Massive prolapse of the urethral mucosa following periurethral injection of calcium hydroxylapatite for stress urinary incontinence.

The injection of bulking agents into the urethral submucosa is designed to create artificial urethral cushions that can improve urethral coaptation and hence restore continence. Ideally, a urethral bulking agent should be non-immunogenic and biocompatible, leading to minimal inflammatory and fibrotic response. The authors present a case report of a granulomatous reaction leading to urethral prolapse, 3 months after the transurethral injection of calcium hydroxylapatite. To our knowledge, this is the first granulomatous reaction described after calcium hydroxylapatite injection.