BACKGROUND AND AIMS: In clinical practice, colonoscopy is widely used for the workup of chronic unexplained @entity294 . The aim of this study was to determine the yield of colonic biopsy in such an endeavor. METHODS: In a computerized database of 130   204 @entity1 evaluated for chronic @entity294 , we tested the influence of biopsy site, number of tissue fragments, @entity1 symptoms, and indication on the outcome of histopathologic evaluation. RESULTS: The population comprised 69% @entity1 and 31% @entity1 aged (mean  SD) 52.8  17.4 years. In 19% of @entity1 , histopathological analysis revealed various types of @entity3137 , the most common being @entity3178 (8.6%), @entity31 (2.2%), @entity30 (0.6%), active @entity1960 (5.0%), @entity4436 (0.1%), and @entity63 (0.5%). In 29% of @entity1 , the colonoscopy also revealed the presence of @entity1586 . Endoscopists tended to take significantly more tissue samples from endoscopically visible lesions than for random biopsies of macroscopically normal-appearing mucosa. CONCLUSION: Overall, these associations suggest that specific diagnoses lead to more biopsies, rather than more biopsies leading to more diagnoses. Colonoscopy is a successful tool in the workup of chronic @entity294 , yielding a definitive diagnosis in almost one-fifth of all @entity1 . As an added benefit, it also contributes to @entity5 prevention through the incidental findings of @entity694 .

The yield of colonic biopsy in the evaluation of chronic unexplained XXXX .

@entity1 :: ('9606', 'Species') :: ['women', 'patients', 'patient', 'men'] @entity63 :: ('MESH:D007511', 'Disease') :: ['colonic ischemia'] @entity5 :: ('MESH:D009369', 'Disease') :: ['cancer'] @entity294 :: ('MESH:D003967', 'Disease') :: ['diarrhea'] @entity31 :: ('MESH:D003093', 'Disease') :: ['ulcerative colitis'] @entity3178 :: ('MESH:D046728', 'Disease') :: ['microscopic colitis'] @entity1960 :: ('MESH:D003092', 'Disease') :: ['colitis'] @entity4436 :: ('MESH:D004238', 'Disease') :: ['diverticulitis'] @entity694 :: ('MESH:D003110', 'Disease') :: ['colonic neoplasm'] @entity30 :: ('MESH:D003424', 'Disease') :: ["Crohn's disease"] @entity3137 :: ('MESH:D009059', 'Disease') :: ['mucosal lesion'] @entity1586 :: ('MESH:D003111', 'Disease') :: ['colon polyps']
@entity294 :: (MESH:D003967,Disease) :: ['diarrhea']
