Cryocrystalglobulinemia.

A 40-year-old woman had cryocrystalglobulinemia with IgG2(K1). To date, 27 other cases of spontaneous crystallization of a plasma protein have been reported. In all, the protein, a cryoglobulin, has been found to be an IgG molecule. The disease most commonly associated with this phenomenon has been multiple myeloma. None of the patients have had Raynaud's phenomenon, but many have had purpuric skin lesions made worse by exposure to cold. In the two cases of essential cryocrystalglobulinemia, crystals were found in the peripheral blood film. Immunologic, biochemical and ultrastructural studies have so far not demonstrated any property common to all cryocrystalglobulins.