Faecal mucus degrading glycosidases in ulcerative colitis and Crohn's disease.

Because the normal faecal flora includes bacteria which can produce mucus-digesting glycosidases, it follows that increased digestion of colonic mucus by these bacterial enzymes could be important in the pathogenesis of ulcerative colitis. Faecal activities of potential mucus-degrading glycosidases have therefore been assayed in samples from patients with inflammatory bowel disease and normal controls. The enzymes alpha-D-galactosidase, beta-D-galactosidase, beta-NAc-D-glucosaminidase alpha-L-fucosidase and neuraminidase were assayed. Considerable glycosidase activity was present in most faecal samples. Similar activities of all the enzymes assayed were found in faeces from patients with ulcerative colitis, Crohn's disease and normal controls and there was no significant correlation with disease activity. These results imply that relapse of ulcerative colitis is not initiated by increased degradation of colonic mucus by faecal glycosidases but do not exclude a role for bacterial mucus degradation in the pathogenesis of ulcerative colitis.