MP77-20: THE IMPACT OF LONG-TERM ANTIBIOTICS PRIOR TO NEPHRECTOMY FOR XANTHOGRANULOMATOUS PYELONEPHRITIS: MULTICENTER EVALUATION OF OPERATIVE OUTCOMES

Lillian Xie, Shlomi Tapiero, Alec R. Flores, Manuel Armas-Phan, Pengbo Jiang, Kamaljot S. Kaler, Rajiv Karani, Kaitlan D. Cobb, Roger L. Sur, Thomas Chi, Jaime Landman, Ralph V. Clayman

Introduction: Xanthogranulomatous pyelonephritis (XGP) is a destructive bacterial infection and inflammation of the renal parenchyma, typically requiring nephrectomy. We hypothesized that long-term preoperative antibiotics may facilitate a laparoscopic approach with reduced complications by shrinking the kidney and reducing inflammation.

Methods: We reviewed the records of all histologically confirmed XGP patients after nephrectomy at 3 institutions between 2005 and 2018. 61 patients were identified and stratified by antibiotic duration and surgical approach. We compared patients treated with long-term pre-operative antibiotics (=28 days of continuous treatment until surgery) to patients treated with short-term antibiotics (<28 days). Patient demographics and operative outcomes were analyzed. Complications were assigned by Clavien-Dindo classification. T-test and Chi-square tests were used to evaluate the impact of surgical approach and duration of antibiotics on perioperative outcomes.

Results: Among 61 XGP patients, 51 (84%) were female with a mean age of 50 (20-82 years) (Table 1). Median duration of preoperative antibiotics was 11 days (0-228); 24 patients (39%) received long-term antibiotics for a median duration of 64 days (28-298). Patients on long-term antibiotics were more likely to have had drainage tubes preoperatively (nephrostomy tube or perinephric drain) (71% vs. 59%, p=0.02). There was no significant difference in operative time, blood loss, transfusions, and conversion to open surgery between long-term and short-term cohorts.  However, among the 40 patients (66%) undergoing laparoscopic surgery, preoperative long-term antibiotics were associated with lower complication rate (47% vs. 89%, p=0.008) and similar length of stay (5 vs. 8 days, p=0.11).

Conclusions: Greater than four weeks of preoperative antibiotics prior to laparoscopic nephrectomy for XGP was associated with fewer postoperative complications which may be assisted by kidney drainage. Source of

Funding: N/A