Cryoglobulinemia is defined as the persistent presence in serum of abnormal immunoglobulins (Igs) that precipitate at low temperatures and dissolve again upon warming. Cryoglobulins may be composed only of a monoclonal Ig (simple type I cryoglobulinemia), of a monoclonal Ig bound to the constant domain of polyclonal Ig heavy chains (mixed type II cryoglobulinemia), or only of polyclonal Igs (mixed type III cryoglobulinemia). The manifestations of type I cryoglobulinemia are often related to intravascular obstruction, whereas those seen in the mixed cryoglobulinemias often originate in true immune complex-mediated vasculitis. The main clinical manifestations affect the skin (purpura, necrotic ulcers), joints, peripheral nervous system, and kidneys (membranoproliferative glomerulonephritis). Patients with type I cryoglobulinemia should be investigated for hematological malignancies (myeloma and B-cell lymphoma). Hepatitis C is the main diagnosis to consider in patients with mixed cryoglobulinemia, followed by connective tissue disease and B-cell non-Hodgkin's lymphoma. The treatment depends mainly on the cause of the cryoglobulinemia. For instance, hepatitis C virus (HCV) eradication is in order in patients with HCV-associated cryoglobulinemia vasculitis, and the underlying hematological malignancy must be treated in patients with type I cryoglobulinemia.
Keywords: Cryoglobulin; Hematological disease; Hepatitis C; Vasculitis.
Copyright © 2019. Published by Elsevier Masson SAS.