Association of Renal Scarring With Number of Febrile Urinary Tract Infections in Children

Genetic determinants of renal scarring in children with febrile UTI

BACKGROUND

Febrile urinary tract infections (UTIs) are among the most severe bacterial infections in infants, in which a subset of patients develops complications. Identifying infants at risk of recurrent infections or kidney damage based on clinical signs is challenging. Previous observations suggest that genetic factors influence UTI outcomes and could serve as predictors of disease severity. In this study, we conducted a nationwide survey of infant genotypes to develop a strategy for infection management based on individual genetic risk. Our aims were to identify genetic susceptibility variants for renal scarring (RS) and genetic host factors predisposing to dilating vesicoureteral reflux (VUR) and recurrent UTIs.

METHODS

To assess genetic susceptibility, we collected and analyzed DNA from blood using exome genotyping. Disease-associated genetic variants were identified through bioinformatics analysis, including allelic frequency tests and odds ratio calculations. Kidney involvement was defined using dimercaptosuccinic acid (DMSA) scintigraphy.

RESULTS

In this investigation, a cohort comprising 1087 infants presenting with their first episode of febrile UTI was included. Among this cohort, a subset of 137 infants who underwent DMSA scanning was subjected to gene association analysis. Remarkable genetic distinctions were observed between patients with RS and those exhibiting resolved kidney involvement. Notably, the genetic signature indicative of renal scarring prominently featured mitochondrial genes.

CONCLUSIONS

In this nationwide study of genetic susceptibility to RS after febrile UTIs in infancy, we identified a profile dominated by mitochondrial polymorphisms. This profile can serve as a predictor of future complications, including RS and recurrent UTIs.

Evidence-based clinical practice guideline for management of urinary tract infection and primary vesicoureteric reflux

We present updated, evidence-based clinical practice guidelines from the Indian Society of Pediatric Nephrology (ISPN) for the management of urinary tract infection (UTI) and primary vesicoureteric reflux (VUR) in children. These guidelines conform to international standards; Institute of Medicine and AGREE checklists were used to ensure transparency, rigor, and thoroughness in the guideline development. In view of the robust methodology, these guidelines are applicable globally for the management of UTI and VUR. Seventeen recommendations and 18 clinical practice points have been formulated. Some of the key recommendations and practice points are as follows. Urine culture with > 104 colony forming units/mL is considered significant for the diagnosis of UTI in an infant if the clinical suspicion is strong. Urine leukocyte esterase and nitrite can be used as an alternative screening test to urine microscopy in a child with suspected UTI. Acute pyelonephritis can be treated with oral antibiotics in a non-toxic infant for 7-10 days. An acute-phase DMSA scan is not recommended in the evaluation of UTI. Micturating cystourethrography (MCU) is indicated in children with recurrent UTI, abnormal kidney ultrasound, and in patients below 2 years of age with non-E. coli UTI. Dimercaptosuccinic acid scan (DMSA scan) is indicated only in children with recurrent UTI and high-grade (3-5) VUR. Antibiotic prophylaxis is not indicated in children with a normal urinary tract after UTI. Prophylaxis is recommended to prevent UTI in children with bladder bowel dysfunction (BBD) and those with high-grade VUR. In children with VUR, prophylaxis should be stopped if the child is toilet trained, free of BBD, and has not had a UTI in the last 1 year. Surgical intervention in high-grade VUR can be considered for parental preference over antibiotic prophylaxis or in children developing recurrent breakthrough febrile UTIs on antibiotic prophylaxis.

Risk factors for new renal scarring in children with vesicoureteral reflux receiving continuous antibiotic prophylaxis

To investigate the risk factors for new renal scarring (NRS) in children with vesicoureteral reflux (VUR) receiving continuous antibiotic prophylaxis (CAP). This was a single-center cohort study. The clinical data of 140 children with grade I-V VUR receiving CAP were analyzed. In this study, exposure variables were sex, younger age at the initial diagnosis of UTI ≤ 12 months, the occurrence of breakthrough urinary tract infection (BT-UTI), high-grade VUR, bilateral VUR, etiology, presence of renal scarring at the initial diagnosis and ultrasound abnormalities. The outcome was NRS. A total of 140 children were included in the risk factor analysis of NRS, 73 of whom experienced NRS, an incidence rate of 52.14%. Multivariate Cox regression suggested that the presence of renal function impairment after the initial diagnosis of UTI (OR 3.411, 95% CI 1.5751-6.646) and the occurrence of BT-UTI while receiving CAP (OR 1.995, 95% CI 1.089-2.958) were independent risk factors for NRS. Multivariate Cox regression showed that high-grade VUR had no significant effects on NRS (OR 0.940, 95% CI 0.462-1.912, P = 0.864). No significant difference was identified in multivariate Cox regression analysis in the IV-V group (vs I-III group) (OR 0.960, 95% CI 0.565-1.633, P = 0.960). Renal function impairment after the initial diagnosis of UTI and the occurrence of BT-UTI while receiving CAP were independent risk factors for NRS. Neither univariate analysis nor multivariate analysis found a correlation between VUR grade and NRS.

High-grade Vesicoureteral Reflux in Patients With Anorectal Malformation From the ARM-Net Registry: Is Our Screening Sufficient?

BACKGROUND

Vesico-ureteral reflux (VUR) is a common associated urological anomaly in anorectal malformation (ARM)-patients. High-grade VUR requires antibiotic prophylaxis to prevent urinary tract infections (UTI's), renal scarring and -failure. The exact prevalence of high-grade VUR in ARM patients is unknown. Hence, the aim of this study was determining the incidence of high-grade VUR in ARM-patients, and its associated risk factors.

METHODS

A multicenter retrospective cohort study was performed using the ARM-Net registry, including data from 34 centers. Patient characteristics, screening for and presence of renal anomalies and VUR, sacral and spinal anomalies, and sacral ratio were registered. Phenotypes of ARM were grouped according to their complexity in complex and less complex. Multivariable analyses were performed to detect independent risk factors for high-grade (grade III-V) VUR.

RESULTS

This study included 2502 patients (50 % female). Renal screening was performed in 2250 patients (90 %), of whom 648 (29 %) had a renal anomaly documented. VUR-screening was performed in 789 patients (32 %), establishing high-grade VUR in 150 (19 %). In patients with a normal renal screening, high-grade VUR was still present in 10 % of patients. Independent risk factors for presence of high-grade VUR were a complex ARM (OR 2.6, 95 %CI 1.6-4.3), and any renal anomaly (OR 3.3, 95 %CI 2.1-5.3).

CONCLUSIONS

Although renal screening is performed in the vast majority of patients, only 32 % underwent VUR-screening. Complex ARM and any renal anomaly were independent risk factors for high-grade VUR. Remarkably, 10 % had high-grade VUR despite normal renal screening. Therefore, VUR-screening seems indicated in all ARM patients regardless of renal screening results, to prevent sequelae such as UTI's, renal scarring and ultimately renal failure.

TYPE OF STUDY

Observational Cohort-Study.

LEVEL OF EVIDENCE

III.

Urologic practice patterns of pediatricians: a survey from a large multisite pediatric care center

Objective

To evaluate the practice patterns of pediatricians as they relate to common urologic concerns.

Materials and methods

An anonymous 15-question survey was created and distributed to all pediatricians at our institution, a large multisite care center. This study was deemed exempt by the institutional review board.

Results

55 of the 122 (45%) providers queried responded. 93% of the participants were female, and 7.3% were male. 55% recommended testicular self-examination at adolescence, while 39% did not recommend at any age. 78% stated that they were "Fairly confident" in the exam for undescended testicle (UTD). One-third referred patients with UDT to a subspecialist upon recognition at birth, 13% at 3 months of age, and 28% at 6 months of age. 10% reported obtaining a VCUG after the first febrile urinary tract infection (UTI), 26% after the second, and 36% only if there were abnormal findings on renal ultrasound. 28% of providers reported that they refer to pediatric urology after the initial febrile UTI. 19% provided antibiotics for UTI symptoms alone with negative urinalysis and urine culture.

Conclusions

Despite established guidelines, practice patterns varied among pediatricians. Pediatricians typically followed the AAP's guidelines regarding VCUGs (62%), with only a few adhering to urologic recommendations (9%). Despite the consistency between AAP and AUA guidelines regarding the age at which to refer a patient for cryptorchidism, about 70% of practitioners referred patients too early or too late. Harmonized, consolidated guidelines between pediatricians and pediatric urologists would improve patient care and efficiency of the healthcare system.

Association of Renal Function (Estimate Glomerular Filtration Rate) with the Number of Febrile Urinary Tract Infections in Children with Neurogenic Bladder

INTRODUCTION

 Our objective was to evaluate whether renal function, assessed as the estimated glomerular filtration rate (eGFR), is associated with the number of febrile urinary tract infections (FUTIs) in children diagnosed with neurogenic bladder (NB).

MATERIALS AND METHODS

 Clinical information of patients diagnosed with NB was prospectively collected between January 2013 and January 2022. Episodes of FUTI were recorded during the follow-up period, and the eGFR was calculated based on the serum cystatin C level. Grading (G1-G5) of chronic kidney disease (CKD) was conducted as described by the eGFR.

RESULTS

 In total, 463 children were included in the final analysis (265 males and 198 females; mean age: 23 months). The median follow-up time was 51 months. A total of 302 children had four or more FUTIs and 161 children had none to three FUTIs. The incidence of developing CKD G3 to G5 gradually increased from the first to third (1.3-2.4%) episodes of FUTI and drastically increased after four episodes (≥ 22.5%), with the incidence recorded to be 100% after eight FUTIs. The odds of CKD G3 to G5 in children with four FUTIs were 17.3 and 43.7 times greater after four and six FUTIs, respectively, than in children with one FUTI.

CONCLUSION

 This study showed that recurrent FUTIs are common in children with NB and that the risk of rapid progression to CKD G3 to G5 increases substantially after four or more FUTIs episodes.

The efficacy and safety of corticosteroids in pediatric kidney scar prevention after urinary tract infection: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Acute pyelonephritis (APN) in pediatric patients may lead to kidney scarring and is one of the main causes of permanent kidney damage. The incidence of kidney scarring after one febrile urinary tract infection (UTI) is reported to range from 2.8 to 15%, with the percentage rising to 28.6% after ≥ 3 febrile UTIs. Corticosteroids may have a role in the reduction of kidney scar formation and urine cytokine levels. The possible benefit of adjuvant corticosteroid administration in the reduction of kidney scar formation in children with APN has been recently examined in randomized controlled trials (RCTs).

OBJECTIVES

The aim of this meta-analysis was to provide a summary of the current literature about the efficacy and safety of adjuvant corticosteroid administration in the reduction of kidney scar formation in children with APN.

DATA SOURCES

An extensive literature search through major databases (PubMed/MEDLINE and Scopus) was carried out for RCTs from inception until October 12, 2022, investigating the efficacy and safety of adjuvant corticosteroids in preventing kidney scarring in children with APN. A risk ratio with 95% CI was used for dichotomous outcomes.

RESULTS

In total, 5 RCTs with 918 pediatric patients with APN were included in the study. Adjuvant corticosteroid treatment revealed a statistically significant reduction in kidney scarring (95% CI 0.42-0.95, p = 0.03), without increasing the risk of adverse events like bacteremia, prolonged hospitalization, or recurrence of UTI.

LIMITATIONS

There were limitations regarding sample size (n = 498 children), different classes of corticosteroids (methylprednisolone or dexamethasone), different routes of corticosteroid administration (intravenous or oral), and different day courses (3-day or 4-day course).

CONCLUSIONS

Adjuvant corticosteroid administration seems to have a beneficial effect on kidney scar reduction in children with APN. Future studies should focus on the evaluation of the efficacy and safety of corticosteroids in kidney scarring reduction after APN to strengthen the results of our study. A higher resolution version of the Graphical abstract is available as Supplementary information.

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.

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.

Risk factors associated with recurrent febrile urinary tract infection in children with neurogenic bladder who perform clean intermittent catheterization

OBJECTIVE

To identify the clinical and urodynamic risk factors associated with the development of recurrent febrile urinary tract infections (FUTIs) in children with neurogenic bladder (NB) who perform clean intermittent catheterization (CIC).

METHODS

Children with NB receiving CIC were prospectively enrolled from January to December 2019 and followed up prospectively for 2 years. All data were compared between occasional (0-1 FUTI) and recurrent FUTIs (≥2 FUTI) groups. In addition, the risk factors for recurrent FUTIs in children were evaluated.

RESULTS

Complete data from 321 children were analyzed. Occasional FUTIs occurred in 223 patients, and 98 patients experienced recurrent FUTIs. Univariate and multivariate analyses, showed late-initiation and low-frequency CIC, vesicoureteral reflux (VUR), small bladder capacity and low compliance, and detrusor overactivity were associated with an increased risk of recurrent FUTIs. Children with high-grade VUR (grades IV-V) had a higher risk of recurrent FUTIs than those with low-grade VUR (grades I-III) (odds ratio [OR]: 26.95 vs. OR: 4.78, p < 0.001).

CONCLUSIONS

Our study suggests that late-initiation and low-frequency CIC, VUR, small bladder capacity and low compliance, and detrusor overactivity were associated with recurrent FUTIs in patients with NB. In addition, high-grade VUR is a crucial risk factor for recurrent FUTIs.

Vesicoureteral Reflux: Current Care Trends and Future Possibilities

Although investigations over the past 2 decades have improved our understanding of the natural history of vesicoureteral reflux (VUR) and helped identify those at higher risk of both VUR itself as well as its potential severe sequelae, debate exists regarding key aspects of care, including when to perform diagnostic imaging and which patients benefit from continuous antibiotic prophylaxis. Artificial intelligence and machine learning have the potential to distill large volumes of granular data into practical tools that clinicians can use to guide diagnosis and management decisions. Surgical treatment, when indicated, remains highly effective and is associated with low morbidity.

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.

Building nomogram plots for predicting urinary tract infections in children less than three years of age

BACKGROUND AND PURPOSE

Urinary tract infections (UTIs) are the most common bacterial infection in young children. This study aimed to formulate nomogram plots for clinicians to predict UTIs in children aged <3 years by evaluating the risk factors for UTIs in these children.

METHODS

This retrospective study was conducted at a tertiary medical center from December 2017 to November 2020. Children less than three years of age were eligible for the study if they had undergone both urine culture and urinalysis during the study period. Mixed-effects logistic regression models with a stepwise procedure were used to determine the relationship between outcome (positive/negative UTI) and covariates of interest (e.g., weight percentile, laboratory) for each patient. Nomogram plots were constructed on the basis of significant factors. We repeated the analysis thrice to adapt it to three different medical settings: medical centers, regional hospitals, and local clinics.

RESULTS

In the medical center setting, the two most significant factors were urine leukocyte count ≥100 (OR =8.87; 95% CI (Confidence Interval), 4.135-19.027) and urine nitrite level (OR =8.809; 95% CI, 5.009-15.489). The two factors showed similar significance at the regional hospital and local clinic settings. Abnormal renal echo findings were positively correlated with UTI in the medical center setting (OR =2.534; 95% CI 1.757-3.655). Three nomogram plots for the prediction of UTIs were drawn for medical centers, regional hospitals, and local clinics.

CONCLUSION

Using the three nomogram plots, frontline doctors can formulate the probabilities of pediatric UTIs for better decision-making.

Risk factors for imaging abnormalities after the first febrile urinary tract infection in infants ≤3 months old: a retrospective cohort study

OBJECTIVES

To assess the association of clinical factors and investigation results (blood and urine) with imaging abnormalities (ultrasound of the kidneys, ureters and bladder; dimercaptosuccinic acid scan; and/or micturating cystourethrogram) and recurrent urinary tract infections (UTIs) in infants ≤3 months old presenting with their first febrile UTI.

METHODS

We conducted a retrospective cohort study of infants ≤3 months old with first febrile UTI admitted from 2010 to 2016. Multivariable logistic regression model was used to analyse the association of imaging abnormalities and recurrent UTI with covariates selected a priori: age at presentation, maximum temperature, duration of illness at presentation, interval between start of antibiotics and fever resolution, C-reactive protein, total white cell count on the full blood count, bacteraemia, white cell count on the urinalysis and non-Escherichia coli growth in the urine culture (non-E. coli UTI).

RESULTS

There were 190 infants but 12 did not undergo any imaging. Median age at presentation was 63 days (IQR 41-78). Twenty-four patients had imaging abnormalities. Non-E. coli UTI (adjusted OR (aOR) 5.01, 95% CI 1.65 to 15.24, p=0.004) was independently associated with imaging abnormalities, while bacteraemia (aOR 4.93, 95% CI 1.25 to 19.43, p=0.022) and non-E. coli UTI (aOR 5.06, 95% CI 1.90 to 13.48, p=0.001) were independently associated with recurrent UTI.

CONCLUSION

Non-E. coli UTI at the first febrile UTI in infants ≤3 months old may be useful in predicting imaging abnormalities while bacteraemia and non-E. coli UTI may be useful to predict recurrent UTI.

Urinary Tract Infection in Children

Symptoms of urinary tract infection (UTI) in young children are nonspecific and urine sampling is challenging. A safe and rapid diagnosis of UTI can be achieved with new biomarkers and culture of clean-catch urine, reserving catheterization or suprapubic aspiration for severely ill infants. Most guidelines recommend ultrasound assessment and use of risk factors to direct further management of children at risk of kidney deterioration. The increasing knowledge of the innate immune system will add new predictors and treatment strategies to the management of UTI in children. Long-term outcome is good for the majority, but individuals with severe scarring can develop hypertension and decline in kidney function.

Incidence rates and trends of childhood urinary tract infections and antibiotic prescribing: registry-based study in general practices (2000 to 2020)

Background

To improve the management of childhood urinary tract infections, it is essential to understand the incidence rates, testing and treatment strategy.

Methods

A retrospective study using data from 45 to 104 general practices (2000 to 2020) in Flanders (Belgium). We calculated the incidence rates (per 1000 person-years) of cystitis, pyelonephritis, and lab-based urine tests per age (< 2, 2-4, 5-9 and 10-18 years)) and gender in children and performed an autoregressive time-series analysis and seasonality analysis. In children with UTI, we calculated the number of lab-based urine tests and antibiotic prescriptions per person-year and performed an autoregressive time-series analysis.

Results

There was a statistically significant increase in the number of UTI episodes from 2000 to 2020 in each age group (p < 0.05), except in boys 2-4 years. Overall, the change in incidence rate was low. In 2020, the incidence rates of cystitis were highest in girls 2-4 years old (40.3 /1000 person-years 95%CI 34.5-46.7) and lowest in boys 10-18 (2.6 /1000 person-years 95%CI 1.8-3.6) The incidence rates of pyelonephritis were highest in girls 2-4 years (5.5, 95%CI 3.5-8.1 /1000 person-years) and children < 2 years of age (boys: 5.4, 95%CI 3.1-8.8 and girls: 4.9, 95%CI 2.7-8.8 /1000 person-years). In children 2-10 years, there was an increase in number of lab-based urine tests per cystitis episode per year and a decrease in total number of electronic antibiotic prescriptions per cystitis episode per year, from 2000 to 2020. In children with cystitis < 10 years in 2020, 51% (95%CI 47-56%) received an electronic antibiotic prescription, of which the majority were broad-spectrum agents.

Conclusions

Over the last 21 years, there was a slight increase in the number of UTI episodes diagnosed in children in Flemish general practices, although the overall change was low. More targeted antibiotic therapy for cystitis in accordance with clinical guidelines is necessary to reduce the use of broad-spectrum agents in children below 10 years.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-022-01784-x.

Primary Vesicoureteral Reflux and Renal Scarring

Vesicoureteral reflux (VUR) is the commonest congenital anomaly of urinary tract in children. It is mostly diagnosed after a urinary tract infection or during evaluation for congenital anomalies of the kidney and urinary tract. High-grade VUR, recurrent pyelonephritis, and delayed initiation of antibiotic treatment are important risk factors for renal scarring. The management of VUR depends on multiple factors and may include surveillance only or antimicrobial prophylaxis; very few patients with VUR need surgical correction. Patients with renal scarring should be monitored for hypertension and those with significant scarring should also be monitored for proteinuria and chronic kidney disease.

Epidemiology of Antibiotic Resistant Pathogens in Pediatric Urinary Tract Infections as a Tool to Develop a Prediction Model for Early Detection of Drug-Specific Resistance

Antibiotic resistance is an increasing problem, especially in children with urinary tract infections. Rates of drug-specific resistant pathogens were reported, and an easy prediction model to guide the clinical decision-making process for antibiotic treatment was proposed. Data on microbiological isolation from urinoculture, between January 2007−December 2018 at Istituto Gaslini, Italy, in patients aged <19 years were extracted. Logistic regression-based prediction scores were calculated. Discrimination was determined by the area under the receiver operating characteristic curve; calibration was assessed by the Hosmer and Lemeshow test and the Spiegelhalterz test. A total of 9449 bacterial strains were isolated in 6207 patients; 27.2% were <6 months old at the first episode. Enterobacteriales (Escherichia coli and other Enterobacteriales) accounted for 80.4% of all isolates. Amoxicillin-clavulanate (AMC) and cefixime (CFI) Enterobacteriales resistance was 32.8% and 13.7%, respectively, and remained quite stable among the different age groups. On the contrary, resistance to ciprofloxacin (CIP) (overall 9.6%) and cotrimoxazole (SXT) (overall 28%) increased with age. After multivariable analysis, resistance to AMC/CFI could be predicted by the following: sex; age at sampling; department of admission; previous number of bacterial pathogens isolated. Resistance to CIP/SXT could be predicted by the same factors, excluding sex. The models achieved very good calibration but moderate discrimination performance. Specific antibiotic resistance among Enterobacteriales could be predicted using the proposed scoring system to guide empirical antibiotic choice. Further studies are needed to validate this tool.

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.

Non-antibiotic Approaches to Preventing Pediatric UTIs: a Role for D-Mannose, Cranberry, and Probiotics?

PURPOSE OF REVIEW

While antibiotics have been a staple in the management and even prevention of urinary tract infections (UTIs), it is not without significant consequences due to intolerance and development of antibiotic resistant bacteria. These concerns necessitate alternatives to antibiotic use in the management of pediatric UTIs. This review seeks to evaluate non-antibiotic means of preventing UTI in the pediatric population.

RECENT FINDINGS

The search for preventative alternatives to antibiotics has included D-mannose, cranberry, and probiotics. These products similarly work through competitive inhibition of uropathogens in the urinary tract. Pediatric studies exist highlighting the use of cranberry extract/juice and probiotics in UTI prevention, although significant heterogeneity amongst studies have limited overarching recommendations for their use. Data of D-mannose use is extrapolated from adult literature. More studies are required in the utility of each treatment, with some emphasis on larger sample sizes and clarifications regarding dosing and formulation.

Risk Factors for the Development of Febrile Recurrences in Children with a History of Urinary Tract Infection

OBJECTIVE

To identify risk factors for febrile recurrence of urinary tract infections (UTIs) in children with a history of UTI.

STUDY DESIGN

We included 500 children aged 2-72 months with a history of UTI who were followed prospectively for approximately 2 years in the context of 2 previously conducted studies (Randomized Intervention for Children with Vesicoureteral Reflux and Careful Urinary Tract Infection Evaluation). We identified significant risk factors for febrile recurrences among children not receiving antimicrobial prophylaxis using univariate and multivariate logistic regression.

RESULT

On univariate analysis, non-Black race, febrile index UTI, bowel-bladder dysfunction, grade IV vesicoureteral reflux, renal scarring at baseline, and renal-bladder ultrasound abnormalities were associated with febrile recurrence. On multivariate analysis, the following variables independently increased the odds of febrile recurrences (OR; 95% CI): non-Black race (7.1; 1.5-127.9), bowel-bladder dysfunction (2.6; 1.1-5.3), febrile index UTI (2.5; 1.1-6.9), abnormalities on renal-bladder ultrasound scan (2.6; 1.2-5.6), grade IV vesicoureteral reflux (3.9; 1.4-10.5), and renal scarring at baseline (4.7; 1.2-19.1).

CONCLUSIONS

Non-Black race and grade IV vesicoureteral reflux increased the odds of febrile recurrence of UTI. Although our findings should stimulate other studies to further explore the relationship between race and UTIs, given that the link between race and UTI recurrence is unclear, race should not be used to make decisions regarding management of children with a UTI.

Risk factors for renal scarring and clinical morbidity in children with high-grade and low-grade primary vesicoureteral reflux

INTRODUCTION

Primary vesicoureteral reflux (VUR) is associated with urinary tract infections (UTIs) and renal damage. However, the importance of early diagnosis of VUR has been questioned. Moreover, most studies have few patients with high-grade VUR. Hence, we retrospectively analyzed a large cohort of patients with primary high-grade and low-grade VUR and assessed risk factors for renal damage and clinical morbidity.

MATERIAL AND METHODS

We included patients (<18 years) at diagnosis with low-grade (1-3) or high-grade (4-5) primary VUR and noted their clinical history and presence of hypertension, low eGFR (<60ml/in/1.73 m²), renal scarring (focal or generalised) and reduced differential renal function (DRF; <45%). Risk factors were assessed (in patients and renal units) by logistic regression and generalised estimating equation.

RESULTS

Of 399 primary VUR patients, 255 (64%) had high-grade VUR. Indications for voiding cystourethrogram were recurrent UTI (38%), first UTI (28%) and antenatal hydronephrosis (17%). At diagnosis, 252 (65%) had renal scars (focal in 170 [44%], generalised in 82 [21%]), and 188 (47%) had reduced DRF. High-grade VUR patients were more likely than low-grade VUR patients to have renal scarring (75% vs. 49%, p < 0.01), low eGFR (23% vs. 13%, p = 0.04) and significant hypertension (26% vs. 13%, p = 0.02). High-grade VUR was associated with generalised scars (odds ratio [OR] 11, p < 0.001), focal scars (OR 3.1, p < 0.001) and reduced DRF (OR 2.3, p < 0.001) shown in the table. Male sex was a risk factor for generalised scars (OR 2.3, p = 0.005). Focal scars were associated with recurrent UTIs (OR = 1.8, p = 0.004) and reduced DRF (OR 1.4, p = 0.027). Patients with multiple focal scars were diagnosed at an older age (2 years [1,4] than those with single scars (1.5 years [1,4] or no scars (1 year [0, 3]), p = 0.04).

DISCUSSION

The prevalence of renal damage and clinical morbidity at VUR diagnosis was higher than other studies. High-grade VUR patients had a greater prevalence of renal damage, low eGFR and hypertension than low-grade VUR patients and was a risk factor for focal scars, generalised scars and reduced DRF. Focal scars were independently associated with recurrent UTI. Those with multiple scars were diagnosed later than those with single scars or no scars.

CONCLUSIONS

High-grade VUR was associated with renal damage and clinical morbidity. Our study highlights the importance of diagnosing VUR early to identify patients who may warrant long-term follow-up and intervention to minimize morbidity.

[Antimicrobial resistance patterns in pediatric febrile urinary tract infection and empirical antibacterial therapy. An epidemiological study in secondary and tertiary care centers in the north-east of France in 2019-2020]

BACKGROUND

Febrile urinary tract infection (UTI) is a common health issue in pediatrics that can lead to serious infectious and renal complications, it requires early diagnosis and a targeted use of antibiotics. The aim of our study was to describe local bacterial agents causing febrile UTIs and their resistance patterns and confront the results with currently used empirical antibacterial therapy in pediatrics emergency departments in Strasbourg and Saverne.

PATIENTS AND METHODS

We used billing codes (international classification of diseases) to identify all inpatients treated for febrile UTIs in two French pediatric emergency departments between January 2019 and December 2020. Microbial results of urine cultures were retrieved from the laboratory information system.

RESULTS

Among 214 microbial results from 208 patients, the distribution of uropathogens was 82% Escherichia coli, with extended-spectrum beta-lactamase in 2.8%, 7% Enterococcus faecalis, 5% Klebsiella, 2% Proteus mirabilis. E. coli was resistant respectively to amoxicillin, amoxicillin/clavulanic acid and cotrimoxazol in 43, 33 and 14% of samples. A third-generation cephalosporin administered intravenously was mainly used (98%) as empirical treatment. Less than 2% of patients were treated with oral cephalosporin from the start.

CONCLUSION

We present the spectrum of uropathogens and susceptibility test results in pediatric UTIs as well as the susceptibility pattern of E. coli, a local treatment protocol was designed based on our results in conformity with national guidelines.

The RiVUR Study Outcomes and Implications on the Management of Vesicoureteral Reflux

The Randomized intervention for Vesicoureteral Reflux (RiVUR) study was an effort by the National Institute of Health to identify the most significant question on the management of vesicoureteral reflux (VUR), i.e. Did antibiotic prophylaxis reduce the incidence of recurrent urinary tract infections (UTI) in children with VUR? During the initial phases of the RiVUR study, several similar studies were performed that seemed to indicate a lack of benefit of antibiotic prophylaxis in VUR. However, few of these studies had the rigorous methodology and true randomization of the pediatric cohort that was studied in RiVUR. Additionally, many of these studies included children of wide age ranges and inconsistent assessments were used for identification of UTI and VUR. In 2011, the American Academy of Pediatrics (AAP) published a guideline statement for the evaluation of initial UTI in febrile children aged 2 to 24 months, which recommended against performing a Voiding Cystourethrogram (VCUG) in all children with a confirmed UTI. The goal of the AAP guidelines was to reduce the number of VCUGs being performed and potentially to reduce the number of children diagnosed with low grade VUR that seems to have low potential to cause renal injury. The RiVUR study included over 600 children identified with VUR after a 1^st or 2^nd febrile UTI randomized to prophylaxis with trimethoprim/sulfamethoxazole (TMP/SMZ), or placebo and followed over a study timeline for 2 years. Overall, a 50% reduction was noted in the incidence of recurrent febrile UTI with the utilization of prophylaxis as compared to placebo. Additional sub-group analyses have been performed on the cohorts of the study; these are also evaluated in this review to determine the overall impact of the RiVUR study on the current management of VUR.

Changes in Clinical Presentation and Renal Outcomes among Children with Febrile Urinary Tract Infection: 2005 vs 2015

PURPOSE

Recent studies have demonstrated trends of decreasing voiding cystourethrogram utilization rates and delayed vesicoureteral reflux diagnosis in some children. It is possible that such delays could lead to more children sustaining repeated episodes of febrile urinary tract infection, and potential kidney injury, prior to diagnosis and treatment.

MATERIALS AND METHODS

Using single institutional, cross-sectional cohorts of patients in 2 time periods (2005 and 2015), we compared clinical presentation and renal outcomes among patients 13 years and younger with history of febrile urinary tract infection presenting for initial voiding cystourethrogram. Outcomes included 1) recurrent urinary tract infection, 2) presence of vesicoureteral reflux, 3) grade of vesicoureteral reflux, and 4) renal scarring. Associations between year of presentation and outcomes of recurrent urinary tract infection and vesicoureteral reflux diagnosis were evaluated using multivariable logistic regression models. For the outcome of renal scarring, a logistic regression model was fitted for propensity score matched cohorts.

RESULTS

Compared to children presenting in 2005, those in 2015 had 3 times the odds of recurrent urinary tract infection (OR 3.01, 95% CI 2.18-4.16, p <0.0001). Time period was not associated with the odds of vesicoureteral reflux (OR 0.98, 95% CI 0.77-1.23, p=0.85). Those in 2015 were more likely to present with vesicoureteral reflux grade >3 (OR 2.22, 95% CI 1.13-4.34, p=0.02) but not vesicoureteral reflux grade >2 (OR 1.11, 95% CI 0.74-1.67, p=0.60). Renal scarring was more common among children presenting in 2015 (OR 2.9, 95% CI 1.03-8.20, p=0.04).

CONCLUSIONS

Compared to 2005, children presenting in 2015 for post-urinary tract infection voiding cystourethrogram have increased likelihood of recurrent urinary tract infection and renal scarring, despite similar likelihood of vesicoureteral reflux diagnosis.

Update of the EAU/ESPU guidelines on urinary tract infections in children

INTRODUCTION/BACKGROUND

Urinary tract infections (UTIs) are common in children and require appropriate diagnostic evaluation, management and follow-up.

OBJECTIVE

To provide a summary of the updated European Association of Urology (EAU) guidelines on Pediatric Urology, which were first published in 2015 in European Urology.

STUDY DESIGN

A structured literature review was performed of new publications between 2015 and 2020 for UTIs in children. The guideline was updated accordingly with relevant new literature.

RESULTS

The occurrence of a UTI can be the first indication of anatomical abnormalities in the urinary tract, especially in patients with a febrile UTI. The basic diagnostic evaluation should include sufficient investigations to exclude urinary tract abnormalities, but should also be as minimally invasive as possible. In recent years, more risk factors have been identified to predict the presence of these anatomical anomalies, such as a non-E. Coli infection, high grade fever and ultrasound abnormalities. When these risk factors are factored into the diagnostic work-up, some invasive investigations can be omitted in a larger group of children. In addition to the treatment of active UTIs, it is also essential to prevent recurrent UTIs and consequent renal scarring. With the increase of antimicrobial resistance good antibiotic stewardship is needed. In addition, alternative preventative measures such as dietary supplements, bladder and bowel management and antibiotic prophylaxis could decrease the incidence of recurrent UTI.

CONCLUSION

This paper is a summary of the updated 2021 EAU guidelines on Pediatric Urology. It provides practical considerations and flowcharts for the management and diagnostic evaluation of UTIs in children.

Urinary vanin-1 for predicting acute pyelonephritis in young children with urinary tract infection: a pilot study

BACKGROUND

Vanin-1, an epithelial glycosylphosphatidylolinositol (GPI)-anchored pantetheinase, is a valuable marker of renal injury.

PURPOSE

The aim of this study was to assess the predictive value of vanin-1 in acute pyelonephritis (APN) in comparison to the conventional serum inflammatory markers in children aged 1-24 months with the first episode of urinary tract infection (UTI).

MATERIAL AND METHODS

Urinary vanin-1, vanin-1/Cr ratio, WBC, CRP, PCT were analysed in 58 children with febrile UTI and in 18 children with non-febrile UTI. Febrile UTI group was divided into APN subgroup (n = 29) and non-APN subgroup (n = 29), based on the results of Tc-99m-ethylenedicysteine scan.

RESULTS

The mean vanin-1 level was higher in the APN group compared to the non-febrile UTI group (p = 0.02) and did not differ between APN and non-APN subgroup. In univariate analysis, vanin-1 (p = 0.042), CRP (p < 0.001), PCT (p < 0.001), and WBC (p = 0.022), were associated with APN, but only vanin-1 (p = 0.048) and CRP (p = 0.002) were independent markers of APN. In ROC analysis, vanin-1, with its best cut-off value of 16.53 ng/mL, had worse diagnostic profile (AUC 0.629, sensitivity 58,6%, specificity 63.8%) than CRP, PCT and WBC (AUC: 0.937; 0.880; 0.667, respectively).

CONCLUSIONS

Vanin-1 is not useful for predicting APN, since its diagnostic value is inferior to other conventional serum inflammatory markers.

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.

Girls and renal scarring as risk factors for febrile urinary tract infection after stopping antibiotic prophylaxis in children with vesicoureteral reflux

PURPOSE

To clarify the incidence of and risk factors for febrile urinary tract infection in children with persistent vesicoureteral reflux (VUR) after the discontinuation of continuous antibiotic prophylaxis (CAP), retrospective chart review was performed.

PATIENTS AND METHODS

Among children with primary VUR at 10 years of age or younger at presentation, those who had persistent VUR despite conservative management with CAP and who were subsequently followed after discontinuation of CAP were included. Kaplan-Meier curve and Cox's proportional hazard regression model were used for evaluation of the incidence of and risk factors for febrile urinary tract infection (fUTI) after stopping CAP.

RESULTS

Among 144 children (99 boys and 45 girls), fUTI developed in 34. The 5-year fUTI-free rate after discontinuation of CAP was 69.4%. On multivariate analyses, girls (p = 0.008) and abnormalities on nuclear renal scans (p = 0.0019), especially focal defect (p = 0.0471), were significant factors for fUTI. Although the fUTI-free rate was not different between children who had no or 1 risk factor, it was significantly lower in children with 2 risk factors than in those with no or 1 risk factor.

CONCLUSIONS

The present study revealed that girls and abnormal renal scan, especially focal defect, are risk factors for fUTI. Active surveillance without CAP for persistent VUR seems to be a safe option for children with no or 1 risk factor. Prophylactic surgery or careful conservative follow-up may be an option for girls with abnormal renal scan results if VUR persists under CAP.

Urine collection methods and dipstick testing in non-toilet-trained children

Urinary tract infection is a commonly occurring paediatric infection associated with significant morbidity. Diagnosis is challenging as symptoms are non-specific and definitive diagnosis requires an uncontaminated urine sample to be obtained. Common techniques for sampling in non-toilet-trained children include clean catch, bag, pad, in-out catheterisation and suprapubic aspiration. The pros and cons of each method are examined in detail in this review. They differ significantly in frequency of use, contamination rates and acceptability to parents and clinicians. National guidance of which to use differs significantly internationally. No method is clearly superior. For non-invasive testing, clean catch sampling has a lower likelihood of contamination and can be made more efficient through stimulation of voiding in younger children. In invasive testing, suprapubic aspiration gives a lower likelihood of contamination, a high success rate and a low complication rate, but is considered painful and is not preferred by parents. Urine dipstick testing is validated for ruling in or out UTI provided that leucocyte esterase (LE) and nitrite testing are used in combination.

Targeted Indication of Imaging for Detection of Vesicoureteric Reflux after Pediatric Febrile Urinary Tract Infections Based on a Multiparametric Computational Tool

OBJECTIVES

Diagnostic workup after febrile urinary tract infections (fUTIs) in children remains a matter of debate. The authors aimed to evaluate multiple parameters in order to design a predictive tool enabling a targeted indication of voiding cystourethrography (VCUG).

METHODS

Records of 383 consecutive children who underwent a VCUG as well as a dimercaptosuccinic-acid (DMSA) scan after febrile urinary tract infections (fUTIs) at a single institution between 04/2009 and 06/2014 were reviewed. Twenty parameters were recorded. After regression analysis, 6 parameters were incorporated into a computational tool aiming at a targeted indication of an eventual VCUG. The performance of the tool was prospectively tested on 100 patients.

RESULTS

Postpyelonephritic alterations on DMSA, duplex systems, age 1-3 y, duration of fever >3 d, >2 fUTIs before VCUG and abnormal sonography findings were identified as significant predictors (p < 0.05 each); the presence of bladder and bowel dysfunction (BBD) was negatively associated with vesicoureteric reflux (VUR). The resulting computational tool achieved an Area under the curve (AUC) of 0.686 (CI 0.633-0.740). Prospective evaluation (100 new patients) revealed a sensitivity of 85.1%, a specificity of 49.1%, a positive predictive value of 59.7% and a negative predictive value of 78.7%.

CONCLUSIONS

The differentiated indication of a VCUG based on the use of a tool was efficient in optimizing the specificity of the diagnostic algorithm after fUTIs. The tool outperformed other common clinical approaches in terms of VUR detection and VCUG frequency. After validation and further refinement in a multicentric approach, this strategy could significantly enhance VUR detection whilst reducing the number of VCUGs.

Corticosteroids to prevent kidney scarring in children with a febrile urinary tract infection: a randomized trial

BACKGROUND

To evaluate the efficacy of adjuvant systemic corticosteroids in reducing kidney scarring. A previous study suggested that use of adjuvant systemic corticosteroids reduces kidney scarring in children radiologically confirmed to have extensive pyelonephritis. Efficacy of corticosteroids for children with febrile urinary tract infection (UTI) has not been studied.

METHODS

Children aged 2 months to 6 years with their first febrile UTI were randomized to corticosteroids or placebo for 3 days (both arms received antimicrobial therapy); kidney scarring was assessed using ^99mTc-dimercaptosuccinic acid kidney scan 5-24 months after the initial UTI.

RESULTS

We randomized 546 children of which 385 had a UTI and 254 had outcome kidney scans (instead of the 320 planned). Rates of kidney scarring were 9.8% (12/123) and 16.8% (22/131) in the corticosteroid and placebo groups, respectively (p = 0.16), corresponding to an absolute risk reduction of 5.9% (95% confidence interval: - 2.2, 14.1).

CONCLUSION

While children randomized to adjuvant corticosteroids tended to develop fewer kidney scars than children who were randomized to receive placebo, a statistically significant difference was not achieved. However, the study was limited by not reaching its intended sample size.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov , NCT01391793, Registered 7/12/2011 Graphical abstract.

Immune Expression in Children With Vesicoureteral Reflux: A Pilot Study

OBJECTIVE

To perform an exploratory, descriptive pilot study of the systemic and local immune environment in patients with vesicoureteral reflux (VUR) and bladder-bowel dysfunction (BBD).

METHODS

Consecutive children with VUR undergoing intravesical ureteral reimplantation were enrolled. Patients were assessed for presence of BBD by reported patient history and validated questionnaire. Fresh blood and bladder tissue, collected at the time of surgery, were immediately processed for analysis. Immune cell compositions were determined via flow cytometry. Immune cell activation was also defined at the time of analysis. LegendPlex assay analysis was utilized to define levels of circulating chemokines and cytokines.

RESULTS

A total of 7 patients were enrolled. Although percentages of circulating immune cells in the blood of those with VUR/BBD and VUR alone were similar, within bladder tissue, VUR/BBD demonstrated increased immune infiltrates compared to VUR alone. Bladder sample analysis showed that B cells, and Effector Memory and Naïve T cell percentages were significantly increased in VUR/BBD patients compared to VUR patients. T cell expression of PD1 was increased in bladder tissues of BBD/VUR. Additionally, analysis of circulating neutrophils displayed significantly increased upregulation of PDL-1 in patients with VUR/BBD vs those with VUR only.

CONCLUSION

These pilot data suggest an immune-rich microenvironment is present within VUR. Severity of inflammation appeared to correlate with presence of BBD. This implies that targeting pelvic inflammation may be a novel therapy for children with VUR- or non-VUR-related BBD. Follow-up studies are currently underway.

Recurrent UTIs in Girls: What Is the Role of the Microbiome?

Urinary tract infections (UTIs) are one of the most common childhood bacterial infections. Recurrent UTIs can lead to renal scarring. Compared to boys, girls are more likely to develop scars as a result of recurrent UTIs. Therefore, there is a need to identify girls at high risk for recurrent UTIs and develop interventions to decrease the risk of recurrent UTIs. In this commentary, we will review the hypothesized pathophysiology of recurrent UTIs, explore the literature on the role of the microbiome in recurrent UTIs, focusing on female pediatric patients when able, and highlight the need for future research in this area.

Cost-Utility of Antimicrobial Prophylaxis for Treatment of Children With Vesicoureteral Reflux

Objective: Antimicrobial prophylaxis for children with vesicoureteral reflux (VUR) reduces recurrences of urinary tract infection (UTI) but requires daily antimicrobials for extended periods. We used a cost-utility model to evaluate whether the benefits of antimicrobial prophylaxis outweigh its risks and, if so, to investigate whether the benefits and risks vary according to grade of VUR. Methods: We compared the cost per quality-adjusted life-year (QALY) gained in four treatment strategies in children aged <6 years diagnosed with VUR after a first UTI, considering these treatment strategies: (1) prophylaxis for all children with VUR, (2) prophylaxis for children with Grade III or Grade IV VUR, (3) prophylaxis for children with Grade IV VUR, and (4) no prophylaxis. Costs and effectiveness were estimated over the patient's lifetime. We used $100,000/QALY gained as the threshold for considering a treatment strategy cost effective. Results: Based on current data and plausible ranges to account for data uncertainty, prophylaxis of children with Grades IV VUR costs $37,903 per QALY gained. Treating children with Grade III and IV VUR costs an additional $302,024 per QALY gained. Treating children with all grades of VUR costs an additional $339,740 per QALY gained. Conclusions: Treating children with Grades I, II, and III VUR with long-term antimicrobial prophylaxis costs substantially more than interventions typically considered economically reasonable. Prophylaxis in children with Grade IV VUR is cost effective.