COMPARATIVE ANALYSIS OF VIRULENCE CHARACTERISTICS OF DIARRHEIOGENIC Escherichia coli IN E. coli STRAINS ISOLATED FROM PATIENTS WITH DIFFERENT TYPES OF URINARY INFECTION

Abstract

Some adapted clones of Escherichia coli carry genes that encode properties that allow them to colonize different host sites, favoring the establishment of intestinal or extraintestinal infections. Intestinal infections are caused by different diarrheogenic E. coli (DEC) pathotypes, while the extraintestinal infections are caused by strains of extraintestinal pathogenic E. coli (ExPEC). ExPEC strains isolated from urinary tract infection (UTI) (cystitis and/or pyelonephritis) are also called uropathogenic E. coli (UPEC). Recent reports have shown that certain virulence genes, located on Pathogenicity Islands or plasmids, can be transferred from DEC strains to ExPEC or vice versa, leading to the formation of hybrid strains, which have the potential to cause more severe extraintestinal infections or even intestinal infections. However, we are unaware of studies that evaluated the potential of colonization of the hybrid UPECs and determined their genotypic and phenotypic diversity. In this study, the occurrence of hybrid UPEC strains will be evaluated in patients with cystitis, pyelonephritis and asymptomatic urinary infections. Hybrid and non-hybrid strains will be compared for serotypes, phylogenetic and clonal groups, presence of plasmids, biofilm production and adherence capacity in vitro. As part of UTIs occurs due to colonization of the urethra by strains from the feces, hybrid UPEC strains will also be screened in the feces of the patients studied and evaluated for a potential relationship with occurrence of diarrhea. A comparative analysis of the genome of selected hybrid strains will also be performed. The knowledge generated in this study will contribute to the elucidation of the pathogenesis of hybrid UPECs in UTIs and their potential specificity regarding colonization sites and the capacity to generate intestinal infections in the same host, contributing to a more adequate management of these diseases of extreme global relevance. (AU)