Analysis of residual stones in patients and related influencing factors after percutaneous nephrolithotomy: a retrospective study.

We developed and validated a nomogram model to predict the risk of residual stones in patients who underwent percutaneous nephrolithotomy (PCNL) and identified the factors that influence this condition. We analyzed baseline and follow-up data from patients who underwent PCNL between January 2014 and December 2018, dividing them into development (n = 631) and validation (n = 157) groups. A risk scoring system was developed using the least absolute shrinkage and selection operator(LASSO) regression models and multivariate logistic regression analysis. After LASSO and multivariable adjustment in the development group, the history of surgery, urine culture, ureterostenosis, the number of stones, staghorn stones, stones in the middle calyx, stones in the lower calyx, stone burden, and CT value were selected to construct the nomogram model. The area under the receiver operating characteristic (ROC) curve (AUC) demonstrates great discrimination ability with an AUC of 0.873 (95% CI, 0.841 - 0.904) in the development group and an AUC of 0.902 (95% CI, 0.847 - 0.956) in the validation group. Calibration and decision curve analysis (DCA) curves demonstrate good prediction power and confirm the valuable clinical applications of this nomogram model. This tool assesses the risk factors for residual stones in patients undergoing PCNL. It is a simple, affordable, and highly credible tool that enables clinical workers to provide timely treatment.