A Multicenter Study of Beta-Lactamase ResistantEscherichia coliandKlebsiella pneumoniaeReveals High Level Chromosome Mediated Extended SpectrumβLactamase Resistance in Ogun State, Nigeria

Abstract

As a result of the ever increasing problem of multiresistant bacteria, we instituted a surveillance program with the aim of identifying the basic molecular properties of ESBL in our environment. About 197 isolates ofEscherichia coliandKlebsiella pneumoniaewere selected and tested for ESBL production and antimicrobial susceptibility. Plasmid profiles were determined and curing ability was tested. ESBL prevalence was 26.4% for all isolates tested, withE. colihaving a greater proportion. There was absolute resistance to ampicilin, tetracycline, and co-trimaxole among tested isolates. There was above average susceptibility to the 2nd and 3rd generation cephalosporins. Plasmid profiles of tested isolates ranged from 9 kbp to 26 kbp with average of14.99±2.3 kbp forE. coliand20.98±1.8 kbpK. pneumoniae, 9.6% of ESBL positiveE. coliplasmids were cured, while 3.9% ofK. pneumoniaeplasmids were cured after treatment. The present study shows an upsurge in ESBL acquisition by gram negative bacteria and evidence of cocirculation of varying subtypes of ESBL with both plasmid transmissible and chromosome encoded subtypes. This calls for universal surveillance and more effort towards molecular epidemiology of this public health treatment.