Bladder Mass Masquerading as Eosinophilic Cystitis in a Child: When to Think Beyond Malignancy?

Eosinophilic cystitis is a rare inflammatory disease in the pediatric population with varied presentations. Diagnosis requires a high index of suspicion and cystoscopy with biopsy of the bladder mass. There are no standard treatment guidelines, however, these patients usually respond with medical management, but recurrence is a possibility. We present a case of eosinophilic cystitis in a 6-year-old boy who presented with lower urinary tract symptoms, gross hematuria, and bladder mass.