Thalassemia causes varying degrees of anemia, which can range from significant to life threatening. When there isnt enough hemoglobin, the bodys red blood cells dont function. The more severe the thalassemia, the less hemoglobin the body has, and the more severe the anemia may be. If desired, the diagnosis of beta thalassemia trait can be confirmed with quantitative hemoglobin studies. Fetal hemoglobin levels and morbidity in untransfused patients with.
This leads to a reduction in the number and ability of the red blood cells to carry oxygen throughout the body and can cause sufferers to feel symptoms such as fatigue. Splenomegaly can make anemia worse, and it can reduce the life of transfused red blood cells. Thalassemia genetic and rare diseases information center. Beta thalassemia trait and beta thalassemia disease. Thalassemia is an inherited blood disorder in which the body makes an abnormal form of hemoglobin. A person may have alpha or beta thalassemia, and symptoms depend on these types and how. Heterozygous individuals have mild anemia and microcytosis and are categorized as having thalassemia minor or trait, and homozygous individuals have severe. It inhibits the production of hemoglobin and red blood cells. Nov 22, 2019 thalassemia thaluhseemeuh is an inherited blood disorder that causes your body to have less hemoglobin than normal. The thalassemias have attracted worldwide interest and attention because of their high prevalence and clinical importance. Beta thalassemia is inherited as an autosomal recessive disease. The thalassemias are extremely heterogeneous in terms of their clinical severity, and their underlying pathophysiology relates directly to the extent of accumulation of excess unmatched globin chains. The impairment alters production of hemoglobin hb ridolfi et al. When there is not enough hemoglobin in the red blood cells, oxygen cannot get to all parts of the body.
Pdf abstract thalassemia s are genetic disorders inherited from a persons parents. Hemoglobin is the protein molecule in red blood cells that carries oxygen. Alpha thalassemia intermedia, or hemoglobin h disease, causes hemolytic anemia. Pathophysiology and clinical manifestations of the. This causes a shortage of red blood cells and low levels of oxygen in the bloodstream, leading to a variety of health problems. Thalassemia is an inherited disorder of autosomal recessive gene disorder caused by impaired synthesis of one or more globin chains. Sep 29, 2017 thalassemia is a genetic disease that results in abnormal globin synthesis, therefore abnormal hemoglobin formation, and microcytic anemia. Pathophysiology and treatment of patients with betathalassemia. The mutations associated with thalassemia are passed from parents to children. Jan 01, 2015 thalassemia is an inherited blood disorder that reduces the production of functional hemoglobin the protein in red blood cells that carries oxygen. Hypochromic microcytes and target cells are the main features in asymptomatic ind ividuals. Over 200 diseasecausing hbb gene mutations have been identified, most of which are point mutations. Ineffective erythropoiesis now appears to be caused by accelerated apoptosis, in turn caused primarily by deposition of.
Dec 16, 2019 beta thalassemia was the first described in 1925, by thomas cooley, a detroit pediatrician, who reported on children of italian origin who presented with severe microcytic anemia and other red cell abnormalities see image below, enlarged liver and spleen, and skull and bony abnormalities. Normal adult hemoglobin hba consists of a tetramer made up of two alphaglobin and two betaglobin subunits. Thalassemia is caused by mutations in the dna of cells that make hemoglobin the substance in red blood cells that carries oxygen throughout your body. Thalassemia is seemingly the most common genetic abnormality in the world. People with thalassemia disease are not able to make enough hemoglobin, which causes severe anemia. Laboratory diagnosis of hemoglobinopathies and thalassemia medical director, hematopathology and rbc laboratory arup laboratories assistant professor of pathology university of utah department of pathology archana m agarwal, md. The alpha globin gene is found on chromosome 16 and is duplicated, which means that each somatic cell with its pair of homologous chromosomes contains 4 copies of the alpha chain gene. Aug 23, 2018 thalassemia is a blood disorder that is caused by dna mutations in cells that are responsible for producing haemoglobin. There is a 75% or 3 in 4 chance that the baby will not have this disease. Thalassemia is often accompanied by the destruction of a large number of red blood cells and the task of removing these cells causes the spleen to enlarge. The clinical manifestations include hemolytic anemia and impaired iron handling, the severity of which depends on the degree of impairment in beta globin production. The degree of anemia in those with thalassemia intermedia is from nearly normal levels to sufficiently severe anemia to require occasional blood transfusions. Hb h disease, which causes mild to moderately severe anemia, and an enlarged spleen the organ that removes abnormal red blood cells from circulation alpha thalassemia major is the most severe type. Thalassemia is a genetic blood disorder that impacts the ability of the blood to get oxygen to the bodys organs.
A developing fetus with this type of thalassemia needs a blood transfusion while still in the womb to survive. Despite discoveries concerning the molecular abnormalities that led to the thalassemic syndromes, it still is not known how accumulation of excess unmatched. Inherited haemoglobin disorders, including thalassaemia and sicklecell disease, are the most common monogenic diseases worldwide. The reasons underlying the heterogeneity and occasional severity of the syndrome remain obscure. Alpha and beta thalassemia american family physician.
Jan 10, 2018 thalassemia is an inherited blood disorder. Betathalassemia prevalence, pathophysiology and inheritance. You inherit this genetic abnormality from your parents. Pdf pathophysiology, clinical manifestations, andcarrier. For the more severe forms of thalassaemia, modern treatment gives a good outlook, but lifelong monitoring and treatment are needed. Erythroid hyperplasia leads to medullary expansion with facial deformity and osteoporosis. The pathophysiology of alpha thalassemia is different to that of beta thalassemia. Transfusion requirement in various thalassemia forms. Iron deficiency thalassemia syndromes sideroblastic anemia transferrin deficiency 2. The word thalassemia comes originally from the greek. One way to treat anemia is to provide the body with more red blood cells to carry oxygen. Hemoglobin enables red blood cells to carry oxygen.
The presence of the entire functional a 1 gene on the leftwarddeleted chromosome yields the phenotype of a. Megaloblastic anemias folic acid b 12 deficiencies liver disease reticulocytosis normal newborn bone marrow failure syndromes drugs azt, trimethoprin sulfate. Heterozygotes are generally asymptomatic, whereas individuals who inherit thalassemia genes from each parent often have lifethreatening clinical manifestations. Pdf thalassemias are genetic disorders inherited from a persons parents. Thalassemia are a heterogeneous group of genetic disorder of hemoglobin synthesis characterized by a reduction in the synthesis of one or more of the globins chains leads to imbalanced globin chain synthesis, defective hemoglobin production causing anemia victor et al. Laboratory diagnosis of hemoglobinopathies and thalassemia. Hemoglobin e beta thalassemia is now a worldwide clinical problem. Beta thalassemia is an inherited hemoglobinopathy in which the production of one or both beta globin chains is impaired. There are different types, which vary from a mild condition with no symptoms, to a serious or lifethreatening condition. Silent carriers of alpha thalassemia and persons with alpha or beta thalassemia trait are asymp tomatic and require no treatment. Red blood cell morpho logy is altered in patients with all forms of thalassemia. Thalassemia occurs when theres an abnormality or mutation in one of the genes involved in hemoglobin production.
Thalassemia trait is commonly detected when routine peripheral blood smear and complete blood count show microcytic anemia and elevated red cell count. Klf1 mutations are relatively more common in a thalassemia endemic region and ameliorate the severity of. Such individuals are designated as having thalassemia intermedia. Hemoglobin is found in red blood cells and carries oxygen to all parts of the body. Thalassemia mechanism of disease beta thalassemia is a rare, inherited blood disorder characterized by low levels of hemoglobin, which resides in red blood cells and carries oxygen throughout the body. Thalassemia is an inherited blood disorder that can be categorized by abnormal formation of. Oxidant injury may cause hemolysis, but there is no evidence that it causes ineffective erythropoiesis. Thalassemia is due to a deficit or absent production of. Hemoglobin molecules are made of chains called alpha and beta chains that can be affected by mutations. Thalassemias are prevalent worldwide with 25000 deaths in 20. It effects as many as 1 in 30 pregnancies in china, india, and pakistan, 1 in 100 pregnancies in thailand, and 1 in pregnancies in northern europe and the united states. Beta thalassemia disease can only happen when both parents have beta thalassemia trait. If only one of your parents is a carrier for thalassemia, you may develop a form of the disease known as thalassemia minor. When both parents have beta thalassemia trait, there is a 25% or 1 in 4 chance in each pregnancy for the baby to have beta thalassemia disease.
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