Frequency of extended spectrum beta lactamase producing enterobacteriaceae among urinary pathogen isolates.

Abstract

To determine the frequency of extended-spectrum beta lactamase (ESBL) producing Enterobacteriaceae in urinary isolates. Observational study. Ziauddin University Hospital, Karachi, from February to October 2008. All members of Enterobacteriaceae isolated from urinary samples of in-patients were included and identified using standard biochemical tests. Urinary samples from out-patients were excluded. Detection of ESBL was carried out by double disk diffusion technique. Statistical analysis was performed by SPSS version 10. A total of 289 isolates of Enterobacteriaceae were identified during the study period. Of those 190/289 (65.7%) of the isolates were found to be ESBL producing. ESBL positivity within individual organism group was highest in Klebsiella species 84.16%, followed by Escherichia coli 68.55%, Enterobacter species 36.84%, and Proteus mirabilis 28.55%. Mean age of patients with ESBL producing organisms was 58.69 ± 18.97 years. ESBL production was almost similar in all age groups. A high frequency of ESBL producing organisms especially Klebsiella species and Escherichia coli amongst the hospital obtained urinary isolates was documented particularly in the older age group. The data points towards an urgent need for regular screening and surveillance for ESBL producing organisms in this region.