Comparison of Stone Scoring Systems in Predicting Outcomes of Percutaneous Nephrolithotomy in Patients with Solitary Kidney

Objective: To assess efficacy of the Guy's Stone score (GSS) and Clinical Research Office of the Endourological Society (CROES) nomogram in predicting outcomes of percutaneous nephrolithotomy (PCNL) in patients with solitary kidney. Materials and Methods: Ninety patients with solitary kidney, who underwent PCNL between 2010 and 2018 in our center, were evaluated. Demographic characteristics and preoperative laboratory results of the patients were recorded. Operative time, duration of anesthesia, access number, stone location, supracostal access, stone-free (SF) rate, complication rate, nephrostomy tube removal time and length of hospital stay were recorded. Results: Data of patients with residual stones and SF patients were compared. In the analysis of groups; GSS, CROES score, stone burden, preoperative creatinine value, multiple accesses and presence of staghorn stone were found to be significant factors related with SF status. When data was evaluated according to complication status, stone burden, GSS, CROES score, multiple accesses and stone location were significant factors. In multivariate analysis, the most significant factors in predicting SF and complication status were CROES score (p=0.019) and stone burden (p=0.012), respectively. Conclusion: PCNL is an effective method in the treatment of stones in solitary kidney. CROES score is a better predictor of SF status in patients with solitary kidney. Patients with high stone burden are more prone to complications.