What is the management and treatment approach for a patient with iron deficiency anemia?

Management of Iron Deficiency Anemia

All patients with iron deficiency anemia should receive oral iron supplementation (ferrous sulfate 200 mg three times daily) to correct anemia and replenish body stores, continuing for three months after hemoglobin normalization, while simultaneously investigating and treating the underlying cause. 1

Initial Treatment Approach

First-Line Iron Therapy

• Start oral ferrous sulfate 200 mg three times daily as the most cost-effective option 1
• Ferrous gluconate and ferrous fumarate are equally effective alternatives 1
• Liquid preparations may be better tolerated when tablets cause intolerance 1
• Add ascorbic acid (vitamin C) to enhance iron absorption when response is suboptimal 1
• For pregnant women, start with lower dose oral iron (30 mg/day) at first prenatal visit, increasing to 60-120 mg/day if anemia develops 1

Expected Response and Monitoring

• Hemoglobin should rise by 2 g/dL after 3-4 weeks of treatment 1
• Failure to achieve this response indicates poor compliance, misdiagnosis, continued blood loss, or malabsorption 1
• Continue iron supplementation for 3 months after anemia correction to replenish iron stores 1

When to Use Intravenous Iron

Reserve parenteral iron for specific clinical scenarios only 1:

• Intolerance to at least two different oral iron preparations 1
• Non-compliance with oral therapy 1
• Active inflammatory bowel disease with compromised absorption 1
• Portal hypertensive gastropathy with ongoing bleeding unresponsive to oral iron 1
• Celiac disease when oral iron fails to replenish stores 1
• Second and third trimesters of pregnancy 2
• Chronic kidney disease, heart failure, or cancer with chronic inflammation 2

Important caveat: Intravenous iron offers no faster hemoglobin rise than oral preparations, is expensive, painful (intramuscular), and carries risk of anaphylactic reactions 1

Diagnostic Workup While Treating

Age-Based Investigation Strategy

For patients >45 years old 1:

• Perform both upper GI endoscopy with small bowel biopsy AND colonoscopy (or barium enema) to exclude gastrointestinal malignancy 1
• This bidirectional approach is mandatory unless an obvious cause is identified with the first investigation 1

For patients <45 years old 1:

• Perform upper GI endoscopy with small bowel biopsy only if upper GI symptoms present 1
• Check antiendomysial antibodies (with IgA level to exclude IgA deficiency) to screen for celiac disease 1
• Colonoscopy only if specific indications exist (changed bowel habit, rectal bleeding) 1

For premenopausal women 1:

• Menstrual loss, menorrhagia, pregnancy, and breastfeeding account for most cases 1
• Investigation follows age-based guidelines above if symptoms warrant 1

Special Population Considerations

Inflammatory bowel disease patients 1:

• Determine whether anemia stems from inadequate intake/absorption versus blood loss 1
• Treat active inflammation effectively to enhance iron absorption 1
• Use intravenous iron when active inflammation compromises absorption 1

Portal hypertensive gastropathy 1:

• Start with oral iron supplementation initially 1
• Switch to intravenous iron if ongoing bleeding prevents response 1
• Consider nonselective β-blockers to treat portal hypertension when no other blood loss source identified 1

Celiac disease 1:

• Ensure strict adherence to gluten-free diet to improve iron absorption 1
• Use oral iron based on severity and tolerance, then intravenous if stores don't improve 1

Follow-Up Protocol

After hemoglobin normalization 1:

• Monitor hemoglobin and red cell indices every 3 months for one year 1
• Repeat monitoring after an additional year 1
• Resume oral iron if hemoglobin or MCV falls below normal (check ferritin in doubtful cases) 1
• Further investigation only necessary if hemoglobin and MCV cannot be maintained with supplementation 1

Reassuring data: Iron deficiency does not return in most patients where no cause was found after complete GI evaluation 1

When Further Investigation is Needed

Pursue additional workup if 1:

• Transfusion-dependent anemia develops 1
• Visible blood loss (melena) occurs 1
• Anemia fails to respond to appropriate iron therapy after 4 weeks 1

Advanced investigations for refractory cases 1:

• Enteroscopy to detect and treat small bowel angiodysplasia 1
• Small bowel radiology if Crohn's disease suspected 1
• Mesenteric angiography for vascular malformations in transfusion-dependent cases 1

For small-bowel angioectasias 1:

• Perform deep enteroscopy with distal attachment to improve detection 1
• Treat with argon plasma coagulation or hemostatic clips 1
• Always accompany endoscopic treatment with iron replacement 1

Common Pitfalls to Avoid

• Do not use faecal occult blood testing - it is insensitive and non-specific for IDA evaluation 1
• Do not routinely order liver function, renal function, or clotting studies unless history suggests systemic disease 1
• Exclude haematuria to rule out urinary tract tumors, though this is rare 1
• Consider co-morbidity and advanced age when deciding investigation appropriateness - discuss with patients and carers when results wouldn't influence management 1