The cell population of the upper jejunal mucosa in tropical sprue and postinfective malabsorption.

The cell population of the upper jejunal mucosa has been studied in cases of tropical sprue from the Far East and Middle East, and in similar cases arising in western Europe (;post-infective malabsorption'), and compared with cases of untreated coeliac disease and patients without small bowel disease.Infiltration of the epithelial layer of the upper jejunal mucosa by lymphocytes was found in tropical sprue to the same extent as in coeliac disease, and, to a lesser extent, in ;postinfective malabsorption'.In the lamina propria, in all forms of acute sprue there was an increased density of lymphocytes. With increasing duration and with increasing mucosal atrophy, the lymphocytes were progressively replaced by plasma cells, and the cellular infiltration in chronic sprue was indistinguishable from that of coeliac disease.The findings suggest that a humoral antibody response is a feature of sprue, and becomes more prominent as the condition becomes chronic.