How I treat cryoglobulinemia.

Cryoglobulinemia is a distinct entity characterized by the presence of cryoglobulins in the serum. Cryoglobulins differ in their composition, which has an impact on the clinical presentation and the underlying disease that triggers cryoglobulin formation. Cryoglobulinemia is categorized into two main subgroups: type I, which is seen exclusively in clonal hematologic diseases, and type II/III, which is called mixed cryoglobulinemia and is seen in hepatitis C virus infection and systemic diseases such as B-cell lineage hematologic malignancies and connective tissue disorders. Clinical presentation is broad and varies between types but includes arthralgia, purpura, skin ulcers, glomerulonephritis, and peripheral neuropathy. Life-threatening manifestations can develop in a small proportion of patients. A full evaluation for the underlying cause is required, because each type requires a different kind of treatment, which should be tailored on the basis of disease severity, underlying disease, and prior therapies. Relapses can be frequent and can result in significant morbidity and cumulative organ impairment. We explore the spectrum of this heterogeneous disease by discussing the disease characteristics of 5 different patients.