Hepatitis C virus infection in type II essential mixed cryoglobulinemias
The possible relationship between essential mixed cryoglobulinemias (EMCs) and hepatitis C virus (HCV) has been investigated in eight patients with type II EMCs and biochemical signs of liver damage, whose serum tested positive in the ELISA for anti-HCV. Sera were tested using the 2nd generation RIBA assay, while serum HCV-RNA was measured semiquantitatively by a RT-PCR in whole serum, cryoprecipitates and supernatants. In all patients a percutaneous liver biopsy and a bone marrow biopsy were performed. At liver biopsy, chronic active hepatitis and/or cirrhosis were present in 6 patients; in the remaining two, a lymphoplasmacytoid infiltration of elements positive for kappa light chains was found. In all patients a bone marrow biopsy showed a paratrabecular infiltration of monoclonal lymphoplasmacytoid elements similar to those found in the liver of the two patients described above. Antibodies against structural and non-structural HCV proteins were detectable in the serum of all patients. HCV-RNA was amplified from the whole sera, cryoprecipitates and supernatants: significantly higher concentrations were found in cryoprecipitates than in supernatants. Our results confirm the high prevalence of HCV infection and ongoing viral replication in patients with type II EMC and suggest the possible implication of HCV in EMC pathogenesis.