Prevalence of Some Adhesin Genes in E. coli Isolates from Patients with Community-Acquired UTIs

The most common form of extraintestinal Escherichia coli (E. coli) infection is urinary tract infection (UTI). The ability of E. coli to adhere to uroepithelium is an important feature in their pathogenicity and is required for colonization in urinary tract and establishment of the UTIs. Adhesion of uropathogenic E. coli (UPEC) to host receptors can mediate by fimbrial and afimbrial adhesins [1, 2]. Therefore, the aim of this study was to investigate the prevalence of papC (pili associated pyelonephritis; P fimbriae), csgA (curli fimbriae) and afa (afimbrial adhesin) genes among the E. coli isolated from patients suffering from community-acquired UTIs. This study was conducted on 78 E. coli isolates from urine of community-acquired UTIs patients which referred to the laboratory of Shahid Faghihi hospital in Shiraz, Iran. After confirmation of the E. coli isolates by standard microbiological methods, DNA of the isolates were extracted by boiling methods and the prevalence of papC, csgA and afa genes were investigated using PCR technique. The highest prevalence was detected for csgA gene (82.1%), followed by papC (44.9%), and afa (14.1%) genes. Approximately 7.7% of the 78 E. coli isolates harbored the all three adhesin genes, 42.3% harbored both csgA and papC genes, 12.8% harbored both csgA and afa genes, and 9% harbored both papC and afa genes. The majority of UPEC strains have different adhesion factors. The results of our study also showed the relatively high prevalence of adhesins among the UPEC isolates. These factors in addition to play role in adhesion to host’s uroepithelium, also roles in biofilm formations [3], which increase the resistance of the UPEC against antibiotic treatments and can act as bacterial reservoirs for recurrent infections. The study of molecular aspects of adherence in E. coli strains can help us to develop new vaccines and effective strategies for preventing UTIs mediated by E. coli.

کلیدواژه ها:

Adhesins ، E. coli ، Community-acquired UTIs ، PCR