Early referral for comprehensive care before onset of illness. Screening for alphathalassemia is focused on prenatal counseling and diagnosis and on newborn screening. It is commonly mistaken for iron deficiency which also causes anemia. Mothers who are carriers for the alpha thalassemia mutation and whose fetuses develop signs of anemia should undergo additional testing for con. Genetic testing can help with this diagnosis, since severity of. Detecting and reporting alpha thalassemia in newborns aphl. Thalassemias involving delta, gamma, epsilon, and zeta chains are rare and usually not associated with significant disease outside of the neonatal period. In people with the characteristic features of alpha thalassemia, a reduction in the amount of hemoglobin prevents enough oxygen from reaching the bodys tissues. Laboratory diagnosis of hemoglobinopathies and thalassemia. Favorable outcomes after in utero transfusion in fetuses with.
If you have problems viewing pdf files, download the latest version of adobe reader. Folic acid supplementation 1 mgday orally avoid medicinal iron and oxidative drugs, such as sulfonamides. Sickle cell disease and hemoglobinopathy screening in pregnancy. The forms of beta thalassaemia with normal haemoglobin a2.
Postnatal stem cell transplantation can be a definitive therapy but has numerous complications. Heterozygotes with defects in two of the four genes result in alpha thalassemia trait, and tend to develop mild to moderate microcytic anemia but with no symptoms. Thalasemia tipe ini merupakan kondisi yang paling berbahaya pada thalassemia tipe alfa. Alpha thalassemia an overview sciencedirect topics. Four alpha globin genes are normally present 2 on each chromosome 16. Alpha thalassemia major atm is a genetic blood disorder that causes hemoglobin deficiency. The treatment of thalassaemia major and intermedia has traditionally depended on preventing undesirable. The aim of this report is to describe a case of plastic bronchitis in a child with alphathalassemia that was treated successfully with.
What if one parent has alpha thalassemia trait and the other parent is a silent carrier. People who have this condition can pass the disease on to their children. When parents are carriers of the cis deletion, there is a one in four, or 25 percent, chance with each pregnancy, to have a baby with alpha thalassemia major. Thalassemia quantitative a quantitative decrease in the production of alpha or beta globin chain large deletions, point mutations, small insertiondeletion that leads to decreased transcription or an unstable transcript beta thalassemia results from mutations in beta genes pathogenesis a result of the free alpha subunits. The main types are the beta thalassemia, alpha thalassemia and hemoglobin e. Of thalassemia major patients, 28 50% were boys and 28 50% were girls. The diagnosis of alpha thalassemia is made by excluding other causes of microcytosis, a positive family history of microcytic anemia, and a lifelong history of a microcytic anemia. Fiftysix of the patients were followed up with diagnoses of thalassemia major and 11 with thalassemia intermedia. Alpha thalassemia thal uh see mee uh trait is a condition that affects the amount of hemoglobin in the red blood cells.
Alpha thalassemia trait is an inherited abnormality of hemoglobin that results in a very mild anemia low blood hemoglobin level and smaller size of the red blood cells reduced mcv. Thalassemia knowledge for medical students and physicians. Establish a dialoguediscussion rather than a lecture or informationgiving format. For language access assistance, contact the ncats public information officer.
Regular visits to a comprehensive thalassemia center or a pediatric hematologist are crucial to the health and future well being of the baby. Alpha thalassemia 2 trait, also called the silent carrier is an asymptomatic carrier of a single alpha gene deletion. Janin yang menderita alpha thalassemia mayor pada awal. The alpha thalassemia are caused by a decrease in production of alpha globins chains due to deletion or mutation of one or more of the four alpha globins genes located on. Hb bart syndrome is characterized by hydrops fetalis, a condition in which excess fluid builds up in the. Alpha thalassemia results from large deletions in the alpha genes. Most cases of hemoglobin variants and alpha thalassemia are detected on the newborn screen, whereas beta thalassemia is not clinically apparent until about 46 months of life. Key difference sickle cell anemia vs thalassemia thalassemia is a heterogeneous group of disorders caused by. Carrier screening for individuals from highrisk populations for alpha thalassemia. Hemoglobin h disease alpha thalassemia information for physicians and other health care providers definition hemoglobin h disease is an inherited hemoglobin disorder in which three of the four alpha globin genes normally present are deleted or have a mutation which impairs alpha globin chain production. Screening of all newborns for hemoglobin h disease is justified in populations with a substantial number of atrisk. Thalassemias are a group of inherited blood conditions which result in the impaired production of hemoglobin, the molecule that carries oxygen in the blood. The following information is designed to help you learn. Individuals who have one or two abnormal alpha globin genes have alpha thalassemia trait.
The following are pdf formatted files in various languages. Alpha thalassemia normally, alpha globin chain is made by four genes two from each parent, two on each strand of chromosome 16. Additional labs vitamin levels fe battery, vit b12, folate ldh, bilirubin, haptoglobin coombs test hemoglobin electrophoresis. The alpha and beta refer to which haemoglobin gene is affected, and which of the haemoglobin chains is faulty. Alpha1 antitrypsin deficiency a guide for the recently diagnosed. Thalassemia can occur in all ethnic groups but is more common in those of southeast asian descent.
People with hemoglobin h disease can have an enlarged spleen, low. Laboratory diagnosis of thalassemia, which consists of blood film examinations and hemoglobin electrophoresis, are the most common modalities in our country since dna analysis for. All newborn screening programs are detecting alpha thalassemia. Patients with this condition have small red cells and a mild anemia but they do not have clear symptoms. The diagnosis of alpha 1 alpha 1 antitrypsin deficiency, also known as aat deficiency or alpha 1, is a medical diagnosis that should lead to open discussions with your doctor and family. Deletions account for approximately 90% of diseasecausing alleles in alpha thalassemia. Alpha thalassemia is a result of decreased production of alpha globins. Genetic and rare diseases information center gard po box 8126, gaithersburg, md 208988126. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. If an individual knows that she or he is a silent carrier.
Alpha thalassaemia is inherited as an autosomal recessive disorder characterised by a microcytic hypochromic anaemia, and a clinical phenotype varying from almost asymptomatic to a lethal haemolytic anaemia. It is important to have simple and reliable methods to identify unknown or rare deletions and. This condition causes mild to severe anemia, based on the type of alpha thalassemia that is inherited. Alphathalassemia is a blood disorder that reduces the bodys production of hemoglobin. This condition, in which one of the four alpha globin genes is missing or.
Two types of alphathalassemia can cause health problems. Adult hemoglobin hemoglobin a is made of alpha and beta globins. Affected people have anemia, which can cause pale skin, weakness, fatigue, and more serious complications. Beta thalassemia intermedia is a clinical diagnosis of a patient characterized by a less severe chronic anemia and a more variable clinical phenotype. Hemoglobin is the protein in red blood cells that carries oxygen to cells throughout the body. Diagnosis and treatment what is alpha thalassemia major. Jan 10, 2018 thalassemia is an inherited blood disorder. In individuals with atm, the red blood cells are missing normal hemoglobin and cannot deliver. Deletions and duplications, hemoglobin constant spring hbcs, and alpha thalassemia saudi point mutations only. Diagnosis of betathalassemia minor is confirmed by hba2 3. Thalassemia omim 141800 is the most common inherited disorder of hemoglobin hb synthesis in the world, with gene frequencies varying between 1% and 98% throughout the tropics and subtropics. Hemoglobin is a protein in red blood cells that carries oxygen throughout the body.
Many alphas, as individuals diagnosed with alpha 1 are known, live full and productive lives. An individual with one abnormal alpha globin gene is said to be a silent carrier of alpha thalassemia. Genetic studies dna analysis to investigate deletions and mutations in the alpha and betaglobinproducing gene help in correct diagnosis and improved management in thalassemic patients. Diagnosis of thalassemia disease prenatal diagnosis when both parents are known carriers of thalassemia mutation test second parent if one parent is known thalassemia trait prenatal testing cvs or amnio if both have beta trait or alpha trait no consequence if one parent has alpha and one has beta trait. The pathogenesis and treatment of alpha and beta thalassemia. Alpha thalassemia is distributed is a similar pattern to beta thalassemia except it very high frequency in africa up to 40%. Thalassemia is a type of thalassemia that is caused by a deficiency of the alpha globin protein. One, 2, 3, or 4 alpha globin genes may be deleted or, less commonly, contain mutations. Normally, people have 4 genes for alpha globin with 2. Jan 24, 2014 alphathalassemia is the most common human genetic disease worldwide. Jul 29, 2015 alpha thalassemia is a blood disorder that reduces the bodys production of hemoglobin. Read on to know all about its various types, symptoms and possible treatment options. Genetic testing is used to make a diagnosis of alpha thalassemia.
Alphathalassemia is one of the two forms of the life threatening blood disease known as thalassemia. Diagnosis of thalassemia disease prenatal diagnosis when both parents are known carriers of thalassemia mutation test second parent if one parent is known thalassemia trait prenatal testing with cvs or amnio if both have beta trait or both have alpha trait no consequence if one parent has alpha trait and one parent has beta trait. Heterozygotes for a single gene defect results in silent alpha thalassemia state. Alphathalassemia genetic and rare diseases information. Alpha thalassemia also occurs frequently in people from mediterranean countries, africa, the middle east, india, and central asia. Difference between sickle cell anemia and thalassemia. Normal hemoglobin consists of two alpha chains and two beta chains. Alpha thalassemia major atm is usually fatal in utero. While the excess beta globin chains are capable of forming soluble homotetramers beta4, hbh, they are. Silent carrier state is diagnosed by deduction when an apparently normal individual has a child with hemoglobin h disease or alpha thalassemia minor. Newborns need chronic transfusions to replace their red blood cells. It inhibits the production of hemoglobin and red blood cells. Alpha globin is made by four genes, two on each strand of chromosome 16.
Prevalence of thalassemia in thailand alpha thalassemia % a thalassemia 1 bangkok 3. It causes the body to make less hemoglobin than normal. Copy number variations in the form of deletions of. If amniotic fluid nonconfluent cultured cells is received. Prenatal diagnosis of deletional alpha thalassemia. Show full abstract percentage of hemoglobin barts determined by elution at ph 6. Genetic and rare diseases information center gard po box 8126, gaithersburg, md 208988126 tollfree. A person may have alpha or beta thalassemia, and symptoms depend on these types and how. Followup after confirmation of diagnosis these guidelines should be followed after a diagnosis of beta thalassemia disease has been confirmed.
Alfa thalassemia mayor gangguan pada 4 rantai globin alpha. Alpha thalassemia is a blood disorder that reduces the production of hemoglobin. Molecular diagnosis of thalassemias and hemoglobinopathies. Alpha thalassemia is a fairly common blood disorder worldwide. Best practice guidelines for molecular and haematology methods for carrier identification and prenatal diagnosis of the haemoglobinopathies external link opens in a new window traegersynodinos j, harteveld cl, old jm, et al. Thalassemia diagnosis hb gelhplc migration patterns not helpful for. It is probably the most common monogenic gene disorder in the world and is especially frequent in mediterranean countries, southeast asia, africa, the middle east and in the indian. If one parent has the cis form of alpha thalassemia trait, and the other parent is a silent carrier. As a result, haemoglobinopathies are becoming increasingly prevalent in countries where these diseases are not endemic. Alpha thalassemia alpha thalassemia is due to impaired production of the.
Alphathalassemia types, causes, diagnosis, treatment. If your web browser may not display the document correctly, rightclick over the link and select save as to save it on your computer. Abnormal pattern depends on the exact subtype see table with hemoglobin variants. In this disorder it is the defective production of hemoglobin that leads to microcytosis.
Emqn best practice guidelines for molecular and haematology methods for carrier identification and prenatal diagnosis of the. Thalassemia trait and thalassemia intermedia may require transfusion during infection or other stress. The red blood cell count rbc and the derived indices are extremely important in the diagnosis of asymptomatic. Each type of thalassaemia alpha and beta is then classified into more types, according to how severe the condition is. The diagnosis of the alphathalassemia syndromes is easily made during the newborn period by correlation of the clinical and hematologic appearance of the child with the amount of hemoglobin barts. If you need to, you can download the acrobat reader here. Thousands of infants with hb bart syndrome and hbh disease are born each year, particularly in southeast asia. Alpha thalassemia is caused by decreased synthesis of alpha globin chains. Genetic testing of partners is recommended for anyone with alpha thalassemia or alpha thalassemia trait.
The main types of thalassaemia are called alpha thalassaemia and beta thalassaemia. Laboratory diagnosis of hemoglobinopathies and thalassemia medical director, hematopathology and rbc laboratory. Alpha thalassemia is caused by reduced or absent synthesis of alpha globin chains, and beta thalas. Fetal blood transfusions are the only current treatment for supporting the fetus through pregnancy. Silent carrier 2 trait a l p h a t h a lassemia 1 trait results from deletions of 2 of the alpha gene and commonly is a subclinical anemia. Alpha thalassemia is a blood disorder that reduces the production of normal hemoglobin, the protein in red blood cells that carries oxygen to cells throughout the body there are four types of alpha thalassemia, hemoglobin bart hydrops fetalis syndrome or hb bart syndrome the more severe. Two types of alpha thalassemia can cause health problems. Because the management of severe and milder intermittent forms of. They look and feel normal but may be discovered upon routine testing hillman and ault, 2002. The form of alpha thalassemia diagnosed is dependent upon the number of working copies of the alpha. The different types of beta thalassemia mutation produce clinical and hematological phenotypes of variable severity even in betacarriers the identi. In addition, genetic testing can also identify mutations associated with rare cases of dominantly inherited.
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