Serotyping and Antibiotic Susceptibility Pattern of Common Bacterial Uropathogens in Urinary Tract Infections in Koohdasht, Lorestan Province

Background: One of the most common diseases worldwide is urinary tract infection (UTI). The main agents causing these infections are bacteria. Urinary tract infections occur when uropathogens colonize the urethra, migrate to the bladder and invade urinary tract cells. Objectives: The purpose of this study was the detection of uropathogens causing UTIs, as well as serotyping and antibiotic susceptibility of the most common bacteria. Materials and Methods: The study was performed on 300 urine samples collected from patients referred to Koohdasht Imam Khomeini hospital of Lorestan province. After culturing the samples and determination of uropathogens, antibiotic susceptibility test was performed by the Kirby-Bauer disk diffusion method. Serotyping was performed for the most common uropathogens by polyvalent and monovalent antisera. Results: Of the 300 samples, 61 samples (20.33%) were positive for UTIs. Among these, 49 samples (80.33%) were Gram-negative bacteria and 12 (19.67%) Gram-positive. The most common uropathogens in UTIs were Escherichia coli (55.74%), Proteus species (11.47%), Staphylococcus epidermidis (11.47%), Citrobacter species (8.20%), Staphylococcus aureus (8.20%) and Klebsiella species (4.92%), respectively. The rate of UTI in females (83.61%) was more than males (16.39%). The highest level of resistance was towards trimethoprim/sulfamethoxazole and the lowest to ampicillin, ciprofloxacin and nitrofurantoin. The most common uropathogen was Escherichia coli and the most common serotypes were O142:K86 and O25:K11, respectively. Conclusions: The treatment of UTIs and resistance control in bacteria should be done based on common strains and choosing an effective antibiotic. Therefore, the determination of prevalent bacterial strains in UTIs of each region based on laboratory tests is very important.