Colitis, Collagenous

**Definition:** A subtype of MICROSCOPIC COLITIS, characterized by chronic watery DIARRHEA of unknown origin, a normal COLONOSCOPY but abnormal histopathology on BIOPSY. Microscopic examination of biopsy samples taken from the COLON show larger-than-normal band of subepithelial COLLAGEN.

**Tree numbers:** - C06.405.205.265.173.500 - C06.405.469.158.188.173.500

**Synonyms:** - Collagenous Colitis