Leucocytoclastic vasculitis associated with mixed cryoglobulinaemia and hepatitis C virus infection.

Mixed cryoglobulinaemia is frequently associated with chronic hepatitis. We report a patient with mixed cryoglobulinaemia, hepatitis C virus (HCV) infection and palpable purpura. The skin manifestations were diagnosed as leucocytoclastic vasculitis in view of both the clinical appearance and the histological findings. In this study, we demonstrated the presence of IgG-class anti-HCV-antibody, HCV-RNA and IgA-class rheumatoid factor in the cryoprecipitate. These results suggest that the cryoglobulinaemia in this case was caused by aggregation of an immune complex comprised of HCV and anti-HCV antibody with IgA-type-rheumatoid factor, and that this led to a cutaneous vasculitis.