Vesicoureteral reflux increases the risk of renal scars: a study of unilateral reflux

Abstract

The aim of this study was to assess the impact of vesicoureteral reflux (VUR) on renal scar following acute pyelonephritis by comparing the refluxing renal units with nonrefluxing renal units in children with unilateral primary VUR. Forty-eight children with unilateral primary VUR diagnosed after the first pyelonephritis were enrolled. Mean age of patients was 1.0+/-1.6 years (29 boys and 19 girls). All patients underwent renal ultrasonography and renal 99 m-technetium dimercaptosuccinic acid (DMSA) scan within three days following the diagnosis of pyelonephritis, and voiding cystourethrography (VCU) was performed soon after fever subsided and the infection was controlled. The DMSA scan was rechecked six months after the initial study when the first scan showed a renal defect. The first DMSA showed renal defects in 34 (70.8%) out of 48 of the refluxing renal units and in 13 (27.1%) out of 48 of the nonrefluxing renal units (P<0.01, OR: 6.54). At six months after the infection, 23 (47.9%) out of 48 refluxing renal units and seven (14.6%) out of 48 nonrefluxing renal units had renal scars on DMSA scan (P<0.01, OR: 5.39). The prevalence of renal scars did not vary significantly according to the grade of VUR. The CRP level on admission was significantly higher in patients with acute renal defect and scar. In conclusion, VUR increases the risk of post-pyelonephritic renal scars in children.

Predictors of renal scar in children with urinary infection and vesicoureteral reflux

“…On the other hand, renal scar rate in non-refluxing renal units at presentation in this group of children (7/64, 11%) was significantly lower than the scar rate in refluxing renal units (80/212, 38%, P=0.000). A similar finding has been reported previously by Lee et al in children with unilateral reflux [25].…”

Post-Inflammatory Nephropathy

“…However, an association between urinary tract infection in children with vesicoureteral reflux and renal scarring remains unquestionable (Faust et al, 2009;Jahnukainen et al, 2005;Muinuddin et al, 2008). This was confirmed by recent studies that demonstrated an increase in the risk of renal scarring after acute pyelonephritis in patients with vesicoureteral reflux (Kanellopoulos et al, 2006;Lee et al, 2006;Polito et al, 2006;Oh et al, 2008). Studies by Svensson et al (2005) and Mohanan et al (2008) disclosed that renal scarring was detected less frequently in infants with vesicoureteral reflux and without urinary tract infection than in those with vesicoureteral reflux and urinary tract infection.…”

Predictive value of clinical and laboratory variables for vesicoureteral reflux in children

“…The most concerning issue in an infant or child with UTI is the probability of underlying genitourinary anomalies and vesicoureteral reflux (VUR), which is frequently associated with renal scarring and eventually end-stage renal disease [1][2][3][4]. Therefore, the American Academy of Pediatrics recommends a voiding cystourethrography (VCUG) or radionuclide cystography at the earliest convenient time for children presenting with UTI [5].…”