- Select the CKD setting — Hemodialysis (HD) or Non-dialysis CKD / Peritoneal Dialysis (ND-CKD/PD).
- Enter the TSAT (%) — transferrin saturation from the most recent iron panel.
- Enter the ferritin (ng/mL) — serum ferritin from the same panel.
- Select whether the patient is on an ESA with Hgb below target — this matters for borderline iron stores.
- Read the color-coded decision and suggested regimen. Unit protocols vary — physician judgment is required.
All computation runs in your browser; no values are stored or transmitted.
When to Use
Use this calculator when evaluating the need for intravenous iron in adults with CKD anemia — including hemodialysis, non-dialysis CKD stages 3–5, and peritoneal dialysis patients. It applies KDIGO 2012 Anemia in CKD iron thresholds to guide the decision between iron repletion, maintenance dosing, a trial of iron, or withholding IV iron.
Appropriate population
Adults with CKD anemia (any stage including dialysis) in whom IV iron is being considered to raise hemoglobin or to reduce ESA dose. Obtain a full iron panel (TSAT and ferritin) before entering values — spot-checking only one marker is insufficient. Check iron indices after any acute illness or blood transfusion has resolved, as both can acutely shift ferritin without reflecting true stores.
When NOT to give IV iron
Withhold IV iron during active systemic infection — iron can potentiate bacterial growth, and the ferritin rise during acute phase response can falsely suggest iron overload. Also withhold during active anaphylaxis or hypersensitivity to the specific IV iron preparation. Do not use this calculator as the sole basis for prescribing — individual clinical context, local formulary, and safety monitoring requirements must be considered.
Pearls & Pitfalls
KDIGO iron thresholds at a glance
KDIGO 2012 recommends a trial of IV iron when TSAT ≤30% AND ferritin ≤500 ng/mL in HD patients. The goal is to raise Hgb or reduce ESA requirements. A ferritin >500 ng/mL is a KDIGO threshold above which routine IV iron is not recommended due to risk of iron overload — but note that ferritin is an acute-phase reactant and may be elevated by inflammation, not iron excess.
PIVOTAL trial context (HD)
The PIVOTAL trial (2019) tested proactive high-dose IV iron (400 mg every 4 weeks, targeting ferritin 400–700 ng/mL and TSAT ≥30%) vs reactive low-dose iron in HD patients and found fewer cardiovascular events, fewer ESA requirements, and no excess mortality in the high-dose arm. This supports more proactive IV iron use in HD within KDIGO-acceptable ranges, but this calculator uses conservative KDIGO 2012 thresholds — individual center protocols may reflect PIVOTAL evidence.
Pitfalls
- Ferritin is an acute-phase reactant — a high ferritin during infection or inflammation does not necessarily indicate iron overload. A concurrent low TSAT with high ferritin suggests functional iron deficiency (demand outstripping supply in an inflamed state) — treat the inflammation first.
- IV iron preparations differ in dose, frequency, and infusion requirements (iron sucrose, ferric carboxymaltose, ferric derisomaltose, low-molecular-weight iron dextran). Suggested regimens in this calculator are examples — use the preparation available at your institution per local guidelines.
- Hold IV iron during active infection — this is an absolute clinical contraindication not captured by lab values alone.
- Unit protocols vary — physician confirmation is required before prescribing.
IV Iron Decision — Repletion / Consider / Maintenance / Hold (CKD)
Enter the CKD setting, TSAT, ferritin, and ESA/Hgb status. The calculator applies KDIGO 2012 iron thresholds to recommend a decision category with target ranges, a suggested regimen example, and monitoring guidance. Unit protocols vary — physician judgment is required.
⚕ Based on KDIGO Clinical Practice Guideline for Anemia in CKD (Kidney Int Suppl. 2012;2(4):279–335). Ferritin thresholds: HD — do not routinely give IV iron if ferritin >500 ng/mL; ND-CKD/PD — ferritin threshold >200–500 ng/mL. Suggested regimens are examples — availability and unit protocols vary. Physician confirmation is required. Hold IV iron during active infection.
Next Steps
Use the result to support — not replace — clinical judgment.
- Repletion: Recheck iron indices (TSAT, ferritin) after the repletion course is complete — typically 4–6 weeks after finishing the course in ND-CKD, or at the next monthly check in HD.
- Maintenance: Check iron indices monthly during the first 3 months of a new IV iron program; every 3 months once stable. Adjust maintenance dose to keep TSAT 20–50% and ferritin 200–500 ng/mL (HD).
- Hold: Recheck iron indices in 3 months, or sooner if the clinical situation changes. If ferritin is high due to inflammation, treat the underlying cause and recheck once CRP normalizes.
- Document the iron status assessment and decision rationale at each encounter per local quality standards.
- Discuss IV iron administration logistics with the patient — HD patients typically receive iron during dialysis sessions; ND-CKD patients may require an infusion center visit.
Evidence & References
Algorithm Logic (KDIGO 2012 iron thresholds)
| TSAT / Ferritin | Setting | Decision |
|---|---|---|
| Ferritin >500 ng/mL OR TSAT >30% | Any | HOLD — avoid routine IV iron; risk of iron overload or adequate stores |
| TSAT <20% AND ferritin <200 ng/mL | ND-CKD/PD | REPLETION — absolute/functional iron deficiency |
| TSAT <20% AND ferritin <500 ng/mL | HD | REPLETION — absolute/functional iron deficiency in HD |
| TSAT 20–30% AND ferritin 200–500 ng/mL | Any | CONSIDER — give if on ESA below Hgb target or to reduce ESA dose |
| TSAT 20–50% AND ferritin 200–500 ng/mL, post-repletion | HD | MAINTENANCE — ongoing small doses to sustain iron stores |
Ferritin is an acute-phase reactant — interpret in clinical context. A high ferritin with low TSAT during infection suggests functional deficiency, not overload. Unit protocols vary — physician confirmation is required.
References
- Kidney Disease: Improving Global Outcomes (KDIGO) Anemia Work Group. KDIGO Clinical Practice Guideline for Anemia in Chronic Kidney Disease. Kidney Int Suppl. 2012;2(4):279–335.
- Macdougall IC, White C, Anker SD, et al. Intravenous iron in patients undergoing maintenance hemodialysis. N Engl J Med. 2019;380(5):447–458. (PIVOTAL trial)
