What is the appropriate management for a patient with anemia, normal Folate and Vitamin B12 levels, and low Ferritin levels?

Management of Iron Deficiency Anemia with Normal Folate and Vitamin B12 Levels

The patient with a hemoglobin of 10.2 g/dL, normal folate and vitamin B12 levels, and low ferritin of 38.44 μg/L should be treated with oral iron supplementation at a dose of 65 mg elemental iron daily. 1

Diagnosis Confirmation

• The patient's hemoglobin of 10.2 g/dL confirms anemia according to WHO criteria (Hb <130 g/L for men and <120 g/L for women) 2
• Ferritin level of 38.44 μg/L indicates iron deficiency, as values <45 μg/L are consistent with iron deficiency in the absence of inflammation 2, 3
• Normal folate (22.9) and vitamin B12 (482) levels rule out these deficiencies as contributing factors to the anemia 2

Treatment Algorithm

First-line Treatment:

• Oral iron therapy is the first-line treatment for iron deficiency anemia 2, 4
• Recommended formulation: ferrous sulfate 325 mg (providing 65 mg elemental iron) daily 1, 4
• Alternative dosing strategy: every other day dosing may improve absorption and reduce gastrointestinal side effects 4

Monitoring Response:

• Check hemoglobin after 2 weeks of therapy 2
• A good response (Hb rise ≥10 g/L within 2 weeks) confirms iron deficiency diagnosis 2
• Continue treatment for 3-6 months to replenish iron stores even after hemoglobin normalizes 4

If Poor Response:

• If no significant improvement in hemoglobin after 1 month (increase of 1-2 g/dL), consider: 5
  • Ongoing blood loss
  • Malabsorption issues
  • Need for parenteral iron therapy
  • Further investigation for underlying causes 2, 5

Special Considerations

• Take oral iron with vitamin C to enhance absorption 2
• Avoid taking iron with tea, coffee, calcium, or antacids which impair absorption 2
• Common side effects include constipation, nausea, and black stools 6
• Iron supplements should not be taken within two hours of tetracycline antibiotics 6

Underlying Cause Investigation

• For adult men and post-menopausal women, gastrointestinal blood loss is the most common cause of iron deficiency anemia and warrants investigation 2
• For pre-menopausal women, heavy menstrual bleeding is the most common cause 2, 4
• Other common causes to consider:
  • Inadequate dietary intake 4
  • Malabsorption (celiac disease, post-gastrectomy) 2, 4
  • Chronic inflammation (IBD, heart failure, chronic kidney disease) 2

Pitfalls to Avoid

• Do not assume normal ferritin excludes iron deficiency. In inflammatory states, ferritin levels up to 100 μg/L can still be consistent with iron deficiency 2
• Do not stop iron therapy once hemoglobin normalizes; continue for 3-6 months to replenish iron stores 4
• Do not miss underlying serious pathology, especially in men and post-menopausal women where GI malignancy must be excluded 2
• Do not overlook that iron deficiency without anemia can still cause symptoms like fatigue and reduced exercise tolerance 4