Castellani, Daniele, Somani, Bhaskar Kumar, Ferretti, Stefania, Gatti, Claudia, Sekerci, Cagri Akin, Madarriaga, Yesica Quiroz, Fong, Khi Yung, Campobasso, Davide, Ragoori, Deepak, Shrestha, Anil, Vaddi, Chandra Mohan, Bhatia, Tanuj Paul, Sinha, Mriganka Mani, Lim, Ee Jean, Teoh, Jeremy Yuen‑Chun, Griffin, Stephen, Tur, Anna Bujon, Tanidir, Yiloren, Traxer, Olivier, and Gauhar, Vineet
Objective: To assess outcomes of pre-stenting versus non-pre-stenting in children undergoing retrograde intrarenal surgery (RIRS) for intrarenal stones.Methods: Children/adolescent with kidney stones undergoing RIRS in 9 centers between 2015-2020 were retrospectively reviewed.Exclusion Criteria: ureteral lithotripsy, bilateral procedures. Stone-free status was evaluated at 3-month and defined as a single residual fragment (RF) ≤2 mm/absence of multiple fragments. Patients were divided into two groups (Group 1 no-pre-stenting; group 2 pre-stenting). Student's, Chi-square and Fisher's exact test was used to assess difference between groups. Univariable and multivariable logistic regression analysis were performed to predict RF. Statistical significance: p-value <0.05.Results: 389 children/adolescents were included (192 patients in Group 1). Pre-stented patients were younger compared with non-pre-stented (mean age 8.30±4.93 vs 10.43±4.30 years, p<0.001). There were no differences in stone characteristics (number, size, locations). Lasing and total surgical time were similar. Urinary tract infections were more prevalent in Group 2 (10.7%) compared to Group 1 (3.7%,p=0.016). Sepsis occurred in 2.1% of patients in Group 2 and no patient in Group 1 (p=0.146). 30.7% patients in Group 1 and 26.4% in Group 2 had RF (p=0.322). In univariate logistic regression analysis, stone size was associated with RF (OR 1.12 95%CI 1.06-1.18,p<0.001), whereas Thulium fiber laser with a lower incidence (OR 0.24 95%CI 0.06-0.69,p=0.020). Multivariate logistic regression analysis showed that stone size was associated with RF (OR 1.20 95%CI 1.08-1.36,p=0.001).Conclusions: RIRS showed similar stone-free rate in pre and non-pre-stented children/adolescents, although pre-stented patients were younger. A higher risk of post-operative infections was reported in pre-stented patients. [ABSTRACT FROM AUTHOR]