Current possibilities of chelation therapy

Iron overload is one of the major problems in patients with hereditary and acquired anemias whose treatment uses regular packed red blood cell transfusions. The paper analyzes in detail all currently used iron store-estimating methods, such as a calculation method; determination of serum ferritin levels; measurement of liver iron concentration by both determining directly iron content in a biopsy specimen and indirectly by T2*-weighted magnetic resonance imaging (MRI (T2*)), estimation of myocardial iron by MRI (T2*). According to the current concept, the patients receiving regular packed red blood cell replacement transfusions need  adequate chelation therapy, the goal of which is to reduce toxic iron in the cell and the extracellular space and total body iron stores, which can prevent irreversible organ and tissue damage, increase survival, and improve quality of life in patients. The paper gives an algorithm for chelation therapy (to choose a chelating agent for its primary use, to modify therapy in relation to a treatment goal, and to discontinue chelation therapy). Intensive chelation therapy as continuous intravenous deferoxamine infusion or combined therapy (simultaneous or successive use of 2 different iron chelating agents) is recommended in case of severe iron overload. This literature review analyzes in detail the dosing regimen and possible combinations of different iron chelating agents, as well as criteria for evaluating their efficiency and safety.

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