MIXED CRYOGLOBULINEMIA IN PATIENTS WITH H EPATITIS-C VIRUS-INFECTION

Mixed cryoglobulinemia occurs in about half of all patients with chron ic hepatitis C, Mixed cryoglobulinemia results from a lymphoproliferat ive disorder caused by polyclonal. lymphocyte B proliferation (type II I) or expansion of a B-cell clone producing monoclonal Ig with anti-im munoglobulin activity (type II), Among the different viral infections studied to date (hepatitis A or B, cytomegalovirus, Epstein-Parr or he rpes simplex virus) none except hepatitis C has been formally linked t o cryoglobulinemia. The mechanisms involved with the hepatitic C virus and persistant cryoglobulinemia are unknown, Several studies have sho wn that the hepatitis C virus plays a distinct role in the pathogenesi s of cryoglobulinemia. The high content of anti-HVC antibodies and vir al RNA in the cryoprecipitates suggests that entire viral particles or encapsidized viral RNA may be involved, Viral variability over time a nd within the same individual might be responsible for repeated antige nic stimulation of the immune system leading to proliferation or expan sion of the B-cell clone.