Background: There are accumulating documentation of autoimmune mediated extrahepatic manifestations of hepatitis C virus infection. The virus is hepatotrophic and lymphotrophic. It mutates frequently with subsequent inadequate immune response and chronic stimulation of T and B cells. This may be one explanation for the increased frequency of the autoimmune diseases associated with hepatitis C virus infection.
Material and methods: In this review of the literature published in the period of 1990 to 2000, we present the most common extrahepatic manifestations of the hepatitis C virus infection.
Results: Mixed cryoglobulinaemia, membranoproliferative glomerulonephritis and membranous glomerulonephritis are highly associated with hepatitis C infection. Other autoimmune diseases may also be associated with hepatitis C infection, but further documentation is necessary.
Interpretation: Extrahepatic manifestations of hepatitis C virus infection are associated with several autoimmune diseases. When diagnosing an autoimmune disease, a test for a coinfection of hepatitis C is highly recommended. Antiviral therapy with interferon may in some cases reduce the activity of the autoimmune disease.