The Presence of Venous Gas Does Not Affect the Prognosis in Emphysematous Cystitis.

Objective Emphysematous cystitis (EC) has a high mortality rate compared with urinary tract infection without emphysema. However, its prognostic factors have yet to be determined. The presence of venous gas is suspected to be a rare, adverse prognostic factor of EC. However, all four previously reported cases improved. We hypothesized that venous gas is not an adverse prognostic factor of EC and aimed to assess the effect of venous gas on the EC prognosis. Methods Medical records were reviewed retrospectively. Patients The patients diagnosed with EC at Yodogawa Christian Hospital between April 2004 and September 2014 were included. Results Venous gas was present in 15 of 23 patients with EC. There was no significant difference in the background or clinical presentation between patients with or without venous gas. All patients with venous gas survived without invasive measures, whereas 50% of patients without venous gas died. Conclusion There was no marked difference in the mortality rate due to EC between the patients with and without venous gas. Venous gas may be a more common and less worrying finding in EC than assumed. It does not reflect the severity of infection, and air embolisms have not been reported so far. Venous gas may not affect the prognosis. This may be due to the differences in the mechanism of venous gas production. Gas in EC may develop due to glucose fermentation and intravesical pressurization, in contrast to the necrotizing infection seen in other emphysematous infections. This is the first study to assess the effect of venous gas on EC prognosis.