Assessing the predictive value of scoring systems for stone-free success outcomes in pediatric mini percutaneous nephrolithotomy: a comprehensive retrospective analysis.

Kidney stone disease is relatively uncommon in pediatric populations, although its incidence has been steadily increasing in endemic regions. Mini-percutaneous nephrolithotomy (mini-PCNL), considered the most suitable approach for the treatment of large kidney stones, offers a minimally invasive option with fewer complications. This study evaluates the predictive accuracy of the STONE, Guy's Stone Score, and stone-kidney size (SKS) scoring systems in determining stone-free rates following pediatric mini-PCNL procedures. In this retrospective analysis, data were reviewed from 79 individuals younger than 18 who received mini-PCNL treatment from January 2021 to June 2024. Patients were evaluated as residual group and stone-free group. The diagnostic performance of the nomograms in detecting residual stones was evaluated using ROC analysis, and predictive factors for stone-free success were identified through logistic regression modeling. Guy's score (cut-off 1.5) had 79.3% sensitivity, 70% specificity, and AUC 0.817. The STONE score (cut-off 5.5) showed 69% sensitivity, 68% specificity, and AUC 0.741. SKS score (cut-off 3.5) resulted in 62.1% sensitivity, 78% specificity, and AUC 0.768. Logistic regression found stone size (OR: 1.137, p < 0.001) and volume (OR: 1.001, p < 0.001) were linked to stone-free success. Guy's score (OR: 5.438, p < 0.001), STONE score (OR: 1.741, p < 0.001), and SKS (OR: 3.972, p < 0.001) were strong predictors, but in multivariate analysis, only Guy's score (OR: 3.701, p = 0.010) remained significant. The results of our study demonstrate that the Guy's stone score is the most reliable prognostic tool for predicting stone-free success in pediatric patients undergoing mini-PCNL. Moreover, variables such as stone size and volume exert a substantial influence on the surgical outcomes.