[Cryoglobulinemic vasculitis]

Cryoglobulinemic vasculitis (CV) is a rare immune complex disease of small vessels (capillaries, venules or arterioles) with detection of cryoglobulins (CG). These are serum proteins that precipitate at temperatures below the normal body temperature. The laboratory diagnostics are logistically challenging because the temperature of the blood sample must be maintained continuously at 37 °C until arrival in the laboratory to prevent early precipitation of the proteins with adsorption to corpuscular blood components. Cryoglobulins can be divided into three classes (types I-III), with each class associated with specific underlying diseases and symptom complexes. Cryoglobulinemia can be caused by hematological, virological or autoimmune diseases and mixed forms also occur. The most common cause to date is a hepatitis C infection. Treatment of the underlying disease is obligatory, with antiviral treatment of hepatitis C offering the rare possibility of causal treatment. Depending on the severity of cryoglobulinemia, immunosuppressive therapy is indicated to prevent permanent damage caused by the inflammation.