PREVALENCE OF THE 4 GENES ENCODING FIMBRIAE IN UROPATHOGENIC ESCHERICHIA COLI CLINICAL ISOLATES AND STATISTICAL ANALYSIS OF RELATIONSHIP BETWEEN THE ABUNDANCE OF THIS VIRULENCE FACTORS AND PHYLOGENETIC GROUPS

Background and Aim:Escherichia coli is one of the microorganisms most frequently involved in urinary tract infections (UTIs); E. coli strains generally fall into one of four phylogenetic groups A, B1, B2, and D and that virulent extra strains belong mainly to group B2 and, to a lesser extent, to group D. Uropathogenic E.coli (UPEC) show different virulence factors too.Methods:138 UPECs clinical isolates were investigated , In addition 30 E.coli as a control were collected from feces of healthy humans. On the one hand multiplex PCR assays were performed for investigating 4 genes encoding fimbriae and on the other hand PCR assays were performed for investigating Phylogenetic Groups distribution. finally statistical analysis was used to compare the occurrence of virulence markers in cases and controls. Results were considered as statistically significant at P < 0.05.Results:From 138 (UPEC), 1(12%), 76(55%), 29 (21%) and 17 (12%) strains were related to B1, B2, D and A phylogenetic groups respectively and 86 (62.3%), 20 (14.4%), 1 (0.7%) and 17 (12.3%) isolates presented fimH, sfa/focDE, focG and sfaS genes respectively. Prevalence of the fimH gene in isolates were statistically more than those belonging to Flora groups (P≤0. 001).Conclusion:Although in some studies, more virulence were observed in the B2 phylogenetic group and indicating that most isolates of virulence factors belong to the group B2 But in the current study, fimH as a virulence factor was found to be statistically significant correlated to phylogenetic groups and these factors (p < 0.05)

کلیدواژه ها:

Escherichia coli ، phylogenetic groups ، virulence factors