Tuesday, December 16, 2008

Autoimmune Hemolytic Anemia

(Hemolytic Anemia)
Definition
Autoimmune hemolytic anemia is a condition in which your body’s immune system mistakenly attacks its own red blood cells, causing them to disintegrate (hemolyse). This can be a serious, even lethal, condition that requires care from your doctor.
There are many causes of hemolysis, the breaking up of red blood cells. Some are congenital (eg, sickle cell disease ), some are due to other diseases, and some are caused by drugs, but they all lead to anemia. The autoimmune hemolytic anemias, of which there are many types, occur when antibodies attack red blood cells.
Red Blood Cells

Causes
In some cases of autoimmune hemolysis, medications may attach to red cells, leading to targeting for destruction by the immune system. The most common are penicillin and its relatives, cephalosporins, quinidine, and some anti-inflammatory drugs.
In most cases, however, abnormal immune function leads the body to attack normal red blood cells. Causes of the underlying abnormal immune function include:
• Drugs
o Alpha-methyldopa
o L-dopa
• Infections
o Viral infections (including mononucleosis )
o Mycoplasma pneumonia
• Cancers
o Leukemia
o Lymphoma ( Non-Hodgkin’s but also occasionally Hodgkin’s )
• Collagen-vascular (autoimmune) diseases (eg, lupus )
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition.
The following factors increase your chance of developing autoimmune hemolytic anemia:
• Recent viral infections
• Current medications of the types that can cause autoimmune hemolytic anemia
• Cancer or leukemia
• Collagen-vascular (autoimmune) disease
• Family history of hemolytic disease
Symptoms
If you experience any of these symptoms, do not assume the cause is due to autoimmune hemolytic anemia. These symptoms may be caused by many other health conditions. If you experience any one of them, see your physician.
• Dark brown urine
• Jaundice (yellow skin)
• Pallor (pale skin)
• Muscle pains
• Headache
• Nausea and vomiting
• Diarrhea
• Progressive weakness
• Shortness of breath
• Rapid heartbeat
Diagnosis
Your doctor will ask about your symptoms, medications, and medical history, and perform a physical exam. You will most likely be referred to a hematologist.
Tests may include the following:
• Extensive blood testing
• Urinalysis
Treatment
Talk with your doctor about the best treatment plan for you. Mild cases may need no treatment and resolve on their own. Treatment options include the following:
Treating the Underlying Condition
When autoimmune hemolytic anemia is caused by cancer, medications, or collagen-vascular disease, treating the underlying condition may suffice.
Corticosteroids
Cortisone-like drugs suppress the immune response and usually markedly improve autoimmune hemolytic anemia.
Other Immunusuppressive Drugs
If corticosteroids are not effective, other drugs that suppress the immune system may be used. These include azathioprine and cyclophosphamide.
Splenectomy
The spleen removes abnormal red cells from the circulation, including those labeled with antibodies. Removing the spleen can preserve those cells and prevent anemia.
Transfusion
If your blood gets too anemic, you will need transfusions.
Prevention
Because of the multiple possible causes of autoimmune hemolytic anemia, prevention is not a consideration.