What is the relationship between low ferritin (iron deficiency) levels and dysphagia (swallowing difficulty)?

The Relationship Between Iron Deficiency and Dysphagia

Iron deficiency can cause dysphagia through the development of Plummer-Vinson syndrome, which is characterized by upper esophageal stricture, cervical dysphagia, and glossitis. 1

Pathophysiological Connection

Iron deficiency affects the rapidly proliferating cells of the upper alimentary tract, which can lead to several oral and mucosal problems including:

• Upper esophageal web formation
• Esophageal strictures
• Mucosal atrophy
• Glossitis (inflammation of the tongue)
• Burning mouth syndrome

Plummer-Vinson Syndrome

This is the most well-documented connection between iron deficiency and dysphagia:

• Characterized by the triad of iron deficiency anemia, dysphagia, and upper esophageal webs
• Rare condition with an incidence less than 0.1% of patients with iron deficiency anemia 1
• More common in middle-aged women
• The dysphagia is typically painless and intermittent, progressively worsening over time

Diagnostic Approach

When evaluating a patient with dysphagia and suspected iron deficiency:

1. Assess iron status through laboratory testing:

   • Serum ferritin (primary marker) - levels <45 μg/L have 85% sensitivity for iron deficiency 2
   • Complete blood count with red cell indices
   • Transferrin saturation (<20% indicates insufficient iron) 3

2. Consider bidirectional endoscopy:

   • Especially in postmenopausal women and men with iron deficiency anemia 2
   • Can identify esophageal webs, strictures, and other structural causes of dysphagia

3. Rule out other causes of dysphagia:

   • Malignancy
   • Motility disorders
   • Neurological conditions

Treatment Approach

1. Iron Repletion:

   • Oral iron supplementation is first-line therapy for most patients 3
   • Ferrous sulfate 325 mg daily or on alternate days 4
   • In cases of severe dysphagia or poor oral absorption, consider intravenous iron 3

2. Monitor Response:

   • Dysphagia may resolve with iron repletion alone in cases of Plummer-Vinson syndrome 5
   • Follow-up should include repeat hemoglobin, ferritin, and transferrin saturation after 8-10 weeks of treatment 3
   • Target ferritin level is 50-100 μg/L 3

3. Consider Endoscopic Intervention:

   • If dysphagia persists despite iron repletion
   • Dilation of esophageal webs or strictures may be necessary

Case Evidence

A documented case report demonstrates the direct relationship between iron deficiency and dysphagia:

• A 29-year-old woman with severe iron deficiency anemia developed progressive dysphagia and a >90% upper esophageal stricture
• Iron therapy alone resolved her dysphagia and anemia
• Follow-up imaging showed reduction of stenosis from >90% to <30% 5

Clinical Pearls and Pitfalls

• Don't miss the diagnosis: Consider iron deficiency in any patient with unexplained dysphagia, especially women of reproductive age
• Look beyond anemia: Iron deficiency without anemia can still cause mucosal symptoms including dysphagia 4
• Investigate the cause: Iron deficiency is often a symptom of an underlying condition, particularly gastrointestinal blood loss 6
• Consider comorbidities: Chronic inflammatory conditions may affect ferritin levels, requiring higher cutoff values (up to 100 μg/L) for diagnosis 3

While Plummer-Vinson syndrome is rare, the evidence clearly demonstrates that iron deficiency can directly cause dysphagia, and that iron repletion can effectively resolve these symptoms in affected patients.