Effective use of dupilumab for eosinophilic gastritis concomitant with severe asthma

Abstract Background Eosinophilic gastrointestinal diseases (EGIDs) are chronic immune-mediated inflammatory disorders characterized by gastrointestinal symptoms and eosinophilic inflammation in specific regions of the gastrointestinal tract. EGIDs are categorized based on the location of eosinophilic inflammation. “Eosinophilic gastritis” (EoG) refers to the condition in which the stomach is involved. In patients with EoG, approved treatment options are restricted despite the high mortality associated with the condition. Therefore, drugs with various pharmacological effects are required. Dupilumab is a human monoclonal antibody directed against the interleukin (IL)-4 receptor α subunit and inhibits the signaling pathways of both IL-4 and IL-13. Additionally, dupilumab has been approved for patients with bronchial asthma, atopic dermatitis, chronic sinusitis with nasal polyposis, prurigo nodularis, chronic spontaneous urticaria, and eosinophilic esophagitis. However, real-world data on the effectiveness of dupilumab for EoG are limited. We present the case of a patient with EoG associated with severe asthma who demonstrated improvement with dupilumab administration. Case presentation: A 35-year-old woman who had been treated for asthma complained of worsening intermittent upper abdominal pain. Her dyspnea aggravated and she was admitted to our hospital for asthma exacerbation. Despite the improvement in her asthma symptoms with systemic corticosteroids, her abdominal pain persisted. Upper gastrointestinal endoscopic mucosal biopsy revealed eosinophilic cell infiltration; therefore, the patient was diagnosed with EoG. Dupilumab administration was initiated for asthma, while improvement of secondary EoG was expected. Following dupilumab administration, both EoG and asthma symptoms, disease control, laboratory findings, endoscopic findings, and pathological findings improved. As of now, no adverse events have been reported. Conclusion This case report supports that dupilumab could be an effective treatment option for EoG associated with asthma.