S4273 Dupilumab Increases Esophageal Diameter in 2 Patients With Refractory Fibrostenotic Eosinophilic Esophagitis

Introduction: There is limited data suggesting that dupilumab may improve esophageal diameter and distensibility in patients with refractory, fibrostenotic eosinophilic esophagitis (EoE). We present 2 cases of refractory, fibrostenotic EoE in which treatment with dupilumab resulted in global improvement and an increase in esophageal diameter. Case Description/Methods: Case 1: A 48-year-old man diagnosed with EoE 5 years ago presented for ongoing esophageal dysphagia. He continued to have daily symptoms despite fluticasone 880 mcg twice daily and omeprazole 40 mg daily. He had undergone esophageal dilation 7 times due to esophageal diameter ranging from 10 mm to 13.5 mm. The most recent endoscopy revealed an EREFS score of 5, including a 13 mm stricture that was dilated to 15 mm with dilation effect. Histopathology revealed approximately 65 eosinophils per high power field (hpf). The patient was placed on dupilumab 300 mg subcutaneous weekly monotherapy. After one year of therapy with dupilumab, the patient’s dysphagia had resolved, and endoscopy revealed an improved EREFS score of 2. No stricture was noted, and the patient’s entire esophagus was empirically dilated to 16.5 mm without dilation effect. Histopathology revealed 5 eosinophils per hpf. Case 2: A 54-year-old man with chronic dysphagia for 30 years and diagnosed with EoE 3 years ago was seen for ongoing esophageal dysphagia. He had been compliant with swallowed budesonide 1 mg twice daily in addition to omeprazole 40 mg daily. An upper endoscopy revealed an EREFS score of 7, including a 13 mm stricture in the proximal esophagus which was dilated to 13.5 mm with appropriate dilation effect. Pathology revealed 30 eosinophils per hpf. He was placed on dupilumab 300 mg subcutaneous weekly. This significantly improved his symptoms. After 5 months of treatment, a repeat upper endoscopy revealed improvement in the endoscopic findings (EREFS 4) and improvement in stricture size. His proximal stricture had improved on medication from 13.5 to 15.0 mm. A balloon dilation was performed to 16.5 mm with adequate dilation effect. Histopathology also revealed an improvement to 12 eosinophils per hpf. Discussion: These 2 cases add to the limited evidence that dupilumab may increase esophageal diameter in patients with fibrostenotic EoE. Apart from its anti-inflammatory properties, the mechanisms by which dupilumab may improve esophageal diameter are not fully understood, and more investigations are needed regarding this important attribute.