Goal Transferrin Saturation in CKD Patients

Standard Target: ≥20%

The National Kidney Foundation recommends iron should be administered to maintain transferrin saturation ≥20% in patients with hemoglobin <110 g/l, to ensure adequate iron availability for erythropoiesis 1, 2
The target transferrin saturation in CKD patients is ≥20%, with evidence supporting that maintaining levels between 30-50% may optimize anemia management and reduce ESA requirements, particularly in hemodialysis patients 1, 2

In hemodialysis patients, targeting transferrin saturation of 30-50% (versus 20-30%) allowed hemoglobin maintenance at lower ESA doses, according to the Kidney International Supplements 3
Patients with transferrin saturation ≥20% may still demonstrate absent bone marrow iron stores, indicating functional iron deficiency despite meeting the traditional threshold, as reported in the Kidney International Supplements 3

In patients below target hemoglobin or requiring high ESA doses (≥300 IU/kg/week epoetin or ≥1.5 mg/kg/week darbepoetin), consider iron supplementation even when ferritin is elevated (>800 ng/ml) if transferrin saturation remains <25%, as suggested by the Kidney International Supplements and the American Journal of Kidney Diseases 1, 2, 4, 5

Measure both transferrin saturation and ferritin together, as neither parameter alone adequately discriminates iron status, according to the American Journal of Kidney Diseases and the Kidney International Supplements [5, 6 is ignored in favor of 5]
Target transferrin saturation ≥20% as minimum threshold for all CKD patients, as recommended by the Kidney International Supplements 1, 2
Consider targeting 30-50% in hemodialysis patients to optimize ESA response and reduce dosing requirements, as reported in the Kidney International Supplements 3

Transferrin saturation reflects immediately available iron for erythropoiesis, while ferritin reflects storage iron; both must be interpreted together with hemoglobin level and ESA dose, according to the Kidney International Supplements and the American Journal of Kidney Diseases 3, 5
In inflammatory states, ferritin may be falsely elevated as an acute phase reactant, making transferrin saturation a more reliable indicator of true iron availability, as reported in the American Journal of Kidney Diseases 5