Introduction: E. coli is the predominant causes of urinary tract infection. Several virulence factors for bacterial infections in the urinary tract are required. In this study, we have considered several virulence factors in strains isolated from the patients with UTI in Yazd.
Methods: In this cross-sectional study in 2015-2016, 146 strains isolated were collected from the patients with urinary tract infection. After confirmation by phenotypic and genotype methods, frequency of gene fimH, pap C, aer was evaluated using specific primers by PCR method. The pattern of antibiotic resistance of isolates was determined by disk diffusion method.
Results: In the present study, the prevalence of virulence genes was fimH (87%), aer (85.6%) and papC (9.6%). Among 146 E. coli isolates, resistance rate for various antibiotics were as follows: 57.2% to Cotrimoxazole, 54.8% to Nalidixic acid, 45.9% to Cefazolin, 40.4% to Cefixime, 42.5% to Cefalotin, 41.8% to Cefalexin, 31.5% to Norfloxacin, 30.1% to Ofloxacin, 28.3% to Ciprofloxacin, 24% to Gentamicin, 19.9% to Amikacin, 1.4% to Nitrofurantoin, and 1.4% to  phosphomycin. The results showed that the most and less frequent resistant was seen in Cotrimoxazole and Nitrofurantoin, phosphomycin, respectively.
Conclusion: In this study, the frequency of fimH gene was higher than other genes. In addition, according to the pattern of antibiotic resistance nitrofurantoin and phosphomycin are suitable medicines for the treatment of patients in our region.