The authors report a case of eosinophilic cystitis with a very acute course after partial cystectomy, requiring semi-urgent total cystoprostatectomy with ileal bladder replacement. The patient is completely asymptomatic ten years after the operation. This case can be classified with the pseudoneoplastic forms of interstitial cystitis occurring in patients with a history of urological surgery. The two-stage course of the disease suggests the combination of two pathophysiological mechanisms: repeated aggression to the urothelial wall responsible for an intense inflammatory reaction and allergy to suture material, accounting for the subsequent rapid development.