https://doi.org/10.4081/aiua.2026.15512
Safety and outcomes of second-look percutaneous nephrolithotomy for complex renal stones: a retrospective study
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Published: 20 May 2026
Introduction: Residual stones after percutaneous nephrolithotomy (PCNL) remain a major clinical challenge, particularly in patients with large or complex calculi. Second-look PCNL offers a minimally invasive option for achieving complete stone clearance; however, realworld data on outcomes, timing, and predictive factors are limited.
Materials and methods: We retrospectively analyzed 72 patients who underwent second-look mini-PCNL at a high-volume tertiary center. Perioperative parameters were compared between procedures and between stone-free and residual stone groups. Stone-free status was defined as the absence of residual fragments ≥ 4 mm on non-contrast computed tomography. Outcomes of early (same admission) versus delayed second-look PCNL were evaluated.
Results: Most patients had high stone complexity, with 79.17% classified as Guy’s Stone Score grade 4. The overall stone-free rate after second-look PCNL was 55.56%. Multivariate analysis identified the presence of more than five stones as the only independent predictor of residual fragments (OR 6.49, 95% CI 1.65- 25.52; p = 0.007). Operative time and complication rates were comparable between procedures, while early re-intervention significantly reduced hospitalization duration and antibiotic use (both p < 0.01).
Conclusions: Despite a modest SFR, second-look PCNL is a safe and effective strategy for managing residual stones. Early reintervention during the same admission improves recovery and optimizes resource utilization.
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CRediT authorship contribution
Anh Toan Do: Conceptualization, Methodology, Supervision, Data interpretation, Writing – review & editing. Ngoc Thai Nguyen: Conceptualization, Methodology, Investigation, Data curation, Data interpretation, Writing – original draft. Shinnosuke Kuroda: Methodology, Data interpretation, Writing – review & editing, Critical revision of the manuscript for important intellectual content. Phan Nhat Duy Le: Investigation, Data curation, Formal analysis, Writing – original draft. Dao Thuan Nguyen: Methodology, Investigation, Data curation, Writing – review & editing. Huynh Dang Khoa Nguyen: Investigation, Data collection, Data curation, Formal analysis, Writing – original draft, Writing – review & editing. Xuan Thai Ngo: Methodology, Investigation, Data curation, Writing – review & editing. All authors reviewed the manuscript, approved the final manuscript for submission, agreed to take public responsibility for its content, and agreed to provide the underlying data upon reasonable request by the Editorial Office.
Supporting Agencies
Data Availability Statement
The data supporting the findings of this study are available from the corresponding author upon reasonable request.
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