Prevalence of bla oxa-1 and bla shv Genes in E. coli Isolates from Hospitalized Patients in Rasht

Background and objective: extended-spectrum beta-lactamases (esbl) are widely produced by escherichia coli strains. the aim of this study was to determine frequency of blaoxa-1 and blashv genes in e.coli strains isolated from patients hospitalized in city of rasht, iran. methods: in this cross-sectional study, 200 samples were collected from patients. the e. coli strains were identified using morphological characteristics and biochemical tests. antimicrobial susceptibility testing was performed. the prevalence of the bla oxa-1 and blashv genes in the e. coli isolated was assessed by pcr method. results: overall, 160 e. coli strains were isolated. of these, 83 (51.9%) showed esbl activity while 71 (48.1%) did not. all positive strains were resistant to cephalothin. moreover, 98.8% of esbl-producing strains were resistance to amoxicillin, cefotaxime and ceftriaxone. the prevalence of the blaoxa-1 and blashv genes in esbl-producing strains were 45% and 17%, respectively. in addition, 28.9% of the strains had both genes while the genes were absent in 9.6% of the strains. conclusion: prevalence of the blaoxa-1gene is higher than that of the blashv gene. the absence of both genes in some isolates indicates the possible role of other genes in the esbl activity.