Primate model of sprue-like syndrome.

An experimental model resembling so-called tropical sprue has been produced in young, growing rhesus monkeys kept on a protein-deficient diet. At a 2% level of protein intake, the animals became frankly diseased after two months, but at a 5% protein intake the symptoms appeared after five months. The animals lost weight, their skin became brittle, the fur lost luster, and facial edema appeared. The hematocrit, and serum folate, protein and albumin were significantly decreased, and intestinal absorption of fat, D-xylose, radioactive vitamin B12 and folic acid showed marked depression. The jejunal mucosa showed moderate villous atrophy. Histochemical and electron microscopy changes were consistent with those seen in the human tropical sprue syndrome. It appears, therefore, that protein malnutrition plays an important role in the experimental tropical-sprue-like syndrome in monkeys.