RESUMO
Thirty two children with chronic diarrhea of unknown etiology were prospectively investigated in a special hospitalization unit. They were all under 5 percentile for weight/height (NCHS). They had no edema and their age range was between three and eighteen months. The patients were given cow's milk and following the first jejunal biopsy they were fed one of three different diets as their only intake for a period of 15 days. The diets consisted of cow's milk and of two semi-elemental diets with different carbohydrate compositions. A second biopsy was taken at the conclusion of the specific diet. The jejunal biopsies were taken with a Crosby capsule just after the duodenal-jejunal junction and were analyzed by light microscopy. The morphological changes before and after 15 days of dietary treatment were evaluated. The children on semi-elemental diets showed a marked reduction of the number of interepithelial lymphocytes, and of lymphocytes in lamina propria. The infants on cow's milk showed no improvement. Our results suggest that cow's milk could be the cause of the persistent mucosal alterations observed in these infants.