Diarrhoea was a common problem in the kwashiorkor seen in Kampala, contributing to the mortality and delay in recovery. Enteric infection was found in only a few children (8%), but when present it caused particularly severe diarrhoea and was frequently complicated by septicaemia.Sugar intolerance often occurred to lactose and other sugars, both monosaccharide and disaccharide. The children were most commonly intolerant of lactose, and some of these may have had a hereditary lactase deficiency.Antibiotics are rarely indicated for the treatment of diarrhoea in kwashiorkor in Kampala. If reducing substances are found in the stool of a child on a milk diet, a diet based on sucrose is substituted, and if intolerance persists a fructose diet is given. A few children are intolerant of all sugars, including fructose, and for these the prognosis is grave.