P = 0.02) was observed; for azithromycin, a 21.2% increase in the population with an MIC of 2 to 8 μg/ml (P = 0.0005) was observed. In both periods, the most common gBLNAR (i.e., H. influenzae isolates with mutations in the ftsI gene as previously defined) patterns were IIc and IIb. Community consumption of trimethoprim-sulfamethoxazole decreased by 54%, while resistance decreased from 50 to 34.9% (P = 0.04). Antibiotic resistance in H. influenzae decreased in Spain from 1997 to 2007, but surveillance should be maintained since new forms of resistances may be developing. PMID:18505850

Fighting antibiotic resistance in the intensive care unit using antibiotics.

PubMed

Plantinga, Nienke L; Wittekamp, Bastiaan H J; van Duijn, Pleun J; Bonten, Marc J M

2015-01-01

Antibiotic resistance is a global and increasing problem that is not counterbalanced by the development of new therapeutic agents. The prevalence of antibiotic resistance is especially high in intensive care units with frequently reported outbreaks of multidrug-resistant organisms. In addition to classical infection prevention protocols and surveillance programs, counterintuitive interventions, such as selective decontamination with antibiotics and antibiotic rotation have been applied and investigated to control the emergence of antibiotic resistance. This review provides an overview of selective oropharyngeal and digestive tract decontamination, decolonization of methicillin-resistant Staphylococcus aureus and antibiotic rotation as strategies to modulate antibiotic resistance in the intensive care unit.

Nosocomial pneumonia.

PubMed

Myrianthefs, Pavlos M; Kalafati, Maria; Samara, Irini; Baltopoulos, George J

2004-01-01

Nosocomial pneumonia (NP) is defined as pneumonia that develops within 48 hours or more of hospital admission and which was not developing at the time of admission. Nosocomial pneumonia, also known as hospital-acquired pneumonia (HAP), is the second most common hospital infection, while ventilator-associated pneumonia represents the most common intensive care unit (ICU) infection. Nosocomial pneumonia significantly contributes to morbidity, mortality, and escalating healthcare costs because of increases in antibiotic prescription and administration, length of ICU stay, and length of hospital stay. Aspiration and colonization of the upper respiratory tract seem to be the major pathogenetic mechanisms for the development of NP, either in intubated or spontaneously breathing patients. The microbiology of NP depends on the timing of onset. In early-onset NP, the responsible pathogens are generally endogenous community-acquired pathogens. In late-onset NP, the responsible microbes include potentially multi-drug-resistant nosocomial organisms residing in oropharyngeal or gastric contents. Important risk factors for development of NP include coma, intubation, prolonged mechanical ventilation, repeated intubations, supine positioning, and long-term antibiotic use. The most significant preventive measures include routine hand washing and avoidance of (1) the supine position, (2) inappropriate antibiotics, and (3) overuse of H2-antagonists for stress ulcer prophylaxis. Accurate diagnosis of NP is difficult and controversial, warranting consideration for the application of invasive quantitative culture techniques over tracheal aspirates. Empiric antibiotic treatment should be prompt, starting on clinical suspicion, and based on local ICU pathogen epidemiology and antibiotic resistance patterns and on a deescalating antibiotic strategy. Innovative antibiotic strategies, such as antibiotic rotation, to help prevent the emergence of multi-drug-resistant pathogens and improve survival should be considered.

Distribution and quantification of antibiotic resistant genes and bacteria across agricultural and non-agricultural metagenomes.

PubMed

Durso, Lisa M; Miller, Daniel N; Wienhold, Brian J

2012-01-01

There is concern that antibiotic resistance can potentially be transferred from animals to humans through the food chain. The relationship between specific antibiotic resistant bacteria and the genes they carry remains to be described. Few details are known about the ecology of antibiotic resistant genes and bacteria in food production systems, or how antibiotic resistance genes in food animals compare to antibiotic resistance genes in other ecosystems. Here we report the distribution of antibiotic resistant genes in publicly available agricultural and non-agricultural metagenomic samples and identify which bacteria are likely to be carrying those genes. Antibiotic resistance, as coded for in the genes used in this study, is a process that was associated with all natural, agricultural, and human-impacted ecosystems examined, with between 0.7 to 4.4% of all classified genes in each habitat coding for resistance to antibiotic and toxic compounds (RATC). Agricultural, human, and coastal-marine metagenomes have characteristic distributions of antibiotic resistance genes, and different bacteria that carry the genes. There is a larger percentage of the total genome associated with antibiotic resistance in gastrointestinal-associated and agricultural metagenomes compared to marine and Antarctic samples. Since antibiotic resistance genes are a natural part of both human-impacted and pristine habitats, presence of these resistance genes in any specific habitat is therefore not sufficient to indicate or determine impact of anthropogenic antibiotic use. We recommend that baseline studies and control samples be taken in order to determine natural background levels of antibiotic resistant bacteria and/or antibiotic resistance genes when investigating the impacts of veterinary use of antibiotics on human health. We raise questions regarding whether the underlying biology of each type of bacteria contributes to the likelihood of transfer via the food chain.

Evaluation of Aminoglycoside and Carbapenem Resistance in a Collection of Drug-Resistant Pseudomonas aeruginosa Clinical Isolates.

PubMed

Holbrook, Selina Y L; Garneau-Tsodikova, Sylvie

2017-12-20

Pseudomonas aeruginosa, a Gram-negative bacterium, is a member of the ESKAPE pathogens and one of the leading causes of healthcare-associated infections worldwide. Aminoglycosides (AGs) are recognized for their efficacy against P. aeruginosa. The most common resistance mechanism against AGs is the acquisition of AG-modifying enzymes (AMEs) by the bacteria, including AG N-acetyltransferases (AACs), AG O-phosphotransferases (APHs), and AG O-nucleotidyltransferases (ANTs). In this study, we obtained 122 multidrug-resistant P. aeruginosa clinical isolates and evaluated the antibacterial effects of six AGs and two carbapenems alone against all clinical isolates, and in combination against eight selected strains. We further probed for four representatives of the most common AME genes [aac(6')-Ib, aac(3)-IV, ant(2")-Ia, and aph(3')-Ia] by polymerase chain reaction (PCR) and compared the AME patterns of these 122 clinical isolates to their antibiotic resistance profile. Among the diverse antibiotics resistance profile displayed by these clinical isolates, we found correlations between the resistance to various AGs as well as between the resistance to one AG and the resistance to carbapenems. PCR results revealed that the presence of aac(6')-Ib renders these isolates more resistant to a variety of antibiotics. The correlation between resistance to various AGs and carbapenems partially reflects the complex resistance strategies adapted in these pathogens and encourages the development of strategic treatment for each P. aeruginosa infection by considering the genetic information of each isolated bacteria.

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

PubMed

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

2017-09-06

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

Antibiotic resistance and pathogenicity factors in Staphylococcus aureus isolated from mastitic Sahiwal cattle.

PubMed

Kumar, Ravinder; Yadav, B R; Singh, R S

2011-03-01

Methicillin-resistant Staphylococcus aureus (MRSA) poses a serious problem in dairy animals suffering from mastitis. In the present study, the distribution of mastitic MRSA and antibiotic resistance was studied in 107 strains of S. aureus isolated from milk samples from 195 infected udders. The characterizations pathogenic factors (adhesin and toxin genes) and antibiotic susceptibility of isolates were carried out using gene amplification and disc diffusion assays, respectively. A high prevalence of MRSA was observed in the tested isolates (13.1%). The isolates were also highly resistant to antibiotics, i.e. 36.4% were resistant to streptomycin, 33.6% to oxytetracycline, 29.9% to gentamicin and 26.2% each to chloramphenicol, pristinomycin and ciprofloxacin. A significant variation in the expression of pathogenic factors (Ig, coa and clf) was observed in these isolates. The overall distribution of adhesin genes ebp, fib, bbp, fnbB, cap5, cap8, map and cna in the isolates was found to be 69.1, 67.2, 6.5, 20.5, 60.7, 26.1, 81.3 and 8.4%, respectively. The presence of fib, fnbB, bbp and map genes was considerably greater in MRSA than in methicillin-susceptible S. aureus (MSSA) isolates. The proportions of toxin genes, namely, hlb, seb, sec, sed, seg and sei, in the isolates were found to be 94.3, 0.9, 8.4, 0.9, 10.2 and 49.5%, respectively. The proportions of agr genes I, II, III and IV were found to be 39.2, 27.1, 21.5 and 12.1%, respectively. A few isolates showed similar antibiotic-resistance patterns, which could be due to identical strains or the dissemination of the same strains among animals. These findings can be utilized in mastitis treatment programmes and antimicrobials strategies in organized herd.

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

PubMed

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

2014-07-01

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

The distribution of beta lactamase genes in Escherichia coli phylotypes isolated from diarrhea and UTI cases in northwest Iran.

PubMed

Hemati, Zahra; Ghanbarpour, Reza; Alizade, Hesam

2014-01-01

Pathogenic Escherichia coli strains are a common cause of intestinal and extra-intestinal infections, especially in developing countries. Extended spectrum beta-lactamases (ESBLS), a heterogeneous group of plasmid-encoded beta-lactamases, are common throughout the world. The aim of the present study was to determine the phenotypic and genotypic characteristics of ESBLS produced by E. coli isolates taken from patients with diarrhea and urinary tract infections (UTI) in northwest Iran. A total of 132 E. coli isolates (92 isolates from UTI and 40 isolates from diarrheic cases) were recovered and confirmed by biochemical tests. The isolates were examined for blaTEM and blaSHV genes and phylogenetic background by two multiplex PCR assays. The isolates were tested for antibiotic susceptibility against nine antibiotic agents by the disk diffusion method. The phylogenetic analysis showed that the UTI isolates mostly fell into phylo-group B2, followed by D, while the diarrheic isolates belonged to phylo-groups D and A. Out of 92 UTI isolates, 29.3% and 17.4% possessed blaTEM and blaSHV genes, respectively. Ten diarrheic isolates were positive for blaTEM, two isolates possessed the blaSHV gene, and one isolate was positive for both genes. The UTI isolates that were positive for blaTEM and blaSHV genes mostly belonged to phylo-groups D and B2, whereas the diarrhea isolates were in phylo-groups D and A. Phylogenetic group D isolates have an accumulation of ESBLS genes in the diarrheic and UTI isolates. In both the UTI and diarrhea isolates, the maximum rate of resistance was against cefazolin, and the minimum rate of resistance was against nitrofurantoin. Twenty-four antibiotic resistance patterns were observed among the isolates. The amikacin, ciprofloxacin, cefotaxime, cefuroxime, cefazolin, gentamicin, nalidixic acid and trimethoprim/sulfamethoxazole resistance pattern was the most prevalent in the isolates that belonged to phylo-group D. The correct choice of effective antibiotic policy is needed to limit the spread of antibiotic resistance in bacteria.

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

Clinical and economic impact of an antibiotics stewardship programme in a regional hospital in Hong Kong.

PubMed

Ng, C K; Wu, T C; Chan, W M J; Leung, Y S W; Li, C K P; Tsang, D N C; Leung, G M

2008-10-01

Inappropriate use of antibiotics is one of the important factors attributing to emergence of drug-resistant pathogens. Infection with multidrug-resistant pathogens adversely affects quality of medical care. Queen Elizabeth Hospital, an 1800-bed acute service hospital in Hong Kong. Antibiotics are commonly prescribed for treating acute infections. Reduce inappropriate prescription of broad-spectrum antibiotics and overall antibiotic prescription through implementation of a multidisciplinary antibiotics stewardship programme (ASP). A multidisciplinary programme involving policy and guideline formulation, education and feedback, monthly antibiotic consumption and cost monitoring, antimicrobial susceptibility pattern reporting and concurrent feedbacks for commonly prescribed broad-spectrum antibiotics was implemented in 2004. Predefined logistics to prescribe "restricted" antibiotics were formulated and implemented with collaborative efforts from clinical and non-clinical departments. The programme was supported by management at department and hospital levels. Broad-spectrum antibiotics were prescribed inappropriately in 28.9% (n = 192) clinical scenarios. The ASP reduced the restricted and total antibiotic consumption as well as the antibiotics-related costs. Predefined clinical outcomes were not adversely affected. Economic analysis suggested that the extra human cost in running ASP could be offset by savings from antibiotic expenditure. It is cost-effective to implement a multidisciplinary ASP in acute service hospitals as the programme reduces antibiotic consumption and results in overall cost savings. The quality of medical care is not jeopardized as the important clinical outcomes are not adversely affected. The generalisability and sustainability of ASPs in other clinical contexts warrant further studies to ensure the continuous success of this programme.

Prevalence and antibiogram study of Salmonella and Staphylococcus aureus in poultry meat

PubMed Central

Akbar, Ali; Anal, Anil Kumar

2013-01-01

Objective To evaluate the presence and antibiogram pattern of Salmonella and Staphylococcus aureus (S. aureus) in retail poultry meat products. Methods Foodborne pathogens (Salmonella and S. aureus) were isolated from poultry meat and confirmed with the help of biochemical and immunological test. Antibiogram of the isolates were examined by following CLSI methods. Results A total number of 209 poultry meat samples were collected and studied in this study. Out of which, 5.26% were found contaminated with Salmonella while 18.18% were found contaminated with S. aureus. All the Salmonella and S. aureus isolates were found resistant to at least one antibiotic. About 72.72% of the Salmonella isolates showed resistance to tetracycline, while S. aureus isolates were also found highly resistant to tetracycline equal to 44.73%. One of the Salmonella isolates showed multi-drug resistance to almost six antibiotics out of nine antibiotics used in the study. Multidrug resistant S. aureus isolates were also found in the study. Conclusions The study confirmed the presence of Salmonella and S. aureus in retail poultry meat. It is a potential threat to consumer health. To reduce the risk of contamination, good hygiene practices are necessary from processing to storage. PMID:23593598

Assessing potential human health hazards and benefits from subtherapeutic antibiotics in the United States: tetracyclines as a case study.

PubMed

Cox, Louis Anthony Tony; Popken, Douglas A

2010-03-01

Many scientists, activists, regulators, and politicians have expressed urgent concern that using antibiotics in food animals selects for resistant strains of bacteria that harm human health and bring nearer a "postantibiotic era" of multidrug resistant "super-bugs." Proposed political solutions, such as the Preservation of Antibiotics for Medical Treatment Act (PAMTA), would ban entire classes of subtherapeutic antibiotics (STAs) now used for disease prevention and growth promotion in food animals. The proposed bans are not driven by formal quantitative risk assessment (QRA), but by a perceived need for immediate action to prevent potential catastrophe. Similar fears led to STA phase-outs in Europe a decade ago. However, QRA and empirical data indicate that continued use of STAs in the United States has not harmed human health, and bans in Europe have not helped human health. The fears motivating PAMTA contrast with QRA estimates of vanishingly small risks. As a case study, examining specific tetracycline uses and resistance patterns suggests that there is no significant human health hazard from continued use of tetracycline in food animals. Simple hypothetical calculations suggest an unobservably small risk (between 0 and 1.75E-11 excess lifetime risk of a tetracycline-resistant infection), based on the long history of tetracycline use in the United States without resistance-related treatment failures. QRAs for other STA uses in food animals also find that human health risks are vanishingly small. Whether such QRA calculations will guide risk management policy for animal antibiotics in the United States remains to be seen.

Investigating Undergraduate Students' Use of Intuitive Reasoning and Evolutionary Knowledge in Explanations of Antibiotic Resistance.

PubMed

Richard, Melissa; Coley, John D; Tanner, Kimberly D

2017-01-01

Natural selection is a central concept throughout biology; however, it is a process frequently misunderstood. Bacterial resistance to antibiotic medications provides a contextual example of the relevance of evolutionary theory and is also commonly misunderstood. While research has shed light on student misconceptions of natural selection, minimal study has focused on misconceptions of antibiotic resistance. Additionally, research has focused on the degree to which misconceptions may be based in the complexity of biological information or in pedagogical choices, rather than in deep-seated cognitive patterns. Cognitive psychology research has established that humans develop early intuitive assumptions to make sense of the world. In this study, we used a written assessment tool to investigate undergraduate students' misconceptions of antibiotic resistance, use of intuitive reasoning, and application of evolutionary knowledge to antibiotic resistance. We found a majority of students produced and agreed with misconceptions, and intuitive reasoning was present in nearly all students' written explanations. Acceptance of a misconception was significantly associated with production of a hypothesized form of intuitive thinking (all p ≤ 0.05). Intuitive reasoning may represent a subtle but innately appealing linguistic shorthand, and instructor awareness of intuitive reasoning's relation to student misunderstandings has potential for addressing persistent misconceptions. © 2017 M. Richard et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Changing the Antibiotic Prescribing of general practice registrars: the ChAP study protocol for a prospective controlled study of a multimodal educational intervention.

PubMed

van Driel, Mieke L; Morgan, Simon; Tapley, Amanda; McArthur, Lawrie; McElduff, Patrick; Yardley, Lucy; Dallas, Anthea; Deckx, Laura; Mulquiney, Katie; Davis, Joshua S; Davey, Andrew; Henderson, Kim; Little, Paul; Magin, Parker J

2016-06-06

Australian General Practitioners (GPs) are generous prescribers of antibiotics, prompting concerns including increasing antimicrobial resistance in the community. Recent data show that GPs in vocational training have prescribing patterns comparable with the high prescribing rate of their established GP supervisors. Evidence-based guidelines consistently advise that antibiotics are not indicated for uncomplicated upper respiratory tract infections (URTI) and are rarely indicated for acute bronchitis. A number of interventions have been trialled to promote rational antibiotic prescribing by established GPs (with variable effectiveness), but the impact of such interventions in a training setting is unclear. We hypothesise that intervening while early-career GPs are still developing their practice patterns and prescribing habits will result in better adherence to evidence-based guidelines as manifested by lower antibiotic prescribing rates for URTIs and acute bronchitis. The intervention consists of two online modules, a face-to-face workshop for GP trainees, a face-to-face workshop for their supervisors and encouragement for the trainee-supervisor dyad to include a case-based discussion of evidence-based antibiotic prescribing in their weekly one-on-one teaching meetings. We will use a non-randomised, non-equivalent control group design to assess the impact on antibiotic prescribing for acute upper respiratory infections and acute bronchitis by GP trainees in vocational training. Early-career GPs who are still developing their clinical practice and prescribing habits are an underutilized target-group for interventions to curb the growth of antimicrobial resistance in the community. Interventions that are embedded into existing training programs or are linked to continuing professional development have potential to increase the impact of existing interventions at limited additional cost. Australian New Zealand Clinical Trials Registry, ACTRN12614001209684 (registered 17/11/2014).

Antibiotic Resistance

MedlinePlus

... lives. But there is a growing problem of antibiotic resistance. It happens when bacteria change and become able ... resistant to several common antibiotics. To help prevent antibiotic resistance Don't use antibiotics for viruses like colds ...

Antibiotics and Resistance: Glossary

MedlinePlus

... R S T U V W X Y Z Antibacterials (see Antibacterial agents ) Antibiotics (see About bacteria and antibiotics ) Antibiotic ... antibiotic resistance? When and how to take antibiotics Antibacterial agents Bioterrorism & stockpiling antibiotics The Cost of Resistance ...

Epidemiological Interpretation of Studies Examining the Effect of Antibiotic Usage on Resistance

PubMed Central

Schechner, Vered; Temkin, Elizabeth; Harbarth, Stephan; Carmeli, Yehuda

2013-01-01

SUMMARY Bacterial resistance to antibiotics is a growing clinical problem and public health threat. Antibiotic use is a known risk factor for the emergence of antibiotic resistance, but demonstrating the causal link between antibiotic use and resistance is challenging. This review describes different study designs for assessing the association between antibiotic use and resistance and discusses strengths and limitations of each. Approaches to measuring antibiotic use and antibiotic resistance are presented. Important methodological issues such as confounding, establishing temporality, and control group selection are examined. PMID:23554418

A Mechanism of Unidirectional Transformation, Leading to Antibiotic Resistance, Occurs within Nasopharyngeal Pneumococcal Biofilm Consortia.

PubMed

Lattar, Santiago M; Wu, Xueqing; Brophy, Jennifer; Sakai, Fuminori; Klugman, Keith P; Vidal, Jorge E

2018-05-15

Streptococcus pneumoniae acquires genes for resistance to antibiotics such as streptomycin (Str) or trimethoprim (Tmp) by recombination via transformation of DNA released by other pneumococci and closely related species. Using naturally transformable pneumococci, including strain D39 serotype 2 (S2) and TIGR4 (S4), we studied whether pneumococcal nasopharyngeal transformation was symmetrical, asymmetrical, or unidirectional. Incubation of S2 Tet and S4 Str in a bioreactor simulating the human nasopharynx led to the generation of Spn Tet/Str recombinants. Double-resistant pneumococci emerged soon after 4 h postinoculation at a recombination frequency (rF) of 2.5 × 10 -4 while peaking after 8 h at a rF of 1.1 × 10 -3 Acquisition of antibiotic resistance genes by transformation was confirmed by treatment with DNase I. A high-throughput serotyping method demonstrated that all double-resistant pneumococci belonged to one serotype lineage (S2 Tet/Str ) and therefore that unidirectional transformation had occurred. Neither heterolysis nor availability of DNA for transformation was a factor for unidirectional transformation given that the density of each strain and extracellular DNA (eDNA) released from both strains were similar. Unidirectional transformation occurred regardless of the antibiotic-resistant gene carried by donors or acquired by recipients and regardless of whether competence-stimulating peptide-receptor cross talk was allowed. Moreover, unidirectional transformation occurred when two donor strains (e.g., S4 Str and S19F Tmp ) were incubated together, leading to S19F Str/Tmp but at a rF 3 orders of magnitude lower (4.9 × 10 -6 ). We finally demonstrated that the mechanism leading to unidirectional transformation was due to inhibition of transformation of the donor by the recipient. IMPORTANCE Pneumococcal transformation in the human nasopharynx may lead to the acquisition of antibiotic resistance genes or genes encoding new capsular variants. Antibiotics and vaccines are currently putting pressure on a number of strains, leading to an increase in antibiotic resistance and serotype replacement. These pneumococcal strains are also acquiring virulence traits from vaccine types via transformation. In this study, we recapitulated multiple-strain colonization with strains carrying a resistance marker and selected for those acquiring resistance to two or three antibiotics, such as would occur in the human nasopharynx. Strains acquiring dual and triple resistance originated from one progenitor, demonstrating that transformation was unidirectional. Unidirectional transformation was the result of inhibition of transformation of donor strains. Unidirectional transformation has implications for the understanding of acquisition patterns of resistance determinants or capsule-switching events. Copyright © 2018 Lattar et al.

Antibiotic resistance and molecular typing among cockle (Anadara granosa) strains of Vibrio parahaemolyticus by polymerase chain reaction (PCR)-based analysis.

PubMed

Sahilah, A M; Laila, R A S; Sallehuddin, H Mohd; Osman, H; Aminah, A; Ahmad Azuhairi, A

2014-02-01

Genomic DNA of Vibrio parahaemolyticus were characterized by antibiotic resistance, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) analysis. These isolates originated from 3 distantly locations of Selangor, Negeri Sembilan and Melaka (East coastal areas), Malaysia. A total of 44 (n = 44) of tentatively V. parahaemolyticus were also examined for the presence of toxR, tdh and trh gene. Of 44 isolates, 37 were positive towards toxR gene; while, none were positive to tdh and trh gene. Antibiotic resistance analysis showed the V. parahaemolyticus isolates were highly resistant to bacitracin (92%, 34/37) and penicillin (89%, 33/37) followed by resistance towards ampicillin (68%, 25/37), cefuroxime (38%, 14/37), amikacin (6%, 2/37) and ceftazidime (14%, 5/37). None of the V. parahaemolyticus isolates were resistant towards chloramphenicol, ciprofloxacin, ceftriaxone, enrofloxacin, norfloxacin, streptomycin and vancomycin. Antibiogram patterns exhibited, 9 patterns and phenotypically less heterogenous when compared to PCR-based techniques using ERIC- and RAPD-PCR. The results of the ERIC- and RAPD-PCR were analyzed using GelCompare software. ERIC-PCR with primers ERIC1R and ERIC2 discriminated the V. parahaemolyticus isolates into 6 clusters and 21 single isolates at a similarity level of 80%. While, RAPD-PCR with primer Gen8 discriminated the V. parahaemolyticus isolates into 11 clusters and 10 single isolates and Gen9 into 8 clusters and 16 single isolates at the same similarity level examined. Results in the presence study demonstrated combination of phenotypically and genotypically methods show a wide heterogeneity among cockle isolates of V. parahaemolyticus.

Interaction of Vaccination and Reduction of Antibiotic Use Drives Unexpected Increase of Pneumococcal Meningitis

PubMed Central

de Cellès, Matthieu Domenech; Pons-Salort, Margarita; Varon, Emmanuelle; Vibet, Marie-Anne; Ligier, Caroline; Letort, Véronique; Opatowski, Lulla; Guillemot, Didier

2015-01-01

Antibiotic-use policies may affect pneumococcal conjugate-vaccine effectiveness. The reported increase of pneumococcal meningitis from 2001 to 2009 in France, where a national campaign to reduce antibiotic use was implemented in parallel to the introduction of the 7-valent conjugate vaccine, provides unique data to assess these effects. We constructed a mechanistic pneumococcal transmission model and used likelihood to assess the ability of competing hypotheses to explain that increase. We find that a model integrating a fitness cost of penicillin resistance successfully explains the overall and age-stratified pattern of serotype replacement. By simulating counterfactual scenarios of public health interventions in France, we propose that this fitness cost caused a gradual and pernicious interaction between the two interventions by increasing the spread of nonvaccine, penicillin-susceptible strains. More generally, our results indicate that reductions of antibiotic use may counteract the benefits of conjugate vaccines introduced into countries with low vaccine-serotype coverages and high-resistance frequencies. Our findings highlight the key role of antibiotic use in vaccine-induced serotype replacement and suggest the need for more integrated approaches to control pneumococcal infections. PMID:26063589

Interaction of Vaccination and Reduction of Antibiotic Use Drives Unexpected Increase of Pneumococcal Meningitis.

PubMed

de Cellès, Matthieu Domenech; Pons-Salort, Margarita; Varon, Emmanuelle; Vibet, Marie-Anne; Ligier, Caroline; Letort, Véronique; Opatowski, Lulla; Guillemot, Didier

2015-06-11

Antibiotic-use policies may affect pneumococcal conjugate-vaccine effectiveness. The reported increase of pneumococcal meningitis from 2001 to 2009 in France, where a national campaign to reduce antibiotic use was implemented in parallel to the introduction of the 7-valent conjugate vaccine, provides unique data to assess these effects. We constructed a mechanistic pneumococcal transmission model and used likelihood to assess the ability of competing hypotheses to explain that increase. We find that a model integrating a fitness cost of penicillin resistance successfully explains the overall and age-stratified pattern of serotype replacement. By simulating counterfactual scenarios of public health interventions in France, we propose that this fitness cost caused a gradual and pernicious interaction between the two interventions by increasing the spread of nonvaccine, penicillin-susceptible strains. More generally, our results indicate that reductions of antibiotic use may counteract the benefits of conjugate vaccines introduced into countries with low vaccine-serotype coverages and high-resistance frequencies. Our findings highlight the key role of antibiotic use in vaccine-induced serotype replacement and suggest the need for more integrated approaches to control pneumococcal infections.

Characterization of antibiotic resistance genes in representative organic solid wastes: Food waste-recycling wastewater, manure, and sewage sludge.

PubMed

Lee, Jangwoo; Shin, Seung Gu; Jang, Hyun Min; Kim, Young Beom; Lee, Joonyeob; Kim, Young Mo

2017-02-01

In this research, the distribution of antibiotic resistance genes (ARGs) was characterized in representative organic solid waste (OSW) in Korea: food waste-recycling wastewater (FRW), manure, and sewage sludge. The amounts of total ARG (gene copies/16S rRNA gene copies) was greatest in manure followed by sewage sludge and FRW. Interestingly, there were significantly different patterns in the diversity and mechanisms of ARGs. For example, a significant proportion of ARGs were tetracycline resistant genes in all the OSW (40.4-78.2%). β-lactam antibiotics resistant genes were higher in the FRW samples than in other types of OSW but sulfonamides resistant genes represented the greatest proportion in sludge. Regarding the characteristics of antibiotic resistance mechanisms, there was a relatively higher proportion of the ribosomal protection mechanism to tetracycline observed in the FRW and manure samples. However, tetracycline resistant genes with direct interaction were relatively higher in the sewage sludge samples. sul1 was the dominant subtype in all the OSW types and detection of ermB was observed although there was no ermC detected in sewage sludge. There were significant correlations between the occurrences of ARG subtypes: tetB and tetG in all OSW (P<0.01); tetE and tetQ only in sludge (P<0.01). The Class 1 integron-integrase gene (intI1) was significantly correlated with total ARGs only in manure and sludge (P<0.05), revealing potential horizontal gene transfer in these OSW. Copyright © 2016 Elsevier B.V. All rights reserved.

Epidemiology and characteristics of urinary tract infections in children and adolescents.

PubMed

Hanna-Wakim, Rima H; Ghanem, Soha T; El Helou, Mona W; Khafaja, Sarah A; Shaker, Rouba A; Hassan, Sara A; Saad, Randa K; Hedari, Carine P; Khinkarly, Rima W; Hajar, Farah M; Bakhash, Marwan; El Karah, Dima; Akel, Imad S; Rajab, Mariam A; Khoury, Mireille; Dbaibo, Ghassan S

2015-01-01

Urinary tract infections (UTIs) are among the most common infections in the pediatric population. Over the last two decades, antibiotic resistance is increasing significantly as extended spectrum beta lactamase (ESBL) producing organisms are emerging. The aim of this study is to provide a comprehensive view of the epidemiologic characteristics of UTIs in hospitalized children, examine the risk factors of UTIs caused by ESBL-producing organisms, and determine the resistance patterns in the isolated organisms over the last 10 years. Retrospective chart review was conducted at two Lebanese medical centers. Subjects were identified by looking at the following ICD-9 discharge codes: "Urinary tract infection," "UTI," "Cystitis," and/or "Pyelonephritis." Children less than 18 years of age admitted for UTI between January 1st, 2001 and December 31st, 2011 were included. Cases whose urine culture result did not meet our definition for UTI were excluded. Chi-square, Fisher's exact test, and multivariate logistic regression were used to determine risk factors for ESBL. Linear regression analysis was used to determine resistance patterns. The study included 675 cases with a median age of 16 months and female predominance of 77.7% (525 cases). Of the 584 cases caused by Escherichia coli or Klebsiella spp, 91 cases (15.5%) were found to be ESBL-producing organisms. Vesico-ureteral reflux and previous antibiotics use were found to be independent risk factors for ESBL-producing E. coli and Klebsiella spp. (p < 0.05). A significant linear increase in resistance to all generations of Cephalosporins (r (2) = 0.442) and Fluoroquinolones (r (2) = 0.698) was found. The recognition of risk factors for infection with ESBL-producing organisms and the observation of increasing overall resistance to antibiotics warrant further studies that might probably lead to new recommendations to guide management of UTIs and antibiotic use in children and adolescents.

Effects of in-feed egg yolk antibodies on Salmonella shedding, bacterial antibiotic resistance, and health of pigs.

PubMed

Mathew, Alan G; Rattanatabtimtong, Sukanya; Nyachoti, Charles M; Fang, Lin

2009-02-01

To determine effects of anti-Salmonella egg yolk antibodies on shedding and antibiotic resistance of Salmonella enterica Typhimurium, newly weaned pigs were randomly assigned to six dietary treatments. These treatment groups were (i) a control (basal) diet without additives and similar diets with (ii) egg yolk powder derived from chickens challenged with Salmonella Typhimurium antigens, (iii) a commercial egg yolk powder control, (iv) apramycin for 14 days followed by carbadox, (v) oxytetracycline, or (vi) spray-dried plasma protein. Treatments were provided beginning on day 3 of the trial, and all pigs were challenged with 5 ml of 10(8) CFU/ml Salmonella Typhimurium on day 7. Fecal samples were collected on days 0, 7, 8, 12, 14, 21, 58, 88, and 118 for isolation of Salmonella and Escherichia coli to determine shedding and antibiotic resistance patterns. Body weights, white blood cell counts, and plasma concentrations of anti-Salmonella immunoglobulin G and porcine interleukin 1beta were analyzed as indicators of animal health. The percentage of pigs shedding Salmonella was lower for antibiotic treatment groups compared with other groups; however, resistance was greater in E. coli from pigs fed antibiotics than in pigs in other treatment groups. Health and performance indicators (pig weight gains, white blood cell counts, and plasma concentrations of anti-Salmonella antibodies) did not differ between treatment groups. These studies indicate that feeding egg yolk containing anti-Salmonella immunoglobulin Y may not be effective in controlling shedding of Salmonella in pigs.

Meropenem use and colonization by antibiotic-resistant Gram-negative bacilli in a pediatric intensive care unit.

PubMed

Toltzis, Philip; Dul, Michael; O'Riordan, Mary Ann; Melnick, David; Lo, Mathew; Blumer, Jeffrey

2009-01-01

The carbapenems are broad-spectrum beta-lactam antibiotics with activity against most organisms encountered in the pediatric intensive care unit (PICU). In anticipation of their increased use in critically ill children, we measured the effect of sustained meropenem use on the pattern of Gram-negative bacillus colonization in patients admitted to a tertiary care PICU. : Prospective preintervention/postintervention comparison. Medical/surgical PICU. Consecutive PICU admissions over 2.5 yrs. After a 6-mo baseline period, all children with serious infections admitted to the PICU during the subsequent 2 yrs were administered meropenem. The incidence of colonization by Gram-negative bacilli resistant to one of a battery of broad-spectrum parenteral agents, and by organisms resistant specifically to meropenem, during the baseline period was compared with the period of preferred meropenem use. During the period of preferred meropenem use, the amount of meropenem used increased >seven-fold, whereas the use of other advanced generation beta-lactams was reduced by nearly 80%. The mean prevalence of colonization by antibiotic-resistant bacilli in general was not statistically altered during the period of meropenem preference (7.3 organisms/100 patient-days, vs. 9.4 organisms/100 patient-days at baseline, p < 0.09). The prevalence of colonization by Gram-negative organisms resistant specifically to meropenem was 0.61 organisms/100 patient-days during the baseline period vs. 1.04 organisms/100 patient-days during the period of meropenem preference (p < 0.30). The incidence of nosocomial infections did not change, and the prevalence of nosocomial infections caused by meropenem-resistant organisms was always <1% of all admissions during the period of meropenem preference. There was no statistically detectable effect on the prevalence of colonization by Gram-negative organisms resistant to one or more classes of broad-spectrum parenteral antibiotics, or to colonization by organisms resistant specifically to meropenem, when meropenem was the preferred antibiotic in a PICU.

Antibiotic management of complicated intra-abdominal infections in adults: The Asian perspective

PubMed Central

Kurup, Asok; Liau, Kui-Hin; Ren, Jianan; Lu, Min-Chi; Navarro, Narciso S.; Farooka, Muhammad Waris; Usman, Nurhayat; Destura, Raul V.; Sirichindakul, Boonchoo; Tantawichien, Terapong; Lee, Christopher K.C.; Solomkin, Joseph S.

2014-01-01

Regional epidemiological data and resistance profiles are essential for selecting appropriate antibiotic therapy for intra-abdominal infections (IAIs). However, such information may not be readily available in many areas of Asia and current international guidelines on antibiotic therapy for IAIs are for Western countries, with the most recent guidance for the Asian region dating from 2007. Therefore, the Asian Consensus Taskforce on Complicated Intra-Abdominal Infections (ACT-cIAI) was convened to develop updated recommendations for antibiotic management of complicated IAIs (cIAIs) in Asia. This review article is based on a thorough literature review of Asian and international publications related to clinical management, epidemiology, microbiology, and bacterial resistance patterns in cIAIs, combined with the expert consensus of the Taskforce members. The microbiological profiles of IAIs in the Asian region are outlined and compared with Western data, and the latest available data on antimicrobial resistance in key pathogens causing IAIs in Asia is presented. From this information, antimicrobial therapies suitable for treating cIAIs in patients in Asian settings are proposed in the hope that guidance relevant to Asian practices will prove beneficial to local physicians managing IAIs. PMID:25568794

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

PubMed

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

2018-05-19

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

Monitoring roadside ditches for antibiotic resistant E. coli in forest and agricultural landscapes

NASA Astrophysics Data System (ADS)

Storrer, S.; Archibald, J. A.

2009-12-01

There is growing concern over the threat of antibiotic resistant bacteria and how they travel through natural environments. This study was developed to: (1) measure the quantities of antibiotic resistant Escherichia coli present in stormwater collected from roadside ditches, (2) examine the spatial and temporal distribution of antibiotic resistance and (3) explore the difference in antibiotic resistance between different land uses. Autosamplers were used to collect composite samples of stormwater flowing in roadside ditches located near manure fertilized fields or forested areas. Samples were filtered using standard membrane filtration methods and grown with and without antibiotics on EC medium containing MUG. Three antibiotics commonly used to treat infection in humans and dairy cows were used to measure antibiotic resistance: penicillin, ampicillin and tetracycline. Though antibiotic resistance was found at forested and farm sites, preliminary data suggest higher counts of antibiotic resistant E. coli near agricultural areas.

Quantitative proteomic view associated with resistance to clinically important antibiotics in Gram-positive bacteria: a systematic review

PubMed Central

Lee, Chang-Ro; Lee, Jung Hun; Park, Kwang Seung; Jeong, Byeong Chul; Lee, Sang Hee

2015-01-01

The increase of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) poses a worldwide and serious health threat. Although new antibiotics, such as daptomycin and linezolid, have been developed for the treatment of infections of Gram-positive pathogens, the emergence of daptomycin-resistant and linezolid-resistant strains during therapy has now increased clinical treatment failures. In the past few years, studies using quantitative proteomic methods have provided a considerable progress in understanding antibiotic resistance mechanisms. In this review, to understand the resistance mechanisms to four clinically important antibiotics (methicillin, vancomycin, linezolid, and daptomycin) used in the treatment of Gram-positive pathogens, we summarize recent advances in studies on resistance mechanisms using quantitative proteomic methods, and also examine proteins playing an important role in the bacterial mechanisms of resistance to the four antibiotics. Proteomic researches can identify proteins whose expression levels are changed in the resistance mechanism to only one antibiotic, such as LiaH in daptomycin resistance and PrsA in vancomycin resistance, and many proteins simultaneously involved in resistance mechanisms to various antibiotics. Most of resistance-related proteins, which are simultaneously associated with resistance mechanisms to several antibiotics, play important roles in regulating bacterial envelope biogenesis, or compensating for the fitness cost of antibiotic resistance. Therefore, proteomic data confirm that antibiotic resistance requires the fitness cost and the bacterial envelope is an important factor in antibiotic resistance. PMID:26322035

Plasmid profiles and antibiotic susceptibility patterns of Staphylococcus aureus isolates from Nigeria.

PubMed

Olukoya, D K; Asielue, J O; Olasupo, N A; Ikea, J K

1995-06-01

In an investigation into the problems of infections due to Staphylococcus aureus in Nigeria, 100 strains were isolated from various hospitals in Lagos. The strains were screened for the presence of plasmids and for susceptibility to antimicrobial agents. Plasmids were extracted by modification of the method of Takahashi and Nagono[1]. The plasmids were diverse in nature. The strains were found to be highly resistant to commonly prescribed antibiotics.

Bovine salmonellosis in Northeast of Iran: Frequency, genetic fingerprinting and antimicrobial resistance patterns of Salmonella spp.

PubMed Central

Halimi, Hessam A.; Seifi, Hesam A.; Rad, Mehrnaz

2014-01-01

Objective To evaluate serovar and antimicrobial resistance patterns of Salmonella spp isolated from healthy, diseased and necropsied cows and calves in this observational study. Methods Nineteen isolates recovered from feces and tissues of salmonellosis-affected animals of two commercial farms in north-east of Iran. In second part of the study, the two farms were sampled 4 times with an interval of 2 month. The samples included calves' feces, adult cows' feces, feeds, water, milk filters, and milk fed to calves. Five Salmonella were isolated from 332 fecal samples collected from calves and peri-parturient cows. No Salmonella was recovered from water, feed, milk filers and milk fed to calves. Results Salmonella Typhimurium was the most frequently isolate among all sero-groups. S. Dublin was only accounted for 8% (two out of 24) of isolates. Isolated Salmonella strains were used for the ERIC PCR DNA fingerprinting assay. Our results grouped Salmonella isolates into 3 clusters, suggesting that specific genotypes were responsible for each sero-group of Salmonella. The results also revealed diversity among Salmonella isolates in cluster III (sero-group B). Eighteen out of 19 Salmonella spp. were resistant to oxytetracycline. Five isolates out of 19 showed more than one drug resistance. Multi-drug resistance was seen only among Salmonella Typhimurium isolates. Enrofloxacin was the most susceptible antibiotic against all isolates in this study. Conclusion The emergence of multiple antibiotic-resistant strains of Salmonella Typhimurium should be of great concern to the public. No correlation between ERIC fingerprinting and resistance patterns of Salmonella isolates was found, which indicates resistance to antimicrobial agents was not related to specific genetic background. PMID:24144122

Bovine salmonellosis in northeast of Iran: frequency, genetic fingerprinting and antimicrobial resistance patterns of Salmonella spp.

PubMed

Halimi, Hessam A; Seifi, Hesam A; Rad, Mehrnaz

2014-01-01

To evaluate serovar and antimicrobial resistance patterns of Salmonella spp isolated from healthy, diseased and necropsied cows and calves in this observational study. Nineteen isolates recovered from feces and tissues of salmonellosis-affected animals of two commercial farms in north-east of Iran. In second part of the study, the two farms were sampled 4 times with an interval of 2 month. The samples included calves' feces, adult cows' feces, feeds, water, milk filters, and milk fed to calves. Five Salmonella were isolated from 332 fecal samples collected from calves and peri-parturient cows. No Salmonella was recovered from water, feed, milk filers and milk fed to calves. Salmonella Typhimurium was the most frequently isolate among all sero-groups. S. Dublin was only accounted for 8% (two out of 24) of isolates. Isolated Salmonella strains were used for the ERIC PCR DNA fingerprinting assay. Our results grouped Salmonella isolates into 3 clusters, suggesting that specific genotypes were responsible for each sero-group of Salmonella. The results also revealed diversity among Salmonella isolates in cluster III (sero-group B). Eighteen out of 19 Salmonella spp. were resistant to oxytetracycline. Five isolates out of 19 showed more than one drug resistance. Multi-drug resistance was seen only among Salmonella Typhimurium isolates. Enrofloxacin was the most susceptible antibiotic against all isolates in this study. The emergence of multiple antibiotic-resistant strains of Salmonella Typhimurium should be of great concern to the public. No correlation between ERIC fingerprinting and resistance patterns of Salmonella isolates was found, which indicates resistance to antimicrobial agents was not related to specific genetic background. Copyright © 2014 Asian Pacific Tropical Biomedical Magazine. Published by Elsevier B.V. All rights reserved.

Improved annotation of antibiotic resistance determinants reveals microbial resistomes cluster by ecology.

PubMed

Gibson, Molly K; Forsberg, Kevin J; Dantas, Gautam

2015-01-01

Antibiotic resistance is a dire clinical problem with important ecological dimensions. While antibiotic resistance in human pathogens continues to rise at alarming rates, the impact of environmental resistance on human health is still unclear. To investigate the relationship between human-associated and environmental resistomes, we analyzed functional metagenomic selections for resistance against 18 clinically relevant antibiotics from soil and human gut microbiota as well as a set of multidrug-resistant cultured soil isolates. These analyses were enabled by Resfams, a new curated database of protein families and associated highly precise and accurate profile hidden Markov models, confirmed for antibiotic resistance function and organized by ontology. We demonstrate that the antibiotic resistance functions that give rise to the resistance profiles observed in environmental and human-associated microbial communities significantly differ between ecologies. Antibiotic resistance functions that most discriminate between ecologies provide resistance to β-lactams and tetracyclines, two of the most widely used classes of antibiotics in the clinic and agriculture. We also analyzed the antibiotic resistance gene composition of over 6000 sequenced microbial genomes, revealing significant enrichment of resistance functions by both ecology and phylogeny. Together, our results indicate that environmental and human-associated microbial communities harbor distinct resistance genes, suggesting that antibiotic resistance functions are largely constrained by ecology.

Resistance diagnosis and the changing epidemiology of antibiotic resistance.

PubMed

McAdams, David

2017-01-01

Widespread adoption of point-of-care resistance diagnostics (POCRD) reduces ineffective antibiotic use but could increase overall antibiotic use. Indeed, in the context of a standard susceptible-infected epidemiological model with a single antibiotic, POCRD accelerates the rise of resistance in the disease-causing bacterial population. When multiple antibiotics are available, however, POCRD may slow the rise of resistance even as more patients receive antibiotic treatment, belying the conventional wisdom that antibiotics are "exhaustible resources" whose increased use necessarily promotes the rise of resistance. © 2017 New York Academy of Sciences.

The multifaceted roles of antibiotics and antibiotic resistance in nature

PubMed Central

Sengupta, Saswati; Chattopadhyay, Madhab K.; Grossart, Hans-Peter

2013-01-01

Antibiotics are chemotherapeutic agents, which have been a very powerful tool in the clinical management of bacterial diseases since the 1940s. However, benefits offered by these magic bullets have been substantially lost in subsequent days following the widespread emergence and dissemination of antibiotic-resistant strains. While it is obvious that excessive and imprudent use of antibiotics significantly contributes to the emergence of resistant strains, antibiotic resistance is also observed in natural bacteria of remote places unlikely to be impacted by human intervention. Both antibiotic biosynthetic genes and resistance-conferring genes have been known to evolve billions of years ago, long before clinical use of antibiotics. Hence it appears that antibiotics and antibiotics resistance determinants have some other roles in nature, which often elude our attention because of overemphasis on the therapeutic importance of antibiotics and the crisis imposed by the antibiotic resistance in pathogens. In the natural milieu, antibiotics are often found to be present in sub-inhibitory concentrations acting as signaling molecules supporting the process of quorum sensing and biofilm formation. They also play an important role in the production of virulence factors and influence host–parasite interactions (e.g., phagocytosis, adherence to the target cell, and so on). The evolutionary and ecological aspects of antibiotics and antibiotic resistance in the naturally occurring microbial community are little understood. Therefore, the actual role of antibiotics in nature warrants in-depth investigations. Studies on such an intriguing behavior of the microorganisms promise insight into the intricacies of the microbial physiology and are likely to provide some lead in controlling the emergence and subsequent dissemination of antibiotic resistance. This article highlights some of the recent findings on the role of antibiotics and the genes that confer resistance to antibiotics in nature. PMID:23487476

Next-generation approaches to understand and combat the antibiotic resistome.

PubMed

Crofts, Terence S; Gasparrini, Andrew J; Dantas, Gautam

2017-07-01

Antibiotic resistance is a natural feature of diverse microbial ecosystems. Although recent studies of the antibiotic resistome have highlighted barriers to the horizontal transfer of antibiotic resistance genes between habitats, the rapid global spread of genes that confer resistance to carbapenem, colistin and quinolone antibiotics illustrates the dire clinical and societal consequences of such events. Over time, the study of antibiotic resistance has grown from focusing on single pathogenic organisms in axenic culture to studying antibiotic resistance in pathogenic, commensal and environmental bacteria at the level of microbial communities. As the study of antibiotic resistance advances, it is important to incorporate this comprehensive approach to better inform global antibiotic resistance surveillance and antibiotic development. It is increasingly becoming apparent that although not all resistance genes are likely to geographically and phylogenetically disseminate, the threat presented by those that are is serious and warrants an interdisciplinary research focus. In this Review, we highlight seminal work in the resistome field, discuss recent advances in the studies of resistomes, and propose a resistome paradigm that can pave the way for the improved proactive identification and mitigation of emerging antibiotic resistance threats.

Study protocol for One Health data collections, analyses and intervention of the Sino-Swedish integrated multisectoral partnership for antibiotic resistance containment (IMPACT)

PubMed Central

Sun, Qiang; Wang, Yang; Hulth, Anette; Xiao, Yonghong; Nilsson, Lennart E; Li, Xuewen; Bi, Zhenwang; Liu, Yuqing; Yin, Hong; Luo, Yanbo; Nilsson, Maud; Sun, Chengtao; Zhu, Yiqing; Zheng, Beiwen; Chen, Baoli; Sun, Pan; Ding, Lilu; Xia, Xi; Ottoson, Jakob; Löfmark, Sonja; Dyar, Oliver James; Börjesson, Stefan; Lundborg, Cecilia Stalsby

2018-01-01

Introduction To effectively minimise the emergence and dissemination of antibiotic resistant bacteria, a holistic One Health approach is called for. The Sino-Swedish Integrated Multisectoral Partnership for Antibiotic Resistance Containment is a cross-sectoral and integrated project on antibiotic resistance, conducted in Shandong Province in China. This paper outlines the overall study protocol for the project. To our knowledge, this is the first research programme aiming to take a true holistic approach across multiple sectors simultaneously in China, and the first to incorporate both antibiotic use and infection prevention and control in addition to antibiotic resistance patterns. The project aims to address gaps in current knowledge and seeks to improve the situation through a system-wide intervention. By using a One Health approach we can address important research questions that individual discipline investigations are unable to. The results obtained should thus more closely reflect the world in which human health, animal health and the environment are inextricably and intimately interlinked. Methods and analysis Both quantitative and qualitative studies are included for households from 12 villages, their surrounding environment and a tertiary care hospital in a nearby town. The studies include analyses of antibiotic consumption for humans and pigs; qualitative and quantitative data on perceptions, knowledge and attitudes; faecal carriage of extended spectrum β-lactamase and carbapenemase-producing Enterobacteriaceae from pigs and humans, and occurrence in household drinking water, surface water, waste water and clinical bacterial isolates from the hospital. Carriage of methicillin-resistant Staphylococcus aureus in humans, household pigs and clinical bacterial isolates is also investigated. Furthermore, potential inter-relationships between these sources are analysed. A multifaceted One Health intervention is designed and implemented in 6 of the 12 villages. Repeated and continuous data collections take place over 2 years, where the repeated data collection is performed after 1 year of intervention. Comparisons are made between intervention and control villages, before and after the intervention. Ethics Ethics approval was obtained from the first Affiliated Hospital, College of Medicine, Zhejiang University, China, reference number 2015#185 and 2015#283. PMID:29358424

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

PubMed

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

2017-09-26

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

A Survey and Analysis of the American Public's Perceptions and Knowledge About Antibiotic Resistance

PubMed Central

Carter, Rebecca R.; Sun, Jiayang; Jump, Robin L. P.

2016-01-01

Background. Little is known about the American public's perceptions or knowledge about antibiotic-resistant bacteria or antibiotic misuse. We hypothesized that although many people recognize antibiotic resistance as a problem, they may not understand the relationship between antibiotic consumption and selection of resistant bacteria. Methods. We developed and tested a survey asking respondents about their perceptions and knowledge regarding appropriate antibiotic use. Respondents were recruited with the Amazon Mechanical Turk crowdsourcing platform. The survey, carefully designed to assess a crowd-sourced population, asked respondents to explain “antibiotic resistance” in their own words. Subsequent questions were multiple choice. Results. Of 215 respondents, the vast majority agreed that inappropriate antibiotic use contributes to antibiotic resistance (92%), whereas a notable proportion (70%) responded neutrally or disagreed with the statement that antibiotic resistance is a problem. Over 40% of respondents indicated that antibiotics were the best choice to treat a fever or a runny nose and sore throat. Major themes from the free-text responses included that antibiotic resistance develops by bacteria, or by the infection, or the body (ie, an immune response). Minor themes included antibiotic overuse and antibiotic resistance caused by bacterial adaptation or an immune response. Conclusions. Our findings indicate that the public is aware that antibiotic misuse contributes to antibiotic resistance, but many do not consider it to be an important problem. The free-text responses suggest specific educational targets, including the difference between an immune response and bacterial adaptation, to increase awareness and understanding of antibiotic resistance. PMID:27382598

Effect of aminglycoside administration on the occurrence and multiplication of resistant bacteria.

PubMed

Milas, Josip; Kalenić, Smilja; Milas, Vesna; Miskulin, Maja; Vuković, Dubravka; Rudan, Stjepan; Puntarić, Dinko

2009-06-01

In the prospective study the susceptibility of 41 Escherichia coli strains and 55 Pseudomonas aeruginosa strains to gentamicin, netilmicin and amikacin was tested at a 2-year interval (period I April 1998 to March 1999, and period II April to July 2001). Genotyping was performed by pulsed-field gel electrophoresis, and a clone based on 80% or 90% similarity was determined for each of the study bacteria. In 24 (32.0%) clones, strains showed no variation over 2-year interval, supporting the hypothesis on a priori susceptible strains. Transformation from susceptibility in period I to resistance in period II was demonstrated in 5 (6.7%) clones, a pattern consistent with the concept of bacterial development of resistance under the influence of antibiotics. However, there were 10 (13.3%) clones whose strains exhibited an inverse pattern. Accordingly, two-way transformation of susceptibility took place during the study period. The utilization of the study aminoglycosides had no major impact on the variation of microbial susceptibility. Changes in microbial susceptibility were found to follow some regular patterns, which were not influenced by the study aminoglycosides. Two phenomena were observed: (i) there were stable clones that did not develop resistance in spite of selective antibiotic challenge; and (ii) changes of susceptibility in isolated bacteria from both inpatient and outpatient strains of the same clone were two-way and reversible.

Emergence and dissemination of antibiotic resistance: a global problem.

PubMed

Choudhury, R; Panda, S; Singh, D V

2012-01-01

Antibiotic resistance is a major problem in clinical health settings. Interestingly the origin of many of antibiotic resistance mechanisms can be traced back to non-pathogenic environmental organisms. Important factors leading to the emergence and spread of antibiotic resistance include absence of regulation in the use of antibiotics, improper waste disposal and associated transmission of antibiotic resistance genes in the community through commensals. In this review, we discussed the impact of globalisation on the transmission of antibiotic resistance genes in bacteria through immigration and export/import of foodstuff. The significance of surveillance to define appropriate use of antibiotics in the clinic has been included as an important preventive measure.

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

PubMed

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

2018-06-01

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

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

PubMed

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

2015-06-01

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

Impact of anthropogenic activities on the dissemination of antibiotic resistance across ecological boundaries.

PubMed

Tripathi, Vijay; Cytryn, Eddie

2017-02-28

Antibiotics are considered to be one of the major medical breakthroughs in history. Nonetheless, over the past four decades, antibiotic resistance has reached alarming levels worldwide and this trend is expected to continue to increase, leading some experts to forecast the coming of a 'post-antibiotic' era. Although antibiotic resistance in pathogens is traditionally linked to clinical environments, there is a rising concern that the global propagation of antibiotic resistance is also associated with environmental reservoirs that are linked to anthropogenic activities such as animal husbandry, agronomic practices and wastewater treatment. It is hypothesized that the emergence and dissemination of antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) within and between environmental microbial communities can ultimately contribute to the acquisition of antibiotic resistance in human pathogens. Nonetheless, the scope of this phenomenon is not clear due to the complexity of microbial communities in the environment and methodological constraints that limit comprehensive in situ evaluation of microbial genomes. This review summarizes the current state of knowledge regarding antibiotic resistance in non-clinical environments, specifically focusing on the dissemination of antibiotic resistance across ecological boundaries and the contribution of this phenomenon to global antibiotic resistance. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Etiology and Antimicrobial Susceptibility Pattern of Pathogenic Bacteria in Children Subjected to UTI: A Referral Hospital-Based Study in Northwest of Iran.

PubMed

Rezaee, Mohammad Ahangarzadeh; Abdinia, Babak

2015-09-01

Urinary tract infection (UTI) is 1 of the most common bacterial diseases in children with a considerable resistance to antimicrobials. This 5 years prospective study was carried out to determine the frequency of isolation and antimicrobial resistance patterns of uropathogens among children subjected to urine culture at Tabriz Children Educational-Health Care Center, in the northwest of Iran. Organisms were isolated using standard culture techniques. Frequency of UTI among children examined by urine culture was 3.6%. The isolated bacteria were Escherichia coli (71.4%), followed by Klebsiella spp. (9.6%), Enterococcus spp. (6.4%), Pseudomonas aeruginosa (4.2%), Serratia spp. (4.2%), and Enterobacter spp. (4.2%). E coli resistance levels were 11% for nitrofurantoin, 15% for ciprofloxacin, 25% for nalidixic acid, and 30% to 75% for amikacin, gentamicin, ceftriaxone, ceftizoxime, cefotaxime, and co-trimoxazole. Among the tested antibiotics, ciprofloxacin, showed the highest activity (100%) against Klebsiella and P aeruginosa isolates followed by amikacin, nalidixic acid, and gentamicin. Overall, the highly active antibiotic against Gram-negative and Gram-positive organisms was amikacin and then ciprofloxacin. On the other hand, the empirical initial therapy with co-trimoxazole and third-generation cephalosporins would be inadequate for more cases of UTI in the study area. Moreover, susceptibility testing should be carried out on all clinical isolates, and the empirical antibiotic treatment changed accordingly.

Pathogen and antimicrobial resistance profiles of culture-proven neonatal sepsis in Southwest China, 1990-2014.

PubMed

Lu, Qi; Zhou, Min; Tu, Yan; Yao, Yao; Yu, Jialin; Cheng, Shupeng

2016-10-01

Neonatal sepsis (NS) sustains high mortality and morbidity in China, but data on the epidemiology and antimicrobial resistance patterns of NS pathogens are limited. The clinical features, aetiology and antimicrobial resistance of culture-proven NS were analysed over a period of 25 years in the metropolitan city of Chongqing in Southwest China. The occurrence rates of neonatal early-onset sepsis (EOS) were found to gradually decrease while late-onset sepsis (LOS) was kept stable from 1990 to 2014. Although coagulase-negative staphylococcus (CoNS) sepsis accounted for most infections, the occurrence rates of CoNS sepsis gradually decreased, especially in EOS. Escherichia coli and Klebsiella were common Gram-negative bacteria. The occurrence rates of E. coli and Klebsiella remained stable in EOS; however, in LOS, those had increased mildly, especially from 2009 to 2014. Although a high-degree resistance to common first- and second-line antimicrobials was observed for the main causative pathogens of NS, the gentamicin-resistance rate declined gradually from the year 2003. Similarly, the ceftazidime-resistance rate of E. coli dropped gradually from the year 2007. The alarmingly high degree of antibiotic resistance calls for urgent evaluation and development of antibiotic policy and protocols for the treatment of NS. Clinicians should strictly control the antibiotics use, decrease invasive manipulations and shorten hospitalisation to prevent LOS. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

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

PubMed Central

Yosef, Ido; Manor, Miriam; Kiro, Ruth

2015-01-01

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

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

PubMed

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

2015-06-09

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

Antibiotic resistance and molecular analysis of Staphylococcus aureus isolated from cow's milk and dairy products in northeast Brazil.

PubMed

Silveira-Filho, Vladimir M; Luz, Isabelle S; Campos, Ana Paula F; Silva, Wellington M; Barros, Maria Paloma S; Medeiros, Elizabeth S; Freitas, Manuela F L; Mota, Rinaldo A; Sena, Maria J; Leal-Balbino, Tereza C

2014-04-01

This work aimed to assess the clonal distribution among 94 strains of Staphylococcus aureus isolated from cow's milk, raw cheese, and a milking machine in 12 dairy farms in northeast Brazil, by analyzing different typing methods and detecting resistance and toxigenic profiles. For the first time, isolates of this region were assessed simultaneously by the polymorphism of the 3'-end coa gene and 16S-23S rDNA, pulsed-field gel electrophoresis, antibiotic resistance phenotyping, and toxigenic arsenal. Although pulsed-field gel electrophoresis patterns showed a wider variation (discriminatory index 0.83) than the PCR-based methods, the internal transcribed spacer-PCR proved to be a useful and inexpensive procedure for conducting epidemiological surveys of S. aureus on a regional scale. Each dairy farm had its own resistance profile, and in two herds, 63% of the strains were multiresistant, probably due to the indiscriminate use of antibiotics in bovine mastitis treatment. No methicillin-resistant S. aureus strains were detected in this study; however, 93.6% of S. aureus strains harbored variable profiles of staphylococcal enterotoxin genes seg, seh, sei, and sej. Transcriptional analysis revealed that 53.3% of staphylococcal enterotoxin genes actually transcribed, pointing out the food poisoning risk of these dairy products to consumers in the region. Based on the detection of the most prevalent clones in a herd or region, appropriate antibiotic therapy and specific immunization can be used for the treatment and control of staphylococcal mastitis.

Antibiotic resistance increases with local temperature

NASA Astrophysics Data System (ADS)

MacFadden, Derek R.; McGough, Sarah F.; Fisman, David; Santillana, Mauricio; Brownstein, John S.

2018-06-01

Bacteria that cause infections in humans can develop or acquire resistance to antibiotics commonly used against them1,2. Antimicrobial resistance (in bacteria and other microbes) causes significant morbidity worldwide, and some estimates indicate the attributable mortality could reach up to 10 million by 20502-4. Antibiotic resistance in bacteria is believed to develop largely under the selective pressure of antibiotic use; however, other factors may contribute to population level increases in antibiotic resistance1,2. We explored the role of climate (temperature) and additional factors on the distribution of antibiotic resistance across the United States, and here we show that increasing local temperature as well as population density are associated with increasing antibiotic resistance (percent resistant) in common pathogens. We found that an increase in temperature of 10 °C across regions was associated with an increases in antibiotic resistance of 4.2%, 2.2%, and 2.7% for the common pathogens Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus. The associations between temperature and antibiotic resistance in this ecological study are consistent across most classes of antibiotics and pathogens and may be strengthening over time. These findings suggest that current forecasts of the burden of antibiotic resistance could be significant underestimates in the face of a growing population and climate change4.

Presence of antibiotic resistance genes in a sewage treatment plant in Thibodaux, Louisiana, USA.

PubMed

Naquin, Anthony; Shrestha, Arsen; Sherpa, Mingma; Nathaniel, Rajkumar; Boopathy, Raj

2015-01-01

Increasing uses and disposals of antibiotics to the environment have increased emergence of various antibiotic resistance. One of the sources for the spread of antibiotic resistance is wastewater treatment plant, where bacteria and antibiotics can come in contact and can acquire antibiotics resistance. There are very few studies on this subject from a small town sewage treatment plant. Therefore, this study was conducted using raw sewage as well as treated sewage from a sewage treatment plant in Thibodaux in rural southeast Louisiana in USA. Samples were collected monthly from the Thibodaux sewage treatment plant and the presence of antibiotic resistance genes was monitored. The study showed the presence of antibiotic resistance genes in both raw and treated sewage in every month of the study period. The genetic transformation assay showed the successful transformation of methicillin resistant gene, mecA to an antibiotic sensitive Staphylococcus aureus, which became antibiotic resistant within 24h. Copyright © 2015 Elsevier Ltd. All rights reserved.

Antibiotic resistances of intestinal lactobacilli isolated from wild boars.

PubMed

Klose, Viviana; Bayer, Katharina; Kern, Corinna; Goelß, Florian; Fibi, Silvia; Wegl, Gertrude

2014-01-10

Acquired antibiotic resistances have been reported in lactobacilli of various animal and food sources, but there are no data from wild boar. The objective was a preliminary examination of the antibiotic resistance prevalence of intrinsically vancomycin-resistant lactobacilli isolated from wild boar intestines and analysis of the genetic determinants implicated. Out of three wild boars, 121 lactobacilli were recovered and grouped according to their whole cell protein patterns. Initial phenotypic screening revealed that all were susceptible to erythromycin (2 μg/ml), but 30 were resistant to tetracycline (32 μg/ml). Based on Randomly Amplified Polymorphic DNA-PCR clustering, 64 strains were selected as representative genotypes for identification and minimum inhibitory concentration (MIC) determination. Partial 16S rRNA gene sequencing identified four species: (i) L. mucosae (n=57), (ii) L. reuteri (n=47), (iii) L. fermentum (n=12), and (iv) L. murinus (n=5). Most heterofermentative strains displayed low MICs for ampicillin (AMP), chloramphenicol (CHL), streptomycin (STR), kanamycin (KAN), gentamicin (GEN), erythromycin (ERY), quinupristin/dalfopristin (Q/D), and clindamycin (CLI). Atypical MICs were found mainly in L. mucosae and L. reuteri for TET, KAN, STR, AMP and CHL, but except the TET MICs of L. mucosae mostly at low level. L. murinus strains revealed atypical MICs for aminoglycosides, and/or CHL, AMP, CLI. PCR screening detected tet(W) in 12 and tet(M) in one of heterofermentative strains, as well as the aph(3')-III kanamycin gene in L. murinus. This is the first report showing acquired antibiotic resistance determinants in intestinal lactobacilli of wild boar origin. Copyright © 2013 Elsevier B.V. All rights reserved.

Plant Growth, Antibiotic Uptake, and Prevalence of Antibiotic Resistance in an Endophytic System of Pakchoi under Antibiotic Exposure

PubMed Central

Zhang, Hao; Li, Xunan; Yang, Qingxiang; Sun, Linlin; Yang, Xinxin; Zhou, Mingming; Deng, Rongzhen; Bi, Linqian

2017-01-01

Antibiotic contamination in agroecosystems may cause serious problems, such as the proliferation of various antibiotic resistant bacteria and the spreading of antibiotic resistance genes (ARGs) in the environment or even to human beings. However, it is unclear whether environmental antibiotics, antibiotic resistant bacteria, and ARGs can directly enter into, or occur in, the endophytic systems of plants exposed to pollutants. In this study, a hydroponic experiment exposing pakchoi (Brassica chinensis L.) to tetracycline, cephalexin, and sulfamethoxazole at 50% minimum inhibitory concentration (MIC) levels and MIC levels, respectively, was conducted to explore plant growth, antibiotic uptake, and the development of antibiotic resistance in endophytic systems. The three antibiotics promoted pakchoi growth at 50% MIC values. Target antibiotics at concentrations ranging from 6.9 to 48.1 µg·kg−1 were detected in the treated vegetables. Additionally, the rates of antibiotic-resistant endophytic bacteria to total cultivable endophytic bacteria significantly increased as the antibiotics accumulated in the plants. The detection and quantification of ARGs indicated that four types, tetX, blaCTX-M, and sul1 and sul2, which correspond to tetracycline, cephalexin, and sulfamethoxazole resistance, respectively, were present in the pakchoi endophytic system and increased with the antibiotic concentrations. The results highlight a potential risk of the development and spread of antibiotic resistance in vegetable endophytic systems. PMID:29099753

Plant Growth, Antibiotic Uptake, and Prevalence of Antibiotic Resistance in an Endophytic System of Pakchoi under Antibiotic Exposure.

PubMed

Zhang, Hao; Li, Xunan; Yang, Qingxiang; Sun, Linlin; Yang, Xinxin; Zhou, Mingming; Deng, Rongzhen; Bi, Linqian

2017-11-03

Antibiotic contamination in agroecosystems may cause serious problems, such as the proliferation of various antibiotic resistant bacteria and the spreading of antibiotic resistance genes (ARGs) in the environment or even to human beings. However, it is unclear whether environmental antibiotics, antibiotic resistant bacteria, and ARGs can directly enter into, or occur in, the endophytic systems of plants exposed to pollutants. In this study, a hydroponic experiment exposing pakchoi ( Brassica chinensis L.) to tetracycline, cephalexin, and sulfamethoxazole at 50% minimum inhibitory concentration (MIC) levels and MIC levels, respectively, was conducted to explore plant growth, antibiotic uptake, and the development of antibiotic resistance in endophytic systems. The three antibiotics promoted pakchoi growth at 50% MIC values. Target antibiotics at concentrations ranging from 6.9 to 48.1 µg·kg -1 were detected in the treated vegetables. Additionally, the rates of antibiotic-resistant endophytic bacteria to total cultivable endophytic bacteria significantly increased as the antibiotics accumulated in the plants. The detection and quantification of ARGs indicated that four types, tet X, bla CTX-M , and sul 1 and sul 2, which correspond to tetracycline, cephalexin, and sulfamethoxazole resistance, respectively, were present in the pakchoi endophytic system and increased with the antibiotic concentrations. The results highlight a potential risk of the development and spread of antibiotic resistance in vegetable endophytic systems.

Assessment of competitiveness of rhizobia infecting Galega orientalis on the basis of plant yield, nodulation, and strain identification by antibiotic resistance and PCR.

PubMed

Tas, E; Leinonen, P; Saano, A; Räsänen, L A; Kaijalainen, S; Piippola, S; Hakola, S; Lindström, K

1996-02-01

Competition between effective and ineffective Rhizobium galegae strains nodulating Galega orientalis was examined on the basis of plant growth, nodulation, antibiotic resistance, and PCR results. In a preliminary experiment in Leonard's jars, ineffective R. galegae strains HAMBI 1207 and HAMBI 1209 competed in similar manners with the effective strain R. galegae HAMBI 1174. In a pot experiment, soil was inoculated with 0 to 10(5) HAMBI 1207 cells per g before G. orientalis was sown. Seeds of G. orientalis were surface inoculated with 2 x 10(4) and 2 x 10(5) cells of HAMBI 1174 per seed (which represent half and fivefold the commercially recommended amount of inoculant, respectively). Plant yield and nodulation by the effective strain were significantly reduced, with as few as 10(2) ineffective rhizobia per g of soil, and the inoculation response was not improved by the 10-fold greater dose of the inoculant. Bacteria occupying the nodules were identified by antibiotic resistance and PCR with primers specific for R. galegae HAMBI 1174, R. galegae, and genes coding for bacterial 16S rRNA (bacterial 16S rDNA). Sixty-two large nodules examined were occupied by the effective strain HAMBI 1174, as proven by antibiotic resistance and amplification of the strain-specific fragment. From 20 small nodules, only the species-specific fragment could be amplified, and isolated bacteria had the same antibiotic resistance and 16S PCR restriction pattern as strain HAMBI 1207. PCR with our strain-specific and species-specific primers provides a powerful tool for strain identification of R. galegae directly from nodules without genetic modification of the bacteria.

Aerobic composting reduces antibiotic resistance genes in cattle manure and the resistome dissemination in agricultural soils.

PubMed

Gou, Min; Hu, Hang-Wei; Zhang, Yu-Jing; Wang, Jun-Tao; Hayden, Helen; Tang, Yue-Qin; He, Ji-Zheng

2018-01-15

Composting has been suggested as a potential strategy to eliminate antibiotic residues and pathogens in livestock manure before its application as an organic fertilizer in agro-ecosystems. However, the impacts of composting on antibiotic resistance genes (ARGs) in livestock manure and their temporal succession following the application of compost to land are not well understood. We examined how aerobic composting affected the resistome profiles of cattle manure, and by constructing laboratory microcosms we compared the effects of manure and compost application to agricultural soils on the temporal succession of a wide spectrum of ARGs. The high-throughput quantitative PCR array detected a total of 144 ARGs across all the soil, manure and compost samples, with Macrolide-Lincosamide-Streptogramin B, aminoglycoside, multidrug, tetracycline, and β-lactam resistance as the most dominant types. Composting significantly reduced the diversity and relative abundance of ARGs and mobile genetic elements (MGEs) in the cattle manure. In the 120-day microcosm incubation, the diversity and abundance of ARGs in manure-treated soils were significantly higher than those in compost-treated soils at the beginning of the experiment. The level of antibiotic resistance rapidly declined over time in all manure- and compost-treated soils, coupled with similar temporal patterns of manure- and compost-derived bacterial communities as revealed by SourceTracker analysis. The network analysis revealed more intensive interactions/associations among ARGs and MGEs in manure-treated soils than in compost-treated soils, suggesting that mobility potential of ARGs was lower in soils amended with compost. Our results provide evidence that aerobic composting of cattle manure may be an effective approach to mitigate the risk of antibiotic resistance propagation associated with land application of organic wastes. Copyright © 2017 Elsevier B.V. All rights reserved.

An evolutionary model to predict the frequency of antibiotic resistance under seasonal antibiotic use, and an application to Streptococcus pneumoniae

PubMed Central

Lehtinen, Sonja; Fraser, Christophe

2017-01-01

The frequency of resistance to antibiotics in Streptococcus pneumoniae has been stable over recent decades. For example, penicillin non-susceptibility in Europe has fluctuated between 12% and 16% without any major time trend. In spite of long-term stability, resistance fluctuates over short time scales, presumably in part due to seasonal fluctuations in antibiotic prescriptions. Here, we develop a model that describes the evolution of antibiotic resistance under selection by multiple antibiotics prescribed at seasonally changing rates. This model was inspired by, and fitted to, published data on monthly antibiotics prescriptions and frequency of resistance in two communities in Israel over 5 years. Seasonal fluctuations in antibiotic usage translate into small fluctuations of the frequency of resistance around the average value. We describe these dynamics using a perturbation approach that encapsulates all ecological and evolutionary forces into a generic model, whose parameters quantify a force stabilizing the frequency of resistance around the equilibrium and the sensitivity of the population to antibiotic selection. Fitting the model to the data revealed a strong stabilizing force, typically two to five times stronger than direct selection due to antibiotics. The strong stabilizing force explains that resistance fluctuates in phase with usage, as antibiotic selection alone would result in resistance fluctuating behind usage with a lag of three months when antibiotic use is seasonal. While most antibiotics selected for increased resistance, intriguingly, cephalosporins selected for decreased resistance to penicillins and macrolides, an effect consistent in the two communities. One extra monthly prescription of cephalosporins per 1000 children decreased the frequency of penicillin-resistant strains by 1.7%. This model emerges under minimal assumptions, quantifies the forces acting on resistance and explains up to 43% of the temporal variation in resistance. PMID:28566489

Probiotic approach to prevent antibiotic resistance.

PubMed

Ouwehand, Arthur C; Forssten, Sofia; Hibberd, Ashley A; Lyra, Anna; Stahl, Buffy

2016-01-01

Probiotics are live microorganisms, mainly belonging to the genera Lactobacillus and Bifidobacterium, although also strain of other species are commercialized, that have a beneficial effect on the host. From the perspective of antibiotic use, probiotics have been observed to reduce the risk of certain infectious disease such as certain types of diarrhea and respiratory tract infection. This may be accompanied with a reduced need of antibiotics for secondary infections. Antibiotics tend to be effective against most common diseases, but increasingly resistance is being observed among pathogens. Probiotics are specifically selected to not contribute to the spread of antibiotic resistance and not carry transferable antibiotic resistance. Concomitant use of probiotics with antibiotics has been observed to reduce the incidence, duration and/or severity of antibiotic-associated diarrhea. This contributes to better adherence to the antibiotic prescription and thereby reduces the evolution of resistance. To what extent probiotics directly reduce the spread of antibiotic resistance is still much under investigation; but maintaining a balanced microbiota during antibiotic use may certainly provide opportunities for reducing the spread of resistances. Key messages Probiotics may reduce the risk for certain infectious diseases and thereby reduce the need for antibiotics. Probiotics may reduce the risk for antibiotic-associated diarrhea Probiotics do not contribute to the spread of antibiotic resistance and may even reduce it.

Soil types influence the fate of antibiotic-resistant bacteria and antibiotic resistance genes following the land application of sludge composts.

PubMed

Zhang, Junya; Sui, Qianwen; Tong, Juan; Zhong, Hui; Wang, Yawei; Chen, Meixue; Wei, Yuansong

2018-05-21

Sewage sludge was generally considered a significant reservoir of antibiotic resistance genes (ARGs) and could enter agricultural systems as fertilizer after composting. Soil types and the discrepancy of sludge composts could have influenced the fate of antibiotic-resistant bacteria (ARB) following the land application of sludge composts, which deserved to be clarified. Thus, the fate of ARB and ARGs following the land application of three types of sludge composts (A, B, and C) to three different soils (red soil, loess, and black soil) was investigated. The results showed that tetX, which was enriched the most during composting, did not affect the soil resistome, whereas tetG did. Soil types influenced the dynamics of ARB and ARGs significantly, whereas no significant difference was observed among compost types. The advantage of reducing ARGs during the composting process in compost B did not extend to land application. Land application of composts influenced the microbial community significantly at the early stage, but the microbial community returned to the control pattern gradually. Changes in the microbial community contributed more to the dynamics of ARGs in red and black soil compared with other factors, including co-selection from heavy metals, horizontal gene transfer, biomass and environmental factors, whereas horizontal gene transfer, reflected by intI1 levels, contributed the most in loess. Copyright © 2018 Elsevier Ltd. All rights reserved.

The role of healthcare strategies in controlling antibiotic resistance.

PubMed

Aziz, Ann-Marie

In an interview in March 2013, the Chief Medical Officer described antibiotic resistance as a 'ticking time bomb' and ranked it along with terrorism on a list of threats to the nation. Her report Infections and the Rise of Antimicrobial Resistance (Department of Health, 2011) highlighted that, while a new infectious disease has been discovered nearly every year over the past three decades, there have been very few new antibiotics developed, leaving our armoury nearly empty. Antibiotic resistance is a universal problem that needs to be tackled by a wide variety of strategies and players. Our approach to tackling resistance to antibiotic agents must therefore also be dynamic. As well as reducing environmental use, we also need to lower antibiotic use in the healthcare setting. Healthcare workers have a huge role to play in combating antibiotic resistance. This article focuses on several issues related to antibiotic resistance, including antibiotic modes of action and the properties that confer resistance on bacteria. It includes information on antibiotic usage and describes current healthcare strategies we can adopt to help reduce the development of resistance.

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.

Genomic and metagenomic diversity of antibiotic resistance in dairy animals

USDA-ARS?s Scientific Manuscript database

Antibiotic resistance in food animals has received increased scrutiny in recent years due to the increased prevalence of antibiotic resistant infections in the human clinical setting. The extent to which antibiotic usage in food animals is responsible for the burden of antibiotic resistance in human...

Sampling and Pooling Methods for Capturing Herd Level Antibiotic Resistance in Swine Feces using qPCR and CFU Approaches

PubMed Central

Mellerup, Anders; Ståhl, Marie

2015-01-01

The aim of this article was to define the sampling level and method combination that captures antibiotic resistance at pig herd level utilizing qPCR antibiotic resistance gene quantification and culture-based quantification of antibiotic resistant coliform indicator bacteria. Fourteen qPCR assays for commonly detected antibiotic resistance genes were developed, and used to quantify antibiotic resistance genes in total DNA from swine fecal samples that were obtained using different sampling and pooling methods. In parallel, the number of antibiotic resistant coliform indicator bacteria was determined in the same swine fecal samples. The results showed that the qPCR assays were capable of detecting differences in antibiotic resistance levels in individual animals that the coliform bacteria colony forming units (CFU) could not. Also, the qPCR assays more accurately quantified antibiotic resistance genes when comparing individual sampling and pooling methods. qPCR on pooled samples was found to be a good representative for the general resistance level in a pig herd compared to the coliform CFU counts. It had significantly reduced relative standard deviations compared to coliform CFU counts in the same samples, and therefore differences in antibiotic resistance levels between samples were more readily detected. To our knowledge, this is the first study to describe sampling and pooling methods for qPCR quantification of antibiotic resistance genes in total DNA extracted from swine feces. PMID:26114765

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.

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

PubMed Central

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

2017-01-01

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

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

PubMed

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

2017-01-01

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

The expression of antibiotic resistance genes in antibiotic-producing bacteria.

PubMed

Mak, Stefanie; Xu, Ye; Nodwell, Justin R

2014-08-01

Antibiotic-producing bacteria encode antibiotic resistance genes that protect them from the biologically active molecules that they produce. The expression of these genes needs to occur in a timely manner: either in advance of or concomitantly with biosynthesis. It appears that there have been at least two general solutions to this problem. In many cases, the expression of resistance genes is tightly linked to that of antibiotic biosynthetic genes. In others, the resistance genes can be induced by their cognate antibiotics or by intermediate molecules from their biosynthetic pathways. The regulatory mechanisms that couple resistance to antibiotic biosynthesis are mechanistically diverse and potentially relevant to the origins of clinical antibiotic resistance. © 2014 John Wiley & Sons Ltd.

Residual antibiotics, antibiotic resistant superbugs and antibiotic resistance genes in surface water catchments: Public health impact

NASA Astrophysics Data System (ADS)

Anthony A, Adegoke; Adekunle C, Faleye; Thor A, Stenstrӧm

2018-06-01

Antibiotics are released to the surface water through different routes, like for example the wastewater treatment plants, from human and animal metabolic waste, agriculture run off, industrial antibiotic waste. The release of the antibiotics to the water catchment and/or the environments in sub-lethal concentrations for the microorganisms lead to the emergence of antibiotic resistance (AR) and selection for antibiotic resistance genes (ARGs). The bacteria utilize their quorum sensing to form biofilm within which ARGs are transferred from antibiotic resistant bacteria (ARB) to the susceptible strains, conferring resistance on them. This has contributed substantially to the growing trend of resistance from multiple antibiotic resistance to extended spectrum resistance, extreme resistance and recently to total antibiotic resistance. The antibiotics, ARB, ARGs are sometimes internalized into the crops irrigated with the surface water returning the bacteria to human in a difficult to control form. While quorum quenching strategy is being advocated during treatment of wastewater to disrupt biofilm as well as the spread of resistance, intermittent check for effectiveness of treatment of wastewater before release into receiving water bodies is hereby advocated. To achieve this, there is the need for better measurements, surveillance and follow-up and thereby the further needs to incorporate more integrative (multidisciplinary) approaches and state of the art tools, for appropriate detection and action. This presentation is to critically review the effect of antibiotic release, ARGs, ARB in water catchment on other water related applications in Southern African countries in relation to other part of the world.

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.

Next-generation approaches to understand and combat the antibiotic resistome

PubMed Central

Crofts, Terence S.; Gasparrini, Andrew J.; Dantas, Gautam

2017-01-01

Antibiotic resistance is a natural feature of diverse microbial ecosystems. Although recent studies of the antibiotic resistome have highlighted barriers to the horizontal transfer of antibiotic resistance genes between habitats, the rapid global spread of genes that confer resistance to carbapenem, colistin and quinolone antibiotics illustrates the dire clinical and societal consequences of such events. Over time, the study of antibiotic resistance has grown from focusing on single pathogenic organisms in axenic culture to studying antibiotic resistance in pathogenic, commensal and environmental bacteria at the level of microbial communities. As the study of antibiotic resistance advances, it is important to incorporate this comprehensive approach to better inform global antibiotic resistance surveillance and antibiotic development. It is increasingly becoming apparent that although not all resistance genes are likely to geographically and phylogenetically disseminate, the threat presented by those that are is serious and warrants an interdisciplinary research focus. In this Review, we highlight seminal work in the resistome field, discuss recent advances in the studies of resistomes, and propose a resistome paradigm that can pave the way for the improved proactive identification and mitigation of emerging antibiotic resistance threats. PMID:28392565

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

PubMed

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

2000-07-01

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

Antibiotics involved in the occurrence of antibiotic-resistant bacteria: a nationwide multilevel study suggests differences within antibiotic classes.

PubMed

Gbaguidi-Haore, Houssein; Dumartin, Catherine; L'Hériteau, François; Péfau, Muriel; Hocquet, Didier; Rogues, Anne-Marie; Bertrand, Xavier

2013-02-01

To identify the antibiotics potentially the most involved in the occurrence of antibiotic-resistant bacteria from an ecological perspective in French healthcare facilities (HCFs). This study was based on data from the French antimicrobial surveillance network (ATB-RAISIN, 2007-09). Antibiotics were expressed in defined daily doses per 1000 patient-days. Antibiotic-resistant bacteria were considered as count data adjusted for patient-days. These were third-generation cephalosporin (3GC)- and ciprofloxacin-resistant Escherichia coli, cefotaxime-resistant Enterobacter cloacae, methicillin-resistant Staphylococcus aureus and ceftazidime-, imipenem- and ciprofloxacin-resistant Pseudomonas aeruginosa. Three-level negative binomial regression models were built to take into account the hierarchical structure of data: level 1, repeated measures each year (count outcome, time, antibiotics); level 2, HCFs (type and size); and level 3, regions (geographical area). A total of 701 HCFs from 20 French regions and up to 1339 HCF-years were analysed. The use of ceftriaxone, but not of cefotaxime, was positively correlated with incidence rates of 3GC- and ciprofloxacin-resistant E. coli. In contrast, both 3GCs were positively correlated with the incidence rate of cefotaxime-resistant E. cloacae. Higher levels of use of ciprofloxacin and/or ofloxacin, but not of levofloxacin, were associated with higher incidence rates of 3GC- and ciprofloxacin-resistant E. coli, cefotaxime-resistant E. cloacae, methicillin-resistant S. aureus and ceftazidime- and ciprofloxacin-resistant P. aeruginosa. Our study suggests differences within antibiotic classes in promoting antibiotic resistance. We identified ceftriaxone, ciprofloxacin and ofloxacin as priority targets in public health strategies designed to reduce antibiotic use and antibiotic-resistant bacteria in French HCFs.

Occurrence of antibiotic resistance and characterization of resistant genes and integrons in Enterobacteriaceae isolated from integrated fish farms south China

USGS Publications Warehouse

Su, Hao-Chang; Ying, Guang-Guo; Tao, Ran; Zhang, Rui-Quan; Fogarty, Lisa R.; Kolpin, Dana W.

2011-01-01

Antibiotics are still widely applied in animal husbandry to prevent diseases and used as feed additives to promote animal growth. This could result in antibiotic resistance to bacteria and antibiotic residues in animals. In this paper, Enterobacteriaceae isolated from four integrated fish farms in Zhongshan, South China were tested for antibiotic resistance, tetracycline resistance genes, sulfonamide resistance genes, and class 1 integrons. The Kirby-Bauer disk diffusion method and polymerase chain reaction (PCR) assays were carried out to test antibiotic susceptibility and resistance genes, respectively. Relatively high antibiotic resistance frequencies were found, especially for ampicillin (80%), tetracycline (52%), and trimethoprim (50%). Out of 203 Enterobacteriaceae isolates, 98.5% were resistant to one or more antibiotics tested. Multiple antibiotic resistance (MAR) was found highest in animal manures with a MAR index of 0.56. Tetracycline resistance genes (tet(A), tet(C)) and sulfonamide resistance genes (sul2) were detected in more than 50% of the isolates. The intI1 gene was found in 170 isolates (83.7%). Both classic and non-classic class 1 integrons were found. Four genes, aadA5, aadA22, dfr2, and dfrA17, were detected. To our knowledge, this is the first report for molecular characterization of antibiotic resistance genes in Enterobacteriaceae isolated from integrated fish farms in China and the first time that gene cassette array dfrA17-aadA5 has been detected in such fish farms. Results of this study indicated that fish farms may be a reservoir of highly diverse and abundant antibiotic resistant genes and gene cassettes. Integrons may play a key role in multiple antibiotic resistances posing potential health risks to the general public and aquaculture.

Monitoring of resistance genes in Listeria monocytogenes isolates and their presence in the extracellular DNA of biofilms: a case study from the Czech Republic.

PubMed

Boháčová, Martina; Zdeňková, Kamila; Tomáštíková, Zuzana; Fuchsová, Viviana; Demnerová, Kateřina; Karpíšková, Renáta; Pazlarová, Jarmila

2018-04-21

The alarming occurrence of antibiotic resistance genes in food production demands continuous monitoring worldwide. One reservoir of resistance genes is thought to be eDNA. There is currently little available information in Europe about either the extracellular DNA distribution of the bacterium or the spread of resistance genes in L. monocytogenes. Therefore, our aims were to give insight into the Listeria monocytogenes resistance situation in the Czech Republic and assess the presence of resistance genes in their extracellular DNA (eDNA). First, susceptibility tests were performed on 49 isolates of L. monocytogenes with selected antibiotics. Next, we tested DNA of suspected isolates for the presence of resistance genes in both planktonic cells and the eDNA of biofilms. Finally, fluorescent confocal microscopy was used to observe the eDNA pattern of selected isolates under conditions that mimicked the food processing environment and the human body. Susceptibility tests found isolates intermediate resistant to chloramphenicol, tetracycline, and ciprofloxacin as well as isolates resistant to ciprofloxacin. For all suspected isolates, PCR confirmed the presence of the gene lde encoding efflux pump in both types of DNA. When the biofilm was observed using confocal laser scanning microscope, the eDNA distribution patterns varied considerably according to the culture conditions. Furthermore, the food and clinical isolates varied in terms of the amount of eDNA detected. The presence of an efflux pump in both types of DNA suggests that the eDNA might serve as a reservoir of resistance genes. Surprising differences were observed in the eDNA pattern. Our results suggest that the current risk of the spread of L. monocytogenes resistance genes is low in the Czech Republic, but they also indicate the need for continuous long-term monitoring of the situation.

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.

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

DOWN-STREAM SPATIAL DISTRIBUTION OF ANTIBIOTIC RESISTANCE TRAITS ALONG METAL CONTAMINATED STREAM REACHES

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

Tuckfield, C; J V Mcarthur

2007-04-16

Sediment bacteria samples were collected from three streams in South Carolina, two contaminated with multiple metals (Four Mile Creek and Castor Creek), one uncontaminated (Meyers Branch), and another metal contaminated stream (Lampert Creek) in northern Washington State. Growth plates inoculated with Four Mile Creek sample extracts show bacteria colony growth after incubation on plates containing either one of two aminoglycosides (kanamycin or streptomycin), tetracycline or chloramphenocol. This study analyzes the spatial pattern of antibiotic resistance in culturable sediment bacteria in all four streams that may be due to metal contamination. We summarize the two aminoglycoside resistance measures and the 10more » metals concentrations by Principal Components Analysis. Respectively, 63% and 58% of the variability was explained in the 1st principal component of each variable set. We used the respective multivariate summary metrics (i.e. 1st principal component scores) as input measures for exploring the spatial correlation between antibiotic resistance and metal concentration for each stream reach sampled. Results show a significant and negative correlation between metals scores versus aminoglycoside resistance scores and suggest that selection for metal tolerance among sediment bacteria may influence selection for antibiotic resistance differently than previously supposed.. In addition, we borrow a method from geostatistics (variography) wherein a spatial cross-correlation analysis shows that decreasing metal concentrations scores are associated with increasing aminoglycoside resistance scores as the separation distance between sediment samples decreases, but for contaminated streams only. Since these results were counter to our initial expectation and to other experimental evidence for water column bacteria, we suspect our field results are influenced by metal bioavailability in the sediments and by a contaminant promoted interaction or ''cocktail effect'' from complex combinations of pollution mediated selection agents.« less

Evidence for Environmental Dissemination of Antibiotic Resistance Mediated by Wild Birds.

PubMed

Wu, Jiao; Huang, Ye; Rao, Dawei; Zhang, Yongkui; Yang, Kun

2018-01-01

The aquatic bird, egret, could carry antibiotic resistance (AR) from a contaminated waterway (Jin River, Chengdu, China) into the surrounding environment (Wangjianglou Park). A systematic study was carried out on the unique environmental dissemination mode of AR mediated by birds. The minimum inhibitory concentrations of various antibiotics against the environmental Escherichia coli isolates were used to evaluate the bacterial AR at the environmental locations where these isolates were recovered, i.e., the Jin River water, the egret feces, the park soil, and the campus soil. The level of AR in the park soil was significantly higher than that in the campus soil that was seldom affected by the egrets, which suggested that the egrets mediated the transportation of AR from the polluted waterway to the park. Genotyping of the resistant E. coli isolates via repetitive-element PCR gave no strong correlation between the genotypes and the AR patterns of the bacteria. So, the transfer of resistant strains should not be the main mode of AR transportation in this process. The results of real-time PCR revealed that the abundance of antibiotic resistance genes (ARGs) and mobile genetic element (MGE) sequences (transposase and integrase genes) declined along the putative transportation route. The transportation of ARGs could be due to their linkage with MGE sequences, and horizontal gene transfer should have contributed to the process. The movable colistin-resistance gene mcr-1 was detected among the colistin-resistant E. coli strains isolated from the river water and the egret feces, which indicated the possibility of the environmental dissemination of this gene. Birds, especially the migratory birds, for the role they played on the dissemination of environmental AR, should be considered when studying the ecology of AR.

[Antimicrobial susceptibility of Pseudomonas aeruginosa isolated in Fukushima Prefecture].

PubMed

Niitsuma, K; Saitoh, M; Kojimabara, M; Kashiwabara, N; Aoki, T; Tomizawa, M; Maeda, J; Kosenda, T

2001-02-01

We investigated the susceptibility of Pseudomonas aeruginosa (isolated from the sputum of patients with respiratory infection in 4 medical institutions in Fukushima Prefecture) to 8 beta-lactam antibiotics including three carbapenems and relationships among MICs of antibiotics tested. The MIC90 values for a total of 216 strains were 6.25 micrograms/ml for meropenem, 12.5 micrograms/ml for imipenem and ceftazidime, 25 micrograms/ml for panipenem and cefsulodin, 50 micrograms/ml for cefpirome and over than 200 micrograms/ml for cefoperazone and piperacillin. The frequency of resistance of these strains to each antibiotic was as follows: The resistant strains were 19 (8.8%) for meropenem, 34 (15.7%) for imipenem and ceftazidime, 50 (23.1%) for cefsulodin, 72 (33.3%) for panipenem, 76 (35.2%) for piperacillin and 90 (41.7%) for cefpirome. Eighteen strains (18.3%) of 19 meropenem resitant straisn were resistant to imipenem and panipenem, but 16 strains of the 34 imipenem-resistant strains and 54 strains of the 72 panipenem-resistant strains were susceptible to meropenem. In investigation of isolation of multi-resistant Pseudomonas aeruginosa, the susceptibility of strains tested to 7 antibiotics except cefoperazone was as follows: The strains susceptible to all the 7 antibiotics were 92 strains (42.6%), and 33 strains (15.2%) were resistant to 2 antibiotics, 31 strains (14.4%) were resistant to 1 antibiotic, 21 strains (9.7%) were resistant to 3 antibiotics, 13 strains (6.0%) were resistant to 5 antibiotics, 9 (4.2%) were resistant to 4 and 7 antibiotics, and 8 strains (3.7%) were reistant to 6 antibiotics. Since the emergence of these multi-resistant strains is closely related to frequent use of antibiotics for nosocomial infections, special attention should be paid to the antimicrobial susceptibility of Pseudomonas aeruginosa and the situation of antibiotic resistant strains.

Evaluation of levels of antibiotic resistance in groundwater-derived E. coli isolates in the Midwest of Ireland and elucidation of potential predictors of resistance

NASA Astrophysics Data System (ADS)

O'Dwyer, Jean; Hynds, Paul; Pot, Matthieu; Adley, Catherine C.; Ryan, Michael P.

2017-06-01

Antibiotic-resistant (pathogenic and non-pathogenic) organisms and genes are now acknowledged as significant emerging aquatic contaminants with potentially adverse human and ecological health impacts, and thus require monitoring. This study is the first to investigate levels of resistance among Irish groundwater (private wells) samples; Escherichia coli isolates were examined against a panel of commonly prescribed human and veterinary therapeutic antibiotics, followed by determination of the causative factors of resistance. Overall, 42 confirmed E. coli isolates were recovered from a groundwater-sampling cohort. Resistance to the human panel of antibiotics was moderate; nine (21.4%) E. coli isolates demonstrated resistance to one or more human antibiotics. Conversely, extremely high levels of resistance to veterinary antibiotics were found, with all isolates presenting resistance to one or more veterinary antibiotics. Particularly high levels of resistance (93%) were found with respect to the aminoglycoside class of antibiotics. Results of statistical analysis indicate a significant association between the presence of human (multiple) antibiotic resistance ( p = 0.002-0.011) and both septic tank density and the presence of vulnerable sub-populations (<5 years). For the veterinary antibiotics, results point to a significant relationship ( p = <0.001) between livestock (cattle) density and the prevalence of multiple antibiotic resistant E. coli. Groundwater continues to be an important resource in Ireland, particularly in rural areas; thus, results of this preliminary study offer a valuable insight into the prevalence of antibiotic resistance in the hydrogeological environment and establish a need for further research with a larger geological diversity.

Danger of Antibiotic Overuse (For Parents)

MedlinePlus

... against them. This is called bacterial resistance or antibiotic resistance. Treating these resistant bacteria requires higher doses of ... to even the most powerful antibiotics available today. Antibiotic resistance is a widespread problem, and one that the ...

The drinking water treatment process as a potential source of affecting the bacterial antibiotic resistance.

PubMed

Bai, Xiaohui; Ma, Xiaolin; Xu, Fengming; Li, Jing; Zhang, Hang; Xiao, Xiang

2015-11-15

Two waterworks, with source water derived from the Huangpu or Yangtze River in Shanghai, were investigated, and the effluents were plate-screened for antibiotic-resistant bacteria (ARB) using five antibiotics: ampicillin (AMP), kanamycin (KAN), rifampicin (RFP), chloramphenicol (CM) and streptomycin (STR). The influence of water treatment procedures on the bacterial antibiotic resistance rate and the changes that bacteria underwent when exposed to the five antibiotics at concentration levels ranging from 1 to 100 μg/mL were studied. Multi-drug resistance was also analyzed using drug sensitivity tests. The results indicated that bacteria derived from water treatment plant effluent that used the Huangpu River rather than the Yangtze River as source water exhibited higher antibiotic resistance rates against AMP, STR, RFP and CM but lower antibiotic resistance rates against KAN. When the antibiotic concentration levels ranged from 1 to 10 μg/mL, the antibiotic resistance rates of the bacteria in the water increased as water treatment progressed. Biological activated carbon (BAC) filtration played a key role in increasing the antibiotic resistance rate of bacteria. Chloramine disinfection can enhance antibiotic resistance. Among the isolated ARB, 75% were resistant to multiple antibiotics. Ozone oxidation, BAC filtration and chloramine disinfection can greatly affect the relative abundance of bacteria in the community. Copyright © 2015 Elsevier B.V. All rights reserved.

In vitro selection of Staphylococcus aureus mutants resistant to tigecycline with intermediate susceptibility to vancomycin.

PubMed

Herrera, Melina; Di Gregorio, Sabrina; Fernandez, Silvina; Posse, Graciela; Mollerach, Marta; Di Conza, José

2016-03-08

Tigecycline (TIG) is an antibiotic belonging to the glycylcyclines class and appears to be a good choice to fight infections caused by Staphylococcus aureus. To date, TIG exhibits good activity against this microorganism. The aim of this work was to obtain in vitro mutants of S. aureus resistant to TIG and evaluate possible changes in their susceptibility patterns to other antibiotics. Two mutants of S. aureus resistant to TIG (MIC = 16 µg/mL) were selected in vitro from clinical isolates of methicillin-resistant S. aureus. In both mutants, corresponding to different lineage (ST5 and ST239), an increase of efflux activity against TIG was detected. One mutant also showed a reduced susceptibility to vancomycin, corresponding to the VISA phenotype (MIC = 4 µg/mL), with a loss of functionality of the agr locus. The emergence of the VISA phenotype was accompanied by an increase in oxacillin and cefoxitin MICs. This study demonstrates that, under selective pressure, the increase of efflux activity in S. aureus is one of the mechanisms that may be involved in the emergence of tigecycline resistance. The emergence of this phenotype may eventually be associated to changes in susceptibility to other antibiotics such oxacillin and vancomycin.

The antibiotic resistome.

PubMed

Wright, Gerard D

2010-08-01

Antibiotics are essential for the treatment of bacterial infections and are among our most important drugs. Resistance has emerged to all classes of antibiotics in clinical use. Antibiotic resistance has, proven inevitable and very often it emerges rapidly after the introduction of a drug into the clinic. There is, therefore, a great interest in understanding the origins, scope and evolution of antibiotic resistance. The review discusses the concept of the antibiotic resistome, which is the collection of all genes that directly or indirectly contribute to antibiotic resistance. The review seeks to assemble current knowledge of the resistome concept as a means of understanding the totality of resistance and not just resistance in pathogenic bacteria. The concept of the antibiotic resistome provides a framework for the study and understanding of how resistance emerges and evolves. Furthermore, the study of the resistome reveals strategies that can be applied in new antibiotic discoveries.

First-Line Antimicrobial Resistance Patterns of Escherichia coli in Children With Urinary Tract Infection in Emergency Department and Primary Care Clinics.

PubMed

Ahmed, M Nadeem; Vannoy, Debby; Frederick, Ann; Chang, Sandy; Lawler, Elisabeth

2016-01-01

To identify risk factors for antibiotic resistance to Escherichia coli (E. coli) in children with urinary tract infections (UTIs) in emergency room and primary care clinics. This is a cross-sectional study of children 0 to 18 years of age reported to have E coli-positive UTIs whose medical and laboratory records were systematically reviewed. Compared with girls, boys were 2.29 times (confidence interval [CI] = 1.30-4.02) more likely to have E coli isolates resistant to ampicillin and 2 times more likely (CI = 1.13-3.62) to have isolates resistant to trimethoprim-sulfamethoxazole (TMP/SMX). Patients with genitourinary abnormalities were 1.57 times more likely to be resistant to ampicillin (CI = 1.03-2.41) and 1.86 times to TMP/SMX (CI = 1.18-2.94). Higher rates of ampicillin and TMP/SMX resistant urinary E coli isolates were observed among boys and children with a history of genitourinary abnormality. Age and recent antibiotic prescription are also potential risk factors for resistance. © The Author(s) 2015.

Bacteriology and Antibiogram of Urinary Tract Infection Among Female Patients in a Tertiary Health Facility in South Eastern Nigeria.

PubMed

Oli, Angus N; Akabueze, Vivian B; Ezeudu, Chijioke E; Eleje, George U; Ejiofor, Obiora S; Ezebialu, Ifeanyichukwu U; Oguejiofor, Charlotte B; Ekejindu, Ifeoma M; Emechebe, George O; Okeke, Kenneth N

2017-01-01

Urinary Tract Infection (UTI) is a common contagion among men and women with the incidence relatively higher among women due to their differing anatomy. An understanding of the kind of pathogens implicated in urinary tract infections as well as antibiotic susceptibility profiling may help the clinician make rationally correct empirical choice in their treatment. This study is aimed at determining the type and antibiotic susceptibility pattern of bacterial uropathogens isolated from female patients attending Chukwuemeka Odumegwu Ojukwu University Teaching Hospital (COOUTH), Awka, Nigeria. Two hundred and forty patients with clinically diagnosed UTI and who were on at least 5 days' antibiotic holiday were recruited into the study. Their demographic characteristics were captured using pre-tested questionnaire. Their clean catch mid-stream urine samples were collected using sterile universal container and sent to the Microbiology Department for processing. Within 30 minutes of samples collection, the specimens were cultured and the isolates were identified, after 24 h of incubation, using standard microbiological techniques. Antibiotic susceptibility tests were done with standard antibiotic discs using the Kirby-bauer disc diffusion method. Out of the 240 urine samples, 89.17% yielded significant bacteriuria. The pathogens implicated were Escherichia coli (28.5%), Staphylococcus aureus (28.0%), Salmonella spp (22.8%) and Pseudomonas aeruginosa (20.5%). HIV status, patients age, pregnancy status and marital status all significantly affected bacteriuria rate (p value < 0.05), while patients' location (sub-urban/rural dwelling), and level of education did not (p value > 0.05). The pattern of microbial resistance to antibiotics suggests that ceftazidime, fosfomycin and cefoxitin may not be used as first-line agents in the empirical treatment of UTIs rather; levofloxacin, meropenem or aztreonam should be considered. Levofloxacin was significantly effective against all the isolates and may be administered empirically while waiting for the culture result (Mean % susceptibility was 79.85). E. coli and S. aureus were the predominant pathogens in the study and many were resistant to the commonly prescribed antibiotics and so leave the clinicians with only few alternative drugs for UTIs treatment. Routine surveillance and monitoring studies need to be constantly conducted to update clinicians on the prevalent pathogens and the rational and empirical treatment of UTIs. Aggressive and consistent health education using every possible media is also recommended to combat the menace of drug resistance occasioned by inappropriate antibiotic use.

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

PubMed

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

2018-03-27

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

Effect of the selective pressure of sub-lethal level of heavy metals on the fate and distribution of ARGs in the catchment scale.

PubMed

Xu, Yan; Xu, Jian; Mao, Daqing; Luo, Yi

2017-01-01

Our previous study demonstrated that high levels of antibiotic resistance genes (ARGs) in the Haihe River were directly attributed to the excessive use of antibiotics in animal agriculture. The antibiotic residues of the Xiangjiang River determined in this study were much lower than those of the Haihe River, but the relative abundance of 16 detected ARGs (sul1, sul2 and sul3, qepA, qnrA, qnrB, qnrD and qnrS, tetA, tetB, tetW, tetM, tetQ and tetO, ermB and ermC), were as high as the Haihe River particularly in the downstream of the Xiangjiang River which is close to the extensive metal mining. The ARGs discharged from the pharmaceutical wastewater treatment plant (PWWTP) are a major source of ARGs in the upstream of the Xiangjiang River. In the downstream, selective stress of heavy metals rather than source release had a significant influence on the distinct distribution pattern of ARGs. Some heavy metals showed a positive correlation with certain ARG subtypes. Additionally, there is a positive correlation between individual ARG subtypes and heavy metal resistance genes, suggesting that heavy metals may co select the ARGs on the same plasmid of antibiotic resistant bacteria. The co-selection mechanism between specific metal and antibiotic resistance was further confirmed by these isolations encoding the resistance genotypes to antibiotics and metals. To our knowledge, this is the first study on the fate and distribution of ARGs under the selective pressure exerted by heavy metals in the catchment scale. These results are beneficial to understand the fate, and to discern the contributors of ARGs from either the source release or the selective pressure by sub-lethal levels of environmental stressors during their transport on a river catchment scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antibiotic Prescriptions in Critically-Ill Patients: A Latin American Experience

PubMed Central

Curcio, D

2013-01-01

Background: It is widely acknowledged that the presence of infection is an important outcome determinant for intensive care unit (ICU) patients. In fact, antibiotics are one of the most common therapies administered in the ICU settings. Aim: To evaluate the current usage of antibiotics in Latin American ICUs. Subjects and Methods: A one-day p-oint prevalence study to investigate the patterns of antibiotic was undertaken in 72 Latin American (LA) ICUs. Data was analyzed using the Statistix 8 statistical software, version 2.0 (USA). Results were expressed as proportions. When applicable, two tailed hypothesis testing for difference in proportions was used (Proportion Test); a P value of <0.05 was considered significant. Results: Of 704 patients admitted, 359 received antibiotic treatment on the day of the study (51%), of which 167/359 cases (46.5%) were due to hospital-acquired infections. The most frequent infection reorted was nosocomial pneumonia (74/359, 21%). Only in 264/359 patients (73.5%), cultures before starting antibiotic treatment were performed. Thirty-eight percent of the isolated microorganisms were Enterobacteriaceae extended-spectrum β-lactamase-producing, 11% methicillin-resistant Staphylococcus aureus and 10% carbapenems-resistant non-fermentative Gram-negatives. The antibiotics most frequently prescribed were carbapenems (125/359, 35%), alone or in combination with vancomycin or other antibiotic. There were no significant differences in the “restricted” antibiotic prescription (carbapenems, vancomycin, piperacillin–tazobactam, broad-spectrum cephalosporins, fluoroquinolones, tigecycline and linezolid) between patients with APACHE II score at the beginning of the antibiotic treatment <15 [83/114 (72.5%)] and ≥15 [179/245 (73%)] (P = 0.96). Only 29% of the antibiotic treatments were cultured directed (104/359). Conclusion: Carbapenems (alone or in combination) were the most frequently prescribed antibiotics in LA ICUs. However, the problem of carbapenem resistance in LA requires that physicians improve the use of this class of antibiotics. Our findings show that our web-based method for collection of one-day point prevalence was implemented successfully. However, based on the limitations of the model used, the results of this study must be taken with caution. PMID:23919194

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

PubMed Central

Mulla, Summaiya; Charan, Jaykaran; Rajdev, Sangita

2016-01-01

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

Genotypic and phenotypic β-lactam resistance and presence of PVL gene in Staphylococci from dry bovine udder

PubMed Central

Sivasailam, Asok; Sasidharan, Suchithra; Kollannur, Justin Davis; Syam, Radhika

2017-01-01

Dairy cows affected with subclinical mastitis can be sources of virulent, antimicrobial-resistant Staphylococci to humans because of the excretion of the bacteria through their milk. This study focussed on the phenotypic and genotypic antibiotic resistance patterns of Staphylococci isolated from dairy cows in early dry period. Among 96 isolates of Gram positive cocci from 157 cows, 76 were identified as Coagulase Negative Staphylococci and the remaining 20 were Staphylococcus aureus. Typical amplicons of coagulase gene were obtained for all 20 samples of S. aureus with three major coagulase types being identified as giving 627 bp (40%), 910 bp (35%) and 710 bp (25%) long PCR products. The groEL gene was amplified in PCR of all 76 isolates of Coagulase Negative Staphylococci, and incubation of PCR products with restriction enzyme PvuII yielded three distinct PCR-RFLP fragment patterns bearing resemblance to S. chromogenes and S. hyicus. Highest sensitivity of Coagulase Negative Staphylococci was noted for Azithromycin (92.5%) and the least to Tetracyclines (76.3%), whereas for S. aureus, it was Cefoperazone (95%) and Azithromycin (72.2%) respectively. Phenotypic resistance to Oxacillin (25 isolates), and Cefoxitin (11 isolates) was detected by dilution method with a commercial strip (Ezy MICTM). Genotypic resistance to β-Lactam antibiotics was found in 65 (34 with mecA gene and 31 with blaZ gene) isolates. Eighteen isolates possessed both the genes, with the PVL gene for virulence being detected in five of them. Nine isolates which had mecA gene were phenotypically susceptible to oxacillin while phenotypic resistance to oxacillin was observed in seven isolates that did not have either mecA or blaZ gene. This is the first report of persistent Staphylococcal infections possessing PVL gene and high level of genotypic resistance to β-Lactam antibiotics in small- holder dairy cattle from India. PMID:29091956

The scourge of antibiotic resistance: the important role of the environment.

PubMed

Finley, Rita L; Collignon, Peter; Larsson, D G Joakim; McEwen, Scott A; Li, Xian-Zhi; Gaze, William H; Reid-Smith, Richard; Timinouni, Mohammed; Graham, David W; Topp, Edward

2013-09-01

Antibiotic resistance and associated genes are ubiquitous and ancient, with most genes that encode resistance in human pathogens having originated in bacteria from the natural environment (eg, β-lactamases and fluoroquinolones resistance genes, such as qnr). The rapid evolution and spread of "new" antibiotic resistance genes has been enhanced by modern human activity and its influence on the environmental resistome. This highlights the importance of including the role of the environmental vectors, such as bacterial genetic diversity within soil and water, in resistance risk management. We need to take more steps to decrease the spread of resistance genes in environmental bacteria into human pathogens, to decrease the spread of resistant bacteria to people and animals via foodstuffs, wastes and water, and to minimize the levels of antibiotics and antibiotic-resistant bacteria introduced into the environment. Reducing this risk must include improved management of waste containing antibiotic residues and antibiotic-resistant microorganisms.

Resistance patterns of diversified phylogroups of Escherichia coli associated with mothers having history of preterm births in Pakistan.

PubMed

Rana, Fiza; Siddiqui, Sidra; Khan, Ayesha; Siddiqui, Fariha; Noreen, Zobia; Bokhari, Sadia; Bokhari, Habib

2017-01-01

Urinary tract infections (UTIs) are caused by extraintestinal pathogenic Escherichia coli (ExPEC), and are one of the key predictors of preterm births. In the light of this fact, present study was conducted to determine the predominant Escherichia coli (E. coli) phylotypes and their associated antibiotic susceptibility patterns, isolated from pregnant mothers with the history of preterm births. Forty seven E. coli strains were isolated out of a total of 80 urine samples of pregnant women. The isolates were phylotyped and further screened for the presence of Clonal group A. Moreover, Antimicrobial susceptibility testing and screening for Extended Spectrum Beta Lactamase (ESBL) producing strains were also performed. Among the 47 isolates, phylogroup B2 was found to be highly prevalent (45%), followed by group D (23%), B1 (10.64%), A (6.38%), E (6.38%), cryptic clade I (4.25%) and F (2.13%). Two isolates belonged to CgA and 41 (87.23%) isolates were found to be multidrug-resistant. Out of nine antibiotics tested in the study, the isolates displayed high resistance to Ampicillin (82.6%), Sulphamethoxazole (65.22%), Nalidixic acid (60.87%), Sulphamethoxazole-Trimethoprim, Doxycycline and Erythromycin (56.52% each). In total, 8 (17.02%) of the isolates were found to be ESBL positive. The prevalence of infections caused by virulent and highly drug resistant E. coli isolates constitute a risk of developing preterm birth complications in pregnant women and requires the selection of appropriate antibiotics for the treatment of infections caused during pregnancy.

RecA Inhibitors Potentiate Antibiotic Activity and Block Evolution of Antibiotic Resistance.

PubMed

Alam, Md Kausar; Alhhazmi, Areej; DeCoteau, John F; Luo, Yu; Geyer, C Ronald

2016-03-17

Antibiotic resistance arises from the maintenance of resistance mutations or genes acquired from the acquisition of adaptive de novo mutations or the transfer of resistance genes. Antibiotic resistance is acquired in response to antibiotic therapy by activating SOS-mediated DNA repair and mutagenesis and horizontal gene transfer pathways. Initiation of the SOS pathway promotes activation of RecA, inactivation of LexA repressor, and induction of SOS genes. Here, we have identified and characterized phthalocyanine tetrasulfonic acid RecA inhibitors that block antibiotic-induced activation of the SOS response. These inhibitors potentiate the activity of bactericidal antibiotics, including members of the quinolone, β-lactam, and aminoglycoside families in both Gram-negative and Gram-positive bacteria. They reduce the ability of bacteria to acquire antibiotic resistance mutations and to transfer mobile genetic elements conferring resistance. This study highlights the advantage of including RecA inhibitors in bactericidal antibiotic therapies and provides a new strategy for prolonging antibiotic shelf life. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Case Study on Soil Antibiotic Resistome in an Urban Community Garden.

PubMed

Mafiz, Abdullah Ibn; Perera, Liyanage Nirasha; He, Yingshu; Zhang, Wei; Xiao, Shujie; Hao, Weilong; Sun, Shi; Zhou, Kequan; Zhang, Yifan

2018-05-29

Urban agricultural soils can be an important reservoir of antibiotic resistance and have great food safety and public health indications. This study was to investigate antibiotic-resistant bacteria and antibiotic resistance genes in urban agricultural soils using phenotypic and metagenomic tools. A total of 207 soil bacteria were recovered from 41 soil samples collected from an urban agricultural garden in Detroit, USA. The most prevalent antibiotic resistance phenotypes demonstrated by Gram-negative bacteria was the resistance to ampicillin (94.2%), followed by chloramphenicol (80.0%), cefoxitin (79.5%), gentamicin (78.4%), and ceftriaxone (71.1%). Gram-positive bacteria were all resistant to gentamicin, kanamycin, and penicillin. Genes encoding resistance to quinolone, β-lactam, and tetracycline were the most prevalent and abundant in the soil. qepA and tetA, both encoding efflux pumps, predominated in quinolone and tetracycline resistance genes tested, respectively. Positive correlation (p < 0.05) was identified among groups of antibiotic resistance genes and between antibiotic resistance genes and metal resistance genes. The data demonstrated a diverse population of antibiotic resistance in urban agricultural soils. Phenotypic determination together with soil metagenomics proved to be a valuable tool to study the nature and extent of antibiotic resistance in the environment. Copyright © 2018. Published by Elsevier B.V.

[Antibiotic-resistant bacteria and new directions of antimicrobial chemotherapy].

PubMed

Tateda, Kazuhiro

2012-05-01

The emergence and spread of antibiotic-resistant organisms are becoming more and more serious and are a worldwide problem. Recent trends in new antibiotic-resistant organisms include multiple-drug resistant Pseudomonas aeruginosa (MDRP), MDR-Acinetobacter baumannii (MDR-AB) and New Deli metallo beta-lactamase-1 (NDM-1) -producing bacteria. Antibiotic combination therapy is an option to overcome these MDR organisms. A breakpoint checkerboard plate was created to measure antibiotic combination effects at breakpoint concentrations, making it possible to evaluate the synergy of antibiotic combination within 24 hours. In this article, recent topics regarding antibiotic-resistant organisms are briefly reviewed and the directions of antibiotic chemotherapy against these organisms are discussed.

Antibiotics: Misuse Puts You and Others at Risk

MedlinePlus

... those bacteria are said to be antibiotic resistant. Antibiotic resistance is one of the world's most pressing health ... misuse of antibiotics are key factors contributing to antibiotic resistance. The general public, doctors and hospitals all play ...

Comparison of the loads and antibiotic-resistance profiles of Enterococcus species from conventional and organic chicken carcasses in South Korea.

PubMed

Kim, Y-J; Park, J-H; Seo, K-H

2018-01-01

Antibiotic-resistant bacteria in poultry meat are a threat to public health. In this study, we compared the Enterococcus spp. loads and antibiotic-resistance profiles between carcasses of conventionally and organically raised chickens. A total of 144 chicken carcasses (72 conventional and 72 organic) was collected from local retail markets in Seoul, South Korea. Overall, 77.7% (112 of 144; 75% conventional and 80% organic) of chicken carcasses were positive for Enterococcus. The mean loads of Enterococcus spp. were greater in conventional chicken carcasses, at 2.9 ± 0.4 log CFU/mL, than those in organic chicken carcasses, at 1.78 ± 0.3 log CFU/mL (p < 0.05). A total of 104 isolates (52 from conventional and 52 from organic chicken carcasses) was randomly selected for further analysis. The predominant species was Enterococcus faecalis in both conventional and organic chicken carcasses (57.7 and 76.9%, respectively; P > 0.05). Rates of resistance to ciprofloxacin and erythromycin, which are used in veterinary medicine in South Korea, were significantly higher in conventional chicken carcasses than in organic chicken carcasses. However, we found no difference between the rates of resistance to antibiotics such as vancomycin and tigecycline, which were not registered for use in veterinary medicine in South Korea, of Enterococcus isolates from conventional and organic chicken carcasses. In addition, although multidrug resistant isolates were obtained from both types of chicken samples, the prevalence of samples positive for Enterococcus was significantly higher in conventional chicken carcasses than in organic chicken carcasses (P < 0.05). The most common multidrug resistance pattern was erythromycin-tetracycline-rifampicin in conventional chicken carcasses and quinupristin-dalfopristin-tetracycline-rifampicin in organic chicken carcasses. A high level of gentamicin resistance was observed in isolates from not only conventional (5.8%) but also organic chicken (1.9%) carcasses, with no significant difference in rates between them (P > 0.05). Despite this, our results suggest that organic food certification is effective in reducing fecal contamination and the burden of antibiotic-resistant Enterococcus spp. in chicken carcasses. © 2017 Poultry Science Association Inc.

Treatment of acute otitis media - challenges in the era of antibiotic resistance.

PubMed

Dagan, R

2000-12-08

The last decade is characterized by the increase in antibiotic resistance among respiratory bacterial pathogens in the presence of only modest progress in the development of new antibacterial agents to overcome this resistance. A series of recent studies show clearly that the increased resistance among the main AOM pathogens (namely Streptococcus pneumoniae and Haemophilus influenzae) is associated with a dramatic decrease in bacteriologic response to antibiotic treatment, which in turn has an impact on clinical response. Thus, the individual patient is affected by the increasing antibiotic resistance. Moreover, the society as a whole is now also affected because the carriage and spread of antibiotic resistant AOM pathogens is remarkably impacted by antibiotic treatment. New studies show the remarkable ability of antibiotics to rapidly promote nasopharyngeal carriage and spread of antibiotic-resistant AOM pathogens. In these studies, the increase in carriage of antibiotic resistant S. pneumoniae is shown already after 3-4 days from initiation of antibiotic treatment and may last for weeks to months after treatment. Children carrying antibiotic-resistant organisms transmit those organisms to their family and to their day care centers and thus a vicious cycle is created in which increased antibiotic resistance with decreased response leads to increased antibiotic use, which in turn leads to further increase in resistance. New antibiotics are not likely to improve this situation. It is clear that the challenge in the next decade is to prevent AOM rather than to treat it. Efforts to prevent AOM include improved environmental factors, immunization with bacterial and viral vaccines and some creative measures such as prevention of colonization and attachment to epithelium of AOM pathogens. Whether these efforts will prove successful or, even if successful, will only modify the clinical and bacteriologic picture presenting new challenges, only time will tell.

Molecular detection of mutations involved in Helicobacter pylori antibiotic resistance in Algeria.

PubMed

Bachir, Meryem; Allem, Rachida; Benejat, Lucie; Tifrit, Abedelkarim; Medjekane, Meriem; Drici, Amine El-Mokhtar; Megraud, Francis; Douidi, Kara Turki

2018-05-11

In Algeria, there are limited data regarding the pattern of Helicobacter pylori primary antibiotic resistance. The aim of this study was to evaluate the primary resistance of H. pylori to clarithromycin, ciprofloxacin, tetracycline and rifampicin and to determine the molecular mechanisms involved in the resistance. Two hundred and seventy Algerian adults who had never received H. pylori treatment were enrolled in this study. Human biopsies were obtained for culture and antimicrobial susceptibility testing was performed by Etest for clarithromycin, ciprofloxacin, tetracycline and rifampicin. Real-time fluorescence resonance energy transfer (FRET)-PCR was also performed in all cases to assess primary clarithromycin resistance and point mutations involved, real-time PCR was used to detect mutations involved in tetracycline primary resistance and sequencing of the QRDR of gyrA was performed to detect mutations involved in quinolone resistance. No resistance to rifampicin was detected. Resistance to clarithromycin and ciprofloxacin was found in 29.7% and 17.9%, respectively. Results of real-time FRET-PCR showed that A2143G was the most frequent point mutation, A2142C was not found and 42 patients (15.5%) were infected by both resistant and susceptible genotypes. Only two isolates were resistant to tetracycline and exhibited an A926G mutation. Four mutations were found to be responsible for resistance to ciprofloxacin [N87K (44.73%), D91N (23.68%), N87I (18.42%) and D91G (7.89%)]. Local data regarding the primary resistance of H. pylori to clarithromycin, ciprofloxacin, tetracycline and rifampicin and the main genetic mutations involved in the resistance are necessary for a periodic evaluation of antibiotic consumption and new therapeutic strategies in Algeria.

Fate and transport of veterinary antibiotics, antibiotic-resistant bacteria, and antibiotic resistance gene from fields receiving poultry manure during storm events

USDA-ARS?s Scientific Manuscript database

Antimicrobials are used in production agriculture to treat disease and promote animal growth, but the presence of antibiotics in the environment raises concern about widespread antibiotic resistance. This study documents the occurrence and transport of tylosin, tetracycline, enterococci resistant to...

Antibiotic resistance genes in surface water of eutrophic urban lakes are related to heavy metals, antibiotics, lake morphology and anthropic impact.

PubMed

Yang, Yuyi; Xu, Chen; Cao, Xinhua; Lin, Hui; Wang, Jun

2017-08-01

Urban lakes are impacted by heavy human activities and represent potential reservoirs for antibiotic resistance genes. In this study, six urban lakes in Wuhan, central China were selected to analyze the distribution of sulfonamide resistance (sul) genes, tetracycline resistance (tet) genes and quinolone resistance (qnr) genes and their relationship with heavy metals, antibiotics, lake morphology and anthropic impact. sul1 and sul2 were detected in all six lakes and dominated the types of antibiotic resistance genes, which accounted for 86.28-97.79% of the total antibiotic resistance gene abundance. For eight tested tet genes, antibiotic efflux pumps (tetA, tetB, tetC, and tetG) genes were all observed in six lakes and had higher relative abundance than ribosomal protection protein genes (tetM and tetQ). For 4 plasmid mediated quinolone resistance genes, only qnrD is found in all six lakes. The class I integron (intI1) is also found to be a very important media for antibiotic resistance gene propagation in urban lakes. The results of redundancy analysis and variation partitioning analysis showed that antibiotic and co-selection with heavy metals were the major factors driving the propagation of antibiotic resistance genes in six urban lakes. The heavily eutrophic Nanhu Lake and Shahu Lake which located in a high density building area with heavy human activities had the higher relative abundance of total antibiotic resistance genes. Our study could provide a useful reference for antibiotic resistance gene abundance in urban lakes with high anthropic impact.

Antimicrobial resistance: the major contribution of poor governance and corruption to this growing problem.

PubMed

Collignon, Peter; Athukorala, Prema-Chandra; Senanayake, Sanjaya; Khan, Fahad

2015-01-01

To determine how important governmental, social, and economic factors are in driving antibiotic resistance compared to the factors usually considered the main driving factors-antibiotic usage and levels of economic development. A retrospective multivariate analysis of the variation of antibiotic resistance in Europe in terms of human antibiotic usage, private health care expenditure, tertiary education, the level of economic advancement (per capita GDP), and quality of governance (corruption). The model was estimated using a panel data set involving 7 common human bloodstream isolates and covering 28 European countries for the period 1998-2010. Only 28% of the total variation in antibiotic resistance among countries is attributable to variation in antibiotic usage. If time effects are included the explanatory power increases to 33%. However when the control of corruption indicator is included as an additional variable, 63% of the total variation in antibiotic resistance is now explained by the regression. The complete multivariate regression only accomplishes an additional 7% in terms of goodness of fit, indicating that corruption is the main socioeconomic factor that explains antibiotic resistance. The income level of a country appeared to have no effect on resistance rates in the multivariate analysis. The estimated impact of corruption was statistically significant (p< 0.01). The coefficient indicates that an improvement of one unit in the corruption indicator is associated with a reduction in antibiotic resistance by approximately 0.7 units. The estimated coefficient of private health expenditure showed that one unit reduction is associated with a 0.2 unit decrease in antibiotic resistance. These findings support the hypothesis that poor governance and corruption contributes to levels of antibiotic resistance and correlate better than antibiotic usage volumes with resistance rates. We conclude that addressing corruption and improving governance will lead to a reduction in antibiotic resistance.

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

PubMed

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

2015-06-01

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

Prevalence of Antibiotic-Resistant Escherichia coli in Drinking Water Sources in Hangzhou City

PubMed Central

Chen, Zhaojun; Yu, Daojun; He, Songzhe; Ye, Hui; Zhang, Lei; Wen, Yanping; Zhang, Wenhui; Shu, Liping; Chen, Shuchang

2017-01-01

This study investigated the distribution of antibiotic resistant Escherichia coli (E. coli) and examined the possible relationship between water quality parameters and antibiotic resistance from two different drinking water sources (the Qiantang River and the Dongtiao Stream) in Hangzhou city of China. E. coli isolates were tested for their susceptibility to 18 antibiotics. Most of the isolates were resistant to tetracycline (TE), followed by ampicillin (AM), piperacillin (PIP), trimethoprim/sulfamethoxazole (SXT), and chloramphenicol (C). The antibiotic resistance rate of E. coli isolates from two water sources was similar; For E. coli isolates from the Qiantang River, their antibiotic resistance rates decreased from up- to downstream. Seasonally, the dry and wet season had little impact on antibiotic resistance. Spearman's rank correlation revealed significant correlation between resistance to TE and phenicols or ciprofloxacin (CIP), as well as quinolones (ciprofloxacin and levofloxacin) and cephalosporins or gentamicin (GM). Pearson's chi-square tests found certain water parameters such as nutrient concentration were strongly associated with resistance to some of the antibiotics. In addition, tet genes were detected from all 82 TE-resistant E. coli isolates, and most of the isolates (81.87%) contained multiple tet genes, which displayed 14 different combinations. Collectively, this study provided baseline data on antibiotic resistance of drinking water sources in Hangzhou city, which indicates drinking water sources could be the reservoir of antibiotic resistance, potentially presenting a public health risk. PMID:28670309

Prevalence of Antibiotic-Resistant Escherichia coli in Drinking Water Sources in Hangzhou City.

PubMed

Chen, Zhaojun; Yu, Daojun; He, Songzhe; Ye, Hui; Zhang, Lei; Wen, Yanping; Zhang, Wenhui; Shu, Liping; Chen, Shuchang

2017-01-01

This study investigated the distribution of antibiotic resistant Escherichia coli ( E. coli ) and examined the possible relationship between water quality parameters and antibiotic resistance from two different drinking water sources (the Qiantang River and the Dongtiao Stream) in Hangzhou city of China. E. coli isolates were tested for their susceptibility to 18 antibiotics. Most of the isolates were resistant to tetracycline (TE), followed by ampicillin (AM), piperacillin (PIP), trimethoprim/sulfamethoxazole (SXT), and chloramphenicol (C). The antibiotic resistance rate of E. coli isolates from two water sources was similar; For E. coli isolates from the Qiantang River, their antibiotic resistance rates decreased from up- to downstream. Seasonally, the dry and wet season had little impact on antibiotic resistance. Spearman's rank correlation revealed significant correlation between resistance to TE and phenicols or ciprofloxacin (CIP), as well as quinolones (ciprofloxacin and levofloxacin) and cephalosporins or gentamicin (GM). Pearson's chi-square tests found certain water parameters such as nutrient concentration were strongly associated with resistance to some of the antibiotics. In addition, tet genes were detected from all 82 TE-resistant E. coli isolates, and most of the isolates (81.87%) contained multiple tet genes, which displayed 14 different combinations. Collectively, this study provided baseline data on antibiotic resistance of drinking water sources in Hangzhou city, which indicates drinking water sources could be the reservoir of antibiotic resistance, potentially presenting a public health risk.

Strategies to Minimize Antibiotic Resistance

PubMed Central

Lee, Chang-Ro; Cho, Ill Hwan; Jeong, Byeong Chul; Lee, Sang Hee

2013-01-01

Antibiotic resistance can be reduced by using antibiotics prudently based on guidelines of antimicrobial stewardship programs (ASPs) and various data such as pharmacokinetic (PK) and pharmacodynamic (PD) properties of antibiotics, diagnostic testing, antimicrobial susceptibility testing (AST), clinical response, and effects on the microbiota, as well as by new antibiotic developments. The controlled use of antibiotics in food animals is another cornerstone among efforts to reduce antibiotic resistance. All major resistance-control strategies recommend education for patients, children (e.g., through schools and day care), the public, and relevant healthcare professionals (e.g., primary-care physicians, pharmacists, and medical students) regarding unique features of bacterial infections and antibiotics, prudent antibiotic prescribing as a positive construct, and personal hygiene (e.g., handwashing). The problem of antibiotic resistance can be minimized only by concerted efforts of all members of society for ensuring the continued efficiency of antibiotics. PMID:24036486

Antibiotic Adjuvants: Rescuing Antibiotics from Resistance.

PubMed

Wright, Gerard D

2016-11-01

Rooted in the mechanism of action of antibiotics and subject to bacterial evolution, antibiotic resistance is difficult and perhaps impossible to overcome. Nevertheless, strategies can be used to minimize the emergence and impact of resistance. Antibiotic adjuvants offer one such approach. These are compounds that have little or no antibiotic activity themselves but act to block resistance or otherwise enhance antibiotic action. Antibiotic adjuvants are therefore delivered in combination with antibiotics and can be divided into two groups: Class I agents that act on the pathogen, and Class II agents that act on the host. Adjuvants offer a means to both suppress the emergence of resistance and rescue the activity of existing drugs, offering an orthogonal strategy complimentary to new antibiotic discovery VIDEO ABSTRACT. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antimicrobial resistance of Escherichia coli isolated in newly-hatched chickens and effect of amoxicillin treatment during their growth.

PubMed

Jiménez-Belenguer, Ana; Doménech, Eva; Villagrá, Arantxa; Fenollar, Alejandro; Ferrús, Maria Antonia

2016-08-01

The use of antimicrobials in food animals is the major determinant for the propagation of resistant bacteria in the animal reservoir. However, other factors may also play a part, and in particular vertical spread between the generations has been suggested to be an important transmission pathway. The objective of this paper was to determine the resistance patterns of Escherichia coli isolated from newly-hatched chickens as well as to study the antibiotic pressure effect when amoxicillin was administered during their growing period. With this aim, meconium from 22 one-day-old Ross chickens was analysed. In addition, during their growth period, amoxicillin treatments at days 7, 21 and 35 were carried out. Results showed a high number of E. coli-resistant strains were isolated from the treated one-day-old chickens, and were the highest for β-lactams group, followed by quinolone and tetracyclines. After treatment with amoxicillin, the highest percentage of resistances were detected for this antibiotic compared to the others analysed, with significant differences in resistance percentages between control and treated broilers detected in relation to ampicillin, cephalothin, streptomycin, kanamycin, gentamicin, chloramphenicol and tetracycline. Differences in resistances to ciprofloxacin and nalidixic acid between control and treated animals were not observed and there was lack of resistance for amikacin and ceftriaxone. These results suggest the possibility of vertical transmission of resistant strains to newly-hatched chicks from parent flocks, and seem to indicate that the treatment with amoxicillin increased the resistance of E. coli to other antibiotics.

Clusters of antibiotic resistance genes enriched together stay together in swine agriculture

DOE PAGES

Johnson, Timothy A.; Stedtfeld, Robert D.; Wang, Qiong; ...

2016-04-12

Antibiotic resistance is a worldwide health risk, but the influence of animal agriculture on the genetic context and enrichment of individual antibiotic resistance alleles remains unclear. Using quantitative PCR followed by amplicon sequencing, we quantified and sequenced 44 genes related to antibiotic resistance, mobile genetic elements, and bacterial phylogeny in microbiomes from U.S. laboratory swine and from swine farms from three Chinese regions. We identified highly abundant resistance clusters: groups of resistance and mobile genetic element alleles that cooccur. For example, the abundance of genes conferring resistance to six classes of antibiotics together with class 1 integrase and the abundancemore » of IS6100-type transposons in three Chinese regions are directly correlated. These resistance cluster genes likely colocalize in microbial genomes in the farms. Resistance cluster alleles were dramatically enriched (up to 1 to 10% as abundant as 16S rRNA) and indicate that multidrug-resistant bacteria are likely the norm rather than an exception in these communities. This enrichment largely occurred independently of phylogenetic composition; thus, resistance clusters are likely present in many bacterial taxa. Furthermore, resistance clusters contain resistance genes that confer resistance to antibiotics independently of their particular use on the farms. Selection for these clusters is likely due to the use of only a subset of the broad range of chemicals to which the clusters confer resistance. The scale of animal agriculture and its wastes, the enrichment and horizontal gene transfer potential of the clusters, and the vicinity of large human populations suggest that managing this resistance reservoir is important for minimizing human risk.Agricultural antibiotic use results in clusters of cooccurring resistance genes that together confer resistance to multiple antibiotics. The use of a single antibiotic could select for an entire suite of resistance genes if they are genetically linked. No links to bacterial membership were observed for these clusters of resistance genes. These findings urge deeper understanding of colocalization of resistance genes and mobile genetic elements in resistance islands and their distribution throughout antibiotic-exposed microbiomes. In addition, as governments seek to combat the rise in antibiotic resistance, a balance is sought between ensuring proper animal health and welfare and preserving medically important antibiotics for therapeutic use. Metagenomic and genomic monitoring will be critical to determine if resistance genes can be reduced in animal microbiomes, or if these gene clusters will continue to be coselected by antibiotics not deemed medically important for human health but used for growth promotion or by medically important antibiotics used therapeutically.« less

Clusters of antibiotic resistance genes enriched together stay together in swine agriculture

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

Johnson, Timothy A.; Stedtfeld, Robert D.; Wang, Qiong

Antibiotic resistance is a worldwide health risk, but the influence of animal agriculture on the genetic context and enrichment of individual antibiotic resistance alleles remains unclear. Using quantitative PCR followed by amplicon sequencing, we quantified and sequenced 44 genes related to antibiotic resistance, mobile genetic elements, and bacterial phylogeny in microbiomes from U.S. laboratory swine and from swine farms from three Chinese regions. We identified highly abundant resistance clusters: groups of resistance and mobile genetic element alleles that cooccur. For example, the abundance of genes conferring resistance to six classes of antibiotics together with class 1 integrase and the abundancemore » of IS6100-type transposons in three Chinese regions are directly correlated. These resistance cluster genes likely colocalize in microbial genomes in the farms. Resistance cluster alleles were dramatically enriched (up to 1 to 10% as abundant as 16S rRNA) and indicate that multidrug-resistant bacteria are likely the norm rather than an exception in these communities. This enrichment largely occurred independently of phylogenetic composition; thus, resistance clusters are likely present in many bacterial taxa. Furthermore, resistance clusters contain resistance genes that confer resistance to antibiotics independently of their particular use on the farms. Selection for these clusters is likely due to the use of only a subset of the broad range of chemicals to which the clusters confer resistance. The scale of animal agriculture and its wastes, the enrichment and horizontal gene transfer potential of the clusters, and the vicinity of large human populations suggest that managing this resistance reservoir is important for minimizing human risk.Agricultural antibiotic use results in clusters of cooccurring resistance genes that together confer resistance to multiple antibiotics. The use of a single antibiotic could select for an entire suite of resistance genes if they are genetically linked. No links to bacterial membership were observed for these clusters of resistance genes. These findings urge deeper understanding of colocalization of resistance genes and mobile genetic elements in resistance islands and their distribution throughout antibiotic-exposed microbiomes. In addition, as governments seek to combat the rise in antibiotic resistance, a balance is sought between ensuring proper animal health and welfare and preserving medically important antibiotics for therapeutic use. Metagenomic and genomic monitoring will be critical to determine if resistance genes can be reduced in animal microbiomes, or if these gene clusters will continue to be coselected by antibiotics not deemed medically important for human health but used for growth promotion or by medically important antibiotics used therapeutically.« less

Clusters of Antibiotic Resistance Genes Enriched Together Stay Together in Swine Agriculture.

PubMed

Johnson, Timothy A; Stedtfeld, Robert D; Wang, Qiong; Cole, James R; Hashsham, Syed A; Looft, Torey; Zhu, Yong-Guan; Tiedje, James M

2016-04-12

Antibiotic resistance is a worldwide health risk, but the influence of animal agriculture on the genetic context and enrichment of individual antibiotic resistance alleles remains unclear. Using quantitative PCR followed by amplicon sequencing, we quantified and sequenced 44 genes related to antibiotic resistance, mobile genetic elements, and bacterial phylogeny in microbiomes from U.S. laboratory swine and from swine farms from three Chinese regions. We identified highly abundant resistance clusters: groups of resistance and mobile genetic element alleles that cooccur. For example, the abundance of genes conferring resistance to six classes of antibiotics together with class 1 integrase and the abundance of IS6100-type transposons in three Chinese regions are directly correlated. These resistance cluster genes likely colocalize in microbial genomes in the farms. Resistance cluster alleles were dramatically enriched (up to 1 to 10% as abundant as 16S rRNA) and indicate that multidrug-resistant bacteria are likely the norm rather than an exception in these communities. This enrichment largely occurred independently of phylogenetic composition; thus, resistance clusters are likely present in many bacterial taxa. Furthermore, resistance clusters contain resistance genes that confer resistance to antibiotics independently of their particular use on the farms. Selection for these clusters is likely due to the use of only a subset of the broad range of chemicals to which the clusters confer resistance. The scale of animal agriculture and its wastes, the enrichment and horizontal gene transfer potential of the clusters, and the vicinity of large human populations suggest that managing this resistance reservoir is important for minimizing human risk. Agricultural antibiotic use results in clusters of cooccurring resistance genes that together confer resistance to multiple antibiotics. The use of a single antibiotic could select for an entire suite of resistance genes if they are genetically linked. No links to bacterial membership were observed for these clusters of resistance genes. These findings urge deeper understanding of colocalization of resistance genes and mobile genetic elements in resistance islands and their distribution throughout antibiotic-exposed microbiomes. As governments seek to combat the rise in antibiotic resistance, a balance is sought between ensuring proper animal health and welfare and preserving medically important antibiotics for therapeutic use. Metagenomic and genomic monitoring will be critical to determine if resistance genes can be reduced in animal microbiomes, or if these gene clusters will continue to be coselected by antibiotics not deemed medically important for human health but used for growth promotion or by medically important antibiotics used therapeutically. Copyright © 2016 Johnson et al.

Population structure of Salmonella enterica subspecies enterica (subspecies 1)

USDA-ARS?s Scientific Manuscript database

We sequenced and assembled 354 new Salmonella enterica ssp. enterica genomes. These genomes were chosen to maximize genetic diversity, representing at least 100 different serovars and distinct PFGE patterns within these serovars. 119 of the strains were of known antibiotic resistance,...

Multicenter cross-sectional observational study of antibiotic resistance and the genotypes of Propionibacterium acnes isolated from Chinese patients with acne vulgaris.

PubMed

Fan, Yukun; Hao, Fei; Wang, Weizhen; Lu, Yonghong; He, Li; Wang, Gang; Chen, Wenchieh

2016-04-01

Antibiotics are widely applied in management of acne vulgaris, which raises the issue of antibiotic resistance. Due to improper application and supervision of antibiotics, antibiotic resistance has become a serious problem in China. So, the efficacy of antimicrobial therapy in acne is unclear without an objective monitor of antibiotic resistance of Propionibacterium acnes. This cross-sectional, multicenter observational study is aimed at understanding the status of antibiotic resistance in P. acnes, investigating the measures of acne management in China and analyzing the genotypes of antibiotic-resistant strains of P. acnes. Altogether, 312 strains of P. acnes were collected from patients in five medical centers across central China after reviewing the corresponding medical history in detail. The samples underwent antibiotic susceptibility assays by agar dilution method with a total of 11 classes of antibiotics being tested. The antibiotic-resistant strains were screened and further analyzed by investigation of the genotypes regarding 23S rRNA, 16S rRNA and erm(X). The predominant resistance occurred in macrolides and lincomycin with an overall resistance rate of 47.8%. The resistance to tetracyclines was scarce with only two cases identified. The emergence of minimum inhibitory concentration elevation for tetracyclines is associated with its application history (P < 0.005). The genotypes of the reported macrolide-lincosamide-streptogramin B resistance strains were also spotted in Chinese subjects while other resistance determinants may also exist. The tetracyclines have been proved to be vastly susceptible while macrolides and lincomycin face a serious resistance status in China. © 2015 Japanese Dermatological Association.

Investigating the Antibiotic Resistance Problem.

ERIC Educational Resources Information Center

Lawson, Michael; Lawson, Amy L.

1998-01-01

Seeks to give teachers useful information on the extent of the problem of antibiotic-resistant bacteria, mechanisms bacteria use to resist antibiotics, the causes of the emergence of antibiotic-resistant organisms, and practices that can prevent or reverse this trend. Contains 19 references. (DDR)

Relationship between antibiotic- and disinfectant-resistance profiles in bacteria harvested from tap water.

PubMed

Khan, Sadia; Beattie, Tara K; Knapp, Charles W

2016-06-01

Chlorination is commonly used to control levels of bacteria in drinking water; however, viable bacteria may remain due to chlorine resistance. What is concerning is that surviving bacteria, due to co-selection factors, may also have increased resistance to common antibiotics. This would pose a public health risk as it could link resistant bacteria in the natural environment to human population. Here, we investigated the relationship between chlorine- and antibiotic-resistances by harvesting 148 surviving bacteria from chlorinated drinking-water systems and compared their susceptibilities against chlorine disinfectants and antibiotics. Twenty-two genera were isolated, including members of Paenibacillus, Burkholderia, Escherichia, Sphingomonas and Dermacoccus species. Weak (but significant) correlations were found between chlorine-tolerance and minimum inhibitory concentrations against the antibiotics tetracycline, sulfamethoxazole and amoxicillin, but not against ciprofloxacin; this suggest that chlorine-tolerant bacteria are more likely to also be antibiotic resistant. Further, antibiotic-resistant bacteria survived longer than antibiotic-sensitive organisms when exposed to free chlorine in a contact-time assay; however, there were little differences in susceptibility when exposed to monochloramine. Irrespective of antibiotic-resistance, spore-forming bacteria had higher tolerance against disinfection compounds. The presence of chlorine-resistant bacteria surviving in drinking-water systems may carry additional risk of antibiotic resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterisation of antibiotic prescriptions for acute respiratory tract infections in Danish general practice: a retrospective registry based cohort study.

PubMed

Aabenhus, Rune; Hansen, Malene Plejdrup; Saust, Laura Trolle; Bjerrum, Lars

2017-05-19

Inappropriate use of antibiotics is contributing to the increasing rates of antimicrobial resistance. Several Danish guidelines on antibiotic prescribing for acute respiratory tract infections in general practice have been issued to promote rational prescribing of antibiotics, however it is unclear if these recommendations are followed. We aimed to characterise the pattern of antibiotic prescriptions for patients diagnosed with acute respiratory tract infections, by means of electronic prescriptions, labeled with clinical indications, from Danish general practice. Acute respiratory tract infections accounted for 456,532 antibiotic prescriptions issued between July 2012 and June 2013. Pneumonia was the most common indication with 178,354 prescriptions (39%), followed by acute tonsillitis (21%) and acute otitis media (19%). In total, penicillin V accounted for 58% of all prescriptions, followed by macrolides (18%) and amoxicillin (15%). The use of second-line agents increased with age for all indications, and comprised more than 40% of the prescriptions in patients aged >75 years. Women were more often prescribed antibiotics regardless of clinical indication. This is the first Danish study to characterise antibiotic prescription patterns for acute respiratory tract infections by data linkage of clinical indications. The findings confirm that penicillin V is the most commonly prescribed antibiotic agent for treatment of patients with an acute respiratory tract infection in Danish general practice. However, second-line agents like macrolides and amoxicillin with or without clavulanic acid are overused. Strategies to improve the quality of antibiotic prescribing especially for pneumonia, acute otitis media and acute rhinosinusitis are warranted. TRACKING THE OVERUSE OF ANTIBIOTICS: Better adherence to guidelines for prescribing antibiotics for different respiratory tract infections are warranted in Danish general practice. The over-use of antibiotics, particularly so-called 'second-line' agents such as amoxicillin, increases resistance and may lead to a potentially catastrophic scenario where antibiotics are no longer effective. Exactly how widespread the over-use of antibiotics is for different infections, however, is not clear. Rune Aabenhus at the University of Copenhagen and co-workers analyzed primary care data regarding antibiotic prescriptions for acute respiratory tract infections including pneumonia and ear infections in Denmark. They found that penicillin V-the current recommended first-line drug in Scandinavian countries-accounted for 58 per cent of prescriptions, a figure which should be improved. Amoxicillin and macrolides were over-prescribed, particularly in elderly patients. The team also call for further analysis of prescriptions given by out-of-hours clinics.

Antibiotic resistance shaping multi-level population biology of bacteria

PubMed Central

Baquero, Fernando; Tedim, Ana P.; Coque, Teresa M.

2013-01-01

Antibiotics have natural functions, mostly involving cell-to-cell signaling networks. The anthropogenic production of antibiotics, and its release in the microbiosphere results in a disturbance of these networks, antibiotic resistance tending to preserve its integrity. The cost of such adaptation is the emergence and dissemination of antibiotic resistance genes, and of all genetic and cellular vehicles in which these genes are located. Selection of the combinations of the different evolutionary units (genes, integrons, transposons, plasmids, cells, communities and microbiomes, hosts) is highly asymmetrical. Each unit of selection is a self-interested entity, exploiting the higher hierarchical unit for its own benefit, but in doing so the higher hierarchical unit might acquire critical traits for its spread because of the exploitation of the lower hierarchical unit. This interactive trade-off shapes the population biology of antibiotic resistance, a composed-complex array of the independent “population biologies.” Antibiotics modify the abundance and the interactive field of each of these units. Antibiotics increase the number and evolvability of “clinical” antibiotic resistance genes, but probably also many other genes with different primary functions but with a resistance phenotype present in the environmental resistome. Antibiotics influence the abundance, modularity, and spread of integrons, transposons, and plasmids, mostly acting on structures present before the antibiotic era. Antibiotics enrich particular bacterial lineages and clones and contribute to local clonalization processes. Antibiotics amplify particular genetic exchange communities sharing antibiotic resistance genes and platforms within microbiomes. In particular human or animal hosts, the microbiomic composition might facilitate the interactions between evolutionary units involved in antibiotic resistance. The understanding of antibiotic resistance implies expanding our knowledge on multi-level population biology of bacteria. PMID:23508522

Antibiotic resistance shaping multi-level population biology of bacteria.

PubMed

Baquero, Fernando; Tedim, Ana P; Coque, Teresa M

2013-01-01

Antibiotics have natural functions, mostly involving cell-to-cell signaling networks. The anthropogenic production of antibiotics, and its release in the microbiosphere results in a disturbance of these networks, antibiotic resistance tending to preserve its integrity. The cost of such adaptation is the emergence and dissemination of antibiotic resistance genes, and of all genetic and cellular vehicles in which these genes are located. Selection of the combinations of the different evolutionary units (genes, integrons, transposons, plasmids, cells, communities and microbiomes, hosts) is highly asymmetrical. Each unit of selection is a self-interested entity, exploiting the higher hierarchical unit for its own benefit, but in doing so the higher hierarchical unit might acquire critical traits for its spread because of the exploitation of the lower hierarchical unit. This interactive trade-off shapes the population biology of antibiotic resistance, a composed-complex array of the independent "population biologies." Antibiotics modify the abundance and the interactive field of each of these units. Antibiotics increase the number and evolvability of "clinical" antibiotic resistance genes, but probably also many other genes with different primary functions but with a resistance phenotype present in the environmental resistome. Antibiotics influence the abundance, modularity, and spread of integrons, transposons, and plasmids, mostly acting on structures present before the antibiotic era. Antibiotics enrich particular bacterial lineages and clones and contribute to local clonalization processes. Antibiotics amplify particular genetic exchange communities sharing antibiotic resistance genes and platforms within microbiomes. In particular human or animal hosts, the microbiomic composition might facilitate the interactions between evolutionary units involved in antibiotic resistance. The understanding of antibiotic resistance implies expanding our knowledge on multi-level population biology of bacteria.

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

PubMed

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

2010-01-01

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

Evaluation of antibiotic resistance analysis and ribotyping for identification of faecal pollution sources in an urban watershed.

PubMed

Moore, D F; Harwood, V J; Ferguson, D M; Lukasik, J; Hannah, P; Getrich, M; Brownell, M

2005-01-01

The accuracy of ribotyping and antibiotic resistance analysis (ARA) for prediction of sources of faecal bacterial pollution in an urban southern California watershed was determined using blinded proficiency samples. Antibiotic resistance patterns and HindIII ribotypes of Escherichia coli (n = 997), and antibiotic resistance patterns of Enterococcus spp. (n = 3657) were used to construct libraries from sewage samples and from faeces of seagulls, dogs, cats, horses and humans within the watershed. The three libraries were analysed to determine the accuracy of host source prediction. The internal accuracy of the libraries (average rate of correct classification, ARCC) with six source categories was 44% for E. coli ARA, 69% for E. coli ribotyping and 48% for Enterococcus ARA. Each library's predictive ability towards isolates that were not part of the library was determined using a blinded proficiency panel of 97 E. coli and 99 Enterococcus isolates. Twenty-eight per cent (by ARA) and 27% (by ribotyping) of the E. coli proficiency isolates were assigned to the correct source category. Sixteen per cent were assigned to the same source category by both methods, and 6% were assigned to the correct category. Addition of 2480 E. coli isolates to the ARA library did not improve the ARCC or proficiency accuracy. In contrast, 45% of Enterococcus proficiency isolates were correctly identified by ARA. None of the methods performed well enough on the proficiency panel to be judged ready for application to environmental samples. Most microbial source tracking (MST) studies published have demonstrated library accuracy solely by the internal ARCC measurement. Low rates of correct classification for E. coli proficiency isolates compared with the ARCCs of the libraries indicate that testing of bacteria from samples that are not represented in the library, such as blinded proficiency samples, is necessary to accurately measure predictive ability. The library-based MST methods used in this study may not be suited for determination of the source(s) of faecal pollution in large, urban watersheds.

Research activities to improve the utilization of antibiotics in Africa.

PubMed

Massele, Amos; Tiroyakgosi, Celda; Matome, Matshediso; Desta, Abayneh; Muller, Arno; Paramadhas, Bene D Anand; Malone, Brighid; Kurusa, Gobuiwang; Didimalang, Thatayaone; Moyo, Mosana; Godman, Brian

2017-02-01

There is a need to improve the rational use of antibiotics across continents including Africa. This has resulted in initiatives in Botswana including treatment guidelines and the instigation of Antibiotic Stewardship Programs (ASPs). The next steps involve a greater understanding of current antibiotic utilization and resistance patterns (AMR). This resulted in a 2-day meeting involving key stakeholders principally from Botswana to discuss key issues including AMR rates as well as ASPs in both the public and private sectors. Following this, the findings will be used to plan future studies across Africa including point prevalence studies. The findings will be presented in July 2016 at the next Medicines Utilization Research in Africa meeting will ideally serve as a basis for planning future pertinent interventional studies to enhance the rational use of antibiotics in Botswana and wider.

Antibiotic Resistance in Aeromonas Upstream and Downstream of a Water Resource Recovery Facility

PubMed Central

Henderson, Samantha K.; Askew, Maegan L.; Risenhoover, Hollie G.; McAndrews, Chrystle R.; Kennedy, S. Dawn; Paine, C. Sue

2014-01-01

Aeromonas strains isolated from sediments upstream and downstream of a water resource recovery facility (WRRF) over a two-year time period were tested for susceptibility to thirteen antibiotics. Incidence of resistance to antibiotics, antibiotic resistance phenotypes, and diversity (based on resistance phenotypes) were compared in the two populations. At the beginning of the study, the upstream and downstream Aeromonas populations were different for incidence of antibiotic resistance (p < 0.01), resistance phenotypes (p < 0.005), and diversity. However, these differences declined over time and were not significant at the end of the study. These results (1) indicate that antibiotic resistance in Aeromonas in stream sediments fluctuates considerably over time and (2) suggest that WRRF effluent does not, when examined over the long term, affect antibiotic resistance in Aeromonas in downstream sediment. PMID:25327024

Incidence of multidrug-resistant, extensively drug-resistant and pan-drug-resistant bacteria in children hospitalized at Dr. Hasan Sadikin general hospital Bandung Indonesia

NASA Astrophysics Data System (ADS)

Adrizain, R.; Suryaningrat, F.; Alam, A.; Setiabudi, D.

2018-03-01

Antibiotic resistance has become a global issue, with 700,000 deaths attributable to multidrug-resistance (MDR) occurring each year. Centers for Disease Control and Prevention (CDC) show rapidly increasing rates of infection due to antibiotic-resistant bacteria. The aim of the study isto describe the incidence of MDR, extensively drug-resistant (XDR) and pan drug-resistant (PDR) in Enterococcus spp., Staphylococcus aureus, K. pneumonia, Acinetobacter baumanii, P. aeruginosin, and Enterobacter spp. (ESKAPE) pathogens in children admitted to Dr. Hasan Sadikin Hospital. All pediatric patients having blood culture drawn from January 2015 to December 2016 were retrospectively studied. Data include the number of drawn blood culture, number of positive results, type of bacteria, sensitivity pattern. International standard definitions for acquired resistance by ECDC and CDC was used as definitions for MDR, XDR and PDR bacteria. From January 2015 to December 2016, 299 from 2.542 (11.7%) blood culture was positive, with Staphylococcus aureus, Enterococcus spp., Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter spp., respectively 5, 6, 24, 5, 20 with total 60 (20%). The MDR and XDR pathogen found were 47 and 13 patients, respectively.

Resistance to antibiotics in the normal flora of animals.

PubMed

Sørum, H; Sunde, M

2001-01-01

The normal bacterial flora contains antibiotic resistance genes to various degrees, even in individuals with no history of exposure to commercially prepared antibiotics. Several factors seem to increase the number of antibiotic-resistant bacteria in feces. One important factor is the exposure of the intestinal flora to antibacterial drugs. Antibiotics used as feed additives seem to play an important role in the development of antibiotic resistance in normal flora bacteria. The use of avoparcin as a feed additive has demonstrated that an antibiotic considered "safe" is responsible for increased levels of antibiotic resistance in the normal flora enterococci of animals fed with avoparcin and possibly in humans consuming products from these animals. However, other factors like stress from temperature, crowding, and management also seem to contribute to the occurrence of antibiotic resistance in normal flora bacteria. The normal flora of animals has been studied with respect to the development of antibiotic resistance over four decades, but there are few studies with the intestinal flora as the main focus. The results of earlier studies are valuable when focused against the recent understanding of mobile genetics responsible for bacterial antibiotic resistance. New studies should be undertaken to assess whether the development of antibiotic resistance in the normal flora is directly linked to the dramatic increase in antibiotic resistance of bacterial pathogens. Bacteria of the normal flora, often disregarded scientifically, should be studied with the intention of using them as active protection against infectious diseases and thereby contributing to the overall reduction of use of antibioties in both animals and humans.

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.

Genetic Mechanisms of Antibiotic Resistance and the Role of Antibiotic Adjuvants.

PubMed

Pontes, Daniela Santos; de Araujo, Rodrigo Santos Aquino; Dantas, Natalina; Scotti, Luciana; Scotti, Marcus Tullius; de Moura, Ricardo Olimpio; Mendonca-Junior, Francisco Jaime Bezerra

2018-01-01

The ever increasing number of multidrug-resistant microorganism pathogens has become a great and global public health threat. Antibiotic mechanisms of action and the opposing mechanisms of resistance are intimately associated, but comprehension of the biochemical and molecular functions of such drugs is not a simple exercise. Both the environment, and genetic settings contribute to alterations in phenotypic resistance (natural bacterial evolution), and make it difficult to control the emergence and impacts of antibiotic resistance. Under such circumstances, comprehension of how bacteria develop and/or acquire antibiotic resistance genes (ARG) has a critical role in developing propositions to fight against these superbugs, and to search for new drugs. In this review, we present and discuss both general information and examples of common genetic and molecular mechanisms related to antibiotic resistance, as well as how the expression and interactions of ARGs are important to drug resistance. At the same time, we focus on the recent achievements in the search for antibiotic adjuvants, which help combat antibiotic resistance through deactivation of bacterial mechanisms of action such as β-lactamases. Recent advances involving the use of anti-resistance drugs such as: efflux pump inhibitors; anti-virulence drugs; drugs against quorum sensing; and against type II/III secretion systems are revealed. Such antibiotic adjuvants (as explored herein) collaborate against the problems of antibiotic resistance, and may restore or prolong the therapeutic activity of known antibiotics. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Control of antibiotic resistance in China must not be delayed: The current state of resistance and policy suggestions for the government, medical facilities, and patients.

PubMed

Tang, Qi; Song, Peipei; Li, Jiajia; Kong, Fanlei; Sun, Long; Xu, Lingzhong

2016-02-01

Antibiotics are medicines used to prevent and treat bacterial infections. Antibiotic resistance occurs when bacteria change in response to the use of these medicines. Antibiotic resistance is rising to dangerously high levels in all parts of the world, leading to higher medical costs, prolonged hospital stays, and increased mortality. In the European Union alone, drug-resistant bacteria are estimated to cause 25,000 deaths and cost more than US$1.5 billion every year in healthcare expenses and productivity losses. The problems of antibiotic misuse and antibiotic resistance are quite serious in China. In 2015, results of a study by the State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences indicated that the total antibiotic usage in China in 2013 was approximately 162,000 tons, including human use (48%) and use in animals (52%). This amount accounted for about half of the antibiotic usage worldwide. The per-capita use of antibiotics in China is more than 5 times that in Europe and the United States. These data mean that China is one of the world's leading countries with serious problems in terms of antibiotic misuse and antibiotic resistance. The current article analyzes the current state and harms of antibiotic misuse and causes of antibiotic resistance in China. The Government needs to pay close attention to the issue of antibiotic resistance in China and formulate a strategy at the national level. Thus, the following suggestions are offered: i) The Chinese Government should implement policies that promote antibiotic research and development; ii) Medical facilities in China should create multidisciplinary teams (MDTs) and encourage early action by MDTs to control the spread of multi-drug-resistant bacteria (MDRB); iii) An intervention in the form of health education should target patients and accompanying family members (AFM) in China. In other words, antibiotic resistance is not a personal problem but an urgent public health problem. Without urgent action, China is heading for a post-antibiotic era in which common infections and minor injuries can once again kill. Therefore, the aforementioned proposals have been offered with the hope that policy suggestions help to limit the phenomenon of antibiotic misuse and antibiotic resistance in China.

Water Disinfection Byproducts Induce Antibiotic Resistance-Role of Environmental Pollutants in Resistance Phenomena.

PubMed

Li, Dan; Zeng, Siyu; He, Miao; Gu, April Z

2016-03-15

The spread of antibiotic resistance represents a global threat to public health, and has been traditionally attributed to extensive antibiotic uses in clinical and agricultural applications. As a result, researchers have mostly focused on clinically relevant high-level resistance enriched by antibiotics above the minimal inhibitory concentrations (MICs). Here, we report that two common water disinfection byproducts (chlorite and iodoacetic acid) had antibiotic-like effects that led to the evolution of resistant E. coli strains under both high (near MICs) and low (sub-MIC) exposure concentrations. The subinhibitory concentrations of DBPs selected strains with resistance higher than those evolved under above-MIC exposure concentrations. In addition, whole-genome analysis revealed distinct mutations in small sets of genes known to be involved in multiple drug and drug-specific resistance, as well as in genes not yet identified to play role in antibiotic resistance. The number and identities of genetic mutations were distinct for either the high versus low sub-MIC concentrations exposure scenarios. This study provides evidence and mechanistic insight into the sub-MIC selection of antibiotic resistance by antibiotic-like environmental pollutants such as disinfection byproducts in water, which may be important contributors to the spread of global antibiotic resistance. The results from this study open an intriguing and profound question on the roles of large amount and various environmental contaminants play in selecting and spreading the antibiotics resistance in the environment.

Bacterial Cheating Limits the Evolution of Antibiotic Resistance

NASA Astrophysics Data System (ADS)

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

2012-02-01

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

Comparison of Epidemiological and Antibiotic Susceptibility Pattern of Metallo-Beta-Lactamase-Positive and Metallo-Beta-Lactamase-Negative Strains of Pseudomonas Aeruginosa

PubMed Central

Ranjan, Shikha; Banashankari, GS; Babu, PR Sreenivasa

2014-01-01

Background: The infections caused by metallo-beta-lactamases (MBLs) producing Pseudomonas aeruginosa are associated with higher rates of mortality, morbidity, and overall healthcare costs compared to non-MBL P. aeruginosa infections. Purpose: To compare the epidemiologic factors and antibiograms of MBL-positive and MBL-negative P. aeruginosa isolates in a tertiary care hospital. Methods: In an observational study, from January 2011 to December 2012, all non-duplicate P. aeruginosa isolates were subjected to an antimicrobial sensitivity test against 10 antibiotics of five different classes. All P. aeruginosa strains showing resistance to at least one of the carbapenems were subjected to the MBL-E test. Epidemiological features and antibiograms of MBL-positive and MBL-negative strains were compared and statistically analyzed. Results: Out of 350 isolates (total sample = 5330) of P. aeruginosa, MBL was detected in 58 isolates by the E-test, resulting in a prevalence of 16.57%. Resistance to most of the antibiotics was significantly higher in the MBL-positive strains with 100% resistance to ciprofloxacin, tobramycin, and meropenem, followed by imipenem (93.10%) and gentamicin (89.66%). The prevalence of multidrug-resistant and pandrug-resistant strains was significantly higher among the MBL group as compared to that in the non-MBL group ((55.17 vs. 7.88% (P < 0.0001) and 8.62 vs. 0.68% (P = 0.0006)), respectively. Conclusions: MBL-positive P. aeruginosa strains showed very high resistance to various antibiotics, as compared to the non-MBL strains. Increasing prevalence of MBL-producing isolates in hospital settings makes it important to perform routine detection of MBL-positive P. aeruginosa strains by in vitro testing before antibiotic use, for the purposes of infection prevention, and control, and for minimizing the adverse outcomes of infections with MBL-producing strains. PMID:25328336

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

PubMed

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

2018-06-02

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

Antibiotic resistance ofKlebsiella pneumoniae through β-arrestin recruitment-induced β-lactamase signaling pathway.

PubMed

Wei, Jiang; Wenjie, Yang; Ping, Liu; Na, Wang; Haixia, Ren; Xuequn, Zhao

2018-03-01

Overuse and misuse of antibiotics leads to rapid evolution of antibiotic-resistant bacteria and antibiotic resistance genes. Klebsiella pneumoniae has become the most common pathogenic bacterium accountable for nosocomial infections due to its high virulence factor and general occurrence of resistance to most antibiotics. The β-lactamase signaling pathway has been suggested to be involved in antibiotic resistance against β-lactams in Klebsiella pneumoniae . In the present study, the molecular mechanism of the antibiotic resistance of Klebsiella pneumoniae was investigated and the results indicated involvement of the β-arrestin recruitment-induced β-lactamase signaling pathway. Antimicrobial susceptibility of Klebsiella pneumoniae was assessed using automated systems and extended-spectrum β-lactamase (ESBL) and β-arrestin expression levels in Klebsiella pneumoniae were analyzed by reverse-transcription quantitative PCR. β-lactam resistance in Klebsiella pneumoniae was determined using β-lactam agar screening plates. The results demonstrated that β-arrestin recruitment was increased in Klebsiella pneumoniae with antibiotic resistance (AR- K.P .) compared with that in the native Klebsiella pneumoniae strain (NB- K.P .). Increased production of ESBL was observed in AR- K.P . after treatment with the β-lactam penicillin. Of note, inhibition of β-arrestin recruitment significantly suppressed ESBL expression in AR- K.P . and in addition, genes encoding β-arrestin and ESBL were upregulated in Klebsiella pneumoniae . Restoration of endogenous β-arrestin markedly increased antibiotic resistance of Klebsiella pneumoniae to β-lactam. Knockdown of endogenous β-arrestin downregulated antibiotic resistance genes and promoted the inhibitory effects of β-lactam antibiotic treatment on Klebsiella pneumoniae growth. In conclusion, the present study identified that β-arrestin recruitment was associated with growth and resistance to β-lactams, which suggested that β-arrestin regulating ESBL expression may be a potential target for addressing antibiotic resistance to β-lactams in Klebsiella pneumoniae .

Containing antibiotic resistance: decreased antibiotic-resistant coliform urinary tract infections with reduction in antibiotic prescribing by general practices

PubMed Central

Butler, Chris C; Dunstan, Frank; Heginbothom, Margaret; Mason, Brendan; Roberts, Zoë; Hillier, Sharon; Howe, Robin; Palmer, Stephen; Howard, Anthony

2007-01-01

Background GPs are urged to prescribe antibiotics less frequently, despite lack of evidence linking reduced antibiotic prescribing with reductions in resistance at a local level. Aim To investigate associations between changes in antibiotic dispensing and changes in antibiotic resistance at general-practice level. Design of study Seven-year study of dispensed antibiotics and antibiotic resistance in coliform isolates from urine samples routinely submitted from general practice. Setting General practices in Wales. Method Multilevel modelling of trends in resistance to ampicillin and trimethoprim, and changes in practice total antibiotic dispensing and amoxicillin and trimethoprim dispensing. Results The primary analysis included data on 164 225 coliform isolates from urine samples submitted from 240 general practices over the 7-year study period. These practices served a population of 1.7 million patients. The quartile of practices that had the greatest decrease in total antibiotic dispensing demonstrated a 5.2% reduction in ampicillin resistance over the 7-year period with changes of 0.4%, 2.4%, and −0.3% in the other three quartiles. There was a statistically significant overall decrease in ampicillin resistance of 1.03% (95% confidence interval [CI] = 0.37 to 1.67%) per decrease of 50 amoxicillin items dispensed per 1000 patients per annum. There were also significant reductions in trimethoprim resistance in the two quartiles of practices that reduced total antibiotic dispensing most compared with those that reduced it least, with an overall decrease in trimethoprim resistance of 1.08% (95% CI = 0.065 to 2.10%) per decrease of 20 trimethoprim items dispensed per 1000 patients per annum. Main findings were confirmed by secondary analyses of 256 370 isolates from 527 practices that contributed data at some point during the study period. Conclusion Reducing antibiotic dispensing at general-practice level is associated with reduced local antibiotic resistance. These findings should further encourage clinicians and patients to use antibiotics conservatively. PMID:17925135

Patient perceptions of antibiotic use and resistance at a single university dermatology clinic.

PubMed

Goettsche, Lainee S; Weig, Emily A; Chung, Jina; Hoff, Brian M; Ince, Dilek; Wanat, Karolyn A

2018-05-21

Antibiotic resistance is an important problem that requires continued patient education and important prescribing stewardship. Dermatologists prescribe the most antibiotics per provider in comparison to other specialties and have an important role to play in the campaign of mindful prescribing. Data on the dermatology patients' knowledge and perception regarding antibiotic resistance is lacking and could play a role in providers' continuation of medications. We conducted a single institution survey of 512 dermatology clinic patients to understand patient's knowledge and potential gaps. Overall, our results demonstrated an overall higher level of knowledge than expected, there were still several knowledge gaps identified. Ninety-one percent of respondents were aware of the term 'antibiotic resistance'. However, 65% of participants believed that a short course of antibiotics could not cause resistance. While our patients have awareness of antibiotic resistance, it is imperative to continue to assess patients' knowledge about antibiotic resistance and provide education whenever possible in order to continue to practice antibiotic stewardship.

Origins and Evolution of Antibiotic Resistance

PubMed Central

Davies, Julian; Davies, Dorothy

2010-01-01

Summary: Antibiotics have always been considered one of the wonder discoveries of the 20th century. This is true, but the real wonder is the rise of antibiotic resistance in hospitals, communities, and the environment concomitant with their use. The extraordinary genetic capacities of microbes have benefitted from man's overuse of antibiotics to exploit every source of resistance genes and every means of horizontal gene transmission to develop multiple mechanisms of resistance for each and every antibiotic introduced into practice clinically, agriculturally, or otherwise. This review presents the salient aspects of antibiotic resistance development over the past half-century, with the oft-restated conclusion that it is time to act. To achieve complete restitution of therapeutic applications of antibiotics, there is a need for more information on the role of environmental microbiomes in the rise of antibiotic resistance. In particular, creative approaches to the discovery of novel antibiotics and their expedited and controlled introduction to therapy are obligatory. PMID:20805405

A Common Platform for Antibiotic Dereplication and Adjuvant Discovery.

PubMed

Cox, Georgina; Sieron, Arthur; King, Andrew M; De Pascale, Gianfranco; Pawlowski, Andrew C; Koteva, Kalinka; Wright, Gerard D

2017-01-19

Solving the antibiotic resistance crisis requires the discovery of new antimicrobial drugs and the preservation of existing ones. The discovery of inhibitors of antibiotic resistance, antibiotic adjuvants, is a proven example of the latter. A major difficulty in identifying new antibiotics is the frequent rediscovery of known compounds, necessitating laborious "dereplication" to identify novel chemical entities. We have developed an antibiotic resistance platform (ARP) that can be used for both the identification of antibiotic adjuvants and for antibiotic dereplication. The ARP is a cell-based array of mechanistically distinct individual resistance elements in an identical genetic background. In dereplication mode, we demonstrate the rapid identification, and thus discrimination, of common antibiotics. In adjuvant discovery mode, we show that the ARP can be harnessed in screens to identify inhibitors of resistance. The ARP is therefore a powerful tool that has broad application in confronting the resistance crisis. Copyright © 2017 Elsevier Ltd. All rights reserved.

The antibiotic resistome: gene flow in environments, animals and human beings.

PubMed

Hu, Yongfei; Gao, George F; Zhu, Baoli

2017-06-01

The antibiotic resistance is natural in bacteria and predates the human use of antibiotics. Numerous antibiotic resistance genes (ARGs) have been discovered to confer resistance to a wide range of antibiotics. The ARGs in natural environments are highly integrated and tightly regulated in specific bacterial metabolic networks. However, the antibiotic selection pressure conferred by the use of antibiotics in both human medicine and agriculture practice leads to a significant increase of antibiotic resistance and a steady accumulation of ARGs in bacteria. In this review, we summarized, with an emphasis on an ecological point of view, the important research progress regarding the collective ARGs (antibiotic resistome) in bacterial communities of natural environments, human and animals, i.e., in the one health settings.We propose that the resistance gene flow in nature is "from the natural environments" and "to the natural environments"; human and animals, as intermediate recipients and disseminators, contribute greatly to such a resistance gene "circulation."

Rationalizing antibiotic use to limit antibiotic resistance in India+

PubMed Central

2011-01-01

Antibiotic resistance, a global concern, is particularly pressing in developing nations, including India, where the burden of infectious disease is high and healthcare spending is low. The Global Antibiotic Resistance Partnership (GARP) was established to develop actionable policy recommendations specifically relevant to low- and middle-income countries where suboptimal access to antibiotics - not a major concern in high-income countries - is possibly as severe a problem as is the spread of resistant organisms. This report summarizes the situation as it is known regarding antibiotic use and growing resistance in India and recommends short and long term actions. Recommendations aim at (i) reducing the need for antibiotics; (ii) lowering resistance-enhancing drug pressure through improved antibiotic targeting, and (iii) eliminating antibiotic use for growth promotion in agriculture. The highest priority needs to be given to (i) national surveillance of antibiotic resistance and antibiotic use - better information to underpin decisions on standard treatment guidelines, education and other actions, as well as to monitor changes over time; (ii) increasing the use of diagnostic tests, which necessitates behavioural changes and improvements in microbiology laboratory capacity; (iii) setting up and/or strengthening infection control committees in hospitals; and (iv) restricting the use of antibiotics for non-therapeutic uses in agriculture. These interventions should help to reduce the spread of antibiotic resistance, improve public health directly, benefit the populace and reduce pressure on the healthcare system. Finally, increasing the types and coverage of childhood vaccines offered by the government would reduce the disease burden enormously and spare antibiotics. PMID:21985810

Lessons from the Environmental Antibiotic Resistome.

PubMed

Surette, Matthew D; Wright, Gerard D

2017-09-08

Antibiotic resistance is a global public health issue of growing proportions. All antibiotics are susceptible to resistance. The evidence is now clear that the environment is the single largest source and reservoir of resistance. Soil, aquatic, atmospheric, animal-associated, and built ecosystems are home to microbes that harbor antibiotic resistance elements and the means to mobilize them. The diversity and abundance of resistance in the environment is consistent with the ancient origins of antibiotics and a variety of studies support a long natural history of associated resistance. The implications are clear: Understanding the evolution of resistance in the environment, its diversity, and mechanisms is essential to the management of our existing and future antibiotic resources.

Carriage of antibiotic-resistant enteric bacteria varies among sites in Galapagos reptiles.

PubMed

Wheeler, Emily; Hong, Pei-Ying; Bedon, Lenin Cruz; Mackie, Roderick I

2012-01-01

Increased overlap between humans and wildlife populations has increased the risk for novel disease emergence. Detecting contacts with a high risk for transmission of pathogens requires the identification of dependable measures of microbial exchange. We evaluated antibiotic resistance as a molecular marker for the intensity of human-wildlife microbial connectivity in the Galápagos Islands. We isolated Escherichia coli and Salmonella enterica from the feces of land iguanas (Conolophus sp.), marine iguanas (Amblyrhynchus cristatus), giant tortoises (Geochelone nigra), and seawater, and tested these bacteria with the use of the disk diffusion method for resistance to 10 antibiotics. Antibiotic-resistant bacteria were found in reptile feces from two tourism sites (Isla Plaza Sur and La Galapaguera on Isla San Cristóbal) and from seawater close to a public use beach near Puerto Baquerizo Moreno on Isla San Cristóbal. No resistance was detected at two protected beaches on more isolated islands (El Miedo on Isla Santa Fe and Cape Douglas on Isla Fernandina) and at a coastal tourism site (La Lobería on Isla San Cristóbal). Eighteen E. coli isolates from three locations, all sites relatively proximate to a port town, were resistant to ampicillin, doxycycline, tetracycline, and trimethoprin/sulfamethoxazole. In contrast, only five S. enterica isolates showed a mild decrease in susceptibility to doxycycline and tetracycline from these same sites (i.e., an intermediate resistance phenotype), but no clinical resistance was detected in this bacterial species. These findings suggest that reptiles living in closer proximity to humans potentially have higher exposure to bacteria of human origin; however, it is not clear from this study to what extent this potential exposure translates to ongoing exchange of bacterial strains or genetic traits. Resistance patterns and bacterial exchange in this system warrant further investigation to understand better how human associations influence disease risk in endemic Galápagos wildlife.

The role of biofilms as environmental reservoirs of antibiotic resistance

PubMed Central

Balcázar, José L.; Subirats, Jéssica; Borrego, Carles M.

2015-01-01

Antibiotic resistance has become a significant and growing threat to public and environmental health. To face this problem both at local and global scales, a better understanding of the sources and mechanisms that contribute to the emergence and spread of antibiotic resistance is required. Recent studies demonstrate that aquatic ecosystems are reservoirs of resistant bacteria and antibiotic resistance genes as well as potential conduits for their transmission to human pathogens. Despite the wealth of information about antibiotic pollution and its effect on the aquatic microbial resistome, the contribution of environmental biofilms to the acquisition and spread of antibiotic resistance has not been fully explored in aquatic systems. Biofilms are structured multicellular communities embedded in a self-produced extracellular matrix that acts as a barrier to antibiotic diffusion. High population densities and proximity of cells in biofilms also increases the chances for genetic exchange among bacterial species converting biofilms in hot spots of antibiotic resistance. This review focuses on the potential effect of antibiotic pollution on biofilm microbial communities, with special emphasis on ecological and evolutionary processes underlying acquired resistance to these compounds. PMID:26583011

The role of biofilms as environmental reservoirs of antibiotic resistance.

PubMed

Balcázar, José L; Subirats, Jéssica; Borrego, Carles M

2015-01-01

Antibiotic resistance has become a significant and growing threat to public and environmental health. To face this problem both at local and global scales, a better understanding of the sources and mechanisms that contribute to the emergence and spread of antibiotic resistance is required. Recent studies demonstrate that aquatic ecosystems are reservoirs of resistant bacteria and antibiotic resistance genes as well as potential conduits for their transmission to human pathogens. Despite the wealth of information about antibiotic pollution and its effect on the aquatic microbial resistome, the contribution of environmental biofilms to the acquisition and spread of antibiotic resistance has not been fully explored in aquatic systems. Biofilms are structured multicellular communities embedded in a self-produced extracellular matrix that acts as a barrier to antibiotic diffusion. High population densities and proximity of cells in biofilms also increases the chances for genetic exchange among bacterial species converting biofilms in hot spots of antibiotic resistance. This review focuses on the potential effect of antibiotic pollution on biofilm microbial communities, with special emphasis on ecological and evolutionary processes underlying acquired resistance to these compounds.

Towards a tolerance toolkit: Gene expression signatures enabling the emergence of resistant bacterial strains

NASA Astrophysics Data System (ADS)

Erickson, Keesha; Chatterjee, Anushree

2014-03-01

Microbial pathogens are able to rapidly acquire tolerance to chemical toxins. Developing next-generation antibiotics that impede the emergence of resistance will help avoid a world-wide health crisis. Conversely, the ability to induce rapid tolerance gains could lead to high-yielding strains for sustainable production of biofuels and commodity chemicals. Achieving these goals requires an understanding of the general mechanisms allowing microbes to become resistant to diverse toxins. We apply top-down and bottom-up methodologies to identify biological network changes leading to adaptation and tolerance. Using a top-down approach, we perform evolution experiments to isolate resistant strains, collect samples for transcriptomic and proteomic analysis, and use the omics data to inform mathematical gene regulatory models. Using a bottom-up approach, we build and test synthetic genetic devices that enable increased or decreased expression of selected genes. Unique patterns in gene expression are identified in cultures actively gaining resistance, especially in pathways known to be involved with stress response, efflux, and mutagenesis. Genes correlated with tolerance could potentially allow the design of resistance-free antibiotics or robust chemical production strains.

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.

[Does the emergence of antibiotic resistance announce the return of the dark ages?].

PubMed

Elhani, Dalèle

2011-01-01

Antibiotic revolution changed the course of modern medicine, by decreasing mortality due to bacterial infections. However, bacteria have developed several ways of resistance against all antibiotics used. In view of the rise of resistance and of its dissemination to different bacterial families, new effective antibiotics are scare and the return in the pre-antibiotic era seems to be a reality for some parts of the world. This review revises the worrying phenomenon of antibiotic resistance focusing on some examples of "superbugs", which represent a daily challenge for the medical profession, such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, extended spectrum ß-lactamae-producing Enterobacteriaceae as well as carbapenem-resistant Pseudomonas aeruginosa. Facing the emergence of the multiresistant strains, the priority is obviously to control the spread of these microorganisms. It is only through the prudent use of antimicrobial drugs and the introduction of new and effective antibiotics that the antibiotic resistance will be slowed down and that we continue to treat bacterial infections.

Characterization of multiple antibiotic resistance of culturable microorganisms and metagenomic analysis of total microbial diversity of marine fish sold in retail shops in Mumbai, India.

PubMed

Naik, Onkar A; Shashidhar, Ravindranath; Rath, Devashish; Bandekar, Jayant R; Rath, Archana

2018-03-01

Marine fish species were analyzed for culturable and total metagenomic microbial diversity, antibiotic resistance (AR) pattern, and horizontal gene transfer in culturable microorganisms. We observed a high AR microbial load of 3 to 4 log CFU g -1 . Many fish pathogens like Providencia, Staphylococcus, Klebsiella pneumoniae, Enterobacter, Vagococcus, and Aeromonas veronii were isolated. Photobacterium and Vibrio were two major fish and human pathogens which were identified in the fish metagenome. Other pathogens that were identified were Shewanella, Acinetobacter, Psychrobacter, and Flavobacterium. Most of these pathogens were resistant to multiple antibiotics such as erythromycin, kanamycin, neomycin, streptomycin, penicillin, cefotaxime, bacitracin, rifampicin, trimethoprim, ciprofloxacin, and doxycycline with a high multiple antibiotic resistance index of 0.54-0.77. The fish microflora showed high prevalence of AR genes like bla TEM , Class I integron, tetA, aph(3')-IIIa, ermB, aadA, and sul1. Nineteen of 26 AR isolates harbored Class I integrons showing high co-resistance to trimethoprim, kanamycin, doxycycline, and cefotaxime. Mobile R-plasmids from 6 of the 12 AR pathogens were transferred to recipient E. coli after conjugation. The transconjugants harbored the same R-plasmid carrying bla CTX-M , dfr1, tetA, bla TEM , and cat genes. This study confirms that fish is a potential carrier of AR pathogens which can enter the human gut via food chain. To the best of our knowledge, this is the first study in the Indian subcontinent reporting a direct evidence of spread of AR pathogens to humans from specific marine fish consumption.

Determination of integron frequency by a polymerase chain reaction-restriction fragment length polymorphism method in multidrug-resistant Escherichia coli, which causes urinary tract infections.

PubMed

Fallah, Fatemeh; Karimi, Abdollah; Goudarzi, Mehdi; Shiva, Farideh; Navidinia, Masoumeh; Jahromi, Mana Hadipour; Sajadi Nia, Raheleh Sadat

2012-12-01

The purpose of this study was to determine the presence of integrons in Escherichia coli, which cause urinary tract infections, and to define the association between integrons and antimicrobial susceptibility. Susceptibility of 200 isolates from urine samples of patients suffering from urinary tract infections to 13 antibiotics was determined by the Kirby-Bauer disk diffusion method. The existence of class1 and 2 integrons in resistant isolates was assessed by polymerase chain reaction-restriction fragment length polymorphism and sequencing. Antibiotic resistance patterns were observed as follows: amoxicillin 78%, tetracycline 76.1%, co-trimoxazole 67.7%, cephalotin 60%, nalidixic acid 57.4%, chloramphenicol 49%, gentamicin 46.4%, ceftazidim 38.1%, ciprofloxacin 36.2%, nitrofurantoin 33.5%, amikacin 32.1%, norfloxacin 36.1%, and imipenem 27.1%. Of 200 isolates, 155 (77.5%) were multidrug resistant (MDR). The existence of integrons was confirmed in 50.3% of isolates. Three class 1 integron types, aadA2 being the most frequently found, and four class 2 integron types are described. Significant association between resistance to gentamicin, co-trimoxazole, cephalotin, ceftazidim, imipenem, chloramphenicol, and nalidixic acid with the existence of integrons was observed. Multidrug resistance suggests that the strategy for treatment of patients with E.coli infections needs to be revised. Furthermore, it was shown that integrons may be partly responsible for multidrug resistance. Imipenem and norfloxacin were the most effective antibiotics against isolates.

The culturable soil antibiotic resistome: a community of multi-drug resistant bacteria.

PubMed

Walsh, Fiona; Duffy, Brion

2013-01-01

Understanding the soil bacterial resistome is essential to understanding the evolution and development of antibiotic resistance, and its spread between species and biomes. We have identified and characterized multi-drug resistance (MDR) mechanisms in the culturable soil antibiotic resistome and linked the resistance profiles to bacterial species. We isolated 412 antibiotic resistant bacteria from agricultural, urban and pristine soils. All isolates were multi-drug resistant, of which greater than 80% were resistant to 16-23 antibiotics, comprising almost all classes of antibiotic. The mobile resistance genes investigated, (ESBL, bla NDM-1, and plasmid mediated quinolone resistance (PMQR) resistance genes) were not responsible for the respective resistance phenotypes nor were they present in the extracted soil DNA. Efflux was demonstrated to play an important role in MDR and many resistance phenotypes. Clinically relevant Burkholderia species are intrinsically resistant to ciprofloxacin but the soil Burkholderia species were not intrinsically resistant to ciprofloxacin. Using a phenotypic enzyme assay we identified the antibiotic specific inactivation of trimethoprim in 21 bacteria from different soils. The results of this study identified the importance of the efflux mechanism in the soil resistome and variations between the intrinsic resistance profiles of clinical and soil bacteria of the same family.

Antibiotic use and resistance in animals: Belgian initiatives.

PubMed

Daeseleire, Els; De Graef, Evelyne; Rasschaert, Geertrui; De Mulder, Thijs; Van den Meersche, Tina; Van Coillie, Els; Dewulf, Jeroen; Heyndrickx, Marc

2016-05-01

The widespread use of antibiotics in animals is causing concerns about the growing risk for development and the spread of antibiotic-resistant bacteria. Antibiotic consumption is higher in animals than in humans as reported in a joint publication of EFSA (European Food Safety Agency), ECDC (European Centre for Disease Prevention and Control), and EMA (European Medicines Agency) using data from 2011 and 2012. Both in humans and animals, positive associations between the consumption of antibiotics and resistant bacteria are observed. Responsible use of antibiotics in humans and animals should therefore be promoted. In this paper some general aspects of antibiotic resistance such as microbiological versus clinical resistance, intrinsic versus acquired resistance, resistance mechanisms, and transfer of resistance are briefly introduced. In 2012, the Belgian Center of Expertise on Antimicrobial Consumption and Resistance in Animals (AMCRA) was founded. Its mission is to collect and analyze all data related to antibiotic use and resistance in animals in Belgium and to communicate these findings in a neutral and objective manner. One of AMCRA's 10 objectives is a 50% reduction in antibiotic consumption in veterinary medicine in Belgium by 2020. The aim of this paper is to report on the achievements of this national project. The Institute for Agricultural and Fisheries Research (ILVO, Merelbeke-Melle), in collaboration with Ghent University, is currently working on three nationally funded projects on antibiotic resistance in animal husbandry. In the first project, an in vitro model is used to study the influence of low antibiotic concentrations due to carry-over after production and usage of medicated feed on the development of resistance in the pig gut. Part of that project is to develop a quantitative risk assessment model. A second project focuses on tracking excreted antibiotics used in pig rearing and their influence on the development of antibiotic resistance in pig manure and the environment. In the last project, the relation between the use of biocides in animal husbandry and antibiotic resistance development are being studied. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

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

PubMed

Heward, E; Cullen, M; Hobson, J

2018-04-01

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

Antagonistic Activity of Nocardia brasiliensis PTCC 1422 Against Isolated Enterobacteriaceae from Urinary Tract Infections.

PubMed

Jalali, Hossnieh Kafshdar; Salamatzadeh, Abdolreza; Jalali, Arezou Kafshdar; Kashani, Hamed Haddad; Asbchin, Salman Ahmadi; Issazadeh, Khosro

2016-03-01

The main drawback of current antibiotic therapies is the emergence and rapid increase in antibiotic resistance. Nocardiae are aerobic, Gram-positive, catalase-positive, non-motile actinomycetes. Nocardia brasiliensis was reported as antibiotic producer. The purpose of the study was to determine antibacterial activity of N. brasiliensis PTCC 1422 against isolated Enterobacteriaceae from urinary tract infections (UTIs). The common bacteria from UTIs were isolated from hospital samples. Antimicrobial susceptibility test was performed for the isolated pathogens using Kirby-Bauer disk diffusion method according to clinical and Laboratory Standards Institute guideline. Antagonistic activity of N. brasiliensis PTCC 1422 was examined with well diffusion methods. Supernatant of N. brasiliensis PTCC 1422 by submerged culture was analyzed with gas chromatography-mass spectrometry. Isolated strains included Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Proteus mirabilis. The most common pathogen isolated was E. coli (72.5%). Bacterial isolates revealed the presence of high levels of antimicrobial resistances to ceftriaxone and low levels of resistance to cephalexin. Supernatant of N. brasiliensis PTCC 1422 showed antibacterial activity against all of the isolated microorganisms in well diffusion method. The antibiotic resistance among the uropathogens is an evolving process, so a routine surveillance to monitor the etiologic agents of UTI and the resistance pattern should be carried out timely to choose the most effective empirical treatment by the physicians. Our present investigation indicates that the substances present in the N. brasiliensis PTCC 1422 could be used to inhibit the growth of human pathogen. Antibacterial resistance among bacterial uropathogen is an evolving process. Therefore, in the field on the need of re-evaluation of empirical treatment of UTIs, our present. The study has demonstrated that N. brasiliensis PTCC 1422 has a high potential for the treatment of UTIs.

Incidence of antibiotics resistance among uropathogens in Omani children presenting with a single episode of urinary tract infection.

PubMed

Sharef, Sharef W; El-Naggari, Mohamed; Al-Nabhani, Dana; Al Sawai, Ali; Al Muharrmi, Zakaria; Elnour, Ibtisam

2015-01-01

Urinary tract infection (UTI) is one of the most common community-acquired infections. Different organisms can be the cause of UTI in children, with resistance to antibiotics becoming a significant problem in the choice of treatment. Worldwide studies have documented the prevalence of uropathogens in different countries. However, there is no previous study documenting the incidence of different uropathogens in Oman. We aim to report the most common uropathogens and their antibiotic sensitivity patterns in children presenting with documented, single episode UTI at a tertiary hospital in Oman. A retrospective analysis of all Omani children below 14 years who presented with a case of first documented UTI to SQUH between September 2008 and August 2012 was conducted. Data were obtained from the patients' electronic records in the hospital information system. Data were then analyzed using SSPS (Statistical Package for Social Sciences program, Version 20, IBM, Chicago, IL, USA). In the retrospective review of all urine cultures, 438 positive urine cultures were identified. Out of those, 208 (47.5%) belonged to children with their first episode of UTI. Thirty-three patients were excluded and 75 patients were included in the final analysis. Escherichia coli was the most frequently encountered uropathogen in our cohort (69%), followed by Klebsiella pneumoniae infection (17%). Nearly half (46.6%) of these two common organism were resistant to Cotrimoxazole, while 31% of them were resistant to Augmentin. Twenty-four percent of the E. coli and K. pneumoniae strains were resistant to Cefuroxime, and only 10% were resistant to nitrofurantoin. Both Augmentin and Cotrimoxazole should not be the first line antibiotics to treat UTI. Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Results from the Survey of Antibiotic Resistance (SOAR) 2014-16 in the Czech Republic.

PubMed

Torumkuney, D; Zemlickova, H; Maruscak, M; Morrissey, I

2018-04-01

To determine the antibiotic susceptibility of isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2014-16 from patients with community-acquired respiratory infections in the Czech Republic. MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. S. pneumoniae isolates (n = 200) showed high rates of susceptibility (>95%) to amoxicillin, amoxicillin/clavulanic acid, penicillin [intravenous (iv) non-meningitis], ceftriaxone, cefuroxime and the fluoroquinolones using CLSI breakpoints. Susceptibility to cefaclor and trimethoprim/sulfamethoxazole was 94%-94.5%, to penicillin (oral) 91.5% and to the macrolides 89.5%. Susceptibility of H. influenzae (n = 197) to amoxicillin/clavulanic acid, ceftriaxone, cefuroxime, azithromycin and the fluoroquinolones was ≥98% by CLSI criteria. Rates of susceptibility to the remaining agents were ≥75% except for clarithromycin at 37.1%. Great variability was seen across breakpoints, especially for the macrolides, cefaclor and cefuroxime (oral), 98.0% of H. influenzae showing susceptibility to the latter by CLSI criteria, 69.5% by PK/PD and 1.5% by EUCAST standards. The β-lactamase rate was 13.7% with no β-lactamase-negative-ampicillin-resistant (BLNAR) isolates by CLSI criteria. Antibiotic resistance among the two major respiratory pathogens remained low in the Czech Republic. These findings support local clinicians in continuing the historically restrictive use of antibiotics in the Czech Republic, with selection of narrower-spectrum agents for the empirical therapy of community-acquired respiratory tract infections. This highlights one of the great benefits of continuous surveillance of antimicrobial resistance: knowledge of current local resistance patterns reduces the need to choose broad-spectrum agents that contribute to increasing resistance worldwide.

The diversities of staphylococcal species, virulence and antibiotic resistance genes in the subclinical mastitis milk from a single Chinese cow herd.

PubMed

Xu, Jia; Tan, Xiao; Zhang, Xinyu; Xia, Xiaoli; Sun, Huaichang

2015-11-01

Staphylococci are the leading pathogens of bovine mastitis which is difficult to control. However, the published data on the prevalence of staphylococcal species, virulence and antibiotic resistance genes in bovine mastitis from China are limited. In this study, 104 out of 209 subclinical mastitis milk samples from a single Chinese dairy herd were cultured-positive for staphylococci (49.8%), which were further identified as coagulase-positive staphylococci (CPS) or coagulase-negative staphylococci (CNS). According to the partial tuf and/or 16S rRNA gene sequence, the 28 CPS isolates were confirmed to be Staphylococcus aureus (26.9%), and 76 CNS isolates were assigned to 13 different species (73.1%) with Staphylococcus arlettae, Staphylococcus sciuri, Staphylococcus xylosus and Staphylococcus chromogenes as the dominant species. In the 28 S. aureus isolates, the most prevalent general virulence genes were coa, Ig and eno (100%), followed by hla (96.4%), hlb (92.9%), fib (92.9%), clfA (89.3%), clfB (85.7%) and nuc (85.7%). Both exotoxin and biofilm-associated genes were significantly less prevalent than the previously reported. Although 19 different virulence gene patterns were found, only one was dominant (32.1%). The prevalence of blaZ (82.1%) or mecA gene (35.7%) was much higher than the previously reported. In the 76 CNS isolates, the virulence genes were significantly less prevalent than that in the S. aureus isolates. Among the 4 main CNS species, S. chromogenes (n = 12) was the only species with high percentage (75%) of blaZ gene, while S. sciuri (n = 12) was the only species with the high percentage (66.7%) of mecA gene. The most of antibiotic resistance genes were present as multi-resistance genes, and the antibiotic resistances were attributed by different resistance genes between resistant S. aureus and CNS isolates. These data suggest that the prevalence of staphylococcal species, virulence and antibiotic resistance in the mastitis milk from the Chinese dairy herd are different from the previously reported, and that the herd- or farm-based diagnosis of staphylococcal bovine mastitis is required. Copyright © 2015 Elsevier Ltd. All rights reserved.

Metagenomic profiling of ARGs in airborne particulate matters during a severe smog event.

PubMed

Hu, Jialin; Zhao, Fuzheng; Zhang, Xu-Xiang; Li, Kan; Li, Chaoran; Ye, Lin; Li, Mei

2018-02-15

Information is currently limited regarding the distribution of antibiotic resistance genes (ARGs) in smog and their correlations with airborne bacteria. This study characterized the diversity and abundance of ARGs in the particulate matters (PMs) of severe smog based on publicly available metagenomic data, and revealed the occurrence of 205 airborne ARG subtypes, including 31 dominant ones encoding resistance to 11 antibiotic types. Among the detectable ARGs, tetracycline, β-lactam and aminoglycoside resistance genes had the highest abundance, and smog and soil had similar composition characteristics of ARGs. During the smog event, the total abundance of airborne ARGs ranged from 4.90 to 38.07ppm in PM 2.5 samples, and from 7.61 to 38.49ppm in PM 10 samples, which were 1.6-7.7 times and 2.1-5.1 times of those in the non-smog day, respectively. The airborne ARGs showed complicated co-occurrence patterns, which were heavily influenced by the interaction of bacterial community, and physicochemical and meteorological factors. Lactobacillus and sulfonamide resistance gene sul1 were determined as keystones in the co-occurrence network of microbial taxa and airborne ARGs. The results may help to understand the distribution patterns of ARGs in smog for the potential health risk evaluation. Copyright © 2017 Elsevier B.V. All rights reserved.

Clinical and molecular epidemiology of hospital Enterococcus faecalis isolates in eastern France.

PubMed

Mulin, Blandine; Bailly, Pascale; Thouverez, Michelle; Cailleaux, Vincent; Cornette, Christian; Dupont, Marie-Jeanne; Talon, Daniel

1999-03-01

OBJECTIVE: To report on the occurrence of Enterococcus faecalis hospital isolates obtained during 1 year in hospitals in the Franche-Comté region of France. METHODS: Clinical isolates of E. faecalis of different antibiotic susceptibility phenotypes from hospitalized patients were characterized by pulsed-field gel electrophoresis. Patients with positive cultures were investigated by three case-control studies to identify risk factors for colonization/infection. RESULTS: The crude incidence of colonization/infection was 2.37%, and 4-day and 7-day colonization rates after admission were 10.0% and 6.36%, respectively. The rates of high-level resistance to kanamycin (HLKR) and to gentamicin (HLGR) were 47.1% and 7.1%, respectively. No isolate was resistant to glycopeptides or produced beta-lactamase. The 209 hospital isolates obtained during the study yielded 98 major DNA patterns, of which two were major epidemic patterns including HLKR isolates. No single factor was significantly associated with colonization/infection by HLKR isolates. The length of hospitalization before isolation was associated with colonization by HLGR isolates. CONCLUSIONS: The isolation frequency of E. faecalis strains with acquired resistance to aminoglycoside antibiotics, and the wide dissemination of resistant strains with characteristics that allow them to persist and spread, argue for further large prospective surveys of clinical isolates of E. faecalis in hospitals.

Vancomycin intermediate-resistant Staphylococcus aureus (VISA) isolated from a patient who never received vancomycin treatment.

PubMed

Zhu, Xuhui; Liu, Cailin; Gao, Sui; Lu, Yanfang; Chen, Zhongju; Sun, Ziyong

2015-04-01

With the abuse of antibiotics, the methicillin-resistant Staphylococcus aureus (MRSA) strain became prevalent. Furthermore, Staphylococcus aureus with a character of vancomycin intermediate-resistance (VISA) has been found globally since the first report in Japan. The main objectives of this study were to report a case of VISA isolated from a Chinese patient who had never undergone Vancomycin treatment, and to determine its molecular character. A total of 9 strains were recovered from a patient during the therapeutic process. Antimicrobial susceptibility testing was performed to determine their antibiotic susceptibility patterns. To detect the VISA strain's molecular epidemiological features, growth and morphological characters, we used multilocus sequence typing, autolysis assay and transmission electric microscope tests. Pulsed-field gel electrophoresis (PFGE) was performed to characterize the heterogeneities of all isolates. One isolate was found to exhibit vancomycin intermediated-resistant with MIC of 8 μg/ml. It was ST239-T030-agr-1, had thickened cell wall, and displayed a slower growth rate and reduced susceptibility to Triton X-100-induced autolysis than other strains. All 9 strains exhibited the same PFGE pattern. This is the first report of VISA found in central China from a patient who had never received vancomycin treatment. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

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/.

Isolated cell behavior drives the evolution of antibiotic resistance

PubMed Central

Artemova, Tatiana; Gerardin, Ylaine; Dudley, Carmel; Vega, Nicole M; Gore, Jeff

2015-01-01

Bacterial antibiotic resistance is typically quantified by the minimum inhibitory concentration (MIC), which is defined as the minimal concentration of antibiotic that inhibits bacterial growth starting from a standard cell density. However, when antibiotic resistance is mediated by degradation, the collective inactivation of antibiotic by the bacterial population can cause the measured MIC to depend strongly on the initial cell density. In cases where this inoculum effect is strong, the relationship between MIC and bacterial fitness in the antibiotic is not well defined. Here, we demonstrate that the resistance of a single, isolated cell—which we call the single-cell MIC (scMIC)—provides a superior metric for quantifying antibiotic resistance. Unlike the MIC, we find that the scMIC predicts the direction of selection and also specifies the antibiotic concentration at which selection begins to favor new mutants. Understanding the cooperative nature of bacterial growth in antibiotics is therefore essential in predicting the evolution of antibiotic resistance. PMID:26227664

Antibiotic-resistant genes and antibiotic-resistant bacteria in the effluent of urban residential areas, hospitals, and a municipal wastewater treatment plant system.

PubMed

Li, Jianan; Cheng, Weixiao; Xu, Like; Strong, P J; Chen, Hong

2015-03-01

In this study, we determined the abundance of 8 antibiotics (3 tetracyclines, 4 sulfonamides, and 1 trimethoprim), 12 antibiotic-resistant genes (10 tet, 2 sul), 4 antibiotic-resistant bacteria (tetracycline, sulfamethoxazole, and combined resistance), and class 1 integron integrase gene (intI1) in the effluent of residential areas, hospitals, and municipal wastewater treatment plant (WWTP) systems. The concentrations of total/individual targets (antibiotics, genes, and bacteria) varied remarkably among different samples, but the hospital samples generally had a lower abundance than the residential area samples. The WWTP demonstrated removal efficiencies of 50.8% tetracyclines, 66.8% sulfonamides, 0.5 logs to 2.5 logs tet genes, and less than 1 log of sul and intI1 genes, as well as 0.5 log to 1 log removal for target bacteria. Except for the total tetracycline concentration and the proportion of tetracycline-resistant bacteria (R (2) = 0.330, P < 0.05), there was no significant correlation between antibiotics and the corresponding resistant bacteria (P > 0.05). In contrast, various relationships were identified between antibiotics and antibiotic resistance genes (P < 0.05). Tet (A) and tet (B) displayed noticeable relationships with both tetracycline and combined antibiotic-resistant bacteria (P < 0.01).

Predictive Studies Suggest that the Risk for the Selection of Antibiotic Resistance by Biocides Is Likely Low in Stenotrophomonas maltophilia

PubMed Central

Sánchez, María Blanca; Decorosi, Francesca; Viti, Carlo; Oggioni, Marco Rinaldo; Martínez, José Luis; Hernández, Alvaro

2015-01-01

Biocides are used without restriction for several purposes. As a consequence, large amounts of biocides are released without any control in the environment, a situation that can challenge the microbial population dynamics, including selection of antibiotic resistant bacteria. Previous work has shown that triclosan selects Stenotrophomonas maltophilia antibiotic resistant mutants overexpressing the efflux pump SmeDEF and induces expression of this pump triggering transient low-level resistance. In the present work we analyze if two other common biocides, benzalkonium chloride and hexachlorophene, trigger antibiotic resistance in S. maltophilia. Bioinformatic and biochemical methods showed that benzalkonium chloride and hexachlorophene bind the repressor of smeDEF, SmeT. Only benzalkonium chloride triggers expression of smeD and its effect in transient antibiotic resistance is minor. None of the hexachlorophene-selected mutants was antibiotic resistant. Two benzalkonium chloride resistant mutants presented reduced susceptibility to antibiotics and were impaired in growth. Metabolic profiling showed they were more proficient than their parental strain in the use of some dipeptides. We can then conclude that although bioinformatic predictions and biochemical studies suggest that both hexachlorophene and benzalkonium chloride should induce smeDEF expression leading to transient S. maltophilia resistance to antibiotics, phenotypic assays showed this not to be true. The facts that hexachlorophene resistant mutants are not antibiotic resistant and that the benzalkonium chloride resistant mutants presenting altered susceptibility to antibiotics were impaired in growth suggests that the risk for the selection (and fixation) of S. maltophilia antibiotic resistant mutants by these biocides is likely low, at least in the absence of constant selection pressure. PMID:26201074

Antibiotic sensitivity pattern from pregnant women with urinary tract infection in Bangalore, India.

PubMed

Sibi, G; Kumari, Pinki; Kabungulundabungi, Neema

2014-09-01

To determine the antibacterial profile of pregnant women with urinaty tract infections and analyze the antibiotic sensitivity pattern for the effective treatment. A total of 395 urine samples from pregnant women with different gestational age were processed for the isolation of uropathogens and tested against eight groups of antibiotics namely penicillins, cephalosporins, fluoroquinolones, aminoglycosides, macrolides, lincosamides, glycopeptides and sulfonamides. A positive culture percentage of 46.6% was obtained with the highest urinary tract infection in third trimester gestational age. Among the uropathogens isolated, 85.6% were Gram negative and 14.4% were Gram positive with Escherichia coli as the predominant bacteria (43.9%) followed by Klebsiella oxytoca (19.4%) and Klebsiella pneumoniae (13.3%). Antibiotic sensitivity assay revealed that amikacin had the highest overall sensitivity (n=136; 76.7%) and the subsequent highest sensitivity was observed with ciprofloxacin (n=132; 73.3%), clindamycin (n=124; 68.9%), cefotaxime (n=117; 65%) and nalidixic acid (n=115; 63.9%). The findings revealed that uropathogens were more resistant to penicillins, macrolides and glycopeptides which restrict their use in treating urinaty tract infections during pregnancy. In conclusion, common causative bacteria and their antibiotic sensitivity pattern are to be determined along with their safety to mother and fetus for the effective treatment of urinary tract infections during pregnancy. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

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

PubMed

Andabati, G; Byamugisha, J

2010-12-01

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

Microbial selectivity of UV treatment on antibiotic-resistant heterotrophic bacteria in secondary effluents of a municipal wastewater treatment plant.

PubMed

Guo, Mei-Ting; Yuan, Qing-Bin; Yang, Jian

2013-10-15

Little is known about the microbial selectivity of UV treatment for antibiotic resistant bacteria, and the results of limited studies are conflicting. To understand the effect of UV disinfection on antibiotic resistant bacteria, both total heterotrophic bacteria and antibiotic resistant bacteria (including cephalexin-, ciprofloxacin-, erythromycin-, gentamicin-, vancomycin-, sulfadiazine-, rifampicin-, tetracycline- and chloramphenicol-resistant bacteria) were examined in secondary effluent samples from a municipal wastewater treatment plant. Bacteria resistant to both erythromycin and tetracycline were chosen as the representative of multiple-antibiotic-resistant bacteria and their characteristics after UV treatment were also investigated. UV disinfection results in effective inactivation for total heterotrophic bacteria, as well as all antibiotic resistant bacteria. After UV treatment at a fluence of 5 mJ/cm(2), the log reductions of nine types of antibiotic resistant bacteria varied from 1.0 ± 0.1 to 2.4 ± 0.1. Bacteria resistant to both erythromycin and tetracycline had a similar fluence response as did total heterotrophic bacteria. The findings suggest that UV disinfection could eliminate antibiotic resistance in wastewater treatment effluents and thus ensure public health security. Our experimental results indicated that UV disinfection led to enrichment of bacteria with resistance to sulfadiazine, vancomycin, rifampicin, tetracycline and chloramphenicol, while the proportions of cephalexin-, erythromycin-, gentamicin- and ciprofloxacin-resistant bacteria in the wastewater decreased. This reveals the microbial selectivity of UV disinfection for antibiotic resistant bacteria. Copyright © 2013 Elsevier Ltd. All rights reserved.

Environmental and Public Health Implications of Water Reuse: Antibiotics, Antibiotic Resistant Bacteria, and Antibiotic Resistance Genes

PubMed Central

Hong, Pei-Ying; Al-Jassim, Nada; Ansari, Mohd Ikram; Mackie, Roderick I.

2013-01-01

Water scarcity is a global problem, and is particularly acute in certain regions like Africa, the Middle East, as well as the western states of America. A breakdown on water usage revealed that 70% of freshwater supplies are used for agricultural irrigation. The use of reclaimed water as an alternative water source for agricultural irrigation would greatly alleviate the demand on freshwater sources. This paradigm shift is gaining momentum in several water scarce countries like Saudi Arabia. However, microbial problems associated with reclaimed water may hinder the use of reclaimed water for agricultural irrigation. Of particular concern is that the occurrence of antibiotic residues in the reclaimed water can select for antibiotic resistance genes among the microbial community. Antibiotic resistance genes can be associated with mobile genetic elements, which in turn allow a promiscuous transfer of resistance traits from one bacterium to another. Together with the pathogens that are present in the reclaimed water, antibiotic resistant bacteria can potentially exchange mobile genetic elements to create the “perfect microbial storm”. Given the significance of this issue, a deeper understanding of the occurrence of antibiotics in reclaimed water, and their potential influence on the selection of resistant microorganisms would be essential. In this review paper, we collated literature over the past two decades to determine the occurrence of antibiotics in municipal wastewater and livestock manure. We then discuss how these antibiotic resistant bacteria may impose a potential microbial risk to the environment and public health, and the knowledge gaps that would have to be addressed in future studies. Overall, the collation of the literature in wastewater treatment and agriculture serves to frame and identify potential concerns with respect to antibiotics, antibiotic resistant bacteria, and antibiotic resistance genes in reclaimed water. PMID:27029309

Community acquired infections in older patients admitted to hospital from care homes versus the community: cohort study of microbiology and outcomes.

PubMed

Marwick, Charis; Santiago, Virginia Hernandez; McCowan, Colin; Broomhall, Janice; Davey, Peter

2013-02-06

Residents of care homes are at risk of colonisation and infection with antibiotic resistant bacteria, but there is little evidence that antibiotic resistance among such patients is associated with worse outcomes than among older people living in their own homes. Our aim was to compare the prevalence of antibiotic resistant bacteria and clinical outcomes in older patients admitted to hospital with acute infections from care homes versus their own homes. We enrolled patients admitted to Ninewells Hospital in 2005 who were older than 64 years with onset of acute community acquired respiratory tract, urinary tract or skin and soft tissue infections, and with at least one sample sent for culture. The primary outcome was 30 day mortality, adjusted for age, sex, Charlson Index of co-morbidity, sepsis severity, presence of resistant isolates and resistance to initial therapy. 161 patients were identified, 60 from care homes and 101 from the community. Care home patients were older, had more co-morbidities, and higher rates of resistant bacteria, including MRSA and Gram negative organisms resistant to co-amoxiclav, cefuroxime and/or ciprofloxacin, overall (70% versus 36%, p = 0.026). 30 day mortality was high in both groups (30% in care home patients and 24% in comparators). In multivariate logistic regression we found that place of residence did not predict 30 day mortality (adjusted odds ratio (OR) for own home versus care home 1.01, 95% CI 0.40-2.52, p = 0.984). Only having severe sepsis predicted 30 day mortality (OR 10.09, 95% CI 3.37-30.19, p < 0.001), after adjustment for age, sex, co-morbidity, presence of resistant bacteria, resistance to initial therapy, and place of residence. Older patients admitted with acute infection had high 30 day mortality. Patients from care homes were more likely to have resistant organisms but high levels of antimicrobial resistance were found in both groups. Thus, we recommend that antibiotic therapies active against resistant organisms, guided by local resistance patterns, should be considered for all older patients admitted with severe sepsis regardless of their place of residence.

The abundance of antibiotic resistance genes in human guts has correlation to the consumption of antibiotics in animal

PubMed Central

Hu, Yongfei; Yang, Xi; Lu, Na; Zhu, Baoli

2014-01-01

Increasing evidence has accumulated to support that the human gut is a reservoir for antibiotic resistance genes. We previously identified more than 1000 genes displaying high similarity with known antibiotic resistance genes in the human gut gene set generated from the Chinese, Danish, and Spanish populations. Here, first, we add our new understanding of antibiotic resistance genes in the US and the Japanese populations; next, we describe the structure of a vancomycin-resistant operon in a Danish sample; and finally, we provide discussions on the correlation of the abundance of resistance genes in human gut with the antibiotic consumption in human medicine and in animal husbandry. These results, combined with those we published previously, provide comprehensive insights into the antibiotic resistance genes in the human gut microbiota at a population level. PMID:24637798

The abundance of antibiotic resistance genes in human guts has correlation to the consumption of antibiotics in animal.

PubMed

Hu, Yongfei; Yang, Xi; Lu, Na; Zhu, Baoli

2014-01-01

Increasing evidence has accumulated to support that the human gut is a reservoir for antibiotic resistance genes. We previously identified more than 1000 genes displaying high similarity with known antibiotic resistance genes in the human gut gene set generated from the Chinese, Danish, and Spanish populations. Here, first, we add our new understanding of antibiotic resistance genes in the US and the Japanese populations; next, we describe the structure of a vancomycin-resistant operon in a Danish sample; and finally, we provide discussions on the correlation of the abundance of resistance genes in human gut with the antibiotic consumption in human medicine and in animal husbandry. These results, combined with those we published previously, provide comprehensive insights into the antibiotic resistance genes in the human gut microbiota at a population level.

Management Options For Reducing The Release Of Antibiotics And Antibiotic Resistance Genes To The Environment

EPA Science Inventory

Background: There is growing concern worldwide about the role of polluted soil and water - 77 environments in the development and dissemination of antibiotic resistance. 78 Objective: To identify management options for reducing the spread of antibiotics and 79 antibiotic resist...

The impact of antibiotic use on transmission of resistant bacteria in hospitals: Insights from an agent-based model.

PubMed

Almagor, Jonatan; Temkin, Elizabeth; Benenson, Itzhak; Fallach, Noga; Carmeli, Yehuda

2018-01-01

Extensive antibiotic use over the years has led to the emergence and spread of antibiotic resistant bacteria (ARB). Antibiotic resistance poses a major threat to public health since for many infections antibiotic treatment is no longer effective. Hospitals are focal points for ARB spread. Antibiotic use in hospitals exerts selective pressure, accelerating the spread of ARB. We used an agent-based model to explore the impact of antibiotics on the transmission dynamics and to examine the potential of stewardship interventions in limiting ARB spread in a hospital. Agents in the model consist of patients and health care workers (HCW). The transmission of ARB occurs through contacts between patients and HCW and between adjacent patients. In the model, antibiotic use affects the risk of transmission by increasing the vulnerability of susceptible patients and the contagiousness of colonized patients who are treated with antibiotics. The model shows that increasing the proportion of patients receiving antibiotics increases the rate of acquisition non-linearly. The effect of antibiotics on the spread of resistance depends on characteristics of the antibiotic agent and the density of antibiotic use. Antibiotic's impact on the spread increases when the bacterial strain is more transmissible, and decreases as resistance prevalence rises. The individual risk for acquiring ARB increases in parallel with antibiotic density both for patients treated and not treated with antibiotics. Antibiotic treatment in the hospital setting plays an important role in determining the spread of resistance. Interventions to limit antibiotic use have the potential to reduce the spread of resistance, mainly by choosing an agent with a favorable profile in terms of its impact on patient's vulnerability and contagiousness. Methods to measure these impacts of antibiotics should be developed, standardized, and incorporated into drug development programs and approval packages.

Bacterial susceptibility patterns in patients with spinal cord injury and disorder (SCI/D): an opportunity for customized stewardship tools.

PubMed

Suda, K J; Patel, U C; Sabzwari, R; Cao, L; Ramanathan, S; Hill, J N; Evans, C T

2016-11-01

Retrospective observational study of bacterial susceptibilities in Veterans with SCI/D as compared to a general patient population. The purpose of this project was to evaluate the prevalence and susceptibility of bacteria isolated from spinal cord injury and disorder (SCI/D) patients as compared with a general patient population and determine whether a SCI/D-specific antibiogram, a report of bacterial susceptibilities used to guide empiric antibiotic selection, would be a useful stewardship tool. Veterans Affairs Medical Center located in Cook county, IL, USA. Microbiology reports from 1 October 2012 to 30 September 2013 were compiled into a SCI/D-specific antibiogram and compared to a non-SCI/D antibiogram. Persons with positive cultures and SCI/D were younger and had a higher Charlson Index as compared to non-SCI/D patients (P<0.0001 for both). Five thousand one hundred and thirty-one unique isolate cultures were evaluated (SCI/D=23.0%). Frequencies of pathogens isolated in SCI/D and non-SCI/D differed. Methicillin-resistant Staphylococcus aureus occurred more frequently in SCI/D (27.8% vs 55.4%; P<0.0001). Gram-negatives had generally lower susceptibilities in SCI/D and a higher frequency of organisms producing extended-spectrum Beta-lactamases (17.6% vs 5.0%; P<0.0001), carbapenem-resistant Enterobacteriaceae (2.4% vs 0.5%; P<0.0001), carbapenem resistance (7.6% vs 2.4%; P<0.0001) and isolates resistant to ⩾3 antibiotic classes (60.7% vs 28.0%; P=0.0001). Different pathogens with poorer susceptibilities are isolated in SCI/D. Thus an SCI/D-specific antibiogram reflective of resistance patterns in these patients may increase the appropriateness of empiric antibiotic selection. The frequency of multi-drug resistant organisms in cultures obtained from patients with SCI/D is worrisome.

Probing minority population of antibiotic-resistant bacteria.

PubMed

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

2016-06-15

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

Impact of dairy manure pre-application treatment on manure composition, soil dynamics of antibiotic resistance genes, and abundance of antibiotic-resistance genes on vegetables at harvest.

PubMed

Tien, Yuan-Ching; Li, Bing; Zhang, Tong; Scott, Andrew; Murray, Roger; Sabourin, Lyne; Marti, Romain; Topp, Edward

2017-03-01

Manuring ground used for crop production is an important agricultural practice. Should antibiotic-resistant enteric bacteria carried in the manure be transferred to crops that are consumed raw, their consumption by humans or animals will represent a route of exposure to antibiotic resistance genes. Treatment of manures prior to land application is a potential management option to reduce the abundance of antibiotic resistance genes entrained with manure application. In this study, dairy manure that was untreated, anaerobically digested, mechanically dewatered or composted was applied to field plots that were then cropped to lettuce, carrots and radishes. The impact of treatment on manure composition, persistence of antibiotic resistance gene targets in soil following application, and distribution of antibiotic resistance genes and bacteria on vegetables at harvest was determined. Composted manure had the lowest abundance of antibiotic resistance gene targets compared to the other manures. There was no significant difference in the persistence characteristics of antibiotic resistance genes following land application of the various manures. Compared to unmanured soil, antibiotic resistance genes were detected more frequently in soil receiving raw or digested manure, whereas they were not in soil receiving composted manure. The present study suggests that vegetables grown in ground receiving raw or digested manure are at risk of contamination with manure-borne antibiotic resistant bacteria, whereas vegetables grown in ground receiving composted manure are less so. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Impact of manure fertilization on the abundance of antibiotic-resistant bacteria and frequency of detection of antibiotic resistance genes in soil and on vegetables at harvest.

PubMed

Marti, Romain; Scott, Andrew; Tien, Yuan-Ching; Murray, Roger; Sabourin, Lyne; Zhang, Yun; Topp, Edward

2013-09-01

Consumption of vegetables represents a route of direct human exposure to bacteria found in soil. The present study evaluated the complement of bacteria resistant to various antibiotics on vegetables often eaten raw (tomato, cucumber, pepper, carrot, radish, lettuce) and how this might vary with growth in soil fertilized inorganically or with dairy or swine manure. Vegetables were sown into field plots immediately following fertilization and harvested when of marketable quality. Vegetable and soil samples were evaluated for viable antibiotic-resistant bacteria by plate count on Chromocult medium supplemented with antibiotics at clinical breakpoint concentrations. DNA was extracted from soil and vegetables and evaluated by PCR for the presence of 46 gene targets associated with plasmid incompatibility groups, integrons, or antibiotic resistance genes. Soil receiving manure was enriched in antibiotic-resistant bacteria and various antibiotic resistance determinants. There was no coherent corresponding increase in the abundance of antibiotic-resistant bacteria enumerated from any vegetable grown in manure-fertilized soil. Numerous antibiotic resistance determinants were detected in DNA extracted from vegetables grown in unmanured soil. A smaller number of determinants were additionally detected on vegetables grown only in manured and not in unmanured soil. Overall, consumption of raw vegetables represents a route of human exposure to antibiotic-resistant bacteria and resistance determinants naturally present in soil. However, the detection of some determinants on vegetables grown only in freshly manured soil reinforces the advisability of pretreating manure through composting or other stabilization processes or mandating offset times between manuring and harvesting vegetables for human consumption.

Cooperation, competition and antibiotic resistance in bacterial colonies.

PubMed

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

2018-06-01

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

Antimicrobial resistance patterns of colonizing Streptococcus pneumoniae among young child-mother pairs in the rural highlands of the Peruvian Andes

PubMed Central

Howard, Leigh; Edwards, Kathryn; Griffin, Marie; Gil, Ana; Minaya, Gina; Mercado, Erik; Ochoa, Theresa; Lanata, Claudio; Grijalva, Carlos G

2017-01-01

Abstract Background Despite widespread use of pneumococcal conjugate vaccines (PCVs), Streptococcus pneumoniae (pneumococcus) remains an important cause of pneumonia. Prior to widespread PCV use, we found a high prevalence of nasopharyngeal (NP) colonization with pneumococcus resistant to multiple antibiotic classes among young children in the rural highlands of Peru. We sought to confirm contemporary resistance profiles among young children, their mothers, and animal contacts in the post-PCV era. Methods We enrolled eligible members of Peruvian households whose children had participated in our previous study. Mothers were questioned about antibiotic use for themselves and their children age <3 years. NP samples were collected from children, mothers, and their animal contacts including cows, guinea pigs, and dogs, when available. Samples were cultured for pneumococcus using standard methods and routine disk antibiotic susceptibility testing was performed. Drinking water and milk samples were tested, when available, for the presence of β-lactam and tetracycline residues (IDEXX Β-Tetra testing kit; Westbrook, ME). Results Members of 47 households were enrolled, including 50 children and 47 mothers (3 sibling pairs). The median (IQR) age of children was 1.2 years (0.6-2.2) and number of household members was 5 (4-6). Sixteen of 50 (32%) children and 7/47 (15%) mothers had received antibiotics in the prior 6 months (Fig 1). Pneumococcus was detected in 31/50 (62%) children, 9/47 (19%) mothers, and 1/31 (3%) guinea pigs. Pneumococci were not detected in dogs (n = 29) or cows (n = 7). Resistance to multiple classes of antibiotics, including TMP-SMX, tetracyclines, and β-lactams, was common among children and adults (Fig 2). No antibiotic residues were detected in water (n = 41) or milk (n = 7) samples. Conclusion Pneumococcal colonization was common among young children, less prevalent among adults, and rare among animals. Resistance to macrolides and tetracyclines was common despite very little reported use of these antibiotics in people. Additional studies should evaluate whether this high prevalence of resistance is a result of local prescribing practices or unintentional environmental exposures. ADDIN EN.REFLIST Disclosures K. Edwards, Novartis: Grant Investigator, Research grant. M. Griffin, MedImmune: Grant Investigator, Grant recipient. C. Lanata, Takeda: Scientific Advisor, Consulting fee. C. G. Grijalva, Pfizer: Consultant, Consulting fee.

Study protocol for One Health data collections, analyses and intervention of the Sino-Swedish integrated multisectoral partnership for antibiotic resistance containment (IMPACT).

PubMed

Sun, Qiang; Wang, Yang; Hulth, Anette; Xiao, Yonghong; Nilsson, Lennart E; Li, Xuewen; Bi, Zhenwang; Liu, Yuqing; Yin, Hong; Luo, Yanbo; Nilsson, Maud; Sun, Chengtao; Zhu, Yiqing; Zheng, Beiwen; Chen, Baoli; Sun, Pan; Ding, Lilu; Xia, Xi; Ottoson, Jakob; Löfmark, Sonja; Dyar, Oliver James; Börjesson, Stefan; Lundborg, Cecilia Stalsby

2018-01-21

To effectively minimise the emergence and dissemination of antibiotic resistant bacteria, a holistic One Health approach is called for. The Sino-Swedish Integrated Multisectoral Partnership for Antibiotic Resistance Containment is a cross-sectoral and integrated project on antibiotic resistance, conducted in Shandong Province in China. This paper outlines the overall study protocol for the project. To our knowledge, this is the first research programme aiming to take a true holistic approach across multiple sectors simultaneously in China, and the first to incorporate both antibiotic use and infection prevention and control in addition to antibiotic resistance patterns. The project aims to address gaps in current knowledge and seeks to improve the situation through a system-wide intervention. By using a One Health approach we can address important research questions that individual discipline investigations are unable to. The results obtained should thus more closely reflect the world in which human health, animal health and the environment are inextricably and intimately interlinked. Both quantitative and qualitative studies are included for households from 12 villages, their surrounding environment and a tertiary care hospital in a nearby town. The studies include analyses of antibiotic consumption for humans and pigs; qualitative and quantitative data on perceptions, knowledge and attitudes; faecal carriage of extended spectrum β-lactamase and carbapenemase-producing Enterobacteriaceae from pigs and humans, and occurrence in household drinking water, surface water, waste water and clinical bacterial isolates from the hospital. Carriage of methicillin-resistant Staphylococcus aureus in humans, household pigs and clinical bacterial isolates is also investigated. Furthermore, potential inter-relationships between these sources are analysed. A multifaceted One Health intervention is designed and implemented in 6 of the 12 villages. Repeated and continuous data collections take place over 2 years, where the repeated data collection is performed after 1 year of intervention. Comparisons are made between intervention and control villages, before and after the intervention. Ethics approval was obtained from the first Affiliated Hospital, College of Medicine, Zhejiang University, China, reference number 2015#185 and 2015#283. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Knowledge and perceptions on antibiotic use and resistance among high school students and teachers in New Delhi, India: A qualitative study.

PubMed

Kotwani, Anita; Wattal, Chand; Joshi, P C; Holloway, Kathleen

2016-01-01

To explore the perceptions and knowledge of school teachers and students about antibiotic use, resistance, and suggestions for practical interventions for the rational use of antibiotics. Five focus group discussions (FGDs) with high school students (Class: 9-11) and five with teachers were conducted in two private and three public schools (one teacher and one student FGD per school) in five municipal wards of Delhi. Qualitative data on antibiotic knowledge, resistance, and behaviors with respect to antibiotics use were collected. There were 4-8 persons per teacher FGD and 15-20 persons per student FGD. FGDs were analyzed using "thematic analyses." Students had poor knowledge regarding antibiotics and antibiotic resistance, while only some teachers had a basic understanding. Four broad themes needing attention emerged: definition of antibiotic and antibiotic resistance, antibiotic use behavior, doctor-patient relationship, and interventional strategies suggested to curtail the misuse of antibiotics and to spread awareness. In order to tackle these problems, both groups suggested a multipronged approach including robust public awareness campaigns also involving schools, better doctor-patient relationships, and stronger regulations. Although students and teachers exhibited poor knowledge about antibiotic use and resistance, they were keen to learn about these issues. School education programs and public education could be used to shape correct perceptions about antibiotic use among all stakeholders including children. This may help in the containment of antibiotic resistance and thus preservation of antibiotics for future generations.

Antimicrobial Resistance: The Major Contribution of Poor Governance and Corruption to This Growing Problem

PubMed Central

Collignon, Peter; Athukorala, Prema-chandra; Senanayake, Sanjaya; Khan, Fahad

2015-01-01

Objectives To determine how important governmental, social, and economic factors are in driving antibiotic resistance compared to the factors usually considered the main driving factors—antibiotic usage and levels of economic development. Design A retrospective multivariate analysis of the variation of antibiotic resistance in Europe in terms of human antibiotic usage, private health care expenditure, tertiary education, the level of economic advancement (per capita GDP), and quality of governance (corruption). The model was estimated using a panel data set involving 7 common human bloodstream isolates and covering 28 European countries for the period 1998–2010. Results Only 28% of the total variation in antibiotic resistance among countries is attributable to variation in antibiotic usage. If time effects are included the explanatory power increases to 33%. However when the control of corruption indicator is included as an additional variable, 63% of the total variation in antibiotic resistance is now explained by the regression. The complete multivariate regression only accomplishes an additional 7% in terms of goodness of fit, indicating that corruption is the main socioeconomic factor that explains antibiotic resistance. The income level of a country appeared to have no effect on resistance rates in the multivariate analysis. The estimated impact of corruption was statistically significant (p< 0.01). The coefficient indicates that an improvement of one unit in the corruption indicator is associated with a reduction in antibiotic resistance by approximately 0.7 units. The estimated coefficient of private health expenditure showed that one unit reduction is associated with a 0.2 unit decrease in antibiotic resistance. Conclusions These findings support the hypothesis that poor governance and corruption contributes to levels of antibiotic resistance and correlate better than antibiotic usage volumes with resistance rates. We conclude that addressing corruption and improving governance will lead to a reduction in antibiotic resistance. PMID:25786027

DETECTION, RIBOTYPING AND ANTIMICROBIAL RESISTANCE PROPERTIES OF CLOSTRIDIUM DIFFICILE STRAINS ISOLATED FROM THE CASES OF DIARRHEA.

PubMed

Kouzegaran, Samaneh; Ganjifard, Mahmood; Tanha, Amir Saber

2016-10-01

Clostridium difficile is the most prevalent cause of antibiotic-associated infectious diarrhea al-around the world. Prevalence of virulent and resistant strains of Clostridium difficile is increasing now a day. The present investigation was carried out to study the prevalence, ribotyping and antibiotic resistance pattern of C. difficile isolated from diarrheic and non-diarrheic pediatrics. Four-hundred stool specimens were collected from the diarrheic and non-diarrheic pediatrics hospitalized due to the diseases other than diarrhea. Samples were cultured and their positive results were subjected to disk diffusion and PCR-based ribotyping. Thirty-five out of 400 (8.75%) samples were positive for C. difficile . Prevalence of C. difficile in diarrheic and non-diarrheic pediatrics were 11.25% and 4.16%, respectively. Male had the higher prevalence of bacteria than female ( P < 0.05). eight to twelve months old pediatrics were the most commonly infected group. R27 (14.28%), R1 (10.71%), R12 (7.14%), R13 (7.14%) and R18 (7.14%) were most commonly detected ribotypes. There were no positive results for studied ribotypes in non-diarrheic pediatrics. C. difficile strains had the highest levels of resistance against tetracycline (71.42%), erythromycin (57.14%), moxifloxacin (48.57%), metronidazole (28.57%) and clindamycin (22.85%) antibiotics. Prescription of antibiotics in diarrheic pediatrics, males and also 8-12 months old pediatrics should be done in a regular and cautious manner.

Interplay Between Antibiotic Resistance and Virulence During Disease Promoted by Multidrug-Resistant Bacteria

PubMed Central

Geisinger, Edward

2017-01-01

Abstract Diseases caused by antibiotic-resistant bacteria in hospitals are the outcome of complex relationships between several dynamic factors, including bacterial pathogenicity, the fitness costs of resistance in the human host, and selective forces resulting from interventions such as antibiotic therapy. The emergence and fate of mutations that drive antibiotic resistance are governed by these interactions. In this review, we will examine how different forms of antibiotic resistance modulate bacterial fitness and virulence potential, thus influencing the ability of pathogens to evolve in the context of nosocomial infections. We will focus on 3 important multidrug-resistant pathogens that are notoriously problematic in hospitals: Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus. An understanding of how antibiotic resistance mutations shape the pathobiology of multidrug-resistant infections has the potential to drive novel strategies that can control the development and spread of drug resistance. PMID:28375515

Genotypic Detection of Antibiotic Resistance in "Escherichia Coli.": A Classroom Exercise

ERIC Educational Resources Information Center

Longtin, Sarah; Guilfoile, Patrick; Asper, Andrea

2004-01-01

Bacterial antibiotic resistance remains a problem of clinical importance. Current microbiological methods for determining antibiotic resistance are based on culturing bacteria, and may require up to 48 hours to complete. Molecular methods are increasingly being developed to speed the identification of antibiotic resistance and to determine its…

Canadian physicians' knowledge and counseling practices related to antibiotic use and antimicrobial resistance: Two-cycle national survey.

PubMed

Smith, Courtney R; Pogany, Lisa; Foley, Simon; Wu, Jun; Timmerman, Karen; Gale-Rowe, Margaret; Demers, Alain

2017-12-01

To establish a baseline for physicians' knowledge of and counseling practices on the use of antibiotics and antimicrobial resistance (AMR), and to determine potential changes in these measures after the implementation of a national AMR awareness campaign. Cross-sectional design. Canada. A total of 1600 physicians. Physicians' knowledge of and counseling practices on antibiotic use and AMR at baseline and after implementation of the AMR awareness campaign. A total of 336 physicians responded to the first-cycle survey (before the campaign), and 351 physicians responded to the second-cycle survey (after the campaign). Overall, physicians' knowledge of appropriate antibiotic use and AMR was high and their counseling practices in relation to antibiotics were appropriate in both surveys. Counseling levels about topics related to infection prevention and control (eg, food handling, household hygiene) were slightly lower. Counseling levels were also lower for certain antibiotic-use practices (eg, proper disposal of antibiotics). In addition, physicians with less than 10 years of practice experience had significantly lower odds of counseling their patients on topics related to preventing antibiotic resistance and infection prevention than those with 15 or more years of practice experience (adjusted odds ratio = 0.27, 95% CI 0.10 to 0.74). Significantly more physicians from the second-cycle survey counseled patients on the appropriate disposal of antibiotics ( P = .03), as well as on some of the infection prevention topics (eg, using antibacterial hand soap [ P = .02] and cleaning supplies [ P = .01]). Most respondents in both surveys reported feeling confident with respect to counseling their patients on the appropriate use of antibiotics and AMR. Physicians' knowledge of and levels of counseling on the use of antibiotics and AMR were high and fairly stable in both survey results. This shows that Canadian physicians are demonstrating behaviour patterns of AMR stewardship. Existing gaps in counseling practices might be a result of physicians believing that pharmacists or nurses are addressing these issues with patients. Future national surveys conducted among pharmacists and nurses would contribute to the evidence base for AMR stewardship activities. Copyright© the College of Family Physicians of Canada.

Canadian physicians’ knowledge and counseling practices related to antibiotic use and antimicrobial resistance

PubMed Central

Smith, Courtney R.; Pogany, Lisa; Foley, Simon; Wu, Jun; Timmerman, Karen; Gale-Rowe, Margaret; Demers, Alain

2017-01-01

Abstract Objective To establish a baseline for physicians’ knowledge of and counseling practices on the use of antibiotics and antimicrobial resistance (AMR), and to determine potential changes in these measures after the implementation of a national AMR awareness campaign. Design Cross-sectional design. Setting Canada. Participants A total of 1600 physicians. Main outcome measures Physicians’ knowledge of and counseling practices on antibiotic use and AMR at baseline and after implementation of the AMR awareness campaign. Results A total of 336 physicians responded to the first-cycle survey (before the campaign), and 351 physicians responded to the second-cycle survey (after the campaign). Overall, physicians’ knowledge of appropriate antibiotic use and AMR was high and their counseling practices in relation to antibiotics were appropriate in both surveys. Counseling levels about topics related to infection prevention and control (eg, food handling, household hygiene) were slightly lower. Counseling levels were also lower for certain antibiotic-use practices (eg, proper disposal of antibiotics). In addition, physicians with less than 10 years of practice experience had significantly lower odds of counseling their patients on topics related to preventing antibiotic resistance and infection prevention than those with 15 or more years of practice experience (adjusted odds ratio = 0.27, 95% CI 0.10 to 0.74). Significantly more physicians from the second-cycle survey counseled patients on the appropriate disposal of antibiotics (P = .03), as well as on some of the infection prevention topics (eg, using antibacterial hand soap [P = .02] and cleaning supplies [P = .01]). Most respondents in both surveys reported feeling confident with respect to counseling their patients on the appropriate use of antibiotics and AMR. Conclusion Physicians’ knowledge of and levels of counseling on the use of antibiotics and AMR were high and fairly stable in both survey results. This shows that Canadian physicians are demonstrating behaviour patterns of AMR stewardship. Existing gaps in counseling practices might be a result of physicians believing that pharmacists or nurses are addressing these issues with patients. Future national surveys conducted among pharmacists and nurses would contribute to the evidence base for AMR stewardship activities. PMID:29237649

Research progress on distribution, migration, transformation of antibiotics and antibiotic resistance genes (ARGs) in aquatic environment.

PubMed

Shao, Sicheng; Hu, Yongyou; Cheng, Jianhua; Chen, Yuancai

2018-05-28

Antimicrobial and antibiotics resistance caused by misuse or overuse of antibiotics exposure is a growing and significant threat to global public health. The spread and horizontal transfer of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) by the selective pressure of antibiotics in an aquatic environment is a major public health issue. To develop a better understanding of potential ecological risks die to antibiotics and ARGs, this study mainly summarizes research progress about: (i) the occurrence, concentration, fate, and potential ecological effects of antibiotics and ARGs in various aquatic environments, (ii) the threat, spread, and horizontal gene transfer (HGT) of ARGs, and (iii) the relationship between antibiotics, ARGs, and ARB. Finally, this review also proposes future research direction on antibiotics and ARGs.

The Prehistory of Antibiotic Resistance.

PubMed

Perry, Julie; Waglechner, Nicholas; Wright, Gerard

2016-06-01

Antibiotic resistance is a global problem that is reaching crisis levels. The global collection of resistance genes in clinical and environmental samples is the antibiotic "resistome," and is subject to the selective pressure of human activity. The origin of many modern resistance genes in pathogens is likely environmental bacteria, including antibiotic producing organisms that have existed for millennia. Recent work has uncovered resistance in ancient permafrost, isolated caves, and in human specimens preserved for hundreds of years. Together with bioinformatic analyses on modern-day sequences, these studies predict an ancient origin of resistance that long precedes the use of antibiotics in the clinic. Understanding the history of antibiotic resistance is important in predicting its future evolution. Copyright © 2016 Cold Spring Harbor Laboratory Press; all rights reserved.

Current perspectives on the dynamics of antibiotic resistance in different reservoirs.

PubMed

Caniça, Manuela; Manageiro, Vera; Jones-Dias, Daniela; Clemente, Lurdes; Gomes-Neves, Eduarda; Poeta, Patrícia; Dias, Elsa; Ferreira, Eugénia

2015-09-01

Antibiotic resistance consists of a dynamic web. In this review, we describe the path by which different antibiotic residues and antibiotic resistance genes disseminate among relevant reservoirs (human, animal, and environmental settings), evaluating how these events contribute to the current scenario of antibiotic resistance. The relationship between the spread of resistance and the contribution of different genetic elements and events is revisited, exploring examples of the processes by which successful mobile resistance genes spread across different niches. The importance of classic and next generation molecular approaches, as well as action plans and policies which might aid in the fight against antibiotic resistance, are also reviewed. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Effects of temperature and antibiotics on persistence of antibiotic-resistant bacteria and antibiotic resistance genes in poultry litter

USDA-ARS?s Scientific Manuscript database

The effect of low, residual concentrations of antibiotics in manure and other environmental matrices is not well understood. It has been hypothesized that antibiotic concentrations below clinical MIC (minimal inhibitory concentrations) are still capable of selecting for resistance. The objective of ...

Evaluation of new antimicrobials for the hospital formulary. Policies restricting antibiotic use in hospitals.

PubMed

Pujol, Miquel; Delgado, Olga; Puigventós, Francesc; Corzo, Juan E; Cercenado, Emilia; Martínez, José Antonio

2013-09-01

In Spain, the inclusion of new antibiotics in hospital formularies is performed by the Infection Policy Committee or the Pharmacy and Therapeutic Committee, although now the decision is moving to a regional level. Criteria for the evaluation of new drugs include efficacy, safety and cost. For antimicrobial drugs evaluation it is necessary to consider local sensibility and impact in bacterial resistance to determinate the therapeutic positioning. There is compelling evidence that the use of antibiotics is associated with increasing bacterial resistance, and a great number of antibiotics are used incorrectly. In order to decrease the inappropriate use of antibiotics, several approaches have been proposed. Limiting the use of antimicrobials through formulary restrictions, often aimed at drugs with a specific resistance profile, shows benefits in improving antimicrobial susceptibilities and decreasing colonization by drug-resistant organisms. However, the restriction of one agent may result in the increased utilization of other agents. By using antibiotic cycling, the amount of antibiotics is maintained below the threshold where bacterial resistance develops, thus preserving highly efficient antibiotics. Unfortunately, cumulative evidence to date suggests that antibiotic cycling has limited efficacy in preventing antibiotic resistance. Finally, although there is still little clinical evidence available on antibiotic heterogeneity, the use of most of the existing antimicrobial classes could limit the emergence of resistance. This review summarizes information regarding antibiotic evaluation and available restrictive strategies to limit the use of antibiotics at hospitals with the aim of curtailing increasing antibiotic resistance. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Antimicrobial resistance and virulence profile of enterococci isolated from poultry and cattle sources in Nigeria.

PubMed

Ngbede, Emmanuel Ochefije; Raji, Mashood Abiola; Kwanashie, Clara Nna; Kwaga, Jacob Kwada Paghi

2017-03-01

This study investigated the occurrence, antimicrobial resistance and virulence of Enterococcus from poultry and cattle farms. Three hundred and ninety samples: cloacal/rectal swabs (n = 260) and manure (n = 130] were processed for recovery of Enterococcus species. Standard bacteriological methods were used to isolate, identify and characterize Enterococcus species for antimicrobial susceptibility and expression of virulence traits. Detection of antibiotic resistance and virulence genes was carried out by polymerase chain reaction. Enterococcus was recovered from 167 (42.8%) of the 390 samples tested with a predominance of Enterococcus faecium (27.7%). Other species detected were Enterococcus gallinarum, Enterococcus faecalis, Enterococcus hirae, Enterococcus raffinosus, Enterococcus avium, Enterococcus casseliflavus, Enterococcus mundtii and Enterococcus durans. All the isolates tested were susceptible to vancomycin, but resistance to tetracycline, erythromycin, ampicillin and gentamicin was also observed among 61.0, 61.0, 45.1 and 32.7% of the isolates, respectively. Sixty (53.1%) of the isolates were multidrug resistant presenting as 24 different resistance patterns with resistance to gentamicin-erythromycin-streptomycin-tetracycline (CN-ERY-STR-TET) being the most common (n = 11) pattern. In addition to expression of virulence traits (haemolysin, gelatinase, biofilm production), antibiotic resistance (tetK, tetL, tetM, tetO and ermB) and virulence (asa1, gelE, cylA) genes were detected among the isolates. Also, in vitro transfer of resistance determinants was observed among 75% of the isolates tested. Our data revealed poultry, cattle and manure in this area are hosts to varying Enterococcus species harbouring virulence and resistance determinants that can be transferred to other organisms and also are important for causing nosocomial infection.

[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.

Antibiotic Resistance and Antibiotic Resistance Genes in Escherichia coli Isolates from Hospital Wastewater in Vietnam

PubMed Central

Lan, Pham Thi; Chuc, Nguyen Thi Kim; Hoa, Nguyen Quynh; Nhung, Pham Hong; Thoa, Nguyen Thi Minh; Diwan, Vishal; Tamhankar, Ashok J.; Stålsby Lundborg, Cecilia

2017-01-01

The environmental spread of antibiotic-resistant bacteria has been recognised as a growing public health threat for which hospitals play a significant role. The aims of this study were to investigate the prevalence of antibiotic resistance and antibiotic resistance genes (ARGs) in Escherichia coli isolates from hospital wastewater in Vietnam. Wastewater samples before and after treatment were collected using continuous sampling every month over a year. Standard disk diffusion and E-test were used for antibiotic susceptibility testing. Extended-spectrum beta-lactamase (ESBL) production was tested using combined disk diffusion. ARGs were detected by polymerase chain reactions. Resistance to at least one antibiotic was detected in 83% of isolates; multidrug resistance was found in 32%. The highest resistance prevalence was found for co-trimoxazole (70%) and the lowest for imipenem (1%). Forty-three percent of isolates were ESBL-producing, with the blaTEM gene being more common than blaCTX-M. Co-harbouring of the blaCTX-M, blaTEM and qepA genes was found in 46% of isolates resistant to ciprofloxacin. The large presence of antibiotic-resistant E. coli isolates combined with ARGs in hospital wastewater, even post-treatment, poses a threat to public health. It highlights the need to develop effective processes for hospital wastewater treatment plants to eliminate antibiotic resistant bacteria and ARGs. PMID:28661465

Lytic phages obscure the cost of antibiotic resistance in Escherichia coli.

PubMed

Tazzyman, Samuel J; Hall, Alex R

2015-03-17

The long-term persistence of antibiotic-resistant bacteria depends on their fitness relative to other genotypes in the absence of drugs. Outside the laboratory, viruses that parasitize bacteria (phages) are ubiquitous, but costs of antibiotic resistance are typically studied in phage-free experimental conditions. We used a mathematical model and experiments with Escherichia coli to show that lytic phages strongly affect the incidence of antibiotic resistance in drug-free conditions. Under phage parasitism, the likelihood that antibiotic-resistant genetic backgrounds spread depends on their initial frequency, mutation rate and intrinsic growth rate relative to drug-susceptible genotypes, because these parameters determine relative rates of phage-resistance evolution on different genetic backgrounds. Moreover, the average cost of antibiotic resistance in terms of intrinsic growth in the antibiotic-free experimental environment was small relative to the benefits of an increased mutation rate in the presence of phages. This is consistent with our theoretical work indicating that, under phage selection, typical costs of antibiotic resistance can be outweighed by realistic increases in mutability if drug resistance and hypermutability are genetically linked, as is frequently observed in clinical isolates. This suggests the long-term distribution of antibiotic resistance depends on the relative rates at which different lineages adapt to other types of selection, which in the case of phage parasitism is probably extremely common, as well as costs of resistance inferred by classical in vitro methods.

Lytic phages obscure the cost of antibiotic resistance in Escherichia coli

PubMed Central

Tazzyman, Samuel J; Hall, Alex R

2015-01-01

The long-term persistence of antibiotic-resistant bacteria depends on their fitness relative to other genotypes in the absence of drugs. Outside the laboratory, viruses that parasitize bacteria (phages) are ubiquitous, but costs of antibiotic resistance are typically studied in phage-free experimental conditions. We used a mathematical model and experiments with Escherichia coli to show that lytic phages strongly affect the incidence of antibiotic resistance in drug-free conditions. Under phage parasitism, the likelihood that antibiotic-resistant genetic backgrounds spread depends on their initial frequency, mutation rate and intrinsic growth rate relative to drug-susceptible genotypes, because these parameters determine relative rates of phage-resistance evolution on different genetic backgrounds. Moreover, the average cost of antibiotic resistance in terms of intrinsic growth in the antibiotic-free experimental environment was small relative to the benefits of an increased mutation rate in the presence of phages. This is consistent with our theoretical work indicating that, under phage selection, typical costs of antibiotic resistance can be outweighed by realistic increases in mutability if drug resistance and hypermutability are genetically linked, as is frequently observed in clinical isolates. This suggests the long-term distribution of antibiotic resistance depends on the relative rates at which different lineages adapt to other types of selection, which in the case of phage parasitism is probably extremely common, as well as costs of resistance inferred by classical in vitro methods. PMID:25268496

Antibiotic Resistance and Antibiotic Resistance Genes in Escherichia coli Isolates from Hospital Wastewater in Vietnam.

PubMed

Lien, La Thi Quynh; Lan, Pham Thi; Chuc, Nguyen Thi Kim; Hoa, Nguyen Quynh; Nhung, Pham Hong; Thoa, Nguyen Thi Minh; Diwan, Vishal; Tamhankar, Ashok J; Stålsby Lundborg, Cecilia

2017-06-29

The environmental spread of antibiotic-resistant bacteria has been recognised as a growing public health threat for which hospitals play a significant role. The aims of this study were to investigate the prevalence of antibiotic resistance and antibiotic resistance genes (ARGs) in Escherichia coli isolates from hospital wastewater in Vietnam. Wastewater samples before and after treatment were collected using continuous sampling every month over a year. Standard disk diffusion and E-test were used for antibiotic susceptibility testing. Extended-spectrum beta-lactamase (ESBL) production was tested using combined disk diffusion. ARGs were detected by polymerase chain reactions. Resistance to at least one antibiotic was detected in 83% of isolates; multidrug resistance was found in 32%. The highest resistance prevalence was found for co-trimoxazole (70%) and the lowest for imipenem (1%). Forty-three percent of isolates were ESBL-producing, with the bla TEM gene being more common than bla CTX-M . Co-harbouring of the bla CTX-M , bla TEM and qepA genes was found in 46% of isolates resistant to ciprofloxacin. The large presence of antibiotic-resistant E. coli isolates combined with ARGs in hospital wastewater, even post-treatment, poses a threat to public health. It highlights the need to develop effective processes for hospital wastewater treatment plants to eliminate antibiotic resistant bacteria and ARGs.

Occurrence and Distribution of Antibiotic-resistant Bacteria and Transfer of Resistance Genes in Lake Taihu

PubMed Central

Yin, Qian; Yue, Dongmei; Peng, Yuke; Liu, Ying; Xiao, Lin

2013-01-01

The overuse of antibiotics has accelerated antibiotic resistance in the natural environment, especially fresh water, generating a potential risk for public health around the world. In this study, antibiotic resistance in Lake Taihu was investigated and this was the first thorough data obtained through culture-dependent methods. High percentages of resistance to streptomycin and ampicillin among bacterial isolates were detected, followed by tetracycline and chloramphenicol. Especially high levels of ampicillin resistance in the western and northern regions were illustrated. Bacterial identification of the isolates selected for further study indicated the prevalence of some opportunistic pathogens and 62.0% of the 78 isolates exhibited multiple antibiotic resistance. The presence of ESBLs genes was in the following sequence: blaTEM > blaSHV > blaCTMX and 38.5% of the isolates had a class I integrase gene. Of all tested strains, 80.8% were able to transfer antibiotic resistance through conjugation. We also concluded that some new families of human-associated ESBLs and AmpC genes can be found in natural environmental isolates. The prevalence of antibiotic resistance and the dissemination of transferable antibiotic resistance in bacterial isolates (especially in opportunistic pathogens) was alarming and clearly indicated the urgency of realizing the health risks of antibiotic resistance to human and animal populations who are dependent on Lake Taihu for water consumption. PMID:24240317

Antimicrobial activity of the ornamental species Salvia corrugata, a potential new crop for extractive purposes.

PubMed

Bisio, Angela; Romussi, Giovanni; Russo, Eleonora; Cafaggi, Sergio; Schito, Anna Maria; Repetto, Barbara; De Tommasi, Nunziatina

2008-11-26

As a part of our search for biologically active compounds from cultivated Salvia spp. we investigated Salvia corrugata Vahl. The activity of two isolated icetaxane diterpene quinones, fruticuline A and demethylfruticuline A, was assessed against 46 bacterial pathogens, mostly resistant to several primary antibiotics. The MIC for all the inhibited Gram-positive pathogens tested showed a very narrow distribution and ranged from 32 to 64 mg/L, regardless of their resistance patterns to other antibiotics. Demethylfruticuline A was shown to be highly bactericidal (>3 log(10) CFU decrease within 24 h) against Staphylococcus aureus and S. epidermidis and bacteriostatic against Enterococcus faecalis and E. faecium. Fruticuline A manifested bacteriostatic activity against all tested strains. S. corrugata can be viewed as an interesting source for these diterpenes, which, if well tolerated in vivo, may represent new medical agents useful for the treatment of serious infections caused by resistant Gram-positive pathogens.

The Comprehensive Antibiotic Resistance Database

PubMed Central

McArthur, Andrew G.; Waglechner, Nicholas; Nizam, Fazmin; Yan, Austin; Azad, Marisa A.; Baylay, Alison J.; Bhullar, Kirandeep; Canova, Marc J.; De Pascale, Gianfranco; Ejim, Linda; Kalan, Lindsay; King, Andrew M.; Koteva, Kalinka; Morar, Mariya; Mulvey, Michael R.; O'Brien, Jonathan S.; Pawlowski, Andrew C.; Piddock, Laura J. V.; Spanogiannopoulos, Peter; Sutherland, Arlene D.; Tang, Irene; Taylor, Patricia L.; Thaker, Maulik; Wang, Wenliang; Yan, Marie; Yu, Tennison

2013-01-01

The field of antibiotic drug discovery and the monitoring of new antibiotic resistance elements have yet to fully exploit the power of the genome revolution. Despite the fact that the first genomes sequenced of free living organisms were those of bacteria, there have been few specialized bioinformatic tools developed to mine the growing amount of genomic data associated with pathogens. In particular, there are few tools to study the genetics and genomics of antibiotic resistance and how it impacts bacterial populations, ecology, and the clinic. We have initiated development of such tools in the form of the Comprehensive Antibiotic Research Database (CARD; http://arpcard.mcmaster.ca). The CARD integrates disparate molecular and sequence data, provides a unique organizing principle in the form of the Antibiotic Resistance Ontology (ARO), and can quickly identify putative antibiotic resistance genes in new unannotated genome sequences. This unique platform provides an informatic tool that bridges antibiotic resistance concerns in health care, agriculture, and the environment. PMID:23650175

Country-specific antibiotic use practices impact the human gut resistome

PubMed Central

Forslund, Kristoffer; Sunagawa, Shinichi; Kultima, Jens Roat; Mende, Daniel R.; Arumugam, Manimozhiyan; Typas, Athanasios; Bork, Peer

2013-01-01

Despite increasing concerns over inappropriate use of antibiotics in medicine and food production, population-level resistance transfer into the human gut microbiota has not been demonstrated beyond individual case studies. To determine the “antibiotic resistance potential” for entire microbial communities, we employ metagenomic data and quantify the totality of known resistance genes in each community (its resistome) for 68 classes and subclasses of antibiotics. In 252 fecal metagenomes from three countries, we show that the most abundant resistance determinants are those for antibiotics also used in animals and for antibiotics that have been available longer. Resistance genes are also more abundant in samples from Spain, Italy, and France than from Denmark, the United States, or Japan. Where comparable country-level data on antibiotic use in both humans and animals are available, differences in these statistics match the observed resistance potential differences. The results are robust over time as the antibiotic resistance determinants of individuals persist in the human gut flora for at least a year. PMID:23568836

Non-antibiotic antimicrobial triclosan induces multiple antibiotic resistance through genetic mutation.

PubMed

Lu, Ji; Jin, Min; Nguyen, Son Hoang; Mao, Likai; Li, Jie; Coin, Lachlan J M; Yuan, Zhiguo; Guo, Jianhua

2018-06-11

Antibiotic resistance poses a major threat to public health. Overuse and misuse of antibiotics are generally recognized as the key factors contributing to antibiotic resistance. However, whether non-antibiotic, anti-microbial (NAAM) chemicals can directly induce antibiotic resistance is unclear. We aim to investigate whether the exposure to a NAAM chemical triclosan (TCS) has an impact on inducing antibiotic resistance on Escherichia coli. Here, we report that at a concentration of 0.2 mg/L TCS induces multi-drug resistance in wild-type Escherichia coli after 30-day TCS exposure. The oxidative stress induced by TCS caused genetic mutations in genes such as fabI, frdD, marR, acrR and soxR, and subsequent up-regulation of the transcription of genes encoding beta-lactamases and multi-drug efflux pumps, together with down-regulation of genes related to membrane permeability. The findings advance our understanding of the potential role of NAAM chemicals in the dissemination of antibiotic resistance in microbes, and highlight the need for controlling biocide applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

In vitro activity of monoclonal and recombinant yeast killer toxin-like antibodies against antibiotic-resistant gram-positive cocci.

PubMed Central

Conti, S.; Magliani, W.; Arseni, S.; Dieci, E.; Frazzi, R.; Salati, A.; Varaldo, P. E.; Polonelli, L.

2000-01-01

BACKGROUND: Monoclonal (mAbKT) and recombinant single-chain (scFvKT) anti-idiotypic antibodies were produced to represent the internal image of a yeast killer toxin (KT) characterized by a wide spectrum of antimicrobial activity, including gram-positive cocci. Pathogenic eukaryotic and prokaryotic microorganisms, such as Candida albicans, Pneumocystis carinii, and a multidrug-resistant strain of Mycobacterium tuberculosis, presenting specific, although yet undefined, KT-cell wall receptors (KTR), have proven to be killed in vitro by mAbKT and scFvKT. mAbKT and scFvKT exert a therapeutic effect in vivo in experimental models of candidiasis and pneumocystosis by mimicking the functional activity of protective antibodies naturally produced in humans against KTR of infecting microorganisms. The swelling tide of concern over increasing bacterial resistance to antibiotic drugs gives the impetus to develop new therapeutic compounds against microbial threat. Thus, the in vitro bactericidal activity of mAbKT and scFvKT against gram-positive, drug-resistant cocci of major epidemiological interest was investigated. MATERIALS AND METHODS: mAbKT and scFvKT generated by hybridoma and DNA recombinant technology from the spleen lymphocytes of mice immunized with a KT-neutralizing monoclonal antibody (mAb KT4) were used in a conventional colony forming unit (CFU) assay to determine, from a qualitative point of view, their bactericidal activity against Staphylococcus aureus, S. haemolyticus, Enterococcus faecalis, E. faecium, and Streptococcus pneumoniae strains. These bacterial strains are characterized by different patterns of resistance to antibiotics, including methicillin, vancomycin, and penicillin. RESULTS: According to the experimental conditions adopted, no bacterial isolate proved to be resistant to the activity of mAbKT and scFvKT. CONCLUSIONS: scFvKT exerted a microbicidal activity against multidrug resistant bacteria, which may represent the basis for the drug modeling of new antibiotics with broad antibacterial spectra to tackle the emergence of microbial resistance. PMID:10997342

Genome-wide analysis captures the determinants of the antibiotic cross-resistance interaction network

PubMed Central

Lázár, Viktória; Nagy, István; Spohn, Réka; Csörgő, Bálint; Györkei, Ádám; Nyerges, Ákos; Horváth, Balázs; Vörös, Andrea; Busa-Fekete, Róbert; Hrtyan, Mónika; Bogos, Balázs; Méhi, Orsolya; Fekete, Gergely; Szappanos, Balázs; Kégl, Balázs; Papp, Balázs; Pál, Csaba

2014-01-01

Understanding how evolution of antimicrobial resistance increases resistance to other drugs is a challenge of profound importance. By combining experimental evolution and genome sequencing of 63 laboratory-evolved lines, we charted a map of cross-resistance interactions between antibiotics in Escherichia coli, and explored the driving evolutionary principles. Here, we show that (1) convergent molecular evolution is prevalent across antibiotic treatments, (2) resistance conferring mutations simultaneously enhance sensitivity to many other drugs and (3) 27% of the accumulated mutations generate proteins with compromised activities, suggesting that antibiotic adaptation can partly be achieved without gain of novel function. By using knowledge on antibiotic properties, we examined the determinants of cross-resistance and identified chemogenomic profile similarity between antibiotics as the strongest predictor. In contrast, cross-resistance between two antibiotics is independent of whether they show synergistic effects in combination. These results have important implications on the development of novel antimicrobial strategies. PMID:25000950

A potent synthetic inorganic antibiotic with activity against drug-resistant pathogens.

PubMed

Hubick, Shelby; Jayaraman, Arumugam; McKeen, Alexander; Reid, Shelby; Alcorn, Jane; Stavrinides, John; Sterenberg, Brian T

2017-02-06

The acronymously named "ESKAPE" pathogens represent a group of bacteria that continue to pose a serious threat to human health, not only due to their propensity for repeated emergence, but also due to their ability to "eskape" antibiotic treatment. The evolution of multi-drug resistance in these pathogens alone has greatly outpaced the development of new therapeutics, necessitating an alternative strategy for antibiotic development that considers the evolutionary mechanisms driving antibiotic resistance. In this study, we synthesize a novel inorganic antibiotic, phosphopyricin, which has antibiotic activity against the Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE). We show that this potent antibiotic is bactericidal, and exhibits low toxicity in an acute dose assay in mice. As a synthetic compound that does not occur naturally, phosphopyricin would be evolutionarily foreign to microbes, thereby slowing the evolution of resistance. In addition, it loses antibiotic activity upon exposure to light, meaning that the active antibiotic will not accumulate in the general environment where strong selective pressures imposed by antibiotic residuals are known to accelerate resistance. Phosphopyricin represents an innovation in antimicrobials, having a synthetic core, and a photosensitive chemical architecture that would reduce accumulation in the environment.

A potent synthetic inorganic antibiotic with activity against drug-resistant pathogens

PubMed Central

Hubick, Shelby; Jayaraman, Arumugam; McKeen, Alexander; Reid, Shelby; Alcorn, Jane; Stavrinides, John; Sterenberg, Brian T.

2017-01-01

The acronymously named “ESKAPE” pathogens represent a group of bacteria that continue to pose a serious threat to human health, not only due to their propensity for repeated emergence, but also due to their ability to “eskape” antibiotic treatment12. The evolution of multi-drug resistance in these pathogens alone has greatly outpaced the development of new therapeutics, necessitating an alternative strategy for antibiotic development that considers the evolutionary mechanisms driving antibiotic resistance. In this study, we synthesize a novel inorganic antibiotic, phosphopyricin, which has antibiotic activity against the Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE). We show that this potent antibiotic is bactericidal, and exhibits low toxicity in an acute dose assay in mice. As a synthetic compound that does not occur naturally, phosphopyricin would be evolutionarily foreign to microbes, thereby slowing the evolution of resistance. In addition, it loses antibiotic activity upon exposure to light, meaning that the active antibiotic will not accumulate in the general environment where strong selective pressures imposed by antibiotic residuals are known to accelerate resistance. Phosphopyricin represents an innovation in antimicrobials, having a synthetic core, and a photosensitive chemical architecture that would reduce accumulation in the environment. PMID:28165020

The Culturable Soil Antibiotic Resistome: A Community of Multi-Drug Resistant Bacteria

PubMed Central

Walsh, Fiona; Duffy, Brion

2013-01-01

Understanding the soil bacterial resistome is essential to understanding the evolution and development of antibiotic resistance, and its spread between species and biomes. We have identified and characterized multi-drug resistance (MDR) mechanisms in the culturable soil antibiotic resistome and linked the resistance profiles to bacterial species. We isolated 412 antibiotic resistant bacteria from agricultural, urban and pristine soils. All isolates were multi-drug resistant, of which greater than 80% were resistant to 16–23 antibiotics, comprising almost all classes of antibiotic. The mobile resistance genes investigated, (ESBL, bla NDM-1, and plasmid mediated quinolone resistance (PMQR) resistance genes) were not responsible for the respective resistance phenotypes nor were they present in the extracted soil DNA. Efflux was demonstrated to play an important role in MDR and many resistance phenotypes. Clinically relevant Burkholderia species are intrinsically resistant to ciprofloxacin but the soil Burkholderia species were not intrinsically resistant to ciprofloxacin. Using a phenotypic enzyme assay we identified the antibiotic specific inactivation of trimethoprim in 21 bacteria from different soils. The results of this study identified the importance of the efflux mechanism in the soil resistome and variations between the intrinsic resistance profiles of clinical and soil bacteria of the same family. PMID:23776501

Antibiotic resistance in hospitals: a ward-specific random effect model in a low antibiotic consumption environment.

PubMed

Aldrin, Magne; Raastad, Ragnhild; Tvete, Ingunn Fride; Berild, Dag; Frigessi, Arnoldo; Leegaard, Truls; Monnet, Dominique L; Walberg, Mette; Müller, Fredrik

2013-04-15

Association between previous antibiotic use and emergence of antibiotic resistance has been reported for several microorganisms. The relationship has been extensively studied, and although the causes of antibiotic resistance are multi-factorial, clear evidence of antibiotic use as a major risk factor exists. Most studies are carried out in countries with high consumption of antibiotics and corresponding high levels of antibiotic resistance, and currently, little is known whether and at what level the associations are detectable in a low antibiotic consumption environment. We conduct an ecological, retrospective study aimed at determining the impact of antibiotic consumption on antibiotic-resistant Pseudomonas aeruginosa in three hospitals in Norway, a country with low levels of antibiotic use. We construct a sophisticated statistical model to capture such low signals. To reduce noise, we conduct our study at hospital ward level. We propose a random effect Poisson or binomial regression model, with a reparametrisation that allows us to reduce the number of parameters. Inference is likelihood based. Through scenario simulation, we study the potential effects of reduced or increased antibiotic use. Results clearly indicate that the effects of consumption on resistance are present under conditions with relatively low use of antibiotic agents. This strengthens the recommendation on prudent use of antibiotics, even when consumption is relatively low. Copyright © 2012 John Wiley & Sons, Ltd.

Persistence of transferable extended-spectrum-β-lactamase resistance in the absence of antibiotic pressure.

PubMed

Cottell, Jennifer L; Webber, Mark A; Piddock, Laura J V

2012-09-01

The treatment of infections caused by antibiotic-resistant bacteria is one of the great challenges faced by clinicians in the 21st century. Antibiotic resistance genes are often transferred between bacteria by mobile genetic vectors called plasmids. It is commonly believed that removal of antibiotic pressure will reduce the numbers of antibiotic-resistant bacteria due to the perception that carriage of resistance imposes a fitness cost on the bacterium. This study investigated the ability of the plasmid pCT, a globally distributed plasmid that carries an extended-spectrum-β-lactamase (ESBL) resistance gene (bla(CTX-M-14)), to persist and disseminate in the absence of antibiotic pressure. We investigated key attributes in plasmid success, including conjugation frequencies, bacterial-host growth rates, ability to cause infection, and impact on the fitness of host strains. We also determined the contribution of the bla(CTX-M-14) gene itself to the biology of the plasmid and host bacterium. Carriage of pCT was found to impose no detectable fitness cost on various bacterial hosts. An absence of antibiotic pressure and inactivation of the antibiotic resistance gene also had no effect on plasmid persistence, conjugation frequency, or bacterial-host biology. In conclusion, plasmids such as pCT have evolved to impose little impact on host strains. Therefore, the persistence of antibiotic resistance genes and their vectors is to be expected in the absence of antibiotic selective pressure regardless of antibiotic stewardship. Other means to reduce plasmid stability are needed to prevent the persistence of these vectors and the antibiotic resistance genes they carry.

Genotypic and phenotypic characterization of invasive neonatal Escherichia coli clinical isolates.

PubMed

Shakir, Salika Mehreen; Goldbeck, Jessica Marie; Robison, Denise; Eckerd, Annette Marie; Chavez-Bueno, Susana

2014-11-01

The objective of this study was to describe the clinical characteristics of neonates with Escherichia coli bacteremia and the antibiotic resistance pattern of the bacterial isolates. We assessed the isolates' genetic relatedness and virulence phenotypic characteristics in vitro. A total of 24 neonates with E. coli bacteremia were identified prospectively in a tertiary-care hospital. Clinical and antibiotic resistance data were investigated. The E. coli isolates were analyzed by multilocus sequence typing (MLST); the presence of the K1 capsule and their ability to invade intestinal epithelial cells were also assessed. Most newborns were very low birth weight infants. Overall, 75% of the isolates were ampicillin resistant and 17% were gentamicin and tobramycin nonsusceptible. MLST determined sequence types 95 and 131 (ST95 and ST131) predominated, with ST131 becoming significantly more prevalent recently. The K1 capsule was present in 50% of the isolates. ST131 isolates and those producing bacteremia in newborns younger than 7 days showed a highly invasive phenotype. Resistance to antibiotics currently used empirically to treat newborns is present in bacteremia-producing E. coli. Clonal spread among newborns of multidrug-resistant E. coli is possible; therefore, continued surveillance is needed. Identification of additional virulence factors associated with increased invasion in neonatal E. coli strains is important and further studies are warranted. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Antibiotic Resistance in Plant-Pathogenic Bacteria.

PubMed

Sundin, George W; Wang, Nian

2018-06-01

Antibiotics have been used for the management of relatively few bacterial plant diseases and are largely restricted to high-value fruit crops because of the expense involved. Antibiotic resistance in plant-pathogenic bacteria has become a problem in pathosystems where these antibiotics have been used for many years. Where the genetic basis for resistance has been examined, antibiotic resistance in plant pathogens has most often evolved through the acquisition of a resistance determinant via horizontal gene transfer. For example, the strAB streptomycin-resistance genes occur in Erwinia amylovora, Pseudomonas syringae, and Xanthomonas campestris, and these genes have presumably been acquired from nonpathogenic epiphytic bacteria colocated on plant hosts under antibiotic selection. We currently lack knowledge of the effect of the microbiome of commensal organisms on the potential of plant pathogens to evolve antibiotic resistance. Such knowledge is critical to the development of robust resistance management strategies to ensure the safe and effective continued use of antibiotics in the management of critically important diseases. Expected final online publication date for the Annual Review of Phytopathology Volume 56 is August 25, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Molecular typing of antibiotic-resistant Staphylococcus aureus in Nigeria.

PubMed

O'Malley, S M; Emele, F E; Nwaokorie, F O; Idika, N; Umeizudike, A K; Emeka-Nwabunnia, I; Hanson, B M; Nair, R; Wardyn, S E; Smith, T C

2015-01-01

Antibiotic-resistant Staphylococcus aureus including methicillin-resistant strains (MRSA) are a major concern in densely populated urban areas. Initial studies of S. aureus in Nigeria indicated existence of antibiotic-resistant S. aureus strains in clinical and community settings. 73 biological samples (40 throat, 23 nasal, 10 wound) were collected from patients and healthcare workers in three populations in Nigeria: Lagos University Teaching Hospital, Nigerian Institute of Medical Research, and Owerri General Hospital. S. aureus was isolated from 38 of 73 samples (52%). Of the 38 S. aureus samples, 9 (24%) carried the Panton-Valentine leukocidin gene (PVL) while 16 (42%) possessed methicillin resistance genes (mecA). Antibiotic susceptibility profiles indicated resistance to several broad-spectrum antibiotics. Antibiotic-resistant S. aureus isolates were recovered from clinical and community settings in Nigeria. Insight about S. aureus in Nigeria may be used to improve antibiotic prescription methods and minimize the spread of antibiotic-resistant organisms in highly populated urban communities similar to Lagos, Nigeria. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Quantifying Attachment and Antibiotic Resistance of from Conventional and Organic Swine Manure.

PubMed

Zwonitzer, Martha R; Soupir, Michelle L; Jarboe, Laura R; Smith, Douglas R

2016-03-01

Broad-spectrum antibiotics are often administered to swine, contributing to the occurrence of antibiotic-resistant bacteria in their manure. During land application, the bacteria in swine manure preferentially attach to particles in the soil, affecting their transport in overland flow. However, a quantitative understanding of these attachment mechanisms is lacking, and their relationship to antibiotic resistance is unknown. The objective of this study is to examine the relationships between antibiotic resistance and attachment to very fine silica sand in collected from swine manure. A total of 556 isolates were collected from six farms, two organic and four conventional (antibiotics fed prophylactically). Antibiotic resistance was quantified using 13 antibiotics at three minimum inhibitory concentrations: resistant, intermediate, and susceptible. Of the 556 isolates used in the antibiotic resistance assays, 491 were subjected to an attachment assay. Results show that isolates from conventional systems were significantly more resistant to amoxicillin, ampicillin, chlortetracycline, erythromycin, kanamycin, neomycin, streptomycin, tetracycline, and tylosin ( < 0.001). Results also indicate that isolated from conventional systems attached to very fine silica sand at significantly higher levels than those from organic systems ( < 0.001). Statistical analysis showed that a significant relationship did not exist between antibiotic resistance levels and attachment in from conventional systems but did for organic systems ( < 0.001). Better quantification of these relationships is critical to understanding the behavior of in the environment and preventing exposure of human populations to antibiotic-resistant bacteria. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Causative pathogens and antibiotic resistance in children hospitalized for urinary tract infection.

PubMed

Koçak, Mesut; Büyükkaragöz, Bahar; Çelebi Tayfur, Asli; Çaltik, Aysun; Köksoy, Adem Yasin; Çizmeci, Zeynep; Günbey, Sacit

2016-06-01

Urinary tract infections (UTI) are one of the most common bacterial infections in children and a major cause of hospitalization. In this study we investigated the clinical characteristics, causative uropathogens; their antibiotic susceptibility and resistance patterns, treatment modalities and efficacy in children hospitalized for UTI in a tertiary care setting. Patients hospitalized for an upper UTI between March 2009 and July 2014 were enrolled. The urine culture-antibiogram results and accompanying urinary tract abnormalities were recorded retrospectively. A total of 142 patients (104 girls, 73.2%; 38 boys, 26.8%) were enrolled. Mean patient age was 32.6 ± 4.1 months. History of recurrent UTI was present in 45.8% (n = 65), with prior hospitalization in 12.0% (n = 17). Frequency of vesicoureteral reflux was 18.3% (n = 26). Gram-negative enteric microorganisms yielded growth in all culture-positive UTI and the most common microorganism was Escherichia coli (n = 114, 80.3%). Extended spectrum beta-lactamase-producing (ESBL (+)) bacterial strains were detected in 49.3% (n = 70), with third-generation cephalosporin resistance in all and increased duration of hospitalization. The prevalence of UTI with ESBL (+) bacterial strains with multi-drug resistance is increasing in the hospitalized pediatric population, therefore rational use of antibiotics is essential. © 2015 Japan Pediatric Society.

Agriculture and food animals as a source of antimicrobial-resistant bacteria

PubMed Central

Economou, Vangelis; Gousia, Panagiota

2015-01-01

One of the major breakthroughs in the history of medicine is undoubtedly the discovery of antibiotics. Their use in animal husbandry and veterinary medicine has resulted in healthier and more productive farm animals, ensuring the welfare and health of both animals and humans. Unfortunately, from the first use of penicillin, the resistance countdown started to tick. Nowadays, the infections caused by antibiotic-resistant bacteria are increasing, and resistance to antibiotics is probably the major public health problem. Antibiotic use in farm animals has been criticized for contributing to the emergence of resistance. The use and misuse of antibiotics in farm animal settings as growth promoters or as nonspecific means of infection prevention and treatment has boosted antibiotic consumption and resistance among bacteria in the animal habitat. This reservoir of resistance can be transmitted directly or indirectly to humans through food consumption and direct or indirect contact. Resistant bacteria can cause serious health effects directly or via the transmission of the antibiotic resistance traits to pathogens, causing illnesses that are difficult to treat and that therefore have higher morbidity and mortality rates. In addition, the selection and proliferation of antibiotic-resistant strains can be disseminated to the environment via animal waste, enhancing the resistance reservoir that exists in the environmental microbiome. In this review, an effort is made to highlight the various factors that contribute to the emergence of antibiotic resistance in farm animals and to provide some insights into possible solutions to this major health issue. PMID:25878509

Antibiotic-prescribing patterns for Iraqi patients during Ramadan

PubMed Central

Mikhael, Ehab Mudher; Jasim, Ali Lateef

2014-01-01

Background During Ramadan, Muslims fast throughout daylight hours. There is a direct link between fasting and increasing incidence of infections. Antibiotic usage for treatment of infections should be based on accurate diagnosis, with the correct dose and dosing regimen for the shortest period to avoid bacterial resistance. This study aimed to evaluate the practices of physicians in prescribing suitable antibiotics for fasting patients and the compliance of the patients in using such antibiotics at regular intervals. Materials and methods An observational study was carried out during the middle 10 days of Ramadan 2014 in two pharmacies at Baghdad. A total of 34 prescriptions (Rx) for adults who suffered from infections were examined. For each included Rx, the researchers documented the age and sex of the patient, the diagnosis of the case, and the name of the given antibiotic(s) with dose and frequency of usage. A direct interview with the patient was also done, at which each patient was asked about fasting and if he/she would like to continue fasting during the remaining period of Ramadan. The patient was also asked if the physician asked him/her about fasting before writing the Rx. Results More than two-thirds of participating patients were fasting during Ramadan. Antibiotics were prescribed at a higher percentage by dentists and surgeons, for which a single antibiotic with a twice-daily regimen was the most commonly prescribed by physicians for patients during the Ramadan month. Conclusion Physicians fail to take patient fasting status into consideration when prescribing antibiotics for their fasting patients. Antibiotics with a twice-daily regimen are not suitable and best to be avoided for fasting patients in Iraq during Ramadan – especially if it occurs during summer months – to avoid treatment failure and provoking bacterial resistance. PMID:25473271

Antimicrobial Chemicals Are Associated with Elevated Antibiotic Resistance Genes in the Indoor Dust Microbiome.

PubMed

Hartmann, Erica M; Hickey, Roxana; Hsu, Tiffany; Betancourt Román, Clarisse M; Chen, Jing; Schwager, Randall; Kline, Jeff; Brown, G Z; Halden, Rolf U; Huttenhower, Curtis; Green, Jessica L

2016-09-20

Antibiotic resistance is increasingly widespread, largely due to human influence. Here, we explore the relationship between antibiotic resistance genes and the antimicrobial chemicals triclosan, triclocarban, and methyl-, ethyl-, propyl-, and butylparaben in the dust microbiome. Dust samples from a mixed-use athletic and educational facility were subjected to microbial and chemical analyses using a combination of 16S rRNA amplicon sequencing, shotgun metagenome sequencing, and liquid chromatography tandem mass spectrometry. The dust resistome was characterized by identifying antibiotic resistance genes annotated in the Comprehensive Antibiotic Resistance Database (CARD) from the metagenomes of each sample using the Short, Better Representative Extract Data set (ShortBRED). The three most highly abundant antibiotic resistance genes were tet(W), blaSRT-1, and erm(B). The complete dust resistome was then compared against the measured concentrations of antimicrobial chemicals, which for triclosan ranged from 0.5 to 1970 ng/g dust. We observed six significant positive associations between the concentration of an antimicrobial chemical and the relative abundance of an antibiotic resistance gene, including one between the ubiquitous antimicrobial triclosan and erm(X), a 23S rRNA methyltransferase implicated in resistance to several antibiotics. This study is the first to look for an association between antibiotic resistance genes and antimicrobial chemicals in dust.

Prevalence of veterinary antibiotics and antibiotic-resistant Escherichia coli in the surface water of a livestock production region in northern China.

PubMed

Zhang, Xuelian; Li, Yanxia; Liu, Bei; Wang, Jing; Feng, Chenghong; Gao, Min; Wang, Lina

2014-01-01

This study investigated the occurrence of 12 veterinary antibiotics (VAs) and the susceptibility of Escherichia coli (E. coli) in a rural water system that was affected by livestock production in northern China. Each of the surveyed sites was determined with at least eight antibiotics with maximum concentration of up to 450 ng L(-1). The use of VAs in livestock farming probably was a primary source of antibiotics in the rivers. Increasing total antibiotics were measured from up- to mid- and downstream in the two tributaries. Eighty-eight percent of the 218 E. coli isolates that were derived from the study area exhibited, in total, 48 resistance profiles against the eight examined drugs. Significant correlations were found among the resistance rates of sulfamethoxazole-trimethoprim, chloromycetin and ampicillin as well as between tetracycline and chlortetracycline, suggesting a possible cross-selection for resistance among these drugs. The E. coli resistance frequency also increased from up- to midstream in the three rivers. E. coli isolates from different water systems showed varying drug numbers of resistance. No clear relationship was observed in the antibiotic resistance frequency with corresponding antibiotic concentration, indicating that the antibiotic resistance for E. coli in the aquatic environment might be affected by factors besides antibiotics. High numbers of resistant E. coli were also isolated from the conserved reservoir. These results suggest that rural surface water may become a large pool of VAs and resistant bacteria. This study contributes to current information on VAs and resistant bacteria contamination in aquatic environments particularly in areas under intensive agriculture. Moreover, this study indicates an urgent need to monitor the use of VAs in animal production, and to control the release of animal-originated antibiotics into the environment.