Can elevated ferritin levels be associated with Chronic Kidney Disease (CKD)?

Can Ferritin Be Elevated in Chronic Kidney Disease?

Yes, ferritin levels are frequently elevated in CKD patients independent of actual iron stores, primarily because ferritin functions as an acute-phase reactant that rises during inflammation, which is common in CKD. 1

Why Ferritin Rises in CKD

Ferritin behaves as an inflammatory marker in CKD, not just an iron storage indicator. The interpretation of ferritin in CKD patients is fundamentally different from the general population because:

• Inflammation drives ferritin elevation independent of iron stores - In hemodialysis patients, ferritin can be markedly elevated even when actual tissue iron stores are normal or low 1
• The combination of high ferritin (≥500 ng/mL) with low transferrin saturation (<25%) strongly indicates inflammation rather than iron overload - This paradoxical pattern is specifically associated with elevated inflammatory markers like C-reactive protein and IL-6 2
• Ferritin increases during acute inflammatory states and infections, making it unreliable as a sole measure of iron status 1, 3

Clinical Implications for Interpretation

You must interpret ferritin differently in CKD versus non-CKD patients:

In Hemodialysis Patients:

• Ferritin levels up to 500-700 ng/mL may still represent functional iron deficiency when inflammation is present 1
• Consider measuring C-reactive protein to assess the inflammatory contribution to elevated ferritin 1
• Transferrin saturation is more reliable than ferritin for assessing iron availability in CKD because it is less affected by inflammation 1

In Non-Dialysis CKD Patients:

• Ferritin <25 ng/mL (males) or <11 ng/mL (females) indicates true iron deficiency 1
• Elevated ferritin in the presence of low transferrin saturation suggests inflammatory iron block rather than adequate iron stores 1

Distinguishing Functional Iron Deficiency from Inflammatory Block

This is a critical clinical challenge when ferritin is 100-700 ng/mL and transferrin saturation is <20%: 1

• Functional iron deficiency: Serial ferritin levels decrease during erythropoietin therapy but remain >100 ng/mL 1
• Inflammatory iron block: Abrupt increase in ferritin associated with sudden drop in transferrin saturation 1
• Trial approach: Give weekly IV iron (50-125 mg) for 8-10 doses - if no erythropoietic response occurs, inflammatory block is most likely and further iron should be withheld until inflammation resolves 1

Association with CKD Outcomes

Higher ferritin levels correlate with CKD presence and progression:

• Men with elevated ferritin have 1.57 times higher odds of having CKD after adjusting for age and other factors 4
• Ferritin elevation reflects both iron metabolism abnormalities and the inflammatory state that accompanies CKD 5, 4
• Inflammation in CKD increases both ferritin and hepcidin independent of actual iron status, reducing iron availability 5

Key Pitfall to Avoid

Do not assume high ferritin means adequate iron stores or contraindication to iron therapy in CKD patients. The upper limit for defining iron overload is substantially higher in CKD patients with inflammation compared to those without 5. However, recent guidelines suggest maintaining ferritin <500 ng/mL in non-dialysis CKD and using proactive iron strategies in hemodialysis patients unless ferritin exceeds 700 ng/mL 1.