AUTOIMMUNITY AND THYROID-FUNCTION IN PATIENTS WITH CHRONIC ACTIVE HEPATITIS TREATED WITH RECOMBINANT INTERFERON ALPHA-2A

The occurrence of thyroid abnormalities and the appearance of organ- a nd non-organ-specific autoantibodies during long-term recombinant inte rferon alpha-2a (IFN-alpha) therapy were studies in 86 and 51 consecut ive outpatients with hepatitis C and B virus-related chronic active he patitis (CAH-HCV and CAH-HBV), respectively. Most patients had longsta nding community-acquired hepatitis. At baseline, 9.3% of CAH-HCV and 3 .9% of CAH-HBV patients showed clinical and/or biochemical signs of th yroid dysfunction. The remaining patients were euthyroid, although ant i-thyroid autoantibodies were found in 33/78 (42.3%) of CAH-HCV and in 5/49 (10.2%) of CAH-HBV patients. During IFN-alpha treatment, increas ed anti-thyroid autoantibody levels were seen in 40% of CAH-HCV initia lly negative patients, while they became detectable in no more than 10 % of CAH-HBV patients. Interferon-alpha-induced hypo- or hyperthyroidi sm was recorded in 12 of 35 CAH-HCV patients treated for 12 months (34 .3%). Only one CAH-HBV patient developed hyperthyroidism. High titers of anti-nuclear autoantibodies (ANA) were recorded at enrolment in 5/3 6 (13.8%) of CAH-HCV and in 3/16 (18.7%) of CAH-HBV patients. Only one CAH-HCV patient displayed anti-parietal cell antibodies (PCA). After IFN-alpha treatment, ANA were found in 10/28 (35.7%) and PCA in 2/28 ( 7.1%) of CAH-HCV patients, while an additional CAH-HBV patient develop ed PCA. but not ANA. However, no signs of systemic autoimmune disease were recorded. In conclusion. more than half of the patients with chro nic active hepatitis C, but only one-tenth of those with hepatitis B, displayed thyroid- and/or non-organ-specific autoantibodies prior to o r during treatment with IFN-alpha. As most of the antibody-positive pa tients developed permanent thyroid disorders during IFN-alpha therapy, the risk of development of organ-specific autoimmunity should be asse ssed carefully and incorporated in the cost/effectiveness analysis in patients with longstanding hepatitis who are candidates for IFN-alpha treatment.