Optimal duration of preoperative antibiotic treatment prior to ureteroscopic lithotripsy to prevent postoperative systemic inflammatory response syndrome in patients presenting with urolithiasis-induced obstructive acute pyelonephritis

PURPOSE: There is no consensus on the optimal duration of preoperative antibiotic treatment prior to ureteroscopic lithotripsy in patients presenting with urolithiasis-induced obstructive acute pyelonephritis (APN). We aimed to identify surgeon-modifiable, preoperative risk factors associated with postoperative systemic inflammatory response syndrome (SIRS) in these patients. MATERIALS AND METHODS: This multicenter retrospective study evaluated 115 patients who presented with urolithiasis-induced obstructive APN between January 2008 and December 2019. All patients were administered intravenous third-generation cephalosporin until culture sensitivity confirmation or until ureteroscopic lithotripsy. Data were collected for age, sex, diabetes mellitus, performance status, stone features, hydronephrosis grade, preoperative renal collecting system drainage, laboratory data, operative time, and duration of preoperative antibiotic treatment. Sensitivity analysis using Youden's index and logistic regression analysis were used to assess risk factors of postoperative SIRS. RESULTS: Postoperative SIRS was identified in 32 (27.8%) patients. The incidence of postoperative SIRS was higher in patients who received preoperative antibiotic treatment for fewer than 14 days (38.8% vs. 12.5%; p=0.001). Backward variable selection logistic regression analysis revealed maximal stone diameter ≥15 mm, duration of preoperative antibiotic treatment <14 days, and preoperative C-reactive protein (CRP) level ≥6.0 mg/L to be associated with higher risk of postoperative SIRS. CONCLUSIONS: Patients with urolithiasis-induced obstructive APN planned for ureteroscopic lithotripsy should be administered at least 14 days of preoperative antibiotic administration and achieve a serum CRP level ≤6.0 mg/L to minimize the risk of postoperative SIRS.