Viaccoz, SandrineSandrineViaccozHeyne-Pietschmann, MarieMarieHeyne-PietschmannBerger, SteffenSteffenBerger0000-0002-9310-3548Zeino, MazenMazenZeino2026-02-052026-02-052026-01-08https://boris-portal.unibe.ch/handle/20.500.12422/231131Introduction The kidney is the most frequently injured organ in pediatric blunt abdominal trauma. The success of conservative treatment is well-demonstrated for American Association for the Surgery of Trauma (AAST) grade I-III renal injuries. However, the optimal management of grade IV trauma remains controversial. This study aims to enhance the understanding of the optimal therapeutic approach for children with such lesions.Materials And Methods Medical records of all children presenting with blunt abdominal trauma at our center between January 2013 and January 2020 were reviewed. Renal injuries were classified according to the 2018 AAST grading system, and mechanisms of injury were recorded. Detailed analysis was conducted on the patients with grade IV renal trauma, including mechanism of trauma, associated injuries, imaging, management, length of hospital stay, and follow-up.Results All 16 children with grade IV renal trauma were initially managed conservatively. Six (38 %) required no further intervention. Minimally invasive measures-ureteral stenting or angioembolization-were necessary for seven (43 %) patients. Urgent surgical exploration was needed in three (19 %) patients due to hemodynamic instability or vascular trauma. Nephrectomy was avoided in all three and no patient developed hypertension during follow-up. Renal function loss was observed in the only patient with renal arterial dissection.Discussion Approximately 40 % of our patients with grade IV blunt renal trauma were successfully managed conservatively. When including both conservatively and minimally invasively treated patients, the success rate rose to 80 %. Many injuries resulted from high-velocity winter sports accidents. This may have contributed to the severity of trauma at presentation.Conclusion Conservative management was initially attempted in all patients with grade IV blunt renal trauma and succeeded in 40 % of cases. The success rate rose to 80 % when minimally invasive treatments were included. High-velocity winter sports injuries were associated with more severe trauma, but conservative management remained feasible in hemodynamically stable patients. This highlights the importance of mechanism of injury in guiding treatment and the potential need to adapt pediatric grade IV renal trauma classifications to optimize timing of intervention.enConservativeInterventionalRenal traumaSurgicalUrinoma600 - Technology::610 - Medicine & healtharticle10.48620/944534163329610.1016/j.jpurol.2026.105726