Iron Metabolism Guidelines

Normal Values and Interpretation

The American Journal of Kidney Diseases states that transferrin is normally not saturated more than 50% with iron in normal physiological conditions 1
Values below 20% suggest iron deficiency, especially when accompanied by low ferritin, according to Kidney International Supplements 2, 3

The Kidney International Supplements recommend that transferrin saturation should be interpreted along with other parameters such as hemoglobin level 4
In patients with chronic kidney disease, a transferrin saturation <20% along with ferritin <100 ng/ml suggests iron deficiency, and the therapeutic goal is to maintain transferrin saturation >20% to optimize response to erythropoiesis-stimulating agents 2, 3, 6
The National Kidney Foundation is not mentioned, however, the Praxis Medical Insights: Practical Summaries of Clinical Guidelines is, it states that in inflammatory states, ferritin may be falsely elevated while transferrin saturation may be a more reliable indicator of iron status 5

In patients with chronic kidney disease on hemodialysis, a transferrin saturation <20% may indicate iron deficiency even when ferritin is >200 ng/ml, according to Kidney International Supplements 4