Differences in the presence of nine urovirulence factors among clinical isolates of Escherichia coli causing
cystitis and
pyelonephritis in women and
prostatitis in men have been studied.
Hemolysin and necrotizing factor type 1 occur significantly more frequently among isolates causing
prostatitis than among those causing
cystitis (P < 0.0001) or
pyelonephritis (P < 0.005). Moreover, the papGIII gene occurred more frequently in E. coli isolates associated with
prostatitis (27%) than in those associated with
pyelonephritis (9%) (P < 0.05). Genes encoding
aerobactin and PapC occurred significantly less frequently in isolates causing
cystitis than in those causing
prostatitis (P < 0.01 and P < 0.0001, respectively) and
pyelonephritis (P < 0.01 and P < 0.0001, respectively). No differences in the presence of Sat or type 1 fimbriae were found. Finally, AAFII and
Bfp fimbriae are no longer considered uropathogenic
virulence factors since they were not found in any of the strains analyzed. Overall, the results showed that clinical isolates producing
prostatitis need greater virulence than isolates producing
pyelonephritis in women or, in particular,
cystitis in women (P < 0.05). Overall, the results suggest that clinical isolates producing
prostatitis are more virulent that those producing
pyelonephritis or
cystitis in women.