Cryopathic gangrene with an IgM lambda cryoprecipitating cold agglutinin.

Immunochemical and serologic studies of cold agglutinis in patients with chronic cold agglutinin disease (CCAD) have shown the almost exclusive occurrence of IgM kappa antibodies with specificity for the I antigen of red cells. An unusual subgroup of patients has been delineated in which the cryoprotein is IgM lambda, frequently lacks I specificity and often cryoprecipitates. Studies of such a protein from a patient with an unusual array of immunoproliferative disorders including Grave's disease with exophthalmos and Waldenstrom's macroglobulinemia indicate that the cryoprecipitating and cold agglutinating properties probably derive from the sam protein. The occurrence of this type of antibody should suggest the presence of a more aggressive lymphoproliferative disorder than simple CCAD.