Contrast-enhanced ultrasonography (CEUS) in the management of pediatric renal injuries: where are we now?

Purpose: Experience with CEUS in management of kidney post-traumatic injuries is limited, especially in pediatric age. This paper aimed to identify: clinical settings in which CEUS could be used as first diagnostic tool, skipping CT; CEUS ability to detect complications during non-operative management (NOM); and CEUS role in patients with collecting system injuries. Methods: Patients with renal trauma admitted between 2003 and 2023 were enrolled in a retrospective study. At T0, CT was performed in case of high-energy trauma, CT or CEUS in case of low-energy or/and localized trauma. CEUS was used during follow up (FU) in case of suspected complications and to follow healing of the lesions and urinomas. Results: Among 22 patients included, at T0 20/22 performed CT, 1/22 CEUS and 1/22 baseline US. During NOM CEUS was necessary: in early FU to rule out complications in 3/22 (1 anemization and 2 hematuria); in middle FU in 14/22 to authorize mobilization/discharge and monitor urinomas; in outpatient setting in 2/22, to authorize return to sport activities. Overall, a collecting system injury was detected in 6 patients by CT and in 1 by CEUS. In 3/7 a perirenal urinoma developed. All were monitored with CEUS or baseline US. Conclusions: CEUS is useful as first imaging study in low-energy and localized trauma, but confidence with CEUS is still to be improved and spread, to replace CT in selected cases. CEUS is valuable for detecting complications, avoiding repeat CT in most of cases. In expert hands CEUS can identify and monitor leakage indirectly.