Beta Thalassemia

Sickle cell anemia and beta thalassemia are considered the most frequent inherited blood disorders around the world. Thalassemia is a genetic disease involving the genesis of hemoglobin either chains alpha or beta. Beta thalassemia refers to defective production of the beta chain of hemoglobin. Beta thalassemia occurs when one or both Beta globin genes are either abnormal or absent. The child with thalassemia develops anemia from lower levels of hemoglobin and lacks good quality hemoglobin for oxygenation due to ineffective erythropoiesis. The gene mutation in beta thalassemia can be mild to severe, also classified as thalassemia minor or major respectively. Some patients will only need iron supplementation (non transfusion dependent thalassemia), while major cases of mutation might need regular blood transfusions for life. Hemolysis of blood is rapid, hence an overload of bilirubin is managed within the liver, reasons why some patients developed bilirubin gallstones (black pigmented stones). Patients with thalassemia experience loss of appetite, jaundice, an enlarged spleen or liver and several bone problems (osteoporosis). Iron building up in the heart leads to failure and death. A family history if thalassemia increases the chances of an individual being affected by the disease. Thalassemia affects patients with Italian, Asian, African, Middle Eastern and Greek ancestry. Whenever operating in a child with thalassemia the type of thalassemia should be ascertain as major, minor or intermedia. Also, the present of hemoglobin and iron overload must be measured.  Current management of thalassemia involves red blood cell transfusions and iron chelation. Allogeneic bone marrow transplant is the only curative option limited by the availability of matching donors and graft-versus-host disease. Gene therapy using lentiviral vectors aim to correct the mutated beta-globin gene or add back a functional copy of beta or gamma-globin. 

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