Cluster analysis of resistance combinations in Escherichia coli from different human and animal populations in Germany 2014-2017

Abstract Recent findings on Antibiotic Resistance (AR) have brought renewed attention to the comparison of data on AR from human and animal sectors. This is however, a major challenge since the data is not harmonized. This study performs a comparative analysis of data on resistance combinations in Escherichia coli (E. coli) from different routine surveillance and monitoring systems for human and different animal populations in Germany. Data on E. coli isolates were collected between 2014 and 2017 from human clinical isolates, non-clinical animal isolates from food-producing animals and food, and clinical animal isolates from food-producing and companion animals from national routine surveillance and monitoring for AR in Germany. Sixteen possible resistance combinations to four antibiotics - ampicillin, cefotaxime, ciprofloxacin and gentamicin – for these populations were used for hierarchical clustering (Euclidian and average distance). All analyses were performed with the software R 3.5.1 (Rstudio 1.1.442). Data of 333,496 E. coli isolates and forty-one different human and animal populations were included in the cluster analysis. Three main clusters were detected. Within these three clusters, all human populations (intensive care unit (ICU), general ward and outpatient care) showed similar relative frequencies of the resistance combinations and clustered together. They demonstrated similarities with clinical isolates from different animal populations and most isolates from pigs from both non-clinical and clinical isolates. Isolates from healthy poultry demonstrated similarities in relative frequencies of resistance combinations and clustered together. However, they clustered separately from the human isolates. All isolates from different animal populations with low relative frequencies of resistance combinations clustered together and likewise separately from the human populations. Cluster analysis has been able to demonstrate the linkage among human isolates and isolates from various animal populations based on the resistance combinations. Further analyses based on these findings might promote a better one-health approach for AR in Germany.

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Cluster analysis of resistance combinations in Escherichia coli from different human and animal populations in Germany 2014-2017

PLoS ONE ◽

10.1371/journal.pone.0244413 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0244413

Author(s):

Beneditta Suwono ◽

Tim Eckmanns ◽

Heike Kaspar ◽

Roswitha Merle ◽

Benedikt Zacher ◽

...

Keyword(s):

Escherichia Coli ◽

Cluster Analysis ◽

One Health ◽

Average Distance ◽

Companion Animals ◽

Clinical Isolates ◽

Human Populations ◽

Animal Populations ◽

Routine Surveillance ◽

Animal Isolates

Recent findings on Antibiotic Resistance (AR) have brought renewed attention to the comparison of data on AR from human and animal sectors. This is however a major challenge since the data is not harmonized. This study performs a comparative analysis of data on resistance combinations in Escherichia coli (E. coli) from different routine surveillance and monitoring systems for human and different animal populations in Germany. Data on E. coli isolates were collected between 2014 and 2017 from human clinical isolates, non-clinical animal isolates from food-producing animals and food, and clinical animal isolates from food-producing and companion animals from national routine surveillance and monitoring for AR in Germany. Sixteen possible resistance combinations to four antibiotics—ampicillin, cefotaxime, ciprofloxacin and gentamicin–for these populations were used for hierarchical clustering (Euclidian and average distance). All analyses were performed with the software R 3.5.1 (Rstudio 1.1.442). Data of 333,496 E. coli isolates and forty-one different human and animal populations were included in the cluster analysis. Three main clusters were detected. Within these three clusters, all human populations (intensive care unit (ICU), general ward and outpatient care) showed similar relative frequencies of the resistance combinations and clustered together. They demonstrated similarities with clinical isolates from different animal populations and most isolates from pigs from both non-clinical and clinical isolates. Isolates from healthy poultry demonstrated similarities in relative frequencies of resistance combinations and clustered together. However, they clustered separately from the human isolates. All isolates from different animal populations with low relative frequencies of resistance combinations clustered together. They also clustered separately from the human populations. Cluster analysis has been able to demonstrate the linkage among human isolates and isolates from various animal populations based on the resistance combinations. Further analyses based on these findings might support a better one-health approach for AR in Germany.

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Cluster analysis of resistance combinations in Escherichia coli from different human and animal populations in Germany 2014-2017

10.21203/rs.3.rs-30292/v1 ◽

2020 ◽

Author(s):

Beneditta Suwono ◽

Tim Eckmanns ◽

Heike Kaspar ◽

Roswitha Merle ◽

Benedikt Zacher ◽

...

Keyword(s):

Escherichia Coli ◽

Cluster Analysis ◽

Average Distance ◽

Companion Animals ◽

Clinical Isolates ◽

Human Populations ◽

E Coli ◽

Animal Populations ◽

Routine Surveillance ◽

Resistance Patterns

Abstract Background Recent findings on Antibiotic Resistance (AR) have brought renewed attention to the comparison of data on AR from human and animal sectors. This is however, a major challenge since the data is not harmonized. This study performs a comparative analysis of phenotypical AR data from different routine surveillance and monitoring systems in Germany. Escherichia coli data were used as a model to describe the similarities based on the resistance patterns in human and different animal populations in Germany. Method: Data on E. coli isolates were collected from 2014 to 2017 from human clinical isolates, non-clinical isolates from food-producing animals and food, and clinical isolates from food-producing and companion animals from national routine surveillance and monitoring for AR in Germany. Four antibiotics - ampicillin, cefotaxime, ciprofloxacin and gentamicin - were chosen for the analysis. Resistant isolates were defined according to EUCAST clinical breakpoints for humans. Based on the 16 possible resistance combinations to these four antibiotics, cluster analysis was performed using hierarchical clustering with Euclidian and average distance. All analyses were performed with the software “R”. Result Data of 333,496 E. coli isolates were included in this study. Forty-one different human and animal populations were included in the cluster analysis. Three main clusters were detected. Within these three clusters, all human populations (intensive care unit (ICU), general ward and outpatient care) showed similar relative frequencies of the resistance combinations and clustered together. They demonstrated similarities with clinical isolates from different animal populations and most isolates from pigs from both non-clinical and clinical isolates. Isolates from healthy poultry demonstrated similarities in relative frequencies of resistance combinations and clustered together. However, they clustered separately from the human isolates. All isolates from different animal populations with low relative frequencies of resistance combinations clustered together and likewise separately from the human populations. Conclusion Cluster analysis facilitated the comparison of phenotypical AR data across human and animal sectors. It indicated linkage among human isolates and with isolates from various animal populations based on the resistance combinations in E. coli. Further analyses based on these findings might promote a better one-health approach for AR in Germany.

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Virulence Properties of mcr-1-Positive Escherichia coli Isolated from Retail Poultry Meat

Microorganisms ◽

10.3390/microorganisms9020308 ◽

2021 ◽

Vol 9 (2) ◽

pp. 308

Author(s):

Michaela Kubelová ◽

Ivana Koláčková ◽

Tereza Gelbíčová ◽

Martina Florianová ◽

Alžběta Kalová ◽

...

Keyword(s):

Escherichia Coli ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Poultry Meat ◽

Human Populations ◽

E Coli ◽

Antimicrobial Resistance Genes ◽

Mlst Type ◽

On Line ◽

Sequence Types

The great plasticity and diversity of the Escherichia coli genome, together with the ubiquitous occurrence, make E. coli a bacterium of world-wide concern. Of particular interest are pathogenic strains and strains harboring antimicrobial resistance genes. Overlapping virulence-associated traits between avian-source E. coli and human extraintestinal pathogenic E. coli (ExPEC) suggest zoonotic potential and safety threat of poultry food products. We analyzed whole-genome sequencing (WGS) data of 46 mcr-1-positive E. coli strains isolated from retail raw meat purchased in the Czech Republic. The investigated strains were characterized by their phylogroup—B1 (43%), A (30%), D (11%), E (7%), F (4%), B2 (2%), C (2%), MLST type, and serotype. A total of 30 multilocus sequence types (STs), of which ST744 was the most common (11%), were identified, with O8 and O89 as the most prevalent serogroups. Using the VirulenceFinder tool, 3 to 26 virulence genes were detected in the examined strains and a total of 7 (15%) strains met the pathogenic criteria for ExPEC. Four strains were defined as UPEC (9%) and 18 (39%) E. coli strains could be classified as APEC. The WGS methods and available on-line tools for their evaluation enable a comprehensive approach to the diagnosis of virulent properties of E. coli strains and represent a suitable and comfortable platform for their detection. Our results show that poultry meat may serve as an important reservoir of strains carrying both virulence and antibiotic resistance genes for animal and human populations.

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Mechanistic insights into synergy between nalidixic acid and tetracycline against clinical isolates of Acinetobacter baumannii and Escherichia coli

Communications Biology ◽

10.1038/s42003-021-02074-5 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Amit Gaurav ◽

Varsha Gupta ◽

Sandeep K. Shrivastava ◽

Ranjana Pathania

Keyword(s):

Escherichia Coli ◽

Acinetobacter Baumannii ◽

Nalidixic Acid ◽

Bacterial Infections ◽

Clinical Isolates ◽

Hospital Environment ◽

Infection Model ◽

Drug Resistant ◽

E Coli

AbstractThe increasing prevalence of antimicrobial resistance has become a global health problem. Acinetobacter baumannii is an important nosocomial pathogen due to its capacity to persist in the hospital environment. It has a high mortality rate and few treatment options. Antibiotic combinations can help to fight multi-drug resistant (MDR) bacterial infections, but they are rarely used in the clinics and mostly unexplored. The interaction between bacteriostatic and bactericidal antibiotics are mostly reported as antagonism based on the results obtained in the susceptible model laboratory strain Escherichia coli. However, in the present study, we report a synergistic interaction between nalidixic acid and tetracycline against clinical multi-drug resistant A. baumannii and E. coli. Here we provide mechanistic insight into this dichotomy. The synergistic combination was studied by checkerboard assay and time-kill curve analysis. We also elucidate the mechanism behind this synergy using several techniques such as fluorescence spectroscopy, flow cytometry, fluorescence microscopy, morphometric analysis, and real-time polymerase chain reaction. Nalidixic acid and tetracycline combination displayed synergy against most of the MDR clinical isolates of A. baumannii and E. coli but not against susceptible isolates. Finally, we demonstrate that this combination is also effective in vivo in an A. baumannii/Caenorhabditis elegans infection model (p < 0.001)

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Multidrug Resistance Dissemination in Escherichia coli Isolated from Wild Animals: Bacterial Clones and Plasmid Complicity

Microbiology Research ◽

10.3390/microbiolres12010009 ◽

2021 ◽

Vol 12 (1) ◽

pp. 123-137

Author(s):

Carolina Sabença ◽

Gilberto Igrejas ◽

Patrícia Poeta ◽

Frédéric Robin ◽

Richard Bonnet ◽

...

Keyword(s):

Escherichia Coli ◽

Epidemiological Data ◽

Generation Cephalosporin ◽

Wild Animals ◽

Variable Regions ◽

E Coli ◽

Wild Fauna ◽

Long Read ◽

Sequence Types ◽

Animal Isolates

Objectives. Epidemiological data concerning third-generation cephalosporin (3GC) resistance in wild fauna are scarce. The aim of this study was to characterize the resistance genes, their genetic context, and clonal relatedness in 17 Escherichia coli resistant to 3GC isolated from wild animals. Methods. The isolates were characterized by short-read whole genome sequencing, and long-read sequencing was used for the hybrid assembly of plasmid sequences. Results. The 3GC resistance gene most identified in the isolates was the extended-spectrum β-lactamases (ESBL)-encoding gene blaCTX-M-1 (82.3%), followed by blaCTX-M-32 (5.9%), blaCTX-M-14 (5.9%), and blaSHV-12 (5.9%). E. coli isolates mainly belonged to the sequence types (STs) rarely reported from humans. The single nucleotide polymorphism (SNP)-based typing showed that most E. coli genomes from wild animals (wild boars, birds of prey, and buzzards) formed clonal clusters (<5 SNPs), showing a clonal dissemination crossing species boundaries. blaCTX-M-1-harboring IncI1-ST3 plasmid was the predominant ESBL-encoding plasmid (76.4%) in wild animal isolates. Plasmid comparison revealed a 110-kb self-transferable plasmid consisting of a conserved backbone and two variable regions involved in antimicrobial resistance and in interaction with recipient cells during conjugation. Conclusion. Our results highlighted the unexpected clonal dissemination of blaCTX-M-1-encoding clones and the complicity of IncI1-ST3 plasmid in the spread of blaCTX-M-1 within wild fauna.

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Single Clinical Isolates from Acute Uncomplicated Urinary Tract Infections Are Representative of Dominant In Situ Populations

mBio ◽

10.1128/mbio.01064-13 ◽

2014 ◽

Vol 5 (2) ◽

Cited By ~ 18

Author(s):

Dana Willner ◽

Serene Low ◽

Jason A. Steen ◽

Narelle George ◽

Graeme R. Nimmo ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Clinical Isolates ◽

Content Type ◽

E Coli ◽

Strain Diversity ◽

Amplicon Pyrosequencing ◽

Culture Independent ◽

Tract Infections

ABSTRACTUrinary tract infections (UTIs) are one of the most commonly acquired bacterial infections in humans, and uropathogenicEscherichia colistrains are responsible for over 80% of all cases. The standard method for identification of uropathogens in clinical laboratories is cultivation, primarily using solid growth media under aerobic conditions, coupled with morphological and biochemical tests of typically a single isolate colony. However, these methods detect only culturable microorganisms, and characterization is phenotypic in nature. Here, we explored the genotypic identity of communities in acute uncomplicated UTIs from 50 individuals by using culture-independent amplicon pyrosequencing and whole-genome and metagenomic shotgun sequencing. Genus-level characterization of the UTI communities was achieved using the 16S rRNA gene (V8 region). Overall UTI community richness was very low in comparison to other human microbiomes. We strain-typedEscherichia-dominated UTIs using amplicon pyrosequencing of the fimbrial adhesin gene,fimH. There were nine highly abundantfimHtypes, and each UTI sample was dominated by a single type. Molecular analysis of the corresponding clinical isolates revealed that in the majority of cases the isolate was representative of the dominant taxon in the community at both the genus and the strain level. Shotgun sequencing was performed on a subset of eightE. coliurine UTI and isolate pairs. The majority of UTI microbial metagenomic sequences mapped to isolate genomes, confirming the results obtained using phylogenetic markers. We conclude that for the majority of acute uncomplicatedE. coli-mediated UTIs, single cultured isolates are diagnostic of the infection.IMPORTANCEIn clinical practice, the diagnosis and treatment of acute uncomplicated urinary tract infection (UTI) are based on analysis of a single bacterial isolate cultured from urine, and it is assumed that this isolate represents the dominant UTI pathogen. However, these methods detect only culturable bacteria, and the existence of multiple pathogens as well as strain diversity within a single infection is not examined. Here, we explored bacteria present in acute uncomplicated UTIs using culture-independent sequence-based methods.Escherichia coliwas the most common organism identified, and analysis ofE. colidominant UTI samples and their paired clinical isolates revealed that in the majority of infections the cultured isolate was representative of the dominant taxon at both the genus and the strain level. Our data demonstrate that in most cases single cultured isolates are diagnostic of UTI and are consistent with the notion of bottlenecks that limit strain diversity during UTI pathogenesis.

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Amdinocillin (Mecillinam) Resistance Mutations in Clinical Isolates and Laboratory-Selected Mutants of Escherichia coli

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.04819-14 ◽

2015 ◽

Vol 59 (3) ◽

pp. 1718-1727 ◽

Cited By ~ 58

Author(s):

Elisabeth Thulin ◽

Martin Sundqvist ◽

Dan I. Andersson

Keyword(s):

Escherichia Coli ◽

Clinical Isolates ◽

Cysteine Biosynthesis ◽

Resistance Mutations ◽

Content Type ◽

E Coli ◽

Major Mechanism ◽

Laboratory Selection ◽

Lactam Antibiotic ◽

Tract Infections

ABSTRACTAmdinocillin (mecillinam) is a β-lactam antibiotic that is used mainly for the treatment of uncomplicated urinary tract infections. The objectives of this study were to identify mutations that confer amdinocillin resistance on laboratory-isolated mutants and clinical isolates ofEscherichia coliand to determine why amdinocillin resistance remains rare clinically even though resistance is easily selected in the laboratory. Under laboratory selection, frequencies of mutation to amdinocillin resistance varied from 8 × 10−8to 2 × 10−5per cell, depending on the concentration of amdinocillin used during selection. Several genes have been demonstrated to give amdinocillin resistance, but here eight novel genes previously unknown to be involved in amdinocillin resistance were identified. These genes encode functions involved in the respiratory chain, the ribosome, cysteine biosynthesis, tRNA synthesis, and pyrophosphate metabolism. The clinical isolates exhibited significantly greater fitness than the laboratory-isolated mutants and a different mutation spectrum. ThecysBgene was mutated (inactivated) in all of the clinical isolates, in contrast to the laboratory-isolated mutants, where mainly other types of more costly mutations were found. Our results suggest that the frequency of mutation to amdinocillin resistance is high because of the large mutational target (at least 38 genes). However, the majority of these resistant mutants have a low growth rate, reducing the probability that they are stably maintained in the bladder. Inactivation of thecysBgene and a resulting loss of cysteine biosynthesis are the major mechanism of amdinocillin resistance in clinical isolates ofE. coli.

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Molecular survey of mcr1 and mcr2 plasmid mediated colistin resistance genes in Escherichia coli isolates of animal origin in Iran

BMC Research Notes ◽

10.1186/s13104-021-05519-6 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Kayhan Ilbeigi ◽

Mahdi Askari Badouei ◽

Hossein Vaezi ◽

Hassan Zaheri ◽

Sina Aghasharif ◽

...

Keyword(s):

Escherichia Coli ◽

Resistance Genes ◽

Companion Animals ◽

Multidrug Resistant ◽

Animal Origin ◽

Colistin Resistance ◽

E Coli ◽

High Level ◽

Farming Industry

Abstract Objectives The emergence of colistin-resistant Enterobacteriaceae from human and animal sources is one of the major public health concerns as colistin is the last-resort antibiotic for treating infections caused by multidrug-resistant Gram-negative bacteria. We aimed to determine the prevalence of the prototype widespread colistin resistance genes (mcr-1 and mcr-2) among commensal and pathogenic Escherichia coli strains isolated from food-producing and companion animals in Iran. Results A total of 607 E. coli isolates which were previously collected from different animal sources between 2008 and 2016 used to uncover the possible presence of plasmid-mediated colistin resistance genes (mcr-1 and mcr-2) by PCR. Overall, our results could not confirm the presence of any mcr-1 or mcr-2 positive E. coli among the studied isolates. It is concluded that despite the important role of food-producing animals in transferring the antibiotic resistance, they were not the main source for carriage of mcr-1 and mcr-2 in Iran until 2016. This study suggests that the other mcr variants (mcr-3 to mcr-9) might be responsible for conferring colistin resistance in animal isolates in Iran. The possible linkage between pig farming industry and high level of mcr carriage in some countries needs to be clarified in future prospective studies.

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SEPSIS MARKERS AND SENSITIVITY OF STAPHYLOCOCCUS AUREUS AND ESCHERICHIA COLI ISOLATES IN A GENERAL HOSPITAL SETTING

Vestnik ◽

10.53065/kaznmu.2021.86.69.013 ◽

2021 ◽

pp. 68-74

Author(s):

М.Е. Рамазанов ◽

В.Н. Сон ◽

М.Р. Рысулы ◽

С.Т. Турсуналиев ◽

Е.Б. Еспенбетов

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Hospital Setting ◽

Bloodstream Infections ◽

High Sensitivity ◽

Clinical Isolates ◽

Empiric Antibiotic Therapy ◽

E Coli ◽

Number Of Patients ◽

Empiric Antibiotic

Представлены результаты проспективного обследования 80 больных ГКБ №7 с бактериемией с октября 2019 года по февраль 2021 года из различных отделений госпиталя. Производилась оценки показателей маркеров сепсиса - пресепсина, прокальцитонина и С-реактивного белка (СРБ) в крови больных в динамике эмпирической терапии антимикробными препаратами (АМП). Наибольшее число больных с выявленной бактериемией находилось в отделении ОАРИТ - 39 пациентов, у 25 из них был диагностирован сепсис по шкале СЕПСИС III, вызванный известными патогенами Staphylococcus aureus (46,6%) и Escherichia coli (36,6%). Для эмпирического лечения применялись различные антибиотики: ампенициллин, амикацин, меропенем, цефотаксим, метрид, ципрофлоксацин, ципрокс, цефлокс, цефазолин, цефтриаксон, левофлоксацин. Уровни прокальцитонина составляют для больных с клиническими изолятами E. coli 20,8±3,1нг/мл, а для изолятов St. aureus 15,7±1,8 нг/мл. После терапии АМП наблюдается значительное снижение показателей до 1,43±0,6 и 2,3±0,9 нг/мл., что позволяет признать эффективность эмпирической антибиотикотерапии при инфекциях кровотока. Высокая чувствительность клинических изолятов Escherichia coli отмечена к препаратам группы карбапенемов - имипенему и меропенему (90,9%), низкая к эртапенему (72,7%). 100% чувствительность все изоляты показали по отношению к АМП из группы глицилциклинов - тигециклину, который структурно сходен с тетрациклинами. Высокой резистеностью клинические изоляты Staphylococcus aureus обладают к пенициллину (92,9%), липопептиду природного происхождения даптомицину (85,8%) и препарату из группы линкозамидов - клиндамицину (64,3%). The results of a prospective examination of 80 patients with bacteremia from October 2019 to February 2021 from various departments of the hospital are presented. The largest number of patients with detected bacteremia were in the OARIT department - 39 patients, 25 of them were diagnosed with sepsis according to the SEPSIS III scale, caused by known pathogens Staphylococcus aureus (46.6%) and Escherichia coli (36.6%). For empirical treatment, various antibiotics were used: ampenicillin, amikacin, meropenem, cefotaxime, metrid, ciprofloxacin, ciprox, ceflox, cefazolin, ceftriaxone, levofloxacin. Procalcitonin levels for patients with clinical E. coli isolates are 20.8 ± 3.1 ng / ml, and for St. aureus 15.7 ± 1.8 ng / ml. After AMP therapy, there is a significant decrease in indicators to 1.43 ± 0.6 and 2.3 ± 0.9 ng / ml, which makes it possible to recognize the effectiveness of empiric antibiotic therapy for bloodstream infections. High sensitivity of clinical isolates of Escherichia coli was noted to drugs of the carbapenem group - imipenem and meropenem (90.9%), low to ertapenem (72.7%). All isolates showed 100% sensitivity to AMPs from the glycylcycline group - tigecycline, which is structurally similar to tetracyclines. Clinical isolates of Staphylococcus aureus are highly resistant to penicillin (92.9%), natural lipopeptide daptomycin (85.8%), and a drug from the lincosamide group - clindamycin (64.3%).

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IDENTIFICATION OF AMPC Β-LACTAMASE-PRODUCING CLINICAL ISOLATES OF ESCHERICHIA COLI

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i12.21648 ◽

2017 ◽

Vol 10 (12) ◽

pp. 357

Author(s):

Tanushree Barua Gupta ◽

Malini Shariff ◽

Thukral Ss ◽

S.s Thukral

Keyword(s):

Escherichia Coli ◽

Detection Method ◽

Clinical Isolates ◽

Confirmatory Test ◽

Chain Reaction ◽

E Coli ◽

Resistance To Penicillin ◽

Polymerase Chain ◽

Third Generation Cephalosporins

Objective: Indiscriminate use of β-lactam antibiotics has resulted in the emergence of β-lactamase enzymes. AmpC β-lactamases, in particular, confer resistance to penicillin, first-, second-, and third-generation cephalosporins as well as monobactams and are responsible for antibiotic resistance in nosocomial pathogens. Therefore, this study was undertaken to screen nosocomial Escherichia coli isolates for the presence and characterization of AmpC β-lactamases. The study also envisaged on the detection of inducible AmpC β-lactamases and extended-spectrum β-lactamases (ESBLs) in AmpC β-lactamase-producing E. coli.Methods: A total of 102 clinical isolates of E. coli, were subjected to cefoxitin screening, and screen-positive isolates were further subjected to inhibitor-based detection method, phenotypic confirmatory test, disc antagonism test, polymerase chain reaction (PCR), and isoelectric focusing (IEF).Results: In this study, 33% of E. coli were resistant to cefoxitin, of which 35% were found to be positive for AmpC β-lactamase by inhibitor-based phenotypic test. Of the AmpC-positive isolates, 83% were positive for ESBLs, whereas 25% were producing inducible AmpC β-lactamases. PCR and IEF showed CIT and EBC types of AmpC β-lactamases present in the tested isolates.Conclusion: Our study showed the presence of inducible AmpC enzymes and ESBLs in E. coli isolates and PCR identified more isolates to be AmpC producers.

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