Iron Management in Chronic Kidney Disease

Diagnosis and Definition of Iron Deficiency

The Kidney Disease: Improving Global Outcomes (KDIGO) guideline defines absolute iron deficiency as TSAT ≤20% with ferritin <100 μg/L in predialysis and peritoneal dialysis patients, or <200 μg/L in hemodialysis patients, while functional iron deficiency occurs when TSAT ≤20% despite ferritin >100 μg/L (or >200 μg/L in hemodialysis) 1, 2, 3
The American Journal of Kidney Diseases recommends target maintenance levels of TSAT ≥20% and ferritin ≥100 μg/L 1, 4

The National Kidney Foundation suggests that in non-dialysis and peritoneal dialysis CKD patients, absolute iron deficiency is defined as TSAT ≤20% AND ferritin ≤100 μg/L 1, 2
The Kidney International journal states that in hemodialysis patients, upper safety limits are avoided by not chronically maintaining TSAT >50% or ferritin >800 μg/L 4

The Kidney International journal reports that 15-72.8% of non-dialysis CKD patients have either ferritin <100 μg/L or TSAT <20% 5, 6
The American Journal of Kidney Diseases recommends measuring TSAT and ferritin at least every 3 months in hemodialysis patients to optimize erythropoiesis by adjusting IV iron dosing 4

The American Journal of Kidney Diseases warns that iron overload risk exists when TSAT chronically exceeds 50% or ferritin exceeds 800 μg/L 4
The Kidney International journal notes that iron administration may increase infection risk, particularly with non-transferrin-bound iron promoting growth of siderophilic bacteria 5