Nosocomial E. Coli Isolated from UTI Identified Using DNA Markers Based on PCR and Pathogenic Markers

Background: Urinary tract infections (UTIs) are among the most common bacterial infections, with Escherichia coli (E. coli) being the leading causative agent. The increasing resistance of E. coli to commonly used antibiotics, including β-lactam antibiotics, poses a significant clinical challenge. Understanding antimicrobial resistance patterns and genetic diversity among E. coli isolates is essential for effective treatment and infection control. This study aimed to determine the prevalence of E. coli in UTI cases, assess its resistance to multiple antibiotics, evaluate β-lactamase and extended-spectrum beta-lactamase (ESBL) production, and analyze genetic diversity using molecular techniques. Materials and Methods: A total of 105 urine samples were collected from UTI patients at Rezali Hospital and General Hospital in Erbil (January–June 2024). Disk diffusion was used for antibiotic susceptibility testing, while MIC values were determined for penicillin and cephalosporin. β-lactamase production was assessed using the iodine titration method, ESBLs were confirmed using a disk proximity test, and RAPD markers were used for genetic diversity. Results: E. coli accounted for 48.51% of UTIs, showing high resistance to tetracycline (75.71%) and ceftriaxone (95.14%), and complete resistance to ampicillin and amoxicillin. β-lactamase production was detected in 84.62% of isolates, while 5.77% were ESBL producers. Genetic analysis indicated strain diversity, suggesting multiple nosocomial sources. Conclusion: The study highlights multidrug-resistant E. coli in UTIs, emphasizing the need for continuous surveillance and antibiotic stewardship programs to prevent treatment failures.