Efficacy of antibiotic prophylaxis in children with vesicoureteral reflux: systematic review and meta-analysis

PIC cystography in occult vesicoureteral reflux: A systematic review highlighting its utility in children with recurrent urinary tract infections and normal VCUG

BACKGROUND

Vesicoureteral reflux (VUR) affects 1-2% of children, predisposing them to pyelonephritis, renal scarring, and reflux nephropathy. Treatment aims to prevent febrile urinary tract infections (f-UTI) and long-term sequelae. While guidelines differ, the current consensus proposes individual risk-stratification and subsequent management strategies. Here, we systematically analyzed the current literature on Positional Instillation of Contrast Cystography (PIC) for individualized diagnostics in patients with recurrent f-UTIs.

OBJECTIVE

We present a comprehensive qualitative and quantitative synthesis. Outcomes were: 1. the ability of PIC to predict VUR in patients with negative voiding cystographies (VCUG), 2. the ability of PIC to predict occult contralateral VUR, 3. the correlation of occult VUR in PIC with dimercaptosuccinic acid (DMSA) scan findings, and 4. the incidence of postoperative f-UTI in children treated for occult VUR picked up on PIC.

STUDY DESIGN

We conducted a systematic review following the PRISMA guidelines, applying the following inclusion criteria: Children with occult VUR in PIC with negative VCUG.

RESULTS

We included nine studies with 496 symptomatic patients with a mean age of 6.8 years, published between 2003 and 2021. PIC detected VUR in 73% of patients. Out of them, 81% had low-grade and 19% high-grade VUR. Occult contralateral VUR was present in 41% children. The presence of renal scars on DMSA scan was 1.39 times more likely with occult VUR on PIC. 85% of patients did not experience recurrent f-UTIs after PIC and subsequent treatment.

DISCUSSION

PIC can detect occult VUR in patients with recurrent f-UTIs in whom VCUG is negative. However, we recommend a cautious approach in the use of PIC in clinical practice until further prospective studies confirm the validity of our outcome measures.

CONCLUSION

Identification, risk stratification, and prompt action are central in managing VUR. PIC can be helpful in identifying VUR in patients with recurrent f-UTI.

Antimicrobial resistance of breakthrough urinary tract infections in young children receiving continual antibiotic prophylaxis

Continual antibiotic prophylaxis (CAP) can reduce the risk of recurrent UTI (rUTI). However, antimicrobial resistance in subsequent UTIs is a concern. This study aimed to explore antimicrobial resistance in young children prescribed CAP for rUTIs. A retrospective review of patient records/microbiology results was undertaken for children < 2 years of age, on CAP, with 2-3 clean catch/mid-stream/supra-pubic aspirate urine cultures with a pure growth of bacteria, between January 2017 and December 2019. One hundred twenty-four urine specimens from 54 patients (26 (48%) males, median age 6 months) were analysed. CAP prescribed was trimethoprim in 37 (69%), cefalexin in 11 (29%), and nitrofurantoin in 6 (11%). Based on antimicrobial susceptibility of the index UTI within the study period, 41 patients (76%) grew organisms on urine culture classified as sensitive and 13 (24%) resistant. Thirty-five (65%) children had congenital anomaly of the kidneys and urinary tract (CAKUT); they were more likely to be in the resistant group (P = 0.032). Escherichia coli (37/54, 69%) was the commonest index uropathogen. The resistant group had a higher proportion of non-E. coli index UTI pathogens (P = 0.098). Breakthrough UTI with a CAP-resistant organism was more likely in the resistant group (P = 0.010). Age, sex, and kidney scarring on DMSA (dimercaptosuccinic acid) scan were not significantly different between groups.  Conclusion: Over a 3-year period, the proportion of children on CAP with resistant organism UTI doubled and resistant infections were more likely in children with CAKUT. Development of non-antimicrobial prophylaxis options is required. What is Known: • Recurrent urinary tract infections are common in children, particularly in those with underlying anatomical abnormalities of the kidneys and urinary tract. • Continuous antibiotic prophylaxis is used frequently in these children, however there is a lack of consensus on whether the potential benefits of CAP outweigh the harms. What is New: • This study adds further evidence towards the consequences of using continuous antibiotic prophylaxis in recurrent UTI; specifically, a 2-fold increase in antimicrobial resistance was seen in subsequent UTIs following long-term use of CAP, providing further vigour for the need for non-antibiotic alternatives.

Antibiotic Prophylaxis for the Prevention of Urinary Tract Infections in Children: Guideline and Recommendations from the Emilia-Romagna Pediatric Urinary Tract Infections (UTI-Ped-ER) Study Group

Background: Urinary tract infection (UTI) represents one of the most common infectious diseases and a major cause of antibiotic prescription in children. To prevent recurrent infections and long-term complications, low-dose continuous antibiotic prophylaxis (CAP) has been used. However, the efficacy of CAP is controversial. The aim of this document was to develop updated guidelines on the efficacy and safety of CAP to prevent pediatric UTIs. Methods: A panel of experts on pediatric infectious diseases, pediatric nephrology, pediatric urology, and primary care was asked clinical questions concerning the role of CAP in preventing UTIs in children. Overall, 15 clinical questions were addressed, and the search strategy included accessing electronic databases and a manual search of gray literature published in the last 25 years. After data extraction and narrative synthesis of results, recommendations were developed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) methodology. Results: The use of CAP is not recommended in children with a previous UTI, with recurrent UTIs, with vesicoureteral reflux (VUR) of any grade, with isolated hydronephrosis, and with neurogenic bladder. CAP is suggested in children with significant obstructive uropathies until surgical correction. Close surveillance based on early diagnosis of UTI episodes and prompt antibiotic therapy is proposed for conditions in which CAP is not recommended. Conclusions: Our systematic review shows that CAP plays a limited role in preventing recurrences of UTI in children and has no effect on its complications. On the other hand, the emergence of new antimicrobial resistances is a proven risk.

Prescribed daily-dose-based metrics of oral antibiotic use for hospitalized children in Japan

OBJECTIVE

Defined daily-dose (DDD)-based metrics are frequently used to measure antibiotic consumption. However, they are unsuitable for the pediatric population because they are defined using the maintenance dose for 70-kg adults. Moreover, children have large body weight variations. We assessed the prescribed daily dose (PDD) and PDD-based metrics of oral antibiotics for children to develop an alternative to DDD-based metrics in Japan.

DESIGN

We performed observational study using data from the Japanese administrative claims database between April 2018 and March 2019.

METHODS

Of 453,001 patients (aged 1 month-15 years), 564,326 admissions to 1,159 hospitals were included. We showed the median PDD (mg/day and mg/kg/day) and PDD-based metrics for 8 antibiotics for each age category (1 month to <1 year old and 1-6, 7-12, and 13-15 years old). We also assessed the relationship between PDD-based metrics and days of therapy (DOT)-based metrics using a scatter plot and correlation.

RESULTS

In total, 86,389 patients (19.1%) were prescribed oral antibiotics; amoxicillin, macrolides, and third-generation cephalosporins were the most common. The PDD (mg/day) for each antibiotic increased with age to 7-12 years old, when an adult dose was reached. The PDD (mg/kg/day) decreased with age to 13-15 years old, due to increasing body weight. The relationship between PDD per 1,000 patient days and DOT per 1,000 patient days differed depending on the antibiotic.

CONCLUSIONS

PDD-based metrics stratified by age could characterize antibiotic consumption, even with body-weight variations. Therefore, PDD-based metrics, in addition to DOT-based metrics, are helpful benchmarks for antibiotic use in children.

A Systematic Review of the (Un)known Host Immune Response Biomarkers for Predicting Recurrence of Urinary Tract Infection

Recurrent urinary tract infections (rUTI) represent a major healthcare and economic burden along with a significant impact on patient’s morbidity and quality of life, even in the absence of well-known risk factors, such as vesicoureteral reflux. Despite numerous attempts to find a suitable therapeutic option, there is no clear benefit of any currently available intervention for prevention of UTI recurrence and its long-term consequences such as hypertension, renal scarring and/or insufficiency. The common treatment practice in many centers around the globe involves the use of continuous low-dose antibiotic prophylaxis, irrespective of various studies indicating increased microbial resistance against the prophylactic drug, leading to prolonged duration and escalating the cost of UTI treatment. Moreover, the rapid appearance of multi-drug resistant uropathogens is threatening to transform UTI to untreatable disease, while impaired host-microbiota homeostasis induced by a long-term use of antibiotics predisposes patients for various autoimmune and infectious diseases. New biomarkers of the increased risk of UTI recurrence could therefore assist in avoiding such outcomes by revealing more specific patient population which could benefit from additional interventions. In this light, the recent findings suggesting a crucial role of urothelial innate immunity mechanisms in protection of urinary tract from invading uropathogens might offer new diagnostic, prognostic and even therapeutic opportunities. Uroepithelial cells detect uropathogens via pattern recognition receptors, resulting in activation of intracellular signaling cascade and transcription factors, which ultimately leads to an increased production and secretion of chemokines, cytokines and antimicrobial peptides into the urinary stream. Emerging evidence suggest that the disturbance of a single component of the urinary tract innate immunity system might increase susceptibility for rUTI. The aim of the current review is to update clinicians and researchers on potential biomarkers of host immune response alterations predisposing for rUTI and propose those well worth exploring further. For this purpose, over a hundred original papers were identified through an extensive PubMed and Scopus databases search. This comprehensive review might enrich the current clinical practice and fill the unmet clinical needs, but also encourage the development of therapeutic agents that would facilitate urinary bacterial clearance by enhancing the host immune response.

Evaluation of renal function and scars in children with primary vesicoureteral reflux

OBJECTIVE

To evaluate growth, glomerular and tubular function, renal damage, scars in children affected by primary VUR.

METHOD

We retrospectively evaluated the clinical records of our Unit from January 2006 to September 2020. For each patient we evaluated growth, laboratoristic and scintigraphic glomerular and tubular function, renal damage and collective system urodynamics at baseline and at the last visit.

RESULT

We enrolled 41 patients affected by primary VUR and treated with continuous antibiotic prophylaxis. Glomerular function and urodynamics did not change over time. EFNa directly correlated with weight (r 0.44 p 0.004) and TRP inversely correlated with severity of reflux (r -0.32, p 0.04). Female sex was associated to nephrolithiasis (OR 17.0, p 0.02) and proteinuria (at T0 OR 5.8 p 0.03 at T1 OR 5.8, p 0.03). Daily proteinuria increased with age (r 0.66, p <0.0001 at T0 and r 0.44 p 0.004 at T1) while protein-to-creatinine ratio decreased. Renal scars at T0 inversely correlated with glomerular and tubular function at T1 but they did not correlate with severity or laterality of reflux.

CONCLUSION

Even if renal function remains stable through years, it is critical to identify the subjects with significant congenital renal damage.

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.

Clinical guidelines of UTIs in children: quality appraisal with AGREE II and recommendations analysis

OBJECTIVE

To explore the current Chinese and English guidelines of urinary tract infection (UTI) in children and provide a summary of the recommendations of the guidelines.

METHODS

An electronic search was conducted on databases, including Pubmed, SinoMed, Wangfang Data, CHKD,VIP, NICE, WHO, GIN and Medliveto retrieve data of the clinical practice guidelines on UTI from the establishment of the database to June 2020. Four assessors assessed the quality of guidelines using the Appraisal of Guidelines for Research & Evaluation II (AGREE II) and evaluated the specific recommendations in guidelines.

RESULTS

(1) Nine guidelines including two from the USA (AAP and A guideline for the inpatient care of children with pyelonephritis) and the remaining from EAU/ESPU, SINEPE, KHA-CARI, CPS, ISPN, NICE and CMA-CSP were explored. (2) The AGREE II evaluation demonstrated higher scores of UTI guidelines in terms of 'scope and purpose' (72.99%±11.19%) and 'clarity of presentation' (75.62%±7.75%), whereas the average scores were lower in the aspect of 'stakeholder involvement' (35.49%±14.41%), 'rigour of development' (37.05%±10.05%), 'applicability' (37.75%±11.98%) and 'editorial independence' (43.06%±48.14%). The average scores of the guidelines were as follows: SINePe (72.57%), CMA-CSP (62.96%), EAU/ESPU (59.61%), AAP (56.86%), NICE (47.54%), CPS (40.93%), KHA-CARI (38.86%), ISPN (38.63%) and A guideline for the inpatient care of children with pyelonephritis (34.72%). (3) All the selected guidelines basically reached a consensus on urine sample retention methods in older children, the antibiotic treatment course and renal and bladder ultrasonography application but lacked a conclusion on the determination of urine culture results, the choice of voiding cystourethrography and Tc-99mdimercaptosuccinicacid, and antibiotic prophylaxis.

CONCLUSION

There remains a need to improve the quality of guidelinesfor UTI in clinical practice. Existing controversies on the current guidelines of UTI in some recommendations warrant further exploration to provide more evidence on formulating more unified and practical guidelines in the future.

ETHICS AND DISSEMINATION

No ethical approval is required for this research, as it did not include patients or patient data.

Urinary Tract Dilation in the Fetus and Neonate

Urinary tract dilation (UTD), previously known as hydronephrosis, is the most common congenital condition identified on prenatal ultrasonography. UTD can be physiologic and resolve spontaneously or can be caused by various congenital anomalies of the urinary tract, which can lead to renal failure if not treated properly. In 2014, a multidisciplinary consensus group established UTD definitions, a classification system, and a standardized scheme for perinatal evaluation. Various imaging modalities are available to help diagnose the cause of UTD in fetuses and neonates and to help identify those patients who may benefit from fetal or early postnatal intervention. In this article, we will review the diagnosis and quantification of antenatal and postnatal UTD based on the UTD classification system, outline the imaging studies available to both evaluateUTD and determine its cause, briefly review the most common causes of UTD in the fetus and neonate, outline management strategies for UTD including the role for fetal intervention and prophylactic antibiotics, and report on the outcome and prognosis in patients with UTD.

Does Early Upper Tract Diversion and Delayed Undiversion in Megaureters Secondary to Severe Posterior Urethral Valves Lead to Better Renal Outcomes?

Background

There are conflicting reports for the management of severe posterior urethral valve (PUV) after ablation. The primary objective was to assess the renal outcomes using the estimated glomerular filtration rate (eGFR) and secondary outcomes in severe PUVs who underwent early partially diverting reduction ureterostomy (PDRU) and a delayed undiversion protocol.

Materials and Methods

This 10-year retrospective study reviewed the records of 1094 boys with PUV, where severe PUV cases were treated with early PDRU (324 surgeries). We then analyzed those patients who completed the early diversion and delayed undiversion protocol. The long-term renal outcomes using eGFR and antero-posterior diameter (APD) were compared at various time points using appropriate statistical methods.

Results

Of the 171 severe PUV patients who underwent PDRU, 31 completed undiversion and 26 (47 renal units) were analyzed after exclusions. The mean age (standard deviation) at presentation was 1.46 ± 4.1 months. Thirty-two units were refluxing and 15 were nonrefluxing megaureters. PDRU was closed at a mean age of 3.9 years and had a mean duration of follow-up of 6.4 years. The mean eGFR increased from a minimum of 10.78 ± 10.25 at baseline and remained stable at 28.69 ± 18.89 after closure of both stoma. Similarly, mean APD decreased from 12.07 ± 6.79 at the diagnosis to 7.00 ± 6.20. Three patients (3 renal units) required revision of the stoma for stenosis and 1 patient had a parastomal hernia that was repaired at the time of undiversion.

Conclusions

In severe PUVs, early PDRU with delayed undiversion is a reliable surgical option that may ensure better renal outcomes in the long-term. Nonrefluxing renal units recover better than the refluxing. APD measurements also are shown to improve favorably.

Risk factors for breakthrough urinary tract infection in children with vesicoureteral reflux receiving continuous antibiotic prophylaxis

BACKGROUND

To investigate the risk factors for breakthrough urinary tract infection (BT-UTI) in children with vesicoureteral reflux (VUR) receiving continuous antibiotic prophylaxis (CAP).

METHODS

This was a single-centre cohort study (January 2016 to December 2019). The clinical data of 256 children with grade I-V VUR receiving CAP were analysed. In this study, exposure variables were sex, younger age at the initial diagnosis of UTI ≤12 months, high-grade VUR, bilateral VUR, aetiology, presence of renal scarring at the initial diagnosis, presence of renal function impairment at the initial diagnosis, ultrasound abnormalities, antibiotic used and bladder and bowel dysfunction (BBD). Outcome was BT-UTI.

RESULTS

BT-UTI occurred in 81 out of 256 children with grade I-V VUR who received CAP, an incidence of 31.64%. Univariate analysis showed that younger age at the initial diagnosis of UTI (≤12 months), bilateral VUR, renal scarring on the dimercaptosuccinic acid (DMSA) scan at the initial diagnosis of UTI and BBD were correlated with the occurrence of BT-UTI. Multivariate analysis showed that younger age at the initial diagnosis of UTI (≤12 months) [hazard ratio (HR): 4.629; 95% confidence interval (CI): 1.302-16.462], bilateral VUR (HR: 2.078; 95% CI: 1.084-4.022) and BBD (HR: 3.194; 95% CI: 1.243-8.206) were independent risk factors for the occurrence of BT-UTI.

CONCLUSIONS

For VUR children receiving CAP, younger age at the initial diagnosis of UTI (≤12 months), bilateral VUR, and BBD were independent risk factors for the occurrence of BT-UTI.

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.

Contemporary Management of Urinary Tract Infection in Children

Urinary tract infection (UTI) is common in children, and girls are at a significantly higher risk, as compared to boys, except in early infancy. Most cases are caused by Escherichia coli Collection of an uncontaminated urine specimen is essential for accurate diagnosis. Oral antibiotic therapy for 7 to 10 days is adequate for uncomplicated cases that respond well to the treatment. A renal ultrasound examination is advised in all young children with first febrile UTI and in older children with recurrent UTI. Most children with first febrile UTI do not need a voiding cystourethrogram; it may be considered after the first UTI in children with abnormal renal and bladder ultrasound examination or a UTI caused by atypical pathogen, complex clinical course, or known renal scarring. Long-term antibiotic prophylaxis is used selectively in high-risk patients. Few patients diagnosed with vesicoureteral reflux after a UTI need surgical correction. The most consequential long-term complication of acute pyelonephritis is renal scarring, which may increase the risk of hypertension or chronic kidney disease later in life. Treatment of acute pyelonephritis with an appropriate antibiotic within 48 hours of fever onset and prevention of recurrent UTI lowers the risk of renal scarring. Pathogens causing UTI are increasingly becoming resistant to commonly used antibiotics, and their indiscriminate use in doubtful cases of UTI must be discouraged.

Brazilian consensus on vesicoureteral reflux-recommendations for clinical practice

Introduction

Vesicoureteral Reflux (VUR) is characterized by a retrograde flow of urine from the bladder into the ureters and kidneys. It is one of the most common urinary tract anomalies and the major cause of urinary tract infection (UTI) in the first years of life. If not properly diagnosed and treated can lead to recurrent UTI, renal scar and, in severe cases, to end stage renal disease. Despite recent advances in scientific and technological knowledge, evaluation and treatment of VUR is still controversial and there is still considerable heterogeneity in evaluation methods and therapeutic approaches. The aim of the present consensus is to give a practical orientation on how to evaluate and treat VUR.

Methods

The board of Pediatric Urology of the Brazilian Society of Urology joined a group of experts and reviewed all important issues on Vesicoureteral Reflux evaluation and treatment and elaborated a draft of the document. On November 2017 the panel met to review, discuss and write a consensus document.

Results and Discussion

Vesicoureteral Reflux is a common and challenging problem in children. Children presenting with Vesicoureteral Reflux require careful evaluation and treatment to avoid future urinary tract infections and kidney scars. The panel addressed recommendations on up to date choice of diagnosis evaluation and therapies.

Medicinal plants consumption against urinary tract infections: a narrative review of the current evidence

INTRODUCTION

Urinary tract infections (UTIs) are usual diseases caused by different strains of microorganisms. Many antibiotics have been applied for the treatment of these infections. However, the development of multidrug-resistant strains is a major problem in these treatments. As alternative complementary agents, several medicinal plants are often used to prevent and/or treat these diseases.

AREAS COVERED

This review summarized the current evidence about the efficacy of medicinal plants' consumption to prevent and/or co-treat UTIs. The most precise scientific databases, e.g. Medline, Scopus, and Web of Science were comprehensively searched, using relative keywords to identify the relative in vivo and ex vivo animal and human studies.

EXPERT OPINION

Current studies supported evidence for potential benefit overall concerning medicinal plants' consumption against UTIs by preventing bacterial adherence and inhibiting inflammation cascades through responding immunologically to bacteria invasion. However, most of the current evidence have been focused on in vivo and ex vivo animal studies, while human studies are currently limited and did not focus on a specific medicinal plant. Thus, well-designed clinical trials for long study periods focused on individual medicinal plants are intensely recommended to delineate their effectiveness on the prevention and/or co-treatment of UTIs.

Antibiotic prophylaxis for prevention of urinary tract infections in the first year of life in children with vesicoureteral reflux diagnosed in the workup of antenatal hydronephrosis: a systematic review

BACKGROUND

Children with antenatal hydronephrosis (ANH) diagnosed with postnatal asymptomatic vesicoureteral reflux (VUR) are thought to be at higher risk of urinary tract infection (UTI). As such, continuous antibiotic prophylaxis (CAP) is empirically recommended until age of toilet training; however, there are limited data to support this. The objective of this systematic review was to summarize the existing data and compare UTI rates in infants with asymptomatic VUR on CAP during the first year of life, to those not on CAP. Secondary objectives were to determine associated risk factors with UTI development.

METHODS

A systematic search of all relevant studies and abstracts was conducted using 4 electronic databases by utilizing appropriate key words by an expert hospital librarian. Eligible studies included children with prenatal hydronephrosis, asymptomatic VUR with or without CAP, and reported on development of UTI in the first year.

RESULTS

Of 6903 citations screened, 18 were selected, giving a total population of 829 (69.4% male, median age 57 days) who met the inclusion criteria. Most studies were retrospective and of low-quality evidence. Overall, 15.4% of patients developed at least one breakthrough UTI and females had a higher risk of UTI (odds ratio (OR) 2.3, 95% CI 1.1-4.7). Comparison with children not taking CAP was not readily reported, and meta-analysis could not be completed.

CONCLUSIONS

Randomized controlled trials and standardized reporting of clinical variables are required to understand the protective effect of antibiotic prophylaxis in this cohort.

Proprietary non-animal stabilized hyaluronic acid/dextranomer gel (NASHA/Dx) for endoscopic treatment of grade IV vesicoureteral reflux: Long-term observational study

BACKGROUND

Since 1993, children aged >1 year with persistent grade III-V vesicoureteral reflux (VUR) and febrile urinary tract infections (UTIs) attending Uppsala University Hospital have undergone endoscopic injection with proprietary non-animal stabilized hyaluronic acid/dextranomer gel (NASHA/Dx; Deflux®).

OBJECTIVE

Investigate long-term incidence of UTI, bladder dysfunction, ureteral reimplantation and overall clinical findings following endoscopic injection of NASHA/Dx.

STUDY DESIGN

Children with grade IV VUR diagnosed by voiding cystourethrogram (VCUG) and dilating VUR persisting for >1 year were included in this study. 15-25 years after endoscopic treatment, patients' hospital charts were studied. Information on bladder function and UTIs was obtained via questionnaire, 8-18 years after endoscopic treatment.

RESULTS

185 patients (69 boys, 116 girls) were included in the study; 237 grade IV VUR ureters were treated. All study patients were diagnosed with VUR after a febrile UTI (i.e. pyelonephritis). According to the last voiding cystourethrogram, 69% of ureters showed a positive response (VUR grade 0-I), 7% had VUR grade II and 23% had VUR grade ≥ III. 46 patients (25%) required ureteral reimplantation during follow-up. Among patients treated during the second 5-year period compared with the first (1998-2003 versus 1993-1998), there was a significant decrease in the rate of ureteral reimplantation (31% vs 16%; p = 0.0365). This difference may be attributable to developments over time in the injection technique. UTIs occurred in 30 patients (21% of the evaluable population): 28 females and 2 males. Febrile UTIs were reported in 14 patients (10%), all females. Forty-nine patients (34%) had bladder problems (e.g. underactivity, overactivity, incontinence). Five patients underwent ureteral reimplantation 'late', 6-10 years after the last endoscopic injection. In one male patient, calcification around the NASHA/Dx implantation site was observed during routine examination 2 years after endoscopic treatment; no intervention was required. No safety issues were observed in the remaining 97% of the study population.

CONCLUSIONS

This study represents the longest published follow-up of Grade IV VUR patients undergoing endoscopic treatment. Three-quarters of patients did not need ureteral reimplantation. Optimal injection technique and higher injection volume were associated with a reduced ureteral reimplantation rate. Treatment with NASHA/Dx was durable and well tolerated: long-term risks of UTI, bladder dysfunction and recurrent VUR were low.

Updated Italian recommendations for the diagnosis, treatment and follow-up of the first febrile urinary tract infection in young children

AIM

Our aim was to update the recommendations for the diagnosis, treatment and follow-up of the first febrile urinary tract infection in young children, which were endorsed in 2012 by the Italian Society of Pediatric Nephrology.

METHODS

The Italian recommendations were revised on the basis of a review of the literature published from 2012 to October 2018. We also carried out an ad hoc evaluation of the risk factors to identify children with high-grade vesicoureteral reflux or renal scarring, which were published in the previous recommendations. When evidence was not available, the working group held extensive discussions, during various meetings and through email exchanges.

RESULTS

Four major modifications have been introduced. The method for collecting urine for culture and its interpretation has been re-evaluated. We have reformulated the algorithm that guides clinical decisions to proceed with voiding cystourethrography. The suggested antibiotics have been revised, and we have recommended further restrictions of the use of antibiotic prophylaxis.

CONCLUSION

These updated recommendations have now been endorsed by the Italian Society of Pediatric Nephrology and the Italian Society for Pediatric Infectivology. They can also be used to compare other recommendations that are available, as a worldwide consensus in this area is still lacking.

Cost-Effectiveness of Screening Ultrasound after a First, Febrile Urinary Tract Infection in Children Age 2-24 Months

OBJECTIVE

To estimate the cost-effectiveness of routine, screening renal bladder ultrasound (RBUS) for children age 2-24 months after a first febrile urinary tract infection (UTI), as recommended by the American Academy of Pediatrics.

STUDY DESIGN

We developed a decision analytic model that simulates a population of children after a first febrile UTI. The model incorporates the diagnostic utility of RBUS to detect vesicoureteral reflux and genitourinary anomalies. We adopted a health-system perspective, 5-year horizon, and included 1-way and 2-way sensitivity analyses. Costs were inflated to 2018 US dollars, and our model incorporated a 3% discounting rate. We compared routine RBUS after first, febrile UTI compared with routine RBUS after second UTI (ie, control arm). Our main outcomes were recurrent UTI rate and incremental cost per quality-adjusted life-year (QALY).

RESULTS

Among children 2-24 months after a first febrile UTI, RBUS had an overall accuracy (true positives + true negatives) of 64.4%. The recurrent UTI rate in the intervention arm was 19.9% compared with 21.0% in the control arm. Thus, 91 patients would need to be screened with RBUS to prevent 1 recurrent UTI. RBUS increases QALYs by +0.0002 per patient screened, corresponding to an incremental cost-effectiveness ratio of $803 000/QALY gained. In the RBUS arm, 20.6% of children would receive unnecessary voiding cystourethrograms compared with 12.2% of children in the control group.

CONCLUSIONS

Screening RBUS after a first, febrile UTI in children age 2-24 months does not meet cost-effectiveness guidelines. Our findings support deferred screening until a second UTI.

Current status of long-term antibiotic prophylaxis for urinary tract infections in children: An antibiotic stewardship challenge

Recurrent urinary tract infections (UTIs) in children are associated with development of pyelonephritis and renal scarring. Traditionally, continuous antibiotic prophylaxis (CAP) has been used to prevent recurrent UTI. Recent studies have challenged the efficacy of CAP for preventing renal scarring and have raised concerns about inducing bacterial resistance. This review focuses on studies published between January 2000 and April 2019 and evaluates the use of CAP in children for avoiding recurrent UTIs and renal scarring. A systematic literature search was carried out using the following search terms and related medical subject headings in the MEDLINE electronic database: ‘urinary tract infection’, ‘antimicrobial/antibiotic prophylaxis’, and ‘children/pediatrics’. Randomized clinical trials (RCTs), original research articles, guidelines, systematic reviews, and meta-analyses describing antibiotic prophylaxis for UTIs were included. A total of 34 RCTs, 9 systematic reviews, and 3 guidelines describing antibiotic prophylaxis were included in this review. The efficacy of CAP for preventing recurrent UTI remains unclear due to non-generalizability of results obtained from suboptimally designed clinical trials. CAP has not been proven as beneficial for preventing new renal scarring in children. Additionally, CAP is associated with increased risk of multidrug resistant infections in children. No conclusive evidence can be drawn from the available clinical data to support routine use of CAP for prevention of renal scarring. Accumulation of evidence from additional well designed studies may result in different conclusions in the future. It is important to identify specific risks for recurrent UTI and ensuing renal injury to ensure more judicious use of CAP.

Primary vesicoureteral reflux; what have we learnt from the recently published randomized, controlled trials?

In recent years, progress has been made on understanding the relationship between vesicoureteral reflux (VUR) and urinary tract infection (UTI). The findings on recent prospective, randomized, controlled studies have questioned the conventional VUR clinical significance and, therefore, have challenged the traditional diagnostic and therapeutic recommendations. These new studies have redefined the pathogenic role of vesicoureteral reflux in UTI as well as have disputed the routine use of urinary antibiotic prophylaxis to prevent UTI and renal damage in VUR patients. The time to overinvestigate and treat the vast majority of otherwise healthy children who have an uncomplicated UTI with long-term antibiotic prophylaxis seems to be over. Is there a role of severe VUR in the development of chronic renal disease and renal failure? New ideas are needed to answer these questions with the goal to avoid repeating past mistakes when therapeutic choices were based on expert opinions rather than facts.

Antimicrobial prophylaxis for urinary tract infections: implications for adherence assessment

BACKGROUND

Continuous antimicrobial prophylaxis (prophylaxis) is associated with a reduction in recurrent urinary tract infections in children with vesicoureteral reflux. However, adherence to daily medications has been shown to be poor.

OBJECTIVE

To determine patient/caregiver factors associated with non-adherence and to determine whether adherence alters the effect of prophylaxis on recurrent UTIs and renal scarring.

STUDY DESIGN

We conducted a secondary analysis of the Randomized Intervention for Children with Vesicoureteral Reflux trial. We stratified adherence scores into quartiles to assess trends within the data. We assessed predictors of non-adherence using ordinal logistic regression. We then examined the efficacy of prophylaxis stratified by adherence quartiles.

RESULTS

Six hundred patients were included in the analysis. The quartiles of adherence were as follows: 1st quartile-0-70% adherence; 2nd quartile-71-91% adherence; 3rd quartile-92-96% adherence; and 4th quartile->96% adherence. Neither demographic factors nor disease severity was associated with non-adherence. In the subanalysis of patients who were toilet trained at baseline, increasing bladder and bowel dysfunction (BBD) symptom score was associated with non-adherence (adjusted odds ratio, aOR = 1.1, 95% confidence interval [CI] 1.0-1.2). Patients least adherent were 2.5 times more likely (95%CI 1.1-5.6) to have a recurrent UTI compared with patients most adherent. After controlling for treatment arm, age, sex, degree of reflux, BBD, and number of UTIs, patients least adherent (taking the study medication less than <70% of the time) were at highest risk for renal scarring (aOR = 24.2, 95%CI 3.0-197). In contrast, among the most adherent quartile, the probability of renal scarring was highest in those assigned prophylaxis (16.2% compared with 1.7% in those most adherent to placebo).

CONCLUSIONS

Adherence is distinctly related to clinical outcomes in children with VUR. Non-adherence is common and represents a distinct clinical entity that is associated with renal scarring. Adherence should be assessed in prophylaxis management algorithms.

Susceptibility of the Index Urinary Tract Infection to Prophylactic Antibiotics Is a Predictive Factor of Breakthrough Urinary Tract Infection in Children with Primary Vesicoureteral Reflux Receiving Continuous Antibiotic Prophylaxis

BACKGROUND

Few studies have reported on breakthrough urinary tract infection (UTI) associated with the susceptibility of index UTI to prophylactic antibiotics in children with primary vesicoureteral reflux (VUR) receiving continuous antibiotic prophylaxis (CAP). We assessed the impact of the susceptibility of index UTI to prophylactic antibiotics in breakthrough UTIs in children with primary VUR receiving CAP.

METHODS

We retrospectively reviewed the medical records of 81 children with primary VUR who were diagnosed after febrile or symptomatic UTI and subsequently received trimethoprim-sulfamethoxazole (TMP-SMX) as CAP between January 2010 and December 2013. We allocated children to a susceptible group or a resistant group based on the susceptibility of index UTI to TMP-SMX. We evaluated patient demographics and clinical outcomes after CAP according to the susceptibility of index UTI to TMP-SMX. Multivariate analysis was used to identify the predictive factors for breakthrough UTI.

RESULTS

Of the 81 children, 42 were classified into the susceptible group and 39 into the resistant group. The proportion of breakthrough UTI was 31.0% (13/42) in the susceptible group and 53.8% (21/39) in the resistant group (P = 0.037). Progression of renal scarring was observed in 0% of children in the susceptible group and 15% in the resistant group (P = 0.053). Multivariate analysis showed that TMP-SMX resistance and initial renal scarring were significant predictors of breakthrough UTI.

CONCLUSION

Susceptibility of index UTI to prophylactic antibiotics is a risk factor of breakthrough UTI and is associated with poor clinical outcomes in children with primary VUR receiving CAP.

Parental Preferences for Vesicoureteral Reflux Treatment: A Crowd-sourced, Best-worst Scaling Study

OBJECTIVE

To quantitatively evaluate parental preferences for the various treatments for vesicoureteral reflux using crowd-sourced best-worst scaling, a novel technique in urologic preference estimation.

METHODS

Preference data were collected from a community sample of parents via 2 best-worst scaling survey instruments published to Amazon's Mechanical Turk online community. Attributes and attribute levels were selected following extensive review of the reflux literature. Respondents completed an object case best-worst scaling exercise to prioritize general aspects of reflux treatments and multiprofile case best-worst scaling to elicit their preferences for the specific differences in reflux treatments. Data were analyzed using multinomial logistic regression. Results from the object-case provided probability scaled values (PSV) that reflected the order of importance of attributes.

RESULTS

We analyzed data for 248 and 228 respondents for object and multiprofile case BWS, respectively. When prioritizing general aspects of reflux treatment, effectiveness (PSV = 20.37), risk of future urinary tract infection (PSV = 14.85), and complication rate (PSV = 14.55) were most important to parents. Societal cost (PSV = 1.41), length of hospitalization (PSV = 1.09), and cosmesis (PSV = 0.91) were least important. Parents perceived no difference in preference for the cosmetic outcome of open vs minimally invasive surgery (P = .791). Bundling attribute preference weights, parents in our study would choose open surgery 74.9% of the time.

CONCLUSION

High treatment effectiveness was the most important and preferred attribute to parents. Alternatively, cost and cosmesis were among the least important. Our findings serve to inform shared parent-physician decision-making for vesicoureteral reflux.

Pediatric voiding cystourethrography: An essential examination for urologists but a terrible experience for children

Voiding cystourethrography is the most important fluoroscopic examination in pediatric urology for the investigation of lower urogenital tract diseases, such as vesicoureteral reflux or urethral stricture. However, this invasive procedure imposes a significant burden on children and their parents, and recently there has been a paradigm shift in the diagnosis and treatment of vesicoureteral reflux. In the 2011 revision, the American Academy of Pediatrics guidelines on urinary tract infection recommended abandoning routine voiding cystourethrography after the first febrile urinary tract infection. In 2014, the randomized intervention for children with vesicoureteral reflux study recommended discontinuation of routine continuous antibiotic prophylaxis for vesicoureteral reflux. The time is now ripe to radically reconsider indications for voiding cystourethrography and the procedure itself.

Uropathogen Resistance and Antibiotic Prophylaxis: A Meta-analysis

CONTEXT

Limited data exist regarding uropathogen resistance in randomized controlled trials of urinary tract infection (UTI) prevention and antibiotic prophylaxis.

OBJECTIVE

To assess the effect of prophylaxis on developing a multidrug-resistant first recurrent UTI among children with vesicoureteral reflux.

DATA SOURCES

Cochrane Kidney and Transplant Specialized Register through May 25, 2017.

STUDY SELECTION

Randomized controlled trials of patients ≤18 years of age with a history of vesicoureteral reflux being treated with continuous antibiotic prophylaxis compared with no treatment or placebo with available antibiotic sensitivity profiles.

DATA EXTRACTION

Two independent observers abstracted data and assessed quality and validity per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Adjusted meta-analyses were performed by using a mixed-effects logistic regression model.

RESULTS

One thousand two hundred and ninety-nine patients contributed 224 UTIs. Patients treated with prophylaxis were more likely to have a multidrug-resistant infection (33% vs 6%, P < .001) and were more likely to receive broad-spectrum antibiotics (68% vs 49%, P = .004). Those receiving prophylaxis had 6.4 times the odds (95% confidence interval: 2.7-15.6) of developing a multidrug-resistant infection. One multidrug-resistant infection would develop for every 21 reflux patients treated with prophylaxis.

LIMITATIONS

Variables that may contribute to resistance such as medication adherence and antibiotic exposure for other illnesses could not be evaluated.

CONCLUSIONS

Prophylaxis increases the risk of multidrug resistance among recurrent infections. This has important implications in the risk-benefit assessment of prophylaxis as a management strategy and in the selection of empirical treatment of breakthrough infections in prophylaxis patients.

Antimicrobial Pharmacotherapy Management of Urinary Tract Infections in Pediatric Patients

Objective: To discuss the risk factors, microbial resistance rates, and pharmacotherapy, including antimicrobial choices and medication dosage regimens, for urinary tract infections (UTIs) in pediatric patients. Data Sources: A MEDLINE literature search (1985 to December 2017) was performed using the following keywords and associated medical subject headings: urinary tract infection, antimicrobial, treatment, and children. Study Selection and Data Extraction: Search was conducted to identify clinical trials, systematic reviews, and guidelines. Search was filtered to include studies with age range between birth and 18 years and published in English. Additional references were identified from selected review articles. Data Synthesis: In total, 27 studies investigating microbial resistance, 31 studies assessing antimicrobial efficacy, 34 studies describing prophylaxis, and 6 systematic reviews were included. The resistance patterns differed across age groups and affected the choice of empirical therapy. If pyelonephritis is suspected, empiric antimicrobials should have high urinary and sufficient parenchymal concentrations. Nitrofurantoin has low microbial resistance rates and can generally be used empirically for treating uncomplicated cystitis in children >1 month of age. Trimethoprim-sulfamethoxazole resistance has increased and should be avoided unless local susceptibility data are available. Certain patients with recurrent UTIs or renal abnormalities may require antimicrobial prophylaxis, which may be associated with adverse effects, such as intolerability or an increased risk of microbial resistance. Conclusion: The resistance pattern of uropathogens should be considered prior to initiating therapy. Controlled trials with large samples are needed to compare the treatment duration of various antimicrobial regimens and the specific role of prophylactic antimicrobials.

An update on new antibiotic prophylaxis and treatment for urinary tract infections in children

INTRODUCTION

This review focuses on the treatment of urinary tract infections (UTI) in children and in particular its recent changes. Areas covered: Acute pyelonephritis, acute cystitis and asymptomatic bacteriuria or asymptomatic infections have to be clearly distinguished. Prompt treatment is required in pyelonephritis and cystitis, but not in asymptomatic bacteriuria or infection, in order to avoid selection of more virulent strains. This concept should be considered even in immunocompromised or bedridden children. In case of pyelonephritis, there should be no delay in beginning the antibiotic treatment in order to decrease the risk of long term complication, such as renal scars. Predisposing conditions for UTI, such as voiding anomalies and urinary tract malformation should be carefully evaluated. Expert opinion: One major concern is the increasing resistance to 3^rd generation cephalosporins. Therefore overconsumption in low-risk settings should be absolutely avoided. The prevalence of infections with E. coli producing extended spectrum ß-lactamase (ESBL) is increasing and pediatricians should be aware about the specific treatment options. Any recommendation about (initial) antibiotic treatment should be regularly updated and adapted to local resistance profiles and to economic factors in different health systems.

Contemporary Management of Vesicoureteral Reflux

CONTEXT

Vesicoureteral reflux (VUR) remains the most interesting topic of pediatric urology due to the dynamic nature of recent controversial publications. Starting from the need for a diagnosis to the necessity and effectiveness of treatment in preventing scars, VUR remains in the mist. Although recent strong evidence helped as fog lights in this blurriness, more data are required for achieving crystal clearance. This article aims to summarize and discuss the current state of the evidence regarding VUR management.

OBJECTIVE

To provide a comprehensive synthesis of the main evidence in the literature on the current and contemporary management of VUR in children; to discuss conservative management with continuous antibiotic prophylaxis (CAP), especially its effectiveness and safety; and to review the current evidence regarding contemporary surgical techniques.

EVIDENCE ACQUISITION

We conducted a nonsystematic review of the literature using the recent guidelines and PubMed database regarding surveillance, CAP, endoscopic, open, laparoscopic, and robot-assisted ureteral surgical treatment.

EVIDENCE SYNTHESIS

Despite the striking results of previous studies revealing the ineffectiveness of CAP, more recent studies and their two fresh meta-analyses revealed a positive role for CAP in the contemporary management of VUR. One of the most interesting findings is the redundant rising of endoscopic correction and its final settlement to real indicated cases. Patient individualization in the contemporary management of VUR seems to be the keyword. The evidence in the literature showed a safe and effective use of laparoscopic and robot-assisted laparoscopic reimplantations.

CONCLUSIONS

The goal of VUR treatment is to prevent the occurrence of febrile urinary tract infections and formation of scars in the renal parenchyma. The approach should be risk adapted and individualized according to current knowledge. Individual risk is influenced by the presentation age, sex, history of pyelonephritis and renal damage, grade of reflux, bladder bowel dysfunction, and circumcision status.

PATIENT SUMMARY

Vesicoureteral reflux is a nonphysiological reflux of urine from the bladder through the ureters to the kidney. Treatment depends on the presentation of the vesicoureteral reflux (VUR). Therapeutic options range from watchful waiting to open surgery. This article aims to summarize and discuss the current state of the evidence regarding VUR management.

Advances in paediatric urology

Paediatric urological surgery is often required for managing congenital and acquired disorders of the genitourinary system. In this Series paper, we highlight advances in the surgical management of six paediatric urological disorders. The management of vesicoureteral reflux is evolving, with advocacy ranging from a less interventional assessment and antimicrobial prophylaxis to surgery including endoscopic injection of a bulking agent and minimally invasive ureteric reimplantation. Evidence supports early orchidopexy to improve fertility and reduce malignancy in boys with undescended testes. A variety of surgical techniques have been developed for hypospadias, with excellent outcomes for distal but not proximal hypospadias. Pelvi-ureteric junction obstruction is mostly detected prenatally; indications for surgery have been refined with evidence, and minimally invasive pyeloplasty is now standard. The outlook for patients with neurogenic bladder has been transformed by a combination of clean intermittent catheterisation, algorithms of diagnostic investigations, and innovative medical and surgical therapies. Posterior urethral valves are associated with considerable mortality; fetal diagnosis allows stratification of candidates for intervention, but ongoing bladder dysfunction in patients after valve ablation remains a cause of long-term morbidity.

Incidence of urinary tract infections in infants with antenatally diagnosed hydronephrosis-A retrospective single center study

OBJECTIVE

To evaluate the incidence of urinary tract infections (UTIs) in infants with antenatal hydronephrosis (AHN).

MATERIALS AND METHODS

A cohort of AHN patients admitted to our institution between 2003 and 2013 were identified. Altogether 192 patients with nonrefluxing hydronephrosis (HN, n=135), nonrefluxing hydroureteronephrosis (HUN, n=21), or vesicoureteral reflux (VUR, n=36) were identified. Patients with complex anomalies or neonatal decompression of the urinary tract were excluded. Information about UTIs diagnosed among the AHN patients was collected and compared with data from 58 controls.

RESULTS

During the median follow-up time of 2.6 (0.3-11.2) years, 24 (13%) patients (15 (10%) males and 9 (19%) females) and 2 (3%) controls experienced at least one UTI (p=0.033). Eighteen (69%) UTIs were febrile. The males had the first UTI at significantly younger age than the females (0.3, 0.0-1.7years vs. 1.0, 0.4-4.8years, p=0.010). UTI was detected in 15 (63%) patients with grade 4-5 VUR, in 8 (6%) patients with HN, and in one (5%) patient with HUN (p-values <0.001, 0.726 and >0.999 against the controls). None of the patients with grade≤3 VUR had UTI. Fifty-eight percent of the patients with UTI were on antimicrobial prophylaxis. In five (12%) cases UTI appeared within one week after voiding cystourethrography (VCUG).

CONCLUSIONS

Infants with AHN and grade 4-5 VUR had the highest risk of UTI. UTIs tented to be more common in females than in males; however, males experienced UTI at younger age than females. VCUG caused UTI in 2.3% in our material.

LEVEL OF EVIDENCE

III.

Vesicoureteral reflux and continuous prophylactic antibiotics

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

Antibiotic Prophylaxis for Urinary Tract Infection-Related Renal Scarring: A Systematic Review

CONTEXT

Acute pyelonephritis may result in renal scarring. Recent prospective studies have shown a small benefit of antibiotic prophylaxis in preventing symptomatic and febrile urinary tract infections (UTIs), while being underpowered to detect any influence in prevention of renal damage.

OBJECTIVES

Review of the literature and a meta-analysis to evaluate the effect of antibiotic prophylaxis on UTI-related renal scarring.

DATA SOURCES

Medline, Embase, and Cochrane Controlled Trials Register electronic databases were searched for studies published in any language and bibliographies of identified prospective randomized controlled trials (RCTs) performed and published between 1946 and August 2016.

STUDY SELECTION

Subjects 18 years of age or younger with symptomatic or febrile UTIs, enrolled in prospective RCTs of antibiotic prophylaxis where ^99mTc dimercaptosuccinic acid scans were performed at entry into the study and at late follow-up to detect new scar formation.

DATA EXTRACTION

The literature search, study characteristics, inclusion and exclusion criteria, and risk of bias assessment were independently evaluated by 2 authors.

RESULTS

Seven RCTs (1427 subjects) were included in the meta-analysis. Our results show no influence of antibiotic prophylaxis in preventing renal scarring (pooled risk ratio, 0.83; 95% confidence interval, 0.55-1.26) as did a subanalysis restricted to those subjects with vesicoureteral reflux (pooled risk ratio, 0.79; 95% confidence interval, 0.51-1.24).

LIMITATIONS

Limitations include the small number of studies, short duration of follow-up, and insufficient children with high-grade dilating reflux and/or renal dysplasia enrolled in the studies.

CONCLUSIONS

Antibiotic prophylaxis is not indicated for the prevention of renal scarring after a first or second symptomatic or febrile UTI in otherwise healthy children.

The Swedish infant high-grade reflux trial: UTI and renal damage

INTRODUCTION

High-grade vesicoureteral reflux (VUR) in children is associated with recurrent urinary tract infection (UTI) and renal damage. Breakthrough UTI despite continuous antibiotic prophylaxis (CAP) during the first years of life is a matter of concern and evokes early intervention. We investigated whether early endoscopic treatment (ET) of VUR grade 4-5 can reduce the risk of UTI recurrence and renal scarring.

MATERIALS AND METHODS

This prospective, randomized, controlled, multicentre, 1-year follow-up trial comprised 77 infants, <8 months of age with VUR grade 4-5 (Table) randomized to CAP (n = 39) or ET (with prophylaxis until resolution) (n = 38). Voiding cystourethrogram, ultrasound, renal scintigraphy, and free voiding observation were performed at study entry and after 1 year. Parenchymal defects were seen in 67 (87%) children at entry, 39 (34 boys, 5 girls) of them characterized as generalized. At follow-up, renal deterioration (new scars or progress in old damaged area) and symptomatic UTIs were reported.

RESULTS

There were 27 recurrent febrile UTIs in 6 (16%) children in the ET group and in 10 (26%) in the CAP group (p = 0.43), in eight (36%) girls and eight (15%) boys (p = 0.039). Successful VUR outcome (VUR 0-2) was seen in 22 (59%) in the ET and eight (21%) in the CAP group (p = 0.0014). Multiple recurrences were only seen in patients with persistent dilating reflux at follow-up (p = 0.019). Deterioration on scintigraphy was seen in eight children (9 kidneys) with no difference between treatment groups (p = 0.48) or sex (p = 0.17). Renal deterioration was associated with high bladder capacity (BC) and large residual volume (PVR) at 1 year (p = 0.0092 and p = 0.041). Six of the eight children with renal deterioration had a recurrent UTI (p = 0.0032). Seven of nine renal units with deterioration were seen in children with persistent VUR 3-5 at follow-up. Univariable logistic regression identified female sex and high PVR as positive predictors for recurrent UTI (p = 0.039 and 0.034) and high PVR tended to predict renal deterioration (p = 0.053).

DISCUSSION

No differences between the treatment groups regarding recurrent UTI and renal deterioration could be found. Increased PVR and female sex were positive predictors for UTI recurrences. VUR grade at follow-up was correlated to UTI recurrence and renal deterioration.

CONCLUSION

This study did not show any difference between ET and CAP in reducing the risk of UTI recurrence or renal deterioration. The rate of VUR resolution was higher in the ET group and VUR grade at follow-up correlated with both UTI recurrence and renal deterioration.

Continuous antibiotic prophylaxis in the setting of prenatal hydronephrosis and vesicoureteral reflux

Continuous antibiotic prophylaxis (CAP) has traditionally been offered for children with recurrent urinary tract infections (UTIs) or those at risk, including children diagnosed with prenatal hydronephrosis (HN) and vesicoureteral reflux (VUR). However, indications for antibiotic prophylaxis are controversial, data on who should benefit from this therapy is conflicting and, thus, guidelines are unable to provide conclusive recommendations. In the setting of prenatal HN, although randomized trials are currently underway, most evidence is derived from low- to moderate-quality observational studies. Although there is no benefit in those with low-grade HN, a systematic review of the available studies showed that high-grade HN patients on prophylaxis experienced fewer infections with an estimated number needed to treat of 7. On the other hand, there are eight randomized trials that have investigated the use of antibiotic prophylaxis in the setting of VUR. Although four of the studies have demonstrated some value of prophylaxis and the other four have not, meta-analysis has shown an overall benefit of antibiotic prophylaxis in preventing infections. The observed differences are likely due to different inclusion criteria and study heterogeneity. Although generalizing results of meta-analyses to all children is tempting, an individualized approach, by determining which patients best behave like those of the included studies, is recommended.

Off-label-use of sulfur-hexafluoride in voiding urosonography for diagnosis of vesicoureteral reflux in children: A survey on adverse events

AIM

To evaluate the risk profile of sulfur hexafluoride in voiding urosonography (VUS) based on a large cohort of children.

METHODS

Since 2011 sulfur hexafluoride (SH, SonoVue^®, Bracco, Italy) is the only ultrasound contrast available in the European Union and its use in children has not been approved. Within a 4-year-period, 531 children with suspected or proven vesicoureteral reflux (f/m = 478/53; mean age 4.9 years; 1 mo-25.2 years) following parental informed consent underwent VUS with administration of 2.6 ± 1.2 mL SH in a two-center study. A standardized telephone survey on adverse events was conducted three days later.

RESULTS

No acute adverse reactions were observed. The survey revealed subacute, mostly self-limited adverse events in 4.1% (22/531). The majority of observed adverse events (17/22) was not suspected to be caused by an allergic reaction: Five were related to catheter placement, three to reactivated urinary tract infections, five were associated with perineal disinfection before voiding urosonography or perineal dermatitis and four with a common cold. In five patients (0.9%) hints to a potential allergic cause were noted: Perineal urticaria was reported in three interviews and isolated, mild fever in two. These were minor self-limited adverse events with a subacute onset and no hospital admittance was necessary. Ninety-six point two percent of the parents would prefer future VUS examinations with use of SH.

CONCLUSION

No severe adverse events were observed and indications of self-limited minor allergic reactions related to intravesical administration of SH were reported in less than 1%.

Polymorphisms in α-Defensin-Encoding DEFA1A3 Associate with Urinary Tract Infection Risk in Children with Vesicoureteral Reflux

The contribution of genetic variation to urinary tract infection (UTI) risk in children with vesicoureteral reflux is largely unknown. The innate immune system, which includes antimicrobial peptides, such as the α-defensins, encoded by DEFA1A3, is important in preventing UTIs but has not been investigated in the vesicoureteral reflux population. We used quantitative real-time PCR to determine DEFA1A3 DNA copy numbers in 298 individuals with confirmed UTIs and vesicoureteral reflux from the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) Study and 295 controls, and we correlated copy numbers with outcomes. Outcomes studied included reflux grade, UTIs during the study on placebo or antibiotics, bowel and bladder dysfunction, and renal scarring. Overall, 29% of patients and 16% of controls had less than or equal to five copies of DEFA1A3 (odds ratio, 2.09; 95% confidence interval, 1.40 to 3.11; P<0.001). For each additional copy of DEFA1A3, the odds of recurrent UTI in patients receiving antibiotic prophylaxis decreased by 47% when adjusting for vesicoureteral reflux grade and bowel and bladder dysfunction. In patients receiving placebo, DEFA1A3 copy number did not associate with risk of recurrent UTI. Notably, we found that DEFA1A3 is expressed in renal epithelium and not restricted to myeloid-derived cells, such as neutrophils. In conclusion, low DEFA1A3 copy number associated with recurrent UTIs in subjects in the RIVUR Study randomized to prophylactic antibiotics, providing evidence that copy number polymorphisms in an antimicrobial peptide associate with UTI risk.

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.

Design and Methodological Considerations of the Centers for Disease Control and Prevention Urologic and Renal Protocol for the Newborn and Young Child with Spina Bifida

PURPOSE

Care of children with spina bifida has significantly advanced in the last half century, resulting in gains in longevity and quality of life for affected children and caregivers. Bladder dysfunction is the norm in patients with spina bifida and may result in infection, renal scarring and chronic kidney disease. However, the optimal urological management for spina bifida related bladder dysfunction is unknown.

MATERIALS AND METHODS

In 2012 the Centers for Disease Control and Prevention convened a working group composed of pediatric urologists, nephrologists, epidemiologists, methodologists, community advocates and Centers for Disease Control and Prevention personnel to develop a protocol to optimize urological care of children with spina bifida from the newborn period through age 5 years.

RESULTS

An iterative quality improvement protocol was selected. In this model participating institutions agree to prospectively treat all newborns with spina bifida using a single consensus based protocol. During the 5-year study period outcomes will be routinely assessed and the protocol adjusted as needed to optimize patient and process outcomes. Primary study outcomes include urinary tract infections, renal scarring, renal function and bladder characteristics. The protocol specifies the timing and use of testing (eg ultrasonography, urodynamics) and interventions (eg intermittent catheterization, prophylactic antibiotics, antimuscarinic medications). Starting in 2014 the Centers for Disease Control and Prevention began funding 9 study sites to implement and evaluate the protocol.

CONCLUSIONS

The Centers for Disease Control and Prevention Urologic and Renal Protocol for the Newborn and Young Child with Spina Bifida began accruing patients in 2015. Assessment in the first 5 years will focus on urinary tract infections, renal function, renal scarring and clinical process improvements.

Urinary tract infection in the setting of vesicoureteral reflux

Vesicoureteral reflux (VUR) is the most common underlying etiology responsible for febrile urinary tract infections (UTIs) or pyelonephritis in children. Along with the morbidity of pyelonephritis, long-term sequelae of recurrent renal infections include renal scarring, proteinuria, and hypertension. Treatment is directed toward the prevention of recurrent infection through use of continuous antibiotic prophylaxis during a period of observation for spontaneous resolution or by surgical correction. In children, bowel and bladder dysfunction (BBD) plays a significant role in the occurrence of UTI and the rate of VUR resolution. Effective treatment of BBD leads to higher rates of spontaneous resolution and decreased risk of UTI.

Renal Scarring in the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) Trial

BACKGROUND AND OBJECTIVES

The main objectives of the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial were to evaluate the role of antimicrobial prophylaxis in the prevention of recurrent urinary tract infection (UTI) and renal scarring in children with vesicoureteral reflux (VUR). We present a comprehensive evaluation of renal scarring outcomes in RIVUR trial participants.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This multicenter, randomized, placebo-controlled trial enrolled 607 children aged 2-71 months with grade 1-4 VUR diagnosed after a first or second febrile or symptomatic UTI. Study participants received trimethoprim-sulfamethoxazole or placebo and were followed for 2 years. Renal scarring was evaluated by baseline and follow-up (99m)technetium dimercaptosuccinic acid (DMSA) renal scans that were reviewed independently by two blinded reference radiologists.

RESULTS

At the end of the study, 58 (10%) of 599 children and 63 (5%) of 1197 renal units had renal scarring. New renal scarring did not differ between the prophylaxis and placebo groups (6% versus 7%, respectively). Children with renal scarring were significantly older (median age, 26 versus 11 months; P=0.01), had a second UTI before enrollment (odds ratio [OR], 2.85; 95% confidence interval [95% CI], 1.38 to 5.92), were more likely to be Hispanic (OR, 2.22; 95% CI, 1.13 to 4.34), and had higher grades of VUR (OR, 2.79; 95% CI, 1.56 to 5.0). The proportion of new scars in renal units with grade 4 VUR was significantly higher than in units with no VUR (OR, 24.2; 95% CI, 6.4 to 91.2).

CONCLUSIONS

Significantly more renal scarring was seen in relatively older children and in those with a second episode of febrile or symptomatic UTI before randomization. Preexisting and new renal scars occurred significantly more in renal units with grade 4 VUR than in those with low-grade or no VUR. Antimicrobial prophylaxis did not decrease the risk of renal scarring.

The role of antimicrobial prophylaxis in the management of children with vesicoureteral reflux--the RIVUR study outcomes

The role of antimicrobial prophylaxis for the prevention of recurrent urinary tract infections in children with vesicoureteral reflux that was identified following a urinary tract infection has been the source of considerable debate. Prior studies had failed to show a benefit in the prevention of recurrent infection. The National Institutes of Health funded the Randomized Intervention for Vesicoureteral Reflux (RIVUR) study to determine if there was a benefit to the use of prophylaxis. Results of the RIVUR study indicated that there was a 50% reduction in the risk of recurrent urinary tract infection in those children on the prophylaxis arm. Adverse events with the use of prophylaxis were noted to be few. Renal scarring was noted in only a small number of children at study entry and no reduction in scarring was noted between the placebo and the treated groups. The impact of the RIVUR study on the current evaluation and management of children with urinary tract infections and vesicoureteral reflux is detailed.

The RIVUR trial: a factual interpretation of our data

Vesicoureteral reflux (VUR) increases the risk of urinary tract infection (UTI) and renal scarring. Many prospective studies have evaluated the role of antimicrobial prophylaxis in the prevention of recurrent UTI and renal scarring in children with VUR. Of these, the RIVUR trial was the largest, randomized, placebo-controlled, double blind, multicenter study, involving 607 children aged 2-72 months with grade I-IV VUR and a first or second symptomatic UTI. The median age of children in the RIVUR trial was 12 months, 92% were female, 91% were randomized after a first UTI, 86% had a febrile index UTI, and 71 (56%) of 126 toilet-trained children had bladder bowel dysfunction. Trimethoprim/sulfamethoxazole reduced the risk of UTI recurrences by 50% (hazard ratio 0.50; 95% confidence interval 0.34-0.74) as compared to placebo. No significant difference was seen in renal scarring between the two groups. However, this does not invalidate the role of prophylaxis in preventing renal scars because RIVUR and other recent prospective studies were not designed to address renal scarring as a primary study endpoint. In view of the RIVUR Trial and other studies that showed similar results, albeit in selected groups of patients, the debate on antimicrobial prophylaxis should shift from "no prophylaxis" to "selective prophylaxis" in children with VUR.