Absence of hyperparathyroidism in severe liver disease

Elevated serum levels of intact parathyroid hormone (PTH) have been reported in severe versus mild biliary cirrhosis. The aim of this study was to determine whether hyperparathyroidism was present in severe liver disease on the basis of the inability of the liver to catabolize the hormone. Because biologic activity resides in the amino terminal, and amino terminal PTH determinations have not been routinely made in liver disease, it is possible that hyperparathyroidism was previously missed in these patients. Accordingly, we obtained fasting blood from 11 patients with severe liver disease and 8 age-matched controls. We measured intact, amino terminal, and mid-region PTH, vitamin D metabolites, bone gamma carboxyglutamic acid protein (BGP), ionized calcium, phosphorus, magnesium, and liver function tests. Serum levels of PTH were normal with all assays and 1,25(OH)₂D levels were not elevated. These findings argue against the possibility that hyperparathyroidism plays a role in the pathogenesis of hepatic osteodystrophy.