Structural and functional abnormalities of the small intestine due to nutritional folic acid deficiency in infancy.

Structural abnormalities and disaccharidase deficiency were demonstrated in biopsies of duodenal mucosa from four infants who had symptoms of failure to thrive and chronic diarrhea associated with a megaloblastic anemia. Goat's milk was the main dietary constituent for each infant for six to eight months prior to presentation. The structural abnormalities consisted of villous blunting, crypt hypertrophy, megaloblastic changes in epithelial cells, and nuclear enlargement. All changes reverted to normal with the addition of folic acid to the diet. This study provides evidence that nutritional folic acid deficiency can cause structural and functional alterations of the small intestine in infants.