Increased Gardnerella vaginalis urogenital biofilm in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a systemic inflammatory condition that affects the entire organism, not only the bowel. An impaired interaction with microbiota has been shown to be important. We looked for bacterial factors, which may contribute to the well-known higher incidence of poor reproductive outcome in IBD.

Urine specimen of patients with Crohn's disease (N=42), ulcerative colitis (N=46), and randomly selected patients attending the General Internal Medicine Outpatient Clinic of the Charité for non-IBD related medical conditions (N=49) was analyzed for bacteria adherent to desquamated epithelial cells and diffusely distributed bacteria in the urine using fluorescence in situ hybridization.

The urine of IBD patients contained significantly more often Gardnerella vaginalis biofilms (CD 38%, UC 43%) than those of the control group (16%). There was no link between current disease activity, history of and present fistula and G. vaginalis biofilms, but the samples of patients with steroid refractory/dependent disease were significantly more often G. vaginalis biofilm positive. No significant differences in number of epithelial cells and leukocytes, and total bacterial counts were present.

There is a significant link between IBD and G. vaginalis biofilm. This observation suggests an epithelial barrier dysfunction of the genital tract. Since G. vaginalis is believed to be one of the reasons responsible for bacterial vaginosis, it may be an important factor in the well-known higher incidence of poor reproductive outcome in IBD. Excessive G. vaginalis biofilms in steroid refractory/dependent disease suggests a need to avoid long-term steroid therapy.