The pathogenesis of the anemia of chronic renal disease is related (1) to the etiology of the renal disease, (2) to the failure of renal excretory function, and (3) to the failure of renal endocrine function. Failure of the renal excretory function leads to an increased demand for red blood cells because of shortening of the red blood cell life-span, impaired utilization of iron, decreased responsiveness to erythropoietin and increased blood loss. Failure of renal endocrine function leads to a decreased erythropoietic response to these demands because of impaired production of erythropoietin. A greater degree of anemic hypoxia is required to generate the necessary amount of erythropoietin, and an equilibrium between demand and supply is first established at anemic levels.
Erslev AJ. Anemia of Chronic Renal Disease. Arch Intern Med. 1970;126(5):774-780. doi:10.1001/archinte.1970.00310110044004