Comparative Evaluation of the Prevalence of Extended Spectrum Beta-Lactamases (ESBLs) Producing E. coli in Fecal and Urine Samples of Women with Community Acquired UTIs

Introduction and Objectives: Uropathogenic E. coli (UPEC) which are the principal agent of urinary tract infections (UTIs) can originate from intestinal microbiota or from vaginal microbiota, contaminated foods and environments. The ability of commensal or uropathogenic E. coli to produce extended spectrum beta-lactamases (ESBLs) result in resistance to the beta-lactam antibiotics that are important drugs for treatment of UTIs. So, the aim of this study was to evaluate and compare the prevalence of ESBL-producing E. coli in fecal and urine samples of women with community acquired UTIs. Materials and Methods: During seven months, fecal and urine samples were collected from 30 non-hospitalized women with UTIs who referred to different hospitals of Kerman, Iran. The 60 samples were directly cultured on MacConkey agar and lactose‐fermenting colonies were confirmed as E. coli by conventional biochemical tests. Susceptibility of the 60 isolates to cefotaxime, ceftazidime, and ceftriaxone were analyzed by Kirby-Bauer method. To determine the ESBL activity, the isolates which were resistant to at least one of the tested antibiotics were submitted to phenotypic confirmatory test using cefotaxime disks with and without clavulanic acid according to CLSI guidelines. Results: Prevalence of resistance to cefotaxime was 10.0% vs. 28.5% in fecal and urinary E. coli isolates. These prevalence for ceftazidime and ceftriaxone were 13.3% vs. 21.4% and 10.0% vs. 14.2%, respectively. Totally, six (10%) E. coli isolates were confirmed as ESBL- producer. Rates of ESBLs-positive E. coli in fecal and urinary isolates were 3.3% and 17.8%, respectively. Conclusion: Comparative evaluation of the prevalence of antibiotic resistance and rate of ESBLs activity in fecal and urinary E. coli isolates revealed no significant difference (P > 0.05). The data warns increasing of resistance to beta-lactam antibiotics in E. coli which could limit the therapeutic options and increase the mortality rate of UTIs patients.

کلیدواژه ها:

Antibiotic resistance ، ESBLs ، UTIs ، Commensal and uropathogenic E. coli