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Idiopathic aplastic anemia

Contents of this page:


Bone marrow aspiration
Bone marrow aspiration

Alternative Names    Return to top

Anemia - idiopathic aplastic

Definition    Return to top

Idiopathic aplastic anemia is failure of the bone marrow to properly make blood cells.

See also:

Causes    Return to top

Bone marrow is the soft tissue in the center of bones. It helps form blood cells.

Aplastic anemia results from injury to the blood stem cell, a cell that develops into other blood cell types. The injury causes a reduction in the number of every type of blood cell in the body -- red cells, white cells, and platelets. Low numbers of red cells, white cells, and platelets is a condition called pancytopenia.

Idiopathic means the cause is unknown. However, idiopathic aplastic anemia is thought to occur when the body reacts against its own cells. This is called an autoimmune disorder.

The disease may be acute or chronic, and may get worse over time. There are no known risk factors.

Aplastic anemia may also be caused by certain medical conditions (such as pregnancy or lupus) or exposure to some toxins or drugs (including chemotherapy). See: Secondary (acquired) aplastic anemia

In some cases, aplastic anemia is associated with another blood disorder called paroxysmal nocturnal hemoglobinuria (PNH).

Symptoms    Return to top

Symptoms are the result of bone marrow failure and the loss of blood cell production.

Low red cell count (anemia) leads to fatigue and weakness.

Low white cell count (leukopenia) causes an increased risk of infection.

Low platelet count (thrombocytopenia) results in bleeding, especially of the mucous membranes and skin.

General symptoms include:

Exams and Tests    Return to top

Treatment    Return to top

Mild cases of aplastic anemia may be treated with supportive care or may require no treatment.

In moderate cases, blood transfusions and platelet transfusions will help correct the abnormal blood counts and relieve some symptoms.

Severe aplastic anemia, which is defined as a very low blood-cell count, is a life-threatening condition. Bone marrow transplant or stem cell transplant is recommended for severe disease in younger patients.

For older patients, or for those who do not have a matched bone marrow donor, Atgam or thymoglobulin are alternative treatments. These medicines suppress the body's immune system in a way that allows the bone marrow to once again make blood cells. Atgam may be used in combination with other drugs, such as cyclosporine, tacrolimus, and steroids. Cyclophosphamide (Cytoxan) is another drug that may be used in certain circumstances.

Outlook (Prognosis)    Return to top

Untreated aplastic anemia leads to rapid death. Bone marrow transplant has been successful in young people, with long term survival rates of about 80%. Older people have a survival rate of 40 - 70%.

Possible Complications    Return to top

When to Contact a Medical Professional    Return to top

Call your health care provider or go to the emergency room if bleeding occurs for no reason, or if bleeding is difficult to stop. Call if you notice frequent infections or unusual fatigue.

Prevention    Return to top

There is no known prevention for idiopathic aplastic anemia.

References    Return to top

Castro-Malaspina H, O'Reilly R. Aplastic anemia and related disorders. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 171.

Update Date: 2/12/2009

Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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