AI-generatedFerritin is normal or elevated, yet iron supply is restricted? This is possible with inflammation. Looking at ferritin alone is therefore not always enough.
Ferritin also responds to inflammation
Ferritin is both a storage parameter and an acute-phase protein. Infections or inflammatory conditions can increase its concentration. This increase need not mean that stores are optimally filled.
What role does hepcidin play?
Hepcidin regulates the passage of iron into the blood. Inflammatory processes can raise it. Less iron is then absorbed from the gut and less stored iron is released. Too little may be available for blood formation despite ferritin not appearing low.
This differs from completely depleted stores. However, both situations can coexist. An online check cannot definitively distinguish these mixed patterns.
Why transferrin saturation matters
Transferrin saturation, or TSAT, adds information about iron availability. The ASH 2026 guideline recommends using ferritin and TSAT together in adults with inflammation. Ferritin below 100 ng/ml or TSAT below 20% can indicate iron deficiency in this context. The guideline describes this as guidance; because evidence is limited, it does not set a universally binding strict threshold for every inflammatory condition.
Is normal CRP an all-clear?
Not automatically. CRP is useful, but does not fully describe all inflammatory processes. A single normal value does not make a known inflammatory condition irrelevant. The timing of results also matters.
When are specific criteria needed?
Chronic kidney disease, heart failure, cancer or inflammatory bowel disease require consideration of the underlying condition. Diagnostic criteria and treatment thresholds may differ. A general formula of “ferritin above 100 means no deficiency” would therefore be too crude.
What does this mean for treatment?
The question is not only how much iron is taken. Inflammatory activity, blood loss, the blood count and the suitability of oral treatment also matter. Please do not simply increase iron yourself when findings are unclear. Our iron status check considers these limitations and provides an overview for discussion.
