Cyclic voiding urosonography for detecting vesicoureteric reflux in renal transplant recipients.

BACKGROUND: The clinical significance of vesicoureteric reflux (VUR) in renal transplant recipients remains controversial. Voiding urosonography (VUS), a new modality for detecting VUR, can be used in these patients. The sensitivity of X-ray and radionuclide cystography for detecting VUR may be improved with cyclic procedures. The aim of our study was to evaluate whether cyclic VUS is superior to the single-cycle procedure. METHODS: Cyclic VUS was performed in 27 renal transplant recipients. Eight were children or adolescents and the remaining 19 recipients were adults. VUS was performed according to accepted guidelines. After the first micturition, the catheter was left in place and the entire procedure was repeated under the same conditions. RESULTS: Both initial cycle and cyclic VUS detected 17 out of 27 (63%) VURs in the same patients. The sensitivity was not improved by cyclic VUS. However, there were differences between the initial cycle and cyclic VUS (P=0.028) when comparing the number of negative results and the grades of VURs detected. This difference was even more pronounced when analysing only positive results. In the initial cycle, five out of 17 (29%) VURs were grade III, compared with 10 out of 17 (59%) grade III VURs in the same patients using the cyclic procedure (P=0.008). CONCLUSIONS: Cyclic VUS did not improve the detection sensitivity for VUR in our study. However, given that VUR grade may be important for the management of renal transplant recipients, the use of cyclic VUS may provide a useful diagnostic tool for these patients.

Echo-enhanced ultrasound voiding cystography in children: a new approach.

The development of echo-enhancing agents has significantly improved the detection of the movement of fluid within the urinary tract by ultrasonography (US). The purpose of our study was to compare ultrasound voiding cystography (USVC) for the detection of vesicoureteric reflux (VUR) in children with direct radionuclide voiding cystography (DRVC). Ninety-nine children, aged 1.1-12.3 years, with 198 potentially refluxing units, were investigated simultaneously by DRVC and USVC. The indications for cystography were urinary tract infection, follow-up of a previously detected VUR, and screening of siblings of children with VUR. During the investigation an echo-enhancing agent (Levovist) was administered intravesically through a catheter already in place for the DRVC. The movement of both agents, radiotracer and Levovist, was registered simultaneously by a computerized gamma camera and US, respectively. The results were analyzed with DRVC representing the reference diagnostic test. The overall sensitivity and specificity of USVC for the detection of VUR were 79% and 92%, respectively. USVC may represent a reliable diagnostic tool for the detection and follow-up of VUR in children.