The Efficacy and Safety of Endoscopic Combined Intrarenal Surgery: Results of 261 Procedures in a Tertiary Referral Center

Introduction: To provide a comprehensive overview of the efficacy and safety of ECIRS procedures in a tertiary referral hospital. Methods: All ECIRS cases at a tertiary referral center for urolithiasis (Amsterdam UMC) between January 2018 and September 2023 were retrospectively reviewed. Predicted complexity of the operation was stated in Guy's stone score (GSS). Primary outcome was the stone-free rate (SFR) as determined by fragments <4 mm on noncontrast computed tomography (NCCT) at 6 weeks postoperatively. Secondary outcomes included endoscopic SFR and complication rate. Results: A total of 261 ECIRS procedures were included. Mean age was 54 years, and 58% of patients had a GSS of III or IV. Endoscopic SFR was 80%; however, NCCT showed a radiological SFR of 54%, with SFRs of 78%, 55%, 63%, and 40% for GSS I, II, III, and IV, respectively. Postoperative complications occurred in 23% of cases, with major complications (Clavien-Dindo grade ≥3) in 3.8%. Systemic inflammatory response syndrome developed in 8.0%, and a blood transfusion was administered in 3.8% of patients. Conclusion: ECIRS is an effective and safe option for the management of complex renal stones, although complete stone clearance was not achieved in all patients in this selected referral population. Endoscopic and radiological SFRs differ significantly, highlighting the impact of imaging modality on outcome interpretation. A higher GSS correlates with a lower SFR and a higher chance of complications.