Abstract
Jejunal biopsies from 20 well nourished children (average age 12.8 mo.) with gastroenteritis and 20 children (average age 20 mo.) with protein-energy malnutrition were examined by immunofluorescent technique for IgA, G, M, E and D, and for epithelial glycoprotein secretory component. Compared with previous studies on normal infants, the children with gastroenteritis showed a moderate increase in IgA-containing cells, a large increase in IgM-containing cells and no change in IgG-containing cells. These findings are similar to previously recorded findings on adults with gastroenteritis. There was a pronounced and highly significant decrease in IgA-containing cells in the jejunal mucosa of the children with protein-energy malnutrition. No significant differences were noted between the populations of IgG-, IgM-, IgE- and IgD-containing cells in the 2 groups. This selective deficiency in mucosal IgA probably results from a delay in maturation of the secretory IgA system; the mechanisms of such a deficiency are discussed.