Cold agglutinin autoimmune hemolytic anemia in nonhematologic malignancies

Four patients with nonhematologic malignancies had the simultaneous finding of hemolytic anemia due to high-titer cold agglutinins. In each patient, the cold agglutinin had "anti-I" specificity and was of the IgM kappa immunoglobulin class. Although patients with hematologic malignancies not uncommonly have cold agglutinins, the association between these antibodies and nonhematologic malignancies is unusual.