Permeability of Erythrocytes

OF SPECIAL INTEREST XANTHINURIA AND HEMOCHROMATOSIS. J. H. Ayvazian. From Veterans Administration Hospital, N. Y. New England J. Med. 270: 18-22, 1964. A 47-year-old white male with hemochromatosis manifested by hepatomegaly, diabetes, greatly elevated serum iron, completely saturated iron binding capacity and hemosiderinuria, but only a trace of marrow hemosiderin, had a serum uric acid of less than 1 mg./100 ml. Urinary xanthine and hypoxanthine excretion were 40-80 times normal. Liver xanthine oxidase was less than 10 per cent of normal. Xanthine oxidase deficiency may be the common metabolic error because this enzyme is required both for the oxidation of hypoxanthine and xanthine to uric acid, and the simultaneous reduction of ferric ferritin to ferrous ferritin, the latter a step necessary before the transport of iron from the liver.-R. 0. W.