Lactamase Production Research Articles

Antimicrobial Resistance: The 'Other' Pandemic! : Based on 9th Dr. I. C. Verma Excellence Award for Young Pediatricians Delivered as Oration on 19th Sept. 2021.

Antimicrobial resistance is projected to kill 10 million people by 2050. The biggest driver of antimicrobial resistance is excessive/unrestricted use of antimicrobials in humans and animals. Antimicrobial resistance is a problem in all types of pathogens including bacteria, mycobacteria, viruses, fungi, and parasites both globally and India and in both adults and children. The areas of greatest concern for India is the epidemic of MDR and XDR tuberculosis and resistance in gram-negative pathogens. The alarming rate of extended spectrum beta lactamase (ESBL) production in Enterobacteriales in both community and health care–associated infections is driving carbapenem use. Rates of carbapenem resistance are now significantly high in health care–associated gram negative pathogens with associated high mortality rates. The key solution to this antimicrobial resistance crisis needs participation of all stakeholders and lies in promoting rational antimicrobial therapy.

Prevalence and Phenotypic Profile of Antimicrobial Resistance Pattern of Multidrug Resistant Uropathogens in a Rural Tertiary Care Hospital, Gujarat, India

Introduction: Multidrug Resistant (MDR) organisms have become a major problem for the treatment of various infections and are imposing the greatest challenge to public health worldwide. Uncomplicated Urinary Tract Infections (UTIs) are treated empirically sometimes with broad spectrum antibiotics without performing drug susceptibility tests that adds to drug resistance in bacteria. Aim: To identify the current prevalence and evaluate phenotypic profile of antimicrobial resistance pattern of MDR uropathogens. Materials and Methods: This was a cross-sectional descriptive study conducted from January 2019 to July 2021 at Parul Sevashram Hospital Vadodara, Gujarat, India. Total 960 uropathogens were analysed for prevalence, their phenotypic antimicrobial resistance mechanism and antibiotic sensitivity pattern. Isolated organisms, their phenotypic resistance pattern and antibiotic sensitivity data was entered in Microsoft excel and data were analysed using Statistical Package for the Social Sciences (SPSS) 25.0 version. Results: During the study period, total 960 urinary isolates were analysed of which 891 (92.8%) were gram negative bacilli, 69 (7.2%) were gram positive cocci. Probable antimicrobial resistance pattern in gram negative isolates causing UTI were 317 (35.6%) of Extended Spectrum Beta Lactamase (ESBL) producer, While carbapenemase (+ or - ESBL) were 328 (36.8%) and impermeability carba (+ESBL or +High-Level Ampicillinase C (HL AmpC)) were 311 (34.9%). Amikacin was highly sensitive antibiotic in 378 (75.3%) of Escherichia coli (E. coli) and 111 (52.9%) of Klebsiella pneumoniae (K. pneumoniae) isolates causing UTI. Conclusion: The study concluded that carbapenem resistance was more in K. pneumoniae isolates causing UTI than E. coli. Aminoglycosides like amikacin was highly effective for the treatment of UTI caused by E.coli and K. pneumoniae.

Microbiological Study of Food Packaging Paper of Kathmandu Valley

Objectives: The purpose of this study was to isolate and identify microorganisms of food packaging papers of Kathmandu valley and determine antibiotic susceptibility of the isolates. Methods: A total of 34 food packaging paper samples were collected aseptically from hotels, bakeries and sweet shops (considered as closed shop) and open street vendors and were transported to microbiology laboratory of Golden Gate International College for processing. The isolates were identified by standard microbiological procedures and subjected to antimicrobial susceptibility testing by modified Kirby-Bauer disk diffusion method following CLSI guidelines. The rate of Extended Spectrum Beta- lactamase (ESBL) producing and multiple drug resistant (MDR) isolates were also determined. Results: All 34 samples yielded microbial growth with average microbial count of 4.145×105 CFU/g. Among 103 microbial isolates, 78 were bacteria, 15 molds and 10 yeasts. The predominant bacterial and mold isolates were Bacillus spp (43.59%) and Cladosporium spp (46.67%) respectively. Ciprofloxacin (42/43) and Amikacin (42/43) were the most effective and ampicillin (39/43) was most resistant antibiotics for Gram negative bacteria. A total of 9.30% Gram negative isolates were identified as ESBL producing and MDR strains. Conclusion: This result indicates that potential pathogens are found in food packaging papers which can be threat to health of consumers as they may act as a source of food borne infection.

1438. Prevalence and Risk Factors for Extended Spectrum Betalactamases Among Hospitalized Patients with Community Acquired Pyelonephritis in Colombia

BackgroundUrinary tract infections (UTI) are the most frequent bacterial infection in hospitalized patients. Extented spectrum betalactamases (ESBL) producing bacteria causing UTI have become more prevalent. Escherichia coli (E. coli) is the most frequent ESBL producing bacteria isolated in UTI. This drug resistant organisms are associated with poorer outcomes for patients. In low income countries, approaching to and treating ESBL E. coli, represent a major challenge for health care centers. MethodsA retrospective cohort of adult patients with community acquired pyelonephritis caused by Escherichia coli was identified in a tertiary hospital in Colombia. Susceptibility was performed with Vitek (BioMerieux, France); extended spectrum beta lactamase (ESBL) production was defined phenotypically. Inclusion criteria were adult patients hospitalized with a positive urine culture for E. coli. Demographic and clinical characteristics were searched in electronic records. Risk factors associated with ESBL production were identified by using a multivariate logistic regression analysis.ResultsDuring 7 years 817 patients with pyelonephritis caused by E. coli were identified. 79 (9.7%) of them were caused by ESBL producers. Women were 66% and 408 (74.8% of them) had menopause. Mean age was 64.2 years (standard deviation of 19.1). Of the cohort, 481 (561.1%) had at least some comorbidity and was frequent to find diabetes (18.5%), immunosuppression due to oncologic disease or medications (18.4%), urolithiasis or previous surgical procedures (17%). After logistic regression, risk factors identified to predict ESBL production, were: being a man (aOR 5.4, 2.1-18.2), a woman with menopause (aOR 2.9, 1.3 -9.9), and the Charlson score (aOR 0.83, 0.73 – 0.96). Previous antibiotic use was not related to ESBL infection. ConclusionIn this relatively large cohort of patients with pyelonephritis caused by E. coli, ESBL production risk factors were not clearly identified other than sex and menopause. Curiously, Charlson score predicted a lower risk of resistance. Other factors (food consumptions and others) might be driving the resistance in the community in E. coli. Disclosures Jorge Cortes, MD, Pfizer (Research Grant or Support)

PATHOGENS ASSOCIATED WITH BACTERIAL BLOODSTREAM INFECTIONS AT THE FACILITY 2 OF NATIONAL HOSPITAL FOR TROPICAL DISEASES IN DONG ANH DISTRICT (2018 - 2020)

Objectives: 1. Identifying the pathogens associated with bacterial BSIs at the ability 2 of NHTD in Dong Anh district from 2018 to 2020. 2. Identifying antimicrobial susceptibility of bacteria isolated from blood samples.Subjects and methods: A descriptive study was conducted at the National Hospital for Tropical Diseases between January 2018 and December 2020. Cases of BSI were determined from records in the microbiology department with positive two blood cultures in the first episode.Results: A total of 330 patients with BSI were included for microbiological analysis. The predominant pathogens were: K. pneumoniae (15.1%), E. coli (14.2%), S. aureus (14.2%),Acinetobacter baumannii (6.8%) and Stenotrophomonas maltophilia (5.3%). There were two species with a high proportion of extended - spectrum beta - lactamase (ESBL) production among Enterobacteriaceae were E. coli (68.8%) and K. pneumonia (15.7%). All of S. aureus isolated strainswere susceptible to vancomycin and linezolid.Conclusions: Enterobacteriaceae (predominantly K. pneumoniae and E. coli) is the most common cause of bloodstream infections in a tertiary referral clinic in NHTD (a branch at Dong Anh district) in 2018 - 2020.

Device-related infections in a pediatric intensive care unit: The Jordan University of Science and Technology experience.

To estimate the prevalence of the most frequent infections related to device utilization and their antimicrobial sensitivity panel, and to investigate the overall incidence of device associated infection rates per 1000 device days, at the pediatric intensive care unit of the Jordan University of Science and Technology.This is a retrospective study from a single pediatric intensive care unit. Data were collected in relation to bloodstream infections associated with central venous catheters, pneumonia associated with ventilator endotracheal tubes, and urinary tract infections associated with Foley catheters, between January 2013 and December 2018, according to the center of disease control and prevention protocols.During the 5-year study, 3195 patients were admitted to the pediatric intensive care unit for a total of 16,487 days. Forty-six patients (1.4%) developed 55 infections, with a median incidence rate of 7.4, 3.7, and 0.7 per 1000 days for central line associated infections, ventilator associated pneumonia, and catheter associated infections, respectively. The commonest isolated microorganisms were gram-negative bacteria in 89.1% of cases, and fungi in 10.9% of cases. Among the resistant bacterial isolates, 59.2% were multidrug resistant, and 32.6% were extended spectrum beta lactamase producers Klebsiella pneumoniae and Eschericia coli. High infection rates were related to Acinetobacter baumannii and K pneumoniae, associated with high resistance to cephalosporins. Susceptibility was highest to tigecycline and imipenem at 42.9% and 32.7% respectively.Microbial isolates are commonly associated with healthcare device insertions in pediatric intensive care unit, invasive bacterial infections associated with critical morbidity and mortality. Further studies on device associated infections are recommended for regional profiling purposes.

Piperacillin/tazobactum and cefotaxime decrease the effect of beta lactamase production in multi-drug resistant K. pneumoniae

BackgroundWorldwide, multi-drug resistant Klebsiella pneumoniae (K. pneumonia) and their virulence’s were contributed more in the multi-drug resistant effect. According to the World Health organization report, it is an emerging thread in developing countries and also comes under first ever critical list. In this context, the current study was concentrated on detection of extended spectrum beta lactamase (ESBL) producing strain and their antimicrobial susceptibility study of K. pneumoniae. Materials and methodsFirstly, the multi-drug resistant effect of the K. pneumoniae was identified from specific CLSI guidelines recommended antibiotics by disc diffusion method. Consecutively, the primary ESBL identification test was performed using ceftazidime and cefotaxime, followed by double disc combination and phenotypic confirmation tests using ceftazidime/clavulanic acid and cefotaxime/clavulanic acid. Finally, the minimum inhibition concentration of some important sensitive antibiotics were performed against selected K. pneumoniae was confirmed by micro broth dilution method. Results and conclusionsThe current result was most favorable to selected K. pneumoniae with more multi drug resistant characteristic nature. All the performed antibiotics were almost more sensitive to selected K. pneumoniae. The effective antibiotics of piperacillin was also exhibited more resistant effect against tested bacteria and it cleaved the bacterial enzyme clearly. The present result of primary ESBL identification test result was exhibited with ≤22 mm and ≤27 mm against ceftazidime and cefotaxime were observed respectively. Followed result of double disc combination and phenotypic confirmation experiments results were clearly stated that the selected K. pneumoniae was ESBL producer. The ceftazidime, cefotaxime and ceftazidime/clavulanic acid and cefotaxime/clavulanic acid were exhibited with merged zones and ≥5 mm zones around the combination disc when compared with disc alone were observed. All the ESBL detection test results were clearly indicated that the selected K. pneumoniae strain was ESBL producer.

Distribution of blaTEM Gene among Escherichia Coli Strains Isolated from Different Clinical Samples in Erbil City

Background: Emerging antibiotic resistance and Extended-Spectrum Beta-Lactamase (ESBL) producing Escherichia coli causing different nosocomial infections are rapidly increasing at alarming levels and it poses a major health burden in the 21st century globally. Objective: The aim of this study is to determine the distribution of blaTEM gene ESBLproducing E. coli from clinical specimens in different hospitals in Erbil city. Methods: A total of 200 samples were collected from (sputum, urine, wound) from patients attended public hospitals in Erbil city. The isolation and identification of Escherichia coliand antimicrobial susceptibilitywere performed by using Vitek 2 compact -lactamase production in E.coli was confirmed by using both Double disk diffusion and Standard disk diffusion techniques. Moreover, PCR technique was used for genotypic detection of an ESBL gene blaTEMaccording to the standard protocol. Results: Out of 200 samples 60(30%) of E. coli isolates and the highest rate of E. coli isolates were obtained from the urine samples (20%) and the lowest number was isolated from sputum specimens (2.5%). The ESBL-producing Escherichia coli isolates were detected using double disk synergy test (76.7%) in comparison to standard disk diffusion test (80%). Genotypic screening results confirmed that all ESBL-producing E. coli isolates (66.7%) were carried blaTEM gene (700 bp) in clinical specimens (50% urine, 13.33% wound and 3.33% sputum). All ESBL-positive E. coli isolates showed high rates of susceptibility to Carbapenems antibiotic group including Imipenem (83.3%), Meropenem (81.7%), and Ertapenem (80.0%). Conclusions: -lactamase gene in ESBL-producing E. coli observed in this study for the first time is considered as alarming because there is a limited treatment options remained for infections. Attempts to reduce the dissemination of multi-drug resistant E. coli through compliance with strict hospital infection control and prevention standards are imperative. Findings of this study may help clinicians selecting appropriate antimicrobial therapy in patients with different infections caused by ESBLproducing E. coli.

Detection of biofilm formation, extended spectrum beta lactamase production and their correlation with antibiotic resistance among uropathogenic Escherichia coli

Urinary tract infections (UTI) are most common bacterial infections encountered in clinical practice and is predominant organism causing UTI.: 1.To study antibiotic resistance pattern among uropathogenic (UPEC). 2.To study extended spectrum beta lactamase (ESBL) production and their correlation with antibiotic resistance among uropathogenic (UPEC). 3.To study biofilm formation and its correlation with antibiotic resistance among uropathogenic (UPEC)A prospective study was conducted on first 100 isolated from urine specimens of patients suspected to be having urinary tract infection between January 2016 and December 2016 received at Department of Microbiology, SIMS Shimoga. Fresh midstream urine samples were aseptically collected in sterile containers and plated on Blood agar & MacConkey agar plates using a standard loop technique & the growth was processed by standard bacteriological technique. Biofilm detection was done by tube and microtitre plate method. ESBL detection was done according to CLSI criteria. Antimicrobial sensitivity testing was done using Kirby-Bauer methods on Mueller-Hinton agar. Results were interpreted as per the CLSI guidelines.Antibiotic sensitivity of was nitrofurantoin (100%) fosfomycin (100%) imipenem (77%) cotrimoxazole (61%) amikacin (47%) aztreonam (53%) piperacillintazobactam (41%). cefotaxim (25%) ceftazidime (32%) norfloxacin (20%) ampicillin-sulbactam (12%) ciprofloxacin (15%), levofloxacin (12%), amoxiclavulanicacid (15%). ESBL positive were 83% (screening), 80% (confirmatory). Biofilm positive were 63% (tube method) 79% (Microtiterplate method).This study showed Fosfomycin and Nitrofurantoin were the most sensitive drug. Study shows antibiotic resistance was seen more in ESBL and Biofilm producers compared to non ESBL and non biofilm producers.

PBI-012 - Prevalence of Extended Spectrum Beta Lactamase (ESBL) producers among Escherichia coli from various clinical isolates

PBI-012 - Prevalence of Extended Spectrum Beta Lactamase (ESBL) producers among Escherichia coli from various clinical isolates

Metallo-β Lactamase Producing Non-Fermentative Gram-Negative Bacilli from Various Clinical Isolates in a Tertiary Care Hospital: A Descriptive Cross-sectional Study.

Non-fermentative gram-negative bacilli are common causes of human infections especially nosocomial infections. These organisms are usually resistant to multiple antimicrobial agents including carbapenems. The study aimed to find out the prevalence of metallo-β-lactamase producing non-fermentative gram-negative bacilli among the samples which yielded growth of bacteria in a tertiary care hospital. This is a descriptive cross-sectional study conducted in a tertiary care hospital from February 2017 to May 2017. Convenience sampling method was used. Bacterial identification, characterization and antimicrobial susceptibility testing were done by following standard microbiological guidelines. Metallo-β-lactamase production was detected by using combined disk diffusion test and double-disc synergy test. Data were analyzed by using Statistical Package of Social Science software version 16. Point estimate at 95% confidence interval was calculated along with frequency and proportion for binary data. Among 628 samples which yielded growth of bacteria, 118 (18.79%) at 95% Confidence Interval (15.74-21.84) were metallo-β-lactamase producing non-fermentative gram-negative bacilli. Among them, 54 (45.76%) were Pseudomonas aeruginosa and 64 (54.24%) were Acinetobacter baumannii. A high prevalence of metallo-β-lactamase production was observed among the nonfermentative gram-negative bacilli than the study done in similar settings. It is mandatory to perform routine monitoring of metallo-β-lactamase producing isolates in clinical laboratories in order to help the clinicians prescribe proper antibiotics.

EXTENDED SPECTRUM BETA LACTAMASE PRODUCING UROPATHOGENS IN A TERTIARY CARE HOSPITAL IN SOUTH INDIA: A CLINICO MICROBIOLOGICAL STUDY

Introduction: Urinary Tract Infection (UTI) is the most common bacterial infection encountered in both hospital and community setup and the presence of drug resistance carries remarkable clinical implication. Drug resistant phenotypes like ESBL (Extended Spectrum Beta lactamase producers) are difcult to treat causing increased morbidity. Aims: The present study aims to determine the prevalence of ESBL producing Enterobacteriacea among Uropathogens and to determine the Antibiotic susceptibility pattern. Materials and Methods :A total of 726 urine samples were obtained and processed as per standard microbiological techniques .Antibiotic susceptibility testing was done by Kirby Bauer disc diffusion method. All the isolates were screened for ESBL production and conrmed by Double Disc Synergy test (DDST).Differences between the antibiotic susceptibility pattern ,Various risk factors were assessed among the ESBL producing and non ESBLproducing bacteria and the signicance was analyzed . Statistical analysis used:Chi square test.(p < 0.05 signicant) Results: A total of 726 urine samples were processed of which 421 bacteria belonging to Enterobacteriaceae were included in the study. Most common organism isolated was Escherichia coli 279 (66.27%).Highest susceptibility was observed for Imipenem 361 (85.7%) and Amikacin 356 (84.5%).Out of 461 isolates, 235 (55.8%) isolates were positive for ESBL screening all the isolates were conrmed with DDST. There was a signicant difference for Diabetes mellitus, CAUTI and Inpatients among the antibiotic susceptibility pattern between ESBL and non ESBL producers.(p<0.0001) Conclusions: Early detection of Multidrug resistance isolates like ESBLproducers in routine testing could help avoid treatment failure. Screening for ESBL production needs to be carried out regularly in every clinical diagnostic laboratory to guide clinicians in proper selection of antibiotics. Continued monitoring of the susceptibility pattern of ESBLproducing bacteria will provide valuable information regarding the local antimicrobial susceptibility pattern which in turn will guide in choosing the initial empirical therapy

Prevalence of common bacterial etiology and antimicrobial susceptibility pattern in patients with otitis media in Duhok Province –Iraq

     Otitis media is the most frequent type of ear infection. It is a major health problem for both children and adults but the proportion is different in different countries. The current study was designed to determine the frequency of bacterial isolates causing otitis media and their antimicrobial resistance profile to assess the incidence of multidrug-resistant (MDR), extensively drug-resistant (XDR), and pan drug resistance (PDR) among the isolated pathogens. Also, to determine the various risk factors (age, gender, type, and site of infection) associated with ear infection. A total of 200 ear discharge samples were collected from patients aged 1-77 years attending the Ear, Nose, and Throat (ENT) unit in Azadi Teaching Hospital in Duhok city from November 2018 to September 2019. The clinical samples were cultured and bacterial isolates were identified by standard microbiological methods then confirmed by VITEK® 2 Compact automated system. All gram-negative bacterial isolates were studied phenotypically for Extended Spectrum Beta Lactamase production. Out of 200 ear swabs, 95% confirmed positive culture; 85.8% were bacterial isolates. From the total bacterial isolates, 57% were gram-positive bacteria, while gram-negative bacteria were 43%; with predominant of Pseudomonas aeruginosa, (22%) followed by Staphylococcus aureus (19%) and Coagulase negative Staphylococci (18%). The prevalence of otitis media was not significantly affected by gender. The majority of patients belonged to the age group (1-10) years old. 64.1% of the isolates were characterized as MDR, 31.7% were XDR, with one (0.7%) as PDR. Among these, 60.7% isolates were ESBL producers, Pseudomonas aeruginosa was the most frequent ESBL- producing isolates (45.9%), followed by Proteus spp (18.9%). The in-vitro sensitivity results indicated that Gentamycin and Ciprofloxacin were effective antibiotics in the treatment of otitis media. Additionally, Meropenem, Imipenem, Cefepime, and Azetronam were also the most effective drug against Pseudomonas aeruginosa. We concluded that the drug resistant isolates were common, worryingly high, leaving only limited drugs as a treatment choice.

Molecular Characterization of Extended Spectrum Beta – Lactamase Producing Escherichia Coli Isolated from Pregnant Women with Urinary Tract Infections Attending Ante–Natal Clinics in Ilorin Metropolis

Background: The emergence of multidrug- resistance Enterobacteriaceae especially in E. coli bacteria associated with Urinary Tract Infections (UTIs) in pregnancy is a serious menace globally posing health challenges and confounding successful empirical treatment as well as increasing pregnancy – related complications.Objectives: The aim of this study is to determine the phenotypic and genotypic characteristics of Extended Spectrum Beta – Lactamases (ESBLs) producing E. coli (ESBLs – EC) isolates in pregnant women attending ante – natal clinics within Ilorin - Kwara State, Nigeria.Materials and methods: A total of 53 non - repeated E. coli isolates from urine samples of pregnant women were presumptively identified using standard bacteriological method and confirmed by commercially available Microgen® Identification Kits. Phenotypic detection of ESBLs was determined using antibiotics susceptibility test and double disc synergy Method for screening and confirmation respectively. Polymerase Chain Reaction (PCR) was further used for the genotypic detection of ESBLs genes.Results: A total 88.67% (47/53) of E. coli exhibited resistance to the cephalosporins of which aztreonam was the highest (75.47%) and the least was cefpodoxime (35.84%) while 85.10% were confirmed positive for ESBL production. The genotypic detection showed the most occurring genotype was blaTEM (50%) blaOXA (27.7%), blaGES (22.5%), blaSHV (15%), blaCTXM and blaVEB (7.5%) while sixty – four (64%) of isolates co – harbored two or more gene. BlaTEM and blaOXA were dominant.Conclusion: This study showed high resistance of E. coli to the third generation cephalosporins harboring different ESBL genes which increases UTIs complexity and limit therapeutic options in pregnancy. Therefore, continuous monitoring of resistance in E. coli, effective appraisal of antibiotic control policies and rational use of antibiotics is therefore encouraged.

Occurrence of Extended Spectrum Beta Lactamase (ESBL) Producers, Quinolone and Carbapenem Resistant Enterobacteriaceae Isolated from Environmental Samples along Msimbazi River Basin Ecosystem in Tanzania.

We conducted environmental surveillance of antimicrobial resistance (AMR) bacteria in the Msimbazi river basin in Tanzania to determine the occurrence of extended-spectrum β-lactamase (ESBL)-producing, carbapenem resistant Enterobacteriaceae (CRE) and quinolone resistant Escherichia coli and Klebsiella spp. A total of 213 Enterobacteriaceae isolates were recovered from 219 samples. Out of the recovered isolates, 45.5% (n = 97) were Klebsiella pneumoniae and 29.6% (n = 63) were Escherichia coli. K. pneumoniae isolates were more resistant in effluent (27.9%) compared to the E. coli (26.6%). The E. coli had a higher resistance in river water, sediment and crop soil than the K. pneumoniae (35 versus 25%), respectively. Higher resistance in K. pneumoniae was found in nalidixic acid (54.6%) and ciprofloxacin (33.3%) while the E. coli isolates were highly resistant to ciprofloxacin (39.7%) and trimethoprim/sulfamethoxazole (38%). Resistance increased from 28.3% in Kisarawe, where the river originates, to 59.9% in Jangwani (the middle section) and 66.7% in Upanga West, where the river enters the Indian Ocean. Out of 160 E. coli and K. pneumoniae isolates, 53.2% (n = 85) were resistant to more than three classes of the antibiotic tested, occurrence being higher among ESBL producers, quinolone resistant and carbapenem resistant strains. There is an urgent need to curb environmental contamination with antimicrobial agents in the Msimbazi Basin.

Antibiotic Sensitivity Pattern and Plasmid Profile of Bacteria Isolated from Diabetic Ulcers in Mbano Metropolis, Imo State, Southeastern Nigeria

The study was undertaken to evaluate the bacteriology and antibiogram of isolates from diabetic patients with chronic foot ulcers in Nigeria. A total of 150 pus samples were collected and processed according to standard aerobic and anaerobic microbiological methods. Antibiogram was done using Kirby-Bauer method. Biofilm tests, ESBL & AmpC production was conducted using Congo red agar, Double disc synergy test and Cefoxitin disc test respectively. Total number of isolates obtained was 210. The Plasmid profiles of some of the Multi-Drug Resistance (MDR) isolates were carried out using the alkaline lysis method for plasmid extraction and electrophoresis on agarose gel with standard markers. The most frequently isolated aerobic organism in the study was Escherichia coli (32.1%) while the least occurring was Enterobacter spp (1.57%). For the anaerobes, Peptostreptococcus spp (40%) was the highest isolated bacterium.Percentage of Extended Spectrum -lactamase ( ESBL) producers among E. coli isolates was 44%. Percentages of biofilm formation potential among the isolates were: E. coli (36.8%), S. aureus (23.1%) and Proteus vulgaris (4.2%). Escherichia coli and S. aureus showed considerable levels of resistance to some common antibiotics. No methicilin resistant S. aureus was encountered. AmpC producers encountered were Klebsiella pneumonia (10%) and E. coli (8.1%). Post-curring antibiogram tests revealed that nine isolates carried plasmids, suggesting that the mode of resistance may be plasmid mediated.

English

Carbapenems are group of extended-spectrum β-lactam antimicrobials frequently used for treating multidrug-resistant Gram-negative bacilli (GNB) infections. This study aimed at detecting and characterizing carbapenem resistance (CR) genes among GNB isolated from patients treated in neonatal intensive care unit (NICU) of Mansoura University Children's Hospital (MUCH), Egypt. It is a prospective study conducted from 2015 to 2016. A total of 158 GNB isolates were examined for CR both phenotypically and genotypically. Among 158 Gram negative isolates, there were 58 (36.7%) CR strains. Extended-spectrum β-lactamase (ESBL) production was confirmed in all 58 (100%) isolates. Carbapenemase production was detected in 52 (89.5%) strains while metallo beta-lactamase (MBL) production was found in 33 (56.9%) strains.  Molecular characterization of CR strains revealed that 57 (98.3%) isolates were positive for carbapenemase encoding genes. KPC gene was the most frequent detected gene (34/58).  VIM, IPM, OXA and NDM genes were also detected in 15, 13, 9 and 1 isolate, respectively. Only one isolate was negative for all encoding resistance genes despite positive for ESBL phenotype. Infection with CR strains has been increasing in clinical settings which limit the use of carbapenems.   Key words: Gram-negative bacilli, carbapenem resistance, carbapenemase, metallo beta-lactamase, multiplex polymerase chain reaction (PCR), carbapenemase encoding genes, neonatal intensive care unit.

Detection of extended spectrum beta-lactamase genes in strains of Escherichia coli and Klebsiella pneumoniae isolated from recreational water and tertiary hospital waste water in Zaria, Nigeria

ABSTRACT Extended spectrum beta-lactamase (ESBL) producing bacteria pose a severe health risk globally. This study focused on detecting ESBL genes in Escherichia coli and Klebsiella pneumoniae isolated from a recreational water source and the waste water from a tertiary hospital in Zaria, Kaduna State, Nigeria. The isolates (twenty-two) were screened phenotypically for extended spectrum beta lactamase production using the double disk synergy test. Of the isolates, 13 (59.1%) were E. coli, while 9 (40.9%) were Klebsiella pneumoniae; 17 (77.3%) were isolated from the waste water and 5 (22.7%) were isolated from the recreational water. Six (27.2%) of them showed ESBL production phenotypically; however, PCR amplification of the ESBL genes showed that only five of them had at least one of the genes. The presence of ESBL bacteria in hospital waste water and surface waters highlights that water matrices are important routes of transmission of antibiotic resistant bacteria.

First Detection of Human ST131-CTX-M-15-O25-B2 Clone and High-Risk Clonal Lineages of ESBL/pAmpC-Producing E. coli Isolates from Diarrheic Poultry in Tunisia.

Circulation of a multi-resistance clone of bacteria associated with genetic elements in diseased animals constitutes a global public health problem. Our study focused on the characterization of the support of ESBL in cefotaxime resistant E. coli (CTXR) isolates recovered from poultry with diarrhea, analysis of their clonal lineage, and virulence-associated genes. The study was carried out on 130 samples of chickens with diarrhea, collected in 2015 from poultry farms in Tunisia. Isolates of 20 CTXR E. coli strains were identified as ESBL and AmpC β- lactamase producers. The following β-lactamase genes (number of isolates) were detected: blaCTX-M-15+ blaOXA1 (4), blaCTX-M-15 + blaOXA1 + blaTEM-1b (2), blaCTX-M-1 + blaTEM-1b (9), blaCTX-M-1 (2), blaCMY2 + blaTEM-1b (3). Six E. coli harboring blaCTXM-15 were allocated to ST131-B2-O25b-; six and three blaCTX-M-1 were grouped in ST155, ST10, and ST58, respectively, related to the phylogroup D and A. The qnrB gene, the variant aac(6′)-Ib-cr, and the class 1 integrons with different gene cassettes, were detected amongst our 20 isolated strains, which were classified as ExPEC and aEPEC. Our findings highlighted the emergence of the human pandemic ST131-CTX-M-15-O25-B2 clone and the high risk of such clonal lineage strains in diarrheic poultry, in Tunisia, which could constitute a risk of their transfer to healthy animals and humans.

P682 Antibiotic resistome profiles of fecal Escherichia coli isolates in association with Crohn’s disease

Abstract Background In recent years, there was a growing interest in the modulation and manipulation of the intestinal flora to treat patients through fecal microbiota transplantation (FMT). Unfortunately, 2 cases of bacteremia via FMT in 2019 occurred in patients due to extended-spectrum beta–lactamase–producing E. coli from the same stool donor. However, one of the recipients did not get an active infection. So, the association between health status and bacterial ability to resist chemicals requires further investigations. Methods Totally, 63 E. coli strains from 32 fecal samples (14 CD patients and 18 controls) were whole-genome sequenced on the Miseq platform (project #0671-2020-0058). The strains were tested against 15 antibiotics by a disc-diffusion assay according to EUCAST guidelines. E. coli ATCC 25922 was used as a control. Antibiotic resistance genes were predicted by the Resistance Gene Identifier and CARD database. Results All strains tested were susceptible only to meropenem (Figure 1). The proportion of multidrug-resistant strains in CD patients and controls did not differ significantly. Strains from both groups differed in sensitivity to amikacin and levofloxacin (Fisher’s exact test, p<0.1). Ciprofloxacin, widely used in therapy, was less effective against CD-derived strains (15%) compared to controls (3%). The inefficiency of fluoroquinolones could be due to plasmid-associated genes (qnrS1, qnrB19) and mutations in chromosome genes (gyrA, parC). Several strains carried aminoglycoside transferase genes, but only 1 CD-derived strain was non-sensitive. Susceptibility to tetracyclines did not differ between groups, and almost all strains, growing on the antibiotic, contained efflux pump genes (tetA, tetB, tetD, tetR). About half of the strains from both groups were active against penicillins carrying genes for class A (TEM-1, TEM-150) and D beta-lactamases (OXA-1). TEM-150 was only in control strains. Cephalosporin-resistant strains were in both groups and harbored AmpC type β-lactamases. Almost all strains had multidrug efflux systems (MdtEF-TolC, EmrAB-TolC, EmrKY-TolC, AcrAB-TolC), MdtG and AcrD efflux pumps, and their regulators. Although all strains contained pmrF and pmrC genes, only 1 CD-derived strain was non-sensitive to polymyxin. Figure 1. Antibiotic resistance of E. coli strains (in %, * - p < 0.1) Conclusion Thus, the differences in susceptibility between CD- and control-derived strains were revealed. However, E. coli strains from healthy subjects contained antibiotic resistance genes and demonstrated activity against antibiotics of various categories, which might be crucial and should be taken into account for a safe and effective therapy in the treatment of CD.