Why does iron deficiency anemia occur in chronic hemodialysis patients?
The etiology of iron deficiency in chronic hemodialysis patients is varied and can include increased iron utilization (e.g., from erythropoietin therapy), blood loss (e.g., from fistula, retention in dialyzer, hematologic testing, menses), decreased dietary intake or absorption, surgery, iron sequestration due to inflammatory process, and malignancy. The administration of exogenous erythropoietin increases red blood cell production and iron utilization. The increased iron utilization and blood losses in the hemodialysis patient may lead to absolute or functional iron deficiency. Iron deficiency is absolute when hematologic indicators of iron stores are low. Patients with functional iron deficiency do not meet laboratory criteria for absolute iron deficiency but demonstrate an increase in hemoglobin/hematocrit or a decrease in erythropoietin dosage with stable hemoglobin/hematocrit when parenteral iron is administered.
