How to manage iron deficiency anemia with Hb of 100 and iron level of 6 umol/L?

Management of Iron Deficiency Anemia with Hb 100 g/L and Iron 6 µmol/L

Start oral iron supplementation immediately with ferrous sulfate 200 mg three times daily to correct the anemia and replenish iron stores, while simultaneously investigating the underlying cause of iron deficiency. 1

Immediate Treatment Approach

All patients with iron deficiency anemia require iron supplementation regardless of the underlying cause. 1 The treatment goals are to restore hemoglobin to normal levels and replenish depleted iron stores. 1

Oral Iron Therapy - First Line

• Ferrous sulfate 200 mg three times daily is the simplest and most cost-effective treatment. 1
• Alternative formulations include ferrous gluconate or ferrous fumarate, which are equally effective. 1
• If tablets are not tolerated, liquid preparations may be used. 1
• Consider adding ascorbic acid (vitamin C) to enhance iron absorption if response is poor. 1
• Continue iron supplementation for three months after hemoglobin normalizes to adequately replenish iron stores. 1

Expected Response to Treatment

• Hemoglobin should rise by 2 g/dL (20 g/L) after 3-4 weeks of treatment. 1
• Failure to achieve this response indicates poor compliance, misdiagnosis, continued blood loss, or malabsorption. 1
• Resolution of anemia should be achieved within six months in 80% of patients. 1

When to Use Parenteral Iron

Reserve intravenous iron only for specific situations: 1

• Intolerance to at least two different oral iron preparations
• Non-compliance with oral therapy
• Malabsorption conditions (celiac disease, inflammatory bowel disease)
• Chronic inflammatory conditions (chronic kidney disease, heart failure)
• Ongoing blood loss
• Second and third trimesters of pregnancy 2

Important caveat: Parenteral iron is painful when given intramuscularly, expensive, carries risk of anaphylactic reactions, and does not raise hemoglobin faster than oral preparations. 1

Investigation of Underlying Cause

The serum iron of 6 µmol/L (normal range typically 10-30 µmol/L) confirms iron deficiency and warrants investigation for the source of iron loss.

Age-Based Investigation Strategy

For patients over 45 years: 1

• Perform both upper GI endoscopy with small bowel biopsy AND colonoscopy (or barium enema) unless a firm cause is identified with the first investigation. 1
• This bidirectional approach is critical as 90% of patients without obvious cause should receive complete GI evaluation. 1

For patients under 45 years: 1

• Upper GI endoscopy with small bowel biopsy only if upper GI symptoms are present
• Check antiendomysial antibodies (with IgA level to exclude IgA deficiency) to screen for celiac disease 1
• Colonoscopy only if specific indications exist 1

Special Populations

Menstruating women (5-10% have iron deficiency anemia): 1

• Menstrual loss, menorrhagia, pregnancy, and breastfeeding are common causes 1
• History alone is unreliable for quantifying menstrual blood loss 1
• Consider gynecological evaluation if menorrhagia suspected

Common pitfall: Do not assume menstruation is the cause without proper evaluation, especially if symptoms are severe or refractory to treatment.

Monitoring and Follow-Up

• Monitor hemoglobin every 3 months for the first year, then again at 2 years. 1
• Check ferritin if hemoglobin or MCV falls below normal during follow-up 1
• Further investigation is only necessary if hemoglobin and MCV cannot be maintained with intermittent iron supplementation. 1
• Most patients in whom no cause is found after complete GI evaluation do not experience recurrent iron deficiency 1

When Treatment Fails

If hemoglobin does not rise appropriately after 3-4 weeks, systematically evaluate for: 1

• Poor compliance (most common)
• Misdiagnosis
• Continued blood loss
• Malabsorption

90% of non-responders should be considered for further investigation. 1