Excretion, deconjugation, and absorption of bile acids after colectomy for ulcerative colitis. Comparative studies in patients with conventional ileostomy and patients with Kock's reservoir.

Bile acid metabolism was studied in 26 patients with a continent ileostomy (Kock's reservoir) and 32 patients with conventional ileostomy. All had been colectomized for ulcerative colitis. In patients with a continent ileostomy the 14C-glycocholic acid breath test showed increased pulmonary 14CO2 excretion as evidence of abnormal bacterial deconjugation of bile acids and increased faecal 14C excretion as evidence of bile acid malabsorption. Faecal bile acid excretion, determined chemically, and, by inference, bile acid synthesis were only moderately increased (median, 1.8 mmol/day). The disturbance of bile acid metabolism was similar to that found in 32 patients with conventional ileostomy, but more pronounced with higher faecal 14C. A significant difference was that no abnormal bacterial deconjugation took place in patients with conventional ileostomy, since their pulmonary 14CO2 excretion was subnormal. Stool mass was almost identical in the two groups, with median values of 665 and 663 g/day, respectively. Faecal fat excretion was normal in most in both groups. Thus bile acid metabolism is slightly more disturbed in patients with a continent ileostomy than in patients with conventional ileostomy. The resulting malabsorption was modest in both groups.