Determination of Incidence of Extended Spectrum Beta Lactamases (ESBL) Producing Gram Negative Bacilli at a Tertiary Care Hospital Serving a Rural Population

Extended spectrum beta lactamase (ESBL)-producing organisms pose unique challenge to clinical microbiologists, clinicians, infection control professionals and scientists. ESBLs are enzymes produced by some bacteria or germs that can make them resistant to certain antibiotics. ESBLs are enzymes capable of hydrolyzing penicillin, broadspectrum cephalosporins and monobactams that are generally derived from TEM and SHVtype enzymes. ESBLs are often located on plasmid that are transferable from strain to strain and between bacterial species.The present study was undertaken to determine the incidence, detect ESBL producers and study the antibiotic resistance pattern of gram negative bacilli (GNB) in clinical isolates of different specimens in a tertiary care hospital of rural West Bengal so that more effective treatment protocols can be planned. In this hospital based prospective study, 855 samples collected over a two month period were analyzed phenotypically according to CLSI specifications for GNB isolates which produced ESBL. 126 isolates proved to be GNB out of which 19 were ESBL producers by CLSI confirmatory tests. The majority, were Escherichia coli followed by Klebsiella spp, Pseudomonas spp and others. Approximately 13% of the isolates were ESBL producers which is a lower figure than the other hospitals of this country and some other parts of the world. Intervention with proper antibiotic use and awareness will help in preventing higher resistance in the hospital isolates..