The serum autoantibodies, antinuclear antibody, anti-DNA antibody, anti-smooth muscle antibody, antithyroglobulin antibody, antimicrosomal antibody, antimitochondrial antibody, rheumatoid factor and antibody to deoxyribonucleoprotein were measured at the baseline and on completion of interferon-α2a (IFN-α2a) treatment in chronic hepatitis C (CHC) patients who did not present with any autoimmune disease prior to treatment. Of the 57 patients examined, 27 spontaneously manifested at least one autoantibody. Only the prevalence of rheumatoid factor (26%) was significantly higher in the CHC patients than in the control subjects. There were no differences in the prevalence of the 8 autoantibodies examined between hepatitis C virus (HCV) genotypes, Ib and 2a/2b. Twenty-six patients responded to IFN-α2a. Subclinical hypothyroidism developed in two patients with elevated antithyroid antibody titers during treatment. No relationship was observed between changes in the status of autoantibodies and either response to IFN-α2a or HCV genotype. Irrespective of the HCV genotype, autoantibodies might be present in CHC patients before and during the IFN-α2a treatment. The presence of such antibodies does not represent a contraindication to the use of IFN-α2a in CHC patients not complicated by autoimmune diseases. Careful observations are necessary for CHC patients positive for antithyroid antibodies during the IFN-α2a treatment. Preexisting or newly developed autoantibodies do not necessarily predict a poor response to IFN-α2a.
(Internal Medicine 36: 248-254, 1997)