OCCURRENCE AND SIGNIFICANCE OF AUTOANTIBO DIES IN THE COURSE OF INTERFERON TREATMENT OF CHRONIC HEPATITIS-C

Basic problem and objective: Autoimmunity may occur in chronic hepatit is C (CHC) as a primary event or may be induced by interferon-alpha (I FN-alpha). The existence of autoantibodies (AAB) is considered to be a contraindication to interferon treatment. It was the aim of this stud y to determine the extent to which signs of autoimmune disease occur i n the treatment of CHC with interferon, even in patients with existing antibodies. Patients and methods: In 1994 a pre-defined AAB spectrum and thyroid funtion parameters were determined every other month in 41 patients with CHC (16 women, 25 men; median age 42 years) before and after they had been treated with IFN-alpha, even when AABs were alread y present. Results: AABs were demonstrated in 17 patients (41 %) befor e and in 26 (63 %) during interferon treatment (P = 0.001). In 13 pati ents new AABs were demonstrated, while previously present AABs were no longer found in four patients. AABs against thyroglobulin (TGA) incre ased significantly, during interferon treatment (P = 0.001). All excep t thyroid AABs were demonstrable only at times and in low titres. None of the patients had an autoimmune disease before treatment. But autoi mmune thyroiditis developed in four of 19 patients with thyroid AABs. These patients also had constant TGAs in high titres, and antibodies a gainst microsomes were additionally demonstrated in two. No other auto immune disease occurred during or after interferon treatment. Conclusi on: Interferon frequently induces the formation of AABs. The demonstra tion of AABs before or during interferon treatment is no contraindicat ion to it, with the exception of preexisting thyroid antibodies, which indicate a high risk of autoimmune thyroiditis.