Changes in erythrocyte superoxide dismutase in a patient with copper deficiency

In a patient with typical copper deficiency, we found superoxide dismutase (SOD, 1.15.1.1) activity and copper in erythrocytes to be decreased to 52% and 46% of age-matched controls, respectively. However, these were not so markedly depleted as plasma copper (17%) or ceruloplasmin (20%). After copper replacement therapy, erythrocyte copper and SOD activity gradually returned to the control levels. Although certain abnormalities reported in copper deficiency in animals were expected, osmotic fragility of the liver and heart were not a feature as far as could be determined by electrocardiography and routine laboratory examinations. Probably a decrease of SOD to this extent is not severe enough to lead to superoxide-induced damage.