PREVALENCE OF ESBL IN ESCHERICHIA COLI AND ITS ANTIBIOTIC RESISTANCE PATTERN FROM VARIOUS CLINICAL SAMPLES IN A TERTIARY CARE HOSPITAL

Pooja Prakash Chavan, Shanu Braj Kishor Sharma and Dr. G. S. Karande*

ABSTRACT

Background: E.coli is commonest cause of urinary tract infection. ESBLs are increasingly reported worldwide and possessing great epidemic potential. Plasmids coding for ESBLs carry additional β -lactamase genes as well as genes extending resistance to other antimicrobial classes. Therefore, phenotypic detection of ESBLs among Escherichia coli is important for epidemiological purposes as well as for limiting the spread of resistance mechanisms. Objective: To isolate and identify Escherichia coli from various clinical samples, assess the antimicrobial susceptibility pattern of the organisms isolated and to study the different methods of ESBL resistance among these isolates. Method: A total of 140 isolates of Escherichia coli from clinical samples such as pus, sputum, urine, blood, body fluids were collected during the study. This isolates were cultured and identified by standard procedure. Antibiotic susceptibility testing of Escherichia coli was done including third generation of cephalosporins and resistant were done by screening for ESBL producing Escherichia coli by Double disc synergy test (DDST) and Combined disc diffusion test (CDDT). Result: By screening test, out of 140 isolates of Escherichia coli 111(79.29%) were suspected to be an ESBL producer and 29 (21.71%) were suspected as non- ESBL producers. Those 111 isolates obtained by screening test were further preceded for phenotypic confirmatory test. The ESBL positive isolates obtained by combine disc diffusion test was 70(63.06%), and by double disc synergy test 64(57.66%). Conclusion: Most of Escherichia coli ESBL positive isolates were observed in urine specimen. Combined disc diffusion test is more effective than double disc diffusion test. So, CDDT being simple and cheaper method should be included in the microbiology laboratories as a routine test for early deduction of ESBL producing organisms in specimen from critically ill patients.

Keywords: E. coli, ESBL, Antibiotic susceptibility testing, UTI, OPD, IPD.