Extended-spectrum Beta-lactamase Screening Research Articles

Extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in local and imported poultry meat in Ghana

Antibiotic use in animal husbandry has raised concerns on the spread of resistant bacteria. Currently animal products are traded globally with unprecedented ease, which has been challenging the control of antimicrobial resistance. This study aims to detect and characterize extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae from imported and locally produced poultry products sold in Ghana.Local and imported chicken meat was collected from 94 stores and markets throughout Kumasi (Ghana) and cultured on selective ESBL screening agar. Phenotypic ESBL-producing E. coli and K. pneumoniae isolates were confirmed by combined disc test and further characterized by antibiotic susceptibility testing, amplification of the blaCTX-M, blaTEM and blaSHV genes as well as multilocus sequence typing (MLST) and linked to the country of origin.Out of 200 meat samples, 71 (36%) samples revealed 81 ESBL-producing isolates (46 E. coli and 35 K. pneumoniae), with 44% (30/68) of local poultry and 31% (41/132) of imported products being contaminated. Most ESBL-producing isolates harboured the blaCTX-M-15 gene (61/81, 75%) and the dominant Sequence Types (ST) were ST2570 (7/35, 20%) among K. pneumoniae and ST10 (5/46, 11%) among E. coli.High numbers of ESBL-producing bacteria, particularly on local but also imported poultry meat, represent a potential source for human colonization and infection as well as spread within the community. Surveillance along the poultry production-food-consumer chain would be a valuable tool to identify sources of emerging multidrug resistant pathogens in Ghana.

Incidence of multidrug resistance and extended-spectrum beta-lactamase expression in community-acquired urinary tract infection among different age groups of patients.

OBJECTIVES:Urinary tract infection (UTI) is a frequent disorder and depends on age and gender. Ineffective empiric treatment of UTI is common when associated with extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae. The aim of the study was to investigate the prevalence of Gram-negative uropathogens of E. coli and K. pneumoniae in different age groups along with the identification of ESBL-producing uropathogens and antimicrobial susceptibility profiles.MATERIALS AND METHODS:A total of 247 uropathogens of E. coli and K. pneumoniae were collected over a period of 1 year (January–December 2015) from various diagnostic centers of Karachi city (Pakistan). Antimicrobial susceptibility analysis was performed by disc diffusion method, and identification of ESBL was performed by double disc synergy test. Categorical data of ESBL and non-ESBL uropathogens were analyzed by Pearson's Chi-square test.RESULTS:The study of 247 patients with community-acquired UTI comprised 72% females and 28% males, illustrating an increased prevalence of UTIs among females. It was also revealed that 90% belonged to the age group of 16–30 years whereas 78% related to the age group of 46–60 years. ESBL was found positive in 33.5% (63/188) of E. coli and 15.25% (9/59) in K. pneumonia, with a significant association i.e., (p =0.007). Amikacin, fosfomycin, imipenem, and tazobactam/piperacillin were found to be the effective treatment options. A significant association was found between ESBL-producing uropathogens against ciprofloxacin, enoxacin, and amoxicillin/clavulanic acid resistance (P < 0.05).CONCLUSIONS:It was concluded that for effective treatment of UTIs, appropriate screening of ESBL and culture sensitivity must be employed instead of empiric treatment.

Fecal carriage of extended-spectrum beta-lactamase and ampc beta-lactamase-producing enterobacteriaceae in a turkish community.

Community-acquired infection caused by extended-spectrum beta-lactamase (ESBL)-producing microorganisms has an increasing frequency. The aim of this study was to determine the fecal carriage of ESBL and AmpC beta-lactamase-producing Enterobacteriaceae in community and to investigate cefotaxime-M (CTX-M) genes among ESBL isolates. A total of 1402 fecal specimens which were collected from outpatients included in the study. ESBL screening, ESBL production, and AmpC beta-lactamase detection were performed. Matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) was used for identification of species. Antibiotic susceptibilities of the isolates were detected by disk diffusion method. CTX-M beta-lactamase genes were investigated by polymerase chain reaction. During the study period, a total of 1402 fecal samples were analysed with ESBL screening test and 490 Enterobacteriaceae strains isolated from these samples (Escherichia coli [n = 461, 94.1%], Klebsiella pneumoniae [n = 25, 5.1%], and Enterobacter cloacae [n = 4, 0.8%]). Fecal carriage of ESBL-producing Enterobacteriaceae in the community was 34.3%. AmpC beta-lactamases were detected in 26 (5.3%), and the frequency of CTX-M was found as 96.9%. The resistance rates of the E. coli strains to fluoroquinolones, trimethoprim-sulfamethoxazole, and carbapenems were 31.2%, 33.3%, and 0%, respectively. The relative high prevalence of fecal carriage of ESBL-producing bacteria in community warrants further study in this field including developing policies about antimicrobial use and close monitoring of resistance patterns.

Prevalence of Extended Spectrum Beta-Lactamase Producing Escherichia coli and Klebsiella species from Urinary Specimens of Children attending Friendship International Children’s Hospital

Extended-spectrum β-lactamase producing E. coli and K. pneumoniae is a serious threat to the patients. These organisms are major extended spectrum beta lactamase (ESBL) producers. The objective of this study was to determine the prevalence of Extended spectrum β- lactamase producing strains of Escherichia coli and Klebsiella spp isolates from the urine sample of children visiting International Friendship Children Hospital. During the seven months, between June 2016 to December 2016, 1018 mid-stream urine samples(MSU) were collected from patients suspected of having UTI. The samples were investigated by conventional semi-quantitative culture technique and identification of E. coli and Klebsiella spp. was done by microscopy and biochemical test. Antibiotic susceptibility test of isolates was performed by modified Kirby Bauer Disc diffusion test. ESBL screening test was done by using 3rd generation Cephalosporin and confirmation done by combination disc diffusion method. Out of total 1018 MSU samples investigated, 200(19.64%) isolates of E. coli and 28(2.7%) isolates of Klebsiella spp. making a total of 228(22.39%) were found to cause significant bacteriuria. 76(33.33%) isolates, from those causing significant bacteriuria, were Multi-drug resistant organisms. Out of 228 isolates, 54(23.68%) were ESBL producers, that includes 51(25.5%) Escherichia coli and 3(12.5%) Klebsiella pneumoniae. ESBL producers were more common in in-patient (36.17%) than out-patient (20.44%). Most of the ESBL producers were resistance to amoxicillin, followed by Cotrimoxazole and Ciprofloxacin respectively. They were highly sensitive to Imipenem, Tigecycline, Amikacin, Piperacillin-Tazobactam, and Nitrofurantoin. High prevalence of ESBL producing E. coli and Klebsiella pneumoniae was found among children. Regular and routine monitoring of ESBL producing isolates is essential.Nepal Journal of Biotechnology. Dec. 2017 Vol. 5, No. 1: 32-38

CTX-M-15-Type Extended-Spectrum Beta-Lactamase-Producing Escherichia coli as Causative Agent of Bovine Mastitis.

In the present study, 3 quarter milk samples from 3 cows showing clinical signs of mastitis were investigated. Three Escherichia coli were isolated and were found resistant to ceftiofur and cefquinome. The isolates were detected as extended-spectrum beta-lactamase (ESBL) producers by the Clinical and Laboratory Standards Institute (CLSI) ESBL screening test and combined disc method. CTX-M- and TEM-type beta-lactamase genes (blaCTX-M blaTEM) were detected by polymerase chain reaction in the isolates. Sequencing of blaCTX-M and blaTEM genes showed that the isolates were both TEM-1- and CTX-M-15-type beta-lactamase producers. The isolates were tested by agar disc diffusion test for susceptibility to various classes of antibiotics (aminoglycosides, quinolones, phenicols, folate pathway inhibitors, and tetracyclines), and they were determined as multidrug resistant. Therefore, this is the first report indicating the involvement of multidrug-resistant CTX-M-15-type ESBL-producing E. coli as a cause of bovine mastitis in Turkey.

Meta-analysis of proportion estimates of Extended-Spectrum-Beta-Lactamase-producing Enterobacteriaceae in East Africa hospitals.

BackgroundA high proportion of Extended-Spectrum-Beta-Lactamase (ESBL) producing Enterobacteriaceae is causing common infections in all regions of the world. The burden of antibiotic resistance due to ESBL in East Africa is large but information is scarce and thus it is unclear how big the problem really is. To gain insight into the magnitude and molecular epidemiology of ESBL-producing Enterobacteriaceae in East Africa a literature search was performed in PubMed on 31 July 2015 to retrieve articles with relevant information on ESBL.Methods and resultsMeta-analysis was performed to determine overall proportion estimate of ESBL-producing Enterobacteriaceae. A total of 4076 bacterial isolates were included in the analysis. The overall pooled proportion of ESBL-producing Enterobacteriaceae among included surveys done in East African hospitals was found to be 0.42 (95 % CI: 0.34–0.50). Heterogeneity (I2) between countries’ proportions in ESBL was significantly high (96.95 % and p < 0.001). The frequently detected genes encoding ESBL were CTX-M, TEM, SHV and OXA while the most infrequent reported genes were KPC and NDM.ConclusionThe available studies show a very wide variation in resistance due to ESBL between countries. This highlights a need for active surveillance systems which can help understand the actual epidemiology of ESBL, aid in formulating national or regional guidelines for proper screening of ESBL, and support developing standardized approaches for managing patients colonized with ESBL.Electronic supplementary materialThe online version of this article (doi:10.1186/s13756-016-0117-4) contains supplementary material, which is available to authorized users.

Extended spectrum beta-lactamase and AmpC producing Klebsiella pneumoniae: A therapeutic challenge

Klebsiella pneumoniae accounts for substantial proportion of nosocomial infections. Increasing multidrug resistance of these bacteria is posing a great threat to hospitalized patients as it results into limitation of therapeutic options. Therefore, the present study was undertaken with the following Aim and Objective :To know the burden of extended spectrum beta lactamase (ESBL) producing K. pneumoniae and coexistence of AmpC in these isolates using phenotypic methods in a newly established teaching hospital in Punjab, India. Materials and Methods: ESBL and AmpC screening and confirmation was done using phenotypic methods as per the Clinical and Laboratory Standards Institute (CLSI) guidelines in 200 clinical isolates of K. pneumoniae . Results: Out of 200 isolates of K. pneumoniae , 116 (58%) were ESBL producer and 84 (42%) were ESBL nonproducer. Of these 116 ESBL-positive isolates, 29 (25%) were coproducer of AmpC beta-lactamase. ESBL producing isolates were significantly more resistant to other group of antibiotics as compared to ESBL nonproducers. Discussion: High prevalence rate of ESBL producing K. pneumoniae was observed in our institute. MDR in these isolates was frequent, indicating the extensive injudicious use of antibiotics. Conclusion: Increasing prevalence of ESBL producing K. pneumoniae need to be checked to reduce the mortality and morbidity due to the infections caused by these strains.

Prevalence of ESBL in Escherichia coli Isolates Among ICU Patients in a Tertiary Care Hospital

Resistance to common antibiotics is a matter of grave concern in treating infections in hospital settings especially in Intensive Care Units (ICUs). One of the most commonly used and effective group of antibiotics, cephalosporins, exhibit resistance due to production of Extended Spectrum Beta- Lactamases (ESBLs). The prevalence of ESBL producing Escherichia coli (E.coli) has increased throughout the world and is a major cause of treatment failure in ICUs. As per our knowledge studies were not available on the prevalence of ESBL producing E.coli in ICUs of this region. To determine the prevalence of ESBLs among Escherichia coli isolates in ICUs of a tertiary care hospital. A cross sectional study was conducted over a period of 4 years (Sept 2011 to Sept 2015) in the Department of Microbiology, Kalinga Institute of Medical Sciences (KIMS), Bhubaneswar. Consecutive non-duplicate isolates of E.coli recovered from 6800 clinical samples of patients admitted to different Intensive Care Units (ICUs) were subjected to ESBL screening test and then to CLSI recommended Phenotypic Confirmatory Disc Diffusion Tests (PCDDT) for ESBL production determination. Out of 6800 samples, 1038 were E.coli isolates and 452(44%) were resistant to third generation cephalosporins. ESBL producing Escherichia coli among them were 276 (61.1%). Paediatric ICU showed the highest prevalence of ESBL E.coli at 80.9%. The highest prevalence of ESBL E.coli was in urine samples (82.6%) followed by pus (9.8%). The most effective antibiotic for ESBL producers was imipenem (96.7% sensitive), followed by amikacin (88.4%) and piperacillin- tazobactum (87%). This study has highlighted the high prevalence of ESBL producing E.coli in the ICUs of our hospital. An in depth analysis of their antibiogram will be helpful in formulating the antibiotic policy and prevent spread of ESBL strains. It is recommended that ESBL testing should be done routinely to curtail antibiotic resistance and to effectively implement infection control measures.

ESBL producing Pseudomonas aeruginosa in clinical specimens: Is it a scary nightmare or paper tiger?

Background: Pseudomonas aeruginosa well known as opportunistic pathogen, has been implicated in life threatening nosocomial infections in recent years. This can be attributable to acquired resistance by plasmid mediated different types of extended spectrum beta lactamases(ESBL). The present study was undertaken to detect the ESBL production of Pseudomonas aeruginosastrains and analyze their susceptibility pattern. Methods: Various clinical specimens received in our laboratory were processed and Pseudomonas aeruginosa was identified as per standard microbiological procedure. A total of 132 clinical isolates of Pseudomonas aeruginosa identified during the study period were included in the study. All isolates were subjected for ESBL screening test. Potential ESBL producer was then subjected for ESBL Phenotypic confirmatory test –Disc Diffusion method(PCDDT). Antimicrobial susceptibility test was performed by Kirby – Bauer disc diffusion method on all confirmed isolates by PCDDT method as per Clinical Laboratory Standard Institute (CLSI 2016) guidelines. Results: By phenotypic confirmatory method, the frequency of occurrence of ESBL among the isolates identified was 21.96% (n = 29).The highest number of ESBL producers was obtained from urine samples(27.7%) followed by respiratory infection (23.68%) and wound infection (22.95%). In-vitro susceptibility of ESBL producers revealed high level of resistance to third generation cephalosporin. Low resistance was observed to Imipenem (3.4%) and Piperacillin – Tazobactam (13.79%). Conclusion: Our study highlights the unique challenge imposed by Pseudomonas aeruginosa as the therapeutic choices are limited by ESBL production. To overcome this issue, we recommend routine ESBL detection and surveillance of antibiotic resistance in hospital settings. Keywords: Pseudomonas aeruginosa, ESBL, Third generation cephalosporins, Imipenem, Urine, ESBL Screening test

Superintendence of antimicrobial resistance observed in bacterial flora isolated from human faecal carriage in Vellore, India.

A frequent cross-sectional study was conducted to determine the patterns of antimicrobial resistance in 296 bacterial strains isolated from in-patient faecal samples of Government Vellore Medical College and Hospital, Vellore. Isolation and identification of bacterial strains were done using enrichment media, selective media, and biochemical tests. Antimicrobial susceptibility testing by the disc diffusion method and minimal inhibitory concentration method was conducted and the strains were subjected to extended spectrum beta-lactamases screening. Antibiotic sensitivity pattern of Staphylococcus spp. showed oxacillin resistance. Almost all the strains were sensitive to linezolid, vancomycin, gentamycin and chloramphenicol. In gram negative isolates ciprofloxacin and tobramycin showed better sensitivity and ceftazidime showed a higher percentage of resistance by MIC. Out of 250 isolates, Enterobacteriaceae showed positive for 86/250, 82/250 and 94/250 isolates and 3/10, 4/10 and 4/10 non-Enterobacteriaceae isolates were found to be positive for CTX-M gene, TEM gene and SHV gene, respectively. This study helps to assess/analyse the relation between the spectrum of microorganisms present in various grades of faecal carriage and their susceptibility pattern in this part of the Vellore town.

Extended-spectrum beta-lactamase-producing Enterobacteriaceae in hospital urinary tract infections: incidence and antibiotic susceptibility profile over 9years.

Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are an increasing concern regarding antibiotic resistance and their potential to cause serious infections which are difficult to treat. The purpose of this surveillance programme was to assess the incidence of ESBL in adults amongst urinary isolates, identify risk factors, and detail the antibiotic susceptibility profile in order to guide empirical treatment. From 2006 to 2014, we reviewed 21,414 positive urine cultures for E. coli and Klebsiella sp. from a University hospital in the UK and found 1420 ESBL-positive specimens. Susceptibility testing was performed by British Society of Antimicrobial Chemotherapy disc diffusion testing. ESBL screening was performed on samples resistant to cefpodoxime and confirmed by double disc diffusion (Oxoid Ltd, Basingstoke, UK). Patient gender, age, inpatient status, and catheterisation were assessed as risk factors. ESBL production amongst E. coli urine cultures increased 44%, from 4.6 to 6.6% of all E. coli isolates. ESBL-positive organisms were associated with increases in drug resistance, particularly amongst fluoroquinolones, trimethoprim, and cephalexin. Multidrug resistance was a feature with 75% of ESBL+ Klebsiella sp.-resistant ≥6 antibiotic classes. ESBL producers remained largely susceptible to carbapenems. Male gender, urinary catheterisation, inpatient status, and increasing age were identified as risk factors for ESBL infection or colonisation. We demonstrate that the incidence of ESBL-producing E. coli in urine cultures is increasing and that such isolates are multidrug resistant. Carbapenems and nitrofurantoin for E. coli infections remain effective, which may guide empirical antibiotic therapy.

Extended Spectrum Beta Lactamases Detection and Multiple Antibiotic Resistance Indexing of Escherichia Coli from Urine Samples of Patients from a Referral Hospital of Eastern Nepal

Background: Escherichia coli is the most common causative agent of urinary tract infection. Antibiotic resistance among uropathogens has become a prominent public health problem. Multidrug resistance bacteria have limited the therapeutic possibilities by producing Extended Spectrum Beta Lactamases (ESBL). Objective: Since routine monitoring of ESBL producers are not conducted in clinical laboratories their true prevalence is still unknown. So the objective of this research was to assess multiple antibiotic resistance (MAR) indices and determine ESBL production among Escherichia coli isolated from urine samples. Methods: Standard microbiological techniques and antibiotic sensitivity test were performed by Kirby Bauer disc diffusion method to identify E. coli. ESBL screening was done by using Ceftriaxone, Aztreonam, Cefotaxime, Ceftazidime and Cefpodoxime whereas confirmation by combined disc assay. SPSS 16 software was used to analyze data. Results: 86.95% E. coli isolates were MDR strains. 27 isolates had multiple antibiotic resistance (MAR) index of 0.2 and 5 isolates had MAR index of 0.7. E. coli isolates showed higher degree of resistance towards Amoxicillin (100%) while 100% were sensitive towards Gentamicin followed by Nitrofurantoin (62.31%). The reliable screening agent for ESBL detection with sensitivity 100% and positive predictive value of 80% was Cefotaxime. Combined disc assay detected 12/69 (17.31%) of E. coli isolates as confirmed ESBL producers. Conclusion: The ubiquity of ESBL-producing E. coli was observed emphasizing the necessity of regular surveillance of ESBL producing clinical isolates in clinical samples to minimize multi-drug resistance strains and avert the ineffectiveness of antimicrobial agent for good health practices.\Int J Appl Sci Biotechnol, Vol 3(3): 423-426

Outbreaks of extended spectrum beta-lactamase-producing Enterobacteriaceae in neonatal intensive care units: a systematic review

ObjectiveTo establish the number of outbreaks of extended spectrum beta-lactamase (ESBL) producing organisms in neonatal intensive care units (NICUs), to determine causes, mortality rates, proportions of infants colonised and infected...

Antibiotic Susceptibility Pattern of Extended Spectrum Betalactamase (ESBL) Producers and other Bacterial Pathogens in Kano, Nigeria

Purpose: To evaluate the antibiotic susceptibility pattern of various bacterial pathogens including extended spectrum betalactamase (ESBL) producers in Kano, Nigeria. Method: A total of 604 consecutive clinical samples obtained from Aminu Kano Teaching Hospital (AKTH), Kano between January and July 2010 were analyzed for bacterial pathogens using standard microbiological techniques for the isolation and identification of pathogens. Antibiotics susceptibility tests including, ESBL screening and confirmation, were carried out by disc diffusion technique using Clinical Laboratory Standard Institute (CLSI) criteria. Results: Ten different types of bacteria genera were observed from nine different clinical samples. E. coli was the most frequently isolated bacteria (30.5 %) followed by Staphylococcus aureus (21.3 %). ESBL producers showed high-level resistance against the quinolones, aminoglycoside and cotrimoxazole but were sensitive to carbapenems and levofloxaccin. Non-ESBL organisms showed increased resistance to amoxicillin-clavulanate, ceftazidime, cotrimoxazole, tetracycline and amoxycillin. The prevalence of ESBL producers was 12.8 %. E. coli , Klebsiella pneumonia and Pseudomonas aeruginosa showed ESBL production of 17.3, 14.9 and 10.0 %, respectively. Conclusion: The findings of this study suggest that regular surveys should be carried out in this locality to provide baseline data that would always be of clinical relevance in the treatment of patients and to detect the emergence of multiple antibiotic resistance strains. Keywords: Antibiotic Susceptibility, Multiple antibiotic Resistance, Extended Spectrum Betalactamase, Bacterial Pathogens

Frequency of extended spectrum β-lactamase producing urinary isolates of Gram-negative bacilli among patients seen in a multispecialty hospital in Vellore district, India.

Extended-spectrum beta-lactamase (ESBL) producing strains of Coliform bacilli are on the rise and present a major threat especially in India. We assessed the frequency of ESBL producers among urinary isolates from patients presenting urinary tract infections. ESBL screening was done using Double Disk Synergy Test (DDST) and confirmed using E-test and Polymerase Chain Reaction (PCR). With E-test, 92.2% were positive for ESBL. In PCR, 100% strains were positive for any of the three gene targets tested. CTX-M was positive in majority of the strains followed by TEM and SHV. Two (3.22%) strains were positive for all the three genes; 21% strains were positive for both TEM and CTX-M genes. There was no statistically significant difference in the findings of E-test and PCR testing in the determination of ESBL producers (Fisher exact test P = 0.15). The strength of agreement between them was 'fair' (k = 0.252). Continuous monitoring of ESBL producers among Indian strains is important to rationalize the antibiotic policy to be followed.

Prevalence and distribution of beta-lactamase coding genes in third-generation cephalosporin-resistant Enterobacteriaceae from bloodstream infections in Cambodia.

Resistance to third-generation cephalosporins in Gram-negative bacteria is emerging in Asia. We report the prevalence and distribution of extended-spectrum beta-lactamase (ESBL), AmpC beta-lactamase and carbapenemase-coding genes in cefotaxime-resistant Enterobacteriaceae isolates from bloodstream infections (BSI) in Cambodia. All Enterobacteriaceae isolated from BSI in adult patients at Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia (2007–2010) were assessed. Antimicrobial susceptibility testing was carried out by disc diffusion and MicroScan according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Screening for ESBL, plasmidic AmpC and carbapenemase-coding genes was performed by multiplex polymerase chain reaction (PCR) sequencing assays. Identification of the ST131 clone was performed in all CTX-M-positive Escherichia coli, using PCR targeting the papB gene. Out of 183 Enterobacteriaceae, 91 (49.7 %) isolates (84 BSI episodes) were cefotaxime-resistant: E. coli (n = 68), Klebsiella pneumoniae (n = 17) and Enterobacter spp. (n = 6). Most episodes were community-acquired (66/84; 78.3 %). ESBLs were present in 89/91 (97.8 %) cefotaxime-resistant isolates: 86 (96.6 %) were CTX-M, mainly CTX-M-15 (n = 41) and CTX-M-14 (n = 21). CTX-M of group 1 were frequently associated with TEM and/or OXA-1/30 coding genes and with phenotypic combined resistance to ciprofloxacin, sulphamethoxazole–trimethoprim and gentamicin (39/50, 78.0 %). Plasmidic AmpC (CMY-2 and DHA-1 types) were found alone (n = 2) or in combination with ESBL (n = 4). Eighteen E. coli isolates were identified as B2-ST131-O25B: 11 (61.1 %) carried CTX-M-14. No carbapenemase-coding genes were detected. ESBL among Enterobacteriaceae from BSI in Cambodia is common, mainly associated with CTX-M-15 and CTX-M-14. These findings warrant urgent action for the containment of antibiotic resistance in Cambodia.

Performance of extended spectrum beta lactamases (ESBL) screening agar in various clinical specimens

Performance of extended spectrum beta lactamases (ESBL) screening agar in various clinical specimens

Prevalence of blaCTX-M gene in multi-resistant Escherichia coli isolated from Urinary Tract Infections, Tehran, Iran

Background: The emergence and increase in the incidence of Extended-spectrum beta lactamase (ESBL) producing Escherichia coli (E. coli) has become an emerging challenge especially in hospitalized patients with urinary tract infection (UTI). The aim of the present study was to survey the frequency of bla CTX-M genotype in ESBL producing E. coli isolated from hospitalized patients with urinary tract infection and determination of their antibiotic resistance pattern. Materials and Methods: A total of 135 E. coli isolates were collected and isolated from patients with UTI. The isolates were subjected to confirmatory phenotype tests for the presence of ESBL. 75 E. coli isolates were confirmed as ESBL-positive by double disc synergy test. In vitro susceptibility of ESBL isolates to 15 antimicrobial agents amoxicillin, penicillin, ceftazidime, cefotaxime, cefoxitin, ceftriaxone, cefixime, cephalexin, co-trimoxazole, gentamicin, nalidixic acid, ciprofloxacin, nitrofurantoin, amikacin, and imipenem was performed by Kirby-Bauer’s Disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI, 2012) guideline. PCR method was used to identify bla CTX-M gene in 75 ESBL positive strains. Results: PCR and sequence analysis showed that 75 (55.5%) isolates produced bla CTX-M genes. In vitro susceptibility of ESBL producing E. coli showed that all of them were resistant to amoxicillin and penicillin. The rates of resistance to the majority of tested antibiotics varied among 61% to 100 %, with the exception of amikacin (14.7%) and imipenem (2.7%). Our results showed that the frequency of bla CTX-M was strikingly high (93.3%) in patients with UTI. Conclusion: These data confirmed that the frequency of bla CTX-M genes was high among E. coli isolated from patients with UTI. The trend of multidrug-resistant profile has been associated with bla CTX-M gene is alarming. Therefore, it is very important to establish a routine screening of ESBL in clinical isolates to prevent dissemination of resistant isolates in health care settings.

Molecular characterisation of Escherichia coli from dead broiler chickens with signs of colibacillosis and ready-to-market chicken meat in the West Bank

1. The aim of this work was to compare a group of virulence-associated characteristics of Escherichia coli isolates from broiler chickens that had died with signs of colibacillosis against E. coli isolates from ready-to-market chicken meat in the West Bank.2. The isolates were investigated to determine the virulence factor (VF) profile, phylogenetic group and the presence of extended-spectrum beta-lactamase (ESBL). A total of 66 avian pathogenic E. coli (APEC) strains from different affected broiler farms and 21 E. coli isolates from ready-to-market chicken carcasses (hereinafter called meat strains) from 8 slaughter houses were analysed.3. The overall content of VFs was significantly higher (P < 0.05) among APEC strains, with over 75% of APEC strains having ≥4 VFs, while over 75% of the meat strains had <4 VFs. The VFs iss, astA and iucD were frequently detected in APEC and meat strains, whereas cvi, papC, vat, tsh and irp2 occurred more significantly in APEC strains. Phylogenetic typing showed that 67% of the meat strains belonged to group B2. Phylogroup D was predominant (50%) in the APEC strains. Using double disc diffusion and polymerase chain reaction (PCR), 10.6% of the APEC and 9.5% of the meat strains were determined to be ESBL positive.4. Our findings show that the VFs papC, vat, irp2 and to a lesser extent tsh and cvi are significantly more prevalent in APEC strains. The results demonstrate that chicken meat can be contaminated with APEC strains (≥4 VF). A significant percentage of the meat strains fall in the B2 group, which is a phylogroup largely associated with human pathogenic ExPEC strains. The results of ESBL screening indicated that broiler chicken products in Palestine represent a potential reservoir of ESBL genes and therefore could be considered a possible public health risk.

Microbial resistance and frequency of extended-spectrum beta-lactamase (ESBL) in isolated from blood cultures

Introduction: The emergence and spread of isolated carriers of extended-spectrum beta-lactamase (ESBL) have complicated the treatment of nosocomial infections, since its production is not easily identified by the sensitivity tests, routinely performed in clinical laboratories, leading to difficulties in the hospital control of resistant microorganisms and antibiotics misuse. Objective: The objective of this study was to analyze the resistance profile and the frequency of ESBL in Gram-negative bacteria isolated from blood cultures. A hundred bacterial samples from blood cultures of adult patients were analyzed, which were phenotypically identified by biochemical tests of carbohydrates fermentation and submitted to determination of the resistance profile by disc diffusion test and ESBL screening by disc approximation and disc replacement methods. Results: Among the bacterial samples tested, 30 were identified as Gram-negative bacteria, predominantly by Proteus mirabilis, Pantoea agglomerans, and Escherichia coli. Of these, 73.33% were positive for the detection of ESBL by phenotypic tests, and was found mainly in Pantoea agglomerans, Proteus mirabilis, and Enterobacter cloacae. Conclusion: The increase in the occurrence of ESBL in different Enterobacteriaceae shows the importance of the amplification of detection in other species than Escherichia coli or Klebsiella sp., so that the assistance to the patient is not restrained, since these resistant bacteria cannot be detected by the laboratories. Considering the frequency of ESBL in this study, we highlight the importance of its detection, aiming to its contribution to the development of improvements in the health care policies of hospitals.