Graves' Hyperthyroidism Following Transient Thyrotoxicosis during Interferon Therapy for Chronic Hepatitis Type C

We report a case of Graves' hyperthyroidism induced by long-term interferon (IFN) therapy.A 52-year-old woman suffered from chronic active hepatitis type C and was treated with a total of 456×106 units of IFN-α for 23 weeks. During the 12th week of treatment she showed transient thyrotoxicosis. One week after the termination of IFN therapy, TSH-receptor antibodies became positive and subsequently she showed Graves' hyperthyroidism. This case showed sequential manifestation from transient thyrotoxicosis to the appearance of TSH-receptor autoantibodies, and then the occurrence of Graves' hyperthyroidism during IFN therapy. The course of this case may be useful in the understanding of the pathogenesis of autoimmune hyperthyroidism. (Internal Medicine 34: 58-60, 1995)