Presentation Type: Poster
Abstract: Background and Aim : Urinary tract infection (UTI) is a common bacterial infection and uropathogenic Escherichia coli (UPEC) strains are responsible for more than 80% of UTIs. UPEC strains with specific virulence factors, able to overcome the defenses of the host and cause disease. The purpose of this Cross-sectional study is evaluation of bacterial resistance to commonly used antibiotics and prevalence of some virulence genes among uropathogenic E. coli.
Methods : during 5 months (January 2014 to May 2015); a total of 150 UPEC strains were collected from midstream urine samples of patients with UTI referred to Imam Khomeini governmental Hospital in Boroujerd, Iran. The isolation and identification were performed by both biochemical and molecular methods. Antimicrobial susceptibility test was performed against ampicillin (10µg), ampicillin/sulbuctam (10/10µg), cefuroxime (30µg), cefazidime (30µg), cefotaxime (30µg), cefotaxime/clavulanic acid (30/10µg), nitrofurantoin (300µg), gentamycin (10µg), amikacin (30µg), nalidixic acid (30µg), ciprofloxacin (5µg), norfloxacin (10µg), trimethoprim/sulfametoxazol (25µg) for all isolates, according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Then prevalence of fimH, afaC, hlyCA and cnf-1 genes was examined for all isolates by PCR.
Results : The most antimicrobial resistance was against ampicillin= 127 (84.7%), nalidixic acid= 101 (67/3%) and trimethoprim/sulfametoxazol= 98 (65/3%) and the most effective antibiotics were nitrofurantoin and amikacin. Prevalence of fimH, afaC, hlyCA and cnf-1 genes was 80/7%, 4/7%, 16/7% and 16/7% respectively.
Conclusion : Our data shows a large prevalence of virulence factors genes, and antibiotic resistance in the UPEC strains isolated from patients. Due to the prevalence of UTI caused by E. coli and changing the antibiotic susceptibility patterns in Iran, Periodic studies in each province are needed. Better knowledge of the virulence and resistance characteristics of the infecting bacteria will guide physicians prescribing right antibiotics in cases where, there is no access to the results of urine culture. Antibiotic treatment without urine culture is not recommended yet. Despite being used for many years, we found that nitrofutantoin has the best clinical efficacy in UTI treatment.