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.

Urolithiasis. 2025 May 14*** epublish ***

Adem Altunkol, Ergün Alma, Hakan Anıl, Mert Hamza Özbilen, Buğra Aksay, Mehmet Eflatun Deniz

Department of Urology, University of Health Sciences, Adana City Teaching and Research Hospital, Adana, Turkey. ., Department of Urology, University of Health Sciences, Adana City Teaching and Research Hospital, Adana, Turkey., Faculty of Medicine, Department of Urology, İstanbul Aydın University, Istanbul, Turkey., Department of Urology, Baskent University, Adana Dr. Turgut Noyan Application and Research Center, Adana, Turkey.