From the Guidelines
Thalassemia diagnosis should be approached with a combination of blood tests, including a complete blood count (CBC), hemoglobin electrophoresis, peripheral blood smear, and iron studies, as well as genetic testing to identify specific mutations in the alpha or beta globin genes, as recommended by the most recent guidelines 1.
Initial Screening
The initial screening for thalassemia typically includes a CBC to check for anemia, reduced hemoglobin levels, and microcytic (small) red blood cells. This is based on the principle that abnormalities in two or more cell lines should be evaluated carefully and likely warrant discussion with a hematologist 1.
Additional Tests
Additional tests include:
- Hemoglobin electrophoresis to separate different types of hemoglobin and identify abnormal forms characteristic of thalassemia
- Peripheral blood smear to examine red blood cell shape and size
- Iron studies to rule out iron deficiency anemia which can present similarly
Definitive Diagnosis
For definitive diagnosis, genetic testing may be performed to identify specific mutations in the alpha or beta globin genes. Family members of affected individuals should also consider screening since thalassemia is hereditary.
Recent Guidelines
Recent guidelines recommend a combination of tests, including plasma iron, transferrin, transferrin saturation, ferritin, CRP, hepcidin, and evaluation of red blood cell morphology, for the investigation of suspected deficiency and overload 1.
Severity and Treatment
These tests help determine the type and severity of thalassemia, which guides treatment decisions ranging from observation for mild cases to regular blood transfusions and iron chelation therapy for more severe forms. Early diagnosis is crucial as it allows for proper management and prevention of complications like iron overload.
From the Research
Thalassemia Blood Tests
- Thalassemia is a group of autosomal recessive hemoglobinopathies affecting the production of normal alpha- or beta-globin chains that comprise hemoglobin 2
- Thalassemia should be suspected in patients with microcytic anemia and normal or elevated ferritin levels 2
- Hemoglobin electrophoresis may reveal common characteristics of different thalassemia subtypes, but genetic testing is required to confirm the diagnosis 2, 3
- Definitive diagnosis of thalassemia and hemoglobinopathies requires a comprehensive workup from complete blood count, hemoglobin analysis, and molecular studies to identify mutations of globin genes 3
Diagnosis and Screening
- Serum ferritin measurement and noninvasive imaging techniques are available to diagnose iron overload, quantify its extent in different organs, and monitor clinical response to therapy 4
- Thalassemic disorders lie on a phenotypic spectrum of clinical severity that depends on the severity of the globin gene mutation and coinheritance of other genetic determinants 4
- Genetic counseling and screening in high-risk populations can assist in reducing the prevalence of thalassemia 2