Management of iron overload: lessons from transfusion-dependent hemoglobinopathies

Before the advent of effective iron chelation, death from iron-induced cardiomyopathy and endocrine failure occurred in the second decade in patients with thalassemia major, and this experience has driven expectation of poor outcomes and caused anxiety in all disorders associated with iron loading to this day. To be clear, severe iron overload still causes significant morbidity and mortality in many parts of the world, but current understanding of iron metabolism, noninvasive monitoring of organ-specific iron loading in humans, and effective iron chelators have dramatically reduced morbidity of iron overload. Furthermore, clinical experience in hemoglobinopathies supports iron biology learned from animal studies and identifies common concepts in the biology of iron toxicity that inform the management of iron toxicity in several human disorders. The resultant significant increase in survival uncovers new complications due to much longer exposure to anemia and to iron, which must be considered in long-term therapeutic strategies. This review will discuss the management of iron toxicity in patients with hemoglobinopathies and transfusion-dependent anemias and how iron biology informs the clinical approach to treatment.