A Case of Finger Necrosis Caused by Primary Macroglobulinemia with Cold Agglutinin Disease

Abstract

We herein report a case of finger necrosis caused by primary macroglobulinemia with cold agglutinin disease. A 65-year-old man was admitted to our hospital because of right index finger cyanosis and middle finger necrosis. The ischemic change extended from both fingertips to the distal interphalangeal joints. A cold agglutinin’s blood test was positive. A subsequent thorough examination revealed IgM kappa type M protein. Consequently, we diagnosed the patient with primary macroglobulinemia. Our case suggests that primary macroglobulinemia should be considered as a differential diagnosis for finger necrosis, although it may be of low priority.