Dupilumab as a rescue therapy for steroid-dependent eosinophilic gastritis in a child unresponsive to elimination diet: a case report.

Background: Eosinophilic gastrointestinal diseases (EGIDs) are chronic, rare and heterogeneous disorders characterized by eosinophilic infiltration of gastrointestinal tract, resulting in gastrointestinal dysfunction. Although standard-of-care therapeutic strategies for eosinophilic esophagitis (EoE) are well-defined, limited evidence on successful treatment of eosinophilic gastrointestinal disorders beyond eosinophilic esophagitis (non-EoE EGIDs) in children is available. While dupilumab, a monoclonal antibody that inhibits interleukin (IL)-4 and IL-13 signaling, is currently approved in children with EoE, only anecdotal studies assessed its effects in children with non-EoE-EGIDs. Case presentation: This case report describes the successful use of dupilumab as a rescue therapy for a 14-year-old male with concurrent EoE and Eosinophilic Gastritis (EoG), unresponsive to dietetic approach. Despite initial responsiveness to steroid treatments, the patient experienced challenges in tapering off oral steroids without relapse. The administration of dupilumab at a dosage of 300 mg once a week led to clinical, endoscopic, and histological improvement after three months of therapy, highlighting its efficacy as a well-tolerated treatment option. Conclusions: The successful use of dupilumab as a single-therapy therapy in a steroid-dependent child, who did not respond to dietary interventions, highlights its potential in mitigating the development of steroid-related side effects. This report underscores the need for further research and clinical trials to deepen our understanding and optimize the use of dupilumab and other monoclonal antibodies in managing pediatric EGIDs, establishing a basis for the future development of treatment guidelines and protocols.