Hepatitis C virus-associated cryoglobulinemic vasculitis

A 74-year-old woman with a history of erythema presented with polyarthralgia and polymyalgia. Physical examination showed erythema affecting the shoulder (Figure 1A) and petechiae in the lower legs (Figure 1B). Laboratory examination revealed elevated levels of liver enzymes, including alanine aminotransferase (41 U/L) and aspartate aminotransferase (58 U/L). The RNA volume of hepatitis C virus (HCV) was positive (5.8 Log IU/mL), and its core genotype was 1b. Cryoglobulin was positive, and cryoglobulin immunofixation electrophoresis revealed mixed cryoglobulinemia consisting polyclonal IgG, IgA, and IgM.