Virulence genes and antibiotic susceptibility patterns of Escherichia coli isolated from nosocomial urinary tract infections in the northwest of Iran during 2022–2023: A cross‐sectional study

Background and Aims Urinary tract infections (UTIs) are prevalent among hospitalized patients, constituting the most frequent health‐care infections. Uropathogenic Escherichia coli (UPEC) is leading causative agent of UTIs. The present study was aimed to examine the susceptibility of UPEC isolates obtained from nosocomial cases to antibiotics, as well as their biofilm formation capability and frequency of virulence genes. Methods A total of 100 UPEC isolates were collected from nosocomial UTIs at Imam Reza Hospitals in Tabriz, Iran, spanning from April 2022 to January 2023. The antimicrobial susceptibility patterns were evaluated using the disk diffusion method, along with the detection of broad‐spectrum β‐lactam enzymes (ESBLs) and carbapenemases. The ability of isolates to form biofilms was assessed using the microtiter‐plate method, while the PCR method was employed to identify the presence of virulence genes. Results The highest resistance was observed toward piperacillin (82%), followed by aztreonam and ciprofloxacin (81%), while the lowest resistance was found against piperacillin/tazobactam (12%) and meropenem (9%). ESBLs were detected in 62% of the isolates. The microtiter‐plate results revealed strong, moderate, and weak biofilm formation abilities in 32%, 33%, and 24% of the isolates, respectively. The most prevalent virulence gene was fimA (74%) followed by hlyF (68%), papA (44%), papC (32%), iroN (26%), and cnf (20%). Conclusion The elevated levels of resistance to multiple antimicrobial agents, coupled with the co‐presence of virulence genes and biofilm formation abilities, contribute to the persistence of UPEC‐related infections, particularly in hospitalized patients. These findings underscore the necessity of implementing an effective program to control nosocomial UTIs caused by UPEC in the healthcare centers.