What is the management plan for a patient with mild iron deficiency anemia (IDA) and low normal ferritin level?

Management of Mild Iron Deficiency Anemia with Low Normal Ferritin

For a patient with mild iron deficiency anemia (hemoglobin 162 g/L) and low normal ferritin (30 μg/L), oral iron supplementation with 60-120 mg of elemental iron daily is the recommended first-line treatment, along with a thorough gastrointestinal evaluation to identify the underlying cause of iron deficiency. 1

Diagnostic Confirmation

The laboratory values indicate mild iron deficiency anemia:

• Hemoglobin: 162 g/L (mild anemia)
• Ferritin: 30 μg/L (borderline low)
• Absolute lymphocytes: 3.8 (normal)

A serum ferritin of 30 μg/L is at the lower threshold of normal, which according to current guidelines suggests iron deficiency, especially in the presence of anemia 2, 1. Recent evidence suggests that the physiologic ferritin "cutoff" should be 50 ng/mL, indicating that this patient's ferritin level is indeed suboptimal 3.

Treatment Algorithm

Step 1: Oral Iron Supplementation

• First-line therapy: Oral iron 60-120 mg elemental iron daily 1
  • Ferrous sulfate 325 mg (contains 65 mg elemental iron)
  • Alternative: Ferrous gluconate or ferrous fumarate
  • Consider alternate-day dosing to improve tolerance and absorption
  • Add vitamin C (ascorbic acid) with iron to enhance absorption
  • Avoid taking with tea, coffee, or calcium-containing foods

Step 2: Gastrointestinal Evaluation

• Essential for all patients with confirmed iron deficiency anemia 2, 1
• Upper GI endoscopy with small bowel biopsies (to rule out celiac disease)
• Colonoscopy (especially important in men and postmenopausal women)
• Testing for H. pylori and treatment if positive

Step 3: Monitoring Response

• Check hemoglobin after 3-4 weeks of treatment
  • Expected response: approximately 2 g/dL increase
  • A hemoglobin increase of at least 1.0 g/dL at day 14 predicts adequate response 1
• Recheck ferritin and hemoglobin in 3 months
  • Target ferritin level: at least 100 μg/L
  • Target hemoglobin: 11-13 g/dL

Step 4: Consider IV Iron if:

• Inadequate response to oral iron after 3 months
• Intolerance to oral iron (gastrointestinal side effects)
• Conditions impairing iron absorption (celiac disease, gastric surgery)
• Chronic inflammatory conditions (IBD, CKD, heart failure)
• Ongoing blood loss

Special Considerations

Dietary Recommendations

• Increase iron-rich foods, particularly red meat
• For vegetarians/vegans: pay special attention to iron intake
• Co-ingest vitamin C with non-heme iron sources to enhance absorption

Managing Side Effects of Oral Iron

• Common side effects: constipation, nausea, abdominal discomfort
• Strategies: take with food, reduce dosage, try different formulations

Common Pitfalls to Avoid

1. Premature discontinuation of therapy: Continue treatment until ferritin reaches at least 100 μg/L, not just until hemoglobin normalizes 1

2. Overlooking the underlying cause: Always investigate the cause of iron deficiency, even with mild anemia 2, 1

3. Accepting minor findings as the sole cause: Conditions like mild esophagitis or peptic ulcer should not be accepted as the only cause without further investigation 2

4. Inadequate follow-up: Monitor hemoglobin and iron parameters at regular intervals 1

5. Ignoring iron deficiency without anemia: Even without anemia, iron deficiency can cause symptoms like fatigue and should be treated 4

By following this structured approach, the patient's iron deficiency anemia can be effectively managed while identifying and addressing the underlying cause to prevent recurrence.