Phenotypic and Molecular Characterization of Multidrug - Resistant Uropathogenic Escherichia coli

Background: Urinary tract infection (UTI) is the second most common infection after respiratory tract infections in the community. In hospitals, UTI accounts for approximately 35% of all hospital -acquired illnesses. Uropathogenic E. coli (UPEC) accounts for 70%. Increased rates of MDR isolates of E. coli make it a difficult -to -treat pathogen. Materials & Methods: UPEC isolates confirmed by MALDI -TOF were included in the study. The isolates were tested for antibiotic sensitivity to different antimicrobials, and the production of Beta -lactamases viz. ESBL, MBL, and AmpC by phenotypic and genotypic assays. Their clonality was determined by the RAPD. Results: Out of 1150 urinary samples, 122 yielded pathogens, of which 55 were E. coli. Twenty -nine (52.7%) multi -drug resistant isolates were tested for beta -lactamases. All (29) isolates were positive for ESBL, and 6 isolates also harboured MBL genes by PCR. None of the isolates produced AmpC. OXA (n=21) was the commonest followed by TEM and SHV. Among the MBLs, SPM, GIM, IMP, and VIM were detected. Thirteen isolates had Multiple types of beta -lactamase genes. Conclusion: 53 per cent of our E. coli isolates were MDR. All of them produced beta -lactamases. Hence, routine ESBL testing for uropathogens would be useful for all cases of UTI.