Transfusion Iron Chelation Therapy

As a unique electron donor and acceptor, iron is an essential element in most biological systems. However, its chemical reactivity can result in iron potentially becoming a toxin when present in excessive quantities; accordingly, total body iron must be tightly regulated. As humans have no physiological mechanism for the elimination of excess iron, body iron is controlled mainly by the degree of absorption of dietary iron from the gastrointestinal tract. The regulation of body iron, including its absorption, transport in plasma by transferrin, and storage in a number of organs as ferritin, has been reviewed elsewhere. Excessive accumulation of body iron can occur with prolonged intake of iron-containing supplements, with chronic liver disease, from some hereditary disorders of iron metabolism, from chronic ineffective erythropoiesis, and from multiple blood transfusions. This article will focus on the clinical significance of iron overload from chronic transfusion therapy and the role of iron chelation therapy to reduce excessive levels of body iron.