Safety and outcome of percutaneous nephrolithotomy in patients with solitary kidney: A tertiary care center experience

INTRODUCTION: Percutaneous nephrolithotomy (PCNL) for stones in solitary kidney poses a significant challenge and potential threat for acute kidney injury or progression of chronic kidney disease (CKD). We present our experience of PCNL in solitary functioning kidney (SFK) to evaluate the safety, efficacy, and postoperative complications and highlight the differences between these outcomes with respect to the stage of CKD. METHODS: We carried out a retrospective study of patients with SFK, who underwent PCNL at our center from April 2010 to March 2018. Patients who had a minimum of 6 months of follow-up were included. Patients were classified into CKD groups based on the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative. Group 1 included Stages 1, 2, and 3A and Group 2 included Stages 3B, 4, and 5. Postoperative complications and stone-free rate were recorded and graded according to the Clavien–Dindo classification and compared between the two groups. RESULTS: We had a total of 128 patients (Group 1 – 84 and Group 2 – 44). Stone-free rate after the first PCNL was higher in Group 1 as compared to Group 2 (88.1% [n = 74] vs. 50% [n = 22], P = 0.02). Overall, 48 patients (37.5%) had postoperative complications, but most were minor. Clavien Grade 1 and 2 complications were seen in 34 patients (Group 1, n = 18 and Group 2, n = 16, P = 0.069), whereas Grade 3 and 4 complications were seen in 14 patients (Group 1, n = 2 and Group 2, n = 12, P < 0.001), respectively. Need for postoperative (number of sessions) dialysis was seen with increased frequency in patients with higher chronic kidney stages (Group 1 vs. Group 2; 6 vs. 22 sessions, P < 0.001). CONCLUSION: PCNL in SFK is safe, with satisfactory outcome, but patients with advanced CKD stage have higher risk of complications including need for dialysis and may require multiple sessions for complete stone clearance. Hence, they should be managed at high output tertiary centers.