Evaluation of virulence factors and the adhesive capability of Escherichia coli strains.

Escherichia coli strains recently isolated from adult women with recurrent urinary tract infection (R-UTI) were compared with strains from women with non-recurrent infections (UTI). Haemolysin and mannose-resistant (MR) haemagglutinin were more prevalent in the first group. Using a spectrophotometric technique with biotinylated bacteria, the ability of bacteria to adhere to uroepithelial cells was related to this last character. R-UTI strains are also more resistant to the phagocytic activity of U937 cells. This could relate in vivo to a resistance to mucosal phagocytes, so as to prevent host defence mechanisms.