D2.511 - Beyond PFAS: Atypical oral manifestation of eosinophilic esophagitis in a patient with birch allergy. Case Description

Background: Eosinophilic esophagitis (EoE) is a chronic immune-mediated disease typically presenting with dysphagia and food impaction. While EoE is frequently associated with atopy, the clinical spectrum of eosinophilic gastrointestinal diseases (EGIDs) is expanding. Oral and pharyngeal involvement remains rare and is not yet included in standard diagnostic criteria.

Case Description: A 45-year-old female with a history of birch pollen allergy, seasonal rhinitis, and Pollen-Food Allergy Syndrome (PFAS) was hospitalized for recurrent, non-seasonal angioedema of the lips, soft palate, and pharynx. Symptoms included globus sensation, sore throat, and hoarseness, persisting for over a decade. Episodes lasted several days, were unresponsive to H1-antihistamines, and required systemic corticosteroids. No cutaneous or systemic symptoms were observed.

Extensive workup, including nasal endoscopy, videostroboscopy, lymphography, and food/physical provocation tests, failed to identify the etiology. Laboratory tests ruled out C1-esterase inhibitor deficiency and complement dysfunction. Results showed WBC 7.25×10³/µL (eosinophils 1.9%) and total IgE 117 IU/mL. Specific IgE confirmed sensitization to various tree/grass pollens, mites, animal dander, and PR-10-related foods (hazelnut, apple, strawberry, pear).

Gastroscopy revealed esophageal and gastric fundus polyps, Los Angeles Grade B esophagitis, and erythematous gastropathy. Histopathology confirmed ≥15 eosinophils per high-power field (HPF), leading to an EoE diagnosis. Following guideline-based treatment, the patient showed partial improvement with a significant reduction in the frequency and severity of oral edematous episodes.

Conclusion: This case suggests that eosinophilic inflammation may extend to the pharyngeal and oral mucosa. It highlights atypical EoE manifestations and emphasizes including EGIDs in the differential diagnosis of recurrent idiopathic angioedema, particularly in atopic patients.