Iron Studies Panel Interpreter
Iron Studies Panel Interpreter
Enter a full iron panel — ferritin, serum iron, TIBC and CRP — and get the pattern it represents in one reading.
Iron Studies Panel
Full panel → patternFerritin 22 µg/L, iron 42 µg/dL, TIBC 480 µg/dL, CRP 3 mg/L
What the panel computes
Ferritin threshold = 30 µg/L, or 100 µg/L when CRP > 5 mg/L
- ferritin
- iron stores; an acute-phase reactant
- TSAT
- iron supply to the erythroid marrow
- TIBC
- rises in deficiency, falls in inflammation
- CRP
- tells you which ferritin threshold applies
Worked example
Ferritin 22 µg/L, iron 42 µg/dL, TIBC 480 µg/dL, CRP 3 mg/L
Saturation = (42 ÷ 480) × 100 = 8.8%
Ferritin 22 below the 30 µg/L threshold, TIBC raised at 480
→ absolute iron deficiency
Reading the four patterns
| Pattern | Ferritin | TSAT | TIBC | CRP |
|---|---|---|---|---|
| Absolute deficiency | Low | Low | High | Normal |
| Deficiency with inflammation | Normal-looking | Low | Normal or low | Raised |
| Anaemia of inflammation | Normal or high | Low | Low | Raised |
| Iron overload | High | High | Low or normal | Normal |
Reading an iron panel as a pattern
No single iron test answers a clinical question. The panel works because its components move in characteristic combinations, and it is the combination that identifies the disorder.
In absolute deficiency, stores are empty and the liver responds by making more transferrin: ferritin falls, TIBC rises, and saturation collapses because a smaller amount of iron is spread across more binding sites. In anaemia of inflammation, hepcidin locks iron into macrophages while transferrin falls as a negative acute-phase reactant: saturation is low, but ferritin is normal or high and TIBC is low rather than high. That opposite movement of TIBC is the most useful single discriminator between the two.
Iron overload reverses the deficiency picture: saturation rises above 45%, TIBC is low or normal, and ferritin climbs. The common trap is the reverse inference — a raised ferritin with a normal saturation is far more often inflammation, alcohol, fatty liver or malignancy than haemochromatosis, and a saturation is what separates them.
The panel should be drawn as one fasting morning sample, off iron for at least 24 hours. Mixing samples drawn at different times produces a saturation that describes no real physiological moment.
Frequently asked questions
Which tests make up an iron panel?
Ferritin, serum iron and TIBC as a minimum, with transferrin saturation calculated from the last two. Adding CRP is what makes ferritin interpretable, and it is worth requesting routinely.
How do I tell iron deficiency from anaemia of inflammation?
Look at TIBC. It rises in true deficiency because the liver makes more transferrin, and falls in inflammation because transferrin is a negative acute-phase reactant. Both show a low saturation.
My ferritin is high but my saturation is normal — is that iron overload?
Usually not. Inflammation, alcohol, fatty liver disease and malignancy all raise ferritin with a normal saturation. Overload characteristically raises both.
Do I need to fast for an iron panel?
Yes where possible. Draw one morning sample after an overnight fast and at least 24 hours off iron supplements. Serum iron varies enough through the day to change the saturation materially.
Related calculators
References
- Camaschella C. Iron deficiency. Blood. 2019;133(1):30–39.
- Weiss G, Ganz T, Goodnough LT. Anemia of inflammation. Blood. 2019;133(1):40–50.
- Snook J et al. BSG guidelines for the management of iron deficiency anaemia in adults. Gut. 2021;70(11):2030–51.