"Phenoconversion in adult patients with b-thalassemia"

Patients with clinically significant forms of β-thalassemia have been historically classified as having a β-thalassemia major or β-thalassemia intermedia phenotype, with the first primarily referring to patients who present with severe anemia during early childhood and require lifelong transfusion therapy and the latter relating to patients who present later in childhood or adolescence with mild–moderate anemia that does not necessitate immediate commitment to regular transfu- sion therapy.1 In more recent years, the terms transfusion-dependent β-thalassemia (TDT) and non-transfusion-dependent β-thalassemia (NTDT) gradually replaced the two conventional phenotypes, respec- tively, to highlight the importance of transfusion-dependence in determining the dominant pathophysiology and treatment needs.2 International management guidelines and clinical trial eligibility criteria are now clearly differentiated for TDT and NTDT.