The prevalence of extended-spectrum beta-lactamase in environmental isolates of Enterobacter.

The incidence of extended-spectrum beta-lactamase (ESBL)-producing strains and multidrug-resistant strains of Enterobacter spp. isolated from the 1312 km long river Narmada was investigated. Out of the 57 isolates of Enterobacter, 73.68% were found to be ESBL producers including the isolates of E. taylorae and isolates of E. agglomerans, which have been characterized for the first time. All the isolates were found susceptible to the antibiotic imipenem. AmpC gene was found in all the Enterobacter strains tested. AmpC beta-lactamase-producing bacterial pathogens may cause major therapeutic failure if not detected and reported in time. It was seen that these enzymes are mainly chromosomally mediated along with several non-AmpC beta-lactamase.