Magnetic resonance evaluation of hepatic and myocardial iron deposition in transfusion-independent thalassemia intermedia compared to regularly transfused thalassemia major patients

Abstract

Extremely diverse phenotypes exist within the homozygous and compound heterozygote states for β-thalassemia. The terms thalassemia major (TM) and intermedia (TI) lack specific molecular correlates, but encompass a wide spectrum of clinical and laboratory abnormalities [1]. At the severe end of the spectrum are patients whose clinical course is characterized by profound anemia, who present to medical attention in the first year of life, and who subsequently require regular transfusions for survival, the condition known as TM. But many patients with inheritance of two mutant beta alleles have a milder illness, with a broad range of severity including, at least in early childhood, a virtually asymptomatic state. Patients in this group who present to medical attention in later childhood and remain largely transfusion free are said to have TI [1]. The pathophysiology, clinical consequences, and treatment of iron overload in regularly transfused patients with TM have been extensively studied; however, in transfusion-independent patients with TI data remain limited. Recent advances in the assessment of organ-specific iron deposition using magnetic resonance imaging (MRI) are promising and could potentially aid understanding the pathophysiology of iron in patients with TI.