Abstract
A 71-year-old female suffered from long term watery diarrhea after taking an anticoagulant (cilostazol). Colonoscopic findings showed edematous mucosa, indistinct vascular transparency and granular appearance. Colonoc mucosal biopsy showed marked thickening of the subepithelial collagen band and a number of lympho-plasma cells in the lamina propria. A case of collagenous colitis caused by cilostazol has not been reported in Japan and a magnifying endoscopy with indigo carmine spraying was very useful in diagnosing this disease, which is worth reporting.
