Immunological alterations in hepatitis C virus infection.

A higher prevalence of immunological processes has recently been reported in patients with hepatitis C virus (HCV) infection, focusing the attention of physicians and researchers on the close association between HCV and immune disorders. HCV lymphotropism represents the most important step in the pathogenesis of virus-related immunological diseases and experimental, virologic, and clinical evidence has demonstrated a trigger role for HCV both in systemic autoimmune diseases, such as rheumatoid arthritis, Sjögren syndrome, hemolytic anemia and severe thrombocytopenia, and in organ-specific autoimmune diseases, such as autoimmune hepatitis, thyroid disorders and diabetes. This review will outline the principal aspects of such HCV-induced immunological alterations, focusing on the prevalence of these less characterized HCV extrahepatic manifestations.