Emphysematous pyelonephritis: Time for a management plan with an evidence-based approach

Introduction:
Emphysematous pyelonephritis (EPN) is a life-threatening necrotising kidney infection, but there is no consensus on the best management.

Methods:
We systematically reviewed previous articles published from 1980 to 2013 that included studies reporting on EPN, and applying the Cochrane guidelines, we conducted a meta-analysis of the results.

Results:
In all, 32 studies were included, with results for 628 patients (mean age 56.6 years, range 33.8–79.9). There were 462 women, outnumbering men by 3:1. Diabetes was present in 85% of the cases. Fevers and rigor (74.7%), pyuria (78.2%) and pain (70.4%) were the most common symptoms. Shock was associated with 54.4% of deaths while obstructive uropathy was associated with 15.1% of deaths. Computed tomography was diagnostic in all the cases. Percutaneous drainage (PCD) and medical management (MM) alone were associated with a significantly lower mortality rate than was emergency nephrectomy (EN), with an odds ratio (95% confidence interval) for PCD vs. EN of 3.13 (1.89–5.16; P < 0.001), for EN vs. MM of 2.84 (1.62–4.99; P = 0.001), and of 0.91 (0.53–1.56; P = 0.73, i.e., no difference) for PCD vs. MM. Open drainage also had a significantly lower mortality rate than EN, with a ratio of 0.12 (0.02–0.91; P < 0.04).

Conclusion:
The overall mortality rate was ≈18%; shock was associated with a high mortality rate and therefore should be managed aggressively. PCD and MM were associated with significantly higher survival rates than EN, and therefore EN should only be considered if the patient does not improve despite other treatments.