Cryoglobulins

Cryoglobulins are abnormal proteins (antibodies) in the blood that clump together and become solid or gel-like in cold temperatures, then dissolve again when rewarmed. When present, they can inflame and block blood vessels, leading to a condition called cryoglobulinemia—which may cause symptoms such as skin rashes, joint pain, weakness, and damage to the nerves or kidneys. It is often linked to infections (especially hepatitis C), autoimmune diseases, or certain blood cancers.