High prevalence of hepatitis C virus RNA in the supernatant and the cryoprecipitate of patients with essential and secondary type II mixed cryoglobulinemia.

Detection of hepatitis C virus RNA by polymerase chain reaction was performed in 26 patients with type II mixed cryoglobulinemia, and compared with anti-HCV antibody detection. The patients were divided into two groups according to etiology: 15 had essential type II mixed cryoglobulinemia and 11 had secondary type II mixed cryoglobulinemia. In the essential type II mixed cryoglobulinemia group, the prevalence of hepatitis C virus RNA detected by polymerase chain reaction was 60% in the supernatant and 93% in the cryoprecipitate. In the secondary type II mixed cryoglobulinemia group the prevalence of hepatitis C virus RNA was 45% in the supernatant and 55% in the cryoprecipitate. The differences between the two groups were not statistically significant. In both patient groups, detection of hepatitis C virus RNA in the cryoprecipitate was the most sensitive test for hepatitis C virus infection. These results suggest that hepatitis C virus might be involved in the origin of mixed cryoglobulinemia.