ABSENCE OF HISTOPATHOLOGICAL CHANGES OF ILEUM AND COLON IN FUNCTIONALCHRONIC DIARRHEA ASSOCIATED WITH BILE-ACID MALABSORPTION, ASSESSED BYSEHCAT TEST - A PROSPECTIVE-STUDY

Objectives: Chronic diarrhea of unknown origin is often associated wit h bile acid malabsorption, the pathogenetic role of which is uncertain . The aim of this study was to identify morphological abnormalities in the ileal and colonic mucosa in patients with this disorder. Methods: We performed a prospective and blinded histopathological study (betwe en June 1991 and November 1992) of endoscopic biopsies of the distal i leum and colon of 23 patients suffering from chronic diarrhea of unkno wn origin. In 14, the SeHCAT (75-selena-homo-cholic acid taurine) test was abnormal owing to bile acid malabsorption; in the other nine, the diarrhea control group, the test results were normal. A detailed eval uation of surface epithelium, immune response and inflammatory changes was made. Results: in two patients and two controls, mild villous atr ophy was observed; there was also slight inflammation of the ileal and colonic mucosa occurring with the same frequency in both groups. A sl ight replacement of goblet cells was more evident in the diarrhea cont rol group. Conclusions: Chronic diarrhea of unknown origin associated with bile acid malabsorption does not involve specific morphological c hanges of ileal or colonic mucosa, and its pathogenesis must be looked for in dysfunction of the ileum and/or colon.