Thalassemia

Thalassemia (thal-uh-SEE-me-uh) is a blood disorder. It's inherited, which means it's passed from parents to children through genes. Genes carry information that can affect many things, including what people look like and whether they might have certain diseases.

Thalassemia causes the body to have less of the protein hemoglobin than usual. Hemoglobin is present in red blood cells and allows the red blood cells to carry oxygen. Not having enough hemoglobin or red blood cells can lead to a condition called anemia. That can make you feel tired and weak.

If you have a mild form of thalassemia called thalassemia trait, you do not need any specific treatment. But with more-serious forms, you might need regular blood transfusions. Those are treatments in which you receive blood from a donor. Lifestyle changes also are key. For instance, a healthy diet and regular exercise can help you manage tiredness.

There are different types of thalassemia. The symptoms that you have depend on the type and how serious it is.

Symptoms of severe thalassemia can include:

• Tiredness, also called fatigue.
• Weakness.
• A change in skin color or a yellowing of skin and eyes.
• Changes or problems with facial bones.
• Slow growth.
• Swelling of the stomach area, also called the abdomen.
• Dark urine.
• Poor appetite.

Some babies show symptoms of thalassemia at birth. Others get symptoms during the first two years of life. But some people with thalassemia don't have symptoms.

Make an appointment with your child's health care team for a checkup if your child has any of the symptoms of thalassemia.

Thalassemia is caused by gene changes in cells that make hemoglobin. Hemoglobin is the protein in red blood cells that carries oxygen throughout the body. The gene changes linked with thalassemia are passed from parents to children.

Hemoglobin molecules are made of protein chains called alpha and beta chains. These chains are affected by gene changes. With thalassemia, the body doesn't make enough of either the alpha or the beta chains. That causes you to get either alpha-thalassemia or beta-thalassemia, the two main types of the condition.

In beta-thalassemia, the gene change is an alteration in the DNA. Other terms used to describe these changes include mutation or variation. In alpha-thalassemia, the altered DNA consists of missing one or more copies of the four genes that program the alpha chain. This also is termed "deletion."

With alpha-thalassemia, the seriousness of the condition depends on the number of missing genes you inherit from your parents. The more missing copies of the genes, the worse your thalassemia.

With beta-thalassemia, the seriousness of the condition depends on which part of the hemoglobin molecule is affected.

Alpha-thalassemia

Four genes are involved in making the alpha hemoglobin chain. You get two from each of your parents. The seriousness of alpha-thalassemia depends on how many copies of the genes are missing:

• If one copy of the gene is missing, you'll have no symptoms of thalassemia. But you carry the disease and can pass it on to your children.
• If two copies of the genes are missing, your thalassemia symptoms likely will be mild. You might hear this condition called alpha-thalassemia trait.
• If three copies of the genes are missing, your symptoms likely will be moderate to severe.

It's rare to be missing all four copies of the genes. It usually leads to stillbirth. That's the loss of a pregnancy at or after 20 weeks. Babies born with four missing genes often die shortly after birth. Or they need blood transfusions for the rest of their lives. Sometimes, a child born with this condition can be treated with blood transfusions and a stem cell transplant.

Beta-thalassemia

Two genes are involved in making the beta hemoglobin chain. You get one from each of your parents. Unlike the missing genes that cause alpha-thalassemia, small changes in the gene cause beta-thalassemia. These changes lead to reduced production of the beta chain. If you inherit:

• One gene with changes, you'll usually have mild symptoms. This condition is called nontransfusion-dependent thalassemia. If you have no symptoms, you may hear your condition called beta-thalassemia trait or thalassemia minor.

• Two genes with changes, your symptoms typically will be moderate to severe. This condition is called transfusion-dependent beta-thalassemia or thalassemia major.

  Babies born with two changed beta hemoglobin genes usually are healthy at birth. They often get symptoms within the first two years of life. But it is possible to get a milder form of the disease with two changed genes.

Factors that raise your risk of thalassemia include:

• Family history of thalassemia. The condition passes from parents to children through genetic changes in hemoglobin genes.
• Certain ancestry. Thalassemia happens most often in people of South Asian, Italian, Greek, Middle Eastern or African descent.

Health problems that can stem from moderate to severe thalassemia include:

• Iron overload. People with thalassemia can get too much iron in their bodies. This can be due to the disease or to frequent blood transfusions. Too much iron can result in damage to the heart, liver, and glands that make and release hormones.
• Infection. People with thalassemia have a higher risk of infections. This is especially true if they've had their spleens removed.

Severe thalassemia can lead to the following health problems:

• Bone changes. Thalassemia can cause the spongy tissue inside some bones, called bone marrow, to expand. That makes bones widen. It can lead to an irregular bone structure, especially in the face and skull. Expanding bone marrow also makes bones thin and brittle. That raises the chance of broken bones.

• Enlarged spleen. The spleen is an organ that helps the body fight infection. It also helps remove old or damaged blood cells. Often, thalassemia happens along with the destruction of a large number of red blood cells. This causes the spleen to get bigger and work harder than usual.

  An enlarged spleen can make anemia worse. It also can reduce the life of red blood cells received in a transfusion. If your spleen grows too big, your health care professional might recommend surgery to remove it.

• Slowed growth rates. Anemia can slow a child's growth and delay puberty.
• Heart problems. Congestive heart failure and irregular heart rhythms can be linked with severe thalassemia.

Most of the time, you can't prevent thalassemia. If you have the condition or if you have the thalassemia gene changes that cause it, it is very important to talk with a genetic counselor. The counselor can offer advice on the risks of your children being affected.

Some people with thalassemia major think about getting pregnant with assisted reproductive technology. This includes procedures such as in vitro fertilization. IVF joins an egg and a sperm outside the body to make the earliest stage of an unborn baby, called an embryo. An exam called preimplantation genetic testing can then be used to check the embryo for gene changes related to thalassemia. If an embryo doesn't have these changes, it can be placed in the uterus to start a pregnancy. This might help people who have thalassemia or a related gene have healthy babies.

Another procedure that might lead to pregnancy is called intrauterine insemination. Sperm from a donor who doesn't have thalassemia or the genes related the condition is placed in the uterus to join with an egg.