Selenium metabolism and supplementation in patients with Duchenne muscular dystrophy was studied at the Muscle Research Center, Department of Medicine, University of Liverpool, and the Universitat Klinik Mainz, Mainz, FRG. Plasma selenium concentrations measured in seven Duchenne muscular dystrophy patients and in 11 age matched normal boys showed no significant difference after two months of sodium selenite supplementation (1 mg selenium daily). All patients demonstrated a rise in plasma selenium concentration as did all but one of the normal subjects. The studies did not confirm any abnormality of selenium metabolism in patients with muscular dystrophies, and there was no evidence that high dose selenium supplementation influenced the activity of the selenium dependent enzyme glutathione peroxidase in skeletal muscle. An elevation of thiobarbituric acid-reacting substances in the muscle of patients with Duchenne muscular dystrophy was unaffected by selenium supplementation. 
COMMENT. The present finding of normal plasma selenium concentrations in Duchenne muscular dystrophy patients differs from reports from Finland where selenium in soils and indigenous food stuffs is naturally low in concentration. The increase in thiobarbituric acid-reacting substances in dystrophic muscle confirms previous reports but the elevated levels in patients with Duchenne muscular dystrophy contrasted with normal levels in patients with other forms of muscular dystrophy and in control subjects.