Abstract
BACKGROUND: Flexible ureteroscopy lithotripsy (FURL) is a prevalent intervention for the management of upper urinary tract stones (UUTS). Assessing the onset of systemic inflammatory response syndrome (SIRS) in patients during and postoperatively is a critical determinant in the decision-making process regarding the necessity of preoperative ureteral stenting prior to FURL. MATERIALS AND METHODS: A total of 340 patients with UUTS who underwent one-stage FURL were analyzed retrospectively. Least absolute shrinkage and selection operator and multivariate logistic regression analysis were used to screen out independent risk factors, subsequently developing a nomogram. The predictive performance was internally assessed using the concordance index (C-index), receiver operating characteristic curve, and calibration curve. Additionally, we evaluated the risk of SIRS in the context of one-stage FURL, considering the impact of various available variables. RESULTS: Age, urinary white blood cells, urine bacterial culture, and systemic immune-inflammation index (SII) were integrated to establish a nomogram for prediction of the risk of SIRS in patients undergoing one-stage FURL. The SII exhibited the highest odds ratio (OR = 30.356) for SIRS. The nomogram demonstrated a favorable predictive performance with a C-index of 0.964 (95% CI = 0.932-0.996), an area under the curve of 0.935, and a calibration curve validating its accuracy. We further developed a scoring system and classified the risk of SIRS into four grades. CONCLUSION: The developed nomogram and risk scoring system demonstrate favorable predictive ability and clinical serviceability for the personalized estimation of SIRS risk in UUTS patients undergoing one-stage FURL. It is advisable to place a ureteral stent prior to FURL in individuals with an SII exceeding 1,300 and meeting one of the following criteria: age > 60 years, urinary white blood cell levels of 1+/2+/3+, or positive urine bacterial culture. The insights provided may assist clinicians in selecting safer therapeutic approaches for UUTS patients.