Effects of selenium supplementation on blood and urine selenium levels and liver function in patients with primary biliary cirrhosis.

To study the mechanism of the reduced serum selenium concentration in patients with liver damage we administered 200 micrograms (2.53 mumol) selenium daily as selenium-rich yeast to 8 patients with primary biliary cirrhosis and 8 healthy controls over 16 weeks. Initially selenium concentrations in serum were 24% lower (P less than 0.001) in patients than controls. During supplementation serum selenium levels increased in both groups but the difference between them persisted. Throughout the study whole blood selenium levels and glutathione peroxidase activities were also somewhat lower (P = NS) in patients than controls. Selenium supplementation had no effect on whole blood glutathione peroxidase activities in either group. The basal 24 h urinary excretion of selenium was similar in both groups but was increased more by supplementation in patients than controls. Selenium administration did not influence the liver function of the patients. We conclude that impaired hepatic production of selenium-containing serum compounds is the most likely explanation for the reduced serum selenium concentration in patients with primary biliary cirrhosis.