What is the appropriate treatment for a patient with iron deficiency anemia?

Iron Deficiency Anemia: Treatment Recommendation

Based on your laboratory values showing iron deficiency (low iron saturation 13%, low serum iron 55, elevated UIBC 354, and ferritin 72.5), you should start oral ferrous sulfate 200 mg twice daily and continue for 3 months after your anemia corrects to replenish iron stores. 1

Laboratory Interpretation

Your results confirm iron deficiency:

• Iron saturation of 13% is below the diagnostic threshold of 20% 2
• Serum iron of 55 is low
• Elevated UIBC of 354 indicates depleted iron stores
• Hemoglobin of 13 g/dL represents mild anemia (below normal for men >13 g/dL, borderline for women >12 g/dL) 1
• Ferritin of 72.5 ng/mL is in the gray zone but combined with low transferrin saturation confirms iron deficiency 2

First-Line Treatment Protocol

Oral iron supplementation:

• Ferrous sulfate 200 mg twice daily (containing approximately 65 mg elemental iron per dose) 1, 3
• Alternative: Ferrous sulfate 200 mg three times daily if more aggressive repletion needed 1
• Lower doses may be equally effective and better tolerated if you experience side effects 1
• Alternative formulations (ferrous fumarate, ferrous gluconate) are equally effective if ferrous sulfate is not tolerated 1

Duration:

• Continue until hemoglobin normalizes, then continue for an additional 3 months to replenish iron stores 1

Enhance absorption:

• Consider adding ascorbic acid (vitamin C) 250-500 mg twice daily with iron if response is poor 1

Expected Response

• Hemoglobin should rise by 2 g/dL after 3-4 weeks of treatment 1
• If this does not occur, consider poor compliance, continued blood loss, malabsorption, or misdiagnosis 1

Investigation for Underlying Cause

Critical consideration based on age and sex:

If you are >45 years old (male or female):

• Upper GI endoscopy with small bowel biopsy AND colonoscopy are recommended to exclude gastrointestinal malignancy or other pathology 1
• 90% of patients should undergo bidirectional endoscopy unless an obvious cause is identified 1

If you are <45 years old:

• Premenopausal women: Menstrual blood loss is the most common cause (affects 5-10% of menstruating women) 1, 2
• Men <45 years: Should still be investigated if no obvious cause, though guidelines are less definitive 1
• Consider celiac disease screening (anti-endomysial antibody with IgA level) 1, 4
• Upper endoscopy indicated only if upper GI symptoms present 1

Other causes to evaluate:

• NSAID use (check medication history) 2
• Dietary insufficiency 4
• Malabsorption conditions (atrophic gastritis, celiac disease, post-bariatric surgery) 4, 2
• Chronic inflammatory conditions (IBD, CKD, heart failure) 2

When to Use Intravenous Iron

Parenteral iron is indicated only when: 1

• Intolerance to at least two different oral iron preparations
• Documented malabsorption (celiac disease, post-bariatric surgery, IBD)
• Ongoing blood loss that cannot be controlled
• Chronic inflammatory conditions (CKD, heart failure, IBD, cancer) 2
• Second or third trimester of pregnancy 2

Important caveat: The rise in hemoglobin with IV iron is no faster than oral iron, though initial response may appear quicker 1

Follow-Up Monitoring

Once hemoglobin normalizes:

• Monitor hemoglobin and red cell indices every 3 months for 1 year 1
• Recheck after an additional year 1
• Give additional oral iron if hemoglobin or MCV falls below normal 1
• Further investigation needed only if anemia cannot be maintained with supplementation 1

Common Pitfalls to Avoid

• Do not skip investigation for underlying cause in men or postmenopausal women—gastrointestinal malignancy must be excluded 1, 5
• Do not use faecal occult blood testing—it is insensitive and non-specific for investigating iron deficiency 1
• Do not stop iron supplementation when hemoglobin normalizes—continue for 3 additional months to replenish stores 1
• Do not assume dietary deficiency alone without proper investigation based on age and risk factors 4