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Living With Thalassemias

Survival and quality of life are now much better for people who have moderate or severe forms of thalassemia. This is because: * More people are able to get blood transfusions now. * Blood screening has reduced the number of infections from blood transfusions. Also, treatments for other kinds of infections have improved. * New iron chelation treatments are available that are easier for some people to take. * Some people have been cured through blood and marrow stem cell transplants. Living with thalassemia can be challenging, but several approaches can help you cope. Follow Your Treatment Plan It's important to follow the treatment plan your doctor gives you. Get blood transfusions as he or she recommends. Take your iron chelation medicine. This is important because the leading cause of death among people with thalassemias is heart disease caused by iron overload. Iron buildup can damage your heart, liver, and other organs. Although the iron chelation treatment can

Beta Thalassemias

Two genes (one from each parent) are needed to make enough beta globin protein chains. If one or both of these genes are altered, you will have beta thalassemia. This means that you don't make enough beta globin protein. If you have one altered gene, you're a carrier. This condition is called beta thalassemia trait or beta thalassemia minor. It causes mild anemia. If both genes are altered, you will have beta thalassemia intermedia or beta thalassemia major (also called Cooley's anemia). The intermedia form of the disorder causes moderate anemia. The major form causes severe anemia.

Alpha Thalassemias

Four genes (two from each parent) are needed to make enough alpha globin protein chains. If one or more of the genes is missing, you will have alpha thalassemia trait or disease. This means that you don't make enough alpha globin protein. * If you have only one missing gene, you're a silent carrier and won't have any signs of illness. * If you have two missing genes, you have alpha thalassemia trait (also called alpha thalassemia minor). You may have mild anemia. * If you have three missing genes, you likely will have hemoglobin H disease (which a blood test can detect). This form of thalassemia causes moderate to severe anemia. Very rarely, a baby will have all four genes missing. This condition is called alpha thalassemia major or hydrops fetalis. Babies with hydrops fetalis usually die before or shortly after birth.

Key Points

* Thalassemias are inherited blood disorders. "Inherited" means they're passed on from parents to children. * Thalassemias cause the body to make fewer healthy red blood cells and less hemoglobin than normal. * People who have thalassemias can have mild or severe anemia. This condition is caused by a lower than normal number of red blood cells or not enough hemoglobin in the red blood cells. * The two major types of thalassemia are alpha thalassemia and beta thalassemia. There are different forms of each type. * Thalassemias occur when the genes that control the production of hemoglobin are missing or altered. Your body won't work properly if your red blood cells don't make enough healthy hemoglobin. * Family history and ancestry are the two risk factors for thalassemias. If your parents have missing or altered hemoglobin-making genes, you may have thalassemia. Thalassemias occur most often among people of Italian, Greek, Middle Eastern, Asia

What Causes Thalassemias?

Your body makes three types of blood cells: red blood cells, white blood cells, and platelets (PLATE-lets). Red blood cells contain hemoglobin, an iron-rich protein that carries oxygen from your lungs to all parts of your body. Hemoglobin also carries carbon dioxide (a waste gas) from your body to your lungs to be exhaled. Hemoglobin has two kinds of protein chains: alpha globin and beta globin. If your body doesn't make enough of these protein chains, red blood cells don't form properly and can't carry enough oxygen. Your body won't work well if your red blood cells don't make enough healthy hemoglobin. Genes control how the body makes hemoglobin protein chains. When these genes are missing or altered, thalassemias occur. Thalassemias are inherited disorders. That is, they're passed on from parents to their children through genes. People who get abnormal hemoglobin genes from one parent but normal genes from the other are called carriers. Carriers often have no

Can Thalassemias Be Prevented?

Thalassemias can't be prevented because they're inherited (passed on from parents to children). However, these bleeding disorders can be found before birth through prenatal tests. Family genetic studies may help find out whether people have missing or altered hemoglobin genes that cause thalassemias. (For more information, see "How Are Thalassemias Diagnosed?") If you know of family members who have thalassemias and you're thinking of having children, consider talking with your doctor and/or a genetic counselor. They can help determine your risk for passing on the disorder to your child.

Innovations and Research

As one of five thalassemia centers in the United States designated by the National Institutes of Health, the Children's Hospital Boston thalassemia program provides patients with access to experts in the field and the most cutting-edge clinical trials available in the world. One promising recent study, now awaiting approval by the FDA, tested the effectiveness of a new oral iron chelator, deferisirox. Researchers from Children's Hospital Boston have been at the forefront of thalassemia research and treatment for decades. Important advances in the field that were made here include: • Recognition of the important role of hypertransfusion by Dr. David Nathan, Senior Associate in Hematology, in the 1960s. • Demonstration of effective iron chelation by subcutaneous pump deferoxamine (Desferal ®) by Dr. Richard Proper and David Nathan in the 1970s. • Elucidation of the molecular biology of thalassemia syndromes by Drs. Nathan, YW Kan, Stuart Orkin and others.

Treatments for Thalassemia

Increased understanding of thalassemia and careful medical management have transformed a disease that once was usually fatal into a chronic illness that requires varying degrees of medical care. Treatments for thalassemia range for each form of the illness. Milder versions of the disorder may call for no treatment except medical monitoring and perhaps genetic counseling as patients approach adulthood. More serious forms of thalassemia may require occasional or regular blood transfusions and chelation therapy to remove excess iron. Sometimes removal of the spleen is indicated. Careful monitoring of thalassemia patients, particularly those who have significant anemia or who require regular transfusions, is essential to preserve health and well-being. In addition to hematologists, thalassemia patients may require the care of a number of medical specialists who understand the disease and its particular implications. Specialists may include: cardiologists, endocrinologists, gastroenterologi

Diagnosis

Thalassemia can be diagnosed in different ways. Some types can be found on routine blood tests that show that the red blood cells are small or the patient is anemic. Testing of parents can be done before pregnancy to determine whether there is a risk of having a child with a severe form of thalassemia. The illness can be seen in sophisticated genetic testing, and can be found prenatally through amniocentesis or chorionic villus sampling (CVS).

Is there a test for thalassemia?

Blood tests and family genetic studies can show whether an individual has thalassemia or is a carrier. If both parents are carriers, they may want to consult with a genetic counselor for help in deciding whether to conceive or whether to have a fetus tested for thalassemia. Prenatal testing can be done around the 11th week of pregnancy using chorionic villi sampling (CVS). This involves removing a tiny piece of the placenta. Or, the fetus can be tested with amniocentesis around the 16th week of pregnancy. In this procedure, a needle is used to take a sample of the fluid surrounding the baby for testing. Assisted reproductive therapy is also an option for carriers who don't want to risk giving birth to a child with thalassemia. A new technique, pre-implantation genetic diagnosis (PGD), used in conjunction with in vitro fertilization, may enable parents who have thalassemia or carry the trait to give birth to healthy babies. Embryos created in-vitro are tested for the thalassemia gen

Gene Therapy Offers Hope for a Cure

\ Scientists are working to develop a gene therapy that may offer a cure for thalassemia. Such a treatment might involve inserting a normal beta globin gene (the gene that is abnormal in this disease) into the patient's stem cells, the immature bone marrow cells that are the precursors of all other cells in the blood. Another form of gene therapy could involve using drugs or other methods to reactivate the patient's genes that produce fetal hemoglobin - the form of hemoglobin found in fetuses and newborns. Scientists hope that spurring production of fetal hemoglobin will compensate for the patient's deficiency of adult hemoglobin.

Thalassemia Major: A Serious Disorder

The more severe form of the disease is thalassemia major, also called Cooley's Anemia. It is a serious disease that requires regular blood transfusions and extensive medical care. Those with thalassemia major usually show symptoms within the first two years of life. They become pale and listless and have poor appetites. They grow slowly and often develop jaundice. Without treatment, the spleen, liver and heart soon become greatly enlarged. Bones become thin and brittle. Heart failure and infection are the leading causes of death among children with untreated thalassemia major. The use of frequent blood transfusions and antibiotics has improved the outlook for children with thalassemia major. Frequent transfusions keep their hemoglobin levels near normal and prevent many of the complications of the disease. But repeated blood transfusions lead to iron overload - a buildup of iron in the body - that can damage the heart, liver and other organs. Drugs known as "iron chelators&quo

What do we know about heredity and thalassemia

Thalassemia is a group of inherited or genetic diseases that affect the body's ability to produce hemoglobin, usually resulting in anemia. Hemoglobin, a protein found in red blood cells, is necessary for carrying oxygen throughout the body. Thalassemia is passed to children by parents who carry the gene for the disease. There are many different types of thalassemia, ranging from mild to life-threatening or fatal without blood transfusions and appropriate treatment. Thalassemia trait, also known as Mediterranean anemia, is one of the most common genetic disorders. Rarely resulting in illness, it affects hundreds of millions of people around the world. Each year about 100,000 babies are born with severe forms of thalassemia. The disease occurs most often in people of Italian, Greek, Middle Eastern, South and Southeast Asian, and African ancestry. The type and severity of the illness is determined by the specific genetic abnormality present. Today, better understanding of the ca