Understanding Elevated Ferritin: Beyond Simple Iron Overload

This landmark BMJ review fundamentally changed clinical understanding of ferritin interpretation by highlighting its dual nature as both an iron storage marker and an acute phase reactant.

Key Clinical Insights

The Problem with Standard Ranges

Traditional ferritin reference ranges (15-150 ng/mL for women) were established to detect:

• •Frank iron deficiency anemia (very low values)
• •Iron overload/hemochromatosis (very high values)

They were not designed to identify functional iron deficiency - where iron stores are technically "normal" but insufficient for optimal function.

Inflammation Masks Deficiency

Ferritin rises 2-4 fold during:

• •Acute infections
• •Chronic inflammation (elevated CRP)
• •Liver disease
• •Malignancy

A woman with true ferritin of 25 ng/mL and active inflammation might show ferritin of 75-100 ng/mL - appearing "normal" while actually deficient.

Clinical Recommendation

The authors advocate for:

1. •Always pair ferritin with CRP - essential context
2. •Use higher cutoffs when CRP elevated - consider 70 ng/mL instead of 30
3. •Consider symptoms - fatigue and hair loss at 30-50 ng/mL suggests inadequacy despite "normal" ranges
4. •Retest when inflammation resolves - true iron status may be much lower