Endocrine manifestations of HCV-positive cryoglobulinemia

Abstract

Hepatitis C virus (HCV) is known to be responsible for both hepatic and extrahepatic diseases. Among systemic HCV-related extrahepatic diseases (HCV-EHDs), mixed cryoglobulinemia (MC) has been extensively studied. More recently, an increased prevalence of endocrine disorders has been observed in a large series of HCV-infected patients with MC. The most frequent and clinically important endocrine disorders in MC are thyroid disorders and type 2 diabetes mellitus (T2D). A significant association between MC and thyroid autoimmunity and hypothyroidism has been shown. A high prevalence of thyroid cancer has also been reported. Furthermore, several clinical epidemiologic studies demonstrated that MC is associated to T2D. An increasing number of studies have linked a Th1 immune response with HCV infection, MC, autoimmune thyroid disorders, and diabetes. These data suggest a common immunological Th1 pattern as the pathophysiological basis of the association.