Diagnosis and therapy of collagenous colitis

Collagenous colitis is a chronic watery diarrhea disorder characterized by a subepithelial collagen layer. The disease mainly affects middle-aged wome n. The increasing number of publications indicates the growing interest on this entity. The diagnosis predominantly depends on biopsies from the macro scopically normal mucosa. The pronounced involvement of the proximal colon underlines the necessity of a total colonoscopy. Immunhistochemistry shows collagen type III. The etiology and pathogenesis of collagenous colitis is less well understood. Recently published studies suggest a decreased collag en desintegration rather than an accelerated collagen synthesis. However, no standard treatment has been introduced by controlled clinical t rials Symptomatic therapy with antidiarrhoica (e. g. loperamide, cholestyra mine) or antiinflammatory drugs (e. g. aminosalicylates, systemically actin g steroids) has been recommended. Moreover, the successful use a of the top ically acting steroid budesonide indicates a good clinical:response and a s mall number of side effects.