Introduction: Urinary tract infections (UTIs) are the most prevalent infections in patients worldwide. Escherichia coli is considered as the most prevalent etiological agent of UTIs. The prevalence of extended-spectrum beta-lactamase (ESBL)-producing isolates is a health care concern worldwide. The aims of this study was to determine antibiotic resistance profiles and the prevalence of the blaCTXM, blaSHV, and blaTEM genes in E. coli isolated from clinical samples obtained from patients with UTIs. Methods: From September 2019 to March 2021, a total of 1200 urine samples were collected and analyzed from patients suspected of having UTI referred to Amir-Al-Momenin hospital of Zabol, Sistan and Baluchistan province, south-east of Iran. Antibiotic resistance patterns and the prevalence of the blaCTXM, blaSHV and blaTEM genes were determined using the disk diffusion method and PCR, respectively. Results: The isolates were mostly resistance against ampicillin and trimethoprim-sulfamethoxazole, with 66% and 54% of all isolates being resistant. Also, the isolates investigated were highly susceptible against meropenem and gentamycin (95%). The prevalence of the blaCTX, blaSHV, and blaTEM genes was 22%, 30%, and 24%, respectively. Conclusion: Resistance against ampicillin and trimethoprim-sulfamethoxazole was high, therefore their prescription must be restricted. In addition, the expressions of the blaCTXM, blaSHV, and blaTEM genes were alarmingly high. In order to control the spread of infections by these isolates, constant monitoring of antibiotic resistance patterns is necessary.
Keywords: E. coli, Extended-spectrum beta-lactamase, Urinary tract infection, Antibiotic resistance