Cold agglutinin syndrome: What are the symptoms?

Cold agglutinins are abnormal proteins in your blood. These proteins act as antibodies, causing your red blood cells to clump together and die prematurely — especially when your body is exposed to temperatures colder than normal body temperature. Most healthy people have a small number of cold agglutinins. Cold agglutinin syndrome occurs when you have high numbers of cold agglutinins. This can lead to a form of destructive (hemolytic) anemia, in which red blood cells are destroyed faster than bone marrow can replace them.

Signs and symptoms of cold agglutinin syndrome include:

• Color changes in the skin on your nose, ears, lips, hands and feet in response to cold (Raynaud's phenomenon)
• Painful fingers and toes with cold exposure
• Death of tissue due to insufficient blood supply to that tissue (ischemic necrosis)

The cause of cold agglutinin syndrome is unknown. A doctor can confirm a diagnosis of cold agglutinin syndrome by blood tests. Treatment may include:

• Avoiding extremely cold temperatures
• Chemotherapy