International Reflux Study Research Articles

Update on imaging recommendations in paediatric uroradiology: the European Society of Paediatric Radiology workgroup session on voiding cystourethrography.

Voiding cystourethrography (VCUG) is a fluoroscopic technique that allows the assessment of the urinary tract, including the urethra, bladder, and-if vesicoureteral reflux (VUR) is present-the ureters and the pelvicalyceal systems. The technique also allows for the assessment of bladder filling and emptying, providing information on anatomical and functional aspects. VCUG is, together with contrast-enhanced voiding urosonography (VUS), still the gold standard test to diagnose VUR and it is one of the most performed fluoroscopic examinations in pediatric radiology departments. VCUG is also considered a follow-up examination after urinary tract surgery, and one of the most sensitive techniques for studying anatomy of the lower genitourinary tract in suspected anatomical malformations. The international reflux study in 1985 published the first reflux-protocol and graded VUR into five classes; over the following years, other papers have been published on this topic. In 2008, the European Society of Paediatric Radiology (ESPR) Uroradiology Task Force published the first proposed VCUG Guidelines with internal scientific society agreement. The purpose of our work is to create a detailed overview of VCUG indications, procedural recommendations, and to provide a structured final report, with the aim of updating the 2008 VCUG paper proposed by the European Society of Paediatric Radiology (ESPR). We have also compared VCUG with contrast-enhanced VUS as an emergent alternative. As a result of this work, the ESPR Urogenital Task Force strongly recommends the use of contrast-enhanced VUS as a non-radiating imaging technique whenever indicated and possible.

This Month in Pediatric Urology

You have accessJournal of UrologyThis Month in Pediatric Urology1 Dec 2022This Month in Pediatric Urology Julian Wan Julian WanJulian Wan More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003003AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail Improved Vesicoureteral Reflux Assessment With Simple and Machine Learning Approaches An important step to treating any disease is to accurately describe and classify its presentation. Reproducible designation of stage or severity allows for meaningful analysis. This is particularly true when pooling data and running multicenter trials. Superficially, one would expect this effort to be simple, robust, and easily portable. Methods based on an interval scale (eg, height in centimeters, blood pressure in millimeters of mercury), appear to be straightforward but require consistent mensuration. Categorical methods need clear, consistent descriptions and assignment (eg, egg sorting into small, medium, large, extra-large by a template). One might assume that the classification of vesicoureteral reflux (VUR) might be a simple matter given the widespread use of the International Reflux Study system and the ready availability of illustrations and examples.1 Despite these aids, the agreement of VUR has been low. One notion advanced to resolve this issue is to automate the process. Khondker et al (page 1314) describe a multi-institutional effort to assess the utility of a machine learning system (qVUR) to help improve VUR grading reliability.2 Using data gathered from 1,492 kidneys with over 8,000 independent grades the human inter-rater reliability was only 0.44 and there was low intra-rater reliability. The program was an improvement and achieved an accuracy of 62%. The program notably does not consider calyceal dilation or distortion because the finding was too easily confounded by contrast volume and kidney rotation. While this improvement may seem small, further testing after training showed a threefold improvement on grading reliability. While novel to medicine, the use of machines to perform measurements and improve quality assessment in commercial manufacturing is widespread. The mass manufacture of complex devices (eg, automobiles, airplanes, computers) while keeping high quality has been possible in part due to automated quality assessment and improvement. A key part of this effort is the automation of quality assurance. Once a human quality assurance worker would periodically take random samples of components and carefully record and track variations. Now, machine vision systems can assess every widget and software can track the variation and note when these variations cease being random and start trending towards being out of tolerance. These methods are applicable to not just wholly manufactured products but also to items and processes where there is inherent natural variation, such as potato chips.3 Whether such machine systems for VUR will supplant human grading remains to be demonstrated. Improvements would help increase reliability and help create uniformly classified pools of data for large-scale research.

Can Impaired Distal Ureteral Contraction Detected by Urinary Ultrasonography Indicate Presence of VUR?

Objective: The aim of this study was to determine if impaired distal ureteral contraction detected by urinary ultrasonography (US) could predict presence of vesicoureteral reflux (VUR). Materials and Methods: A Retrospective analysis of patients’ files between November 2016 and September 2020 was performed. A total of 248 children with demonstrated VUR on voiding cystourethrogram (VCUG) and who underwent urinary US within one week of the VCUG examination were included in the study. The degree of hydronephrosis was classified as per Society for Fetal Urology grading system and grading of VUR was done by the International Reflux Study Group grading system. The impaired distal ureteral contraction was defined as the reduced movement of the distal ureter as well as the deficiency of urine discharge into the bladder. Results: There was a significant correlation between the grade of VUR and the grade of hydronephrosis (p=0.0028). Also, the presence of distal ureteral dilation was related to increasing grades of VUR (p=0.001). The impaired distal ureteral contraction was present only in children with dilating VUR (grades III IV V) while its relationship between VUR grade was significantly high for grades IV and V VUR (p=0.001). Conclusion: In children, the impaired distal ureter contraction as well as the increase of grades of hydronephrosis, and the presence of distal ureteral dilation may aid decision-making in terms of requesting VCUG to detect dilating VUR.

Allograft Vesicoureteral Reflux after Kidney Transplantation.

Allograft vesicoureteral reflux (VUR) is a leading urological complication of kidney transplantation. Despite the relatively high incidence, there is a lack of consensus regarding VUR risk factors, impact on renal function, and management. Dialysis vintage and atrophic bladder have been recognized as the most relevant recipient-related determinants of post-transplant VUR, whilst possible relationships with sex, age, and ureteral implantation technique remain debated. Clinical manifestations vary from an asymptomatic condition to persistent or recurrent urinary tract infections (UTIs). Voiding cystourethrography is widely accepted as the gold standard diagnostic modality, and the reflux is generally graded following the International Reflux Study Committee Scale. Long-term transplant outcomes of recipients with asymptomatic grade I-III VUR are yet to be clarified. On the contrary, available data suggest that symptomatic grade IV-V VUR may lead to progressive allograft dysfunction and premature transplant loss. Therapeutic options include watchful waiting, prolonged antibiotic suppression, sub-mucosal endoscopic injection of dextranomer/hyaluronic acid copolymer at the site of the ureteral anastomosis, and surgery. Indication for specific treatments depends on recipient’s characteristics (age, frailty, compliance with antibiotics), renal function (serum creatinine concentration < 2.5 vs. ≥ 2.5 mg/dL), severity of UTIs, and VUR grading (grade I-III vs. IV-V). Current evidence supporting surgical referral over more conservative strategies is weak. Therefore, a tailored approach should be preferred. Properly designed studies, with adequate sample size and follow-up, are warranted to clarify those unresolved issues.

Assessment of the Grades of Vesicoureteral Reflux in Stented Ureters: An Experimental Study

Introduction: The aim of this experimental study is to assess, in a porcine model, the onset and grades of vesicoureteral reflux associated with ureteral stents. Methods: Twenty-four female porcine models were used. A 4.7-Fr ureteral stent was placed in all right ureters and kept in place for 6 weeks. Follow-ups were performed on weeks 1, 3, 6, and 12. Ultrasonography, cystoscopy, and fluoroscopy were used to analyze grade of hydronephrosis, presence and grade of vesicoureteral reflux, bacteriuria, and macroscopic changes of the ureteral orifices. Vesicoureteral reflux was classified using a modification of the International Reflux Study Committee grades. Results: 91.7% animals present vesicoureteral reflux, 89.5% grade IA, 3.5% grade IB, and 7% grade II. There is a significant increase in reflux during follow-ups at 3 and 6 weeks, whereas 6 weeks after removal, 26.3% of the ureters still present vesicoureteral reflux. Hydronephrosis and macroscopic changes of the ureteral orifice increase significantly with stenting, but there is no significant association between them and vesicoureteral reflux; the relationship between bacteriuria and the presence of vesicoureteral reflux is not significant either. Conclusion: Vesicoureteral reflux caused by ureteral stents in an animal model is mostly low grade and mainly affects the distal ureter.

Establishing a Standard Protocol for the Voiding Cystourethrography.

The voiding cystourethrogram (VCUG) is a frequently performed test to diagnose a variety of urologic conditions, such as vesicoureteral reflux. The test results determine whether continued observation or an interventional procedure is indicated. VCUGs are ordered by many specialists and primary care providers, including pediatricians, family practitioners, nephrologists, hospitalists, emergency department physicians, and urologists. Current protocols for performing and interpreting a VCUG are based on the International Reflux Study in 1985. However, more recent information provided by many national and international institutions suggests a need to refine those recommendations. The lead author of the 1985 study, R.L. Lebowitz, agreed to and participated in the current protocol. In addition, a recent survey directed to the chairpersons of pediatric radiology of 65 children's hospitals throughout the United States and Canada showed that VCUG protocols vary substantially. Recent guidelines from the American Academy of Pediatrics (AAP) recommend a VCUG for children between 2 and 24 months of age with urinary tract infections but did not specify how this test should be performed. To improve patient safety and to standardize the data obtained when a VCUG is performed, the AAP Section on Radiology and the AAP Section on Urology initiated the current VCUG protocol to create a consensus on how to perform this test.

A 5-year retrospective analysis of patients with primary vesicoureteral reflux undergoing open surgery; an assessment of 60 patients

Vesicoureteral reflux (VUR) describes the backward flow of urine from the bladder to the ureter and/or kidney. In this study, 60 patients below 18 years of age diagnosed with primary VUR in our clinic between 2010 and 2014 and undergoingureteroneocystotomy using various open surgery techniques were evaluated retrospectively. Diagnosis of VUR was based on voiding cystourethrography (VCUG). Urinary system ultrasonography (USG) was performed to exclude possible additional pathologies and to monitor the clinical course. Static renal scintigraphy (DMSA) was performed to determine preoperative renal scars and loss of function. Severity of reflux was divided into 5 degrees (1-5) following the criteria set out by the International Reflux Study Group. Patients were divided into 3 groups, mild (grade 1-2), moderate (grade 3) or severe (4-5) VUR. Females constituted 71.7% of the patients (n=43). Mean age at time of diagnosis of VUR was 6.25 years and mean age at time of surgery was 6.36 years. Fifteen percent of VURs were on the right side (n=9), 31.7% were on the left side (n=19) and 53.3% were bilateral (n=32). Advanced grade VUR (grade 4-5) was determined in 68.3% of patients. Loss of function was observed in 27.7% (n=16) of patients undergoing DMSA, and scar and loss of function were determined in 46.7% (n=28). The most common pathogen grown in preoperative urine cultures was Escherichia coli (65%). No significant difference was observed between the VUR grades in terms of age at time of diagnosis or age at time of surgery (p=0.682 and p=0.673, respectively). No statistically significant correlation was also determined between gender and VUR grade (p=0.859). No patient required a second surgical procedure. At postoperative follow-up, hypertension was observed in two patients, and these received antihypertensive therapy. Hypertension was observed over the long-term in one patient and was controlled with antihypertensive therapy. In conclusion, a high level of loss of renal function and scars was determined, in parallel with greater age at time of diagnosis of VUR and at time of surgery, in our region.

Technique of Tubularized Bladder Mucosa Method for Treating Recurrent Vesicoureteral Reflux.

Technique of Tubularized Bladder Mucosa Method for Treating Recurrent Vesicoureteral Reflux.

Bladder Volume at Onset of Vesicoureteral Reflux is an Independent Risk Factor for Breakthrough Febrile Urinary Tract Infection

Improved identification of children with vesicoureteral reflux at risk for recurrent febrile urinary tract infection may impact management decisions. We hypothesized that reflux occurring earlier during bladder filling increases the duration of exposure of the kidneys to bacteria, and, therefore, increases the risk of pyelonephritis. Children with vesicoureteral reflux and detailed voiding cystourethrogram data were identified. Bladder volume at onset of reflux was normalized for age. Demographics, reflux grade, laterality, presence/absence of bladder-bowel dysfunction and breakthrough febrile urinary tract infections were assessed. Median followup was 24 months (IQR 12 to 52). A total of 208 girls and 47 boys were analyzed with a mean ± SD age at diagnosis of 3.1 ± 2.6 years. On univariate analysis history of febrile urinary tract infection (HR 2.17, 95% CI 1.33-2.85, p = 0.01), dilating vesicoureteral reflux (HR 1.6, 95% CI 1.05-2.42, p = 0.03) and bladder-bowel dysfunction (HR 1.66, 95% CI 0.99-2.75, p = 0.05) were associated with an increased risk of breakthrough febrile urinary tract infection. Median bladder volume at onset of reflux in children with breakthrough febrile urinary tract infection was significantly less (33.1%) than in those without infection (49.5%, p = 0.003). Reflux onset at 35% predicted bladder capacity or less was associated with a significantly increased risk of breakthrough febrile urinary tract infection on multivariate analysis (HR 1.58, 95% CI 1.05-2.38, p = 0.03). Children with early filling vesicoureteral reflux are at increased risk for breakthrough febrile urinary tract infection independent of reflux grade. Bladder volume at onset of reflux should be recorded during cystograms since it provides additional prognostic information about the risk of pyelonephritis and resolution, and may assist with counseling and clinical decision making.

Cross-Sectional Study of Determinants of Upper and Lower Urinary Tract Outcomes in Adults with Spinal Dysraphism—New Recommendations for Urodynamic Followup Guidelines?

Although annual urodynamic study is currently recommended for all adults with spinal dysraphism, this followup might be overly intensive. Therefore, in this cross-sectional study we examine which determinants of upper and lower urinary tract outcomes are associated with relevant urodynamic findings. All patients visiting our specialized outpatient clinic foradults with spinal dysraphism during a 26-month period underwent evaluation of the lower urinary tract by (video)urodynamic study. High end filling pressure (40 cm H2O or greater), poor compliance (less than 10 ml/cm H2O) and high detrusor leak point pressure (40 cm H2O or greater) were classified as relevant findings and together called unsafe bladder. Multivariable analysis was performed to reveal determinants of unsafe bladder (type of spinal dysraphism, being wheelchair bound, hydrocephalus, urological symptoms and renal dilatation) and diagnostic accuracy was calculated for the significant determinants. Of the 134 patients evaluated (median age 31.5 years) 120 underwent complete urodynamic study and were included in this study. In the multivariable model unsafe bladder was significantly associated with being wheelchair bound (OR 5.36, p=0.008). In patients without symptoms who were not wheelchair bound the negative predictive value of urodynamic study for finding an unsafe bladder was high (1.00). If an adult patient with spinal dysraphism is not wheelchair bound, unfavorable findings at urodynamic study are unlikely. If these patients are asymptomatic, these findings are even more unlikely. In these patients it isprobably not necessary to perform urodynamic study as frequently as is currently recommended. Patients with an unsafe bladder need active surveillance and treatment when upper tract safety is threatened.

New Contralateral Vesicoureteral Reflux after Unilateral Ureteral Reimplantation: Predictive Factors and Clinical Outcomes

Although unilateral ureteral reimplantation for vesicoureteral reflux is highly successful, new contralateral reflux will develop postoperatively in some patients. We examined predictors and clinical outcomes of postoperative contralateral vesicoureteral reflux. We reviewed patients who underwent nontapered unilateral reimplantation for primary vesicoureteral reflux graded on a 3-point scale at our institution from January 1990 to December 2002, and identified those with subsequent contralateral vesicoureteral reflux. We analyzed the association of patient/procedure characteristics with incidence, and time to resolution of contralateral reflux and postoperative urinary tract infection. Multivariable models controlled for variables associated with incidence and time to resolution of contralateral reflux. A total of 395 patients (77.2% female, median age 5.3 years) underwent ureteral reimplantation for vesicoureteral reflux. Preoperative reflux was grade 1 in 2.8% of patients, grade 2 in 56.6% and grade 3 in 40.6%. Technical success was 95.4%. After reimplantation 39 patients (9.9%) had new contralateral reflux (grade 1 in 7, grade 2 in 27 and grade 3 in 5). Median followup was 51.8 months. On multivariate analysis younger age (less than 6 years, OR 3.7, p = 0.006) and low observed bladder capacity as percent of predicted bladder capacity (less than 50% of predicted capacity, OR 6.3, p = 0.02) were significant predictors of contralateral reflux. Contralateral reflux resolved in 21 of 27 patients (77.8%) on subsequent cystography at a median of 21.5 months. Two patients underwent reimplantation for persistent contralateral reflux. Four of 39 patients (10.3%) with contralateral reflux had postoperative febrile urinary tract infections at a median of 26 months, with spontaneous resolution of contralateral reflux in all. Younger patients and those with low observed vs predicted bladder capacity may be at increased risk for postoperative contralateral vesicoureteral reflux. A majority of contralateral reflux will resolve spontaneously, and the clinical course is typically benign.

Prospective Study Using a New Bulking Agent for the Treatment of Vesicoureteral Reflux: Polyacrylamide Hydrogel

Vesicoureteral reflux is frequently diagnosed in the pediatric population. Endoscopic treatment has become a popular form of first-line therapy. Available products offer good short-term success rates. However, the cost of these injected implants is an issue. We evaluated the success of endoscopic treatment for vesicoureteral reflux using polyacrylamide hydrogel. We performed a single center, single surgeon, prospective, off-label study using polyacrylamide hydrogel to treat vesicoureteral reflux. All patients underwent endoscopic subureteral double hydrodistention implantation technique injection followed by renal ultrasound and voiding cystourethrogram at 3 months postoperatively to confirm the absence of de novo hydronephrosis and correction of vesicoureteral reflux (grade 0). A total of 40 patients (69 refluxing ureters) underwent polyacrylamide hydrogel injection. Median age at surgery was 50 months. Bilateral reflux was identified in 29 patients (73%). Nine patients had duplex systems, 2 with reflux into both moieties. Reflux was graded using the International Reflux Study in Children grading system, with grade I seen in 9 ureters, II in 17, III in 20, IV in 18 and V in 5. Mean volume injected was 1.1 ml. Success rate for grade I to III vesicoureteral reflux at 3 months after a single treatment was 87%, and the overall success for all grades was 81.2%. Off-label use of polyacrylamide hydrogel injection therapy for primarily low grade vesicoureteral reflux demonstrates that the technique and short-term success rates are comparable to the most popular bulking agent, dextranomer/hyaluronic acid. These results suggest that further trials comparing polyacrylamide hydrogel and dextranomer/hyaluronic acid would be worthwhile.

Outcomes of Targeted Treatment for Vesicoureteral Reflux in Children with Nonneurogenic Lower Urinary Tract Dysfunction

There is a known association between nonneurogenic lower urinary tract conditions and vesicoureteral reflux. Whether reflux is secondary to the lower urinary tract condition or coincidental is controversial. We determined the rate of reflux resolution in patients with lower urinary tract dysfunction using targeted treatment for the underlying condition. Patients diagnosed and treated for a lower urinary tract condition who had concomitant vesicoureteral reflux at or near the time of diagnosis were included. Patients underwent targeted treatment and antibiotic prophylaxis, and reflux was monitored with voiding cystourethrography or videourodynamics. Vesicoureteral reflux was identified in 58 ureters in 36 females and 5 males with a mean age of 6.2 years. After a mean of 3.1 years of treatment reflux resolved with targeted treatment in 26 of 58 ureters (45%). All of these patients had a history of urinary tract infections before starting targeted treatment. Resolution rates of vesicoureteral reflux were similar for all reflux grades. Resolution or significant improvement of reflux was greater in the ureters of patients with dysfunctional voiding (70%) compared to those with idiopathic detrusor overactivity disorder (38%) or detrusor underutilization (40%). Vesicoureteral reflux associated with lower urinary tract conditions resolved with targeted treatment and antibiotic prophylaxis in 45% of ureters. Unlike the resolution rates reported in patients with reflux without a coexisting lower urinary tract condition, we found that there were no differences in resolution rates among grades I to V reflux in patients with lower urinary tract conditions. Patients with dysfunctional voiding had the most improvement and greatest resolution of reflux. Additionally grade V reflux resolved in some patients.

Febrile Urinary Tract Infections After Ureteroneocystostomy and Subureteral Injection of Dextranomer/Hyaluronic Acid for Vesicoureteral Reflux—Do Choice of Procedure and Success Matter?

Despite success rates favoring ureteroneocystostomy over subureteral injection of dextranomer/hyaluronic acid for correction of vesicoureteral reflux, the reported incidence of postoperative febrile urinary tract infection favors the latter. We evaluated contemporary treatment cohorts for an association between correction of vesicoureteral reflux and risk of postoperative febrile urinary tract infection. We retrospectively reviewed the records of 396 consecutive patients who underwent ureteroneocystostomy or subureteral injection of dextranomer/hyaluronic acid between 1994 and 2008. Time to event multivariate analyses included preoperative grade of vesicoureteral reflux and bladder/bowel dysfunction. Of 316 patients meeting study criteria 210 underwent ureteroneocystostomy (356 ureters) and 106 underwent subureteral injection of dextranomer/hyaluronic acid (167). Median patient age was 5.7 years (IQR 3.4 to 8.3). Median followup was 28 months (IQR 8 to 61). Ureteral success was significantly greater after ureteroneocystostomy (88%, 314 of 356 cases) vs subureteral injection of dextranomer/hyaluronic acid (74%, 124 of 167, p = 0.0001). When controlling for preoperative grade of vesicoureteral reflux and bladder/bowel dysfunction, the risk of persistent reflux was 2.8 times greater after subureteral injection of dextranomer/hyaluronic acid (95% CI 1.7-4.7, p <0.0001). The incidence of febrile urinary tract infection did not significantly differ between ureteroneocystostomy (8%, 16 of 210 cases) and subureteral injection of dextranomer/hyaluronic acid (4%, 4 of 106; HR 1.96, 95% CI 0.64-5.9, p = 0.24) even when controlling for preoperative grade of vesicoureteral reflux, a predictor of postoperative febrile urinary tract infection on multivariate analysis (HR 2.2 per increase in grade, 95% CI 1.3-3.6, p = 0.0022). Persistent reflux was not a predictor of postoperative febrile urinary tract infection (HR 0.81, 95% CI 0.22-2.9, p = 0.75 for ureteroneocystostomy vs HR 1.8, 95% CI 0.2-17.3, p = 0.6 for subureteral injection of dextranomer/hyaluronic acid and HR 1.8, 95% CI 0.3-3.3, p = 0.6 for both). The incidence of postoperative febrile urinary tract infection may be independent of radiographic procedural success.

The RIVUR Voiding Cystourethrogram Pilot Study: Experience with Radiologic Reading Concordance

Two reference radiologists independently review voiding cystourethrograms for the National Institutes of Health sponsored RIVUR (Randomized Intervention for Children with Vesicoureteral Reflux) trial for children with vesicoureteral reflux. A pilot study was required from all clinical centers before enrolling patients. Digital images were reviewed. Responses were compared and discrepancies adjudicated by teleconference to a final assessment. A total of 75 studies from 19 sites were reviewed. Discrepancies in vesicoureteral reflux grade level were noted on the left and right side in 11 (15%, kappa 0.85) and 12 (16%, kappa 0.83) ureters, respectively. Other areas of disagreement were the presence of paraureteral diverticulum (left 11%, kappa 0.31; right 9%, kappa 0.34), urethral anatomy (15%, kappa 0.33), whether the child voided (8%, kappa 0.21), the presence of ureteral duplication (left 7%, kappa 0.64; right 3%, kappa 0.78) and the presence of bladder trabeculation (5%, kappa 0.32). Of 83 ureters in which reflux was seen there was grade disagreement about 23 (28%). Of 61 ureters initially assessed as grade II or III reflux by both readers, there was disagreement on 9 (15%). Of these 9 discrepancies 7 (78%) were adjudicated to the higher grade (grade III). Discrepancies in the assessment of intermediate grade vesicoureteral reflux were noteworthy. Recommendations for patients with grade II or III reflux advanced by studies which rely on a single reading, which categorize only grade III or higher reflux as significant, may not be valid.

Single Center Experience with Endoscopic Subureteral Dextranomer/Hyaluronic Acid Injection as First Line Treatment in 1,551 Children with Intermediate and High Grade Vesicoureteral Reflux

In recent years the endoscopic injection of dextranomer/hyaluronic acid has become an established alternative to long-term antibiotic prophylaxis and the surgical management of vesicoureteral reflux. We determined the safety and effectiveness of the endoscopic injection of dextranomer/hyaluronic acid as first line treatment for high grade vesicoureteral reflux. Between 2001 and 2010, 1,551 children (496 male, 1,055 female, median age 1.6 years) underwent endoscopic correction of intermediate and high grade vesicoureteral reflux using dextranomer/hyaluronic acid soon after the diagnosis of vesicoureteral reflux on initial voiding cystourethrogram. Vesicoureteral reflux was unilateral in 761 children and bilateral in 790. Renal scarring was detected in 369 (26.7%) of the 1,384 patients who underwent dimercapto-succinic acid imaging. Reflux grade in the 2,341 ureters was II in 98 (4.2%), III in 1,340 (57.3%), IV in 818 (34.9%) and V in 85 (3.6%). Followup ultrasound and voiding cystourethrogram were performed 3 months after the outpatient procedure, and renal ultrasound was performed annually thereafter. Patients were followed for 3 months to 10 years (median 5.6 years). Vesicoureteral reflux resolved after the first, second and third endoscopic injection of dextranomer/hyaluronic acid in 2,039 (87.1%), 264 (11.3%) and 38 (1.6%) ureters, respectively. Febrile urinary tract infections developed during followup in 69 (4.6%) patients. None of the patients in the series needed reimplantation of ureters or experienced any significant complications. Our results confirm the safety and efficacy of the endoscopic injection of dextranomer/hyaluronic acid in the eradication of high grade vesicoureteral reflux. We recommend this 15-minute outpatient procedure as the first line of treatment for high grade vesicoureteral reflux.

Usefulness of Concomitant Autologous Blood and Dextranomer/Hyaluronic Acid Copolymer Injection to Correct Vesicoureteral Reflux

We present the long-term results of a new modification of endoscopic treatment of vesicoureteral reflux involving concomitant injection of autologous blood following the standard hydrodistention injection technique to prevent bulking agent leakage immediately after the procedure. A total of 341 children underwent endoscopic implantation of dextranomer/hyaluronic acid for vesicoureteral reflux. A subset of 171 patients underwent hydrodistention autologous blood injection, while 170 underwent classic hydrodistention injection. Frequency of symptomatic urinary tract infection after endoscopic treatment was recorded. Success was defined as absence of vesicoureteral reflux on postoperative voiding cystourethrography. A total of 523 ureters in 214 girls and 127 boys were treated. In patients undergoing hydrodistention autologous blood injection mean age was 39.48 months, mean maximal reflux grade was 3.02 and success rate was 93.6% after the first injection (98.0% in patients with grade II, 92.1% with grade III, 93.3% with grade IV and 85.7% with grade V reflux). In patients who underwent classic hydrodistention injection mean age was 36.12 months, mean maximal reflux grade 3.05 and success rate was 81.8% after the first injection (91.5% in patients with grade II, 89.4% with grade III, 74.4% with grade IV and 44.4% with grade V reflux). The success rate was significantly higher (p = 0.001) in patients undergoing hydrodistention autologous blood injection vs classic hydrodistention injection. Of the patients 1.7% in the hydrodistention autologous blood injection group and 2.9% in the classic hydrodistention injection group reported symptomatic urinary tract infection during followup. Immediate injection of autologous blood following dextranomer/hyaluronic acid injection to create a blood clot and barricade against bulking agent leakage is more effective than pure dextranomer/hyaluronic acid implantation. This novel modification stabilizes the subureteral implant mount and may affect the antireflux outcome.

Vesicoureteral Reflux

In the past 30 yr, the therapeutic approach to children with vesicoureteral reflux (VUR) has undergone a dynamic evolution from mainly surgery, as soon as VUR was detected, toward a conservative approach with antibiotic prophylaxis (stimulated and supported by results from the International Reflux Study in Children), to an endoscopic approach, and to the currently used active surveillance approach without prophylaxis. During those 30 yr, the diagnostic approach has not changed as much, although there is always an attempt to make the diagnosis of VUR while avoiding the “classic” voiding cystourethrogram (VCUG), which is one of the most stressing exams for a child and his or her family.Initially, radiographic grading of VUR was the only method of measuring the severity of VUR and of calculating the chance of spontaneous resolution. However, several other factors such as age, sex, presence of bladder and/or bowel dysfunction, presence of associated anatomic abnormalities, and laterality have been shown to have an influence on the spontaneous resolution rate.Based on the results of recent randomized studies (PRIVENT, Randomized Intervention for Children with Vesicoureteral Reflux [RIVUR], Swedish reflux study) and the updated VUR guidelines from the American Urological Association and the European Association of Urology–European Society for Pediatric Urology, this review will give an overview of the important clinical features of VUR, the diagnostic methods, the computer models and nomograms to detect which children with VUR should be treated, and the options their respective chances of success for treating patients. It will become clear that the treatment selection and decision for treating VUR in a child is an individualized process.

Pseudomonas Aeruginosa Urinary Tract Infection in Children: Risk Factors and Outcomes

Pseudomonas aeruginosa is an unusual uropathogen that is mostly responsible for nosocomial or catheter associated urinary tract infections in adults. Data about P. aeruginosa urinary tract infections in children are scarce. We investigated P. aeruginosa urinary tract infections in children in a well-defined area. Clinical, laboratory and radiological characteristics of all children with P. aeruginosa urinary tract infections were compared to those of gender matched children with community acquired Escherichia coli urinary tract infections during a 12-year period. A total of 35 children with 43 P. aeruginosa urinary tract infection episodes representing 6.7% of total urinary tract infection cases during the study period were compared to 70 children with E. coli urinary tract infections. Children with P. aeruginosa more often presented with a history of at least 1 previous urinary tract infection episode (p <0.0001), hospitalization (p = 0.0001), use of antibiotics (p = 0.0001), malformations predisposing to urinary tract infections (p = 0.004), vesicoureteral reflux (p <0.0001), abnormal dimercapto-succinic acid scan (p = 0.0003), longer hospitalization and surgery. Use of antibiotics either as prophylaxis or as treatment within the preceding 2 months was demonstrated by multivariate logistic regression analysis as the single independent risk factor for P. aeruginosa urinary tract infections (odds ratio 21.6, 95% CI 4.65-100, p = 0.0001). P. aeruginosa isolates were often resistant to gentamicin (27.9%) and ceftazidime (13.9%) but remained sensitive to carbapenems and ciprofloxacin. P. aeruginosa urinary tract infection is associated with distinct risk factors and outcomes, and should be considered in predisposed children with symptoms of urinary tract infection who are on prophylaxis or have a history of a recent course of antibiotics.

Vesicoureteral Reflux and Primary Bladder Neck Dysfunction in Children: Urodynamic Evaluation and Randomized, Double-Blind, Clinical Trial on Effect of α-Blocker Therapy

Primary bladder neck dysfunction has been under diagnosed as a treatable cause of vesicoureteral reflux. We evaluated the effect of prazosin administration on vesicoureteral reflux resolution and urodynamic parameters in children with idiopathic primary reflux and primary bladder neck dysfunction. A total of 62 children (mean ± SD age 7.9 ± 2.4 years) with documented vesicoureteral reflux and urodynamics proved primary bladder neck dysfunction were randomized to receive either 0.025 mg/kg α-blocker (prazosin, 40 patients) or placebo (22) nightly for 1 week with a subsequent increase to 2 divided doses. Patients were followed for 12 months with clinical evaluation and uroflowmetry performed every 2 months, and each patient underwent complete urodynamic study at 6-month intervals. In the placebo group no uroflowmetry or urodynamic parameter changed significantly at 1-year followup. A 60% decrease in reflux grade was observed in the treatment group compared to 17% in the placebo group. Mean maximal detrusor pressure, post-void residual and opening time were significantly decreased in both followup sessions in the prazosin group (p <0.05). Average flow rate improved from 4.30 to 12.80 ml per second at 6 months and to 13.10 ml per second at 12 months (both p <0.05). Special attention should be given to secondary causes of vesicoureteral reflux (such as primary bladder neck dysfunction, an underdiagnosed entity in children), since conventional treatment will most likely fail if these conditions are not addressed promptly. In this study prazosin was effective therapy for children with vesicoureteral reflux and primary bladder neck dysfunction.