[Diagnosis in malabsorption syndromes--which tests are really necessary?].

The symptoms of the malabsorption syndrome are uniformly weight-loss, diarrhea and/or steatorrhea for which symptoms numerous etiological factors could be responsible: biliary and pancreatic diseases, inborn and acquired intestinal diseases, sequelae of operations (post-gastrectomy syndrome), metabolic and autoimmune diseases and several drugs. Accordingly, the spectrum diagnostic tools is rather broad and often confusing, comprising simple methods like measurement of faecal weight up to complicated radioactive or morphological techniques. In the present paper the available diagnostic procedures are grouped together and evaluated according to their importance, practicability and sensitivity in hospital and praxis. It turns out that simple laboratory techniques are sufficient for the majority of patients with malassimilation syndrome which have been specifically dealt with. However, in numerous cases a more detailed and specific diagnostic investigation is necessary in which single findings as a whole reflect the picture of the underlying disease. Only the knowledge of these rare investigational techniques will prompt the involved physician to transfer the patient with the unknown cause of malabsorption syndrome to a specialized medical centre.