Trauma is an important cause of morbidity and mortality in the pediatric population, with approximately a fourth of all solid organ injuries being due to renal trauma.¹ The assessment and management of pediatric renal trauma has evolved significantly in the last several decades and thus far has mirrored that in the adult population. However, compared with adults, the pediatric kidney is more susceptible to injury due to previously described anatomical factors including lesser amounts of perirenal fat and larger relative size.^2,3 Identification of radiographic and clinical indicators has already been well established in the adult population,⁴ but due to the rarity of high-grade injuries in pediatric trauma, similar attempts have been primarily limited by small, single-institution series spanning decades. Furthermore, standardization for followup imaging and long-term monitoring of potential post-renal trauma sequelae such as hypertension and loss of renal function has not been well established in pediatric trauma.

Currently, followup CT imaging is recommended for all high-grade renal traumas in adults in the AUA Guidelines,⁵ but while CT provides excellent anatomical depictions, the not-insignificant amount of ionizing radiation exposure and associated increased risk of secondary malignancy are particularly worrisome for pediatric patients.^6,7 As such, given the limited data on pediatric high-grade renal injuries and subsequent followup monitoring, multi-institutional investigation is warranted to understand the current practice patterns and to develop guidelines specific for the pediatric population.

TRICK (Traumatic Renal Injury Collaboration for Kids) is a multi-institutional consortium that involved 5 level 1 pediatric trauma centers across the United States staffed by fellowship-trained pediatric urologists. Our aim was to gain a better understanding of the injury patterns of high-grade renal trauma and determine the utilization of radiographic imaging during hospitalization. Between 2007 and 2020, we identified 343 children less than 18 years old who sustained high-grade renal trauma, which was defined as grade 3 or higher using the American Association for the Surgery of Trauma grading system. Ultimately, 116 (34%) children underwent initial excretory phase CT (EPCT) scan, compared to 227 (66%) who received no dedicated excretory phase imaging. Between these 2 groups, we showed no difference in patient demographics, mechanism of injury, or grade of injury. The nonexcretory phase group experienced higher median injury severity score and splenic scores. After initial evaluation with EPCT, more children underwent endoscopic ureteral stent placement (7%) compared to those with non-EPCT imaging (1%, p =0.009). Length of hospitalization and discharge status were not statistically different, although more children with non-EPCT imaging received transfusions (p =0.02). Finally, compared to those with initial EPCT, patients with initial non-EPCT did not undergo more delayed imaging or experience higher rates of delayed surgical or radiological intervention, complications, or readmission rates within 90 days.

We believe our study demonstrates that pediatric high-grade renal trauma can be safely evaluated with non-EPCT scans during initial assessment, with no statistical difference in surgical outcomes or readmission rates. This study should help drive future prospective protocols to select pediatric patients with high-grade injury who may benefit from multiphase CT while minimizing radiation risk to those with self-resolving injuries.