Adherence Patterns and Invasion of Uropathogenic Escherichia coli Carrying fimH Gene

The present study aims to investigate two of the Uropathogenic Escherichia coli (UPEC) pathogenesis mechanisms, as adherence and invasion in primate kidney epithelial (Vero) cells. Methods: 20 E. coli isolates from outpatients with UTI in one public clinic were evaluated for adherence and invasive abilities in Vero cells. Results: All 18 positive isolates for fimH gene adhered to the Vero cells (100%). The two UPEC isolates that did not carry the fimH gene did not adhere. Two different UPEC adherence patterns were observed: aggregative adherence pattern (AA) and a pattern called “no typical adherence pattern” (NTA). Among 18 adherent UPEC isolates, 11 presented AA adherence pattern (61%) and 7 showed NTA pattern (39%). The high rate of adherence of the UPEC fimH positive isolates (≅90%) to Vero cells suggests the expression and participation of the FimH adhesin in UPEC adherence behavior. Invasive capacity of UPEC isolates ranged of about 6.5% to 15.33%. Results corroborate the fact that UPEC can persist in the urinary tract through its adhesion, as well as invade cells establishing the bacterial UTI process.