Mechanisms of hemorrhagic cystitis.

The vast majority of cases of infectious cystitis are easily treated, and most patients have no long-term complications. However, hemorrhagic cystitis is a potentially deadly complication associated with pelvic radiation therapy, chemotherapy, and stem-cell transplant therapy. The focus of current understanding, and hence therapy, is directed toward urothelial cell death. However, the primary functional ramification of inflammatory bladder disease is the loss of compliance due to muscular expansion. Recent studies on smooth muscle response in models of bladder inflammation demonstrate a process of pyroptotic cell death that potentiates further muscle hyperplasia. These findings may support alternative interventions for subjects with hemorrhagic cystitis refractive to current therapy.