How to manage continued iron deficiency after blood loss?

Management of Continued Iron Deficiency After Blood Loss

For continued iron deficiency after blood loss, oral iron supplementation should be administered for three months after correction of anemia to replenish iron stores, with intravenous iron therapy reserved for cases of oral iron intolerance, malabsorption, ongoing blood loss, or when rapid repletion is needed. 1

Diagnosis and Assessment

• Confirm iron deficiency using serum ferritin levels:

  • <30 μg/L: Definitive iron deficiency
  • 30-100 μg/L with transferrin saturation <20%: Possible iron deficiency, especially with inflammation

  • 100 μg/L with normal transferrin saturation: Iron deficiency unlikely 1

• Monitor hemoglobin concentration and red cell indices to track response to treatment

• Investigate underlying causes of continued iron deficiency:

  • Ongoing blood loss (gastrointestinal, menstrual)
  • Malabsorption (celiac disease, post-bariatric surgery)
  • Inadequate iron intake
  • Medication interference (e.g., proton pump inhibitors) 2

Treatment Algorithm

First-line: Oral Iron Therapy

• Dosage: 50-100 mg elemental iron once daily (e.g., ferrous sulfate 200 mg three times daily) 3, 1
• Administration: Take on an empty stomach to maximize absorption
• Duration: Continue for three months after correction of anemia to replenish iron stores 3, 1
• Optimization strategies:
  • Add ascorbic acid (vitamin C) to enhance iron absorption 3
  • Consider alternate-day dosing (60-120 mg elemental iron) for better absorption 1

Second-line: Intravenous Iron Therapy

Consider IV iron when:

• Oral iron is not tolerated
• No hemoglobin increase of at least 10 g/L after 2 weeks of oral therapy
• Malabsorption conditions exist
• Chronic inflammatory conditions are present
• Ongoing blood loss exceeds oral replacement capacity 1

IV Iron Options:

1. Ferric Carboxymaltose (Injectafer):

   • For patients ≥50 kg: 750 mg IV in two doses separated by at least 7 days (total 1,500 mg)
   • For patients <50 kg: 15 mg/kg body weight IV in two doses separated by at least 7 days
   • Alternative: 15 mg/kg up to 1,000 mg as a single dose 4

2. Iron Sucrose (Venofer):

   • 200 mg IV as slow injection over 2-5 minutes or as infusion over 15 minutes
   • Administer on 5 different occasions over a 14-day period 5

Monitoring Protocol

1. Initial response: Check hemoglobin after 2-4 weeks of treatment

   • Critical decision point: Increase in hemoglobin of at least 10 g/L after 2 weeks strongly predicts successful treatment 1

2. Ongoing monitoring:

   • Continue monitoring every 4 weeks until hemoglobin normalizes
   • Once normal, monitor hemoglobin and red cell indices every 3 months for one year, then after another year 3, 1

3. Maintenance:

   • Provide additional oral iron if hemoglobin or MCV falls below normal
   • Consider ferritin estimation in doubtful cases 3
   • Re-treatment should be initiated when serum ferritin drops below 100 μg/L or hemoglobin falls below gender-specific thresholds 1

Special Considerations

• Proton pump inhibitors: May decrease absorption of oral iron, requiring higher doses, longer duration, or switch to IV iron 2
• Ongoing blood loss: Requires identification and treatment of the underlying cause while providing iron supplementation 1
• Transfusion: Reserve for severe, symptomatic anemia with hemodynamic instability 6
• Non-response to therapy: Consider additional testing to identify other underlying causes such as:
  • Continued bleeding
  • Malabsorption
  • Concurrent deficiency of vitamin B12 or folic acid
  • Systemic disease or bone marrow pathology 1

Common Pitfalls to Avoid

• Inadequate monitoring of treatment response (check hemoglobin after 2 weeks)
• Premature discontinuation of iron therapy once hemoglobin normalizes (continue for 3 months to replenish stores)
• Overuse of blood transfusion (reserve for severe symptomatic anemia)
• Ignoring non-response to oral iron (may indicate non-compliance, malabsorption, continued bleeding)
• Failing to identify and treat the underlying cause of iron deficiency 1

By following this structured approach to managing continued iron deficiency after blood loss, you can effectively restore hemoglobin levels, replenish iron stores, and improve patient outcomes.