hematology and oncology
Anemia of Chronic Disease
Etiology of Anemia of Chronic Disease
The anemia of chronic disease occurs as part of a chronic inflammatory disorder, most often chronic infection, an Autoimmune Disorders (especially Three pathophysiologic mechanismshave been identified: Slightly shortened RBC survival, thought to be due to increased hemophagocytosis by macrophages, occurs in patients with inflammatory diseases. Erythropoiesis is impaired because of decreases in botherythropoietin(EPO) production and marrow responsiveness to EPO. Further, inflammatory cytokines can impair erythroid proliferation and differentiation via radical formation and/or induction of apoptosis. Iron metabolism is altered due to an increase in hepcidin, which inhibits iron absorption and recycling, leading to iron sequestration. Reticuloendothelial cells retain iron from senescent RBCs, making iron unavailable for hemoglobin (Hb) synthesis. There is thus a failure to compensate for the anemia with increased RBC production. Macrophage-derived cytokines (eg, interleukin-1-beta, interleukin-6, tumor necrosis factor-alpha,interferon-gamma) in patients with infections, inflammatory states, and cancer contribute to the decrease in EPO production and impaired iron availability by increased hepatic hepcidin synthesis. 