EPO and chronic kidney disease: Increased risk of anemia in advanced renal disease patients could be due to the known pathogenesis of CKD mainly impaired production of erythropoietin as kidney function worsens, urinary erythropoietin losses, metabolic disturbances, and reduced red blood cells life span because of uremic environment and the possible effect of circulating uremic-induced inhibition of erythropoiesis [9, 22, 36].