Iron deficiency syndromes and iron-restricted erythropoiesis (CME).

The relationships between erythropoietin (EPO), iron, and erythropoiesis and the presence of iron-restricted erythropoiesis have important implications in anemia management. Iron-restricted erythropoiesis occurs in the presence of one or more iron deficiency syndromes: absolute iron deficiency, functional iron deficiency, and/or iron sequestration. Absolute iron deficiency is a common nutritional deficiency in women's health, pediatrics, and the elderly and is therefore an important public health problem. Functional iron deficiency occurs in patients with significant EPO-mediated erythropoiesis or therapy with erythropoiesis-stimulating agents, even when storage iron is present. Iron sequestration mediated by hepcidin is an underappreciated but common cause of iron-restricted erythropoiesis in patients with chronic inflammatory disease. The challenge for treating and laboratory-based physicians is to understand the contributory role(s) of each of these syndromes, so that the potential value of emerging and innovative pharmacologic strategies can be considered as options in patient blood management.