Anti-neutrophil antibodies in chronic hepatitis and the effect of alpha-interferon therapy.

In 34 patients with non-A non-B, 28 with type B and 11 with autoimmune chronic hepatitis, anti-neutrophil antibodies were investigated using indirect immunofluorescence and anti-myeloperoxidase antibodies by enzyme-linked immunosorbent assay. Granulocyte-specific antinuclear antibodies, were detected in 14 patients with advanced stages of non-A, non-B hepatitis (41%). Their presence correlated with histological features of disease activity but not with response to interferon therapy. Within 24 h after the first dose of interferon, 9 of these became negative and 3 more became negative after 1, 3 and 5 months. Myeloperoxidase-positive perinuclear neutrophil cytoplasmic antibodies were detected in a single patient and increased reaching a peak level after 8 weeks of interferon, decreasing thereafter. In type B, all were negative before and during the 6 months of therapy. In 6 patients with autoimmune hepatitis (55%), myeloperoxidase-negative perinuclear neutrophil cytoplasmic antibodies were detected in high titers. The association of granulocyte-specific anti-nuclear antibodies with non-A, non-B hepatitis support the hypothesis that hepatitis C virus infection might trigger humoral autoimmune response. In chronic autoimmune hepatitis, perinuclear neutrophil cytoplasmic antibodies appear as another marker of autoimmunity.