Fulminant hepatitis and lymphocyte sensitization due to propylthiouracil.

Fulminant hepatic failure developed in a 24-year-old black woman who had been treated with propylthiouracil and propranolol for hyperthyroidism. Clinical and biochemical recovery followed discontinuation of drug therapy. Liver biopsy disclosed submassive hepatic necrosis. During the acute phase of the disease, lymphocyte transformation studies revealed sensitization of the patient's lymphocytes to propylthiouracil but not to propranolol. Sensitization remained demonstrable 2 months after cessation of the former drug. Lymphocytes obtained from a hyperthyroid patient treated with propylthiouracil without complications failed to show evidence of sensitization. These observations indicate that submassive hepatic necrosis may result from treatment with propylthiouracil and are consistent with the notion that sensitization mechanisms may be responsible for the hepatic injury induced by this drug.