S4401 The Swiss Cheese Esophagus: A Rare Case of Intramural Pseudodiverticulosis Causing Progressive Dysphagia

Introduction: Esophageal intramural pseudodiverticulosis (EIPD) is a rare condition characterized by dilated excretory ducts of submucosal esophageal glands. It typically presents with progressive dysphagia in middle-aged patients and is frequently under-recognized. Though its pathogenesis remains unclear, associations include Candida esophagitis, eosinophilic esophagitis (EoE), and esophageal motility disorders. Case Description/Methods: A 48-year-old woman with advanced fallopian tube cancer s/p resection on chemotherapy presented with progressive solid food dysphagia. Her prior endoscopies had shown EoE and an esophageal stricture which required multiple balloon dilations. Follow-up endoscopy showed proximal stricture, concentric rings, white plaques, and numerous intramural pseudodiverticula. Brush cytology confirmed Candida esophagitis. Biopsies revealed lymphocyte-predominant esophagitis with Civatte bodies. She was treated with high-dose proton pump inhibitors and antifungals. Discussion: This case illustrates the complex interplay of infectious and inflammatory processes leading to EIPD. Our patient’s history of EoE transitioning to lymphocytic esophagitis, Candida infection, and development of EIPD supports the hypothesis that chronic mucosal inflammation and altered immunity may contribute to ductal obstruction and pseudodiverticulum formation. Proximal stenosis in EIPD is likely due to the high density of submucosal glands in the upper esophagus. EIPD should be considered in patients with recurrent dysphagia and overlapping esophagitis phenotypes, warranting thorough endoscopic evaluation. Management is generally conservative, focusing on controlling inflammation and preventing complications. Treatment may include antifungal therapy for Candida, acid suppression, endoscopic dilation for stenosis and smoking cessation. Early recognition and tailored intervention are essential to minimize chronic morbidity.