Discussion
The coexistence of PV and EoE in these two cases presents a unique clinical scenario, with only one case report in the medical literature presenting a similar association3. highlighting the complexity and interplay of autoimmune diseases. PV is an autoimmune blistering disorder primarily affecting the skin and mucous membranes, while EoE is a chronic immune-mediated esophageal condition characterized by eosinophilic infiltration and esophageal dysfunction, predominantly associated with allergic conditions1,2. Both cases underscore the necessity of a thorough and multidisciplinary diagnostic approach when dealing with patients presenting with new or unusual symptoms, particularly in those with known autoimmune conditions. In Case 1, the patient developed dysphagia and esophageal impaction, which necessitated a biopsy to distinguish between esophageal involvement by PV and EoE. In Case 2, the patient initially presented with symptoms of EoE, which were managed successfully, only to later develop PV. The diagnosis of EoE in both cases was confirmed by endoscopic findings and biopsies demonstrating significant eosinophilic infiltration. The presence of both conditions in the same patients suggests a possible shared immunopathogenic mechanism, although the exact pathophysiology remains unclear3. The simultaneous occurrence of both conditions is exceptional in the medical literature, and dysphagia in PV patients is often empirically attributed to mucosal involvement of the esophagus by PV4,5. The shared pathogenesis of PV and EoE might be linked to the involvement of desmoglein (DSG) proteins, mainly DSG-16. Our findings are consistent with a previously reported case by Gue et al. in 2017 documenting a 13-year-old boy with PV and EoE, emphasizing the possible dysregulation of DSG 1 as a common etiologic factor in both conditions3. Eosinophils play a central role in EoE and have also been implicated in the pathogenesis of PV, suggesting a shared pathogenic mechanism1,2. The significant improvement in both EoE and PV symptoms in our patient treated with dupilumab, a monoclonal antibody targeting the IL-4 receptor alpha that is FDA-approved for the treatment of EoE and used off-label for recalcitrant PV cases7–9, suggests that Th2-mediated pathways might be a common underlying mechanism in both diseases10–12.
Conclusion :
The coexistence of PV and eosinophilic esophagitis EoE in these cases highlights the complex interplay between autoimmune diseases and underscores the necessity of a thorough and multidisciplinary diagnostic approach. Our findings demonstrate that EoE should be considered in PV patients presenting with dysphagia, as it is essential not to attribute such symptoms solely to esophageal involvement by PV. The significant improvement observed in both conditions with the use of dupilumab suggests a shared Th2-mediated pathway, opening new avenues for therapeutic intervention. Further research is needed to elucidate the underlying mechanisms linking PV and EoE.