Adherence of Escherichia coli to epithelial cells in the pathogenesis of urinary tract infection.

The role of bacterial adherence in the pathogenesis of recurrent urinary tract infection was investigated using an I125 E. coli-epithelial cell assay. In vitro bacterial adhesion to buccal, vaginal epithelial and uroepithelial cells of periurethral or rectal E. coli isolated from each subject was measured in 21 patients with recurrent urinary tract infection and 10 normal controls. Percent adherence of E. coli to buccal, vaginal, and uroepithelial cells was significantly (p less than .005) greater in patients with recurrent infection, compared with controls (32.9 +/- 4.0 vs. 14.1 +/- 7.3; 32.3 +/- 8.1 vs. 15.4 +/- 6.6; 34.7 +/- 5.6 vs. 17.1 +/- 4.2, mean +/- S.D., respectively). For both patients and controls, correlation in adherence between vaginal, uroepithelial, and buccal cells was observed. There were no differences in adherence between patients with or without periurethral colonization with E. coli, and adherence was not influenced by age. Patients receiving antimicrobial prophylaxis had a significantly (p less than .005) lower mean adherence to vaginal (26.7 +/- 3.7 vs. 35.1 +/- 4.1) and uroepithelial (30.4 +/- 2.8 vs. 34.6 +/- 3.2) cells, but not for buccal epithelial cells, compared with patients not receiving prophylaxis. These data support the hypothesis that increased receptivity of epithelial cells for bacteria plays a role in the increased frequency of vaginal colonization and subsequent infection in women who experience recurrent urinary tract infection.