Causes and Symptoms of Esophageal Eosinophilia (Eosinophilic Esophagitis)
Esophageal eosinophilia is primarily caused by an immune/antigen-mediated response, most commonly triggered by food allergens, and presents with symptoms of esophageal dysfunction including dysphagia, food impaction, and chest pain in adults, while children typically experience feeding difficulties, vomiting, and abdominal pain.
Causes of Esophageal Eosinophilia
Primary Causes:
- Food allergens: The predominant trigger for EoE, with milk and wheat being the most common culprits 1, 2
- Aeroallergens: Environmental allergens can trigger EoE in susceptible individuals 1
- Genetic factors: Polymorphisms in genes such as thymic stromal lymphopoietin protein gene increase susceptibility 1
Contributing Factors:
- Atopic conditions: EoE frequently occurs in patients with other allergic disorders (food allergy, asthma, eczema, allergic rhinitis) 1
- Environmental exposures: Early-life antibiotic exposure has been associated with increased risk 3
- Proton pump inhibitor use: May contribute to esophageal eosinophilia in some patients 1
Important Distinctions:
- PPI-responsive esophageal eosinophilia: Previously considered separate from EoE, now recognized as part of the EoE spectrum that responds to PPI therapy 1
- GERD-related eosinophilia: Reflux can cause mild esophageal eosinophilia but typically with <15 eosinophils/hpf 1
Symptoms of Esophageal Eosinophilia
In Adults:
- Dysphagia: Most common presenting symptom (solid-food difficulty swallowing) 1, 3
- Food impaction: Occurs in 33-54% of adults with EoE 1
- Chest pain: Second most common symptom in adults, may differ from GERD-related pain 1
- Upper abdominal pain 1
- Heartburn and reflux-like symptoms 1, 4
- Globus sensation (feeling of something stuck in throat) 1
In Children (Age-dependent):
- Infants and toddlers: Feeding difficulties, food refusal 1
- School-aged children: Vomiting and abdominal pain 1
- Adolescents: Dysphagia (similar to adults) 1
- Growth issues: Poor weight gain or failure to thrive in severe cases 1
Compensatory Behaviors (Often Overlooked):
- Eating slowly
- Excessive chewing
- Drinking large amounts of liquids with meals
- Avoiding certain food textures
- Cutting food into small pieces 1
Diagnostic Features
Histological Findings:
- ≥15 eosinophils per high-power field in esophageal biopsies (diagnostic threshold) 1, 3
- Additional features: eosinophilic microabscesses, surface layering of eosinophils, extracellular eosinophil granules, basal cell hyperplasia, dilated intercellular spaces, and lamina propria fibrosis 1
Endoscopic Findings:
- Linear furrows
- White plaques/exudates
- Concentric rings
- Edema
- Strictures
- Narrow-caliber esophagus 2, 5
- Note: Endoscopy may appear normal in some cases 1
Complications
Short-term:
- Acute food impaction requiring emergency endoscopy 2
- Esophageal perforation (rare, 0.8% risk during dilation procedures) 2
Long-term:
- Esophageal remodeling and fibrosis 2, 5
- Stricture formation 2
- Narrow-caliber esophagus 2
- Persistent symptoms despite treatment (91% of patients) 2, 4
Clinical Pearls and Pitfalls
- Pitfall: Relying solely on symptoms to assess disease activity—symptoms and histology are often discordant 2
- Pitfall: Missing the diagnosis in patients with <15 eosinophils/hpf who have other features of eosinophilic inflammation 1
- Pearl: Consider anxiety and depression as contributors to persistent symptoms even after histologic remission 4
- Pearl: EoE is a chronic condition requiring long-term management; spontaneous remission is uncommon 2
Understanding the causes and symptoms of esophageal eosinophilia is crucial for early diagnosis and treatment to prevent complications like esophageal strictures and remodeling that can significantly impact quality of life.