Percutaneous drainage for non-operative management of emphysematous pyelonephritis: Clinical characteristics and predictors of success.

Emphysematous pyelonephritis (EPN) is a necrotizing renal infection that can rapidly progress without urgent intervention. The purpose of this study was to evaluate the safety and efficacy of percutaneous nephrostomy (PN) in the management of EPN, as well as the relationship of outcomes with initial classification by the Huang-Tseng classification system and other prognostic factors such as thrombocytopenia. A retrospective review of medical records revealed seven patients with EPN treated with PN. Thirty-day survival rate was 86%, with the only mortality due to an arrhythmia secondary to underlying cardiomyopathy rather than a complication from EPN or PN. A single nephrostomy procedure served as definitive treatment in 3 patients (43%). Reintervention due to recurrence of EPN symptoms was required in 4 patients (57%), all of which initially presented with Class 3 disease or higher. Two of these four patients required nephrectomy, while the other two were successfully managed with a second drainage procedure without further recurrence of symptoms. PN appears to be a safe and generally effective management option for EPN, especially in patients who are considered poor surgical candidates. PN may serve as definitive treatment in hemodynamically stable patients with lower class of disease. In patients with higher class of disease, PN may be definitive treatment in patients who lack additional risk factors such as thrombocytopenia or serve as an effective bridge to nephrectomy.