Cryoglobulins - immunoglobulins that precipitate in vitro at temperatures < 37°C and redissolve after rewarming. • Cryoglobulinemia - refers to the presence of cryoglobulins in serum. • Cryoglobulinemic disease or cryoglobulinemic vasculitis - used to describe patients with symptoms related to the presence of cryoglobulins