Essential mixed cryoglobulinemia without evidence for hepatitis B virus infection.

Prompted by reports associating essential mixed cryoglobulinemia with hepatitis B, we tested for hepatitis B markers in serum and cryoprecipitates and searched for virus particles by electron microscopy in cryoprecipitates from 12 patients with essential mixed cryoglobulinemia and 22 control subjects with mixed cryoglobulinemia secondary to recognized disease processes. None of the patients with essential cryoglobulinemia had detectable serum hepatitis B surface antigen (HBsAg) or antibody (anti-HBs), whereas five of the 22 patients with secondary cryoglobulinemia were positive for either HBsAg or anti-HBs. In cryoprecipitates from 10 patients with essential cryoglobulinemia, we could not detect HBsAg by radioimmunoassay or virus particles by electron microscopy, but one cryoprecipitate was anti-HBs-positive; however, four of 12 cryoprecipitates from patients with secondary cryoglobulinemia were positive for HBsAg or anti-HBs. Evidence of liver disease was present in similarly small proportions of both groups. Thus, in almost all our patients, essential mixed cryoglobulinemia was unrelated to hepatitis B infection.