Medical versus surgical treatment in children with severe bilateral vesicoureteric reflux and bilateral nephropathy: a randomised trial

Primary vesicoureteral reflux

Primary vesicoureteral reflux (VUR) is one of the most common urological abnormalities in infants and children. The association of VUR, urinary tract infection (UTI) and renal parenchymal damage is well established. The most serious complications of VUR-associated reflux nephropathy are hypertension and proteinuria with chronic kidney disease. Over the past two decades, our understanding of the natural history of VUR has improved, which has helped to identify patients at increased risk of both VUR and VUR-associated renal injury. The main goals in the treatment of paediatric patients with VUR are the prevention of recurrent UTIs and minimizing the risk of renal scarring and long-term renal impairment. Currently, there are four options for managing primary VUR in infants and children: surveillance or intermittent treatment of UTIs with management of bladder and bowel dysfunction; continuous antibiotic prophylaxis; endoscopic subureteral injection of tissue-augmenting substances; and ureteral reimplantation via open, laparoscopic or robotic-assisted surgery. Current debates regarding key aspects of management include when to perform diagnostic imaging and how to best identify the paediatric patients that will benefit from continuous antibiotic prophylaxis or surgical intervention, including endoscopic injection therapy and minimally invasive ureteral reimplantation. Evolving technologies, such as artificial intelligence, have the potential to assist clinicians in the decision-making process and in the individualization of diagnostic imaging and treatment of infants and children with VUR in the future.

Conflicting views of physicians and surgeons concerning pediatric urinary tract infection: a comparative review

BACKGROUND

A first febrile urinary tract infection (UTI) is a common condition in children, and pathways of management have evolved over time.

OBJECTIVE

To determine the extent to which pediatricians and surgeons differ in their investigation and management of a first febrile UTI, and to evaluate the justifications for any divergence of approach.

MATERIALS AND METHODS

A literature search was conducted for papers addressing investigation and/or management following a first febrile UTI in children published between 2011 and 2021. Searches were conducted on Medline, Embase, and the Cochrane Controlled Trials Register. To be eligible for inclusion, a paper was required to provide recommendations on one or more of the following: ultrasound (US) and voiding cystourethrogram (VCUG), the need for continuous antibiotic prophylaxis and surgery when vesicoureteral reflux (VUR) was detected. The authorship required at least one pediatrician or surgeon. Authorship was categorized as medical, surgical, or combined.

RESULTS

Pediatricians advocated less imaging and intervention and were more inclined to adopt a "watchful-waiting" approach, confident that any significant abnormality, grades IV-V VUR in particular, should be detected following a second febrile UTI. In contrast, surgeons were more likely to recommend imaging to detect VUR (p<0.00001), and antibiotic prophylaxis (p<0.001) and/or surgical correction (p=0.004) if it was detected, concerned that any delay in diagnosis and treatment could place the child at risk of kidney damage. Papers with combined authorship displayed intermediate results.

CONCLUSION

There are two distinct directions in the literature regarding the investigation of an uncomplicated first febrile UTI in a child. In general, when presented with a first febrile UTI in a child, physicians recommend fewer investigations and less treatment, in contrast to surgeons who advocate extensive investigation and aggressive intervention in the event that imaging detects an abnormality. This has the potential to confuse the carers of affected children.

A cross-sectional analysis of paediatric urologists' current practices, opinions and areas of perceived importance in the delivery of adolescent & transitional care

INTRODUCTION

Complex urological anomalies often require continued care as patients reach adulthood. Adequate transition for adolescents with ongoing urological care needs is critical to allow for seamless care in adult hospitals. Studies have shown that this can lead to improved patient and parental satisfaction, and lower utilisation of unplanned inpatient beds and emergency department visits. There is currently no ESPU-EAU consensus on the adequate mechanism and very few individual papers examining the role of urological transition for these patients in a European setting. This study aimed to identify current practice patterns in paediatric urologists providing adolescent/transitional care, to assess their opinions towards formal transition and to look for variations in care. This has implications for long-term patient health and specialist care.

METHODS

An 18-item cross-sectional survey was compiled and pre-approved through the EAU-EWPU and ESPU board offices prior to dissemination to all registered ordinary members affiliated with the ESPU. This was created using a mini-Delphi method through the EWPU research meetings to provide current semi-quantitative data relating to current opinions and attitudes of this cohort.

RESULTS

A total of 172 respondents (55% paediatric general surgery; 45% urology) across 28 countries completed the survey. The majority of respondents were in practice >10 years and spent >80% time in paediatric urology. There was no formal transition process according to 50% respondents and over half of those that did have less than 1/month, with <10% using validated questionnaires. More than two-thirds respondents continued to provide care after transition, as >70% units had no designated corresponding adult service. Furthermore, 93% paediatric believe a formal transition service to be very important, using a multidisciplinary framework. A pareto chart demonstrated 10 specific conditions to be of most interest in transition to adulthood.

CONCLUSION

This is the first study to assess the requirements of paediatric urologists for adequate transitional care, however due to the nature of the survey's distribution, this was a non-scientific poll based on a convenience sample of respondents. It is critical that dual-trained or adult-trained urologists with a specific interest in paediatric urology work with current paediatric urologists in a multidisciplinary fashion to facilitate early transition based on the adolescent's developmental and biopsychosocial requirements. National urological and paediatric surgical societies need to make transitional urology a priority. The ESPU and EAU should collaboratively consider developing transitional urology guidelines to allow a framework by which this can occur.

Tissue Immunity in the Bladder

The bladder is a major component of the urinary tract, an organ system that expels metabolic waste and excess water, which necessitates proximity to the external environment and its pathogens. It also houses a commensal microbiome. Therefore, its tissue immunity must resist pathogen invasion while maintaining tolerance to commensals. Bacterial infection of the bladder is common, with half of women globally experiencing one or more episodes of cystitis in their lifetime. Despite this, our knowledge of bladder immunity, particularly in humans, is incomplete. Here we consider the current view of tissue immunity in the bladder, with a focus on defense against infection. The urothelium has robust immune functionality, and its defensive capabilities are supported by resident immune cells, including macrophages, dendritic cells, natural killer cells, and γδ T cells. We discuss each in turn and consider why adaptive immune responses are often ineffective in preventing recurrent infection, as well as areas of priority for future research.

Do Various Treatment Modalities of Vesicoureteral Reflux Have Any Adverse Effects in Pediatric Patients? A Meta-Analysis

PURPOSE

Vesicoureteral reflux (VUR) is a risk factor for various renal problems like recurrent urinary tract infections (UTIs), pyelonephritis, renal scarring, hypertension, and other renal parenchymal defects. The interventions followed by pediatricians include low-dose antibiotic treatment, surgical correction, and endoscopy. This meta-analysis aimed to assess the advantages and drawbacks of various primary VUR treatment options.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, reference lists of journals, and abstracts from conference proceedings were all used to find randomized controlled trials. The articles were retrieved from 1985 till 2020. Twenty articles were used for the data analysis. Criteria for Selection: Surgery, long-term antibiotic prophylaxis, noninvasive techniques, and any mix of therapies are also options for treating VUR. Collection and Interpretation of Data: Two authors searched the literature separately, determining research qualifications, assessing accuracy, and extracting and entering results. The odds ratio (OR) of these studies was used to construct the forest plot. The random-effects model was used to pool the data. Also, the random-effects model was used with statistical significance at a p value < 0.05 to assess the difference in side effects after treatment of VUR using different modalities.

RESULTS

We found no statistically significant differences between surgery plus antibiotics and antibiotic alone-treated patients in terms of recurrent UTIs (OR = 0.581; 95% confidence interval [CI] 0.259-1.30), renal parenchymal defects (OR = 1.149; 95% CI 0.75-1.754), and renal scarring (OR = 1.042; 95% CI 0.72-1.50). However, the risk of developing pyelonephritis after surgical treatment of VUR was lesser than that in the conservative approach, that is, antibiotics (OR = 0.345; 95% CI 0.126-0.946.), positive urine culture (OR = 0.617; 95% CI 0.428-0.890), and recurrent UTIs were more common in the placebo group than in the antibiotic group (p < 0.05; OR = 0.639; 95% CI 0.436-0.936) which is statistically significant.

CONCLUSION

Based on current research, we recommend that a child with a UTI and significant VUR be treated conservatively at first, with surgical care reserved for children who have issues with antimicrobials or have clinically significant VUR that persists after several years of follow-up.

Vesicoureteral reflux is it important to find?

Vesico-ureteral reflux (VUR) has long been recognized as associated with urinary tract infections (UTIs), renal scarring, and chronic kidney disease (CKD). The concept of "reflux nephropathy" was born, whereby the VUR was considered the culprit, predisposing to recurrent UTIs and providing a conduit whereby the infection could ascend to the kidneys resulting in scarring and destruction. The more severe grades of reflux were thought to place the young child at particular risk of CKD. The question being asked in this pro/con debate is whether VUR is indeed the culprit responsible for a significant proportion of children with CKD, a number of whom progress to end-stage kidney failure (ESKF), and is thus important to find and treat, or is it an innocent bystander associated with CKD and ESKF but not the cause. We believe the latter and will present convincing evidence supported by large scale prospective randomized controlled trials that VUR is not the ogre it was thought to be and is not important to find following a UTI (with some exceptions).

Urinary tract infections in children

Urinary tract infections (UTIs) in children are among the most common bacterial infections in childhood. They are equally common in boys and girls during the first year of life and become more common in girls after the first year of life. Dividing UTIs into three categories; febrile upper UTI (acute pyelonephritis), lower UTI (cystitis), and asymptomatic bacteriuria, is useful for numerous reasons, mainly because it helps to understand the pathophysiology of the infection. A single episode of febrile UTI is often caused by a virulent Escherichia coli strain, whereas recurrent infections and asymptomatic bacteriuria commonly result from urinary tract malformations or bladder disturbances. Treatment of an upper UTI needs to be broad and last for 10 days, a lower UTI only needs to be treated for 3 days, often with a narrow-spectrum antibiotic, and asymptomatic bacteriuria is best left untreated. Investigations of atypical and recurrent episodes of febrile UTI should focus on urinary tract abnormalities, whereas in cases of cystitis and asymptomatic bacteriuria the focus should be on bladder function.

Renal scarring is the most significant predictor of breakthrough febrile urinary tract infection in patients with simplex and duplex primary vesico-ureteral reflux

INTRODUCTION

The association of high-grade vesico-ureteral reflux (VUR) with renal dysplasia and/or scarring is well-established, and the combination of these factors has been shown to decrease the likelihood of VUR resolution. Other VUR parameters have similarly been shown to be associated with VUR non-resolution, including VUR grade and timing at cystography, associated urinary tract anatomical abnormalities, and bladder dysfunction.

OBJECTIVE

To establish independent risk factors that can predict symptomatic persistence of VUR.

DESIGN

This was a single-centre study (2011-2017) including consecutive prospectively collected patients with primary VUR on voiding cystourethrogram (VCUG). Patients with dilating VUR also underwent renography (dimercaptosuccinic acid [DMSA] or 99m-technetium mercaptoacetyltriglycine [^99mTc-MAG3]). All patients were initially managed medically with antibiotic prophylaxis. Primary outcome was febrile culture-positive breakthrough urinary tract infection (BT-UTI). Demographic parameters, as well as VUR grade, VUR timing at cystography, presence of ureteral anomaly, VUR index (VURx), and differential renal function (DRF) or scarring were analysed to determine independent predictors.

RESULTS

A total of 61 patients (41 male, of whom 7 circumcised at presentation) were studied. VUR was diagnosed following investigation of prenatal hydronephrosis in 37 patients (62%) and following a febrile UTI in 22 (37%). Median [range] follow-up period was 38 [12-84] months. Data from a total of 77 refluxing renal units (RUs) were used for analysis. Analysis of VCUG data demonstrated that high VURx might be a potential significant predictor of breakthrough UTI (RR: 1.7, 95% CI: 1.1-2.7, p < 0.05 vs low VURx) but this was not the case for individual VURx components. Renography data showed increased risk of breakthrough UTI in patients with renal scarring (relative risk (RR): 5.1, 95% confidence interval (CI: 2.0-10.7, p < 0.0001 vs no renal scarring), but not in patients with reduced DRF. Multivariate regression analysis revealed that renal scarring was the only significant risk factor for breakthrough UTI. VUR patients with renal scarring were three times more likely to develop breakthrough UTI (odds ratio (OR): 3.3, 95% CI: 1.4-7.4, p < 0.01).

DISCUSSION

Multiple factors have been shown to be significant predictors of radiological VUR resolution. Univariate analysis of these factors suggests that only scarring on DMSA and VURx are significant predictors of symptomatic non-resolution. On multivariate analysis, scarring on DMSA was the only significant predictive variable. This information will be useful in targeting investigation and treatment in susceptible patients and when counselling families.

CONCLUSION

Renal scarring is the most significant risk factor for breakthrough UTI in primary VUR patients and could be used to determine those at risk of symptomatic VUR persistence.

First urinary tract infections in children: the role of the risk factors proposed by the Italian recommendations

AIM

In 2009, the Italian society for paediatric nephrology suggested the need for cystography, following a first febrile urinary tract infection (UTI), only in children at high risk for dilating vesicoureteral reflux or in the event of a second infection. The aim of this study was to evaluate the adequacy of the risk factors proposed by the Italian guidelines.

METHODS

Children aged 2-36 months, managed by 10 Italian hospitals between 2009 and 2013, with a first febrile UTI were retrospectively evaluated.

RESULTS

Four hundred and fourteen children were included: 51% female, mean age eight months. Escherichia coli was responsible of 84% UTIs. 269 children (65%) presented at least one risk factor, thus were further investigated: 44% had a reflux. The presence of a pathogen other than E. coli significantly predicted high-grade reflux, both in the univariate (Odd Ratio 2.52, 95% Confidence Interval 1.32-4.81, p < 0.005) and multivariate analysis (OR 2.74, 95% CI: 1.39-5.41, p: 0.003). 26/145 children (18%) with no risk factors experienced a second UTI, which prompted the execution of cystography, showing a dilating reflux in 11.

CONCLUSION

Among the risk factors proposed by the Italian guidelines, only the presence of a pathogen other than E. coli significantly predicted reflux. Cystography can be postponed in children with no risk factors.

Interventions for primary vesicoureteric reflux

BACKGROUND

Vesicoureteric reflux (VUR) results in urine passing retrograde up the ureter. Urinary tract infections (UTI) associated with VUR have been considered a cause of permanent renal parenchymal damage in children with VUR. Management has been directed at preventing UTI by antibiotic prophylaxis and/or surgical correction of VUR. This is an update of a review first published in 2004 and updated in 2007 and 2011.

OBJECTIVES

The aim of this review was to evaluate the available evidence for both benefits and harms of the currently available treatment options for primary VUR: operative, non-operative or no intervention.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 3 May 2018 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings, and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

RCTs in any language comparing any treatment of VUR and any combination of therapies.

DATA COLLECTION AND ANALYSIS

Two authors independently determined study eligibility, assessed quality and extracted data. Dichotomous outcomes were expressed as risk ratios (RR) with 95% confidence intervals (CI) and continuous data as mean differences (MD) with 95% CI. Data were pooled using the random effects model.

MAIN RESULTS

Thirty four studies involving 4001 children were included. Interventions included; long-term low-dose antibiotics, surgical reimplantation of ureters, endoscopic injection treatment, probiotics, cranberry products, circumcision, and oxybutynin. Interventions were used alone and in combinations. The quality of conduct and reporting of these studies was variable, with many studies omitting crucial methodological information used to assess the risk of bias. Only four of the 34 studies were considered at low risk of bias across all fields of study quality. The majority of studies had many areas of uncertainty in the risk of bias fields, reflecting missing detail rather than stated poor design.Low-dose antibiotic prophylaxis compared to no treatment/placebo may make little or no difference to the risk of repeat symptomatic UTI (9 studies, 1667 children: RR 0.77, 95% CI 0.54 to 1.09; low certainty evidence) and febrile UTI (RR 0.83, 95% CI 0.56 to 1.21; low certainty evidence) at one to two years. At one to three years, antibiotic prophylaxis made little or no difference to the risk of new or progressive renal damage on DMSA scan (8 studies, 1503 children: RR 0.73, 95% CI 0.33 to 1.61; low certainty evidence). Adverse events were reported in four studies with little or no difference between treatment groups (1056 children: RR 0.94, 95% CI 0.81 to 1.08; ), but antibiotics increased the likelihood of bacterial drug resistance threefold (187 UTIs: RR 2.97, 95% CI 1.54 to 5.74; moderate certainty evidence).Seven studies compared long-term antibiotic prophylaxis alone with surgical reimplantation of ureters plus antibiotics, but only two reported the outcome febrile UTI (429 children). Surgery plus antibiotic treatment may reduce the risk of repeat febrile UTI by 57% (RR 0.43, 95% CI 0.27 to 0.70; moderate certainty evidence). There was little or no difference in the risk of new kidney defects detected using intravenous pyelogram at 4 to 5 years (4 studies, 572 children, RR 1.09, 95% CI 0.79 to 1.49; moderate certainty evidence)Four studies compared endoscopic injection with antibiotics alone and three reported the outcome febrile UTI. This analysis showed little or no difference in the risk of febrile UTI with endoscopic injection compared to antibiotics (RR 0.74, 95% CI 0.31 to 1.78; low certainty evidence). Four studies involving 425 children compared two different materials for endoscopic injection under the ureters (polydimethylsiloxane (Macroplastique) versus dextranomer/hyaluronic acid polymer (Deflux), glutaraldehyde cross-linked (GAX) collagen (GAX) 35 versus GAX 65 and Deflux versus polyacrylate polyalcohol copolymer (VANTRIS)) but only one study (255 children, low certainty evidence) had the outcome of febrile UTI and it reported no difference between the materials. All four studies reported rates of resolution of VUR, and the two studies comparing Macroplastique with Deflux showed that Macroplastique was probably superior to dextranomer/hyaluronic acid polymer (3 months: RR 0.50, 95% CI 0.33 to 0.78; 12 months: RR 0.54 95% CI 0.35 to 0.83; low certainty evidence)Two studies compared probiotic treatment with antibiotics and showed little or no difference in risk of repeat symptomatic UTI (RR 0.82 95% CI 0.56 to 1.21; low certainty evidence)Single studies compared circumcision with antibiotics, cranberry products with no treatment, oxybutynin with placebo, two different surgical techniques and endoscopic injection with no treatment.

AUTHORS' CONCLUSIONS

Compared with no treatment, the use of long-term, low-dose antibiotics may make little or no difference to the number of repeat symptomatic and febrile UTIs in children with VUR (low certainty evidence). Considerable variation in the study designs and subsequent findings prevented drawing firm conclusions on efficacy of antibiotic treatment.The added benefit of surgical or endoscopic correction of VUR over antibiotic treatment alone remains unclear since few studies comparing the same treatment and with relevant clinical outcomes were available for analysis.

Congenital Disorders of the Human Urinary Tract: Recent Insights From Genetic and Molecular Studies

The urinary tract comprises the renal pelvis, the ureter, the urinary bladder, and the urethra. The tract acts as a functional unit, first propelling urine from the kidney to the bladder, then storing it at low pressure inside the bladder which intermittently and completely voids urine through the urethra. Congenital diseases of these structures can lead to a range of diseases sometimes associated with fetal losses or kidney failure in childhood and later in life. In some of these disorders, parts of the urinary tract are severely malformed. In other cases, the organs appear grossly intact yet they have functional deficits that compromise health. Human studies are beginning to indicate monogenic causes for some of these diseases. Here, the implicated genes can encode smooth muscle, neural or urothelial molecules, or transcription factors that regulate their expression. Furthermore, certain animal models are informative about how such molecules control the development and functional differentiation of the urinary tract. In future, novel therapies, including those based on gene transfer and stem cell technologies, may be used to treat these diseases to complement conventional pharmacological and surgical clinical therapies.

Long-Term (>10 Years) Results After Endoscopic Injection Therapy for Vesicoureteral Reflux

OBJECTIVE

Endoscopic injection is an accepted alternative for the treatment of vesicoureteral reflux (VUR) with the most commonly used agent being dextranomer/hyaluronic acid (Dx/HA). There are few reports on very long-term results after this treatment, although the biodegradable nature of the product could indicate that results might deteriorate on the long term. We, therefore, decided to evaluate the efficacy of Dx/HA copolymer endoscopic injection, in terms of recurrence of febrile urinary tract infections (fUTIs) in children, with a follow-up of at least 10 years.

MATERIALS AND METHODS

We analyzed the medical data of all children who were diagnosed with VUR and underwent endoscopic injection with >10 years follow-up, in two University Hospitals. We reviewed their medical files and then contacted patients by phone.

RESULTS

We found 68 patients who had undergone endoscopic treatment of VUR with a follow-up of minimum 10 years. We were able to contact 53 of these patients of whom 38 were girls, and 36 had bilateral VUR with a total of 89 ureteral units. Mean age at surgery was 86 months (26-136). Mean follow-up was 12.5 years (range: 10.5-15). No child presented postinjection obstruction. Thirteen patients presented with a recurrence of fUTI during the postoperative course of whom 8 presented persistent VUR. All recurrences of fUTI occurred within the first 5 years of follow-up. Four underwent a second injection and 4 underwent open reimplantation. Success rate per patient was 85%.

CONCLUSION

Results of endoscopic injection using Dx/HA remain stable over time (>10 years). In our series, recurrences of fUTI occur within the first 5 years of follow-up.

Genome-wide linkage and association study implicates the 10q26 region as a major genetic contributor to primary nonsyndromic vesicoureteric reflux

Vesicoureteric reflux (VUR) is the commonest urological anomaly in children. Despite treatment improvements, associated renal lesions – congenital dysplasia, acquired scarring or both – are a common cause of childhood hypertension and renal failure. Primary VUR is familial, with transmission rate and sibling risk both approaching 50%, and appears highly genetically heterogeneous. It is often associated with other developmental anomalies of the urinary tract, emphasising its etiology as a disorder of urogenital tract development. We conducted a genome-wide linkage and association study in three European populations to search for loci predisposing to VUR. Family-based association analysis of 1098 parent-affected-child trios and case/control association analysis of 1147 cases and 3789 controls did not reveal any compelling associations, but parametric linkage analysis of 460 families (1062 affected individuals) under a dominant model identified a single region, on 10q26, that showed strong linkage (HLOD = 4.90; ZLRLOD = 4.39) to VUR. The ~9Mb region contains 69 genes, including some good biological candidates. Resequencing this region in selected individuals did not clearly implicate any gene but FOXI2, FANK1 and GLRX3 remain candidates for further investigation. This, the largest genetic study of VUR to date, highlights the 10q26 region as a major genetic contributor to VUR in European populations.

Controversies Regarding Management of Vesico-ureteric Reflux

The primary goal in the management of a child with urinary tract infection (UTI) is to prevent recurrence of UTI and acquired renal damage. Approximately 15% of children develop renal scarring after a first episode of febrile UTI. Vesico-ureteric reflux (VUR) is diagnosed in 30-40% of children imaged after first febrile UTI. The 'top-down' approach involving ultrasound and dimercaptosuccinic acid scan (DMSA) first after an appropriate interval following UTI, can help in avoiding voiding cystourethrogram (VCUG), an invasive test with higher radiation exposure. The majority view remains that VCUG should be done after the second attack of UTI in girls and first attack of UTI in boys. Although the evidence in favour of antibiotic prophylaxis remains doubtful in preventing renal scars associated with VUR, it remains the first line treatment for high-grade reflux (grade 3-5) with an aim to prevent UTI and allow spontaneous resolution of VUR. Early identification and appropriate treatment of associated bowel bladder dysfunction is an essential part of successful medical management of VUR. Endoscopic treatment of VUR, using a bulking agent, is useful in grade 3 VUR. The main controversy regarding intervention (endoscopic/open surgical intervention) involves absence of strong evidence for these interventions in reducing renal scarring on randomized controlled trials. However, several recent trials have found the surgical interventions to be effective in reducing recurrent pyelonephritis and repeated hospital admissions.

Imaging studies and biomarkers to detect clinically meaningful vesicoureteral reflux

The work-up of a febrile urinary tract infection is generally performed to detect vesicoureteral reflux (VUR) and its possible complications. The imaging modalities most commonly used for this purpose are renal-bladder ultrasound, voiding cystourethrogram and dimercapto-succinic acid scan. These studies each contribute valuable information, but carry individual benefits and limitations that may impact their efficacy. Biochemical markers are not commonly used in pediatric urology to diagnose or differentiate high-risk disease, but this is the emerging frontier, which will hopefully change our approach to VUR in the future. As it becomes more apparent that there is tremendous clinical variation within grades of VUR, the need to distinguish clinically significant from insignificant disease grows. The unfortunate truth about VUR is that recommendations for treatment may be inconsistent. Nuances in clinical decision-making will always exist, but opinions for medical versus surgical intervention should be more standardized, based on risk of injury to the kidney.

Vesicoureteral reflux and the extracellular matrix connection

Primary vesicoureteral reflux (VUR) is a common pediatric condition due to a developmental defect in the ureterovesical junction. The prevalence of VUR among individuals with connective tissue disorders, as well as the importance of the ureter and bladder wall musculature for the anti-reflux mechanism, suggest that defects in the extracellular matrix (ECM) within the ureterovesical junction may result in VUR. This review will discuss the function of the smooth muscle and its supporting ECM microenvironment with respect to VUR, and explore the association of VUR with mutations in ECM-related genes.

Predicting long-term renal damage in children with vesicoureteral reflux under conservative initial management: 205 cases in a tertiary referral center

INTRODUCTION

Vesicoureteral reflux (VUR) is one of the most common ailments in children. Evidence-based guidelines recommend conservative treatment in children with VUR, followed by endoscopic surgery in those with breakthrough febrile urinary tract infections (UTIs). Despite this fact, the management of VUR is still controversial. Our objective is to evaluate the conservative strategy in children with primary VUR in terms of renal function and scarring, and identify factors associated with poor prognosis in those children.

MATERIAL AND METHODS

A retrospective study was carried out in a tertiary center in children with primary VUR under conservative strategy treatment from 1989 to 2015. Data extracted included age of presentation, family and prenatal backgrounds, radiographic evaluation including ultrasound (US), dimercaptosuccinic acid (DMSA) scans and voiding cystourethrogram (VCUG). The SPSS program was used for statistical analysis.

RESULTS

Two-hundred and five patients were diagnosed and followed a conservative therapy scheme (49.8% males, 50.2% females) after febrile UTI (73.17%) or prenatal diagnosis (26.83%). VCUG showed 53.20% of low-moderate VUR grade, 46.80% high VUR grade. Renal damage was present at diagnosis in 40.89%. Mean follow-up reakthrough recurrent febrile UTIs and underwent surgery. Conservative therapy was followed in 189 patients. Renal scarring or decreased kidney function were shown in 15.12% respectively. Renal damage was identified as a risk factor for poor prognosis (p-value <0.005) only for renal function deterioration. Patients with high-grade VUR required surgery in a significantly greater proportion (p <0.005) due to recurrent febrile UTIs.

CONCLUSIONS

Conservative strategy is a feasible treatment for primary VUR in children. The majority of cases could be managed conservatively with good outcomes after long-term follow-up. Decreased renal function is more frequent in patients with high-grade VUR. Renal damage at diagnosis increases the risk for surgical treatment.

Inflammation drives renal scarring in experimental pyelonephritis

Acquired renal scarring occurs in a subset of patients following febrile urinary tract infections and is associated with hypertension, proteinuria, and chronic kidney disease. Limited knowledge of histopathology, immune cell recruitment, and gene expression changes during pyelonephritis restricts the development of therapies to limit renal scarring. Here, we address this knowledge gap using immunocompetent mice with vesicoureteral reflux. Transurethral inoculation of uropathogenic Escherichia coli in C3H/HeOuJ mice leads to renal mucosal injury, tubulointerstitial nephritis, and cortical fibrosis. The extent of fibrosis correlates most significantly with inflammation at 7 and 28 days postinfection. The recruitment of neutrophils and inflammatory macrophages to infected kidneys is proportional to renal bacterial burden. Transcriptome analysis reveals molecular signatures associated with renal ischemia-reperfusion injury, immune cell chemotaxis, and leukocyte activation. This murine model recapitulates the cardinal histopathological features observed in humans with acquired renal scarring following pyelonephritis. The integration of histopathology, quantification of cellular immune influx, and unbiased transcriptional profiling begins to define potential mechanisms of tissue injury during pyelonephritis in the context of an intact immune response. The clear relationship between inflammatory cell recruitment and fibrosis supports the hypothesis that acquired renal scarring arises as a consequence of excessive host inflammation and suggests that immunomodulatory therapies should be investigated to reduce renal scarring in patients with pyelonephritis.

Acute pyelonephritis in children

Acute pyelonephritis is one of the most serious bacterial illnesses during childhood. Escherichia coli is responsible in most cases, however other organisms including Klebsiella, Enterococcus, Enterobacter, Proteus, and Pseudomonas species are being more frequently isolated. In infants, who are at major risk of complications such as sepsis and meningitis, symptoms are ambiguous and fever is not always useful in identifying those at high risk. A diagnosis of acute pyelonephritis is initially made on the basis of urinalysis; dipstick tests for nitrites and/or leukocyte esterase are the most accurate indicators of infection. Collecting a viable urine sample for urine culture using clean voided methods is feasible, even in young children. No gold standard antibiotic treatment exists. In children appearing well, oral therapy and outpatient care is possible. New guidelines suggest less aggressive imaging strategies after a first infection, reducing radiation exposure and costs. The efficacy of antibiotic prophylaxis in preventing recurrence is still a matter of debate and the risk of antibiotic resistance is a warning against its widespread use. Well-performed randomized controlled trials are required in order to better define both the imaging strategies and medical options aimed at preserving long-term renal function.

Vesicoureteral Reflux and Antibiotic Prophylaxis: Why Cohorts and Methodologies Matter

PURPOSE

Published cohorts of children with vesicoureteral reflux placed on antibiotic prophylaxis differ in baseline characteristics and methodology. These data have been combined in meta-analyses to derive treatment recommendations. We analyzed these cohorts in an attempt to understand the disparate outcomes reported.

MATERIALS AND METHODS

A total of 18 studies were identified from 1987 to 2013. These series retrospectively or prospectively evaluated children with vesicoureteral reflux who were on long-term antibiotic prophylaxis. Presenting demographic data, criteria and methods of evaluation were tabulated. Outcomes were compared, specifically recurrent urinary infections and renal scarring.

RESULTS

Significant differences identified in baseline characteristics included gender, circumcision status and reflux grade, and differences in methodology included evaluation of bowel and bladder dysfunction, method of urine collection, definition of urinary infection, measurement of compliance and means of identifying renal scarring. Cohorts with larger numbers of uncircumcised boys had more breakthrough urinary infections. Infection and renal scarring rates were higher in series with higher grades of reflux. Bagged urine specimens were allowed in 6 series, rendering the data suspect. Children with bowel and bladder dysfunction were excluded from 3 cohorts, and bowel and bladder dysfunction was correlated with outcome in only 1 cohort. Compliance was monitored in only 6 studies.

CONCLUSIONS

Subpopulations and methodologies vary significantly in published series of children with vesicoureteral reflux on antibiotic prophylaxis. It is inappropriate to combine outcomes data from these series in a meta-analysis, which would serve to blur distinctions between these subpopulations. Broad recommendations or guidelines based on meta-analyses should be viewed with caution.

The Association between Vitamin D Levels and Urinary Tract Infection in Children

AIM

We aimed to examine whether there is any association between serum levels of 25-hydroxyvitamin D [25(OH)D3] and urinary tract infection (UTI) among children.

METHODS

White blood cell count, serum C-reactive protein, calcium, phosphorus, alkaline phosphatase, parathormone, and serum 25(OH)D3 levels were measured in 82 children experiencing a first episode of UTI, with no risk factors for UTI, and 64 healthy control children.

RESULTS

The mean serum levels of 25(OH)D3 among children with UTI were significantly lower than those of controls (11.7 ± 3.3 vs. 27.6 ± 4.7 ng/ml; p < 0.001). The serum levels of 25(OH)D3 were significantly lower in patients with acute pyelonephritis compared to patients with lower UTI (8.6 ± 2.8 vs. 14.2 ± 3.0 ng/ml; p < 0.001). Within the study group, mean serum levels of 25(OH)D3 among girls were lower than those of boys (10.9 ± 3.4 ng/ml vs. 13.2 ± 4.4 ng/ml; p < 0.001). Multivariate analysis showed that a serum 25(OH)D3 level of <20 ng/ml (odds ratio 3.503, 95% confidence interval 1.621-7.571; p = 0.001) was associated with UTI in children.

CONCLUSIONS

Our results suggest that vitamin D deficiency may be a risk factor for UTI in children.

Urinary microprotein concentrations in the long-term follow-up of dilating vesicoureteral reflux patients who underwent medical or surgical treatment

PURPOSE

This study examined the relationship between urinary microprotein concentrations and renal functional parameters in children with dilating (grade III-V) vesicoureteral reflux (VUR) who underwent either medical or surgical treatment.

METHODS

All 44 dilating VUR patients who were followed for 4 years were screened for inclusion in this study. The patients' clinical features and clinical outcomes, as well as the urinary activities of albumin (ALB), transferrin (TRF), immunoglobulin G (IgG), alpha-1-microglobulin (α1-MG), and N-acetyl-β-glucosaminidase (NAG), were retrospectively analyzed.

RESULTS

High values of NAG, α1-MG, IgG, TRF, and ALB were noted in 73.33, 58.33, 43.33, 24.14, and 53.33 % of patients, respectively, at the first examination. Cystatin C, eGFR, and urinary microprotein levels were associated with a good prognosis after 4 years of follow-up. No differences in recurrent UTI, cystatin C concentration, most microprotein/creatinine (Cr) ratios, eGFR, or ΔGFR4 % were found between the groups. High levels of urinary proteins were found in 2.38-9.52 % of cases after 4 years of follow-up. ALB/Cr, IgG/Cr, and α1-MG/Cr levels were positively correlated with 99mTc-dimercaptosuccinic acid (DMSA) grade, and α1-MG excretion was inversely correlated with eGFR.

CONCLUSIONS

The levels of microprotein were elevated at diagnosis in a higher proportion of patients than for the other markers examined. At long-term follow-up, the reflux level had decreased or completely resolved in all patients, and the proportions of microproteins that were elevated were significantly reduced. Renal impairment measured by eGFR and DMSA grade was related to increased urinary α1-MG levels.

Renal tract abnormalities missed in a historical cohort of young children with UTI if the NICE and AAP imaging guidelines were applied

OBJECTIVE

In a historical cohort of children with a urinary tract infection (UTI) who had already undergone all the imaging procedures, the aim was to determine renal tract abnormalities which would have been missed had we implemented the new guidelines from the National Institute for Health and Care Excellence in the United Kingdom (NICE) or the American Academy of Pediatrics (AAP).

MATERIAL AND METHODS

After a UTI episode, forty-three children (28 females, 65%) aged between 2 months and 2 years presenting at two general hospitals with a febrile UTI before 2008 underwent all the recommended imaging studies predating the new guidelines. Hydronephrosis was defined and graded according to the Society for Fetal Urology (SFU) classification. Hydronephrosis grade II (mild pelvicalyceal dilatation), grade III (moderate dilatation), and grade IV (gross dilatation with thinning of the renal cortex), duplication, vesicoureteral reflux (VUR) grade II and above, renal scarring and reduced renal uptake (<45%) on technetium-99m-labeled dimercaptosuccinic acid (DMSA) scintigraphy were considered significant abnormalities. We calculated the proportion of abnormalities which would have been missed had the new guidelines been used instead.

RESULTS

The median of age was 7.6 months (mean 8.7, range 2-24 months), with the majority (n = 37, 86%) being under 1 year of age. Ultrasound (US) showed hydronephrosis in 14 (32%), all grade II. A voiding cystourethrogram (VCUG) was performed in all and showed VUR ≥ grade II in 16 (37%), including eight children (19%) where it was bilateral. DMSA scan showed scarring in 25 children (58%) of whom 11 (26%) had bilateral scars. Reduced differential renal uptake was present in 10 children (23%). Of the 29 children with normal US, 18 (62%) had renal scarring and nine (31%) had VUR ≥ grade II. The NICE guidelines would have missed 63% of the children with VUR ≥ grade II, including a high proportion of grades IV and V VUR, 44% of the children with renal scarring, and 20% of the children with decreased renal uptake, including some children with bilateral renal scarring and with decreased renal uptake. The AAP guidelines would have missed 56% of the children with VUR ≥ grade II, including a high proportion of grades IV and V VUR, and all children with renal scarring as well as those with decreased renal uptake.

CONCLUSION

The prevalence of renal tract abnormalities missed by the new guidelines is high. They should be used with full awareness of their limitations.

Vesicoureteric reflux in children

Vesicoureteric reflux is defined as the retrograde passage of urine from the bladder into one or both ureters and often up to the kidneys, and mainly affects babies and infants. In severe cases dilatation of the ureter, renal pelvis, and calyces might be seen. Traditionally it was thought that only a low percentage of children have vesicoureteric reflux, but studies have suggested as many as 25-40% are affected. Guidelines recommend that the number of investigations for vesicoureteric reflux in children who have had a febrile urinary tract infection be reduced, but this approach is controversial. The recommendations also suggest that prophylactic antibiotics and surgery should be avoided in children with non-severe vesicoureteric reflux. In this Seminar I present data on the management of children with vesicoureteric reflux and give suggestions on how to navigate this difficult area.

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.

Antimicrobial prophylaxis for children with vesicoureteral reflux

BACKGROUND

Children with febrile urinary tract infection commonly have vesicoureteral reflux. Because trial results have been limited and inconsistent, the use of antimicrobial prophylaxis to prevent recurrences in children with reflux remains controversial.

METHODS

In this 2-year, multisite, randomized, placebo-controlled trial involving 607 children with vesicoureteral reflux that was diagnosed after a first or second febrile or symptomatic urinary tract infection, we evaluated the efficacy of trimethoprim-sulfamethoxazole prophylaxis in preventing recurrences (primary outcome). Secondary outcomes were renal scarring, treatment failure (a composite of recurrences and scarring), and antimicrobial resistance.

RESULTS

Recurrent urinary tract infection developed in 39 of 302 children who received prophylaxis as compared with 72 of 305 children who received placebo (relative risk, 0.55; 95% confidence interval [CI], 0.38 to 0.78). Prophylaxis reduced the risk of recurrences by 50% (hazard ratio, 0.50; 95% CI, 0.34 to 0.74) and was particularly effective in children whose index infection was febrile (hazard ratio, 0.41; 95% CI, 0.26 to 0.64) and in those with baseline bladder and bowel dysfunction (hazard ratio, 0.21; 95% CI, 0.08 to 0.58). The occurrence of renal scarring did not differ significantly between the prophylaxis and placebo groups (11.9% and 10.2%, respectively). Among 87 children with a first recurrence caused by Escherichia coli, the proportion of isolates that were resistant to trimethoprim-sulfamethoxazole was 63% in the prophylaxis group and 19% in the placebo group.

CONCLUSIONS

Among children with vesicoureteral reflux after urinary tract infection, antimicrobial prophylaxis was associated with a substantially reduced risk of recurrence but not of renal scarring. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; RIVUR ClinicalTrials.gov number, NCT00405704.).

Renal cortical abnormalities in siblings of index patients with vesicoureteral reflux

OBJECTIVE

Screening siblings of index patients with vesicoureteral reflux (VUR) has been proposed to identify children who are at risk for renal damage. However, screening siblings for VUR remains controversial. We investigated the prevalence of VUR and renal cortical abnormalities in the sibling population in a large cohort of families with VUR.

METHODS

Between 1998 and 2012, parents of index patients with grade III to V VUR were asked permission to screen siblings <6 years of age for VUR. Siblings were divided into 2 groups: siblings with a documented history of a previous urinary tract infection (UTI) and siblings who were screened for VUR and never had a UTI. A logistic regression model was used to determine independent risk factors associated with renal cortical abnormalities such as history of presentation, age, gender, and grade of VUR.

RESULTS

There were 318 siblings in 275 families in the study. VUR was found after screening in 190 (60%) siblings and after a UTI in 128 (40%). Multivariate analysis revealed that siblings who had a previous UTI (odds ratio: 3.38), siblings with high grade reflux (odds ratio: 3.62), and siblings over 1 year of age (odds ratio: 2.84) were the most significant independent risk factors associated with renal cortical abnormalities.

CONCLUSIONS

There is increased risk of renal cortical abnormalities in siblings with a previous UTI, siblings with high-grade VUR, and siblings over age 1 year. This information may help to counsel parents about the risk of VUR and reflux nephropathy in familial VUR.

Endoscopic treatment of vesico-ureteral reflux: Experience of 99 ureteric moieties

Aims:

To study the outcome of endoscopic hyaluronic acid/dextranomer injection in patients with vesico-ureteric reflux (VUR).

Materials and Methods:

Sixty-three children were evaluated with a median follow up of 18 months (12-55 months) before injecting hyaluronic acid/dextranomer in a total of 99 ureteric moieties. Median age at presentation was 24 months (6-72 months). Primary VUR was the main presenting diagnosis in 60%. Patients were monitored for urinary tract infection (UTI), glomerular filtration rate (GFR), renal scarring, persistence, or appearance of contra-lateral reflux.

Results:

Grade III VUR was the most common (38%) followed by Grade IV (24%), Grade V (17%), Grade II (14%), and Grade I (7%). Most common cause for VUR was Primary (60%), followed by posterior urethral valve (PUV) (19%), bladder exstrophy (5%), anorectal malformation (ARM), epispadias, and duplex system. Analysis of patients characteristics at presentation revealed renal scarring (40%), split renal functions <35% (35%), recurrent UTI (15%), GFR <50 ml/min/1.73 m² (15%), serum creatinine >1.4 mg/dL (10%). Complete resolution (100%) of Grade I and Grade II VUR was achieved after single injection. For Grade III VUR, single injection resolved reflux in 85.5% ureters, 100% resolution was seen after 2^nd injection. In Grade IV VUR, 1^st injection resolved VUR in 83.3% ureters, 95.8% ureters were reflux free after 2^nd injection, and 100% resolution was seen after 3^rd injection. In Grade V VUR, 94% ureters showed absent reflux after three injections.

Conclusion:

Hyaluronic acid/dextranomer injection holds promise even in higher grades of VUR.

Plasma renin activity: An early marker of progressive renal disease in posterior urethral valves

Introduction:

A significant number of children with posterior urethral valves (PUV) develop chronic renal failure (CRF) due to activation of the renin angiotensin system (RAS). We investigated the role of plasma renin activity (PRA) in these cases and sought to establish a relationship between the accepted criteria of renal damage and PRA.

Aims and Objectives:

The aim of this study is to establish the relationship between PRA and CRF.

Materials and Methods:

The records of 250 patients with PUV were reviewed. Multiple linear regression analysis was used to assess correlations between PRA, grade of reflux, presence of scars and raised creatinine and decrease in glomerular filtration rates (GFR). A P < 0.5 was considered as significant.

Results:

A total of 58 patients were included. Their mean age was 16 years, range 5.3-24.2 years, mean follow-up period was 12.6 ± 3.6 years. At diagnosis, 22/58 (38%) patients were in CRF and 36/58 (62%) patients had normal renal function (RF). The mean PRA after treatment was higher in those who developed CRF than in those with normal RF (12.6 ± 10.2 vs. 34.6 ± 14.2 ng/ml/24 h, P = 0.02). Mean GFR at 1 year of age were 48 ± 9.8 ml/min/1.73 m² and 86 ± 12.5 ml/min/1.73 m² respectively (P = 0.005). PRA correlated negatively with GFR, t = –2.816,

Confidence Interval:

P = 0. 007. In the temporal plot over a period of 14 years, a rise in PRA preceded the fall in GFR in patients who developed CRF.

Conclusions:

This study shows that RAS is activated earlier in kidneys susceptible to damage. PRA could be investigated as a marker for the early detection and prevention of ongoing renal damage.

Controversy in urinary tract infection management in children: a review of new data and subsequent changes in guidelines

Controversy and lack of consensus have been encountered in the management of pediatric urinary tract infection (UTI), including its diagnosis, radiological investigations and the use of antibiotic therapy. In this review, we discuss the need for radiological investigations and the extent of their use as well as the need for prophylactic antibiotics in children with UTI and vesicoureteral reflux. Only a small proportion of children with first UTI and no history of antenatal renal abnormalities have clinically important malformations. Renal ultrasound should be performed in febrile infants and young children with UTI; a micturating cystourethrogram should not be performed routinely after the first febrile UTI. Long-term antibiotics appear to reduce the risk of recurrent symptomatic UTI in susceptible children, although the clinical benefit is marginal. Current recommendations encourage performing radiological investigations only in children at risk and discourage routine prophylactic antibiotic use.

Does the ureteric jet Doppler waveform have a role in detecting vesicoureteric reflux?

Data reported in this issue of Pediatric Nephrology suggest that the ureteric jet Doppler waveform can predict the occurrence of vesicoureteric reflux (VUR). Many different methods are currently used to detect VUR, including traditional X-ray micturating cystourethrogram, indirect and direct nuclear imaging and contrast enhanced ultrasonography. These methods are invasive, do have some radiation burden and are also quite uncomfortable to paediatric patients. This relatively new non-invasive method is therefore of interest, but its efficacy needs to be confirmed in further studies and, in particular, in babies and infants before it can possibly be considered as a good method to provide clinical information on VUR. Once such studies have been performed, this method may also prove to be a useful approach to obtain modern knowledge on the occurrence of VUR in healthy children.

The incidence of urinary tract infection after open anti-reflux surgery for primary vesicoureteral reflux: early and long-term follow up

OBJECTIVES

Controversy exists regarding the benefit of open anti-reflux surgery (OS) in reducing the incidence of urinary tract infection (UTI). We, therefore, reviewed our short and long term data in children who have undergone OS.

METHODS

153 children (131F, 22M; ages 2-16 yrs, mean 8 yrs) underwent OS from 1990 to 2008. Reasons for presentation were UTI-131; sibling survey-19; prenatal hydronephrosis-3. Major reasons for OS were: breakthrough UTI-74 (48%), high grade (IV or V)-49 (32%), poor compliance with prophylaxis-15 (10%). Of 153 pre-operative DMSA scans, 60 (39%) had defects. Post-operative studies were performed 6 months after surgery and 151 (99%) had negative voiding cystourethrograms (VCUG's). All underwent urine cultures 6 months post-op and prophylaxis was stopped. 56 (37%) were later contacted at an average 7 yrs post-op (range: 2-13 yrs).

RESULTS

23 (15% of 153 followed short term, 40% of 56 followed long term)-20F, 3M-had non-febrile UTI's (nfUTI's) and one girl (0.6%) had a febrile UTI (fUTI). Of those who had nfUTI's 7 (30%) had high grade reflux and 16 (70%) had pre-op breakthrough UTI's. 11 (48%) had DMSA scans with defects. 2 had UTI's within 1 year after a negative VCUG and 21 had UTI's later (1-8 yrs). 1 girl had a fUTI 1 month after a negative VCUG.

CONCLUSIONS

Successful OS effectively eliminates fUTI. Families should be counseled that nfUTI may occur many years after surgery, especially in girls with a history of breakthrough UTI and renal scarring.

Update on recent guidelines for the management of urinary tract infections in children: the shifting paradigm

PURPOSE OF REVIEW

Recent guidelines on the management of urinary tract infections (UTIs) in children have seen a shift from aggressive imaging studies and the use of prophylactic antibiotics to a more restrictive and targeted approach. This review focuses on new additions to the literature on management of UTI from January 2011 to September 2012.

RECENT FINDINGS

The causal relationship between UTI-vesicoureteral reflux (VUR) and renal scarring has been challenged by several studies. Concerns about unnecessary exposure to ionizing radiation, invasiveness of some of the procedures, and risk of infection have also been raised. With improved prenatal ultrasound, a 'top-down' approach to investigating febrile UTI in children using renal bladder ultrasound alone as an initial study has become popular. Several studies have reported that prophylactic antibiotics and imaging studies after first UTI can be reduced substantially without affecting the risk of recurrent UTI or renal scarring.

SUMMARY

The use of targeted imaging approach in evaluating febrile UTI in children may lead to improved resource use and reduction of potential harmful procedures and interventions, without affecting outcomes of UTI in children. Providers using current guidelines should endeavor to collect practice-based evidence to validate and inform future guidelines.

Prevalence and predictors of renal functional abnormalities of high grade vesicoureteral reflux

PURPOSE

The association of vesicoureteral reflux, febrile urinary tract infections and renal parenchymal damage is well recognized. We determined the prevalence and predictors of renal functional abnormalities in children with high grade vesicoureteral reflux.

MATERIALS AND METHODS

We retrospectively reviewed the medical records and dimercapto-succinic acid scans of 774 consecutive children with primary high grade vesicoureteral reflux (grade IV-V) seen at our institution between 1998 and 2011. For multivariate analysis we analyzed variables associated with renal functional abnormalities, such as presentation history, age, gender and reflux grade, in a logistic regression model.

RESULTS

Of the children 698 (90%) and 76 (10%) had grade IV and V reflux, respectively. Dimercapto-succinic acid scans revealed renal functional abnormalities in 291 children (37.6%), including 240 (34%) with grade IV and 51 (67%) with grade V reflux. Univariate analysis showed that age greater than 1 year (OR 2.95, p <0.001), grade V reflux (OR 4.09, p <0.001) and preoperative bladder/bowel dysfunction (OR 2.94, p = 0.026) were significant predictors of renal functional abnormalities. Multivariate analysis showed that age greater than 1 year (OR 3.45, p = 0.001) and grade V reflux (OR 5.89, p <0.001) were the most significant independent predictors of such abnormalities.

CONCLUSIONS

There is an increased risk of renal functional abnormalities in children older than 1 year and those with grade V vesicoureteral reflux. Patients with a history of bladder/bowel dysfunction are also at greater risk for such abnormalities. The early detection and treatment of high grade vesicoureteral reflux may prevent acquired renal parenchymal damage and limit the progression of renal damage in patients with congenital reflux nephropathy.

Pediatric urinary tract infection: does the evidence support aggressively pursuing the diagnosis?

The epidemiology of pediatric fever has changed considerably during the past 2 decades with the development of vaccines against the most common bacterial pathogens causing bacteremia and meningitis. The decreasing incidence of these 2 conditions among vaccinated children has led to an emphasis on urinary tract infection as a remaining source of potentially hidden infections in febrile children. Emerging literature, however, has led to questions about both the degree and nature of the danger posed by urinary tract infection in nonverbal children, whereas the aggressive pursuit of the diagnosis consumes resources and leads to patient discomfort, medical risks, and potential overdiagnosis. We review both early and emerging literature to examine the utility and efficacy of early identification and treatment of urinary tract infection in children younger than 24 months. We conclude that in well children of this age, it may be reasonable to withhold or delay testing for urinary tract infection if signs of other sources are apparent or if the fever has been present for fewer than 4 to 5 days.

[Primary vesicoureteral reflux]

The never ending discussion about the diagnostics and treatment of vesicoureteral reflux (VUR) now includes arguments for diagnostic nihilism as well as invasive diagnostics and therapy, which is reminiscent of the debate on prostate cancer in adulthood. The common goal of all currently competing diagnostic strategies and approaches is the prevention of renal scars by the most effective and least burdensome approach. There is a difference between acquired pyelonephritic scars with VUR (acquired reflux nephropathy) and congenital reflux nephropathy (primary dysplasia) which cannot be influenced by any therapy.The VUR can be verified by conventional radiological voiding cystourethrography (VCUG), by urosonography, radionuclide cystography or even by magnetic resonance imaging (MRI). The guidelines of the European Association of Urology/European Society for Paediatric Urology (EAU/ESPU) recommend radiological screening for VUR after the first febrile urinary tract infection. Significant risk factors in patients with VUR are recurrent urinary tract infections (UTI) and parenchymal scarring and the patients should undergo patient and risk-adapted therapy. Infants with dilating reflux have a higher risk of renal scarring than those without dilatation of the renal pelvis. Bladder dysfunction or dysfunctional elimination syndrome represents a well-known but previously neglected risk factor in combination with VUR and should be treated prior to any surgical intervention as far as is possible.Certainly not every patient with VUR needs therapy. The current treatment strategies take into account age and gender, the presence of dysplastic or pyelonephritic renal scars, the clinical symptoms, bladder dysfunction and frequency and severity of recurrent UTI as criteria for the therapy decision. The use of an antibacterial prophylaxis as well as the duration is controversially discussed. Endoscopic therapy can be a good alternative to antibacterial prophylaxis or a surveillance strategy in patients with low grade VUR. In patients with dilating VUR and given indications for surgery, endoscopic treatment can be offered. However, parents should be completely informed about the significantly lower success rate of endoscopic therapy compared to open surgical procedures. The open surgical techniques guarantee the highest success rates and should be used in patients with a dilating VUR and high risk of renal damage.

Febrile urinary tract infections after ureteroneocystostomy and subureteral injection of dextranomer/hyaluronic acid for vesicoureteral reflux--do choice of procedure and success matter?

PURPOSE

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.

MATERIALS AND METHODS

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.

RESULTS

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).

CONCLUSIONS

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

PURPOSE

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.

MATERIALS AND METHODS

Digital images were reviewed. Responses were compared and discrepancies adjudicated by teleconference to a final assessment.

RESULTS

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).

CONCLUSIONS

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.

Long-term clinical consequences of urinary tract infections during childhood: a review

Kidney scarring related to urinary tract infection in childhood has been considered the cause of serious long-term clinical consequences. This assumption is now debated, as the advent of routine antenatal ultrasound in the 1980s has shown that a consistent part of the changes previously attributed to postinfectious scarring is mainly due to congenital malformations. With the aim of determining what is presently known on the long-term clinical consequences of urinary tract infections (UTIs) in childhood, we performed a review of the literature on the relation between UTIs and blood pressure, renal function, growth and pregnancy-related complications. By searching Medline/PubMed and Embase from 1980 to 2011, we identified 20 cohorts of children from 23 papers.

CONCLUSIONS

  Renal function: there are no clear data to establish long-term consequences following UTIs during childhood. Most data seem to show that the outcome of renal function can already be delineated at first presentation or in the initial years of follow-up; only 0.4% of children with normal renal function at start presented a decrease during follow-up. Hypertension: there is a low risk, associated with renal damage. Growth and pregnancy-related complications: the few available data seem to exclude a major influence of UTIs.

Intraureteral injection of NASHA/Dx gel under direct ureteroscopic visualization for the treatment of primary high-grade vesicoureteral reflux

OBJECTIVE

To present a preliminary experience with the modified technique of extravesical intraureteral injection of non-animal-stabilized hyaluronic acid/dextranomer (NASHA/Dx) gel under direct ureteroscopic visualization for the treatment of primary high-grade vesicoureteral reflux (VUR).

PATIENTS AND METHODS

The medical records of all pediatric patients (age range, 0-14 years) who underwent intraureteral injection of NASHA/Dx gel under direct ureteroscopic visualization for the treatment of primary high-grade VUR during the period June 2006-June 2010 were reviewed.

RESULTS

Eighty-nine children (61 boys, 28 girls; M:F ratio, 2.1) underwent intraureteral injection of NASHA/Dx gel under direct ureteroscopic visualization for the treatment of primary high-grade VUR during the study period. VUR completely disappeared after the injection of NASHA/Dx gel into 105 (73%) of 144 ureters, with no further treatment required. Thirty-five (24.3%) required a second injection, and 2 (1.4%) required a third injection for resolution of their VUR. No intraoperative complications were observed. No ureteral obstruction during follow-up was observed using ultrasound or micturition studies.

CONCLUSIONS

Intraureteral injection of NASHA/Dx gel under direct ureteroscopic visualization is safe and effective in the treatment of primary high-grade VUR, including cases with ureteral duplication, if the ureteral meatus is easy to pass through without mechanical dilation. This approach represents an effective and safe alternative to antibiotic prophylaxis alone and open surgery.

Familial vesicoureteral reflux and reflux related morbidity in relatives of index patients with high grade vesicoureteral reflux

PURPOSE

The familial nature of vesicoureteral reflux is well recognized. However, there is little information about the prevalence of vesicoureteral reflux and reflux related morbidity in the relatives of index patients with vesicoureteral reflux. Therefore, we determined the prevalence of vesicoureteral reflux and reflux related morbidity in first, second and third-degree relatives of index patients with high grade vesicoureteral reflux.

MATERIALS AND METHODS

Between 1998 and 2010 the parents of 259 index patients with grade III-V vesicoureteral reflux were asked permission to screen siblings younger than age 6 years for vesicoureteral reflux. Parents of index patients with affected siblings were contacted to obtain detailed information regarding vesicoureteral reflux, recurrent urinary tract infections, end stage renal disease, hypertension and nephrectomy among first, second and third-degree relatives.

RESULTS

A total of 300 siblings of the 259 index patients were found to have vesicoureteral reflux on voiding cystourethrography. In terms of the other relatives of the 259 index patients 127 also had radiologically proven vesicoureteral reflux. Reflux related morbidity among the first, second and third-degree relatives included end stage renal disease in 21, nephrectomy in 12 and hypertension in 4. Of the 212 siblings who had dimercapto-succinic acid scans 49 (23.1%) showed evidence of renal scarring. In 73% of the relatives vesicoureteral reflux was seen on the mother's side.

CONCLUSIONS

This study, the first to our knowledge, provides important information regarding reflux related morbidity in a large cohort of familial vesicoureteral reflux in first, second and third-degree relatives of index patients. Our data clearly show that there is an increased risk of reflux related morbidity among the relatives of index patients with vesicoureteral reflux and this finding has implications for counseling.

Incidence of febrile urinary tract infections in children after successful endoscopic treatment of vesicoureteral reflux: a long-term follow-up

OBJECTIVE

To evaluate the incidence of febrile urinary tract infection (UTI) after successful endoscopic correction of intermediate and high-grade vesicoureteral reflux (VUR).

STUDY DESIGN

Medical records of 1271 consecutive children (male, 411; female, 903) who underwent successful endoscopic correction of VUR were reviewed. Factors potentially influencing postoperative UTIs, such as history of presentation, age, sex, grade of VUR, renal scarring, and agent used for the endoscopic injection, were analyzed.

RESULTS

Febrile UTI developed in 73 children (5.7%) after successful endoscopic correction of VUR. Thirty-nine children had a single episode of UTI, and 34 children had two or more episodes at 1 month to 5.9 years (median, 1 year) after correction of VUR. With multivariate analysis, female sex (P < .001), history of preoperative bladder/bowel dysfunction (BBD; P = .005), and BBD after endoscopic correction (P = .001) were revealed to be the most important independent risk factors for a febrile UTI after successful correction of VUR.

CONCLUSIONS

The incidence of febrile UTIs after successful correction of intermediate and high grade VUR is low. Female sex and BBD were the most important risk factors in the development of febrile UTI. Our data supports the importance of assessing bladder and bowel habits in older children with febrile UTIs after endoscopic correction of VUR.

Adult care of children from pediatric urology

PURPOSE

In this article we highlight the difference, from established adult urology, in required approach to the care of adolescents and young adults presenting with the long-term consequences of the major congenital anomalies of the genitourinary tract. We review some abnormalities of the kidneys, progressive renal failure and disorders of bladder function from which general conclusions can be drawn.

MATERIALS AND METHODS

The published literature was reviewed and augmented with material from our institutional databases. For renal function the CAKUT (congenital abnormalities of the kidney and urinary tract) database at University College London Hospitals was used, which includes 101 young adult patients with CAKUT in whom the urinary tract has not been diverted or augmented. For bladder function some data are from patient records at Boston Children's Hospital.

RESULTS

Adolescents who grow up with the burden of a major congenital anomaly have an overwhelming desire to be normal. Many achieve high levels of education and occupy a wide range of employment scenarios. Babies born with damaged kidneys will usually experience improvement in renal function in the first 3 years of life. Approximately 50% of these cases will remain stable until puberty, after which half of them will experience deterioration. Any urologist who treats such patients needs to test for proteinuria as this is a significant indicator of such deterioration. In its absence, the urologist must have a reasonable strategy for seeking a urological cause. The most effective management for nephrological renal deterioration is with angiotensin converting enzyme inhibitors, which slow but do not prevent end stage renal failure. Renal deterioration is generally slower in these patients than in those with other forms of progressive renal disease. The bladder is damaged by obstruction or by functional abnormalities such as myelomeningocele. Every effort should be made to stabilize or reconstruct the bladder in childhood. A dysfunctional bladder is associated with or causes renal damage in utero, but continued dysfunction will cause further renal damage. Bladder function often changes in puberty, especially in boys with posterior urethral valves who may experience high pressure chronic retention. Dysfunction is managed with antimuscarinic drugs, clean intermittent self-catheterization and intestinal augmentation. Adult urologists must be able to manage the long-term problems associated with these treatments.

CONCLUSIONS

Pediatric conditions requiring management in adolescence are rare but have major, lifelong implications. Their management requires a broad knowledge of pediatric and adult urology, and could well be a specialty in its own right. Therefore, adult urologists must remain aware of the conditions, the problems that they may encounter and the special management required for these patients to live normal lives.

Urinary tract anomalies associated with high grade primary vesicoureteral reflux

BACKGROUND

Few studies have evaluated the significance of associated urological anomalies in vesicoureteral reflux (VUR). The aim of our study was to determine the incidence of associated urological anomalies in patients with high grade VUR and to assess their impact on renal parenchymal scarring.

METHODS

We retrospectively reviewed the hospital records of 1,765 consecutive cases diagnosed with high grade VUR (Grade III-V) at our hospital between 1998 and 2010. The diagnosis of VUR was made by a voiding cystourethrogram (VCUG). Renal scarring was evaluated by dimercapto-succinic acid (DMSA) scintigraphy and classified into three groups: mild (focal defects in uptake between 40 and 45%), moderate (uptake of renal radionuclide between 20 and 40%), and severe (shrunken kidney with relative uptake <20%). All associated urological anomalies were diagnosed by ultrasound or VCUG or DMSA scan.

RESULTS

Associated urological anomalies were present in 229 (13%) children. There were 87 boys and 142 girls. Duplex kidney was the main associated anomaly occurring in 148 (64.6%) of the 229 patients. Other anomalies were: bladder diverticulum in 29, solitary kidney in 12, ureterocele in 13, hypospadiasis in 11, pelviureteric junction obstruction in 9, malrotated kidney in 3, horseshoe kidney in 2, crossed fused ectopia in 1 and renal cyst in 1. DMSA scan revealed renal scarring in 105 (47.7%) of the 220 children who had a DMSA scan. 75 (50.7%) children with duplex kidneys showed renal scarring.

CONCLUSION

Associated urological anomalies occur commonly in patients with high grade VUR. Our data shows that nearly half of the patients with VUR and associated urological anomalies have renal scarring. Early recognition and treatment of VUR patients with associated urological anomalies may decrease the risk of renal parenchymal damage.

Prediction of high-grade vesicoureteral reflux after pediatric urinary tract infection: external validation study of procalcitonin-based decision rule

BACKGROUND

Predicting vesico-ureteral reflux (VUR) ≥3 at the time of the first urinary tract infection (UTI) would make it possible to restrict cystography to high-risk children. We previously derived the following clinical decision rule for that purpose: cystography should be performed in cases with ureteral dilation and a serum procalcitonin level ≥0.17 ng/mL, or without ureteral dilatation when the serum procalcitonin level ≥0.63 ng/mL. The rule yielded a 86% sensitivity with a 46% specificity. We aimed to test its reproducibility.

STUDY DESIGN

A secondary analysis of prospective series of children with a first UTI. The rule was applied, and predictive ability was calculated.

RESULTS

The study included 413 patients (157 boys, VUR ≥3 in 11%) from eight centers in five countries. The rule offered a 46% specificity (95% CI, 41-52), not different from the one in the derivation study. However, the sensitivity significantly decreased to 64% (95%CI, 50-76), leading to a difference of 20% (95%CI, 17-36). In all, 16 (34%) patients among the 47 with VUR ≥3 were misdiagnosed by the rule. This lack of reproducibility might result primarily from a difference between derivation and validation populations regarding inflammatory parameters (CRP, PCT); the validation set samples may have been collected earlier than for the derivation one.

CONCLUSIONS

The rule built to predict VUR ≥3 had a stable specificity (ie. 46%), but a decreased sensitivity (ie. 64%) because of the time variability of PCT measurement. Some refinement may be warranted.

Persistent renin-angiotensin system activation after anti-reflux surgery and its management

PURPOSE

To study renin-angiotensin system activation and the role of angiotensin-converting enzyme inhibition (ACE-I) after anti-reflux surgery.

MATERIAL AND METHODS

Thirty nine children underwent anti-reflux surgery for high grades of primary VUR. Plasma renin activity (PRA), urinary microalbumin, renal scars, split renal function (SRF), glomerular filtration rate (GFR), serum creatinine, blood pressure and episodes of breakthrough urinary tract infection were monitored in the early (5.9 ± 3.9; range 3-9 months) and late (27.1 ± 6.5; range 15-36 months) postoperative phase, before and after therapy with ACE-I (mean period 13.6 ± 2.5; range 10-24 months).

RESULTS

The early postoperative improvement in renal parameters (rise in SRF and GFR by 11.2% and 7.3%, respectively, and fall in PRA by 68.8%), was not sustained subsequently (minimal improvement in SRF, 7.4%, and GFR, 0.14%, was accompanied by a rise in PRA by 92.3%). After ACE-I therapy, improvement was noted in SRF and GFR by 0.5% and 7.5%, respectively, and there was a fall in urinary microalbumin by 52.3%.

CONCLUSIONS

Significant down regulation of rennin-angiotensin system activation and the accompanying improvement in renal function seen early after surgery is not sustained during follow up. ACE-I aids renal recovery.

Pediatric febrile urinary tract infections: the current state of play

Studies undertaken in recent years have improved our understanding regarding the consequences and management of febrile urinary tract infections (UTIs), which are amongst the most common serious bacterial infections in childhood, with renal scarring a frequent outcome.

In the past pyelonephritic scarring of the kidney, often associated with vesico-ureteral reflux (reflux nephropathy) was considered a frequent cause of chronic renal insufficiency in children. Increasing recognition as a consequence of improved antenatal ultrasound, that the majority of these children had congenital renal hypo-dysplasia, has resulted in a number of studies examining treatment strategies and outcomes following UTI.

In recent years there is a developing consensus regarding the need for a less aggressive therapeutic approach with oral as opposed to intravenous antibiotics, and less invasive investigations, cystourethrography in particular, following an uncomplicated first febrile UTI. There does remain a concern that with this newer approach we may be missing a small subgroup of children more prone to develop severe kidney damage as a consequence of pyelonephritis, and in whom some form of intervention may prove beneficial. These concerns have meant that development of a universally accepted diagnostic protocol remains elusive.

Vesicoureteral Reflux, a Scarred kidney, and Minimal Proteinuria: An Unusual Cause of Adult Secondary Hypertension

Hypertension affects about 65 million individuals in the United States. In adult patients, primary aldosteronism and renovascular causes are described as most prevalent. Vesicoureteral reflux as a cause of hypertension, while commonly described in pediatric populations, is less prevalent in the adult population especially in the absence of proteinuria. We present the case of a 31-year-old female presenting with early onset hypertension. Workup for renovascular hypertension was unrevealing. She was found to have right-sided vesicoureteral reflux with a unilateral scarred kidney. Patient underwent a nephrectomy with marked improvement in blood pressure control.