Beta-Thalassemia conditions result in decreased or absent beta globin production with resultant α chain excess. There are four commonly recognized beta thalassemia disorders and these are described in the following table:
DISORDER TYPE | PHENOTYPE | DIAGNOSES | MANAGEMENT |
β-thalassemia trait or β-thalassemia minor | Individuals usually experience no symptoms | CBC will show mild or no anemia; routine diagnostic test is Hb electrophoresis and peripheral blood smear;
pregnant women from an ethnic background at-risk for thalassemia should be screened by both CBC and a hemoglobin electrophoresis and if necessary progress to DNA studies |
Appropriate counseling for family reproductive risk |
DISORDER TYPE | PHENOTYPE | DIAGNOSES | MANAGEMENT |
β-thalassemia intermedia | Individuals may have mild anemia that may require only occasional blood transfusions, if any, and are usually symptom-free until adult life;
children who have not been treated with transfusions and who present between the ages of 2 and 6 may show developmental and growth delay |
CBC with iron studies, hemoglobin electrophoresis, DNA analysis | Due to the risk of developing iron overload, frequent monitoring for complications is recommended;
complications may include: congestive heart failure, pulmonary hypertension, diabetes mellitus, leg ulcers, hepatitis C, and insufficient thyroid secretion (hypothyroidism). blood transfusions may be required from time to time and in some cases on a long term basis similar to the major form |
DISORDER TYPE | PHENOTYPE | DIAGNOSES | MANAGEMENT |
β-thalassemia major individuals develop chronic anemia due to the inability to produce beta chains |
Symptoms may become apparent at 6-months of life;
symptoms include: paleness, irritability, growth retardation, abdominal swelling due to hepatosplenomegaly and jaundice |
CBC with iron studies, hemoglobin electrophoresis, blood smear stain for H bodies;
DNA analysis is highly recommended; iIn California, Universal Newborn Screening can pick up an elevated level of HbF (Fetal Hb which is the Hb we have before we are born and reduces rapidly just before and soon after birth ) from which a diagnosis can be suspected |
Administration of regular lifelong red blood cell transfusion is necessary and iron removal therapy;
monitoring of complications of transfusion which include iron overload symptoms and infectious complications; in special cases, bone marrow transplantation is considered |