CAN CAREFUL ULTRASOUND EXAMINATION OF THE URINARY-TRACT EXCLUDE VESICOURETERAL REFLUX IN THE NEONATE

The aim of the study was to determine whether a urinary tract appearin g normal when assessed by meticulous ultrasound (US) examination may c oexist with vesicoureteric reflux (VUR) and whether a normal US scan c an be used to exclude WR, thereby avoiding unnecessary voiding cystour ethrography (VCUG). The US features of 35 neonates with known VUR were reviewed. Criteria studied included pelvic dilatation above 7 mm on a transverse scan, calyceal or ureteral dilatation, pelvic or ureteral wall thickening, absence of the corticomedullary differentiation (CMD) and signs of renal dysplasia (small kidney, thinned or hyperechoic co rtex and cortical cysts); all signs that have been shown to result fro m or to be associated with VUR. 57 refluxing renal units (RRU) were fo und among the 35 patients. VUR was bilateral in 22. Among the 57 RRU, at least one US anomaly that would have prompted VCUG was present in 5 0 (87.7%). Pelvic dilatation above 7 mm was present in 29 RRU (50.9%) only. Calyceal dilatation was present in 24 RRU, the dilatation involv ing the calyces but not the renal pelvis in seven. Ureteral dilatation was observed in 15 RRU. Pelvic or ureteral wall thickening was presen t in seven RRU. CMD was absent in 32 RRU (56.1%). US signs of dysplasi a were found in 19 RRU. No US anomaly was found in seven RRU (12.3%) i n six patients. A careful and meticulous US examination of the neonata l urinary tract allows the detection of over 87% of RRU by showing at least one sonographic abnormality. It is concluded that a normal appea ring urinary tract on US does not usually coexist with VUR and that in such cases VCUG is not necessary.