Diarrhoea after continent ileostomy.

To determine the nature and frequency of malabsorption in patients with continent ileostomies, faeces and urine from 42 patients with ileal pouches and from 19 patients with conventional ileostomies were analysed and compared. The patients with conventional ileostomy were matched with patients with ileal pouches. Thirteen of the patients with pouches were found to have excessive faecal volumes which were accompanied by increased faecal losses of electrolytes, nitrogen, and fat, and by decreased vitamin B12 uptake. The remaining patients with continent ileostomies had faecal and urinary outputs which were similar to those of patients with conventional ileostomies. Thus, evidence of malabsorption was found in approximately 30% of this group of patients with continent ileostomies.