[Chronic diarrhea in malabsorption].

Chronic diarrhea with malassimilation is a symptom of numerous diseases ranging from celiac disease to lactate intolerance to chronic inflammatory bowel disease. Accordingly, they require an arsenal of diagnostic options. Clarification of the situation involves history-taking, a clinical examination, orientating and specific laboratory investigations, and imaging procedures, in particular ultrasound and endoscopy. Function tests such as the xylose-tolerance test, the H2 breath test or the various pancreas function tests are available as adjunctive options where indicated.