the relationship of class i integron gene cassettes and the multidrug-resistance in extended -spectrum β-lactamase producing isolates of escherichia coli

Background: integron is an important element in creating multi-drug resistant (mdr) bacteria. this study evaluated the relationship of class i integron and antibiotic resistance in extended-spectrum beta-lactamase producing (esbl) isolates of escherichia coli (e. coli).methods: a total of 66 esbl-producing e. coli were isolated from urinary tract infection in kermanshah and their antimicrobial susceptibility was assessed. the incidence of class i integron was determined in isolates using pcr. the class i integron-associated gene cassettes were also verified by dna sequencing. data were analyzed using statistical methods.results: of 66 esbl-producing isolates, 65 (98.5%) were mdr. the most prevalent antibiotic resistance of the isolates was observed for ampicillin (98.4%), ceftriaxone (98.4%), cefotaxime (95.4%), and co-trimoxazole (86.3%). the frequency of class i integron in isolates was 92.3%. the relationship between class i integron and resistance to streptomycin, co-trimoxazole, and ceftazidime was statistically significant. the genes encoding resistance to streptomycin and co-trimoxazole, as well as a gene encoding a protein with unknown function, were associated with class i integron. the most common gene cassette was dfra17-aada5.conclusions: the results indicate a high prevalence of antibiotic resistance among esbl-producing isolates to the antibiotics commonly used for the empirical treatment of urinary tract infections. the frequency of class i integron and associated gene cassettes involving resistance to antibiotics is high. there is a high percentage of mdr among the esbl-producing isolates, which mostly contain gene cassettes. these findings suggest a strong association of integron and esbl genes in the isolates.