Trifecta in flexible ureteroscopy for treatment of renal and upper ureteral calculi: A multicenter study

To determine predictors for missing trifecta in patients who underwent flexible ureteroscopy (FURS) for treatment of renal and upper ureteric calculi. The data of adult patients with renal or upper ureteral stones who underwent FURS from June 2021 through December 2022 were retrospectively reviewed. Stone-free status (no residual stones > 3 mm) was evaluated after 3 months with non-contrast CT. Modified Clavien classification was used to grade complications. A stone-free status after a single intervention of FURS without complications was defined as trifecta. Patients were divided into two groups (trifecta and non-trifecta). Risk factors for missing trifecta were compared between both groups using univariate and multivariate analyses. Three hundred twenty-three patients with mean age 48.9 ± 13 years and mean stone length 16 ± 5.9 mm were included. The trifecta criteria were applicable for 250 patients (71%). On multivariate analysis, risk factors for missing trifecta were stone multiplicity (OR: 3.326, 95%CI: 1.933-5.725) and non-experienced surgeons (OR: 1.819, 95%CI: 1.027-3.220). Multiple stones and performance of FURS by non-experienced surgeons are the independent risk factors for missing trifecta of FURS.