Management of pediatric renal trauma with urinary extravasation: a retrospective study in a single clinical center

Abstract

Background: The majority of adult renal trauma patients choose conservative treatment, while the proportion of pediatric renal trauma patients requiring surgical intervention is higher than that of adult patients, especially grade IV renal trauma with urinary extravasation or urinoma. There has been an ongoing discussion about the need for timely surgical intervention in such pediatric patients. This study aims to investigate the therapeutic strategies of grade IV renal trauma with urinary extravasation in children.

Methods: A retrospective analysis was conducted on the diagnosis and treatment of 19 cases of pediatric grade IV renal trauma with urinary extravasation at Children's Hospital of Nanjing Medical University from December 2016 to December 2023.

Results: The cohort included patients with multiple injuries (n=7) and ureteropelvic junction ruptures (n=5). Initial assessment involved plain computed tomography (CT) scans for 14 patients, while 5 cases underwent delayed CT imaging to evaluate the extent of trauma. Treatment modalities included ultrasound-guided drainage of perinephric urinoma (n=2), cystoscopic double J-tube placement (n=7), nephrostomy (n=2), pelvic repair and pyeloureteroplasty (n=6), and calyceal-ureteral anastomosis (n=2). Follow-up ranged from 2 to 61 months, with an average of 15.9 months. The interventions demonstrated favorable outcomes, with complete recovery in 9 cases of urinoma drainage and ureteral stenting as evidenced by regular ultrasound monitoring. Two nephrostomy patients required revision surgery due to tube complications. Five of six cases who underwent pyeloureteroplasty recovered well, except for one who presented with moderate hydronephrosis, yet functional evaluation showed effective urinary excretion without significant obstruction. Both patients who received calyceal-ureteral anastomosis reported satisfactory healing.

Conclusions: Effective management of pediatric grade IV renal trauma with urinary extravasation necessitates comprehensive imaging, with delayed CT scanning serving as the modality of choice when permissible. Regular follow-up via ultrasound or CT is critical for conservatively managed cases. Surgical intervention should be considered for patients with ongoing urinary extravasation, expanding urinoma, post-traumatic hydronephrosis, or suspected ureteropelvic junction disruption. The therapeutic approach, including ureteral stenting, renal laceration repair, or calyceal-ureteral anastomosis, should be tailored to the individual patient's condition.

Keywords: Renal trauma; child; treatment; urinary extravasation.

Figure 1

Female, 7 years and 1 month old, fall injury resulting in rupture of the right kidney, contusion of the left kidney and contusion of the lungs. (A) CT suggests that a large amount of fluid has accumulated under the right renal pericardium and in the perinephric fat three days after the injury; (B) CT suggests that the perinephric fluid in the right kidney has been resorbed 25 days after perinephric urethrocystic puncture and drainage. CT, computed tomography.

Figure 2

Male, 5 years and 8 months old, fall injury resulting in left hydronephrosis rupture after trauma. CT suggests that the left renal silhouette is obviously enlarged, the renal pelvis and calyces are dilated, the left renal parenchyma is compressed bushy, the perinephric fat interstitial blurring, can see the watery density shadow encircling the left kidney, enhancement scan does not see abnormal strengthening, delayed scan can see the extravasation of the contrast medium. The left ureter was not clearly visible. CT, computed tomography.

Figure 3

Male, 2 years and 1 month old, left UPJ rupture, left lung contusion and rib fracture due to a traffic accident. (A) CT suggests a little exudation in the left perirenal space 1 day post-injury; (B) CT suggests a large encapsulated effusion visible in the perirenal space of the left kidney 9 days post-injury. CT, computed tomography; UPJ, ureteropelvic junction.

Figure 4

Details of the surgical intervention in 19 children with grade IV renal trauma with urinary extravasation. CT, computed tomography; MRU, magnetic resonance urography; MRCP, magnetic resonance cholangiopancreatography.