ACQUIRED LACTOSE MALABSORPTION IN THAI CHILDREN

One hundred seventy-two normal Thai infants and children were studied to determine the prevalence of lactose malabsorption and lactase deficiency. These abnormalities became manifest after infancy, and by age 2 years virtually all children studied were abnormal. Sucrase and maltase activities and sucrose and glucose absorption were normal in most. Calculation of ratios of median maltase/lactase, sucrase/lactase, and maltase/sucrase activities also indicated the major abnormality to be isolated lactase deficiency. Lactose malabsorption appeared earlier in life in a group of normal institution Thai children compared to a group of village children. This suggests that environmental factors may be important in the pathogenesis of lactase deficiency in Thai children, although genetic influences cannot be excluded.