[Extrahepatic manifestations of hepatitis C infection].

The hepatitis C virus is associated with various extrahepatic manifestations. It is unequivocal that hepatitis C is associated with mixed cryoglobulinemia, membranoproliferative glomerulonephritis, and in Southern Europe to some extend also with porphyria cutanea tarda. The rare combination of hepatitis C and panarteriitis nodosa is still questionable. The Sicca syndrome also seems to be associated with hepatitis C virus, but this is not the typical Sjögren syndrome. It is still unclear whether the rare combination of hepatitis C with aplastic enemia has pathogenetic aspects. Although an epidemiological association of hepatitis C with lichen planus, lymphoma, neuropathies and other diseases has been observed, the etiological role and the pathogenetic involvement of the hepatitis C infection remains unclear. Furthermore, the question whether these extrahepatic diseases observed are autoimmune diseases remains open. Concerning the practical approach in a clinical setting, it has to be pointed out that with these diseases a hepatitis C infection has to be considered and testing for hepatitis C antibodies and, if positive, hepatitis C-RNA is indicated. If there will be any evidence of an etiological association of a replicative hepatitis C infection and the mentioned extrahepatic diseases antiviral medication should be discussed.