Autoimmune hemolytic anemia (AIHA) occurs when your immune system makes antibodies that attack your red blood cells. This causes a drop in the number of red blood cells, leading to hemolytic anemia. Symptoms may include unusual weakness and fatigue with tachycardia and breathing difficulties, jaundice, dark urine and/or splenomegaly. AIHA can be primary (idiopathic) or result from an underlying disease or medication. The condition may develop gradually or occur suddenly. There are two main types of autoimmune hemolytic anemia: warm antibody hemolytic anemia and cold antibody hemolytic anemia. Treatment may include corticosteroids such as prednisone, splenectomy, immunosuppressive drugs and/or blood transfusions.

In about half of cases, the cause of autoimmune hemolytic anemia cannot be determined (idiopathic or primary). This condition can also be caused by or occur with another disorder (secondary) or rarely, occur following the use of certain drugs (such as penicillin) or after a person has a blood and marrow stem cell transplant. Secondary causes of autoimmune hemolytic anemia include: 

• Autoimmune diseases, such as lupus
• Chronic lymphocytic leukemia
• Non-Hodgkin's lymphoma and other blood cancers
• Epstein-Barr virus
• Cytomegalovirus
• Mycoplasma pneumonia
• Hepatitis
• HIV

The outlook depends on the underlying cause of the disease and whether symptoms are managed appropriately and in a timely manner. Death as a result of autoimmune hemolytic anemia is rare.

In many cases, the cause of autoimmune hemolytic anemia remains unknown. Some researchers believe that there are multiple factors involved, including genetic and environmental influences (multifactorial). In a very small number of cases, autoimmune hemolytic anemia appears to run in families. In these cases, it appears to follow an autosomal recessive pattern of inheritance.

If you have concerns about the specific risks in your family, we encourage you to consult with a genetics professional.