Autoimmune hemolytic anemia (AIHA) is a rare but serious autoimmune disorder in which the body's immune system mistakenly attacks and destroys red blood cells. It is estimated that AIHA affects approximately one in every 50,000 people in the United States. The exact cause of AIHA is unknown, but it is believed to be the result of a combination of genetic and environmental factors. AIHA can be classified as primary or secondary, depending on the underlying cause.
Primary Autoimmune Hemolytic Anemia
Primary AIHA is caused by an abnormality of the immune system and is typically classified as either warm AIHA or cold AIHA. In warm AIHA, the body's immune system attacks red blood cells that have antibodies on their surfaces. In cold AIHA, the body's immune system attacks red blood cells that have antigens on their surfaces. Both types of AIHA result in the destruction of red blood cells and can lead to anemia, fatigue, jaundice, and other symptoms.
Secondary Autoimmune Hemolytic Anemia
Secondary AIHA is caused by an underlying medical condition, such as a bacterial or viral infection, a reaction to a medication, or a cancerous tumor. The underlying condition can trigger an immune system response that leads to the destruction of red blood cells.
Diagnosis and Treatment of Autoimmune Hemolytic Anemia
AIHA is typically diagnosed using a combination of blood tests, physical examination, and imaging tests. Treatment typically involves medications to suppress the immune system, as well as blood transfusions and other supportive therapies. In some cases, a splenectomy (surgical removal of the spleen) may be recommended.