Infant vesicoureteral reflux: a comparison between patients presenting with a prenatal diagnosis and those presenting with a urinary tract infection

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.

Prediction of Recurrent Urinary Tract Infection in Paediatric Patients by Deep Learning Analysis of 99mTc-DMSA Renal Scan

Purpose: Tc-99m dimercaptosuccinic acid (^99mTc-DMSA) renal scan is an important tool for the assessment of childhood urinary tract infection (UTI), vesicoureteral reflux (VUR), and renal scarring. We evaluated whether a deep learning (DL) analysis of ^99mTc-DMSA renal scans could predict the recurrence of UTI better than conventional clinical factors. Methods: the subjects were 180 paediatric patients diagnosed with UTI, who underwent immediate post-therapeutic ^99mTc-DMSA renal scans. The primary outcome was the recurrence of UTI during the follow-up period. For the DL analysis, a convolutional neural network (CNN) model was used. Age, sex, the presence of VUR, the presence of cortical defects on the ^99mTc-DMSA renal scan, split renal function (SRF), and DL prediction results were used as independent factors for predicting recurrent UTI. The diagnostic accuracy for predicting recurrent UTI was statistically compared between independent factors. Results: The sensitivity, specificity and accuracy for predicting recurrent UTI were 44.4%, 88.9%, and 82.2% by the presence of VUR; 44.4%, 76.5%, and 71.7% by the presence of cortical defect; 74.1%, 80.4%, and 79.4% by SRF (optimal cut-off = 45.93%); and 70.4%, 94.8%, and 91.1% by the DL prediction results. There were no significant differences in sensitivity between all independent factors (p > 0.05, for all). The specificity and accuracy of the DL prediction results were significantly higher than those of the other factors. Conclusion: DL analysis of ^99mTc-DMSA renal scans may be useful for predicting recurrent UTI in paediatric patients. It is an efficient supportive tool to predict poor prognosis without visually demonstrable cortical defects in ^99mTc-DMSA renal scans.

Efficacy of transcutaneous posterior tibial nerve stimulation in children with functional voiding disorders

AIMS

To assess the efficacy of transcutaneous posterior tibial nerve stimulation (TPTNS) on functional voiding disorder (FVD) and investigate the utility of urine biomarkers (UBs: nerve growth factor, transforming growth factor-beta 1, and tissue inhibitor of metalloproteinases 2) in diagnosis and follow-up.

METHODS

A total of 44 children were included to this randomized controlled trial prospectively. After randomization, 20 of 30 children with storage phase dysfunction those were unresponsive or noncompliant to medical treatment received TPTNS treatment (test group) and 10 children underwent TPTNS with no current (sham group) for 12 weeks. Fourteen healthy children constituted the nonsymptomatic group. UB levels, dysfunctional voiding and incontinence scoring system (DVISS), voiding diary, and quality of life (QoL) scores were assessed before and after treatment in the treatment groups.

RESULTS

QoL scores, overall and day-time DVISS scores were significantly decreased in both sham and test groups (p < 0.05). In addition to these findings, the frequency of incontinence and urgency episodes were also significantly reduced (p < 0.05) in the TPTNS treatment group. This effect in the test group was still valid 2 years after intervention. There was no significant difference in UBs measurements between treatment and nonsymptomatic groups and between pretreatment and posttreatment measurements of test and sham groups.

CONCLUSIONS

TPTNS is an efficient minimally invasive treatment in children with FVD who do not respond to medical treatment. TPTNS provides a significant improvement on episodes of frequency, episodes of incontinence, overall and day-time DVISS scores, and QoL scores. The effectiveness of treatment continues even at the end of the second year of intervention. UBs were not found to be predictive in terms of diagnosis and evaluating the treatment response.

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.

EAU-ESPU guidelines recommendations for daytime lower urinary tract conditions in children

The objective is to review the literature related to lower urinary tract (LUT) conditions in children to conceptualize general practice guidelines for the general practitioner, pediatrician, pediatric urologist, and urologist. PubMed was searched for the last 15-year literature by the committee. All articles in peer-review journal-related LUT conditions (343) have been retrieved and 76 have been reviewed extensively. Prospective trials were few and the level of evidence was low. Most of the recommendations have been done by committee consensus after extensive discussion of literature reports. History taking is an integral part of evaluation assessing day- and nighttime urine and bowel control, urgency, and frequency symptoms. Exclusion of any neurogenic and organic cause is essential. Uroflowmetry and residual urine determination are recommended in all patients to evaluate bladder emptying. Urodynamic studies are reserved for refractory or complicated cases. Urotherapy that aims to educate the child and family about bladder and bowel function and guides them to achieve normal voiding and bowel habits should initially be employed in all cases except those who have urinary tract infections (UTI) and constipation. Specific medical treatment is added in the case of refractory overactive bladder symptoms and recurrent UTIs.Conclusion: Producing recommendations for managing LUTS in children based on high-quality studies is not possible. LUTS in children should be evaluated in a multimodal way by minimal invasive diagnostic procedures. Urotherapy is the mainstay of treatment and specific medical treatment is added in refractory cases.What is Known:• Symptoms of the lower urinary tract may have significant social consequences and sometimes clinical morbidities like urinary tract infections and vesicoureteral reflux. In many children, however, there is no such obvious cause for the incontinence, and they are referred to as having functional bladder problems.What is New:• This review aims to construct a practical recommendation strategy for the general practitioner, pediatrician, pediatric urologist, and urologist for LUTS in children. Producing recommendations for managing LUTS in children based on high-quality studies is not possible. LUTS in children should be evaluated in a multimodal way by minimal invasive diagnostic procedures. Urotherapy is the mainstay of treatment and specific medical treatment is added in refractory cases.

Urinary tract infection in small children: the evolution of renal damage over time

BACKGROUND

Our objective was to analyze the evolution of kidney damage over time in small children with urinary tract infection (UTI) and factors associated with progression of renal damage.

METHODS

From a cohort of 1003 children <2 years of age with first-time UTI, a retrospective analysis of 103 children was done. Children were selected because of renal damage at index ^99mTc-dimercaptosuccinic acid (DMSA) scintigraphy at least 3 months after UTI, and a late DMSA scan was performed after at least 2 years. Damage was classified as progression when there was a decline in differential renal function (DRF) by ≥4%, as regression when there was complete or partial resolution of uptake defects.

RESULTS

Of 103 children, 20 showed progression, 20 regression, and 63 remained unchanged. There were no differences between groups regarding gender or age. In the progression group, 16/20 (80%) children had vesicoureteral reflux (VUR) grade III-V and 13 (65%) had recurrent UTI. In multivariable regression analysis, both VUR grade III-V and recurrent UTI were associated with progression. In the regression group, 16/20 (80%) had no VUR or grade I-II, and two (10%) had recurrent UTI.

CONCLUSIONS

Most small children with febrile UTI do not develop renal damage and if they do the majority remain unchanged or regress over time. However, up to one-fifth of children with renal damage diagnosed after UTI are at risk of renal deterioration. These children are characterized by the presence of VUR grades III-V and recurrent febrile UTI and may benefit from follow-up.

Incidence of Urinary Tract Infection Among Siblings of Children With Vesicoureteral Reflux

BACKGROUND

Siblings of children with vesicoureteral reflux (VUR) are at elevated risk of VUR. Screening siblings may identify VUR before a clinical illness such as a urinary tract infection (UTI), but the benefit of screening has not been demonstrated. We sought to determine the incidence of UTI among siblings, and we hypothesized that the sibling UTI rate is similar between screened and unscreened siblings.

METHODS

We performed a retrospective cohort analysis using insurance claims data (January 1, 2000, to December 31, 2009). Within each family, we identified the index VUR patient and siblings; we included siblings who were enrolled in the insurance plan from birth for at least 1 year. We identified siblings who were screened for VUR and/or had UTI. We investigated the association of screening and UTI, controlling for patient characteristics and clustering within families.

RESULTS

Among 617 siblings (associated with 497 index patients), 317 (51%) were girls. Median insurance enrollment time was 53.0 months, with 424 enrolled ≥3 years. Among those with 1 or 3 years of enrollment, the proportions of siblings who experienced UTI was 8.4% (52 of 617) and 10.4% (44 of 424), respectively. Median age at initial UTI was 32.7 months. A total of 223 siblings (36.0%) underwent sibling screening. There was no significant difference in UTI between screened and unscreened siblings (odds ratio 1.57, 95% confidence interval 0.87-2.85; P = .14). In multivariate analysis, screening was not associated with sibling UTI incidence (odds ratio 1.33, 95% confidence interval 0.68-2.60; P = .40).

CONCLUSIONS

Although UTI is relatively common among siblings of VUR patients, there was no statistically significant difference in UTI incidence between screened and unscreened siblings.

Update on childhood urinary tract infection and vesicoureteral reflux

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

Injectable biomaterials for incontinence and vesico-ureteral reflux: current status and future promise

Many injectable biomaterials have been produced as bulking agents for compression of urethral sphincter or ureteral orifice for treating adult stress incontinence or vesico-ureteral reflux in pediatrics. The agents being developed include glutaraldehyde crosslinked collagen, dextranomer/hyaluronic acid copolymer, pyrolytic carbon-coated zirconium oxide beads, polydimethyl-siloxane microparticles, polytetrafluoroethylene paste, autologous fats, autologous chondrocytes, and others. Though less invasive nature of these agents has gained their popularity as a quick solution of the disease symptoms, most of such treatments fail to produce good long-term efficacy. The failure is likely caused by the rapid degradation of material implants and the lack of tissue regeneration/integration properties. We thus believe that a good injectable biomaterial for incontinence should possess the following two properties: (1) to resist degradation and to reside in the implantation sites for a long period of time or (2) to enhance tissue regeneration and to establish permanent periurethral or subureteric tissue. Here we report some recent results for supporting this hypothesis.

[Evidence-based medicine and vesicoureteral reflux]

Vesicoureteral reflux (VUR) remains one of the most controversial subjects in paediatric urology. Much literature has been published on VUR, making the understanding of this anomaly and its treatments quite opaque. Evidence-Based Medicine (EBM) should be helpful to clarify the various VUR approaches contained in the 6224 titles found on Medline using the keywords "vesicoureteral reflux" and "vesicoureteric reflux". These articles were critically reviewed and graded according to EBM scorings, with regard to their methodological designs. This review of VUR literature suggests that most of our knowledge is based on publications with a low level of evidence, and that EBM lacks arguments to support recommendations for VUR diagnostic and treatment. It appears yet that antenatal dilatation of the urinary tract and symptomatic urinary tract infections (UTI) justify VUR screening. Surgery should be discussed in recurrent UTIs or deterioration of renal function. There is no consensus in case of persistent asymptomatic VUR regarding indication and duration of antibio-prophylaxis, and selection of radical treatment.

Voiding dysfunction: outcome in infants with congenital vesicoureteral reflux

OBJECTIVES

To assess the rate of development of voiding dysfunction as an outcome in patients with congenital vesicoureteral reflux.

METHODS

A computerized database was used to review the medical records of all patients with congenital reflux diagnosed before 6 months of age from 1988 to 2002. Only those infants with reflux who were followed up for at least 6 months past the age of toilet training were included. The parameters tabulated in this group included the presence of frequency, daytime wetting, urge incontinence, and infrequent voiding. The variables were summarized using contingency tables, and associations were evaluated using chi-square analysis and Fisher's exact test.

RESULTS

Of 342 patients (145 boys and 197 girls) with reflux, 67 (19.6%) developed voiding dysfunction (17.9% boys and 20.8% girls). No statistically significant difference was found between high grade (IV and V) and low grade (I and II) or grade III reflux, or between unilateral and bilateral reflux for the development of voiding dysfunction. Of the patients with reflux who had renal damage on dimercaptosuccinic acid scan, 24.3% of girls and 30.4% of boys developed voiding dysfunction, which was not significantly different from those without renal damage.

CONCLUSIONS

Approximately 20% of patients with vesicoureteral reflux diagnosed before 6 months of age demonstrated dysfunctional voiding after the age of toilet training. Voiding dysfunction occurred independent of sex, laterality, or severity of vesicoureteral reflux. Infants with renal damage on dimercaptosuccinic acid scan developed dysfunctional voiding only at a slightly greater, but not significantly different, rate than those with normal kidneys.

A MULTIVARIABLE ASSESSMENT OF RENAL SIZE AND GROWTH OF SCARRED KIDNEYS IN CHILDREN

PURPOSE

We applied a recently developed multivariable renal size nomogram to sonographic measurements of kidneys with known scarring to assess systematically their sizes and growth patterns compared to normal kidneys.

MATERIALS AND METHODS

We retrospectively reviewed renal sonograms of 138 kidneys (55 right and 83 left) with known scarring. The sizes of these scarred kidneys were compared to the 95% prediction limits calculated according to the multivariable renal size nomogram, adjusting for patient age, gender, race, weight and height. The growth of scarred kidneys was evaluated by fitting individual linear regression lines using serial sonographic measurements and comparing the results with normal predicted values.

RESULTS

The sizes of 89.1% of the right and 81.9% of the left scarred kidneys were within the 95% normal prediction limits. Only 17 of 138 of the scarred renal units showed smaller kidney sizes compared to the normal prediction limits. Serial sonographic measurements revealed that compared to normal predicted values, 24 of 60 left and 16 of 38 right scarred kidneys grew within +/- 1.0% annually of the boundaries of normal predicted values. Additionally, 8 left and 7 right scarred kidneys indicated a growth rate of more than 1% annually higher than the normal predicted values.

CONCLUSIONS

Multivariable analyses of renal sonographic measurements provided a dynamic picture of kidney well-being in children with renal scarring. We found that the majority of scarred kidneys were within the normal predicted limits, and a large proportion of these kidneys grew equally well compared to those with normal anatomy.

The sensitivity of antenatal ultrasound for predicting renal tract surgery in early childhood

OBJECTIVE

To establish the sensitivity of antenatal ultrasound for identifying the need for renal tract surgery in infancy and early childhood.

METHODS

A retrospective analysis of the surgical records in children under 5 years of age undergoing renal tract surgery in a regional pediatric urological surgery referral unit was carried out. All records between May 1997 and July 2002 were examined to assess the relationship between prenatal ultrasound findings and postnatal surgical pathology.

RESULTS

A total of 106 operations had been performed. The detection rate of multicystic renal dysplasia was 100% (17/17). The equivalent detection rates for pelviureteral junction obstruction, duplex renal system and vesicoureteral reflux were 82.8, 67 and 26.1%, respectively. None of the babies with renal tumors had abnormal antenatal ultrasound findings. The diagnosis of postnatal renal surgical pathology was made on the basis of prenatal scan findings in 59.6% of cases, while recurrent urinary tract infection led to the diagnosis in 26.0%.

CONCLUSIONS

Approximately 40% of children requiring surgery for renal tract pathology will have a normal antenatal ultrasound examination. The prevalence of abnormal antenatal ultrasound findings varies depending on the type of renal tract pathology. Despite these findings, the commonest indicator for surgery remains abnormal prenatal scan findings, followed by recurrent urinary tract infections.