THE APPROACH TO THE IRON DEFICIENT PATIENT In this attempt to forge a useful algorithm for the management of iron deficiency, it is prudent to have a discussion of the difference between overt iron deficiency, where the body

In this attempt to forge a useful algorithm for the management of iron deficiency, it is prudent to have a discussion of the difference between overt iron deficiency, where the body iron stores are depleted, and functional iron deficiency, also known as iron restricted erythropoiesis, where ample iron is present, but unavailable. Prior to the discovery of hepcidin, the hepatic synthesized iron regulatory protein, functional iron deficiency was referred to as anemia of chronic disease. We now know that hepcidin, blocks iron absorption by inactivating the only known iron exporter, ferroportin in intestinal enterocytes. Hepcidin also blocks iron release from circulating macrophages by inactivating ferroportin in these cells as well. Since hepcidin is upregulated in a huge variety of disease states, anemia of chronic disease occurs due to iron lack.