What are the latest guidelines for anemia management?

Latest Guidelines for Anemia Management

For iron deficiency anemia in adults, the 2021 British Society of Gastroenterology guidelines recommend oral iron supplementation (ferrous sulfate 200 mg three times daily) as first-line treatment while simultaneously conducting bidirectional GI endoscopy in at-risk populations to identify underlying causes, particularly GI malignancies. 1

Diagnostic Approach

Confirming Iron Deficiency Anemia

• Serum ferritin is the single most useful marker for diagnosing iron deficiency anemia, though transferrin saturation can help if false-normal ferritin is suspected (e.g., in inflammatory states). 1
• A hemoglobin rise ≥10 g/L within 2 weeks of iron therapy strongly suggests absolute iron deficiency, even with equivocal iron studies. 1
• Define anemia using the lower limit of normal hemoglobin for your specific laboratory reference range. 1

Initial Workup

All adults with newly diagnosed iron deficiency anemia require investigation to identify the underlying cause, as approximately one-third of men and postmenopausal women have underlying pathological abnormalities, most commonly GI malignancies. 1

The essential initial investigations include:

• Urinalysis or urine microscopy to exclude urinary blood loss 1
• Celiac disease screening (found in 3-5% of IDA cases) via serology or small bowel biopsy at gastroscopy 1
• Bidirectional endoscopy (gastroscopy with small bowel biopsy and colonoscopy) for at-risk populations 1

Risk Stratification for GI Investigation

Men and postmenopausal women with unexplained IDA should undergo urgent bidirectional GI endoscopy due to cancer risk. 1, 2

Premenopausal women under age 40-45 years can be managed more conservatively:

• Those with upper GI symptoms should have gastroscopy with small bowel biopsy 1
• Those without GI symptoms should have celiac serology (with IgA levels to exclude IgA deficiency) 1
• Colonoscopy only if specific indications exist 1

Patients over age 45 years should be investigated with full bidirectional endoscopy regardless of symptoms due to increasing cancer risk. 1

Treatment Strategy

Oral Iron Therapy (First-Line)

Ferrous sulfate 200 mg three times daily is the recommended first-line treatment, being most cost-effective, though ferrous gluconate and ferrous fumarate are equally effective alternatives. 1, 3

Key treatment principles:

• Continue iron therapy for 3 months after anemia correction to replenish iron stores 3
• Expect hemoglobin to rise by 2 g/dL after 3-4 weeks of treatment 1, 3
• Ascorbic acid enhances iron absorption and should be considered when response is poor 1
• Liquid preparations may be better tolerated when tablets cause side effects 1

Intravenous Iron Therapy (Second-Line)

Parenteral iron should only be used after failure of at least two different oral iron preparations due to intolerance or non-compliance. 1, 3

Additional indications for IV iron include:

• Malabsorption disorders 4, 5
• Severe anemia requiring rapid correction 4
• Chronic inflammatory conditions with functional iron deficiency 4, 6

Modern IV iron formulations requiring only 1-2 infusions are preferred for patient convenience. 3

Monitoring and Follow-Up

Monitor hemoglobin and red cell indices every 3 months for the first year, then annually thereafter. 3

When Treatment Fails

Failure of hemoglobin to rise by 2 g/dL after 3-4 weeks indicates:

• Poor compliance (most common) 1, 3
• Continued blood loss 1, 3
• Malabsorption 1, 3
• Misdiagnosis 1, 3

Further investigation is warranted only if hemoglobin cannot be maintained with iron supplementation or in transfusion-dependent anemia. 3

Critical Pitfalls to Avoid

• Never assume the cause of IDA without proper investigation - even obvious sources (e.g., menorrhagia, known benign lesions) may coexist with occult malignancy 1, 3
• Fecal occult blood testing is not recommended due to poor sensitivity and specificity 3
• Routine liver function tests have no diagnostic value for IDA workup unless systemic disease is suspected 3
• Do not delay investigation while treating with iron - bidirectional endoscopy should proceed urgently in at-risk populations 1
• In elderly patients, even mild anemia significantly impacts quality of life and survival, so investigate thoroughly rather than attributing it to aging 7

Special Populations

For anemia of chronic disease with functional iron deficiency, intravenous iron is generally preferred over oral therapy, particularly in patients with complex medical disorders. 4, 6

In chronic kidney disease and myelodysplastic syndromes, treat the underlying condition and consider erythropoiesis-stimulating agents in addition to iron replacement. 7