To analyze the outcomes of emphysematous pyelonephritis (EPN), the impact of different treatment modalities, and to determine risk factors associated with mortality.

We retrospectively reviewed cases of EPN from 3 tertiary care institutions in Mexico. The diagnosis was confirmed with computed tomographic scan. Treatment was classified as follows: medical management (MM), minimally invasive, and surgical. Demographic, clinical, biochemical, and radiological characteristics were assessed and compared between survivors and nonsurvivors. Comparison was assessed using 1-way analysis of variance and chi-square. Univariate and multivariate logistic regression analyses were performed to determine prognostic factors. Main end point was mortality.

A total of 62 patients were included (49 women and 13 men), with a mean age of 53.9 years. The most common comorbidities were diabetes (69.3%) and hypertension (40.3%). Escherichia coli was the most common isolated microorganism (62.7%). MM was provided to 24.2%, minimally invasive treatment to 51.6%, open drainage to 19.3%, and emergency nephrectomy to 4.8%. Overall mortality was 14.5% and was similar among different treatment modalities (P = .06). Survivors were younger (P = .004), had lower creatinine (P = .002), and better estimated glomerular filtration rate (P = .007). In univariate analysis, age (P = .009), creatinine (P = .009), and need for nephrectomy (P = .03) were associated with mortality. In multivariate logistic regression analysis, creatinine (odds ratio 1.56, 95% confidence interval 1.03-2.35, P = .03) and nephrectomy (odds ratio 9.7, 95% confidence interval 1.007-93.51, P = .049) remained significant predictors of mortality.

EPN needs an aggressive MM and stepwise approach; nephrectomy should be the last resort of treatment. Creatinine level and need for nephrectomy are the strongest predictors of mortality according our analysis.