Xanthogranulomatous Pyelonephritis and Emphysematous Pyelonephritis Treatment Stabilization via Percutaneous Nephrostomy, a Retrospective Review

Xanthogranulomatous pyelonephritis (XGP) and emphysematous pyelonephritis (EPN) are both rare variants of pyelonephritis. Patients often present acutely ill and septic, and in most cases definitive therapy is nephrectomy involving high mortality rates. Some studies have suggested a role for pre-operative upper urinary tract drainage, but supporting evidence is limited.

Materials and Methods: This retrospective chart review included patients diagnosed with XGP or EPN prior to undergoing percutaneous nephrostomy (PCN) tube placement at an academic medical center from September 1, 2014 to August 31, 2024. 14 patients (8 females, 6 males) were identified using imaging criteria for EPN (7 patients) and XGP (7 patients). Average age was 47.8 years (24 – 72). To objectively quantify the data, patients’ sepsis-related sequential organ failure assessment (SOFA) score and APACHE II score were calculated before PCN, within 24 hours after PCN, seven and thirty days after PCN placement. If patient received a nephrectomy, similar scores were calculated in regards to nephrectomy timeline. Results were analyzed using a paired T-test.

Results: One patient with XGP expired within 30 days of PCN placement. Total mortality was 7.14%. Average SOFA score before PCN was 3.93, average SOFA score after seven and thirty days was 2.29 (p = 4 x 10^-5) and 1.38 (p = 0.0001), respectively. Average APACHE II score before PCN was 10.6, average APACHE II score after seven and thirty days was 7.79 (p = 0.02) and 6.23 (p = 0.002), respectively. Three nephrectomies occurred within 30 days of PCN. Average SOFA scores before PCN was 6.0, average SOFA scores before nephrectomy was 5.0 (p = 0.47). Average APACHE II score before PCN was 13.3, average APACHE II score before nephrectomy was 9.3 (p = 0.26).

Conclusion: PCN can decrease SOFA and APACHE II scores bridging acutely ill patients with XGP or EPN to nephrectomy, or can even act as definitive therapy itself. APACHE II scores indicate a 7% reduction average in mortality of patients receiving PCN prior to nephrectomy {1}. With a small sample size, a larger study to investigate effectiveness and mortality of PCN alone versus traditional treatment is warranted based upon these results.