Iron and anemia of chronic disease.

Anemia of chronic disease (ACD) is the most frequent anemia found in hospitalized patients, often occurring in subjects suffering from chronic inflammatory disorders. The underlying diversion of iron traffic leads to a withdrawal of the metal from the sites of erythropoiesis and the circulation to the storage compartment in the reticuloendothelial system, thus resulting, at the same time, in hypoferremia and hyperferritinemia. Proinflammatory and antiinflammatory cytokines, acute-phase proteins, and radicals are prominently involved in causing these disturbances of iron homeostasis. The role of these factors, as well as the pathophysiological reasons for the development of ACD, is discussed in this review.