Lactose tolerance in normal Egyptian infants and children and in protein calorie malnutrition.

: Oral lactose tolerance test was performed on a total of 100 cases of normal Egyptian infants and children aged 6 months to 12 years. The same test was performed on 30 cases of protein calorie malnutrition (15 cases of marasmus and 15 cases of kwashiorkor). Detection of sugar and determination of pH were also carried out on all stools passed after the test. Lactose intolerance, as judged by a maximal blood glucose rise of 20 mg. or less and/or stools positive for sugar with a pH less than 6 following lactose ingestion, was observed as follows in normal cases: 12% in the age group 6 months to 2 years, 32% in the age group 2 to 5 years, 32% in the age group 5 to 9 years, and 80% in the age group 9 to 12 years. On the other hand, lactose intolerance was demonstrated in 73.3% of cases suffering from protein malnutrition. The aetiology and practical implications of the present findings of lactose intolerance on normal and malnourished children are discussed.