Cryoglobulinemia: The presence in blood of abnormal proteins called cryoglobulins that, by definition, have the unusual properties of precipitating from the blood serum when it is chilled and redissolving upon rewarming. (Cryoglobulins are gamma globulins with a molecular weight of approximately 200,000.)

Cryoglobulins can cause problems by causing:

A condition called essential mixed cryoglobulinemia (EMC) involves cryoglobulin proteins which are a mixture of various antibody types that form for unknown (essential) reasons. EMC is characterized by joint pains and swelling (arthritis), enlargement of the spleen, skin vasculitis with purplish patches, and nerve, kidney and heart disease. Treatment is with medications which reduce inflammation and suppress the immune system. Plasmapheresis, in which the blood's serum is replaced with saline (salt water solution), may be done in severe cases.

Cryoglobulinemia can also accompany another disease such as multiple myeloma, dermatomyositis, or lymphoma.

Sometimes, small amounts of cryoglobulins are discovered by accident in the lab in a serum sample from someone with no apparent symptoms.