Dataset Information

QRDR mutations, efflux system & antimicrobial resistance genes in enterotoxigenic Escherichia coli isolated from an outbreak of diarrhoea in Ahmedabad, India.

ABSTRACT: BACKGROUND & OBJECTIVES: Diverse mechanisms have been identified in enteric bacteria for their adaptation and survival against multiple classes of antimicrobial agents. Resistance of bacteria to the most effective fluoroquinolones have increasingly been reported in many countries. We have identified that most of the enterotoxigenic Escherichia coli (ETEC) were resistant to several antimicrobials in a diarrhoea outbreak at Ahmedabad during 2000. The present study was done to identify several genes responsible for antimicrobial resistance and mobile genetic elements in the ETEC strains. METHODS: Seventeen ETEC strains isolated from diarrhoeal patients were included in this study. The antimicrobial resistance was confirmed by conventional disc diffusion method. PCR and DNA sequencing were performed for the identification of mutation in the quinolone resistance-determining regions (QRDRs). Efflux pump was tested by inhibiting the proton-motive force. DNA hybridization assay was made for the detection of integrase genes and the resistance gene cassettes were identified by direct sequencing of the PCR amplicons. RESULTS: Majority of the ETEC had GyrA mutations at codons 83 and 87 and in ParC at codon 80. Six strains had an additional mutation in ParC at codon 108 and two had at position 84. Plasmid-borne qnr gene alleles that encode quinolone resistance were not detected but the newly described aac(6')-Ib-cr gene encoding a fluoroquinolne-modifying enzyme was detected in 64.7 per cent of the ETEC. Class 1 (intI1) and class 2 (intI2) integrons were detected in six (35.3%) and three (17.6%) strains, respectively. Four strains (23.5%) had both the classes of integrons. Sequence analysis revealed presence of dfrA17, aadA1, aadA5 in class 1, and dfrA1, sat1, aadA1 in class 2 integrons. In addition, the other resistance genes such as tet gene alleles (94.1%), catAI (70.6%), strA (58.8%), bla TEM-1 (35.2%), and aphA1-Ia (29.4%) were detected in most of the strains. INTERPRETATION & CONCLUSIONS: Innate gene mutations and acquisition of multidrug resistance genes through mobile genetic elements might have contributed to the emergence of multidrug resistance (MDR) in ETEC. This study reinforces the necessity of utilizing molecular techniques in the epidemiological studies to understand the nature of resistance responsible for antimicrobial resistance in different species of pathogenic bacteria.

SUBMITTER: Pazhani GP

PROVIDER: S-EPMC3181023 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

QRDR mutations, efflux system & antimicrobial resistance genes in enterotoxigenic Escherichia coli isolated from an outbreak of diarrhoea in Ahmedabad, India.

Pazhani G P GP Chakraborty S S Fujihara K K Yamasaki S S Ghosh A A Nair G B GB Ramamurthy T T

The Indian journal of medical research 20110801

<h4>Background & objectives</h4>Diverse mechanisms have been identified in enteric bacteria for their adaptation and survival against multiple classes of antimicrobial agents. Resistance of bacteria to the most effective fluoroquinolones have increasingly been reported in many countries. We have identified that most of the enterotoxigenic Escherichia coli (ETEC) were resistant to several antimicrobials in a diarrhoea outbreak at Ahmedabad during 2000. The present study was done to identify sever ...[more]

PMID: 21911975

Similar Datasets

Project description:BackgroundShigella and enterotoxigenic Escherichia coli (ETEC) are bacterial pathogens that are frequently associated with diarrhoeal disease, and are a significant cause of mortality and morbidity worldwide. The Global Burden of Diseases, Injuries, and Risk Factors study 2016 (GBD 2016) is a systematic, scientific effort to quantify the morbidity and mortality due to over 300 causes of death and disability. We aimed to analyse the global burden of shigella and ETEC diarrhoea according to age, sex, geography, and year from 1990 to 2016.MethodsWe modelled shigella and ETEC-related mortality using a Bayesian hierarchical modelling platform that evaluates a wide range of covariates and model types on the basis of vital registration and verbal autopsy data. We used a compartmental meta-regression tool to model the incidence of shigella and ETEC, which enforces an association between incidence, prevalence, and remission on the basis of scientific literature, population representative surveys, and health-care data. We calculated 95% uncertainty intervals (UIs) for the point estimates.FindingsShigella was the second leading cause of diarrhoeal mortality in 2016 among all ages, accounting for 212 438 deaths (95% UI 136 979-326 913) and about 13·2% (9·2-17·4) of all diarrhoea deaths. Shigella was responsible for 63 713 deaths (41 191-93 611) among children younger than 5 years and was frequently associated with diarrhoea across all adult age groups, increasing in elderly people, with broad geographical distribution. ETEC was the eighth leading cause of diarrhoea mortality in 2016 among all age groups, accounting for 51 186 deaths (26 757-83 064) and about 3·2% (1·8-4·7) of diarrhoea deaths. ETEC was responsible for about 4·2% (2·2-6·8) of diarrhoea deaths in children younger than 5 years.InterpretationThe health burden of bacterial diarrhoeal pathogens is difficult to estimate. Despite existing prevention and treatment options, they remain a major cause of morbidity and mortality globally. Additional emphasis by public health officials is needed on a reduction in disease due to shigella and ETEC to reduce disease burden.FundingBill & Melinda Gates Foundation.

Dataset Information

QRDR mutations, efflux system & antimicrobial resistance genes in enterotoxigenic Escherichia coli isolated from an outbreak of diarrhoea in Ahmedabad, India.

Publications

QRDR mutations, efflux system & antimicrobial resistance genes in enterotoxigenic Escherichia coli isolated from an outbreak of diarrhoea in Ahmedabad, India.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets