Emphysematous cystitis in the absence of known risk factors: an unusual clinical entity.

Emphysematous cystitis is a rare disorder that is usually associated with immunosuppression, poorly controlled diabetes mellitus, and other risk factors such as previous urinary tract infection and/or recent instrumentation of the urinary tract. The case of an 89-year-old woman with emphysematous cystitis who had no evidence of immunodeficiency or other risk factors except for advanced age is reported. A review of the literature on emphysematous cystitis in immunocompetent, nondiabetic individuals is presented.