This 50-year-old woman presented with painful necrotic lesions on her left cheek and left ear. She also had livedo reticularis on both lower legs and early gangrene with blistering of both feet. Her carotid and pedal pulses were strong.
Laboratory findings at admission included a normocytic anemia with unremarkable leukocyte and platelet counts, rouleaux formation on the peripheral blood film, 3+ proteinuria, and an elevated serum creatinine level.
Because this patient had strong carotid and pedal pulses, the necrosis of her cheek and ear together with early gangrene of her feet indicated microvascular occlusions. And since her initial laboratory findings suggested multiple myeloma, the possibility of associated cryoglobulinemia immediately came to mind. Subsequent studies confirmed both diagnoses.
Cryoglobulins are proteins—most commonly immunoglobulins—that precipitate, crystallize, or gel when cooled but redissolve when warmed. They are classified as follows: Type I, a monoclonal protein occurring most often in multiple myeloma but also in B-cell neoplasms; Type II, a mixture of monoclonal and polyclonal proteins; and Type III, consisting solely of polyclonal proteins.