Immunochemical and ultrastructural investigations in a patient with cold-agglutinine-active monoclonal IgMK-gammopathy.

A patient with "chronic cold-agglutinin disease" is described. Initially, the process was a benign monoclonal gammopathy. After an intervall of 6 years clinical, cytomorphological and immunochemical studies showed progress towards malignancy. In the bone marrow intranuclear lipid-like inclusions appeared in the plasma cells.