From the Guidelines
Yes, low ferritin and inflammation can occur simultaneously, as evidenced by the European Crohn's and Colitis Organization (ECCO) guidelines, which state that in the presence of inflammation, a serum ferritin up to 100 mg/L may still be consistent with iron deficiency 1. In patients with inflammatory bowel disease (IBD), iron deficiency anemia can coexist with inflammation, and the diagnosis of iron deficiency anemia in these patients can be challenging due to the acute phase reaction, which increases ferritin levels 1. Some key points to consider in the diagnosis and management of low ferritin and inflammation include:
- In patients without clinical, endoscopic, or biochemical evidence of active disease, serum ferritin <30 mg/L is an appropriate criterion for the diagnosis of iron deficiency anemia 1
- In the presence of inflammation, a serum ferritin up to 100 mg/L may still be consistent with iron deficiency 1
- If the serum ferritin level is between 30 and 100 mg/L, a combination of true iron deficiency and anemia of chronic disease is likely 1
- Iron supplementation is recommended in all patients with IBD, whatever their age when iron-deficiency anemia is present, and intravenous iron should be considered as first-line treatment in patients with clinically active IBD 1. The management of low ferritin and inflammation typically involves addressing the underlying inflammatory condition with appropriate medications, while simultaneously correcting iron deficiency with supplements, and laboratory testing should include complete blood count, ferritin, transferrin saturation, and inflammatory markers like C-reactive protein to properly assess both conditions 1.
From the Research
Low Ferritin and Inflammation
- Low ferritin levels can occur in the presence of inflammation, as inflammation can affect iron status and ferritin concentrations 2, 3, 4.
- Inflammation can increase ferritin levels, making it challenging to diagnose iron deficiency using serum ferritin alone 3, 4.
- Studies have shown that inflammation can increase ferritin by approximately 30-50% 3, which can lead to an underestimation of iron deficiency.
Diagnostic Challenges
- The standard threshold for iron deficiency (<30 μg/L) may not apply in inflammatory conditions, and transferrin saturation (TSAT) should also be assessed 4.
- A serum ferritin threshold of <100 μg/L or TSAT < 20% can be considered diagnostic for iron deficiency in certain inflammatory conditions, such as chronic heart failure, chronic kidney disease, and inflammatory bowel disease 4.
Mechanisms of Anemia of Inflammation
- Anemia of inflammation is characterized by a diversion of iron fluxes from the erythropoietic bone marrow to storage sites, resulting in iron-limited erythropoiesis and anemia 5.
- Proinflammatory cytokines trigger an increase in hepcidin, which restricts uptake of dietary iron and promotes sequestration of iron by ferritin within storage sites 2, 4.