Risk Factors for Febrile Urinary Tract Infection in Infants with Prenatal Hydronephrosis: Comprehensive Single Center Analysis

Fetal urinary tract dilation: What to tell the parents

Urinary tract dilation (UTD), which refers to the abnormal dilation of the urinary collection system, is the most common finding on prenatal ultrasound and presents with varying severity, presentation, etiology, and prognosis. Prenatal classification and risk stratification aim to prevent postnatal complications, such as urinary tract infections and further kidney dysfunction. Parents expecting a child with UTD should be counseled by a multidisciplinary team consisting of maternal-fetal medicine specialists, and pediatric urology and nephrology providers. This review summarizes the key points in the diagnostic evaluation and management during the prenatal and initial postnatal period, focusing on the information that should be provided to future parents. We address frequently asked parental questions and concerns that our multidisciplinary clinical practice faces.

The role of circumcision in preventing urinary tract infections in children with antenatal hydronephrosis: Systematic review and meta-analysis

INTRODUCTION

Circumcision has been reported to reduce the risk of urinary tract infections (UTIs) in boys with antenatal hydronephrosis (HN). Our aim was to compare the incidence of UTIs in circumcised vs. uncircumcised boys with antenatal HN by conducting a systematic review and meta-analysis.

STUDY DESIGN

A comprehensive search was performed until December 2022. Comparative studies were evaluated according to Cochrane collaboration recommendations. Assessed measures included: UTIs, continuous antibiotic prophylaxis (CAP) use, renal outcomes, and circumcision complications. Odds ratios (OR) and mean difference with 95% confidence interval (CI) were extrapolated from available data. Random-effects meta-analysis were performed.

RESULTS

Twenty-three studies describing 9093 boys with antenatal HN were identified, including 4677 uncircumcised and 4416 circumcised boys. Overall effect estimates demonstrate that circumcised boys have significantly reduced odds of developing any UTI [OR 0.26, 95%CI 0.21, 0.32; p < 0.001]]. In addition, there a significantly reduced odds of developing UTI when circumcised and on CAP [OR 0.19, 95% CI 0.13, 0.30; p < 0.001]. When stratifying by etiology, circumcision reduced the odds of UTI in boys with isolated HN [OR 0.33, 95% CI 0.16, 0.68; p = 0.003], vesicoureteral reflux [OR 0.23, 95% CI 0.13, 0.42; P < 0.00001], or with posterior urethral valves [OR 0.29, 95% CI 0.13, 0.64; p = 0.002].

DISCUSSION

Circumcision reduces the incidence of UTIs in boys with antenatal HN. This review is limited by the varied definitions of UTIs and inconsistent reporting on HN etiology, renal outcomes, and circumcision complications.

CONCLUSIONS

Circumcision should be considered in boys with antenatal HN to prevent the risk of developing UTI. Further research is warranted to individualize the prophylactic role of circumcision for patients with HN.

Abnormal Development of Microbiota May Be a Risk Factor for Febrile Urinary Tract Infection in Infancy

Febrile urinary tract infection (fUTI) is common in infants, but specific risk factors for developing it remain unclear. As most fUTIs are caused by ascending infections of intestinal bacteria, dysbiosis-an imbalance in gut microbial communities-may increase fUTI risk. This study was conducted to test the hypothesis that abnormal development of gut microbiota during infancy increases the risk of developing fUTI. Stool samples were collected from 28 infants aged 3-11 months with first-onset fUTI (fUTI group) and 51 healthy infants of the same age (HC group). After bacterial DNA extraction, 16S rRNA expression was measured and the diversity of gut microbiota and constituent bacteria were compared between the two groups. The alpha diversity of gut microbiota (median Shannon index and Chao index) was significantly lower in the fUTI group (3.0 and 42.5) than in the HC group (3.7 and 97.0; p < 0.001). The beta diversity also formed different clusters between the two groups (p < 0.001), suggesting differences in their microbial composition. The linear discriminant analysis effect size showed that the fUTI group proportionally featured significantly more Escherichia-Shigella in the gut microbiota (9.5%) than the HC group (3.1%; p < 0.001). In summary, abnormal gut microbiota development during infancy may increase the risk of fUTI.

Antenatally detected urinary tract dilatation: long-term outcome

This review provides updated knowledge on the long-term outcomes among children with antenatally diagnosed urinary tract dilatation (UTD), previously often referred to as antenatal hydronephrosis. Different definitions of UTD exist, which makes comparison between studies and generalized conclusions difficult. Roughly, one-third of antenatally diagnosed UTD, defined as a renal pelvis anterior posterior diameter (APD) of ≥ 4 mm in the second trimester and/or ≥ 7 mm in the third trimester, will resolve before birth, another third will resolve within the first years of life, and in the remaining cases, UTD will persist or a congenital abnormality (CAKUT) will be diagnosed postnatally. The risk of a postnatal CAKUT diagnosis increases with the degree of prenatal and postnatal dilatation, except for vesicoureteral reflux (VUR), which cannot be predicted from the degree of UTD. Urinary tract infections (UTIs) occur in 7-14% of children with UTD during the first years of life. The risk of UTI is higher in children with traditional risk factors for UTI, such as dilated VUR, hydroureteronephrosis, female gender, and intact foreskin. Continuous antibiotic prophylaxis may be considered in selected patients during the first years of life. In long-term follow-ups, permanent kidney damage is diagnosed in approximately 40% of children with moderate or severe UTD, but hypertension, proteinuria, and/or reduced eGFR are uncommon (0-5%). In children with mild UTD, the long-term outcome is excellent, and these children should not be subjected to unnecessary examinations and/or follow-up.

Circumcision reduces urinary tract infection in children with antenatal hydronephrosis: Systematic review and meta-analysis

INTRODUCTION

Urinary tract infection (UTI) is more prevalent in boys with antenatal hydronephrosis (ANH). Circumcision is known to lessen the risk of UTI. This study was performed to examine the associations between circumcision and UTI among patients with ANH.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards were followed for conducting this systematic review and meta-analysis. PubMed, ScienceDirect, EMBASE, and Cochrane Library databases were searched through August 4th, 2022 to identify eligible studies. The risk of bias was measured using the Newcastle-Ottawa Scale (NOS). Review manager 5.4 was used for all analysis.

RESULTS

A total of 21 studies involving 8,968 patients with ANH were included in the meta-analysis. The incidences of UTI were 18.1% in the uncircumcised group and 4.9% in the circumcised group. From analysis, circumcision had significant protective effect against UTI with pooled OR of 0.28 (95% CI 0.23-0.32). The significant protective effects were also found in subgroup analysis of hydronephrosis etiology, including vesicoureteral reflux (pooled OR of 0.24; 95% CI 0.17-0.32), obstructive hydronephrosis (pooled OR of 0.34; 95% CI 0.21-0.53), and posterior urethral valve (pooled OR of 0.28; 95% CI 0.16-0.52).

CONCLUSION

Our meta-analysis showed that circumcision was associated with a decreased incidence of UTI in children with ANH. This benefit was consistent irrespective of the underlying cause of hydronephrosis.

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.

Role of Antibiotic Prophylaxis in the Management of Antenatal Hydronephrosis, Vesicoureteral Reflux, and Ureterocele in Infants

Widespread prenatal screening has resulted in increased detection of anomalies of the kidneys and urinary tract. Antenatal hydronephrosis (AHN) and vesicoureteral reflux (VUR) are among the most common congenital anomalies diagnosed in utero or after birth. Pediatric urologists frequently rely on continuous antibiotic prophylaxis (CAP) for managing AHN, VUR, and ureterocele, unless definitive treatment is performed. The main aim of antibiotic prophylaxis (ABP) is to prevent urinary tract infection and long-term complications. Nevertheless, the efficacy of ABP has been a source of considerable debate, and pediatricians have varied opinions on who would benefit from ABP. In this review article, we searched the currently available literature, for evidence of the role of ABP in the setting of AHN, VUR, and ureterocele. Most of our studies showed a limited benefit of ABP for HN and VUR. The data on the use of CAP in the management of ureterocele is scarce. However, due to the involvement of independent risk factors and other variables, a conclusion cannot be drawn from these studies alone. Pediatric urologists are urged to conduct randomized controlled trials to compare patients followed up with and without ABP. Given the lack of guidelines, an individualized approach should be used for the use of ABP, until precise guidelines and recommendations are developed.

Postnatal outcomes of babies diagnosed with hydronephrosis in utero in a tertiary care centre in India over half a decade

Background

Prenatal hydronephrosis is defined as the dilatation of the fetal renal pelvis and/or calyces and is the commonest anomaly detected in utero

Methods

This was a retrospective study to look at how well 148 antenatally detected cases of fetal hydronephrosis correlated with postnatal evaluation.

Results

Antenatal hydronephrosis was detected with a prevalence of 0.33%. The mean gestational age at diagnosis was 25.48 [standard deviation (SD) 6.36]. One hundred and sixteen (78.3%) fetuses had serial ultrasound scans during pregnancy to look for the progression of the condition. At the time of diagnosis, 30.1% of the fetuses were diagnosed to have mild hydronephrosis, 43.9% to have moderate hydronephrosis and 25.8% to have severe hydronephrosis. Follow-up ultrasounds during the prenatal period, 65% showed progression of the renal pelvis dilatation, 25.8% showed stable disease and 9.1% showed resolution on their subsequent scan. Almost half (46%) were found to have transient/physiological hydronephrosis. Thirty-one (20.9%) of the babies required an operation. An anteroposterior renal pelvis diameter (APD) of the fetal renal pelvis ≥17.5 mm can predict the need for surgery with a sensitivity of 70% and a specificity of 76.6%.

Conclusion

Counselling and decisions must be based on a series of ultrasound scans rather than a single evaluation. We use a cut-off of 17.5 mm as an indicator of possible postnatal surgical intervention.

Urology Mythbusters: should hydronephrosis grade be used to decide which newborns should undergo voiding cystourethrogram?

In this episode of Mythbusters the premise that among infants with prenatally identified urinary tract dilation (UTD), voiding cystourethrogram (VCUG) should be performed in those with higher grade UTD but not in those with lower grade UTD is critically examined. It is concluded that severity of dilation is not strongly associated with risk of vesicoureteral reflux or other anomalies diagnosed by VCUG. Therefore, using hydronephrosis grade to decide which infants with UTD should undergo VCUG is not evidence based.

A practice pattern assessment of members of the Society of Pediatric Urology for evaluation and treatment of urinary tract dilation

INTRODUCTION

Over the last decade the literature, including a multidisciplinary consensus statement, has supported a paradigm shift in management of urinary tract dilation, yet the impact on practice patterns has not been well documented.

OBJECTIVE

This study aims to elucidate specific practice patterns for treatment of prenatal unilateral urinary tract dilation and to assess surgical intervention patterns for ureteropelvic junction obstruction.

STUDY DESIGN

An online survey was distributed to 234 pediatric urologists through the Society of Pediatric Urology. The survey was composed of five clinical case scenarios addressing evaluation and management of unilateral urinary tract dilation.

RESULTS

The response rate was 71% (n = 168). Circumcision status, gender, and grade were significant factors in recommending prophylactic antibiotics for newborn urinary tract dilation. Prophylactic antibiotic use in the uncircumcised male and female was twice that of a circumcised male for grade 3 (Table). This difference was minimized for grade 4. Use of VCUG was high for circumcised males with grade 3 or 4 (Table). The choice of minimally invasive surgery for ureteropelvic junction repair increased with age from 19% for a 5-month-old, 49% for a 2-year-old, and 85% for a 10-year-old. Notably, 44% of respondents would observe a 10-year-old with intermittent obstruction. Retrograde pyelography was recommended in conjunction with repair in 65% of respondents. Antegrade stent placement was the most common choice (38-47%) for urinary diversion after pyeloplasty. Regarding postoperative imaging, only 5% opted for routine renal scan whereas most would perform renal ultrasound alone.

DISCUSSION

Practice patterns seen for use of prophylactic antibiotics are in agreement with the literature, which promotes selective use in those at highest risk for urinary tract infections. Interestingly, use of aggressive screening was not concordant with this literature. Several studies have indicated an increased usage of robotic pyeloplasty; however, results indicate that minimally invasive surgery is not preferred in those younger than 6 months. Study limitations include use of clinical case scenarios as opposed to actual clinical practice.

CONCLUSION

Practice patterns for prophylactic antibiotic use for neonatal urinary tract dilation are dependent on gender, circumcision status, and grade. The use of minimally invasive surgery for ureteropelvic junction repair increased with patient age, with 50% preferring this modality at 2 years.

Time to resolution: A prospective evaluation from the Society for Fetal Urology hydronephrosis registry

INTRODUCTION

The resolution rate of prenatal urinary tract dilation (UTD) has been documented in several retrospective studies. The present study analyzed prospective observational registry data, with the aim of determining time to resolution among patients prenatally identified with mild postnatal UTD.

MATERIALS AND METHODS

A total of 248 subjects, from four centers, were prospectively enrolled from 2008 to 2015. Exclusion criteria included other anomalies (n = 69), fewer than two ultrasounds, and/or <3 months follow-up (n = 26). Resolution was defined as Outcome A (SFU 0) and Outcome B (SFU 0/1). Fisher's exact test, Mann-Whitney U or Kruskal-Wallis test and Kaplan-Meier were used for analysis.

RESULTS/DISCUSSION

The median follow-up for 179 (n = 137 males) subjects was 15 months (IQR 7-24), range 0-56 months. VCUG was performed in 100 (57%) and VUR identified in 15 (15%). There was no association with reflux and resolution (P = 0.72). For resolution assessment (n = 153), lower grades were likely to resolve and demonstrated a higher rate in the Outcome B classification. Time to resolution also favored lower grades, with the majority resolving within 2 years (Figure). Surgical intervention was performed in 14 (8%). It is interesting to note that regardless of grade of UTD, there was no difference in frequency of US or the time that RUS was first performed. Practitioners performed the first RUS of life within a narrow window ranging from 0.27 RUS/month for Grade 1 UTD to 0.30 RUS/month for Grade 4 UTD. It was speculated that this practice pattern occurrence likely reflected the deficiency in knowledge by primary care providers, and identified a potential opportunity for education. The SFU registry substantiates that the vast majority of patients will demonstrate transient UTD and most cases that do not resolve will improve within 2 years of life. This data could be used to further an evidenced-based approach towards the evaluation and management of prenatal UTD, as outlined in the multidisciplinary consensus statement for prenatal urinary tract dilation.

CONCLUSIONS

This prospective registry confirms that the majority of prenatal UTD is transient, resolution occurs within the first 3 years of life, and most patients will not need intervention. Redefining SFU 1 as normal increased the resolution rate. A large proportion of patients were not evaluated with a VCUG, therefore impact of VUR could not be determined.

Role of antibiotic prophylaxis in antenatal hydronephrosis: A systematic review from the European Association of Urology/European Society for Paediatric Urology Guidelines Panel

BACKGROUND

The benefits and harms of continuous antibiotic prophylaxis (CAP) versus observation in patients with antenatal hydronephrosis (ANH) are controversial.

OBJECTIVE

The aim was to determine the effectiveness of CAP for ANH, and if beneficial to determine the best type and regimen of antibiotic and the most harmful to provide guidance for clinical practice.

METHODS

A systematic literature search was performed in databases including Medline, Embase, and Cochrane in June 2015. The protocol was prospectively registered to PROSPERO (CRD42015024775). The search started from 1980, when maternal ultrasound was first introduced into clinical practice. Eligible studies were critically evaluated for risk of bias using Revman software. The outcomes included reduction in urinary tract infections (UTI), drug-related adverse events and kidney functions.

RESULTS

Of 797 articles identified, 57 full text articles and six abstracts were eligible for inclusion (2 randomized controlled trials, 11 non-randomized comparative studies, and 50 case series). It remains unclear whether CAP is superior to observation in decreasing UTIs. No conclusion could be drawn for drug-related adverse events and kidney function because of lack of data. Children who were not circumcised, with ureteral dilatation, and high-grade hydronephrosis may be more likely to develop UTI, and CAP may be warranted for these subgroups of patients. A majority of the studies had low-to-moderate quality of evidence and with high risk of bias.

CONCLUSIONS

The benefits of CAP in a heterogeneous group of children with ANH involving different etiologies remains unproven. However, the evidence in the form of prospective and retrospective observational studies has shown that it reduces febrile UTI in particular subgroups.

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.

Antibiotic prophylaxis for prevention of urinary tract infections in prenatal hydronephrosis: An updated systematic review

INTRODUCTION

While continuous antibiotic prophylaxis (CAP) is currently recommended to prevent urinary tract infections (UTIs) in infants with prenatal hydronephrosis (HN), this recommendation is not evidence-based. The objective of this study was to systematically determine whether CAP reduces UTIs in the HN population.

METHODS

Applicable trials were identified through an electronic search of MEDLINE (1946-2015), EMBASE (1980-2016), CINAHL (1982-2016), and CENTRAL (1993-2016) and through a hand search of American Urological Association (AUA) (2012-2015) and European Society for Pediatric Urology (ESPU) (2012-2015) abstracts, as well as reference lists of included trials. The search strategy was not limited by language or year of publication. Eligible studies compared CAP to no CAP in patients with antenatal HN, <2 years of age, and reported development of UTI and HN grades. Two independent reviewers performed title and abstract screening, full-text review, and quality appraisal.

RESULTS

Of 1518 citations screened, 11 were included, contributing 3909 patients for final analysis. Of these, four (36%) were considered high-quality when assessed by the Newcastle Ottawa Scale. Meta-analysis of the non-randomized trials (n=10) provided similar pooled UTI rates, regardless of CAP use: 9.9% (95% confidence interval [CI] 8.4-11.4%) for CAP and 7.5% (95% CI 6.4-8.6%) for no CAP.

CONCLUSIONS

This systematic review and meta-analysis suggests there may be value in providing CAP to infants with high-grade HN; however, due to the very low-quality data from non-randomized studies, important clinical variables, such as circumcision status, were unable to be assessed.

Urinary tract infections in children with prenatal hydronephrosis: A risk assessment from the Society for Fetal Urology Hydronephrosis Registry

INTRODUCTION

Risk factors for urinary tract infection (UTI) in children with prenatal hydronephrosis (PNH) are not clearly defined. Our study aim was to describe incidence and identify factors associated with UTI among a cohort of children diagnosed with PNH.

MATERIAL AND METHODS

Patients with confirmed PNH from four medical centers were prospectively enrolled in the Society for Fetal Urology (SFU) hydronephrosis registry between 9/2008 and 10/2015. Exclusion criteria included enrollment because of UTI, associated congenital anomalies, and less than 1-month follow-up. Univariate analysis was performed using Fisher's Exact test or Mann-Whitney U. Probability for UTI was determined by Kaplan-Meier curve.

RESULTS

Median follow-up was 12 (IQR 4-20) months in 213 patients prenatally diagnosed with hydronephrosis. The majority of the cohort was male (72%), Caucasian (77%), and 26% had high grade (SFU 3 or 4) hydronephrosis. Circumcision was performed in 116/147 (79%) with known status, 19% had vesicoureteral reflux (VUR), and 11% had ureteral dilatation. UTI developed in 8% (n = 18), 89% during their first year of life. Univariate analysis found UTI developed more frequently in females (p < 0.001), uncircumcised males (p < 0.01), and the presence of parenchymal renal cyst (p < 0.05). Logistic regression found renal cyst to no longer be significant, but female gender a significant risk factor for development of UTI (p < 0.001). Regression analysis stratified by gender found neither hydronephrosis grade nor parenchymal renal cyst to be significant risk factors for UTI development among females. However, hydronephrosis grade and circumcision status were significant risk factors for development of UTI among males (p < 0.05 and p < 0.01, respectively).

CONCLUSION

Identification of factors associated with UTI in patients with PNH is still progressing; however, several observational studies have identified groups that may be at increased risk of UTI. Use of prophylactic antibiotics (PA), degree of kidney dilation, gender, and circumcision status all have been reported to have some degree of impact on UTI. A previous study identified risk factors for UTI as female gender, uncircumcised status, hydroureteronephrosis, and VUR, and reported that prophylaxis provided a protective effect on prevention of UTI. Our data mirror those in some respect, identifying an association of UTI with female gender and, among males, uncircumcised status, and high grade hydronephrosis. However, we were unable to demonstrate an association between UTI and the use of PA, presence of VUR, dilated ureter, or renal duplication in this observational registry.

From Research Question to Conducting a Randomized Controlled Trial on Continuous Antibiotic Prophylaxis in Prenatal Hydronephrosis: A Rational Stepwise Process

INTRODUCTION AND OBJECTIVES

Continuous antibiotic prophylaxis (CAP) use to prevent urinary tract infections (UTI) in infants with prenatal hydronephrosis (HN) remains controversial. Lack of consensus guidelines and diverse practice patterns for postnatal management of HN highlight the dire need for higher level of evidence studies. Herein, we aim to describe the steps from developing a well-defined research question to execute a multicentered randomized controlled trial (RCT) to address the issue of CAP use in patients with prenatal HN.

MATERIALS AND METHODS

The steps involved were (1) choosing the proper research question, (2) survey of practice patterns and establishing clinical equipoise, (3) systematic review of the literature, (4) reviewing own practice, (5) longitudinal prospective study, (6) pilot study, (7) cost-utility analysis, and (8) definitive RCT (clinical trials registry number: NCT01140516). An update of our previous systematic review was conducted using two electronic databases and gray literature from 2010 to 2015. Eligibility criteria included studies of children <2 years old with postnatally confirmed prenatal HN, receiving CAP or not, and reporting on development of UTIs, capturing information on voiding cystourethrogram result and HN grade. Full-text screening was conducted by two independent reviewers. UTI rates in patients with high-grade HN were compared across different study designs. Finally, blinded comparative analysis of UTI rates between placebo and treatment groups was carried out using chi-square test.

RESULTS

UTI rates in patients with high-grade HN by their respective study design were: 25% for systematic review, 20% for retrospective study, 21% for prospective and pilot studies, and 13% for the definitive RCT thus far. Regardless of the type of study design, patients with hydroureteronephrosis had significantly higher (threefold to sixfold) UTI rates than those with isolated HN. Our updated systematic review yielded 486 citations, of which 9 (n = 1987 infants) observational studies met eligibility criteria.

CONCLUSION

UTI rates in patients with high-grade HN dropped from 25% in observational studies to 13% in our RCT. This decline in UTI rate demonstrates that study designs lacking strategies to minimize bias are more prone to overestimate treatment effects. These findings highlight the importance of conducting methodologically sound RCTs to answer clinically meaningful questions, such as the one presented here.

It is not "Just Circumcision"

OBJECTIVE

Circumcision is one of the most commonly performed operations during childhood. The procedure is often underestimated in areas where it is frequently executed due to social and religion-based indications. In fact it might be an opportunity to detect and to correct any existing penile anomaly. The aim of the study was to retrospectively evaluate the boys who were admitted to a hospital for circumcision and the outcome of the procedure.

METHODS

The boys who were brought to outpatient clinics for circumcision between 2009-2015, were retrospectively evaluated. The indications for hospital admission and the presence of associated penile anomalies were searched. All the boys were examined and operated by a single surgeon of the institution.

RESULTS

Nine hundred forty four boys were brought to pediatric surgery outpatient clinics in order to be circumcised. The operation was performed in 318 of them. The physical examination revealed penile anomalies in 29 of the 318 cases. The detected anomalies were webbed penis, penile torsion, hypospadias, chordee without hypospadias and meatal stenosis.

CONCLUSIONS

The proper examination of the boys by a physician prior to circumcision provides the detection of penile anomalies which can be corrected at the same session. The arrangements for performing circumcision in hospitals by the medical staff should be favored. The misleading perception of underestimation of the procedure where it is ritually performed, should be corrected.

Economic analysis of continuous antibiotic prophylaxis for prevention of urinary tract infections in infants with high-grade hydronephrosis

BACKGROUND

For infants with hydronephrosis, continuous antibiotic prophylaxis (CAP) may reduce urinary tract infections (UTIs); however, its value remains controversial. Recent studies have suggested that neonates with severe obstructive hydronephrosis are at an increased risk of UTIs, and support the use of CAP. Other studies have demonstrated the negligible risk for UTIs in the setting of suspected ureteropelvic junction obstruction and have highlighted the limited role of CAP in hydronephrosis. Furthermore, economic studies in this patient population have been sparse.

OBJECTIVE

This study aimed to evaluate whether the use of CAP is an efficient expenditure for preventing UTIs in children with high-grade hydronephrosis within the first 2 years of life.

STUDY DESIGN

A decision model was used to estimate expected costs, clinical outcomes and quality-adjusted life years (QALYs) of CAP versus no CAP (Fig. 1). Cost data were collected from provincial databases and converted to 2013 Canadian dollars (CAD). Estimates of risks and health utility values were extracted from published literature. The analysis was performed over a time horizon of 2 years. One-way and probabilistic sensitivity analyses were carried out to assess uncertainty and robustness.

RESULTS

Overall, CAP use was less costly and provided a minimal increase in health utility when compared to no CAP (Table). The mean cost over two years for CAP and no CAP was CAD$1571.19 and CAD$1956.44, respectively. The use of CAP reduced outpatient-managed UTIs by 0.21 infections and UTIs requiring hospitalization by 0.04 infections over 2 years. Cost-utility analysis revealed an increase of 0.0001 QALYs/year when using CAP. The CAP arm exhibited strong dominance over no CAP in all sensitivity analyses and across all willingness-to-pay thresholds.

DISCUSSION

The use of CAP exhibited strong dominance in the economic evaluation, despite a small gain of 0.0001 QALYs/year. Whether this slight gain is clinically significant remains to be determined. However, small QALY gains have been reported in other pediatric economic evaluations. Strengths of this study included the use of data from a recent systematic review and meta-analysis, in addition to a comprehensive probabilistic sensitivity analysis. Limitations of this study included the use of estimates for UTI probabilities in the second year of life and health utility values, given that they were lacking in the literature. Spontaneous resolution of hydronephrosis and surgical management were also not implemented in this model.

CONCLUSION

To prevent UTIs within the first 2 years of life in infants with high-grade hydronephrosis, this probabilistic model has shown that CAP use is a prudent expenditure of healthcare resources when compared to no CAP.

Conservative management of primary non-refluxing megaureter during the first year of life: A longitudinal observational study

INTRODUCTION

There is a lack of prospective studies that include a selected population of patients with primary non-refluxing megaureter (PM). Thus, a longitudinal observational study was designed to follow from birth a selected population of children with PM; all were antenatally diagnosed. In this paper, the outcomes observed in the first year of life are presented.

OBJECTIVE

The primary aim was to follow the natural history of PM. The secondary aim was to monitor the onset of any potential complications such as urinary tract infections (UTIs), need for hospitalization and need for surgical correction.

STUDY DESIGN

All children with antenatally diagnosed PM, born between January 2007 and December 2013, were prospectively followed with observational management: renal ultrasonography and clinical evaluation on a 3-month basis; urinalysis and culture in case of symptoms; and mercaptoacetyltriglycine (MAG3) nuclear scan once older than 1 month. Children presenting at birth with mild urinary tract dilatation were included in Group A; those with moderate-to-severe dilatation were included in Group B. Continuous antibiotic prophylaxis (CAP) was administered to Group B.

RESULTS

Forty-seven children (44 males, three females) with 58 PM were included in the study. The participants and their corresponding outcomes are shown in the summary Table. The presence of obstruction at renogram was a significant predictor of UTIs and hospitalization.

DISCUSSION

The strengths of this study were its prospective nature and its very consistent population. A limitation was the lack of control groups. The results regarding the negligible incidence of complications in Group A and the residual incidence of febrile UTIs (20%) and hospitalization (17%) in Group B, even with CAP, are in line with previous literature. In contrast, there was a higher risk of UTIs observed in children aged older than 6 months.

CONCLUSIONS

Resolution or improvement is expected in all cases of PM with mild postnatal dilatation, and close to 60% of those with moderate or severe dilatation. Surgery is rarely performed on children younger than 1 year of age. It is safe to observe children with mild urinary tract dilatation without CAP, because the incidence of UTIs is negligible. In those presenting with moderate or severe urinary tract dilatation, despite CAP, a residual incidence of UTIs is seen, and symptomatic patients often require hospitalization. However, UTIs are well tolerated and do not seem to modify outcome. Cases showing obstruction on the MAG3 scan seem to be at higher risk of UTIs and hospitalization.

Risk factors for febrile urinary tract infection in children with prenatal hydronephrosis: a prospective study

PURPOSE

We prospectively investigated the impact of risk factors for febrile urinary tract infection in infants with postnatally confirmed prenatal hydronephrosis.

MATERIALS AND METHODS

Patients seen for prenatal hydronephrosis from 2010 to 2013 were prospectively followed. Those with ectopic ureters and ureteroceles, posterior urethral valves and neuropathic bladders were excluded. The primary outcome was febrile catheter specimen urinary tract infection. We performed univariate analysis of 7 a priori risk factors, including age, hydronephrosis grade (low-I or II vs high-III or IV), type (isolated hydronephrosis vs hydroureteronephrosis), continuous antibiotic prophylaxis, vesicoureteral reflux grade, gender and circumcision status. Time to febrile urinary tract infection curves analyzed by Cox proportional regression were generated to adjust for confounders.

RESULTS

We collected data on 334 patients, of whom 78% were male. A febrile urinary tract infection developed in 65 patients (19%) at a median of 4 months (range 1 to 31). High grade hydronephrosis was present in 192 infants (57%). Continuous antibiotic prophylaxis was prescribed in 96 cases (29%). Of patients on continuous antibiotic prophylaxis 69% had high grade hydronephrosis. Vesicoureteral reflux was identified in 57 of 238 patients in whom voiding cystourethrogram was done. Reflux was grade I to III in 14 cases and grade IV or V in 43. Two-thirds of the patients with reflux were on continuous antibiotic prophylaxis. Circumcision was performed in 95 males (36%). Cox proportional regression identified female gender (HR 3.3, p = 0.02), uncircumcised males (HR 3.2, p = 0.02), hydroureteronephrosis (HR 10.9, p <0.01), vesicoureteral reflux (HR 20.8, p <0.01) and lack of continuous antibiotic prophylaxis (HR 5.2, p <0.01) as risk factors for febrile urinary tract infection. Subgroup analysis excluding vesicoureteral reflux showed that high grade prenatal hydronephrosis was also a significant risk factor (HR 3.0, p = 0.04).

CONCLUSIONS

After patients with vesicoureteral reflux were excluded from the study, females and uncircumcised males with high grade hydroureteronephrosis had significantly higher febrile urinary tract infection rates. Therefore, those patients may benefit from continuous antibiotic prophylaxis.

Pilot randomized, placebo controlled trial to investigate the effect of antibiotic prophylaxis on the rate of urinary tract infection in infants with prenatal hydronephrosis

PURPOSE

We determined the feasibility of a clinical trial of continuous antibiotic prophylaxis to prevent urinary tract infections in children with prenatal hydronephrosis.

MATERIALS AND METHODS

We piloted a blinded, randomized, placebo controlled study of the urinary tract infection rate in infants with grades III-IV prenatal hydronephrosis at our institution between August 2010 and June 2013. Study exclusion criteria were grades I/II prenatal hydronephrosis, vesicoureteral reflux, duplication anomalies and age at randomization greater than 5 months. Prospectively collected feasibility data were obtained on eligibility, enrollment status, adherence to followup schedule, and medication and protocol compliance.

RESULTS

Of 301 screened patients 220 (73.1%) were ineligible for analysis and 2 (1%) missed the randomization window. Of the remaining 81 (26.9%) eligible patients 46 were enrolled (56.8%), 29 refused (39.5%) and consent is pending in 1 (1.2%). Reasons for declining participation included parental preference for or against continuous antibiotic prophylaxis and a lack of interest in participating in clinical research. Of 46 enrolled patients 29 (63%) completed the trial, 12 (26.1%) are still in followup and 5 (10.9%) withdrew. Of the 314 medication logs dispensed 263 were returned for a 95% mean medication compliance rate.

CONCLUSIONS

Based on the results of our pilot study a realistic recruitment rate for this group of patients is established, making a definitive trial of this topic feasible. However, due to the low number of eligible patients multicenter collaboration is critical to address the effect of continuous antibiotic prophylaxis on the urinary tract infection rate in this population. After study enrollment high medication and followup compliance can be expected.