Phylogenetic Classification of Escherichia coli Isolated from Urinary Tract Infections in the Central Regions of Guilan Province

Introduction: Urinary tract infection (UTI) is one of the most common infectious diseases, and Escherichia coli is known as the most dominant causative agent of this infection in 90-80% of patients. There is not much information about the phylogenetic groups, types, and virulence factors of E. coli, causing UTIs from Iran. The objective of this study was to evaluate the antimicrobial susceptibility of E. coli strains isolated from patients with UTI and to determine the phylogenetic classification of the strains. Methods: In this cross-sectional study, 100 E. coli isolates were collected from patients with UTI from five laboratories in Rasht city. The isolates were confirmed by using morphological and biochemical common tests. The frequency of virulence genes and patterns of phylogenetic groups were performed using Multiplex PCR. Additionally, antimicrobial susceptibility of all isolates was evaluated by disk diffusion method. Results: Distribution of phylogenetic B2, D, A and B1 groups in the isolates were 64%, 24%, 12%, and 0%, respectively. The highest antibiotic resistance was reported to cefotaxime (84%), piperacillin, and cefixime (80%), and the lowest resistance was demonstrated to imipenem (8%), chloramphenicol and gentamicin (12%). Conclusion: Our findings showed that the B2 was the most prevalent phylogenetic group and the most resistant strain to generally used antibiotics among patients with UTI.