Management of Iron Deficiency Anemia in a 20-Year-Old Patient
This 20-year-old patient with confirmed iron deficiency anemia (hemoglobin 9.1 g/dL, MCH 24.8, MCHC 30.4) should be started immediately on oral iron supplementation with ferrous sulfate 200 mg twice daily and continued for 3 months after correction of anemia to replenish iron stores. 1
Immediate Treatment Approach
Iron Supplementation
- Start ferrous sulfate 200 mg twice daily (most cost-effective first-line therapy) 1
- Alternative formulations if not tolerated: ferrous fumarate or ferrous gluconate 1
- Lower doses may be equally effective and better tolerated if side effects occur 1
- Continue for 3 months after hemoglobin normalizes to replenish iron stores 1
- Expected response: hemoglobin should rise by 2 g/dL after 3-4 weeks 1
Enhancing Absorption
- Consider adding ascorbic acid (250-500 mg twice daily with iron) if response is poor, though evidence for effectiveness is limited 1
Investigation Strategy for a 20-Year-Old
Age-Specific Considerations
Since this patient is under 45 years old, the investigation approach differs from older adults 1:
For patients <45 years without upper GI symptoms:
- Perform antiendomysial antibody testing (with IgA measurement) to exclude celiac disease 1
- Upper GI endoscopy with small bowel biopsy only if upper GI symptoms present 1
- Colonic investigation only if specific indications exist 1
For premenopausal women specifically:
- Iron deficiency anemia occurs in 5-10% of menstruating women 1
- Menstrual loss (especially menorrhagia), pregnancy, and breastfeeding are the usual causes 1
- Pictorial blood loss assessment charts have 80% sensitivity and specificity for detecting menorrhagia 1
Essential History Elements
- Menstrual history (quantity, duration, frequency)
- Dietary intake assessment
- NSAID use (common cause of occult GI bleeding) 2
- Previous pregnancies or breastfeeding
- Gastrointestinal symptoms (abdominal pain, change in bowel habits)
- Family history of celiac disease or inflammatory bowel disease
Monitoring and Follow-Up
Response Assessment
- Recheck hemoglobin at 3-4 weeks - should increase by 2 g/dL 1
- If inadequate response, consider: poor compliance, misdiagnosis, continued blood loss, or malabsorption 1
Long-Term Monitoring
- Monitor hemoglobin and red cell indices every 3 months for 1 year, then after another year 1
- Check ferritin if hemoglobin or MCV falls below normal 1
- Resume oral iron if indices drop 1
When to Consider Parenteral Iron
Reserve intravenous iron for specific situations: 1, 2
- Intolerance to at least two oral iron preparations
- Malabsorption (celiac disease, post-bariatric surgery)
- Ongoing significant blood loss
- Non-compliance with oral therapy
- Chronic inflammatory conditions (though less relevant in this age group)
Available IV preparations: 1
- Iron sucrose (Venofer): 200 mg over 10 minutes
- Ferric carboxymaltose (Ferinject): up to 1000 mg over 15 minutes
- Iron dextran (Cosmofer): up to 20 mg/kg over 6 hours (risk of anaphylaxis 0.6-0.7%)
Critical caveat: Resuscitation facilities must be available when administering any intravenous iron due to anaphylaxis risk 1
Common Pitfalls to Avoid
- Don't skip the 3-month continuation phase after hemoglobin normalizes - this is essential to replenish iron stores 1
- Don't perform extensive GI investigation in young menstruating women without red flags - this represents overinvestigation 1
- Don't assume oral iron failure without assessing compliance first - this is the most common cause of treatment failure 1
- Don't use faecal occult blood testing - it is insensitive and non-specific for investigating iron deficiency anemia 1
When Further Investigation is Warranted
Proceed with more extensive workup if: 1
- Hemoglobin and MCV cannot be maintained despite adequate iron supplementation
- Transfusion-dependent anemia develops
- Upper GI symptoms are present
- Age >45 years (different investigation algorithm applies)
- Red flags present: involuntary weight loss, abdominal pain, elevated inflammatory markers 3