Benralizumab for anti-tumor necrosis factor-associated eosinophilic gastrointestinal disease in a child with ileal Crohn's: A case report.

Crohn's disease (CD) and eosinophilic gastrointestinal diseases (EGIDs) are distinct inflammatory entities, but eosinophilic disease may emerge as a paradoxical immune complication of anti-tumor necrosis factor therapy. We report a 12-year-old boy with terminal ileal CD who developed severe eosinophilic gastritis and ileitis, peripheral eosinophilia, and psoriasiform dermatitis during prolonged anti-TNF treatment, despite CD remission. Corticosteroids, dietary modification, and sequential biologic therapy resulted in incomplete or transient responses. Following anti-TNF withdrawal, eosinophilic disease persisted, prompting compassionate off-label treatment with benralizumab, an interleukin-5 (IL-5) receptor α-antagonist, alongside vedolizumab for CD maintenance. Benralizumab led to rapid normalization of peripheral eosinophil counts, resolution of gastrointestinal symptoms, improved food tolerance, and histologic remission at 6 months. This case illustrates persistent anti-TNF-associated immune deviation and supports targeted IL-5 receptor blockade as an effective strategy for refractory eosinophilic gastrointestinal disease while maintaining CD remission.