Mixed cryoglobulinemia (MC) is a systemic disorder whose pathogenesis is based on the presence of serum cryoglobulins. The purpose of this study was to evaluate on a prospective basis patients presenting with MC with regard to the clinical manifestations and the underlying disorders. We present ten patients with MC, who were diagnosed and followed up during a one year period in the Division of autoimmune rheumatic diseases (Clinical Department of Pathophysiology). MC was associated with hepatitis C virus (HCV) infection in two cases, with hepatitis B virus (HBV) infection in six, one patient had both HCV and evidence of HBV infection, while the remaining three patients fulfilled European classification criteria for diagnosis of Sjogren's syndrome (SS). In all ten cases, the presence of an underlying factor was identified, being either vital or autoimmune. It is concluded therefore that all patients presenting with MC should be completely evaluated for a hepatitis virus infection or an autoimmune or lymphoproliferative disorder. Furthermore, since the initiation of the process of MC is triggered by many factors, research should be directed towards the identification of the underlying common denominator
