S828 Adult Eosinophilic Esophagitis With Candida, HSV, and CMV Co Infections: A Systematic Review and Unique Dual HSV Case Report

Introduction: Eosinophilic esophagitis (EoE) is a chronic, immune-mediated disease defined by ≥15 eosinophils per high-power field and driven by Th2 inflammation. While Candida, herpes simplex virus (HSV), and cytomegalovirus (CMV) esophagitis are typically seen in immunocompromised hosts, emerging evidence suggests these infections may also affect immunocompetent adults with EoE due to epithelial barrier dysfunction and localized immunosuppression from swallowed steroids. To better characterize this overlap, we performed a systematic review of adult EoE cases with confirmed Candida, HSV, or CMV co-infection and present a rare case of dual HSV/EoE in an immunocompetent patient. Methods: We searched PubMed, Embase, and Web of Science (January 2015-January 2025) following PRISMA guidelines. Inclusion criteria were adult patients with histologically confirmed EoE and concurrent esophageal infection. Two reviewers independently screened studies, assessed quality using Newcastle-Ottawa and Joanna Briggs Institute tools, and extracted data on demographics, infection type, histology, treatment, and outcomes. Pooled estimates and narrative synthesis were performed. Results: Of 312 records, 13 met inclusion (12 prior cases and 1 new). Candida was most common among patients on topical steroids (16%; 95% CI 11.6-21.7%). HSV esophagitis preceded EoE in 67% of cases (95% CI 43.7-83.7%), while CMV was rare, mainly in elderly patients on budesonide. Histology revealed eosinophilic inflammation alongside fungal hyphae or viral inclusions. Our case involved a 40-year-old immunocompetent men with potassium pill impaction. Endoscopy showed severe stricture, 37-55 eos/hpf, and acute ulcerative HSV esophagitis. He improved with high-dose proton pump inhibitor and valacyclovir. Conclusion: This review highlights that infectious esophagitis and EoE are not mutually exclusive, even in immunocompetent adults. Disruption of epithelial barriers by Th2 inflammation, downregulation of junctional proteins (e.g., desmoglein-1 via Interleukin-13), and local immunosuppression from topical steroids may predispose to Candida, HSV, or CMV superinfection. In our case, pill impaction revealed underlying dual pathology. Across cases, dual-site biopsies—sampling both ulcerated and intact mucosa—were critical for diagnosis. A coordinated strategy including antimicrobials, acid suppression, cautious dilation, and delayed steroid initiation is key to optimizing outcomes and avoiding complications in dual-pathology esophagitis.