Absorption Studies after Ileal J-Pouch Anastomosis for Ulcerative Colitis: A Prospective Study

Abstract

Absorption studies were performed in 17 patients with ulcerative colitis operated on with colectomy and an ileal two-limbed J-pouch anastomosis. The patients were studied 3 and s≥18 months after closure of the temporary ileostomy. Increased stool mass (median, 609g/24h) was found in all patients and was unchanged with time. Moderate steatorrhoea was present in 29% of the patients 3 months postoperatively, but faecal fat excretion normalized with time. Calcium absorption was normal in all but one patient regardless of time after operation. An abnormal bacterial deconju-gation, evaluated by a ¹⁴C-glycocholic acid breath test was present in 27% of the patients and increased significantly with time. Forty per cent of the patients had increased faecal bile acid excretion. B₁₂ malabsorption was present in 29–35% of the patients. In conclusion, ileal J-pouch anastomosis for ulcerative colitis causes increased stool mass in all patients and produces moderate bile acid deconjugation and malabsorption in about one-third to half. Substitution therapy with vitamin B₁₂ is necessary in about one-third of the patients. Intestinal adaptation as far as absorption is concerned is minimal after the first 3 postoperative months.

Key Words:

• Bile acid metabolism
• calcium absorption
• faecal fat
• ileal J-pouch anastomosis
• stool mass
• ulcerative colitis
• vitamin B₁₂ absorption