Contrast-enhanced voiding urosonography with intravesical administration of ultrasound contrast agent for the diagnosis of pediatric vesicoureteral reflux

Abstract

Vesicoureteral reflux (VUR) is one of the most common urinary tract anomalies in children. It has been reported that VUR may be associated with reflux nephropathy. Ultrasound contrast-enhanced voiding urosonography (CeVUS) has become a routine diagnostic method for VUR in a number of European countries; however, it is not widely used in China. The aim of the present study was to analyze the clinical application and evaluate the safety of CeVUS as a diagnostic tool for VUR in children in order to establish a standardized operating procedure for CeVUS in pediatric VUR in China. Between August 2016 and October 2017, 90 children who were susceptible to VUR were admitted into the Pediatric Nephrology Department of Tongji Hospital and underwent CeVUS. The SonoVue second-generation USA contrast agent was administered intravesically via a transurethral bladder catheter at a dose of 1 ml. The occurrence of adverse events was monitored. Urine analysis and culture were performed. A total of 90 children (47 female, 43 male; mean age, 36.6 months) with 178 Pelvi-Ureteral Units (PUUs) underwent CeVUS to screen for VUR. VUR was detected in 44/90 pediatric patients (48.89%) and 65/178 PUUs (36.52%) by CeVUS. The grade distribution of the 65 PUUs with VUS was as follows: Grade I, 3; Grade II, 9; Grade III, 14; Grade IV, 22; and Grade V, 17. The accuracy of CeVUS in the present study were consistent with previous reports. No urethral anomalies were detected and there were no adverse events. CeVUS was demonstrated to be a safe, accurate and reliable imaging technique for detecting VUR in high-risk children, including neonates. Results of the present study indicated that CeVUS can be adopted as the primary screening and follow-up method for pediatric VUR diagnoses in China.

Keywords: children; contrast-enhanced voiding urosonography; urinary tract infection; vesicoureteric reflux.

Figure 1.

Two-dimensional ultrasound image of repetitive kidney, which has left side complication with hydronephrosis. The upper collecting system is separated with reciprocal connection of the echo-free region (arrow head), while the lower collecting system is not separated (arrow). L, left; R, right.

Figure 2.

(A) Two-dimensional ultrasound image and (B) contrast-enhanced voiding urosonography images of the kidney in which the left side exhibits complication with hydronephrosis. A contrast agent was present in the upper collecting system (arrow head) and an expanded tortuous ureter was observed (arrow). The contrast agent did not appear in the lower collecting system (star).

Figure 3.

(A) Two-dimensional ultrasound image and (B) contrast-enhanced voiding urosonography image of a Grade I vesicoureteral reflux on the left side. The contrast agent appeared intermittently in the ureter (arrow) but not in the pelvis.

Figure 4.

(A) Two-dimensional ultrasound image and (B) contrast-enhanced voiding urosonography image of a Grade II VUR on the right side. Contrast agent appeared in the pelvis and ureter without expansion of the pelvis (arrow).

Figure 5.

(A) Two-dimensional ultrasound image and (B) contrast-enhanced voiding urosonography image of a Grade III vesicoureteral reflux on the left side. Contrast agent appeared in the pelvis and ureter with mild expansion of the pelvis (arrow).

Figure 6.

(A) Two-dimensional ultrasound image and (B) contrast-enhanced voiding urosonography image of a Grade IV vesicoureteral reflux on the left side. Contrast agent appeared in the pelvis and ureter with expansion of the pelvis and the appearance of carunclulae papillaris (arrow).

Figure 7.

(A) Two-dimensional ultrasound image and (B) contrast-enhanced voiding urosonography image of a Grade V vesicoureteral reflux on the left side. The contrast agent appeared in the pelvis and ureter with clear expansion of the pelvis and calices, and disappearance of carunclulae papillaris (arrow).