What is the management plan for a 23-year-old female with severe Iron Deficiency Anemia (IDA), hemoglobin level of 6.9 g/dL, and a poor diet?

Management of Severe Iron Deficiency Anemia (Hb 6.9 g/dL) in a 23-Year-Old Female

This patient requires immediate oral iron supplementation with ferrous sulfate 200 mg once daily, dietary counseling to increase iron and vitamin C intake, and urgent bidirectional endoscopy (gastroscopy and colonoscopy) with celiac serology to identify the underlying cause of severe anemia, as poor diet alone rarely causes hemoglobin this low in young adults. 1, 2

Immediate Management (First 24-48 Hours)

Assessment of Cardiovascular Stability

• Blood transfusion is reserved ONLY for patients with cardiovascular instability or severe symptoms (chest pain, severe dyspnea, altered mental status, hemodynamic compromise). 1, 2
• At Hb 6.9 g/dL, most young patients without cardiac disease tolerate this level due to physiological adaptation to chronic anemia. 1
• If transfusion is required, use packed red cells with a target Hb of 70-90 g/L, followed by iron replacement since transfusion alone does not replenish iron stores. 1

Initiate Iron Replacement Therapy

• Start ferrous sulfate 200 mg (65 mg elemental iron) once daily on an empty stomach. 1, 2
• Alternative formulations include ferrous fumarate 210 mg or ferrous gluconate 300 mg once daily if ferrous sulfate is unavailable. 1
• Do not delay iron therapy while awaiting investigations. 2
• Taking iron with 500 mg vitamin C enhances absorption, even if taken with food. 1
• Avoid taking iron more than once daily, as hepcidin levels remain elevated for 48 hours after dosing, blocking further absorption and increasing side effects without benefit. 1

Hospital Admission Criteria

Admission is NOT routinely required for IDA alone unless:

• Cardiovascular instability is present (requiring transfusion). 1
• Severe symptoms prevent outpatient management.
• Social circumstances prevent reliable outpatient follow-up.

Most patients with Hb 6.9 g/dL can be managed as outpatients with close monitoring. 1

Short-Term Management (First 2-4 Weeks)

Mandatory Diagnostic Workup

Despite the history of poor diet, severe IDA (Hb 6.9 g/dL) in a young woman requires investigation for gastrointestinal pathology, as dietary deficiency alone rarely causes this degree of anemia. 1, 2

Essential Investigations:

• Bidirectional endoscopy (gastroscopy AND colonoscopy) to evaluate for GI blood loss, even in the absence of GI symptoms. 1, 2
• Celiac disease screening with tissue transglutaminase (tTG) antibody at presentation, or duodenal biopsies during gastroscopy if serology unavailable. 1, 2
  • Celiac disease is present in 2-6% of patients with IDA. 1
  • If tTG is negative, duodenal biopsies are not needed unless other features suggest celiac disease. 1
• Urinalysis to exclude renal tract bleeding. 2
• Assess menstrual history quantitatively (pictorial blood loss charts have 80% sensitivity/specificity for menorrhagia). 1

Monitoring Response to Therapy

• Check hemoglobin at 2 weeks: expect a rise of ≥10 g/L if true iron deficiency. 1, 2
• Failure to achieve this rise suggests non-compliance, malabsorption, continued blood loss, concurrent B12/folate deficiency, or misdiagnosis. 1
• If oral iron is not tolerated after trying at least two different formulations, consider IV iron (not parenteral IM iron due to pain and anaphylaxis risk). 1

Long-Term Management (3-12 Months)

Duration of Iron Therapy

• Continue oral iron for 3 months AFTER hemoglobin normalizes to replenish iron stores. 1, 2
• Total treatment duration is typically 4-6 months. 1

Dietary Modifications (Non-Pharmacological)

Dietary interventions alone are insufficient to treat established severe IDA but are essential to prevent recurrence. 3, 4

Increase Iron Intake:

• Red meat provides the most bioavailable heme iron (absorbed 15-35% vs 2-20% for non-heme iron). 3, 4
• Plant-based iron sources: dark leafy greens, legumes, fortified cereals (though less bioavailable). 3, 5

Enhance Iron Absorption:

• Consume vitamin C-rich foods (citrus, tomatoes, peppers) with iron-containing meals to increase non-heme iron absorption. 1, 4
• Avoid tea, coffee, and calcium supplements within 2 hours of iron-rich meals, as they inhibit absorption. 1

Evidence for Dietary Intervention:

• Studies show dietary interventions combining increased iron AND vitamin C intake are effective for treating mild IDA, but supplementation is required for severe cases (Hb <10 g/dL). 4

Follow-Up Monitoring

• Check hemoglobin and red cell indices every 3 months for the first year, then annually. 1, 2
• If hemoglobin or MCV falls below normal during follow-up, check ferritin and resume oral iron. 1
• Further investigation is mandatory if hemoglobin cannot be maintained with iron therapy, suggesting ongoing blood loss or malabsorption. 1, 2

Prognosis

• Excellent prognosis if underlying cause is identified and treated. 1
• Most patients in whom no GI cause is found after complete investigation do not develop recurrent iron deficiency. 1
• Hemoglobin should normalize within 2-3 months with adequate iron replacement. 1
• If celiac disease is diagnosed, anemia improves with gluten-free diet alone in 80% of patients, though iron supplementation accelerates recovery. 1

What to Avoid

Medication Pitfalls:

• Do NOT prescribe modified-release iron preparations (less suitable for prescribing due to poor absorption). 1
• Do NOT dose iron more than once daily (increases side effects without improving absorption). 1
• Do NOT use intramuscular iron (painful, expensive, anaphylaxis risk, no faster than oral). 1
• Avoid switching between different oral iron salts for intolerance (not evidence-based; consider IV iron instead). 1

Dietary Pitfalls:

• Do NOT accept dietary deficiency as the sole explanation without investigation in severe IDA (Hb <10 g/dL). 1
• Do NOT rely on dietary modification alone to treat established severe IDA (supplementation is mandatory). 3, 4

Investigation Pitfalls:

• Do NOT accept upper GI findings (gastritis, esophagitis, peptic ulcer) as the sole cause without colonic evaluation, as dual pathology occurs in 10-15% of cases. 1
• Do NOT perform fecal occult blood testing (insensitive and non-specific, adds no diagnostic value). 1
• Do NOT defer investigation in premenopausal women <45 years if Hb is severely low (<10 g/dL), as GI malignancy risk increases with severity of anemia. 1

Common Side Effects to Counsel:

• Oral iron causes constipation (12%), diarrhea (8%), and nausea (11%). 1
• Taking iron with food reduces side effects but decreases absorption by 40-50%. 1
• Black stools are expected and harmless. 1