Abstract
The most common causes of malassimilation are malabsorption and/or maldigestion. Clinical features always include weight loss and diarrhoea.
Symptoms are caused by abnormal intestinal luminal content and nutrient deficiency. At initial stage, the approach include history of disease, physical examination and initial laboratory investigation to prove malassimilation (undigested remnants of food in stool) and to distinguish between malabsorption and maldigestion (D-xylose test).