Friday, March 20, 2020
What Are Thalassemias Essays
What Are Thalassemias Essays What Are Thalassemias Essay What Are Thalassemias Essay Thalassemias (thal of an Inheritance Pattern for Alpha Thalassemia The picture shows one example of how alpha thalassemia is inherited.The alpha globin genes are located on chromosome 16. A child inherits four alpha globin genes (two from each parent). In this example, the father is missing two alpha globin genes and the mother is missing one alpha globin gene. Each child has a 25 percent chance of inheriting two missing genes and two normal genes (thalassemia trait), three missing genes and one normal gene (hemoglobin H disease), four normal genes (no anemia), or one missing gene and three normal genes (silent carrier). Beta Thalassemias You need two genes (one from each parent) to make enough beta globin protein chains.If one or both of these genes are altered, youll have beta thalassemia. This means that your body wonââ¬â¢t make enough beta globin protein. * If you have one altered gene, youre a carrier. This condition is called beta thalassemia trait or beta thalassemia minor. It causes mild anemia. * If both genes are altered, youll have beta thalassemia intermedia or beta thalassemia major (also called Cooleys anemia). The intermedia form of the disorder causes moderate anemia. The major form causes severe anemia. Example of an Inheritance Pattern for Beta ThalassemiaThe picture shows one example of how beta thalassemia is inherited. The beta globin gene is located on chromosome 11. A child inherits two beta globin genes (one from each parent). In this example, each parent has one altered beta globin gene. Each child has a 25 percent chance of inheriting two normal genes (no anemia), a 50 percent chance of inheriting one altered gene and one normal gene (beta thalassemia trait), or a 25 percent chance of inheriting two altered genes (beta thalassemia major). Who Is at Risk for Thalassemias? Family history and ancestry are the two risk factors for thalassemias.Family History Thalassemias are inherited- that is, the genes for the disorders are passed from parents to their children. If your parents have missing or altered hemoglobin-making genes, you may have thalassemia. Ancestry Thalassemias occur most often among people of Italian, Greek, Middle Eastern, Southern Asian, and African descent. What Are the Signs and Symptoms of Thalassemias? A lack of oxygen in the bloodstream causes the signs and symptoms of thalassemias. The lack of oxygen occurs because the body doesnt make enough healthy red blood cells and hemoglobin.The severity of symptoms depends on the severity of the disorder. No Symptoms Alpha thalassemia silent carriers generally have no signs or symptoms of the disorder. The lack of alpha globin protein is so minor that the bodys hemoglobin works normally. Mild Anemia People who have alpha or beta thalassemia trait can have mildà anemia. However, many people who have these types of thalassemia have no signs or symptoms. Mild anemia can make you feel tired. Mild anemia caused by alpha thalassemi a trait might be mistaken forà iron-deficiency anemia. Mild to Moderate Anemia and Other Signs and SymptomsPeople who have beta thalassemia intermedia have mild to moderate anemia. They also may have other health problems, such as: * Slowed growth and delayed puberty. Anemia can slow down a childs growth and development. * Bone problems. Thalassemia may cause bone marrow to expand. Bone marrow is the spongy substance inside bones that makes blood cells. When bone marrow expands, the bones become wider than normal. They may become brittle and break easily. * An enlarged spleen. The spleen is an organ that helps your body fight infection and remove unwanted material.When a person has thalassemia, the spleen has to work very hard. As a result, the spleen becomes larger than normal. This makes anemia worse. If the spleen becomes too large, it must be removed. Severe Anemia and Other Signs and Symptoms People who have hemoglobin H disease or beta thalassemia major (also called Cooleys anemia) have severe thalassemia. Signs and symptoms usually occur within the first 2à years of life. They may include severe anemia and other health problems, such as: * A pale and listless appearance * Poor appetite Dark urine (a sign that red blood cells are breaking down) * Slowed growth and delayed puberty * Jaundice (a yellowish color of the skin or whites of the eyes) * An enlarged spleen, liver, or heart * Bone problems (especially with bones in the face) Complications of Thalassemias Better treatments now allow people who have moderate and severe thalassemias to live much longer. As a result, these people must cope with complications of these disorders that occur over time. Heart and Liver Diseases Regularà blood transfusionsà are a standard treatment for thalassemias.Transfusions can cause iron to build up in the blood (iron overload). This can damage organs and tissues, especially the heart and liver. Heart disease caused by iron overload is the main cause of death i n people who have thalassemias. Heart disease includesà heart failure,à arrhythmiasà (irregular heartbeats), andà heart attack. Infection Among people who have thalassemias, infections are a key cause of illness and the second most common cause of death. People who have had their spleens removed are at even higher risk because they no longer have this infection-fighting organ.Osteoporosis Many people who have thalassemias have bone problems, including osteoporosis (OS-te-o-po-RO-sis). This is a condition in which bones are weak and brittle and break easily. How Are Thalassemias Diagnosed? Doctors diagnose thalassemias usingà blood tests, including a complete blood count (CBC) and special hemoglobin tests. * A CBC measures the amount of hemoglobin and the different kinds of blood cells, such as red blood cells, in a sample of blood. People who have thalassemias have fewer healthy red blood cells and less hemoglobin than normal in their blood.People who have alpha or beta th alassemia trait may have red blood cells that are smaller than normal. * Hemoglobin tests measure the types of hemoglobin in a blood sample. People who have thalassemias have problems with the alpha or beta globin protein chains of hemoglobin. Moderate and severe thalassemias usually are diagnosed in early childhood. This is because signs and symptoms, including severeà anemia, often occur within the first 2à years of life. People who have milder forms of thalassemia might be diagnosed after a routine blood test shows they have anemia.Doctors might suspect thalassemia if a person has anemia and is a member of an ethnic group thats at increased risk for thalassemias. (For more information, go toà Who Is at Risk for Thalassemias? ) Doctors also test the amount of iron in the blood to find out whether the anemia is due to iron deficiency or thalassemia. Iron-deficiency anemiaà occurs if the body doesnt have enough iron to make hemoglobin. The anemia in thalassemia occurs becaus e of a problem with either the alpha globin or beta globin chains of hemoglobin, not because of a lack of iron.Because thalassemias are passed from parents to children through genes, family genetic studies also can help diagnose the disorder. These studies involve taking a family medical history and doing blood tests on family members. The tests will show whether any family members have missing or altered hemoglobin genes. If you know of family members who have thalassemias and youre thinking of having children, consider talking with your doctor and a genetic counselor. They can help determine your risk for passing the disorder to your children. If youre expecting a baby and you and your partner are thalassemia carriers, you may ant to consider prenatal testing. Prenatal testing involves taking a sample of amniotic fluid or tissue from the placenta. (Amniotic fluid is the fluid in the sac surrounding a growing embryo. The placenta is the organ that attaches the umbilical cord to the mothers womb. ) Tests done on the fluid or tissue can show whether your baby has thalassemia and how severe it might be. How Are Thalassemias Treated? Treatments for thalassemias depend on the type and severity of the disorder. People who are carriers or who have alpha or beta thalassemia trait have mild or no symptoms. Theyââ¬â¢ll likely need little or no treatment.Doctors use three standard treatments for moderate and severe forms of thalassemia. These treatments includeà blood transfusions, iron chelation (ke-LAY-shun) therapy, and folic acid supplements. Other treatments have been developed or are being tested, but theyre used much less often. Standard Treatments Blood Transfusions Transfusions of red blood cells are the main treatment for people who have moderate or severe thalassemias. This treatment gives you healthy red blood cells with normal hemoglobin. During a blood transfusion, a needle is used to insert an intravenous (IV) line into one of your blood vessels.Thro ugh this line, you receive healthy blood. The procedure usually takes 1 to 4 hours. Red blood cells live only for about 120 days. So, you may need repeated transfusions to maintain a healthy supply of red blood cells. If you have hemoglobin H disease or beta thalassemia intermedia, you may need blood transfusions on occasion. For example, you may have transfusions when you have an infection or other illness, or when yourà anemiaà is severe enough to cause tiredness. If you have beta thalassemia major (Cooleys anemia), youââ¬â¢ll likely need regular blood transfusions (often every 2 to 4 weeks).These transfusions will help you maintain normal hemoglobin and red blood cell levels. Blood transfusions allow you to feel better, enjoy normal activities, and live into adulthood. This treatment is lifesaving, but its expensive and carries a risk of transmitting infections and viruses (for example, hepatitis). However, the risk is very low in the United States because of careful blood screening. For more information, go to the Health Topicsà Blood Transfusionà article. Iron Chelation Therapy The hemoglobin in red blood cells is an iron-rich protein.Thus, regular blood transfusions can lead to a buildup of iron in the blood. This condition is called iron overload. It damages the liver, heart, and other parts of the body. To prevent this damage, doctors use iron chelation therapy to remove excess iron from the body. Two medicines are used for iron chelation therapy. * Deferoxamine is a liquid medicine thats given slowly under the skin, usually with a small portable pump used overnight. This therapy takes time and can be mildly painful. Side effects include problems with vision and hearing. * Deferasirox is a pill taken once daily.Side effects include headache, nausea (feeling sick to the stomach), vomiting, diarrhea, joint pain, and tiredness. Folic Acid Supplements Folic acid is a B vitamin that helps build healthy red blood cells. Your doctor may recommend f olic acid supplements in addition to treatment with blood transfusions and/or iron chelation therapy. Other Treatments Other treatments for thalassemias have been developed or are being tested, but theyre used much less often. Blood and Marrow Stem Cell Transplant A blood and marrow stem cell transplant replaces faulty stem cells with healthy ones from another person (a donor).Stem cells are the cells inside bone marrow that make red blood cells and other types of blood cells. A stem cell transplant is the only treatment that can cure thalassemia. But only a small number of people who have severe thalassemias are able to find a good donor match and have the risky procedure. For more information, go to the Health Topicsà Blood and Marrow Stem Cell Transplantà article. Possible Future Treatments Researchers are working to find new treatments for thalassemias. For example, it might be possible someday to insert a normal hemoglobin gene into stem cells in bone marrow.This will allow people who have thalassemias to make their own healthy red blood cells and hemoglobin. Researchers also are studying ways to trigger a persons ability to make fetal hemoglobin after birth. This type of hemoglobin is found in fetuses and newborns. After birth, the body switches to making adult hemoglobin. Making more fetal hemoglobin might make up for the lack of healthy adult hemoglobin. Treating Complications Better treatments now allow people who have moderate and severe thalassemias to live longer. As a result, these people must cope with complications that occur over time.An important part of managing thalassemias is treating complications. Treatment might be needed for heart or liver diseases, infections, osteoporosis, and other health problems. How Can Thalassemias Be Prevented? You canââ¬â¢t prevent thalassemias because theyââ¬â¢re inherited (passed from parents to children through genes). However, prenatal tests can detect these blood disorders before birth. Family ge netic studies may help find out whether people have missing or altered hemoglobin genes that cause thalassemias. (For more information, go toà How Are Thalassemias Diagnosed? ) If you know of family members who have thalassemias and youre thinking of having children, consider talking with your doctor and a genetic counselor. They can help determine your risk for passing the disorder to your children. Living With Thalassemias Survival and quality of life have improved for people who have moderate or severe thalassemias. This is because: * More people are able to getà blood transfusionsà now. * Blood screening has reduced the number of infections from blood transfusions. Also, treatments for other kinds of infections have improved. * Iron chelation treatments are available that are easier for some people to take. Some people have been cured throughà blood and marrow stem cell transplants. Living with thalassemia can be challenging, but several approaches can help you cope. Fol low Your Treatment Plan Following the treatment plan your doctor gives you is important. For example, get blood transfusions as your doctor recommends, and take your iron chelation medicine as prescribed. Iron chelation treatment can take time and be mildly painful. However, dont stop taking your medicine. The leading cause of death among people who have thalassemias is heart disease caused by iron overload.Iron buildup can damage your heart, liver, and other organs. Several chelation treatments are now available, including injections and pills. Your doctor will talk with you about which treatment is best for you. Take folic acid supplements if your doctor prescribes them. Folic acid is a B vitamin that helps build healthy red blood cells. Also, talk with your doctor about whether you need other vitamin or mineral supplements, such as vitamins A, C, or D or selenium. Get Ongoing Medical Care Keep your scheduled medical appointments, and get any tests that your doctor recommends. The se tests may include: Monthly complete blood counts and tests for blood iron levels every 3 months * Yearly tests for heart function, liver function, and viral infections (for example, hepatitis B and C and HIV) * Yearly tests to check for iron buildup in your liver * Yearly vision and hearing tests * Regular checkups to make sure blood transfusions are working * Other tests as needed (such asà lung function tests, genetic tests, and tests to match your tissues with a possible donor if a stem cell transplant is being considered) Children who have thalassemias should receive yearly checkups to monitor their growth and development.The checkups include a physical exam, including a height and weight check, and any necessary tests. Take Steps To Stay Healthy Take steps to stay as healthy as possible. Follow a healthy eating plan and your doctors instructions for taking iron supplements. Get vaccinations as needed, especially if youve had your spleen removed. You may need vaccines for t he flu,à pneumonia, hepatitis B, and meningitis. Your doctor will advise you about which vaccines you need. Watch for signs of infection (such as a fever) and take steps to lower your risk for infection (especially if youve had your spleen removed).For example: * Wash your hands often. * Avoid crowds during cold and flu season. * Keep the skin around the site where you get blood transfusions as clean as possible. * Call your doctor if a fever develops. Emotional Issues and Support If you or your child has thalassemia, you may have fear, anxiety, depression, or stress. Talk about how you feel with your health care team. Talking to a professional counselor also can help. If youââ¬â¢re very depressed, your doctor may recommend medicines or other treatments that can improve your quality of life.Joining a patient support group may help you adjust to living with thalassemia. You can see how other people who have the same symptoms have coped with them. Talk with your doctor about loca l support groups or check with an area medical center. Support from family and friends also can help relieve stress and anxiety. Let your loved ones know how you feel and what they can do to help you. Some teens and young adults who have thalassemias may have a hard time moving from pediatric care to adult care.Doctors and other health professionals who care for these children might not be familiar with adult issues related to the disorder, such as certain complications. Also, it might be hard for adults who have thalassemias to find doctors who specialize in treating the disorder. Ask your childs doctor to help you find a doctor who can care for your child when the time comes to make the switch. Planning and good communication can help this move go smoothly. nhlbi. nih. gov/health/health-topics/topics/thalassemia/trials. html
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