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 4-
year-old boy who presented with lower urinary tract symptoms, gross hematuria, and bladder mass.