Is an Esophagogastroduodenoscopy (EGD) indicated in patients with iron deficiency?

Esophagogastroduodenoscopy (EGD) in Iron Deficiency Anemia

EGD is indicated in patients with iron deficiency anemia, particularly in men and postmenopausal women, as part of bidirectional endoscopy (EGD and colonoscopy) to identify potential gastrointestinal causes of blood loss. 1, 2

Approach to Iron Deficiency Anemia Evaluation

Initial Evaluation

• Bidirectional endoscopy (both EGD and colonoscopy) is recommended as the mainstay for gastrointestinal evaluation in:

  • Men of any age
  • Postmenopausal women
  • Patients with no other obvious source of iron deficiency 1

• For premenopausal women:

  • Individualized decision-making is needed
  • Benefits of detecting serious gastrointestinal conditions must be weighed against potential harms of endoscopy 1

Diagnostic Yield of EGD

• Studies show significant findings in asymptomatic patients with iron deficiency anemia:
  • 28.6% of patients had abnormal findings in one study, including erosive/ulcerative lesions, benign villous adenoma, and celiac disease 3
  • Another study found potential upper GI tract lesions in 49% of anemic patients and 56% of non-anemic iron-deficient patients 4

Risk Factors for Significant Findings

• Male gender (OR 7.5) 5
• Advanced age (particularly >65 years) 3, 5
• Lower mean corpuscular volume 5
• Use of NSAIDs or aspirin (36% had erosions/ulcerations) 3

Special Considerations During EGD

Celiac Disease Evaluation

• The AGA recommends initial serologic testing for celiac disease rather than routine duodenal biopsies during EGD 1
• Duodenal biopsies should be taken if:
  • Celiac serologies are positive
  • Endoscopy shows findings suggestive of celiac disease (e.g., scalloping)
  • Serologic testing was not feasible before endoscopy (e.g., open-access referral) 1

H. pylori Testing

• Noninvasive testing (e.g., stool antigen) is recommended over routine gastric biopsies 1
• Consider gastric biopsies in specific clinical scenarios such as family history of gastric cancer 1

Management After Negative Bidirectional Endoscopy

• For uncomplicated asymptomatic patients with negative bidirectional endoscopy:

  • A trial of iron supplementation is recommended over routine small bowel investigation 1
  • Monitor response to iron therapy (hemoglobin rise ≥10 g/L within 2 weeks suggests absolute iron deficiency) 2

• If iron deficiency persists despite adequate supplementation:

  • Consider small bowel evaluation with capsule endoscopy 2
  • Reconsider celiac disease even if initial serologic testing was negative 1

Pitfalls and Caveats

• Dual pathology occurs in 10-15% of patients, emphasizing the importance of complete bidirectional endoscopy 2

• In 9.5% of patients with benign upper GI lesions, synchronous colonic tumors were found 4

• Absence of gastrointestinal symptoms does not rule out significant pathology:

  • 11 of 18 patients with colonic cancer in one study were asymptomatic 4
  • Approximately 44% of asymptomatic iron-deficient patients had identifiable GI lesions in another study 6

• Red flags requiring more thorough investigation:

  • Transfusion dependence
  • Increasing age
  • Significant comorbidities
  • Ongoing weight loss or chronic unexplained diarrhea
  • Persistently elevated inflammatory markers
  • Use of anticoagulants or antiplatelet therapy 2

By following these evidence-based recommendations, clinicians can optimize the diagnostic approach to iron deficiency anemia while minimizing unnecessary procedures and maximizing detection of significant pathology.