Extended spectrum B-lactamase mediated resistance in Escherichia coli in a tertiary care hospital.

Background: ESBL occur mostly in Enterobacteriaceae e.g. Escherichia coli. ESBLs are clinically important because they destroy cephalosporin's, work horse hospital antibiotics, given as first line agents to many severely ill patients. Delayed recognition and inappropriate treatment of severe infections caused by ESBL producers with cephalosporin has been associated with increased mortality. ESBL-mediated resistance is not always obvious in vitro to all cephalosporin. Many ESBL producers are multi -resistant to non-B-Lactam antibiotics such as quinolones and amino glycosides, narrowing treatment options. Some producers achieve outbreak status spreading among patients and locals, perhaps owing to particular pathogenicity traits.

Methods: A total of 221 Escherichia coli isolates from different clinical specimens during the period of August 2005 to July 2007, were screened for potential ESBL activity. These strains were isolated from different clinical specimens like urine, blood, sputum, pus and other body fluids which were received in the bacteriological division of microbiology.

Results: Two hundred and twenty one Escherichia coli isolates were isolated from different clinical specimens like urine, blood, sputum, pus and other body fluids submitted for both in and out-patients of the hospital during the period August2005 to July2007. All of them were subjected to screening by using ceftazidime, cefotaxime or ceftriaxone. Two hundred and eleven were positive for potential ESBL producers out of 221. 95.4%of E. coli (211/221) were screen positive which were subjected to confirmatory tests

Conclusion: Maximum number of ESBLs was from in-patients followed by out-patients. The out-patient presence of ESBL is of main concern as it is now come to the alert of the physician that ESBL is spreading fast in the community and responsible for community-acquired ESBLs and maximum number being from urine specimen.