We suggest that vesicoureteral reflux is more common in children even without urinary-tract infection than has been thought previously. The guidelines recommending a search for reflux by means of voiding cystourethrography should be reconsidered.

The aim of this study was to estimate the prevalence of vesicoureteral reflux (VUR) and clinically significant ultrasonography (US) abnormalities in a large group of children with proven and suspected urinary tract infection (UTI). The medical reports on renal US and voiding cystouretrographies (VCUG) of 2,036 children were reviewed. Renal US was performed on all children and VCUG on 1,185 children (58%). Based on the urine culture data, the UTI diagnoses were classified into five reliability classes (proven, likely, unlikely, false and no microbial data). The UTI diagnose was considered proven in 583/2036 (28.6%) and false in 145 (7.1%) cases. The prevalence of VUR was similar among those with proven and false UTI [37.4 vs. 34.8%; relative risk (RR) 1.08, 95% confidence intervals (95% CI) 0.7-1.7, P = 0.75] and decreased with increasing age (P = 0.001). Clinically significant US abnormalities occurred in 87/583 (14.9%) cases with proven UTI and significantly less often (11/145, 7.6%) in the false UTI class (RR 1.96, 95% CI 1.1-3.6, P = 0.02). Our finding supports the claim that VUR is not significantly associated to UTI and that its occurrence among children even without UTI is significantly higher than traditional estimates. This challenges the recommendations of routine VCUG after UTI.

The combination of urinary tract infection (UTI) and vesicoureteral reflux (VUR) is commonly thought to predispose the child to pyelonephritis, renal scarring and, later in life, to hypertension or end-stage renal disease (ESRD). This paradigm has led to the active search, follow-up and treatment of VUR, and also prevention of recurrent UTI in children. The causality of VUR and ESRD is controversial, however. According to recent meta-analyses it is uncertain whether we can prevent renal scarring or ESRD by treating VUR. Studies on VUR are abundant, but the findings and conclusions are confounding. Because of the lack of evidence of the role of VUR, reasonable doubt has recently been presented on the rationale of imaging all children with UTI and treating the children with VUR. The overall importance of VUR is confounded because of the natural tendency of VUR to resolve spontaneously, its dynamic nature, and its different grades in children. The historical studies showing that VUR is much more common, even among healthy children, than usually claimed, have been forgotten. Since it seems that we are referring too many healthy children to unpleasant and possibly unnecessary imaging tests for VUR, we are uncertain when and what kind of VUR-if any-we should treat, and whether our present rationale of addressing VUR truly makes any difference to renal scarring or ESRD in children, we should critically revisit the subject of VUR.

No abstract

We suggest that children with UTI could be examined using US alone and to use VCUG only after additional indications.