Phenotypic and molecular characterisation of blaCTX-M ESBL gene in clinical isolates of Enterobacteriaceae in a tertiary care

Abstract

Members of the family cause mild to life-threatening infectious diseases in Enterobacteriaceae the recent past all the overworld. ESBL producing Enterobacteriaceae poses a threat to both community and hospital settings, which leads to empirical treatment failure, increasing the rate of morbidity and mortality. A cross-sectional convenient sampling study was done to detect and characterise CTX-M genes among extended spectrum β-lactamases (ESBLs) producing Enterobacteriaceae from clinical isolates in a tertiary care centre A total of 200 isolates of Enterobacteriaceae were collected from var- ious clinical samples. ESBLs production was phenotypically detected by screening with ceftazidime, cefotaxime and cefepime, and then confirmed by disk combination method and multiplex PCR. Escherichia coli was the most predominant 87 (43.5%) isolate, followed by Klebsiella pneumonia 72(36%), Klebsiella oxytoca 15(7.5%), Proteus species 10 (5%), Enterobacter species 5 (2.5%) and Citrobacter species 1 (2.5%). ESBLs were detected by phenotypic confirmatory combination method in 144 (72%) isolates 197/200 (98.5%) were ESBLs producers were positive for blaCTX-M genes by PCR. The study highlights the high prevalence of blaCTX-M genes among the Enterobacteriaceae. CTX-M group 1 was the most commonly encountered CTX-M group in our study.