Background:Uropathogenic Escherichia coli (UPEC) with its virulence factors is the most prevalent cause of urinary tract infection (UTI).Objectives;This study aimed to determine the occurrence of fim, pap, sfa, and afa genes among 100 UPEC isolates collected from patients diagnosed with UTI.Materials and MethodsA total of 100 UPEC isolates were obtained from urine samples of patients with UTI. The prevalence of 5 virulence genes encoding type 1 fimbriae (fimH), pili associated with pyelonephritis (pap), S and F1C fimbriae (sfa and foc) and afimbrial adhesins (afa) were determined through PCR method. We also investigated the phylogenetic background of all isolates. In addition, the distribution of adhesin-encoding operons between the phylogroups was assessed.Results:The prevalence of genes encoding for fimbrial adhesive systems was 95% for fim, 57% for pap, 16% for foc, and 81% for sfa. The operons encoding for afa afimbrial adhesins were identified in 12% of isolates. The various combinations of detected genes were designated as virulence patterns. The fim gene, which occurred in strains from all phylogenetic groups (A, B1, B2, and D) was evaluated and no significant differences were found among these groups. Conversely, significant differences were observed in relation to pap, afa, foc, and sfa operons.Conclusions:These results indicate that the PCR method is a powerful genotypic assay for the detection of adhesin-encoding operons. Thus, this assay can be recommended for clinical use to detect virulent urinary E. coli strains, as well as epidemiological studies.

Background: Escherichia coli is one of the most causative pathogen of urinary tract infection. Urinary tract infections (UTIs) are the second most common cause of morbidity and remain a serious health concern among the clinicians. The severity of UTI caused by uropathogenic E. coli (UPEC) is due to the expression of a wide spectrum of virulent factors such as adhesin coding operons. Little is known about the relationship between the E. coli genetic background and the acquisition of adhesin coding operons in UPEC isolates. Objectives: The aim of this study was to determine the prevalence of adhesin coding operons in UPEC isolates belonged to phylogenetic group B2 and A collected from patients suffering from UTI. Materials and Methods: A total 100 UPEC isolates were used for DNA extraction by the boiling lysis. The analysis of phylogenetic groups, along with detection of adhesin coding operons was performed by Multiplex-PCR method. Associations were assessed between afa, fim, foc, pap and sfa operons among to 55 B2 and 17 A groups E. coli isolates. Statistical analysis was performed using Fisher exact test. Results: Phylogenetic analysis showed that 55 and 17 of 100 UPEC isolates belonged to the B2 and A phylogenetic groups, respectively. The afa, fim, foc, pap and sfa operons were present in five (9.09%), 55 (100%), 16 (29.09%), 46 (83.63%) and 46 (83.63%) of UPEC isolates belonged to phylogenetic group B2, and two (12.50%), 14 (87.50%), one (6.25%), two (12.5%) and 12 (75%) of isolates belonged to phylogenetic group A, respectively. Statistical analysis showed that pap gene was significantly more frequently detected in phylogenetic group B2 (P < 0.05). Conclusions:The UPEC isolates belonging to group B2 harbored a greater number of adhesin coding operons than strains from phylogenetic groups A.