Call Us: US - +1 845 478 5244 | UK - +44 20 7193 7850 | AUS - +61 2 8005 4826

allele burden and clinical correlates in polycythemia vera.


  • Evaluation for hemolytic anemia if suspected
  • Peripheral smear
  • Hemoglobin electrophoresis
  • DNA testing (prenatal diagnosis)

Thalassemia trait is commonly detected when routine peripheral blood smear and complete blood count show microcytic anemia and elevated red cell count. If desired, the diagnosis of beta thalassemia trait can be confirmed with quantitative hemoglobin studies. No intervention is needed; in women, anemia can be worsened by pregnancy.

More severe thalassemias are suspected in patients with a family history, suggestive symptoms or signs, or microcytic hemolytic anemia. If thalassemias are suspected, laboratory tests for microcytic and hemolytic anemias and quantitative hemoglobin studies are done. Serum bilirubin, iron, and ferritin levels are increased.

In alpha-thalassemias, the percentages of Hb F and Hb A2 are generally normal, and the diagnosis of single or double gene defect thalassemias may be carried out with newer genetic tests. The diagnosis often is one of exclusion of other causes of microcytic anemia.

In beta-thalassemia major, anemia is severe, often with hemoglobin ≤ 6 g/dL (≤ 60 g/L). Red blood cell count is elevated relative to hemoglobin because the cells are very microcytic. The blood smear is virtually diagnostic, with many nucleated erythroblasts; target cells; small, pale red blood cells; and punctate and diffuse basophilia.