Background: Uropathogenic Escherichia coli (UPEC) is one of the most important etiologic agent of urinary tract infection (UTI). UPEC strains have various types of virulence factors such as adhesins, toxins and iron uptake systems. Virulence genes are located on transmissible genetic elements and/or in particular locus on the chromosome called pathogenicity islands (PAI). The aim of this study was to investigate the prevalence of UPEC and the virulence factors among the UPEC isolates.

Materials and Methods: Of 370 urine samples collected from hospitalized patients with UTI in Kashan Shahid-Beheshti hospital, a total of 150 E.coli strains were isolated between December 2012 and June 2013. Biochemical and standard microbiological techniques were used to identify the E.coli followed by screening for virulence genes using the polymerase chain reaction (PCR).

Results: The prevalence of UTI infection was 40.5% and the frequency of UPEC virulence genes was traT (74%), aer (30.7%), PAI (61.4%), sfa (0%), pap ( 16.7%), cnf1 (0%), afa (0%) and hly ( 4.5 %).

Conclusion: Our study showed that the traT, PAI and aer virulence genes were highly prevalent among the UPEC strains isolated from hospitalized patients in our region therefore, these genes could be studied as targets for medical interventions.