How to manage anemia with a hemoglobin of 9.6, MCV of 95.1, ferritin 153, and iron 24?

Interpretation and Management of Anemia with Hemoglobin 9.6, MCV 95.1, Ferritin 153, and Iron 24

This patient has normocytic anemia with functional iron deficiency and should be treated with intravenous iron therapy to improve hemoglobin levels and replenish iron stores.

Laboratory Interpretation

• Hemoglobin 9.6 g/dL indicates moderate anemia (WHO defines anemia as Hb <13 g/dL in men and <12 g/dL in women) 1
• MCV 95.1 fL is within normal range (normocytic) 1
• Ferritin 153 μg/L appears adequate but may be falsely elevated if inflammation is present 1
• Iron 24 μg/dL is low, suggesting functional iron deficiency despite normal ferritin 1

Diagnosis

• This pattern represents functional iron deficiency anemia (FIDA), where despite adequate ferritin levels, iron is not available for erythropoiesis 1
• Transferrin saturation (TSAT) should be calculated, as a value <20% with ferritin >100 μg/L confirms functional iron deficiency 1
• This pattern is commonly seen in anemia of chronic disease or inflammation, where hepcidin upregulation leads to iron sequestration 1

Management Approach

Step 1: Further Assessment

• Calculate transferrin saturation (TSAT) - if <20%, this confirms functional iron deficiency 1
• Check inflammatory markers (CRP, ESR) to identify underlying inflammation 1
• Consider reticulocyte count and reticulocyte hemoglobin content (CHr) - a CHr <30 pg strongly predicts response to IV iron 1

Step 2: Iron Therapy

• Intravenous iron is recommended as first-line therapy for this presentation, as oral iron is likely to be ineffective due to hepcidin-mediated blockade of iron absorption 1
• IV iron can increase hemoglobin even when ferritin is elevated (up to 500-800 μg/L) if TSAT is low (<25%) 1
• The DRIVE study demonstrated that IV iron improved hemoglobin levels in patients with elevated ferritin (500-1200 μg/L) and low TSAT (<25%) 1

Step 3: Dosing and Monitoring

• Administer IV iron according to calculated iron deficit or fixed-dose protocol (e.g., 1000 mg in 1-2 divided doses) 1
• Monitor hemoglobin response after 2-4 weeks 1
• Target hemoglobin increase of 1-2 g/dL within 4 weeks 1, 2
• Continue iron therapy for 3 months after hemoglobin normalization to replenish iron stores 1

Additional Considerations

• Investigate underlying causes of functional iron deficiency, including:

  • Chronic kidney disease 1
  • Heart failure 1
  • Inflammatory bowel disease 1
  • Chronic liver disease 1
  • Other chronic inflammatory conditions 1

• If no response to IV iron therapy within 4 weeks, consider:

  • Other causes of anemia (B12/folate deficiency, especially with normal MCV) 1
  • Bone marrow disorders 1
  • Ongoing blood loss 1, 2

Cautions and Pitfalls

• Oral iron is likely to be ineffective in functional iron deficiency and may cause gastrointestinal side effects 1
• Do not rely solely on ferritin to guide iron therapy decisions; TSAT is crucial in identifying functional iron deficiency 1
• Normal MCV does not exclude iron deficiency, especially in the context of mixed nutritional deficiencies or inflammation 1
• Ferritin is an acute phase reactant and may be elevated despite iron deficiency in inflammatory states 1
• Monitor for adverse reactions to IV iron, though modern formulations have improved safety profiles 1