How to manage mild anaemia with abnormal iron studies suggestive of inflammation?

Management of Mild Anemia with Elevated Ferritin Suggesting Inflammation

This 74-year-old patient has anemia of chronic disease (ACD) with possible coexisting functional iron deficiency, requiring identification and treatment of the underlying inflammatory condition as the primary intervention, followed by consideration of iron supplementation if inflammation persists. 1

Interpretation of Laboratory Findings

The iron studies reveal a classic pattern of inflammation-driven anemia:

• Ferritin 533 μg/L (elevated) with low serum iron (10 μmol/L) indicates anemia of chronic disease, as ferritin >100 μg/L with transferrin saturation <20% (here 19%) is diagnostic of ACD 1
• Hemoglobin 112 g/L represents mild anemia (below the normal range of 115-155 g/L for this patient) 1
• Normal MCV (94 fL) and MCH (31 pg) indicate normocytic, normochromic anemia typical of ACD 1
• The ferritin level >150 μg/L makes absolute iron deficiency extremely unlikely, even in the presence of inflammation 1

However, the combination of ferritin between 100-800 μg/L with transferrin saturation <20% suggests possible functional iron deficiency superimposed on ACD, where iron is sequestered in macrophages and unavailable for erythropoiesis 1

Primary Management Strategy

Step 1: Identify and Treat the Underlying Inflammatory Condition

The cornerstone of management is diagnosing and treating the underlying inflammatory disease, as this is the only approach that addresses the root cause and typically normalizes hemoglobin over time. 1

Investigate for common causes in a 74-year-old:

• Chronic kidney disease: Check creatinine, eGFR, and urinalysis (already recommended) 1
• Malignancy: Age-appropriate cancer screening, particularly gastrointestinal given the anemia 1
• Chronic infections: Clinical assessment for occult infections
• Inflammatory conditions: Rheumatologic disorders, inflammatory bowel disease 1
• Liver disease: Given the comment mentions tissue damage, check liver function tests 1
• Thyroid function: Hyperthyroidism mentioned in the lab comment 1

Measure inflammatory markers (CRP, ESR) to confirm and quantify the degree of inflammation, as this is essential for proper interpretation of iron studies and guides management decisions 1

Step 2: Additional Diagnostic Workup

Based on the mild anemia and age, perform:

• Gastrointestinal investigation: Upper and lower endoscopy should be considered given the patient's age and anemia, as investigation is warranted at any level of anemia in the presence of iron abnormalities, particularly in older adults 1
• Coeliac disease screening: Serological testing, as CD is found in 3-5% of cases with iron abnormalities 1
• Vitamin B12 and folate levels: To exclude combined deficiencies that may mask microcytosis 1
• Reticulocyte count: To assess bone marrow response and help differentiate causes 1

Step 3: Iron Supplementation Considerations

Iron supplementation should be considered despite the elevated ferritin, as functional iron deficiency may be present. 1

Intravenous iron is preferred over oral iron in the setting of chronic inflammation, as:

• Oral iron absorption is impaired by inflammation-induced hepcidin elevation 2, 3, 4
• IV iron bypasses the intestinal absorption barrier and directly replenishes iron stores 1, 4
• Oral iron may exacerbate gastrointestinal symptoms if underlying GI pathology exists 1

Initiate iron supplementation when the underlying inflammatory condition is identified but anemia persists, as treating inflammation alone is rarely sufficient to normalize hemoglobin 1

Monitoring Strategy

• Recheck hemoglobin, ferritin, and transferrin saturation in 6-12 weeks after initiating treatment of the underlying condition 1
• Monitor inflammatory markers (CRP/ESR) to assess response to treatment of the underlying disease 1
• Long-term surveillance every 6-12 months is warranted, as recurrence of anemia occurs in >50% of patients within one year and often indicates ongoing inflammation 1

Critical Pitfalls to Avoid

• Do not assume iron deficiency is absent based solely on elevated ferritin in the setting of inflammation—ferritin between 30-100 μg/L suggests combined iron deficiency and ACD, but even at 533 μg/L, functional iron deficiency may exist 1
• Do not initiate iron supplementation without investigating the underlying cause of inflammation, as this addresses symptoms rather than the disease process 1
• Do not use oral iron as first-line therapy in chronic inflammatory conditions, as absorption is impaired and efficacy is limited 2, 4
• Do not overlook gastrointestinal investigation in a 74-year-old with anemia, regardless of the ferritin level, as occult malignancy must be excluded 1