Emphysematous cystitis: illustrative case report and review of the literature.

Emphysematous cystitis is a rare disease characterized by primary infection of the urinary bladder with gas-producing pathogens. There is a paucity of information on this entity in the English-language literature covering the last 45 years, and the clinical picture is poorly outlined. We carried out a comprehensive, retrospective review of the English-language literature from 1986 to 2006, searching for reports describing cases of emphysematous cystitis. The demographic, clinical, laboratory, imaging, and outcome characteristics of every eligible patient were excerpted. In the present report, we describe a typical case of emphysematous cystitis, followed by an analysis of the literature. Of the 53 eligible cases, most were elderly women with diabetes mellitus (62.2%). Classic symptoms of urinary tract infection were present in only 53.3% of cases. Abdominal tenderness and hematuria were noted in 65.6% and 82.3% of cases, respectively. Plain abdominal X-ray was highly sensitive (97.4%), while abdominal computerized tomography was the most sensitive and specific diagnostic tool. A complicated course attributable to emphysematous cystitis was described in 18.8% of cases. The exact mechanism contributing to the formation of gas in such cases is unknown. Various theories have been suggested, including fermentation of glucose in urine, with emphasis on disequilibrium between gas formation and clearance. Emphysematous cystitis has a highly variable presentation and course, with a considerable potential for complications. Further diagnostic imaging is highly recommended in diabetic patients with urinary tract infection who present with abdominal pain and hematuria. Knowledge of this rare entity may lead to early diagnosis and appropriate management.