Prospective Evaluation of Postoperative SIRS and Serum Inflammatory Indices in Percutaneous Nephrolithotomy Patients

This study aimed to evaluate the relationship between postoperative systemic inflammatory response syndrome (SIRS) and a broad set of 30 commonly used clinical parameters, along with novel acute inflammation predictive indices such as the systemic immune-inflammation index (SII), the aggregate index of systemic inflammation (AISI), and the systemic inflammation response index (SIRI), in patients undergoing percutaneous nephrolithotomy (PCNL).

A total of 233 patients aged 18-75 years who underwent PCNL were prospectively included. All clinical variables and serum-based inflammatory indices, including SII, SIRI, and AISI, were prospectively pre-defined in the study protocol prior to patient enrollment. All patients had sterile preoperative urine cultures and no known disease that could cause fever. Clinical characteristics, operative findings, laboratory parameters, and serum-based inflammatory indices (SII, SIRI, AISI) were recorded. The median preoperative stone size was 270.0 mm² (IQR: 180.0-447.0). Stone-free rates and postoperative SIRS development were assessed. Multivariate logistic regression analysis was used to determine independent predictors of SIRS. ROC analyses were conducted to evaluate the predictive performance of inflammatory indices.

The clinically significant stone-free rate was 89.3% (208/233), while the complete stone-free rate was 79.1% (182/233). Postoperative SIRS occurred in 75 patients (32.1%). According to multivariate logistic regression analysis, operation position, residual stone, white blood cell count (10³/µL), serum hemoglobin drop (g/dl), amount of physiological serum used (L), and positive renal pelvis urine culture were independently associated with SIRS. Inflammatory indices calculated from serum values, including SII, SIRI, and AISI, were directly associated with SIRS. ROC analysis demonstrated a moderate correlation between these indices and SIRS.

The findings of this prospective study indicate that postoperative SIRS risk can be predicted preoperatively and intraoperatively using a combination of commonly utilized clinical parameters and serum-based inflammatory indices. Higher values of SII, SIRI, and AISI were moderately predictive of SIRS development. Identifying high-risk patients prior to or during PCNL may help clinicians implement early preventive strategies and optimize postoperative management.