Faecal diversion for Crohn's colitis: a model to study the role of the faecal stream in the inflammatory process.

The high incidence of clinical remission after faecal diversion for Crohn's colitis suggests the faecal stream may play a part in the inflammatory mechanism. The effect of faecal diversion (n = 22) and restoration of intestinal continuity (n = 10) was assessed in patients with Crohn's colitis and compared with controls. Faecal diversion produced significant improvement in the disease activity index mean (SEM) (before 176 (9); after 114 (9), p < 0.01) and serum albumin concentrations (before 33 (3.0); after 38 (3.0), p < 0.05) in all patients with Crohn's colitis. The crypt cell production rate (CCPR) was maintained after faecal diversion for Crohn's colitis but fell in the control group (before = 3.6 (0.8)), at two (1.4 (0.4), p < 0.02), and six weeks (1.6 (0.4), p < 0.05). Mucosal glucosamine synthetase activity, reflecting glycoprotein synthesis, was significantly lower in patients with Crohn's colitis (analysis of variance p < 0.05) after diversion but was maintained in the control group. Restoration of intestinal continuity failed to produce reciprocal changes. The sustained cellular proliferation and fall in glycoprotein synthesis in Crohn's colitis after faecal diversion may represent the end of an exaggerated protective response and regenerative hyperplasia after exclusion of the faecal stream. This study suggests the faecal stream may participate in the inflammatory process in Crohn's colitis. The underlying mechanism is unknown.