HCV-RNA detection using different PCR methods in sera, cryoglobulins and peripheral blood mononuclear cells of patients with mixed cryoglobulinemia.

Objective. The hepatitis C virus (HCV) is frequently associated with mixed cryoglobulinemia (MC), and a number of authors have reported the presence of anti-HCV antibodies and HCV-RNA in the blood of MC patients. The presence of the HCV genome in the blood cells of individuals infected by HCV may correlate with the etiopathology of MC. We investigated the presence of HCV-related sequences in the sera, cryoglobulins and peripheral blood mononuclear cells (PBMC) of patients with MC and of individuals with type C chronic active hepatitis (CAH). Methods. 39 patients with MC, 11 non-cryoglobulinemic HCV-positive individuals with CAH, and 2 anti-HCVnegative controls were included in the study. The presence ofHCV-RNA was detected by nested RT-PCR and by a commercial kit. The PCR was performed by amplifying the 5'-non coding region (5'-NCR) of HCV. Results. HCV-RNA was detected in the sera and cryoglobulins ofabout 90% of the patients ; the commercial kit showed a higher sensitivity than nested PCR. One MC patient showed HCV-RNA only in the cryoglobulins. HCV-RNA was present in the PBMC of 14 of the 20(70%) MC patients analyzed. No differences in serum and PBMC HCV-RNA positivity were found between MC patients and controls. Conclusion. Our results confirm the spread of HCV infection among patients with MC. HCV-RNA is present in the serum, cryoglobulins and PBMC of large proportion of MC patients. The prevalence of HCV-RNA in the PBMC of MC patients and controls did not differ significantly ; this may suggest a tropism of HCV for PBMC regardless of the presence of cryoglobulinemia.