Extrahepatic immunological complications of hepatitis C virus infection.

Chronic hepatitis C virus (HCV) infection is frequently associated with a number of extrahepatic complications. In the majority of cases the underlying pathogenetic mechanisms are immune mediated, as evidenced by the presence of circulating autoantibodies (mixed cryoglobulinemia), whereas for others a localized host cellular immune response is implicated (e.g. sialadenitis, lichen planus). In this review, the latest data on the pathogenesis and clinical manifestations of the most common autoimmune extrahepatic manifestations of chronic HCV infection are presented.