Extended spectrum beta lactamase producing E.coli isolated from Gorgan, North of Iran

Background and objectives: The increase of ESBL producing E.coli cancreate a tremendous difficult y for the health system. These isolates leads torapid transmission of causative genes to other clinically important bacteriaand synchronously increased resistant to other antibiotics. This study wascarried out to determine the prevalence of this isolate and related genes inGorgan, North of Iran.Material and Methods: This study was conducted on 218 isolated E.colifrom urinary tract infection of outpatients referring to six medical laboratoriesin Gorgan, during 2010-11. The resistance to Cefotaxim (Mast Co.) wasassessed by Kirby-Bauer disk diffusion method. The confirmatory test fordetection of resistant isolates was carried out by double disk method at thepresence of Cefotaxim and clavulanic acid. The presence of β lactamase geneof blatem, blactx and blashv in ESBL was assessed by PCR method.Results: of 218, 70 isolates (32.1%) are resistant to Cefotaxim. Sixty-two(88.6%) of them are confirmed as ESBL producing E.coli. β lactamase genesof blactx, blatem and blashv can be seen in 28(45.2%), 26(41.9%) and6(9.7%) isolates, respectively.Conclusion: the prevalence of ESBL producing E.coli in Gorgan is in therange of country average and blaCTX-M gene is the most common gene.Key words: E.coli, ESBL, bla gene, UTI