What is the recommended treatment for microcytic, hypochromic anemia with low ferritin (iron) levels, specifically a ferritin level of severe iron deficiency?

Severe Iron Deficiency Anemia Treatment

Start oral ferrous sulfate 200 mg (65 mg elemental iron) three times daily immediately and continue for at least 3 months after hemoglobin normalizes to replenish iron stores. 1, 2, 3

Interpretation of Ferritin 2.38 μg/L

• This ferritin level indicates absent iron stores (normal cutoff <15 μg/L for absent stores, <30 μg/L for low stores), confirming severe iron deficiency as the cause of your microcytic, hypochromic anemia 3, 4
• The combination of microcytic anemia with severely low ferritin makes iron deficiency the definitive diagnosis without need for additional testing 5, 6

Immediate Treatment Protocol

Oral Iron Therapy:

• Ferrous sulfate 200 mg three times daily taken separately from meals is first-line therapy 1, 2, 3
• Add ascorbic acid (vitamin C) with each dose to enhance iron absorption 1, 2
• Alternative formulations (ferrous gluconate or ferrous fumarate) can be used if gastrointestinal side effects are intolerable 1, 3
• Continue treatment for at least 3 months after hemoglobin normalizes to fully replenish iron stores—stopping when hemoglobin normalizes is a critical pitfall that leads to relapse 2, 3

Expected Response and Monitoring

Early Response (2 weeks):

• Expect hemoglobin rise ≥10 g/L (≥1 g/dL) within 2 weeks, which confirms iron deficiency 1, 3
• Recheck CBC at 2 weeks to confirm therapeutic response 2

Intermediate Response (4 weeks):

• Expect hemoglobin increase of at least 2 g/dL within 4 weeks 2, 3
• Failure to respond after 4 weeks requires investigation for non-compliance, ongoing blood loss, malabsorption, or rare genetic disorders 3

Long-term Monitoring:

• Monitor hemoglobin and red cell indices every 3 months for 1 year, then annually 1, 2, 3

Mandatory Investigation for Underlying Cause

Gastrointestinal Blood Loss:

• Assume gastrointestinal blood loss until proven otherwise in any patient with iron deficiency 2
• Perform stool guaiac test for occult blood 2
• Men with Hb <110 g/L or non-menstruating women with Hb <100 g/L warrant fast-track GI referral to exclude malignancy 3

Menstrual History:

• Obtain detailed menstrual history if female—heavy menstrual bleeding is the most common cause in premenopausal women 3

Dietary Assessment:

• Evaluate for inadequate iron intake, particularly in vegetarian/vegan diets, eating disorders, or underweight patients 4

Malabsorption Screening:

• Screen for celiac disease if malabsorption is suspected 3

Intravenous Iron Indications

Switch to IV iron only if:

• Documented malabsorption is present 2, 3
• True intolerance to all oral formulations exists 2
• Blood losses exceed maximal oral replacement capacity 2
• Urgent treatment is needed for concomitant disease 4

Expected IV iron response: Hemoglobin increase ≥2 g/dL within 4 weeks 2, 3

Critical Pitfalls to Avoid

• Do not stop iron therapy when hemoglobin normalizes—continue for 3 months to replenish stores 2, 3
• Do not overlook combined deficiencies—iron deficiency can coexist with B12 or folate deficiency 2, 3
• Do not assume all microcytic anemia is iron deficiency—but with ferritin 2.38 μg/L, this diagnosis is certain 3
• Do not give long-term iron supplementation once ferritin normalizes—this is potentially harmful and not recommended 4

Dietary Counseling

• Integrate heme iron (meat, poultry, fish) and non-heme iron (legumes, fortified cereals) regularly into diet 4
• Consume iron with vitamin C-rich foods to enhance absorption 4
• Avoid tea, coffee, and calcium supplements within 2 hours of iron intake as they inhibit absorption 4