Antibiotics and surgery for vesicoureteric reflux: a meta-analysis of randomised controlled trials

Vesicoureteral Reflux in Transplanted Kidney Among Children With Congenital Anomalies of Kidney and Urinary Tract: Case-Control Study Assessing Impact on Renal Function and Graft Survival

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) are a common cause of kidney failure in childhood. Renal transplantation is the modality of treatment used for kidney failure that promotes improved quality of life for pediatric patients. It is believed that patients with CAKUT are more predisposed to developing graft reflux in the post-transplant period, but its influence on graft survival is poorly understood. A comparative analysis between patients with and without VUR in the graft was made to determine the impact of reflux on graft function and survival in pediatric CAKUT patients.

METHODS

A retrospective case-control study of patients undergoing first renal transplantation between April 2008 and October 2021 was done. The study included CAKUT individuals who underwent voiding cystourethrogram after transplantation. Patients were stratified into a group without reflux in the transplanted kidney (controls) and a group with reflux (cases). Six-year graft and patient survivals were calculated and compared using Kaplan-Meier curves and the log-rank test.

RESULTS

A total of 257 CAKUT patients were studied. Of this group, 63 (24%) underwent voiding cystourethrogram after transplantation, and 48 (76%) had reflux in the transplanted kidney. Estimated six-year survival of the graft was 72% in the control group versus 96% in the case group (log-rank 0.889). The median follow-up time after transplantation in years was 7.6 in controls and 6.6 in cases (p = 0.383).

CONCLUSIONS

Pediatric patients with CAKUT who presented reflux in transplanted kidneys had similar graft and patient survivals compared to patients without reflux.

Pyeloplasty for the treatment of ectopic renal hydronephrosis in adults: a case series of six patients

Background

Ectopic renal hydronephrosis is a relatively rare condition, with literature primarily consisting of scattered case studies. The ectopic kidney poses technical challenges to surgeons due to its structural and anatomical abnormalities. This study aims to share our initial experiences with minimally invasive pyeloplasty as a management approach for ectopic renal hydronephrosis in adult patients.

Case Description

Between August 2018 and January 2023, six patients underwent minimally invasive pyeloplasty for ectopic kidneys. The patient cohort consisted of four individuals with pelvic kidneys, one with an iliac kidney, and one with an abdominal kidney. Among these, three cases were left-sided, two were right-sided, and one was isolated. The median patient age was 27 (range, 18-45) years. Four patients underwent robot-assisted laparoscopic pyeloplasty, while two underwent laparoscopic pyeloplasty. The median operative time was 134 (range, 63-240) minutes. After a median follow-up duration of 28.5 (range, 6-59) months, two patients required nephrectomy, with vesicoureteral reflux (VUR) and malrotation potentially contributing to surgical failure in these cases. The remaining four patients showed either stable or improved hydronephrosis and renal function. The overall operative success rate was 66.7%.

Conclusions

The rarity and anatomical variations of ectopic kidneys hinder the standardization of surgical approaches. The integration of three-dimensional (3D) virtual reconstruction and tailored surgical techniques contributes to enhanced outcomes in ectopic renal hydronephrosis cases. Furthermore, continued research and refinement of surgical approaches are needed.

Recurrence of vesico-ureteral reflux in children: is still the endoscopic injection the best option?

Background

Endoscopic injection (EI) is a safe treatment for vesico-ureteral reflux (VUR) in children, but recurrences are not insignificant. This study aims to show if multiple EI is still the best first line management even if in case of recurrences.

Methods

All patients affected by primary VUR, treated with at least one EI and with at least 5 years follow up were included. All general data were analyzed. Recurrence rate after one, two and three EIs were calculated.

Results

One hundred and sixty-one patients (total number =210) were healed after 1 injection, 28 after 2 and 4 after 3 with a global success rate of 91.90%. Recurrence rate is higher in patients older than 3 years old and with IV and V reflux grade. Even if 67.7% of recurrent VUR after one injection was symptomatic, diagnosis of recurrences after multiple EI was mainly radiological. Only 8% of the patients underwent EI need an anti-reflux surgery.

Conclusions

Thanks to its low costs and the acceptable recurrence rate, Deflux EI should be proposed as the first therapeutic approach for children affected by VUR, especially in those with low and moderate grades of VUR. Multiple injections could be contraindicated only in older children thank 1 year with high-grade VUR (IV symptomatic and V grade).

Effectiveness of various treatment modalities in children with vesicoureteral reflux grades II-IV: a systematic review and network meta-analysis

BACKGROUND

Vesicoureteral reflux (VUR) is one of the most common risk factors of urinary tract infection (UTI) among children. Various treatment modalities including antibiotic prophylaxis, surgical or endoscopic corrections and conservative treatment were used depending on the severity of VUR. The aim of this study is to compare the effectiveness of these treatment modalities in children with VUR grades II-IV by conducting a systematic review and network meta-analysis.

METHODS

A systematic search from different databases was performed from their earliest records to December 2022 without any language restriction. Only randomised controlled trials were included in this study. Effectiveness of treatment modalities was mainly compared by UTI. Other outcomes for renal scarring and resolution by renal units were also measured between treatments.

RESULTS

A total of 11 studies with 1447 children were included in this study. While comparing with antibiotic prophylaxis in network meta-analysis for UTI recurrence, surgical treatment probably lowers the rate of UTI recurrence (Log OR -0.26, 95% CI -0.54 to 0.02, high quality). However, endoscopic treatment (Log OR 0.2, 95% CI -1.41 to 1.81, high quality) and conservative treatment (Log OR 0.15, 95% CI -0.45 to 0.75, high quality) revealed probably inferior to antibiotic treatment.

CONCLUSION

Both pairwise and network meta-analytic results probably showed no difference between the treatments in terms of their impact on UTI recurrence, progression of previous renal scars, or formation of new renal scars in children with VUR grades II-IV. These findings may offer a better understanding of each treatment and evidence-based suggestions for the choice of treatment, which should be individualised and based on the patient's risk factors.

Contemporary Management of Urinary Tract Infections in Children

Purpose of Review

Urinary tract infection (UTI) in children is a major source of office visits and healthcare expenditure. Research into the diagnosis, treatment, and prophylaxis of UTI has evolved over the past 10 years. The development of new imaging techniques and UTI screening tools has improved our diagnostic accuracy tremendously. Identifying who to treat is imperative as the increase in multi-drug-resistant organisms has emphasized the need for antibiotic stewardship. This review covers the contemporary management of children with UTI and the data-driven paradigm shifts that have been implemented into clinical practice.

Recent Findings

With recent data illustrating the self-limiting nature and low prevalence of clinically significant vesicoureteral reflux (VUR), investigational imaging in children has become increasingly less frequent. Contrast-enhanced voiding urosonogram (CEVUS) has emerged as a useful diagnostic tool, as it can provide accurate detection of VUR without the need of radiation. The urinary and intestinal microbiomes are being investigated as potential therapeutic drug targets, as children with recurrent UTIs have significant alterations in bacterial proliferation. Use of adjunctive corticosteroids in children with pyelonephritis may decrease the risk of renal scarring and progressive renal insufficiency. The development of a vaccine against an antigen present on Escherichia coli may change the way we treat children with recurrent UTIs.

Summary

The American Academy of Pediatrics defines a UTI as the presence of at least 50,000 CFU/mL of a single uropathogen obtained by bladder catheterization with a dipstick urinalysis positive for leukocyte esterase (LE) or WBC present on urine microscopy. UTIs are more common in females, with uncircumcised males having the highest risk in the first year of life. E. coli is the most frequently cultured organism in UTI diagnoses and multi-drug-resistant strains are becoming more common. Diagnosis should be confirmed with an uncontaminated urine specimen, obtained from mid-stream collection, bladder catheterization, or suprapubic aspiration. Patients meeting criteria for imaging should undergo a renal and bladder ultrasound, with further investigational imaging based on results of ultrasound or clinical history. Continuous antibiotic prophylaxis is controversial; however, evidence shows patients with high-grade VUR and bladder and bowel dysfunction retain the most benefit. Open surgical repair of reflux is the gold standard for patients who fail medical management with endoscopic approaches available for select populations.

Routine evaluation of vesico-ureteric reflux in children with anorectal malformation does not reduce the rate of urinary tract infection

OBJECTIVE

Children with anorectal malformations (ARM) have a high rate of renal anomalies and increased risk of urinary tract infection (UTI). We aimed to determine whether using routine Micturating Cystourethrogram (MCUG) to detect VUR is effective in reducing the incidence of UTI or renal scarring in children with ARM.

METHODS

A retrospective study of consecutive children diagnosed with ARM in two centres with a minimum of 3 years follow-up was performed, excluding those with cloaca or an MCUG prior to ARM repair. Univariate and multivariate logistic regression analysis was used to determine variables which were associated with VUR, UTI and renal scarring. Associations are described as Odd's Ratio (OR), 95% Confidence Interval. Significance was taken as p<0.05.

RESULTS

344 children were included with a median age of 8 years (IQR 5-11 years). 150 (44%) were female. 89 (26%) had renal anomalies and 101 (29%) had spine anomalies. 148 patients had routine MCUG and VUR was found in 62 (42%) of these children. Univariate analysis did not correlate any of the assessed variables with VUR or renal scarring. However, abnormal renal ultrasound - OR 6.18 (95% CI 2.99-13.07, p 0.0001) was associated with UTI whilst abnormal spine - OR 0.27 (95% CI 0.10-0.62, p 0.009), low ARM - OR 0.30 (CI 0.14-0.63, p 0.006) and intermediate ARM - OR 0.35 (CI 0.17-0.70, p 0.01) were associated with a reduced risk of UTI. On multivariate analysis, only abnormal renal USS retained a significant association with UTI (p<0.0001).

CONCLUSIONS

VUR is common in patients with ARM. Children with an abnormal R-USS are at increased risk of UTI. Performing routine MCUG does not reduce the risk of UTI in children with ARM.

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.

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.

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.

Local Trends in the Evaluation and Treatment of Urinary Tract Infections and Vesicoureteral Reflux in Children

INTRODUCTION

The management of urinary tract infection in children has changed in the last decade due to worries about antibiotic overuse, and the trauma and radiation of voiding cystourethrograms. We examined whether there has been a change in the management of pediatric urinary tract infection in our practice.

METHODS

We reviewed billing records from 2005 to 2013 to determine the number of voiding cystourethrograms performed as well as the number of operations (open and endoscopic) for vesicoureteral reflux. We also determined the number of patients seen in the office for urinary tract infection or vesicoureteral reflux and hospital admissions for urinary tract infection or pyelonephritis.

RESULTS

There was a dramatic decrease in the number of voiding cystourethrograms performed from 907 in 2005 to 216 in 2013. The number of operations for vesicoureteral reflux increased to a peak of 73 in 2007 and decreased to 17 in 2013. Office visits for urinary tract infection or vesicoureteral reflux were unchanged from 2006 to 2013 (602 and 470, respectively). Pediatric hospitalizations for urinary tract infection trended only slightly upward from 2005 to 2013 (71 and 84, respectively).

CONCLUSION

Our results demonstrate a marked decrease in the diagnosis and treatment of vesicoureteral reflux in the last decade with no significant change in the number of patients seen for urinary tract infection. If confirmed nationally, this has major clinical, educational and health care quality improvement implications.

To screen or not to screen for vesicoureteral reflux in children with ureteropelvic junction obstruction: a systematic review

Ureteropelvic junction obstruction (UPJO) and vesicoureteral reflux (VUR) are the most common uropathies. The co-occurrence of both anomalies has led to the practice of screening for VUR in children with UPJO to prevent deterioration of kidney function due to renal scarring following urinary tract infections (UTIs). We determined the prevalence of VUR in children with UPJO for a critical assessment of VUR screening by voiding cystourethrography (VCUG). A systematic search strategy in MEDLINE, EMBASE, and CENTRAL was carried out for all articles that included VCUG, and renal scintigraphy or any other appropriate imaging technique for the diagnosis of UPJO. Twenty studies were eligible for inclusion. We found a pooled prevalence for VUR of 8.2 % (95 % CI = 3.6-12.7), about a threefold increase compared to the general pediatric population. VUR occurred bilateral or contralateral to the kidney with UPJO in 5.7 % (95 % CI = 3.0-8.5), equivalent to 75 % of all children with VUR. Considering the effect size of VUR treatment with antibiotics, about 207 and 278 children would need to undergo VCUG to prevent one febrile UTI and one case of renal scarring by 1-2 years, respectively.

CONCLUSION

Against this background, screening for VUR needs to be scrutinized and restricted to selected risk groups. What is known: • Screening of patients with ureteropelvic junction obstruction (UPJO) for vesicoureteral reflux (VUR) is recommended based on a small number of repeatedly cited studies. • The lack of conclusive evidence results in different treatment strategies and leads to difficulties when communicating diagnoses and treatment options to parents. What is new: • A robust prevalence for VUR in children with UPJO based on all published evidence and the resulting number needed to screen are given for decision-making in daily clinical practice. • The results may be a precursor for implementation into guidelines.

Parental Preference Assessment for Vesicoureteral Reflux Management in Children

PURPOSE

Parents of children with vesicoureteral reflux are presented with a variety of management options, which in many cases offer a similar risk-benefit ratio. To facilitate shared decision making, parental preferences regarding vesicoureteral reflux treatment options need to be acknowledged. We aimed to characterize the clinical experience of parents and elicit core themes affecting decision making in regard to managing vesicoureteral reflux in their child.

MATERIALS AND METHODS

A semistructured, qualitative interview script was developed and vetted by 25 pediatric urologists to discuss treatment options for vesicoureteral reflux. Additional patient interviews were conducted until new themes failed to arise. Content analysis was performed to extract all statements that described treatment options. Similar statements were combined until a final list of unique themes emerged.

RESULTS

A total of 26 interviews were performed, yielding 689 statements about overall parent experiences with managing vesicoureteral reflux in the child and 450 statements (65%) pertaining to treatment options. Of the 13 themes that emerged, those most commonly considered were the prevention of future urinary tract infections by 85% of parents, the efficacy rate of treatment options by 85%, the burden of daily maintenance or compliance by 77%, antibiotic resistance by 69%, chronic kidney damage by 62% and invasiveness by 58%.

CONCLUSIONS

Our study emphasizes that when choosing a treatment option for vesicoureteral reflux in their child, parent preferences regarding risks and benefits are variable. However, their chief concerns include whether a method decreases the risk of urinary tract infections, has an acceptable efficacy rate and aligns itself with the capabilities of the family. These themes help frame discussions between families and clinicians regarding vesicoureteral reflux management, and they can facilitate shared decision making.

Antireflux surgery does not change ongoing renal functional deterioration

AIM

Treatment modalities of vesicoureteral reflux (VUR) consist of antimicrobial prophylaxis and antireflux surgery. In this study, we aimed to determine if antireflux surgery changes the course of renal functional deterioration in children with VUR and urinary tract infections (UTI).

METHODS

Medical files of patients with VUR diagnosed during evaluation for UTI were evaluated retrospectively for gender, age, follow-up period, and renal ultrasonography (US) and serial 99mTc-dimercaptosuccinic acid (99mTc-DMSA) scintigraphy findings. Estimated glomerular filtration rate and urinary protein levels were determined at the initial and last visits, and before the operation in children who had antireflux surgery. The patients were divided into two groups as solely medically treated (Group 1) and both medically and surgically treated (Group 2). Group 2 was further divided as those with stable renal function (Group 2a) and with progressive renal injury (Group 2b).

RESULTS

There were 140 patients (77 female; mean age 51.6 ± 51.9 months). Group 1 and Group 2 included 82 and 58 patients, respectively. In Group 2, the number of patients with the abnormal US, DMSA scintigraphy, and renal function was higher than in Group 1. Recurrent UTI rate was similar, but progressive scarring was more prominent in the antireflux surgery group. In Group 2, 31 patients had a stable renal function (Group 2a) while 27 had progressive deterioration of renal functions (Group 2b). These subgroups were not different with respect to the rate of high-grade VUR, the presence of a renal scar in DMSA, and UTI recurrence. However, the bilateral renal scar was more common in Group 2b.

CONCLUSION

Antireflux surgery does not change the course of ongoing renal injury and renal functional deterioration.

Renal Ultrasound for Infants Younger Than 2 Months With a Febrile Urinary Tract Infection

OBJECTIVE

The purpose of this study is to determine the performance of renal ultrasound for detecting vesicoureteral reflux (VUR) and obstructive uropathies in infants younger than 2 months with a febrile urinary tract infection (UTI).

MATERIALS AND METHODS

We performed a retrospective cohort study of infants younger than 2 months with fever and culture-proven UTI presenting from July 1, 2008, through December 31, 2011, with renal ultrasound and voiding cystourethrogram (VCUG) performed within 30 days of UTI diagnosis. Two pediatric radiologists independently reviewed the renal ultrasound and VCUG findings. Results of the renal ultrasound were deemed abnormal if collecting system dilation, renal size asymmetry, collecting system duplication, urothelial thickening, ureteral dilation, or bladder anomalies were present. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of renal ultrasound were calculated using VCUG as reference standard.

RESULTS

Of the 197 patients included (mean [SD] age, 33 [ 15 ] days; male-to-female ratio, 2:1), 25% (n = 49) had VUR grades I-V, with 16% (n = 31) having VUR grades III-V and 8% (n = 15) having VUR grades IV-V. For grades I-V VUR, sensitivity was 32.7% (95% CI, 20.0-47.5%), specificity was 69.6% (95% CI, 61.5-76.9%), PPV was 26.2% (95% CI, 15.8-39.1%), and NPV was 75.7% (95% CI, 67.6-82.7%). For grades III-V VUR, sensitivity was 51.6% (95% CI, 33.1-69.9%), specificity was 72.9% (95% CI, 65.5-79.5%), PPV was 26.2% (95% CI, 15.8-39.1%), and NPV was 89.0% (95% CI, 82.5-93.7%). For grades IV-V VUR, sensitivity was 86.7% (95% CI, 59.5-98.3%), specificity was 73.6% (95% CI, 66.6-79.9%), PPV was 21.3% (95% CI, 11.9-33.7%), and NPV was 98.5% (95% CI, 94.8-99.8%). No obstructive uropathies were diagnosed by VCUG in patients with normal renal ultrasound findings.

CONCLUSION

In infants younger than 2 months, a normal renal ultrasound makes the presence of grades IV and V VUR highly unlikely but does not rule out lower grades of VUR.

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.

Persistence and recurrence of vesicoureteric reflux in children after endoscopic therapy - implications of a risk-adapted follow-up

Introduction

There is no well-defined follow-up scheme available to reliably detect persistent or recurrent vesicoureteric reflux (VUR) after endoscopic therapy (ET), but also to reduce postoperative invasive diagnostics in these children.

Our aim was the evaluation of possible predictors of persistence and recurrence of VUR, in order to elaborate and test a risk-adapted follow-up regimen.

Material and methods

92 patients (85/92%f, 7/8%m, age 2.99y) underwent direct isotope cystography (DIC) three months after ET. Persistent or recurrent VUR, scarring on dimercaptosuccinic acid (DMSA) scans and further fUTIs after therapy (follow-up 24.6 m) were documented and analysed.

Results

VUR persistence 3 months after ET was found in 11 (11.9%) patients; recurrent VUR in 4 (4.3%) patients. Scarring on preoperative DMSA and dilating VUR (°III and °IV) were significantly associated with recurrent VUR. If only children with preoperative positive DMSA scan or dilating VUR would have undergone DIC, only 58/92 DICs (64%) would have been necessary. Only 45.5% of otherwise detected VURs would have been identified using this risk-adapted strategy.

Conclusions

Limiting invasive follow-up diagnostics (VCUG) and, therewith, the radiation burden in a predefined group of patients at risk for persistence or recurrence of VUR is not recommended, due to the significant chance of missing persistent or new onset contralateral VUR. Therefore, we recommend a routine follow-up VCUG after ET. Further prospective scientific efforts to evaluate new, alternative factors influencing persistence and recurrence of VUR, in order to establish an effective follow-up strategy, are warranted.

Antibiotic prophylaxis in the management of vesicoureteric reflux: a randomized double-blind placebo-controlled trial

BACKGROUND

The benefits of long-term low-dose antibiotics in preventing urinary tract infection (UTI) and renal damage in children with primary vesicoureteric reflux (VUR) are unclear.

METHODS

Children aged between 1 and 12 years with VUR grade I-IV and a microbiologically proven UTI were randomized into two groups to receive either antibiotic prophylaxis [2 mg/kg trimethoprim + sulfamethoxazole (TMP-SMX)] daily or placebo, respectively, for 12 months. Primary outcome was microbiologically confirmed symptomatic UTI. Intention-to-treat analysis using time-to-event data was performed.

RESULTS

A total of 93 children (66.7 % boys) with a median age of 4.6 years were enrolled in this study; VUR grade III-IV was present in 73.1 % of these children. At least one symptomatic UTI occurred in ten (21.3 %) patients receiving antibiotic prophylaxis and in three (6.5 %) patients receiving placebo [hazard ratio in antibiotic group 3.9; 95 % confidence interval (CI) 1- 14; log rank test P = 0.02). Compared to the group receiving placebo, the antibiotic group had a 14.8 % increased risk for developing UTI (95 % CI 1-28; P = 0.03). Of the total number of episodes of UTI, 58.3 % of those in the antibiotic group were caused by TMP-SMX-resistant bacteria compared to 20 % in the placebo group (P = 0.15). A renal scan at 12 months revealed that six of 37 (16.2 %) patients in the antibiotic group and seven of 43 (16.3 %) patients in the placebo group had new or worsening of pre-existing scar.

CONCLUSIONS

Long-term antibiotic prophylaxis with TMP-SMX is associated with increased risk of symptomatic UTI compared to placebo in children with grade I-IV VUR.

Lower radiation burden in state of the art fluoroscopic cystography compared to direct isotope cystography in children

INTRODUCTION

Both, fluoroscopic voiding cystourethrography (fVCUG) and direct isotope cystography (DIC) are diagnostic tools commonly used in pediatric urology. Both methods can detect vesicoureteral reflux (VUR) with a high sensitivity. Whilst the possibility to depict anatomical details and important structures as for instance the urethra in boys or the detailed calyceal anatomy are advantages of fVCUG, a lower radiation burden is thought to be the main advantage of DIC. In the last decade, however, a rapid technical evolution has occurred in fluoroscopy by implementing digital grid-controlled, variable rate, pulsed acquisition technique. As documented in literature this led to a substantial decrease in radiation burden conferred during fVCUGs.

OBJECTIVE

To question the common belief that direct isotope cystography confers less radiation burden compared to state of the art fluoroscopic voiding cystography.

STUDY DESIGN

Radiation burden of direct isotope cystography in 92 children and in additional 7 children after an adaption of protocol was compared to radiation burden of fluoroscopic voiding cystourethrography in 51. The examinations were performed according to institutional protocols. For calculation of mean effective radiation dose [mSv] for either method published physical models correcting for age and sex were used. For DIC the model published by Stabin et al., 1998 was applied, for fVCUG two different physical models were used (Schultz et al., 1999, Lee et al., 2009).

RESULTS

The radiation burden conferred by direct isotope cystography was significantly higher as for fluoroscopic voiding cystourethrography. The mean effective radiation dose for direct isotope cystography accounted to 0.23 mSv (± 0.34 m, median 0.085 mSv) compared to 0.015 mSv (± 0.013, median 0.008 mSv, model by Schultz et al.) - 0.024 mSv (± 0.018, median 0.018 mSv, model by Lee et al.) for fluoroscopic voiding cystourethrography. After a protocol adaption to correct for a longer examination time in DIC that was caused by filling until calculated bladder capacity, mean radiation burden accounted to .07 mSv (median 0.07 mSv) and the values were less scattered.

DISCUSSION

As it had to be expected from literature, radiation dose from fVCUG, if modern image acquisition techniques are used, is even less than from DIC. In our protocol, according to nuclear medicine standards, bladders were filled until calculated capacity. This resulted in a longer examination time for the patients with a higher functional capacity, resulting in relatively higher radiation burden. However, also if the protocol is changed or only the patients with relatively fast bladder emptying are considered, radiation burden conferred by DIC is higher (at least × 2.9, comparing the "worst" case for fVCUG with the "best" case for DIC). Absolute radiation burden conferred by either exam is extremely low compared to other medical radiation exposures as well as to environmental radiation. Consequently it is most probably not relevant for the individual childs future risk for cancer or other radiation damage. However, because of repeated investigations with correspondingly higher radiation burden in this patient group the ALARA (as low as reasonably achievable) principle should lead to a optimized use of fVCUG rather than an uncritical use of DIC, given that modern acquisition standards are available and radiation measurement is performed. Also, fVCUG provides more information concerning anatomical details compared to DIC.

CONCLUSION

Contrary to common beliefs, effective radiation dose conferred during fluoroscopic voiding cystourethrography is significantly lower than during direct isotope cystography. The prerequisite for our findings, however, is the use of modern image acquisition tools and an optimized protocol. Both exams confer low radiation doses probably only relevant to children undergoing repeated radiation exposure. Nevertheless, this findings should be considered in indication for either exam in order to reduce the radiation burden to a minimum whilst optimizing the information yield.

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.

Evaluation and management of recurrent urinary tract infections in children: state of the art

Urinary tract infections (UTIs) represent an important cause of febrile illness in young children and can lead to renal scarring and kidney failure. However, diagnosis and treatment of recurrent UTI in children is an area of some controversy. Guidelines from the American Academy of Pediatrics, National Institute for Health and Clinical Excellence and European Society of Paediatric Radiology differ from each other in terms of the diagnostic algorithm to be followed. Treatment of vesicoureteral reflux and antibiotic prophylaxis for prevention of recurrent UTI are also areas of considerable debate. In this review, we collate and appraise recently published literature in order to formulate evidence-based guidance for the diagnosis and treatment of recurrent UTI in children.

Gender-based differences in pediatric nuclear medicine

Gender-based differences commonly encountered in pediatric nuclear medicine reflect both basic embryologic differences of the sexes, which are evident from infancy, and evolving physiological changes due to gender, which occur as the pediatric patient grows, undergoes puberty, and matures to adulthood. It is important for a nuclear medicine physician or radiologist to know both the gender and the age of a patient when interpreting her or his studies. It is also important that the reading physician be familiar with the normally evolving physiological changes that are specific for that patient's stage of development. It is particularly important that the reading physician consider such changes when comparing serial studies of the patient that are acquired during the patient's transitions through her or his different significant stages of development. Many pediatric nuclear medicine imaging protocols are modifications or adaptations of the protocols for adult imaging. Physicians reading pediatric studies must routinely incorporate knowledge on age and gender that is relevant to the patient for any given study. The age-defined gender-based subtleties of potential findings in pediatric nuclear medicine studies are often underrecognized. However, they are often of interest and at times important in the workup of both benign entities and pathologic processes of the pediatric patient.

Paediatric urinary tract infections: a retrospective application of the National Institute of Clinical Excellence guidelines to a large general practitioner referred historical cohort

BACKGROUND

The National Institute for Clinical Excellence (NICE) is a United Kingdom nondepartmental public body accountable to the Department of Health. Before the introduction of the NICE guidelines in the United Kingdom most children younger than 1 year of age had a urinary tract ultrasound, cyclic micturating cystourethrogram and dimercaptosuccinic acid scintigraphy, the latter delayed 6 months post infection. Children older than 1 year had a urinary tract ultrasound only, and further imaging if necessary.

OBJECTIVE

Identify who would have been investigated had the NICE imaging strategy been used and who would not. Compare the diagnostic yield and patient outcome with the previous imaging protocol using our prospectively collected historical data.

MATERIALS AND METHODS

We applied the new imaging strategy to a historic cohort of 934 patients with a urinary tract infection (UTI) referred by general practitioners to a specialist children's hospital between 1996 and 2002.

RESULTS

Of the 934 patients referred, 218 would have been investigated according to the NICE guidelines. In total, there were 105 patients with abnormal imaging findings, and 44 of these (42%) would have been investigated under the NICE guidelines.

CONCLUSION

Applying the NICE guidelines to children presenting with UTI will reduce the number imaged by 77% and will lead to missed identification of 58% of imaging abnormalities in the group. The majority of these abnormalities may be important. While supporting conservative investigation protocols, we are concerned that many abnormalities might go undetected.

Relevance of current guidelines in the management of VUR

In recent years, there have been fundamental changes in the understanding of vesicoureteral reflux (VUR). This is reflected by current international guidelines that cover diagnosis, screening, and treatment of VUR. However, literature is still lacking and many questions are unsolved. In this article, we shortly review the important aspects of the current guidelines. Due to the lack of high-powered randomized controlled trials, guidelines often are based on an expert's opinion rather than evidence. In this review article, we address the controversies in the management of VUR; siblings and children with antenatally diagnosed hydronephrosis and the management of a patient with VUR.

CONCLUSION

With an individualized approach and patient risk stratification, the goal today must be to address the clinical problem, avoid unnecessary tests, and provide good quality of life for the patient and parents.

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.

Do antibiotic prophylaxis and/or circumcision change periurethral uropathogen colonization and urinary tract infection rates in boys with VUR?

BACKGROUND

To evaluate the effect of circumcision and/or antibiotic prophylaxis on periurethral flora and associated bacteriuria in male children with and without vesicoureteral reflux (VUR).

PATIENTS AND METHODS

The study included 91 boys with low-grade VUR and 106 healthy boys (control) without VUR. The boys with VUR were randomized as antibiotic prophylaxis only and antibiotic prophylaxis plus circumcision. The boys without VUR were randomized as circumcision group and followed-up group without circumcision. Periurethral swab and urine cultures were obtained from the participants at the beginning of the study, and at 1st, 3rd, 6th, 9th, and 12th month. The groups were compared in terms of positive periurethral and urine cultures.

RESULTS

The positive periurethral culture rate was significantly lower in the circumcised boys at all measurement times. The positive urine culture rate in the circumcised boys was lower than in the uncircumcised boys. Subgroup analysis based on age groups showed that age did not affect these statistical differences.

CONCLUSION

Circumcision decreases colonization of periurethral bacterial pathogenic flora. In boys with low-grade VUR, circumcision plus antibiotic prophylaxis prevented recurrent and febrile urinary tract infections.

Randomized clinical trial comparing endoscopic treatment with dextranomer hyaluronic acid copolymer and Cohen's ureteral reimplantation for vesicoureteral reflux: long-term results

PURPOSE

To compare efficacy of Cohen's ureteral reimplantation and endoscopic treatment with Dx/HA in patients with primary VUR grades II, III and IV.

METHODS

From April 2002 to June 2004, patients over 1 year old with VUR grade I, II, III or IV were included. Patients were randomized into two groups: endoscopic treatment (ET) or ureteral reimplantation (UR). In the ET group, an ultrasonography study was performed 24 h and 1 month after surgery, and two voiding cystourethrographies at 3 and 6 months post treatment. In the UR group, an ultrasonography study was done 7 days and 1 month after surgery and a micturial cystography 6 months post surgery. A postoperative nuclear direct cystogram was performed 5 years later in both groups.

RESULTS

A total of 41 patients were included in this study: in ET 22 patients with 35 refluxing ureters and in UR 19 patients with 32 refluxing ureters. The VUR grades in ET were: 16 grade II, 16 grade III and 3 grade IV; and in UR: 15 grade II, 12 grade III and 5 grade IV. VUR was resolved in 91% (32/35) of ET (28% of ureters needed a second injection), and in 100% of UR group. Five years after the procedure, VUR was still resolved in 30/32 of ET and 32/32 of UR.

CONCLUSION

Short- and long-term follow up shows that multiple endoscopic treatment of VUR grades II, III and IV with Dx/HA is as effective as ureteral reimplantation.

Clinical value of persistent but downgraded vesicoureteral reflux after dextranomer/hyaluronic acid injection in children

We aimed to investigate the clinical value of persistent but downgraded vesicoureteral reflux (VUR) after dextranomer/hyaluronic acid (Dx/HA) injection in children. The medical records of 128 children (195 ureters) who underwent Dx/HA injections for VUR were reviewed. The incidences of pre- and post-operative febrile urinary tract infections (UTIs) were analyzed in children with or without persistent VUR on voiding cystourethrography (VCUG) 3 months postoperatively. The surgical results of VUR persistent children who underwent a single additional injection were assessed. The VUR resolved completely in 100 ureters (51.3%), was persistent in 95 ureters, and newly developed in 2 ureters. The incidence of pre/post-operative febrile UTIs were 0.35 ± 0.39 per year and 0.07 ± 0.32 per year in VUR resolved children (P < 0.001), and 0.76 ± 1.18 per year and 0.20 ± 0.61 per year in VUR persistent children (P < 0.001). A single additional Dx/HA injection (44 ureters) resolved VUR in 29 ureters (65.9%), and also reduced the VUR to grade I in 7 ureters (15.9%), II in 4 (9.1%), and III in 4 (9.1%). Even in children with persistent VUR after Dx/HA injection, the incidence of febrile UTIs decreased markedly. The VUR grade significantly decreases after single additional Dx/HA injection.

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 impact of vesicoureteral reflux treatment on the incidence of urinary tract infection

Vesicoureteral reflux (VUR) is a heterogeneous disease and its management remains one of the most controversial topics in pediatrics. Management options include surveillance, antibiotics, and surgery. The approval of dextranomer/hyaluronic acid (DHA) as a bulking agent by the Food and Drug Administration was followed by wide acceptance of endoscopic techniques as a major tool in the management of reflux. Pyelonephritis rather than VUR is the most common cause of kidney damage in children. It should be emphasized that the primary goal of diagnosing and treating VUR should be preventing this complication. There are no sufficient data in the literature to address the impact of the different treatment modalities on the incidence of febrile urinary tract infections (feb-UTIs) denoting pyelonephritis, with very few studies evaluating endoscopic treatment in light of this clear and well-defined outcome. The fact that we can correct the anatomy at the vesicoureteral junction with a simple and relatively safe outpatient procedure does not justify offering it to all patients. In this review, we attempt to critically evaluate the available literature pertaining to the impact of different treatment modalities on reducing the incidence of febrile UTIs and kidney damage, with a special emphasis on endoscopic treatment.

The demographics and costs of inpatient vesicoureteral reflux management in the USA

This study evaluates the impact of vesicoureteral reflux (VUR) on the economy and inpatient healthcare utilization in the USA. A retrospective analysis was performed on children ≤ 18 years of age, hospitalized with the principal discharge diagnosis of VUR between 2000 and 2006, using the Healthcare Cost and Utilization Project Kids' Inpatient Database. The results are stratified as follows. First, by hospitalizations: between 2000 and 2006, 6,655  ±  720 (standard error) children/year were hospitalized with VUR. Since 2003, both the length of each hospitalization and the number of hospitalizations have decreased. Second, by related procedures/diagnoses: ureteral reimplantation was the most common procedure, accounting for 89% of hospitalizations. Congenital genitourinary anomalies, disorders of the kidney/ureter/bladder, and urinary tract infections (UTI) were the most common related diagnoses. Thirdly, by hospital economics: since 2000, hospital charges for VUR increased despite decreased lengths of hospitalization. By 2006, hospital charges rose to $18,798/hospitalization, and aggregate national charges exceeded $100 million. Our results indicate that fewer children with VUR are requiring inpatient management. Children with VUR are often hospitalized for ureteral reimplantation or the management of related diagnoses. Since 2000, hospital charges for inpatient VUR management have increased. More efforts are needed to evaluate cost-effective strategies for the evaluation and management of VUR.

Antimicrobial therapy of urinary tract infections in children

The main objectives in childhood urinary tract infections are rapid recovery from complaints, prevention of urosepsis and infection-related complications as well as the prevention of renal parenchymal damage. Calculated antibiotic therapy should take the local resistance rates of uropathogens into consideration. The current situation of bacterial resistances differs from region to region. In Escherichia coli, resistance rates against cephalosporins, aminoglycosides, nitrofurantoin und chinolones have been relatively low. In contrast, resistance rates against ampicillin have increased over the last 20 years. A similar trend has been observed for TMP/SMX. The choice of appropriate antibiotics, the duration of therapy and the form of application depend on age, severity of clinical symptoms and the presence of complicating factors. In early infancy, a combination of aminoglycoside/ampicillin or ceftazidime/ampicillin is commonly recommended as first-line treatment in pyelonephritis. Pyelonephritis in young infants should always be treated in a paediatric clinic. In later infancy and childhood, an oral third-generation cephalosporin can be used.

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 of these children has been directed at preventing UTI by antibiotic prophylaxis and/or surgical correction of VUR. The optimum strategy is not clear.

OBJECTIVES

To evaluate the benefits and harms of different treatment options for primary VUR.

SEARCH STRATEGY

In August 2010 we searched CENTRAL, MEDLINE and EMBASE and screened reference lists of papers and abstracts from conference proceedings.

SELECTION CRITERIA

RCTs in any language comparing any treatment of VUR including surgical or endoscopic correction, antibiotic prophylaxis, non-invasive non-pharmacological techniques and any combination of therapies.

DATA COLLECTION AND ANALYSIS

Two authors independently searched the literature, determined study eligibility, assessed quality, extracted and entered data. We expressed dichotomous outcomes as risk ratios (RR) and their 95% confidence intervals (CI) and continuous data as mean differences (MD) and their 95% CI's Data were pooled using the random effects model.

MAIN RESULTS

Twenty RCTs (2324 children) were included. Long-term low-dose antibiotic prophylaxis compared to no treatment/placebo did not significantly reduce repeat symptomatic UTI (846 children: RR 0.68, 95% CI 0.39 to 1.17) or febrile UTI (946 children: RR 0.77, 95% CI 0.47 to 1.24) at two years. There was considerable heterogeneity in the analyses and only one study was adequately blinded. At one to three years, antibiotic prophylaxis reduced the risk of new or progressive renal damage on DMSA scan (446 children: RR 0.35, 95% CI 0.15 to 0.80). Side effects were infrequent when reported, but antibiotics increased the likelihood of bacterial drug resistance threefold (132 UTIs: RR 2.94, 95% CI 1.39 to 6.25).When long-term antibiotic prophylaxis was compared with surgical or endoscopic correction of VUR plus antibiotics for one to 24 months (10 studies, 1141 children), the risk of symptomatic UTI was not significantly different at any time point. Combined surgical and antibiotic treatment caused a 57% reduction in febrile UTI by five years (2 studies, 449 children: RR 0.43, 95% CI 0.27 to 0.70) but did not decrease the risk of new or progressive renal damage at any time point. Postoperative obstruction was seen in 0% and 7% of children in two surgical studies and 0% in one endoscopic study.

AUTHORS' CONCLUSIONS

Compared with no treatment, use of long-term, low-dose antibiotics did not significantly reduce the number of repeat symptomatic and febrile UTIs in children with VUR. Considerable heterogeneity in the analyses and inclusion of only one adequately blinded study, made drawing firm conclusions challenging. Antibiotic prophylaxis significantly reduced the risk of developing new or progressive renal damage, but assuming an 8% baseline risk, 33 children would need long-term antibiotic prophylaxis to prevent one more child developing kidney damage over the course of two to three years.The added benefit of surgical or endoscopic correction of VUR over antibiotic treatment alone remains unclear. Eight children would require combined surgical and antibiotic treatment to prevent one additional child developing febrile UTI by five years, but it would not cause fewer children developing renal damage.

Imaging strategy for infants with urinary tract infection: a new algorithm

PURPOSE

We analyzed clinical data for prediction of permanent renal damage in infants with first time urinary tract infection.

MATERIALS AND METHODS

This population based, prospective, 3-year study included 161 male and 129 female consecutive infants with first time urinary tract infection. Ultrasonography and dimercapto-succinic acid scintigraphy were performed as acute investigations and voiding cystourethrography within 2 months. Late scintigraphy was performed after 1 year in infants with abnormality on the first dimercapto-succinic acid scan or recurrent febrile urinary tract infections. End point was renal damage on the late scan.

RESULTS

A total of 270 patients had end point data available, of whom 70 had renal damage and 200 did not. Final kidney status was associated with C-reactive protein, serum creatinine, temperature, leukocyturia, non-Escherichia coli bacteria, anteroposterior diameter on ultrasound and recurrent febrile urinary tract infections. In stepwise multiple regression analysis C-reactive protein, creatinine, leukocyturia, anteroposterior diameter and non-E.coli bacteria were independent predictors of permanent renal damage. C-reactive protein 70 mg/l or greater combined with anteroposterior diameter 10 mm or greater had sensitivity of 87% and specificity of 59% for renal damage. An algorithm for imaging of infants with first time urinary tract infection based on these results would have eliminated 126 acute dimercapto-succinic acid scans compared to our study protocol, while missing 9 patients with permanent renal damage.

CONCLUSIONS

C-reactive protein can be used as a predictor of permanent renal damage in infants with urinary tract infection and together with anteroposterior diameter serves as a basis for an imaging algorithm.

DMSA scan for revealing vesicoureteral reflux in young children with urinary tract infection

OBJECTIVES

The objective of this study was to assess the ability of acute dimercaptosuccinic acid (DMSA) scintigraphy for revealing vesicoureteral reflux (VUR) in young children after a first febrile urinary tract infection (UTI).

METHODS

Children aged<or=24 months and were admitted with a first febrile UTI during a 5-year period were evaluated. The ability of acute DMSA scintigraphy to reveal dilating (grades 3-5) or severe (grades 4-5) VUR was assessed by comparing DMSA scan findings with those of voiding cystourethrography.

RESULTS

Of the 296 children included, 46 had dilating and 25 severe VUR. Abnormal DMSA scan results were associated with an odds ratio of 4.36 for dilating and 5.50 for severe VUR. For detecting dilating VUR, the area under the curve (AUC) was 0.68, the positive likelihood ratio (LR) was 2.00, and the negative LR was 0.46; for severe VUR, those values were 0.69, 2.10, and 0.38, respectively. Children with abnormal DMSA scan results combined with abnormal ultrasonography had an odds ratio of 3.60 for dilating and 6.32 for severe VUR. Despite normal findings on both investigations, 12 children had dilating and 4 severe VUR. For dilating VUR, the area under the (AUC) was 0.65, the positive LR was 1.70, and the negative LR was 0.47; for severe VUR, the values were 0.69, 1.90, and 0.29, respectively.

CONCLUSIONS

Our data suggest that acute DMSA scintigraphy has limited overall ability in identifying VUR and should not be endorsed as replacement for voiding cystourethrography in the evaluation of young children with a first febrile UTI.

A guideline for the inpatient care of children with pyelonephritis

BACKGROUND AND OBJECTIVES

Febrile urinary tract infections and pyelonephritis are common in children and frequently lead to hospitalization for management, especially in the child who appears toxic. The American Academy of Pediatrics (AAP) practice parameter on the diagnosis, treatment and evaluation of the initial urinary tract infection in febrile infants and young children provides experience and evidence-based guidelines for the practitioner caring for children between the ages of 2 months to 2 years. No established guideline exists for older children and the AAP guideline does not specifically focus on inpatient care.

METHODS

We conducted a comprehensive review of recently published literature and practice guidelines to develop a consensus on the inpatient diagnosis and management of children with pyelonephritis.

RESULTS

Eight recommendations are proposed for the diagnosis and management, including revised guidelines for the imaging studies postpyelonephritis on the basis of current best evidence.

CONCLUSION

Proper diagnosis of pyelonephritis, timely initiation of appropriate therapy and identification of children at risk for renal injury will help to reduce immediate as well as long-term complications due to chronic kidney disease.

Catheter-free methods for vesicoureteric reflux detection: our experience and a critical appraisal of existing data

In recent years, the exact role of vesicoureteric reflux (VUR) in general has become controversial, though in some groups of children the knowledge of the existence or non-existence of VUR is still a very important issue. The number of techniques available for the assessment of VUR is increasing, and a new classification taking into account their real characteristics (direct/indirect, catheter-using/catheter-free, radiation-giving/radiation-free) has been proposed. The purpose of the following review is to evaluate the currently available evidence supporting the use of various catheter-free methods for VUR detection. We believe that as the clinical role of VUR has been questioned, it is even more important for the method of its detection to be user-friendly as regards catheterisation, radiation and availability. There is still no evidence supporting the assertion that any of the catheter-free methods of VUR detection might be the optimal one for any child. However, there are some groups of children who would benefit from using them. New studies using new, catheter-free methods of VUR detection or a combination of two or more of the methods described may prove useful in improving sensitivity and providing additional data on this important issue.

Is antibiotic prophylaxis effective in preventing urinary tract infections in patients with vesicoureteral reflux?

The main concern in the management of children with vesicoureteral reflux (VUR) is the prevention of urinary tract infections and avoidance of renal damage. Medical management has been recommended or preferentially suggested over surgery in all but a few select clinical situations. Prophylactic antibiotics are prescribed routinely in the management of young children with radiological evidence of VUR following an episode of acute pyelonephritis. Prophylaxis is generally maintained until the VUR resolves spontaneously or is corrected surgically. Although the administration of prophylactic antibiotics has been universal in children with VUR, some authors have reported that long-term antibiotic prophylaxis does not fully prevent urinary tract infections or scarring, that antibiotic-related adverse events are known to occur, and that the incidence of pyelonephritis does not increase in spite of prophylactic antibiotic cessation. Recently, four prospective, randomized, controlled trials of antibiotic prophylaxis for preventing pyelonephritis and renal scarring were reported and some placebo-controlled, double-blind prospective studies are ongoing. The goal of this review is to evaluate the treatment of VUR using antibiotic prophylaxis, and its advantages and disadvantages based on appropriate descriptions and studies in the literature.

Injection volumes of dextranomer/hyaluronic acid are increasing in the endoscopic management of vesicoureteral reflux

PURPOSE

Dextranomer/hyaluronic acid (Deflux) has been increasingly used for the treatment of vesicoureteral reflux (VUR). Experience has shown that injecting more volume of material is necessary to achieve greater success. We evaluate trends in the number of vials being used to treat VUR using a multi-institutional database and data from patients treated at our own institution.

METHODS

Children of age 0-19 years in the Pediatric Health Information System (PHIS) database from 2003 to 2008 were extracted with a VUR diagnosis (ICD-9 593.7x) and subureteric injection procedure code (CPT 52327). We identified children with reflux treated with endoscopic injection at Seattle Children's Hospital from 2005 to 2008. Hospital trends of the number of vials used were evaluated using multivariate linear regression.

RESULTS

From 2003 to 2008, we identified 4,078 endoscopic injection procedures in PHIS. There was a 33% increase in the average number of vials used per patient (p < 0.0001) with more than a threefold increase in the number of patients receiving three or more vials per procedure. All institutions increased the average vials used per patient with the most pronounced increase at the highest-volume centers. These trends were also present in the 186 children treated at our own institution.

CONCLUSION

Over the study period there was an increase in the number of vials of dextranomer/hyaluronic acid being used per patient to treat children with VUR. This practice may improve success rates but will increase the cost of treatment due to the inherent expense of the material.

Investigating febrile UTI in infants: is a cystogram necessary?

OBJECTIVE

Current imaging recommendations for investigating any infantile febrile urinary tract infection (UTI) are ultrasound scan (US), micturating cystourethrogram (MCUG) and dimercaptosuccinic acid (DMSA) scan. The aim of this retrospective cohort study was to determine the need and indications for MCUG in the investigation of a first febrile infantile UTI, as doubts have been raised over its benefit.

PATIENTS AND METHODS

Information on 427 infants who had undergone US, MCUG and DMSA following a first febrile UTI was prospectively recorded. The infants were divided into two groups: A (354) with normal renal US and B (73) with abnormal US. DMSA findings were correlated with findings on MCUG. Main outcome measures were incidence of recurrent UTIs, change in management or intervention as a result of MCUG, and outcome at discharge.

RESULTS

Only 21/354 (6%) infants in Group A had both scarring on DMSA and vesicoureteric reflux (VUR), predominantly low-grade on MCUG. In Group B (abnormal US), 23/73 (32%) had scarring on DMSA and vesicoureteric reflux, predominantly high grade on MCUG. Of the infants with non-scarred kidneys, 73% had dilating reflux. Successful conservative treatment was performed in 423 infants, and 4 infants in Group B required surgery.

CONCLUSION

We recommend US and DMSA in all infantile febrile UTI cases. Where US is normal, MCUG should be reserved for those cases with abnormal DMSA. Where US is abnormal, MCUG should be performed irrespective of findings on DMSA scan. A randomized prospective study is necessary to evaluate this further.

Urinary tract infection in children

INTRODUCTION

Up to 11.3% of girls and 3.6% of boys will have had a urinary tract infection (UTI) by the age of 16 years, and recurrence of infection is common. Vesicoureteric reflux is identified in up to 40% of children being investigated for a first UTI, and is a risk factor for, but weak predictor of, renal parenchymal defects.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatment of acute urinary tract infection in children? What are the effects of interventions to prevent recurrence? We searched: Medline, Embase, The Cochrane Library, and other important databases up to July 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 25 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics (short initial intravenous antibiotics, long initial intravenous antibiotics, initial oral antibiotics, single-dose or single-day courses of oral antibiotics, short courses of oral antibiotics, long courses of oral antibiotics, immediate empirical antibiotics, delayed antibiotics, prolonged delay of antibiotics, prophylactic antibiotics); immunotherapy; surgical correction of minor functional abnormalities; and surgical correction of moderate to severe vesicoureteric reflux.

Predictors of abnormal renal cortical scintigraphy in children with first urinary tract infection: the importance of time factor

INTRODUCTION

We evaluated different factors predicting the development of acute pyelonephritis in Iranian children, with special attention to time factor.

METHODS

One hundred nineteen patients (93 females and 26 males; age = 32.6 ± 30.8 months) with first urinary tract infection (UTI) were evaluated. None had previous urological problems. Prior to antibiotic therapy blood samples were gathered for laboratory evaluation. Vital signs on admission were measured. Clinical and laboratory indices, including therapeutic delay time (TDT) and therapeutic response time (TRT), were measured. Most patients were evaluated with renal ultrasound in the first three days following admission. All patients underwent dimercaptosuccinic acid (DMSA) renal scintigraphy and 71 were assessed for vesicoureteral reflux (VUR).

RESULTS

DMSA scans were abnormal in 77 cases, of which 11 cases had bilateral renal involvement. Mean values for TDT, TRT, leukocyte count (LC), absolute neutrophil count (ANC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were 74.1 h, 39.6 h, 15725 ± 6682 mm(-3), 10772 ± 6458 mm(-3), 51.9 ± 32.5 mm, and 27.3 ± 25.1 mg l(-1), respectively. VUR was present in 29 of 142 evaluated renal units.

CONCLUSION

TDT ≥ 48 h, TRT ≥ 24 h, axillary temperature ≥ 39°C, LC ≥ 13500 mm(-3), and age ≥ 18 months predicted abnormal DMSA scan in patients with first episode of UTI. Considerably higher TDT and TRT values of the current study compared to previous ones suggests the more important role of time factor in predicting abnormal DMSA findings in a developing country than in developed ones.

Could prophylactic antibiotics be stopped in patients with history of vesicoureteral reflux?

OBJECTIVE

To compare the incidence and type of urinary tract infection (UTI) in patients with primary vesicoureteral reflux (VUR) diagnosed after a febrile UTI while they were on prophylactic antibiotics (PA) and after stopping PA.

MATERIALS AND METHODS

Criteria to discontinue PA were: no UTI during 12+ or more months on PA, old enough to communicate UTI symptoms, potty trained and absence of risk factors for UTI. Patients with at least 1 year of follow up without PA were included (n=77). We recorded: age at which PA was indicated and stopped, time on and off PA, incidence and type of UTI (cystitis vs acute pyelonephritis (APN)), and renal scan results.

RESULTS

PA was started and stopped at a mean age of 18.5 and 61 months, respectively. Mean time on PA was 39 months (range 12-95): 25 patients had 44 UTI episodes (0.17 episodes/patient/year), and 31 (70%) of them were APN. Mean time of antibiotics was 44.5 months (range 12-162): 13 patients had 24 UTI episodes (0.08 episodes/patient/year), eight (33%) of which were APN (P<0.05). A renal scan was performed in 71 patients after the index infection and repeated in 12. Two patients lost renal function while still on PA.

CONCLUSION

Discontinuing PA in patients with history of VUR is a safe practice and should be considered as a management option.

Controversies in the management of vesicoureteral reflux: the rationale for the RIVUR study

The current management of vesicoureteral reflux (VUR) focuses on the prevention of urinary tract infections (UTI), with curative surgery being limited to those children that fail conservative measures. This is based on the assumption that UTIs are preventable with the use of prophylatic antibiotics, leading to reduction of renal scarring, and the possibility that VUR in children can resolve spontaneously.

METHODS

Review of the recent literature has demonstrated a growing concern that antibiotic prophylaxis may not lead to prevention of UTIs. Additionally, data indicate that renal scarring may not be preventable with antibiotic prophylaxis or even surgical correction of VUR. An overview of all of the current controversies is presented in this paper.

RESULTS

Does antibiotic prophylaxis lead to reduction in UTIs in children with VUR? To address this question, the National Institutes of Health have developed a randomized placebo-controlled study of children with VUR (the RIVUR Study), identified following the development of a UTI.

CONCLUSIONS

There are far reaching consequences of the results of the RIVUR Study. If antibiotic prophylaxis does not prevent UTI in children with VUR, or lead to reduction in renal scarring, does identification of VUR provide any benefits? Perhaps appropriate treatment of UTI may be all that is necessary for preserving renal function. Final answers will have to wait until the completion of this study.

Update on childhood urinary tract infection and vesicoureteral reflux

Urinary tract infection (UTI) is a leading cause of serious bacterial infection in young children. Vesicoureteral reflux (VUR), a common pediatric urologic disorder, is believed to predispose to UTI, and both are associated with renal scarring. The complex interaction of bacterial virulence factors and host defense mechanisms influence renal damage. However, some renal parenchymal abnormalities associated with VUR are noninfectious in origin. Long-term, renal parenchymal injury may be associated with hypertension, pregnancy complications, proteinuria, and renal insufficiency. Optimal management of VUR and UTI is controversial because of the paucity of appropriate randomized controlled trials; there is a need for well-designed studies. The recently launched Randomized Intervention for children with VesicoUreteral Reflux (RIVUR) study hopefully will provide insight into the role of antimicrobial prophylaxis of UTI in children with VUR.