Immune Hemolytic Anemia Associated with Biclonal Cold Autoagglutinins

A 65-year-old man with bladder outlet obstruction due to prostatic hypertrophy was incidentally discovered to have cold-antibody autoimmune hemolytic anemia (cold-aggluthinin syndrome; CAS) due to autoanti-I (titer 1,024 at 4 degrees C and 64 at 30 degrees C), and a biclonal gammopathy. Immunofixation electrophoresis of serum and a red blood cell eluate revealed the patient's autoantibody to be biclonal IgM kappa and IgA kappa. No underlying cause could be determined to explain the development of either the biclonal gammopathy or the CAS. To our knowledge, this is the first reported case of CAS associated with a biclonal gammopathy and biclonal cold autoagglutinins of the IgM kappa, IgA kappa type.