Vineet Gauhar, Ee Jean Lim, B. Kumar Somani, Jaisukh Kalathia, Edgar Beltrán-Suárez, Gadzhiev Nariman, Mahmoud Laymon, Kremena Petkova, Esteban Acuña, Mohamed Amine Lakmichi, Khi Yung Fong, Marek Zawadzki, Nitesh Kumar, Amish Mehta, Roy Zen Sing Teng, Gopal Tak, А.Г. Мартов, Marcos Cepeda, Vigen Malkhasyan, Arun Chawla, Daniele Castellani, Thomas R. W. Herrmann, Steffi Kar Kei Yuen
BACKGROUND: Renal stones in anomalous kidneys pose surgical challenges due to altered anatomy. Miniaturized percutaneous nephrolithotomy (mini-PCNL) reduces morbidity, but concerns remain about stone-free rates (SFRs) and infection. Suction-assisted mini-PCNL (SM-PCNL) enhances fragment removal and controls intrarenal pressure, but its role in anomalous kidneys is unclear. OBJECTIVE: To evaluate perioperative outcomes of SM-PCNL in anomalous kidneys in a multicenter, real-world study and assess variations based on positioning, lithotripsy modality, and renal anomalies. METHODOLOGY: This prospective study across 15 centers (January-December 2024) included 287 adults undergoing SM-PCNL for renal stones in anomalous kidneys. Patients with normal anatomy, non-suction PCNL, or incomplete data were excluded. SFR was assessed via a 30-day non-contrast CT: 100% stone-free (Grade A), residual fragments ≤4 mm (Grade B), or >4 mm/multiple (Grade C, requiring reintervention). RESULTS: Malrotation (65.5%) was the most common anomaly, followed by duplex systems (25.1%), horseshoe kidneys (8.4%), and ectopic kidneys (1.0%). Median stone size was 1.7 cm. Supine positioning was used in 54.4%. Lithotripsy was performed with holmium laser (50.9%), thulium fiber laser (11.1%), or pneumatic lithotripsy (26.1%). Intraoperative clearance was 95.4%. At 30 days, 93.4% achieved Grade A, 5.6% Grade B, and 1.0% required reintervention. Complications were low; 0.7% had sepsis requiring intensive care unit admission. No transfusions or pleural injuries occurred. CONCLUSION: SM-PCNL using 18F suction sheaths with laser in a single stage achieved 93.4% complete SFR with negligible complications and minimal reintervention.