GENETIC PROFILE OF UROPATHOGENIC Escherichia coli: PATHOGENICITY ISLANDS MARKERS, VIRULENCE FACTORS AND PHYLOGENETIC CLASSIFICATION

Urinary tract infection (UTI) is considered one of the most common bacterial infections and Escherichia coli is the most frequently isolated pathogen in these infections. E. coli strains isolated from urine are members of the group of extraintestinal pathogenic E. coli (ExPEC), denominated uropathogenic E. coli (UPEC). UPEC strains usually present factors that generate their permanence and multiplication in the bladder. Virulence factors are predictors of pathogenicity and include adhesins, toxins, siderophores, capsules and invasins, which facilitate host colonization and invasion, defense mechanism evasion, tissue injury and / or stimulation of the host's inflammatory response. The objective of the study was to investigate the presence of virulence factors, islands of pathogenicity markers (PAI) and determine the phylogenetic classification of 44 ESBL producing UPEC of inpatients from University Hospital of Londrina-PR. The isolates were previously identified by the Vitek© 2 system and stored at -4oC until the moment of the study. The research was performed using the polymerase chain reaction (PCR) method with specific primers for each gene. The most prevalent gene was fyuA (54.5%), followed by iutA (45.5%), traT (40.9%), kpsMT II (34.1%), kpsMT K5 (20.5%), hlyF (13.6%), papC (13.6%), ompT (13.6%), iroN (11.4%), cva (11.4%), ibeA (11.4%), cnf1, (4%), hlyA (9.1%), iss (9.1%), afa (6.8%), kpsMT K1 (4.5%). No papG, sfaA, sfaS and cnf2 genes were detected in UPEC isolates. The most prevalent PAI markers was PAI IV 536 (54.5%), followed by PAI I CFT073 (36.4%), PAI II CFT073, (27.3%) PAI II J96 (11.4%), PAI I 536 11.4%), PAI II 536 (9.1%). No PAI I J96 marker was detected. The most common phylogenetic group was B2 (27.3%), followed by B1 (18.2%), A (15.9%), E (15.9%), F (11.4%), C (2.3%), and 4 isolates were not grouped. UPEC strains generally have several virulence factors that allow them to resist and overcome the innate immune response of the host. Such genes are often encoded within PAIs and are acquired by the bacterium by horizontal transfer of genes by plasmid, bacteriophage or conjugal transposon. The expression of several genetic markers of virulence enables UPEC to cause infection of the urinary tract. Phylogenetic group and virulence genes research are tools to improve knowledge about the E. coli population and the association with the disease.