Prevalence of Pathogenicity Islands and Fim H Virulence Genes in Escherichia coli Strains Isolated from Urinary Tract Infection in Rasht City, Iran

Uropathogenic Escherichia coli (UPEC) is one of the most important etiologic agents of urinary tract infection (UTI). The UPEC strains have various types of virulence factors, including adhesions, toxins, and iron uptake systems. Virulence genes are located on transmissible genetic elements and/or on particular locus on the chromosome called pathogenicity islands (PAI). The aim of the current research was to evaluate the frequency of PAI and Fim H virulence genes among E. coli strains isolated from UTIs in Rasht, Iran.

This study was conducted on 50 E. coli strains, which were isolated from patients with UTIs referring to several medical laboratories of Rasht city. E. coli was identified using standard microbiological techniques and biochemical assays. Furthermore, the prevalence of PAI and Fim H virulence genes were evaluated using the polymerase chain reaction (PCR) technique.

The results showed that 76% of the females and 24% of the males were infected with UTI (P<0.01), which was indicative of the higher rate of UTIs in females than in males. Based on the results of PCR, 42 (84%) and 38 (76%) isolates were positive for Fim H and PAI genes, respectively. Additionally, 33 (66%) isolates carried both of these genes.

As the findings indicated, the prevalence of PAI and Fim H virulence genes in E. coli strains accounted for a high rate of UTI. Therefore, these genes could be studied as targets for medical interventions and epidemiological studies