[Pathogenesis of anemia of chronic disease]

Anemia of chronic disease (ACD) is a mild to moderate anemia seen with many infections and inflammatory disorders. These patients have low serum iron, but high serum ferritin levels. As for the pathogenesis of ACD, previous studies have reported several abnormalities, such as insufficient EPO production, impaired growth response of erythroid progenitors to EPO, and shortened survival of erythrocytes, due to the inflammatory cytokines. However, recent analyses have clearly shown that hepcidin, of which expression is induced by inflammatory cytokines such as IL-1beta and IL-6, suppresses the expression of the iron transporter, ferroportin-1, thereby inhibiting the absorption of iron from the duodenum, the release of iron from the reticulo-endothelial system. So, the abnormal expression of hepcidin alone may be able to explain the unique iron metabolism in ACD.