What is alpha thalassemia?
Thalassemia (thal-uh-SEE-mee-uh) is a blood disorder that is inherited. This means it is passed down from one or both parents through their genes. When you have thalassemia, your body makes less hemoglobin than normal. Hemoglobin is an iron-rich protein in red blood cells. It carries oxygen to all parts of the body.
There are 2 main types of thalassemia: alpha and beta. Different genes are affected for each type.
Thalassemia can cause mild or severe anemia. Anemia occurs when your body does not have enough red blood cells or hemoglobin. The severity and type of anemia depends on how many genes are affected.
What causes alpha thalassemia?
Alpha thalassemia occurs when some or all of the 4 genes that make hemoglobin (the alpha-globin genes) are missing or damaged.
There are 4 types of alpha thalassemia:
Alpha thalassemia silent carrier. One gene is missing or damaged, and the other 3 are normal. Blood tests are usually normal. Your red blood cells may be smaller than normal. Being a silent carrier means you don’t have signs of the disease, but you can pass the damaged gene on to your child. This is confirmed by DNA tests.
Alpha thalassemia carrier. Two genes are missing. You may have mild anemia.
Hemoglobin H disease. Three genes are missing. This leaves just 1 working gene. You may have moderate to severe anemia. Symptoms can worsen with fever. They can also get worse if you are exposed to certain medicines, chemicals, or infectious agents. Blood transfusions are often needed. You have a greater risk of having a child with alpha thalassemia major.
Alpha thalassemia major. All 4 genes are missing. This causes severe anemia. In most cases, a baby with this condition will die before birth.
Who is at risk for alpha thalassemia?
This is a genetic disease inherited from one or both parents. The only risk factor is having a family history of the disease.
What are the symptoms of alpha thalassemia?
Different people will have different symptoms, based on which type of alpha thalassemia is inherited. Common symptoms for each type may include:
Silent alpha thalassemia carrier. This type has no symptoms.
Alpha thalassemia carrier. You may have mild anemia. You may have no symptoms. Or you may have mild symptoms such as mild fatigue or exercise intolerance.
Hemoglobin H disease. This type causes moderate to severe symptoms. These include lack of energy (fatigue) and exercise intolerance. You may also have an enlarged liver or spleen, yellowish skin, and leg ulcers. You have a greater risk of having a child with the most severe type, alpha thalassemia major.
Alpha thalassemia major. Babies with this type usually die before they are born.
How is alpha thalassemia diagnosed?
Alpha thalassemia is most commonly found in these parts of the world:
The following tests may help to tell if you are a carrier, and can pass the disorder on to your children:
Complete blood count (CBC). This test checks the size, number, and maturity of different blood cells in a set volume of blood.
Hemoglobin electrophoresis with A2 and F quantitation. A lab test that tells what type of hemoglobin is present.
FEP (free-erythrocyte protoporphyrin) and ferritin. This test is done to rule out iron-deficiency anemia.
All of these tests can be done using a single blood sample. In a pregnant woman, the baby is diagnosed using CVS (chorionic villus sampling) or amniocentesis. A DNA test is needed to make a diagnosis of alpha thalassemia.
How is alpha thalassemia treated?
Your healthcare provider will figure out the best treatment for you based on:
Your age, overall health, and medical history
How sick you are
How well you can handle certain medicines, procedures, or therapies
How long the condition is expected to last
Your opinion or preference
Treatment may include:
Daily doses of folic acid
Blood transfusions (as needed)
Surgery to remove your spleen
Medicines to reduce extra iron from your body (called iron chelation therapy)
Avoidance of certain oxidant drugs in hemoglobin H disease
Living with alpha thalassemia
People with alpha thalassemia may have no symptoms. Or they may have many symptoms. If you don’t have symptoms, you may still want to see a specialist. He or she can help you understand the risks of passing the disease to your children.
If you have symptoms, work with your healthcare provider. He or she can help you find the best treatment to reduce anemia symptoms.
Key points about alpha thalassemia
A thalassemia is an inherited blood disorder. It causes the body to make less hemoglobin than normal.
There are 4 different types of alpha thalassemia.
This condition causes mild to severe anemia, based on the type of alpha thalassemia that is inherited.
People who have this condition can pass the disease on to their children.
There is no cure. Treatment can reduce symptoms.