Aplastic Anemia

Also known as Bone Marrow Failure
Aplastic anemia is a rare but serious blood disorder that occurs when your bone marrow cannot make enough new blood cells for your body to work normally.

Aplastic anemia occurs because of damage to stem cells inside bone marrow, which is the sponge-like tissue within your bones. Many diseases and conditions can damage the stem cells in bone marrow. As a result, the bone marrow makes fewer red blood cells, white blood cells, and platelets.

The most common cause of bone marrow damage is from your immune system attacking and destroying the stem cells in your bone marrow, which is a kind of autoimmune disorder. The genes you inherit from your parents, some medicines, and certain toxins in the environment may also cause aplastic anemia.

Aplastic anemia can develop suddenly or slowly, and it can be mild or severe. signs and symptoms of aplastic anemia include Fatigue, infections that last a long time, and easy bruising or bleeding. The low levels of blood cells also increase your risk for complications such as bleeding, leukemia, or other serious blood disorders. Without treatment, aplastic anemia can lead to serious medical conditions such as arrhythmia and heart failure. To diagnose aplastic anemia, your doctor will order tests to determine whether you have low numbers of cells in your bone marrow and blood.

Treatments may include medicines to suppress your immune system, blood transfusions, or a blood and bone marrow transplant. A blood and bone marrow transplant may cure the disorder in some people. Removing a known cause of aplastic anemia, such as exposure to a toxin, may also cure the condition. Because people who have aplastic anemia are more likely to develop blood disorders, your doctor will monitor your condition and screen you for blood disorders regularly. If you take medicine to suppress your immune system, you will also need to take steps to prevent infection and the flu, including taking medicine and getting vaccines such as an annual flu shot.

Visit Aplastic Anemia for more information about this topic.

Research for Your Health

The NHLBI is part of the U.S. Department of Health and Human Services’ National Institutes of Health (NIH)—the Nation’s biomedical research agency that makes important scientific discovery to improve health and save lives. We are committed to advancing science and translating discoveries into clinical practice to promote the prevention and treatment of heart, lung, blood, and sleep disorders including different types of anemia. Learn about the current and future NHLBI efforts to improve health through research and scientific discovery.

Improving health with current research
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Learn about the following ways the NHLBI continues to translate current research into improved health for people with aplastic anemia. Research on this topic is part of the NHLBI’s broader commitment to advancing blood disorders and blood safety scientific discovery.

  • Program Helps Protect Blood Transfusion Recipients. The NHLBI’s Recipient Epidemiology and Donor Evaluation Study (REDS) program began in 1989 to protect the Nation’s blood supply and improve the benefits and reduce the risks of transfusions. Now in its third phase, called REDS-III, the program supports research in the United States and around the world.
  • Providing Access to NHLBI Biologic Specimens and Data. The Biologic Specimen and Data Repository Information Coordinating Center (BioLINCC) centralizes and integrates biospecimens and clinical data that were once stored in separate repositories. Researchers can find and request available resources on BioLINCC’s secure website, which maximizes the value of these resources and advances heart, lung, blood, and sleep research.
  • Supporting Safe Manufacturing of Cell-based Therapies. The NHLBI’s Production Assistance for Cellular Therapies (PACT) program supports translational research on cellular and genetic therapies by increasing the capacity to manufacture cell products that follow current Good Manufacturing Practices (cGMP) regulations. The PACT program is designed to increase the supply and safety of genetically modified cells available for patients who have blood disorders such as aplastic anemia.
  • Network Accelerates Research on Blood and Bone Marrow Transplants. The NHLBI and the National Cancer Institute (NCI) launched the Blood and Marrow Transplant Clinical Trials Network (BMT CTN) in 2001 to promote large multi-institutional clinical trials that seek to understand the best possible treatment approaches in blood and marrow transplantation. In the United States, about 20,000 patients receive blood or marrow transplants annually.

Learn about some of the pioneering research contributions we have made over the years that have improved clinical care.

Advancing research for improved health
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In support of our mission, we are committed to advancing research on anemia, in part through the following ways.

Learn about exciting research areas the NHLBI is exploring for aplastic anemia.

Participate in NHLBI Clinical Trials

We lead or sponsor many studies on aplastic anemia. See whether you or someone you know is eligible to participate in our clinical trials.

Trials at the NIH Clinical Center

Blood disorder research

This study is collecting medical information from health exams and routine tests and procedures to see whether participants may be able to enroll in other studies on blood disorders. Participants in this study must be at least 8 years, with or without a blood disorder. This study is located in Bethesda, Maryland.

To learn more about clinical trials at the NIH Clinical Center or to talk to someone about a study that might fit your needs, call the Office of Patient Recruitment 800-411-1222.

Are you considering a blood stem cell transplant?

This study is investigating a new method for collecting blood stem cells from donors to see if it reduces transplant complications, such as rejection, in patients who have blood diseases. To participate in this study, you must have a well-matched donor; you and your donor must be between 4 and 80 years old; and you must not be a candidate for immunosuppressive therapy. This study is located in Bethesda, Maryland.

Do you or a family member have Diamond-Blackfan anemia?

This registry seeks to collect information from patients who have Diamond-Blackfan anemia (DBA), in order to help researchers and doctors learn more about the condition. The registry will also help connect patients with DBA to research and clinical studies, and possible treatment options. The registry accepts all patients diagnosed with DBA.
View more information about Diamond-Blackfan Anemia Registry (DBAR).

Have you or your child been diagnosed with aplastic anemia but not been treated yet?

This study is testing whether adding the medicine eltrombopag to standard treatments is a better way to treat severe aplastic anemia. Participants in this study must be 2 years or older and have severe aplastic anemia that has not yet been treated. This study is located in Bethesda, Maryland.

Have you received a stem cell transplant?

This study aims to monitor the long-term health of patients who have received a donor stem cell transplant from the NIH Clinical Center. To participate in this study, you must be between 10 and 80 years old and had your transplant more than 3 years ago. This study is located in Bethesda, Maryland.

Do you have short telomeres and a telomere gene mutation?

Some people who have aplastic anemia have very short telomeres, which protect the ends of DNA in chromosomes. This study is testing whether low doses of the medicine danazol help prevent telomeres from getting shorter and reduce signs of damage from aplastic anemia or related conditions. Participants in this study must be 3 years or older and have a telomere disease and signs of aplastic anemia, lung disease such as pulmonary fibrosis, or liver disease. This study is located in Bethesda, Maryland.

Do you lack a well-matched donor for a blood and bone marrow transplant?

This study aims to determine whether a transplant of umbilical cord blood from an unrelated donor or a blood and bone marrow transplant from a partial match donor are suitable alternatives for people who do not have a well-matched donor. To participate in this study, you must be younger than 75, have severe aplastic anemia, have tried immunosuppressants without success, and not have a well-matched donor. This study is located in 28 cities across the United States.

Are you or your child taking cyclosporine for aplastic anemia?

This study is testing whether the medicine sirolimus helps prevent the return of aplastic anemia after stopping cyclosporine. Participants in this study must be 2 years or older and have severe aplastic anemia. This study is located in Bethesda, Maryland.

Are you scheduled for a stem cell transplant with cord blood?

This study will assess the safety and effectiveness of certain cord blood transplants. The study will help researchers learn the best methods for collecting, storing, and using cord blood in transplants. To participate in this study, you must have a disorder that compromises your body’s ability to make blood cells. This study is located in Bethesda, Maryland.

More Information

After reading our Aplastic Anemia Health Topic, you may be interested in additional information found in the following resources.

Non-NHLBI resources
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Image of the cover of the January edition of the Transfusion journal
Credit: Transfusion journal
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