How should a patient with suspected iron deficiency anemia be managed?

Management of Iron Deficiency Anemia

Based on the laboratory values (Hb 12.6, Hct 31.3, TIBC 486, iron saturation 12%, ferritin 47.9, and iron 60), this patient has iron deficiency anemia and should be treated with oral iron supplementation while investigating the underlying cause.

Diagnosis Confirmation

• The patient's laboratory values confirm iron deficiency with low iron saturation (12%) and elevated TIBC (486), despite a borderline ferritin level (47.9) 1
• Serum ferritin is the most powerful test for iron deficiency, though values up to 100 μg/L may still reflect iron deficiency in the presence of inflammation 1
• Low transferrin saturation (<20%) is a strong indicator of iron deficiency, even when ferritin may be falsely normal 1

Initial Management

• All patients with iron deficiency anemia should receive iron supplementation both to correct anemia and replenish body stores 1
• Start with oral iron therapy: ferrous sulfate 200 mg three times daily (or equivalent ferrous gluconate or ferrous fumarate) 1
• Treatment should continue for three months after correction of anemia to replenish iron stores 1
• Adding ascorbic acid (vitamin C) can enhance iron absorption when response is poor 1

Investigation of Underlying Cause

• Upper and lower GI investigations should be considered in all adult patients where iron deficiency anemia has been confirmed, unless there is a history of significant overt non-GI blood loss 1
• All patients should be screened for celiac disease (via tissue transglutaminase antibody or duodenal biopsy during endoscopy) 1
• For men and postmenopausal women, bidirectional endoscopy (upper and lower GI) should be the first-line investigation 1
• For premenopausal women, investigation should be based on clinical judgment, considering menstrual blood loss as a common cause 1
• Patients taking NSAIDs should discontinue these medications when possible, as they are common causes of IDA 1

Special Considerations

• If oral iron is not tolerated, consider:

  • Trying alternate-day dosing which may improve absorption and reduce side effects 1
  • Using liquid preparations which may be better tolerated 1
  • Switching to parenteral iron if there is intolerance to at least two oral preparations 1

• For patients with inflammatory conditions (such as IBD):

  • Oral iron may not be well absorbed during active inflammation 1
  • Intravenous iron should be considered in patients with active inflammation with compromised absorption 1

Follow-up

• Monitor hemoglobin and red cell indices after starting treatment 1
• Expect a hemoglobin rise of ≥10 g/L within a 2-week timeframe with adequate iron therapy 1
• Once normalized, monitor hemoglobin concentration and red cell indices at 3-month intervals for one year and then after a further year 1
• If hemoglobin or MCV falls below normal during follow-up, additional oral iron should be given 1
• Further investigation is only necessary if the hemoglobin and MCV cannot be maintained with iron supplementation 1

Common Pitfalls to Avoid

• Do not accept upper GI findings such as esophagitis, erosions, or peptic ulcer as the sole cause of iron deficiency without completing lower GI evaluation 1
• Remember that dual pathology (significant causes of bleeding in both upper and lower GI tracts) may occur in 10-15% of patients 1
• Do not rely on fecal occult blood testing as it is of no benefit in the investigation of iron deficiency anemia 1
• Consider that borderline ferritin levels (as in this case) may still represent iron deficiency, especially in the presence of inflammation 1