Nuclear Cystometrogram-Determined Bladder Pressure at Onset of Vesicoureteral Reflux Predicts Spontaneous Resolution

Reflux Timing Is a Predictor of Successful Endoscopic Treatment of Vesicoureteral Reflux

OBJECTIVE

To determine whether vesicoureteral reflux (VUR) that occurs during either the filling or voiding phase on voiding cystourethrogram (VCUG) has prognostic significance on successful endoscopic treatment.

MATERIALS AND METHODS

A retrospective review was performed of 299 patients (438 ureters) with VUR who underwent endoscopic treatment with dextranomer/hyaluronic acid copolymer (Deflux) at a single institution from 2010 to 2013. Success was defined as absence of VUR on 3-month follow-up VCUG. Preoperative VCUGs were analyzed to determine whether the onset of VUR occurred during the filling or voiding phase. Predictor variables to determine success were analyzed, with a specific focus on VUR timing.

RESULTS

Success rate was 319/438 (72.8%) by ureter and 202/299 (67.6%) by patient. Reflux was seen during the filling and voiding phases in 290 and 148 ureters, respectively. Success rate was 203/290 (78%) for filling VUR and 116/148 (70%) for voiding VUR. Univariable analysis revealed voiding VUR had significantly increased odds of success (odds ratio [OR] 3.2, P = .049), while high-grade reflux (OR 0.53, P = .005) had significantly decreased odds of success. Multivariable analysis showed that voiding VUR (OR 3.2, P = .005) had significantly higher odds of success while those with high grade reflux (OR 0.42, P = .017) had significantly decreased odds of success.

CONCLUSION

The timing of VUR on preoperative VCUG appears to be an important independent predictor of successful endoscopic treatment of VUR. This has important clinical considerations when selecting VUR patients who would be best candidates for endoscopic treatment.

Continuous Antibiotic Prophylaxis in Pediatric Urology

Continuous antibiotic prophylaxis (CAP) for urinary tract infection prevention in children with vesicoureteral reflux, hydronephrosis, and hydroureteronephrosis is reviewed. A more selective use of CAP is advocated based on a review of known individual risk factors in each of these conditions that subsequently helps identify the children most likely to benefit from CAP. Both short-term and potential long-term side effects of CAP are reviewed, including the impact of prophylactic antibiotics on bacterial resistance and the microbiome. Alternatives to continuous antibiotic prophylaxis including Vaccinium macrocarpon (Cranberry), probiotics, and vaccines are reviewed.

Vesicoureteral reflux and continuous prophylactic antibiotics

Vesicoureteral reflux (VUR) management must be tailored based on the risk for further infections and renal scarring, gender, likelihood of spontaneous resolution, and parental preferences. Because we now understand that sterile VUR is benign and most reflux spontaneously resolves over time, the initial approach in majority of children is non-surgical with continuous antibiotic prophylaxis (CAP) and correction of bladder and bowel dysfunction. Despite increasing utilization of CAP over the past four decades, the efficacy of antibiotic prophylaxis has been questioned due to conflicting results of studies plagued with design flaws and inadequate subject sample size. The Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial, which was designed to address many of the limitations from previous studies, provided much needed answers. In this review, we sought to describe the controversy surrounding VUR management, highlight the results of RIVUR trial, and discuss how the RIVUR findings impact our understanding of CAP in the management of VUR.

Vesicoureteral Reflux in Pediatric Age: Where are we Today?

Although the diagnosis of vesicoureteral reflux and of reflux nephropathy is a well-established and shared procedure, its treatment nowadays is still very controversial. New developments on the knowledge of pathophysiology of renal damage associated to reflux opened the way towards a different diagnostic work-up and different therapeutic approaches.

Recently, the “top-down” diagnostic approach has gained wider interest, versus the “down-top” protocol. The attention has recently focused on the renal parenchyma damage and less interest has been given to the presence and the radiological degree of vesicoureteral reflux.

The review criteria were based on an in-depth search of references conducted on PubMed, using the terms “vesicoureteral reflux”, “children”, “incidence”, “etiology”, “diagnosis”, “treatment” and “outcomes”. The selection of the papers cited in this review was influenced by the content and the relevance to the points focused in the article.

Conservative approaches include no treatment option with watchful waiting, long-term antibiotic prophylaxis and bladder rehabilitation. The operative treatment consists of endoscopic, open, laparoscopic and robotic procedures to stop the refluxing ureter.

No final consensus has been achieved in literature yet, and further studies are necessary in order to better define the subset of children at risk of developing progression of renal damage.

This review aims to clarify the diagnostic management and the urological-nephrological treatment of reflux in pediatric age, on the basis of a review of the best-published evidence.

Distal ureteral diameter measurement objectively predicts vesicoureteral reflux outcome

OBJECTIVE

Vesicoureteral reflux (VUR) grading may be difficult when discrepancies exist between the degree of dilation of the pyelocalyceal system and the ureter. Resolution may be more accurately predicted by the appearance of the distal ureter. We analyzed a novel, objective method of evaluating VUR based on the diameter of the distal ureter.

METHODS

Seventy-nine voiding cystourethrograms were reviewed (18 boys; 61 girls; aged 1 month to 7.5 years). The largest ureteral diameter within the false pelvis was measured and normalized by dividing by the distance from the L1-L3 vertebral body to give the distal ureteral diameter: L1-L3 ratio (UDR). Clinical outcome was defined as spontaneous resolution or surgical correction.

RESULTS

A significant association between grade and UDR existed (p < 0.0001). Mean UDR was significantly greater in those who underwent surgical correction (0.34 ± 0.02 vs 0.18 ± 0.02; p < 0.0001). Logistic regression analysis demonstrated a significant association of UDR with outcome controlling for grade (p = 0.001). Grade effect on outcome when controlling for UDR was not significant (p = 0.76). Odds ratio for surgical correction corresponding to a 0.1 increase in UDR equaled 2.25 (95% CI: 1.39, 3.64).

CONCLUSION

UDR provides an objective measurement of VUR and appears more predictive of clinical outcome than grade in this series.

Diagnosis and management of vesicoureteral reflux in children

Critical evaluation of previously accepted dogma regarding the evaluation and treatment of vesicoureteral reflux (VUR) has raised significant questions regarding all aspects of VUR management. Whereas the standard of care previously consisted of antibiotic prophylaxis for any child with VUR, it is now unclear which children, if any, truly benefit from antibiotic prophylaxis. Operative intervention for VUR constitutes overtreatment in many children, yet there are limited data available to indicate which children benefit from VUR correction through decreased rates of adverse long-term clinical sequelae. Studies with longer follow-up demonstrate decreased efficacy of endoscopic therapy that was previously hoped to approach the success of ureteroneocystostomy. Prospective studies might identify risk factors for pyelonephritis and renal scarring without antibiotic prophylaxis. Careful retrospective reviews of adults with a history of reflux might allow childhood risk factors for adverse sequelae to be characterized. Through analysis of multiple characteristics, better clinical management of VUR on an individualized basis will become the new standard of care.

Is the mode of occurrence of vesicoureteral reflux correlated to bladder function and spontaneous resolution?

PURPOSE

To investigate whether mode of occurrence of vesicoureteral reflux (VUR), during micturition (M), during filling without increase in pressure (passive, P) or in response to an overactive contraction (OA), can be explained by differences in bladder function. Also, to study if the mode of occurrence of VUR can predict spontaneous resolution.

MATERIALS AND METHODS

There were 93 infants (68 boys and 25 girls) with VUR (grade III-V) included. Videocystometry was performed at median ages 5, 22 and 32 months registering grade and mode of reflux and bladder function characteristics.

RESULTS

Mode of occurrence of reflux changed with age. During infancy P, OA and M reflux comprised almost equal parts. At follow up, P reflux had increased and both OA and M reflux had decreased. This was partly due to a significantly higher probability of spontaneous resolution for M than P reflux, at 40 months (42 vs 18%). P and M reflux were significantly correlated to bladder function characteristics. P reflux was seen in children with high bladder capacity and occurred early in filling. Other predictors were higher age within the respective group and female sex. M reflux was correlated to lack of residual urine, low bladder capacity and absence of overactivity. Other indicators were male sex and low-grade reflux.

CONCLUSIONS

P and M reflux correlate to different bladder patterns: P with high bladder capacity and M with low bladder capacity and without signs of bladder dysfunction. M seems to be benign with a higher resolution rate.