Cold agglutinin disease
Cold agglutinin disease is a form of a cold autoimmune haemolytic anaemia. The cold autoimmune haemolytic anaemia is a form of autoimmune haemolytic anaemia involving cold-reacting antibodies. It is caused by cold-reacting autoantibodies, usually IgM. The hemolysis of the red blood cells occurs mostly at cold temperatures, typically 28-31 °C. Cold agglutinin disease and paroxysmal cold hemoglobinuria are examples of cold autoimmune haemolytic anaemia. The common antibody involved is the IgM antibody directed against the I/i antigens on red blood cells.
In cold agglutinin disease, there is a high concentration of IgM antibodies that are directed against red blood cells. These antibodies bind to red blood cells particularly at low body temperatures, especially during winter.
There are two forms of cold agglutinin disease: primary and secondary. The primary cold agglutinin disease is idiopathic, i.e. the disease or condition arises spontaneously or for which the cause is unknown. The secondary cold agglutinin disease is associated with another disease. In adults, conditions such as lymphoma and chronic lymphoid leukemia result in cold agglutinin disease. In children, Mycoplasma pneumonia infection and mononucleosis have been found to cause cold agglutinin disease.