Identification of Virulence Genes and Antibiotic Resistance Patterns of Escherichia coli in Samples from Patients Referred to Medical Centers of Mazandaran University of Medical Sciences in 2022

Authors
Mahdieh Mousivand
Elnaz Akbari Alaei
Mohammadreza Khosravi Largani
Sara Ghandi
Hamidreza Goli
Mehrdad Gholami
10.61186/ibj.25th-11th-IACRTIMSS
Abstract
Introduction: Urinary tract infections (UTIs), commonly caused by Escherichia coli, are widespread. The virulence factors of E. coli enhance its ability to adhere, establish infection, and resist antimicrobial resistance. This study aimed to investigate the presence of virulence genes and antibiotic resistance patterns in E. coli strains obtained from patients at hospitals affiliated with Mazandaran University of Medical Sciences.

Methods and Materials: In this descriptive cross-sectional study, we collected and analyzed 100 positive clinical specimens (urine cultures) containing E. coli obtained from patients with UTIs. We assessed the antimicrobial susceptibility profile of the E. coli isolates using the Kirby-Bauer disk diffusion method on Mueller-Hinton agar media, following the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Additionally, we employed PCR with specific primers to identify three virulence genes: papC, fimH, and afa. Statistical data were analyzed using SPSS version 16 software and descriptive statistical tests.

Results: Among 100 patients diagnosed with UTI, 82 isolates were found in females (82%) and 18 isolates in males (18%). The highest incidence of UTIs was observed in the youngest age group (0-25 years) at 42%, followed by the age groups 25-50 years (22%) and 50-75 years (21%). The lowest incidence was recorded in the oldest age group (75-95 years) at 15%. All samples demonstrated sensitivity to tobramycin and amikacin antibiotics. Subsequently, imipenem, cefoxetine, and gentamicin exhibited the highest sensitivity against E. coli, with the rates of 99%, 98.80%, and 94.60%, respectively. The prevalence of fimH, papC, and afa genes in E. coli isolates was 73%, 39%, and 8%, respectively. Additionally, ampicillin displayed the lowest sensitivity among all antibiotics tested.

Conclusion and Discussion: The current study revealed that among patient isolates, the fimH, papC, and afa virulence genes were the most prevalent. Moreover, women exhibited a higher frequency of virulence factors compared to men. All samples demonstrated sensitivity to tobramycin and amikacin antibiotics while displaying the highest resistance to ampicillin.



Keywords
Escherichia coli
Urinary tract infections
Virulence Factors