From the Guidelines
Beta thalassemia trait is a genetic condition that does not require specific treatment, and individuals with this condition should avoid unnecessary iron supplementation unless true iron deficiency is confirmed. This condition is generally asymptomatic and is characterized by mild anemia with small, pale red blood cells (microcytic hypochromic anemia) and normal or slightly elevated red blood cell count. The key laboratory findings include decreased MCV (mean corpuscular volume), decreased MCH (mean corpuscular hemoglobin), and elevated hemoglobin A2 levels on hemoglobin electrophoresis.
Some key points to consider in the management of beta thalassemia trait include:
- Avoiding unnecessary iron supplementation, as this will not improve the anemia and could lead to iron overload 1
- Confirming true iron deficiency before initiating iron supplementation
- Considering genetic counseling for family planning, as there is a 25% chance of having a child with beta thalassemia major if both parents have the trait
- Recognizing that beta thalassemia trait provides some protection against severe malaria, which explains its higher prevalence in Mediterranean, Middle Eastern, African, and Southeast Asian populations where malaria has been endemic
In terms of evaluation, if anemia does not respond to iron treatment after 4 weeks, further evaluation is recommended using other laboratory tests, including MCV, RDW, and serum ferritin concentration 1. This is particularly important in women of African, Mediterranean, or Southeast Asian ancestry, where mild anemia unresponsive to iron therapy may be due to thalassemia minor or sickle cell trait.
From the Research
Definition and Forms of Beta Thalassemia
- Beta thalassemias are a group of hereditary blood disorders characterized by anomalies in the synthesis of the beta chains of hemoglobin, resulting in variable phenotypes ranging from severe anemia to clinically asymptomatic individuals 2.
- Three main forms have been described: thalassemia major, thalassemia intermedia, and thalassemia minor.
Clinical Features and Complications
- Thalassemia major usually presents within the first two years of life with severe anemia, requiring regular red blood cell (RBC) transfusions, and can lead to complications such as iron overload, endocrine problems, and cardiac disease 2.
- Thalassemia intermedia presents later in life with moderate anemia and does not require regular transfusions, but can lead to complications such as osteoporosis, bone deformities, and increased predisposition to thrombosis 2.
- Thalassemia minor is clinically asymptomatic, but some subjects may have moderate anemia 2.
Diagnosis and Treatment
- Diagnosis of thalassemia is based on hematologic and molecular genetic testing 2.
- Treatment of thalassemia major includes regular RBC transfusions, iron chelation, and management of secondary complications of iron overload 2.
- Individuals with thalassemia intermedia may require splenectomy, folic acid supplementation, treatment of extramedullary erythropoietic masses and leg ulcers, and prevention and therapy of thromboembolic events 2.
Effect of Iron Therapy on Beta Thalassemia Trait
- Coexistence of iron deficiency anemia and beta thalassemia trait can confound the diagnosis of the latter, and iron deficiency should be identified and rectified in patients with suspicion of beta thalassemia trait 3.
- Oral iron therapy can lead to significant improvement in hemoglobin, red cell indices, and serum iron, ferritin, and HbA2 levels in patients with concomitant iron deficiency anemia and beta thalassemia trait 3.
Vitamin and Iron Studies in Beta Thalassemia
- Homozygous beta thalassemia patients may have folate deficiency, and diagnosis of folate and B12 deficiency based on serum folate, red blood cell folate, and serum B12 is vitiated in these patients 4.
- Iron overload can aggravate anemia in homozygous beta thalassemia patients, and mean hemoglobin in patients with iron overload is lower than in those without 4.