What is thalassemia?

Thalassemia (thal-uh-SEE-me-uh) is a problem with red blood cells that is passed down from parents to children (inherited).

Thalassemia can cause low levels of red blood cells (anemia).  A child with thalassemia has a long-lasting anemia that may be mistaken for anemia caused by lack of iron

The anemia caused by thalassemia can vary from mild to severe. Children with the most severe forms need repeated transfusions of red blood cells.

  • What causes thalassemia?

    Red blood cells have a protein called hemoglobin (HEE-meh-gloh-bin) that carries oxygen. Multiple genes direct how the body makes hemoglobin. In thalassemia, 1 or more of those genes is missing or changed (mutated). This change is passed down from parents to children. 

    How serious the disease is depends on how many genes are missing or abnormal. If both parents have thalassemia, their child may inherit more abnormal genes and have more severe anemia.

    Thalassemia happens most often in people of South Asian, Middle Eastern, Mediterranean and African descent.

Thalassemia at Seattle Children’s

At Seattle Children’s, we provide complete care for children with thalassemia. We work with you, your child, your family and your child's primary care provider to get your child the right care and services. We also counsel parents who want to know more about their chance of passing the abnormal genes down to their children.

If you would like an appointment, ask your primary care provider to refer you to our Cancer and Blood Disorders Center. If you have a referral or would like a second opinion, contact the center at 206-987-2106.


  • The experts you need for comprehensive care

    Our doctors are nationally known for treating children who have blood disorders. The doctors who will guide your child’s care are board certified in pediatric hematology. This means they are approved to give the specialized care your child needs and they constantly expand their knowledge about blood disorders.

    Our physician-scientists help set national standards for the care of young people with blood disorders. They are active in regional and national groups that work to improve care for patients with thalassemia. The knowledge we gain through research improves the care we give all children.  

    We carefully monitor your child’s health and provide treatments as needed. Seattle Children’s has the experts to treat health problems thalassemia may cause. These could affect the heart, bones, hormones, and digestive system. Regular checkups and timely treatment can help your child live a healthy, active life.

    Our genetic counselor can help identify other family members with the condition and explain the chance of passing it on in a future pregnancy.

  • Among the nation’s best children’s hospitals

    Our specialty is treating children’s conditions while helping them grow up to be healthy and productive. We provide the most advanced treatments in our region.

    Children do not react to illness, injury, pain and medicine in the same way as adults. They need — and deserve — care designed just for them. We plan your child’s treatment based on years of experience and the newest research on what works best — and most safely — for children.

    We care for your whole child. We do not just treat their disease. Our team also includes nurses, social workers and experts in nutrition, pharmacy and emotional health.  Read more about the supportive care we offer.

  • Advanced therapies, including stem cell transplants

    We offer the most advanced treatments in the region, including blood transfusions, medicines and transplants of blood-forming stem cells from a healthy donor.

    Our Non-Malignant Transplant Program specializes in stem cell transplants for children with noncancer conditions, including thalassemia. Our transplant team is very experienced in preparing children for stem cell transplant and helping them recover without serious side effects.

    See details on the number of stem cell transplants we do each year and survival rates for children who receive them.

    To do the transplants, we work closely with Fred Hutchinson Cancer Center. Fred Hutch pioneered stem cell transplants to treat blood disorders and is one of the largest stem cell transplant centers in the world.

  • Support for your whole family

    Having thalassemia can be stressful for the entire family. We help take positive steps right away by offering appointments within 1 to 3 days to new patients with urgent needs. If needs are not urgent, new patients can be seen in 1 or 2 weeks.

    During visits, we take time to explain your child’s condition. We help you fully understand your treatment options and make the choices that are right for your family.

    Our child life specialists and social workers help your child and your family through the challenges of this condition. We connect you to community resources and support groups.

    At Seattle Children's, we work with many children and families from around the Northwest and beyond. Whether you live nearby or far away, we can help with financial counseling, schooling, housing, transportation, interpreter services and spiritual care. Read about our services for patients and families.

Symptoms of Thalassemia

Some children with mild thalassemia have no symptoms at all. In other children, symptoms can range from mild to severe.

If your child’s red blood cell levels are a little lower than normal (mild anemia), they may have few symptoms.  Symptoms of anemia include:

  • Feeling tired or irritable
  • Being short of breath, dizzy or lightheaded
  • Having pale skin, lips or nail beds compared to their normal color

If your child’s anemia is more severe and it is not treated, they may also have these symptoms:

  • A liver or spleen that is larger than normal
  • Enlarged bones, mainly in the cheeks and forehead
  • Slowed growth, which may include later puberty
  • Heart failure

Diagnosing Thalassemia

Most newborns get blood tests that find certain types of thalassemia. But your child may not be diagnosed until later if they have a mild condition or a type of thalassemia that is not found by the newborn screen. The condition may be diagnosed when a routine blood test shows low levels of red blood cells (anemia) or small red blood cells (microcytosis).

Then the doctor will:

  • Ask about your child’s health and your family’s health history
  • Check your child’s growth
  • Check for an enlarged spleen
  • Do more blood tests to learn the cause of the anemia

The blood tests may:

  • Check for other types of anemia, such as iron-deficiency anemia
  • Measure the amounts and types of hemoglobin in your child’s blood (hemoglobin electrophoresis)
  • Look for genetic changes that help diagnose some forms of thalassemia
  • Genetic testing and counseling

    To help diagnose your child, your doctor may want to take a family medical history and test the blood of family members. The tests will show whether any family members have missing or changed hemoglobin genes.

    If a parent or other family member has thalassemia (or carries an abnormal gene), our genetic counselor can explain the chance of passing it on in a future pregnancy.

Treating Thalassemia

Your child’s treatment plan depends on their illness. Some children need little or no treatment because they have only mild symptoms or no symptoms at all.

Children with more serious disease will see a blood specialist more often for treatment and to watch for complications that may happen over time. 

We check your child as needed so they receive the right treatment at the right time. Seattle Children’s offers these treatments for thalassemia:

  • Regular check-ups

    If your child has a mild case, they may not need to see a blood specialist regularly. Your child’s primary care provider can give any treatment they might need.

    Children with more serious disease will visit every 3 to 12 months with a doctor who specializes in blood disorders.

    At visits, we check:

    • Any symptoms
    • Your child’s rate of growth
    • Their level of red blood cells
    • The size of their spleen, because the spleen gets larger if it is working too hard
    • The amount of body iron, which can become too high in patients with thalassemia
    • Hormone levels, which may be abnormal in children who have too much iron

    Keeping track of their health in this way helps ensure your child gets the care they need before more serious problems start. Regular health care can help prevent or treat complications that affect some children over time. Your child may need to see specialists if they have problems with their:

  • Blood transfusions

    Some children with thalassemia need red blood cells from a healthy donor (a blood transfusion). Giving your child healthy red blood cells helps them get the oxygen their body needs.

    How often your child might need a transfusion depends on their disease.

    • Some children only need a transfusion at certain times, such as when they have a major illness or infection.
    • Children with severe forms of beta thalassemia must have blood transfusions every 3 to 4 weeks throughout their life, unless they are cured with a stem cell transplant. This form of the disease is also called thalassemia major or transfusion-dependent thalassemia.

    Your child will receive the blood by IV or a central line. They can get transfusions without having to spend a night in the hospital. Our outpatient infusion unit is staffed by expert nurses and is open every day.

    Chelation therapy for iron overload

    Transfused blood contains iron. After a child gets many transfusions, the iron builds up in some of their organs. This is called iron overload. The iron buildup can harm the heart, liver and glands that make hormones.

    Your doctor will check your child's iron level regularly. If it starts to get too high, your child will need a treatment called chelation therapy to remove the extra iron. They will need to take medicine that binds to iron. This allows the extra iron to leave the body in the pee (urine) or bowel movement (stool).

  • Stem cell transplant

    For children with serious disease who often need transfusions, treatment options may include a transplant of blood-forming stem cells from a healthy donor. A transplant can cure thalassemia because the new cells help your child’s bone marrow make normal blood cells. This is also called a bone marrow transplant or hematopoietic (him-at-oh-poy-EH-tik) cell transplant.

    The transplant has a better chance of success if there is a close match between the cells of the donor and the child getting the transplant. Siblings are more likely to be a close match.

    Our Non-Malignant Transplant Program specializes in stem cell transplants for children with noncancer conditions. Children need special treatment, called conditioning, to prepare their body for the transplant and help them recover without serious side effects. Our team created many of the conditioning treatments used now. This includes less intense preparation called reduced-intensity conditioning.

    We perform the transplants here at Seattle Children’s, working closely with our partner Fred Hutch.

Contact Us 

If you would like an appointment, ask your child’s primary care provider to refer you.

If you have a referral or would like a second opinion, contact the Cancer and Blood Disorders Center at 206-987-2106 or by email.

Providers, see how to refer a patient.

For Healthcare Professionals