Vesicoureteral reflux

Influence of microbiome in intraprostatic inflammation and prostate cancer

BACKGROUND

Chronic infection and inflammation have been linked to the development of prostate cancer. Dysbiosis of the oral and gut microbiomes and subsequent microbial translocation can lead to pathogenic prostate infections. Microbial-produced metabolites have also been associated with signaling pathways that promote prostate cancer development. A comprehensive discussion on the mechanisms of microbiome infection and the prostate microenvironment is essential to understand prostate carcinogenesis.

METHODS

Published studies were used from the National Center for Biotechnology Information (NCBI) database to conduct a narrative review. No restrictions were applied in the selection of articles.

RESULTS

Microbiome-derived short-chain fatty acids (SCFAs) have been found to upregulate multiple signaling pathways, including MAPK and PI3K, through IGF-1 signaling and M2 macrophage polarization. SCFAs can also upregulate Toll-like receptors, leading to chronic inflammation and the creation of a pro-prostate cancer environment. Dysbiosis of oral microbiota has been correlated with prostate infection and inflammation. Additionally, pathogenic microbiomes associated with urinary tract infections have shown a link to prostate cancer, with vesicoureteral reflux potentially contributing to prostate infection.

CONCLUSIONS

This review offers a comprehensive understanding of the impact of microbial infections linked to intraprostatic inflammation as a causative factor for prostate cancer. Further studies involving the manipulation of the microbiome and its produced metabolites may provide a more complete understanding of the microenvironmental mechanisms that promote prostate carcinogenesis.

Nadir Creatinine in Congenital Anomalies of the Kidney and Urinary Tract (CAKUT): A Single-Center Experience

BACKGROUND/OBJECTIVES

Congenital anomalies of the kidney and urinary tract (CAKUT) are the main cause of chronic kidney disease (CKD) requiring renal replacement therapy (RRT) in children, being the leading cause (50-70%) of end-stage renal disease (ESRD) in children and young adults. Our study aimed to assess the natural evolution of various antenatally diagnosed renal malformations and to identify potential prognostic factors to guide the therapeutic management of patients with CAKUT.

METHODS

We conducted a retrospective study on 205 children with CAKUT. For each patient, analyzing their medical records, we established the nadir value of serum creatinine, defined as the lowest creatinine level during the first year of life. We assessed the value of nadir creatinine as a prognostic marker in patients with CAKUT, and using an ROC curve, we also determined a threshold value of nadir creatinine that predicted progression to ESRD.

RESULTS

The male-to-female ratio was 2.8 to 1. The mean gestational age at detection was 29.85 weeks (±6.71). A total of 36 patients (17.6%) had impaired renal function, of which 8 (3.9% of the total) progressed to ESRD. The mean nadir creatinine in patients with ESRD was 1.39 mg/dL. A nadir creatinine cut-off of 0.98 mg/dL had high sensitivity and specificity in identifying patients with progression to ESRD, with an AUC of 0.95 and a 95% confidence interval between 0.86 and 1.05 mg/dL.

CONCLUSIONS

Our results support the value of nadir creatinine in predicting progression to ESRD, consistent with previously published data.

Urology Mythbusters: Does prevalence of vesicoureteral reflux in children vary by race?

In this edition of Mythbusters, we examine the premise that prevalence of vesicoureteral reflux (VUR) in children varies by race. Specifically, we consider whether there is evidence supporting the contention that VUR is more common in White children and less common in Black children. Statements regarding the lower prevalence of VUR in Black children are ubiquitous in both research papers and reviews. Many of the references cited in support of these statements do not actually support the existence of racial variation in VUR, due to uncontrolled single-arm study designs, highly selected samples at risk for bias, or simply not addressing VUR prevalence at all. There is a small group of studies which directly compared VUR prevalence among children undergoing cystography, and these studies have found VUR to be less common among Black children compared to White children. However, the results of such papers can only be considered in the context of a system in which systemic bias and racism may impact access and care delivery in profound ways. Given that race is a social construct that bears little relationship to shared genetic ancestry or underlying biological characteristics, these findings must be approached with extreme caution. The goals of pediatric urological care should be to confer equitable care to all young children regardless of race.

The Intrarenal Reflux Diagnosed by Contrast-Enhanced Voiding Urosonography (ceVUS): A Reason for the Reclassification of Vesicoureteral Reflux and New Therapeutic Approach?

Vesicoureteral reflux (VUR) is defined as the urine backflow from the urinary bladder to the pyelo-caliceal system. In contrast, intrarenal reflux (IRR) is the backflow of urine from the renal calyces into the tubulointerstitial space. VURs, particularly those associated with IRR can result in reflux nephropathy when accompanied by urinary tract infection (UTI). The prevalence of IRR in patients with diagnosed VUR is 1-11% when using voiding cystourethrography (VCUG), while 11.9-61% when applying the contrast-enhanced voiding urosonography (ceVUS). The presence of IRR diagnosed by VCUG often correlates with parenchymal scars, when diagnosed by a 99mTc dimercaptosuccinic acid scan (DMSA scan), mostly in kidneys with high-grade VURs, and when diagnosed by ceVUS, it correlates with the wide spectrum of parenchymal changes on DMSA scan. The study performed by both ceVUS and DMSA scans showed IRRs associated with non-dilated VURs in 21% of all detected VURs. A significant difference regarding the existence of parenchymal damage was disclosed between the IRR-associated and IRR-non-associated VURs. A higher portion of parenchymal changes existed in the IRR-associated VURs, regardless of the VUR grade. That means that kidneys with IRR-associated VURs represent the high-risk group of VURs, which must be considered in the future classification of VURs. When using ceVUS, 62% of places where IRR was found were still unaffected by parenchymal changes. That was the basis for our recommendation of preventive use of long-term antibiotic prophylaxis until the IRR disappearance, regardless of the VUR grade. We propose a new classification of VURs using the ceVUS method, in which each VUR grade is subdivided based on the presence of an IRR.

Quantification of vesicoureteral reflux using machine learning

INTRODUCTION

The radiographic grading of voiding cystourethrogram (VCUG) images is often used to determine the clinical course and appropriate treatment in patients with vesicoureteral reflux (VUR). However, image-based evaluation of VUR remains highly subjective, so we developed a supervised machine learning model to automatically and objectively grade VCUG data.

STUDY DESIGN

A total of 113 VCUG images were gathered from public sources to compile the dataset for this study. For each image, VUR severity was graded by four pediatric radiologists and three pediatric urologists (low severity scored 1-3; high severity 4-5). Ground truth for each image was assigned based on the grade diagnosed by a majority of the expert assessors. Nine features were extracted from each VCUG image, then six machine learning models were trained, validated, and tested using 'leave-one-out' cross-validation. All features were compared and contrasted, with the highest-ranked then being used to train the final models.

RESULTS

F1-score is a metric that is often used to indicate performance accuracy of machine learning models. When using the highest-ranked VCUG image features, F1-scores for the support vector machine (SVM) and multi-layer perceptron (MLP) classifiers were 90.27 % and 91.14 %, respectively, indicating a high level of accuracy. When using all features combined, F1 scores were 89.37 % for SVM and 90.27 % for MLP.

DISCUSSION

These findings indicate that a distorted pattern of renal calyces is an accurate predictor of high-grade VUR. Machine learning protocols can be enhanced in future to improve objective grading of VUR.

Vesicoureteral reflux severity is not associated with unplanned urinary catheterization or length of hospital stay after ureteroneocystostomy

INTRODUCTION

Vesicoureteral reflux (VUR) is a common urologic condition affecting approximately 1% of all children. Surgical success often depends on the grade of VUR, as patients with grades 4 or 5 have been have a greater risk for postoperative complications. Unplanned urinary catheter placement (UCP) postoperatively and prolonged length of hospital stay (LOS) are indicative of unexpected complications. The association between VUR severity and such metrics remain unclear.

OBJECTIVE

The study's objective is to determine if the severity of VUR is associated with higher rates of UCP or prolonged LOS after ureteroneocystostomy (UNC).

STUDY DESIGN

The 2020 National Surgical Quality Improvement Program Pediatric database was analyzed for patients with VUR. A total of 1742 patients were initially evaluated with 1373 meeting exclusion criteria. The patients were divided into 3 groups of varying voiding cystourethrogram (VCUG) or radionuclide cystogram (RNC) severity: VCUG Grade 1 or RNC Grade 1 (Group A), VCUG Grade 2 or 3 or RNC Grade 2 (Group B), and VCUG Grade 4 or 5 or RNC Grade 3 (Group C). Basic statistical analysis was performed, and logistic regression was performed with both UCP and LOS as dependent variables.

RESULTS

Among the 1373 patients, 2.9% were included in Group A, 32.5% were in Group B, and 64.6% were in Group C. Significant differences were found among the groups for mean age, gender, inpatient status, rate of congenital malformation, ureteral stents, and ASA classification. Regarding surgical treatment, differences were also found comparing mean operative time, LOS, laterality and type of procedure, urine culture results, rates of UTI, surgical site infections, postoperative returns to the emergency department, and unplanned procedures and catheterization. Multivariate analysis demonstrated no significant association between the rate of UCP and VUR severity, while postoperative UTI and unplanned procedure were both independent factors associated with UCP postoperatively. Additionally, postoperative UTI, ASA classification, mean operation time, ureteral stent placement, unplanned procedure, and UCP were independent factors found to contribute to LOS.

CONCLUSION

Greater VUR severity does not appear to increase the need for catheterization or prolong hospital stay, while the development of a UTI postoperatively or having an additional unplanned procedure are associated with an increased likelihood of both. The postoperative course after UNC also appears to be influenced more so by other factors such as the operative approach and whether complications arise.

The Utility of Noninvasive Urinary Biomarkers for the Evaluation of Vesicoureteral Reflux in Children

Vesicoureteral reflux (VUR) is one of the most important disorders encountered in pediatric nephrology due to its frequency and potential evolution to chronic kidney disease (CKD). The aim of our study was to identify noninvasive and easy-to-determine urinary markers to facilitate the diagnosis and staging of VUR. We performed a cross-section study including 39 patients with VUR followed over three years (August 2021-September 2023) and 39 children without urinary disorder (the control group). We measured the urinary concentration of interleukin-6 (IL-6), cathelicidin (LL-37), and neutrophil gelatinase-associated lipocalin (NGAL) in VUR and healthy controls. Moreover, we analyzed the correlation between these biomarkers and the presence of renal scars (RS), reflux nephropathy (RN), and CKD. The NGAL concentrations were significantly higher in patients with VUR than in the controls (p = 0.02). Regarding the severity of the reflux, NGAL/creatinine and LL-37/creatinine were positively correlated with severe reflux (p = 0.04, respectively, p = 0.02). In patients with VUR and RS, LL-37/creatinine was significantly lower (p = 0.01). LL-37/creatinine with an AUC of 0.71 and NGAL/creatinine with an AUC of 0.72 could be acceptable diagnostic tests for severe VUR. In conclusion, urinary IL-6, NGAL, and LL-37 could serve as valuable markers for diagnosing and predicting outcomes in patients with VUR and RN.

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

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

Efficacy and safety of Hyadex for treatment of vesicoureteral reflux: a multicenter experience

OBJECTIVE

This study was performed to evaluate the efficacy and safety of dextranomer/cross-linked hyaluronic acid (Hyadex) in patients with a clinical diagnosis of vesicoureteral reflux (VUR).

METHODS

In this cross-sectional multicenter observational study, Hyadex was used in four different centers for the endoscopic treatment of VUR from 2020 to 2022. The study involved 74 patients (93 renal units) who were diagnosed with VUR according to voiding cystourethrography (VCUG) findings and were considered suitable for subureteric endoscopic treatment. The follow-up time (control VCUG time) was 3 months.

RESULTS

In the VCUG evaluation, grade I VUR was found in 13 renal units, grade II in 23 renal units, grade III in 42 renal units, and grade IV in 12 renal units. The success rates of Hyadex treatment according to the degree of VUR were as follows: 84.6% for grade I, 82.6% for grade II, 71.4% for grade III, and 66.0% for grade IV. No major complications were observed.

CONCLUSION

Endoscopic subureteric Hyadex injection had high success rates in appropriately selected patients with VUR and may be used as the first-line treatment for children with VUR.

Long term outcomes of Cohen’s cross trigonal reimplantation for primary vesicoureteral reflux in poorly functioning kidney

BACKGROUND

Open ureteric reimplantation by cross trigonal technique described by Cohen is considered a common surgical option for correction of vesicoureteral reflux (VUR). There is a lack of evidence in literature though for what happens to such kidneys, in the long run, particularly those which are poorly functioning.

AIM

To assess the long-term outcomes of ureteric reimplantation in poorly functioning kidneys in children with unilateral primary VUR.

METHODS

Children with unilateral primary VUR and a relative renal function of less than 35% who underwent open or laparoscopic ureteric reimplantation between January 2005 and January 2017 were included in the study. Patients who had a follow up of less than five years were excluded. Preoperative evaluation consisted of a voiding cystourethrogram and Dimercaptosuccinic acid (DMSA) scan. In the follow-up period, patients underwent a diuretic scan at 6 weeks and 6 months. Follow up ultrasound was done for change in grade of hydronephrosis and retrovesical ureteric diameter. Subsequent follow up was done at 6 monthly intervals with evaluation for proteinuria and hypertension and any recurrent urinary tract infection (UTI). For assessment of cortical function, DMSA was repeated annually for 5 years after surgery. A paired-samples t-test was used to test the mean difference of DMSA between pre-post observations.

RESULTS

During this period, 36 children underwent ureteric reimplantation for unilateral primary VUR. After excluding those with insufficient follow-up, 31 were included in the analysis. Most of the patients were males (n = 26/31, 83.8%). Patient’s age (mean ± SD, range) was 5.21 ± 3.71, 1-18 years. The grades of VUR were grade II (1 patient), grade III (8 patients), grade IV (10 patients), and grade V (12 patients). The pre and postoperative DMSA was 24.064 ± 12.02 and 24.06 ± 10.93, which was almost the same (statistically equal, paired-samples t-test: P = 0.873). The median (range) follow-up duration was 82 (60-120) mo. One patient had persistent reflux after surgery (preoperative: grade IV, postoperative: grade III), and the very same patient developed recurrent UTI. The difference in the preoperative and postoperative DRF was less than 10% in 29 patients. In one patient, the DRF decreased by 17% (22% to 05%) while in another patient, the DRF increased by 12% (25% to 37%) after surgery. None of the patients had an increase in scarring after surgery. 15% of patients were hypertensive before surgery and all of them continued to be hypertensive after surgery while none developed hypertension after surgery. None of the patients had significant proteinuria (> 150 mg/d) during the follow-up period.

CONCLUSION

Children with unilateral primary VUR and poorly functioning kidney maintain the renal function over the long term in most cases. Hypertension and proteinuria do not progress over time in these patients.

Vesicoureteral Reflux and Innate Immune System: Physiology, Physiopathology, and Clinical Aspects

Vesicoureteral reflux represents one of the most concerning topics in pediatric nephrology due to its frequency, clinical expression with the potential to evolve into chronic kidney disease, and last but not least, its socio-economic implications. The presence of vesicoureteral reflux, the occurrence of urinary tract infections, and the development of reflux nephropathy, hypertension, chronic kidney disease, and finally, end-stage renal disease represent a progressive spectrum of a single physiopathological condition. For the proper management of these patients with the best clinical outcomes, and in an attempt to prevent the spread of uropathogens' resistance to antibacterial therapy, we must better understand the physiopathology of urinary tract infections in patients with vesicoureteral reflux, and at the same time, we should acknowledge the implication and response of the innate immune system in this progressive pathological condition. The present paper focuses on theoretical aspects regarding the physiopathology of vesicoureteral reflux and the interconditionality between urinary tract infections and the innate immune system. In addition, we detailed aspects regarding cytokines, interleukins, antimicrobial peptides, and proteins involved in the innate immune response as well as their implications in the physiopathology of reflux nephropathy. New directions of study should focus on using these innate immune system effectors as diagnostic and therapeutic tools in renal pathology.

Vesicoscopic ureteral reimplantation with a modified Glenn-Anderson technique for vesicoureteral reflux

INTRODUCTION

Vesicoureteral reflux (VUR), commonly referred to as urinary reflux, is one of the most common congenital urological anomaly to occur during childhood. Historically, open vesicoureteral reimplantation has been the gold standard in the surgical treatment of VUR. Currently, vesicoscopic ureteral reimplantation is used as a minimally invasive alternative to open ureteral reimplantation. Most vesicoscopic procedures are performed using the transtrigonal Cohen technique. As a non-transtrigonal technique, the vesicoscopic Politano-Leadbetter technique is also performed, but requires dissection outside the bladder under a narrow surgical field, and in boy carries a risk of vas deferens injury.

OBJECTIVE

This study evaluated surgical outcomes and perioperative findings for vesicoscopic ureteral reimplantation using a modified Glenn-Anderson technique in children with VUR.

STUDY DESIGN

Eighteen consecutive children who underwent vesicoureteral ureteral reimplantation using a modified Glenn-Anderson technique were included in this study. The surgical procedure was explained and surgical outcomes and perioperative findings were evaluated.

RESULTS

Patients comprised 9 boys and 9 girls with 29 cases of ureteral reflux (7 unilateral cases, 11 bilateral cases). All procedures were performed laparoscopically, with no cases requiring conversion to open surgery. Median operative time was 143 min for unilateral VUR and 194 min for bilateral VUR. Only one case showed a complication (Clavien-Dindo grade 1). The remaining 17 cases showed no complications, with removal of the urethral catheter and discharge 2 days postoperatively. Seventeen of the 18 cases underwent postoperative voiding cystourethrography, showing no VUR in all cases.

DISCUSSION

Vesicoscopic ureteral reimplantation is a minimally invasive alternative to open surgery, with most procedures performed using a transtrigonal Cohen technique. Regardless of whether the surgery is open or laparoscopic, a disadvantage of the Cohen technique is that postoperative transureteral treatment may not be possible. The Politano-Leadbetter technique has been reported as a non-transtrigonal technique. However, this requires dissection outside the bladder under a narrow surgical field, and carries a risk of vas deferens injury in boys. In this study, vesicoscopic ureteral reimplantation using a modified Glenn-Anderson technique provided good surgical outcomes with minimal perioperative complications and easy manipulation under a wide field of view.

CONCLUSION

Although many minimally invasive treatments are available, vesicoscopic ureteral reimplantation using a modified Glenn-Anderson technique is safe and effective for patients with VUR 4 years old. To demonstrate the further utility of this procedure, long-term outcomes and safety evaluations are needed in a larger number of cases.

Evaluation of renal oxygenation by near-infrared spectroscopy during endoscopic injection of bulking agents in children with vesicoureteral reflux

BACKGROUND

Near infrared spectroscopy (NIRS) is the measuring of regional tissue oxygenation (rSO2) by interpreting oxyhemoglobin and deoxyhemoglobin signals that come back by transmitting near infrared light to tissues. The effect of endourological interventions on renal perfusion in children is largely unknown.

AIMS

To evaluate the effects of endoscopic injection of bulking agents (EIBA) for vesicoureteral reflux (VUR) on renal oxygenation (RO) using renal NIRS monitoring, which shows renal perfusion and oxygenation changes.

STUDY DESIGN

Case-control study.

METHODS

Group I had bilateral inguinal surgery, Group II cystoscopy, and Group III, EIBA for VUR with 30 patients in each group. During the operation, vital signs, peripheral oxygen saturation, end-tidal carbon dioxide, and renal regional oxygen saturation index (rSO2) values by bilateral renal NIRS monitoring were recorded. NIRS values before induction (T0) to postoperative (Tend) were determined. A 20% or more reduction in renal rSO2 (%20↓rSO2) was considered significant. Group III was also evaluated as subgroup III-A (not having "%20↓rSO2") and subgroup III-B ("%20↓rSO2").

RESULTS

The rSO2 decrease was observed in the first 5 min for both sides in group III. The most significant drop was at T30 for the right kidney and a significant decrease in rSO2, 20% or more, was observed in 6 renal units of 4 patients having higher SFU grading and renal scar in group III.

CONCLUSION

EIBA may transitionally impair renal oxygenation. Higher SFU grading and renal scar may increase the risk of renal hypoxia during EIBA.

CAKUT: A Pediatric and Evolutionary Perspective on the Leading Cause of CKD in Childhood

The global prevalence of chronic kidney disease (CKD) is increasing rapidly, due to increasing environmental stressors through the life cycle. Congenital anomalies of kidney and urinary tract (CAKUT) account for most CKD in children, with a spectrum that can lead to kidney failure from early postnatal to late adult life. A stressed fetal environment can impair nephrogenesis, now recognized as a significant risk factor for the development of adult CKD. Congenital urinary tract obstruction is the leading cause of CKD due to CAKUT and can itself impair nephrogenesis as well as contribute to progressive nephron injury. Early diagnosis by ultrasonography in fetal life by an obstetrician/perinatologist can provide important information for guiding prognosis and future management. This review focuses on the critical role played by the pediatrician in providing timely evaluation and management of the patient from the moment of birth to the transfer to adult care. In addition to genetic factors, vulnerability of the kidney to CKD is a consequence of evolved modulation of nephron number in response to maternal signaling as well as to susceptibility of the nephron to hypoxic and oxidative injury. Future advances in the management of CAKUT will depend on improved biomarkers and imaging techniques.

Color Doppler Ultrasound's Utility in Detecting Vesicoureteral Reflux Using the Ureteral Jet Angle

OBJECTIVES

This study hypothesizes using color Doppler ultrasound to measure ureteral jet angles (UJA) as a diagnostic screening tool for reflux.

METHODS

The present prospective cohort study included 122 patients and 238 renal unit pediatric patients suspected of VUR who presented to our hospital between 2019 and 2021. All patients underwent ultrasonography and VCUG, and the UJA was measured color Doppler evaluation of the ureteral jet. The UJA was compared with the VCUG findings in patients with and without reflux. SPSS 26 was used to analyze the data.

RESULTS

A total of 96 patients and 139 renal units exhibited reflux. The mean ureteral jet angle in refluxing units was 60.47 + 16.66 degrees, whereas, it was 42.59 + 13.26 degrees in non-refluxing units, a significant difference between the two groups (P < .001). The mean ureteral jet angle was 42.59, 45.89, 60.32, 68.23, and 56.16, for reflux grading from 0 to 5 (except grade 1), respectively. The angle value in each reflux grade increased significantly except for grade 5. For reflux detection (grade I-V), a cut-off angle of 50 degrees was associated with sensitivity and specificity of 70 and 79, respectively. Grade IV/V reflux can be diagnosed with a sensitivity of 70% and specificity of 84% using a cut-off angle of 68 degrees or greater.

CONCLUSIONS

UJA detection via color Doppler ultrasound demonstrates high accuracy, is non-invasive method can be utilized as an alternative primary diagnostic tool or in follow-up cases of VUR in children.

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.

Disease mechanisms of monogenic congenital anomalies of the kidney and urinary tract American Journal of Medical Genetics Part C

Congenital Anomalies of the Kidney and Urinary Tract (CAKUT) is a developmental disorder of the kidney and/or genito-urinary tract that results in end stage kidney disease (ESKD) in up to 50% of children. Despite the congenital nature of the disease, CAKUT accounts for almost 10% of adult onset ESKD. Multiple lines of evidence suggest that CAKUT is a Mendelian disorder, including the observation of familial clustering of CAKUT. Pathogenesis in CAKUT is embryonic in origin, with disturbances of kidney and urinary tract development resulting in a heterogeneous range of disease phenotypes. Despite polygenic and environmental factors being implicated, a significant proportion of CAKUT is monogenic in origin, with studies demonstrating single gene defects in 10%-20% of patients with CAKUT. Here, we review monogenic disease causation with emphasis on the etiological role of gene developmental pathways in CAKUT.

Obesity Prediction with EHR Data: A deep learning approach with interpretable elements

Childhood obesity is a major public health challenge. Early prediction and identification of the children at an elevated risk of developing childhood obesity may help in engaging earlier and more effective interventions to prevent and manage obesity. Most existing predictive tools for childhood obesity primarily rely on traditional regression-type methods using only a few hand-picked features and without exploiting longitudinal patterns of children's data. Deep learning methods allow the use of high-dimensional longitudinal datasets. In this paper, we present a deep learning model designed for predicting future obesity patterns from generally available items on children's medical history. To do this, we use a large unaugmented electronic health records dataset from a large pediatric health system in the US. We adopt a general LSTM network architecture and train our proposed model using both static and dynamic EHR data. To add interpretability, we have additionally included an attention layer to calculate the attention scores for the timestamps and rank features of each timestamp. Our model is used to predict obesity for ages between 3-20 years using the data from 1-3 years in advance. We compare the performance of our LSTM model with a series of existing studies in the literature and show it outperforms their performance in most age ranges.

The clinical application of ultrasonography with superb microvascular imaging-a review

Superb microvascular imaging (SMI) is among the latest doppler ultrasound methods. It uses an advanced clutter filter to eliminate artifacts caused by breathing, movement and retains the low-speed blood signals in microvessels. The great advantage of SMI is that it can intuitively detect very slow blood signals in microvessels, providing clinicians with more significant information about flow distribution in the target area. Therefore, it is speculated that SMI has important application value. The purpose of this article is to outline the application of SMI in different parts of the body.

The causes and consequences of paediatric kidney disease on adult nephrology care

Adult nephrologists often look after patients who have been diagnosed with kidney disease in childhood. This does present unique challenges to the adult nephrologist, who may be unfamiliar with the underlying cause of kidney disease as well as the complications of chronic kidney disease (CKD) that may have accumulated during childhood. This review discusses common causes of childhood CKD, in particular congenital anomalies of the kidney and urinary tract (CAKUT), autosomal dominant tubulointerstitial kidney disease (ADTKD), polycystic kidney disease, hereditary stone disease, nephrotic syndrome and atypical haemolytic uraemic syndrome. The long-term consequences of childhood CKD, such as the cardiovascular consequences, cognition and education as well as bone health, nutrition and growth are also discussed.

Vesicoureteral Reflux in Children with Urinary Tract Infections in the Inpatient Setting in Taiwan

Purpose

Children with vesicoureteral reflux (VUR) are at an increased risk of recurrent urinary tract infections (UTIs). Early detection and treatment of VUR are important to prevent renal function impairment. Therefore, the aims of this study were to determine the epidemiology of VUR and to identify clinical factors associated with VUR in Taiwanese children with a first documented UTI.

Patients and Methods

We conducted this nationwide retrospective study using the Longitudinal Health Insurance Database 2010. Children ≤6 years of age who were admitted and received intravenous antibiotics for a newly diagnosed UTI were included. Multivariate logistic regression analysis was used to identify independent factors associated with VUR.

Results

Overall, 388 (10.2%) of the children had VUR. The median (interquartile range) age at diagnosis of VUR was 0.5 (0.3–1.3) years. Among the children with VUR, the age at first UTI and the age at diagnosis of VUR were significant lower in the males than in the females. Age ≤1 year at the first UTI (odds ratio (OR), 1.3; 95% confidence interval (CI): 1.0–1.7), renal agenesis and dysgenesis (OR, 4.1; 95% CI: 1.3–13.1), hydronephrosis (OR, 2.2; 95% CI: 1.7–2.9), duplex collecting system/ectopic kidney/ectopic ureter (OR, 13.0; 95% CI: 8.1–20.8), neuropathic bladder (OR, 4.7; 95% CI: 2.0–11.1) and spina bifida (OR, 5.9; 95% CI: 1.3–27.8) were independent factors for VUR.

Conclusion

The children with VUR were more likely to have small kidneys and progression to end-stage renal disease. VUR was common in the children with a UTI and who were ≤1 year of age. Clinicians should arrange ultrasound to diagnose urinary tract anomalies. Infants with urinary tract anomalies, neuropathic bladder and spina bifida should receive further voiding cystourethrography to diagnose VUR early, as this may help to prevent renal damage.

Development and Validation of a Scoring System for Assessment of Clinical Failure after Pediatric Robot-Assisted Laparoscopic Extravesical Ureteral Reimplantation: A Multi-Center Study

We aimed to develop and validate a scoring system as an objective assessment tool for predicting clinical failure after pediatric robotic extravesical ureteral reimplantation. Data for this multi-institutional retrospective cohort was obtained from two tertiary referral hospitals. We defined clinical failure as incomplete radiographic resolution or post-operative febrile UTI. Patients were stratified into low, intermediate, and high-risk groups according to the score. External validation was performed using the model projected to the external validation cohort. An amount of 115 renal units in the development cohort and 46 renal units in the validation cohort were analyzed. The prediction score was calculated with weighted points to each variable according to their regression coefficient as age (year) + BMI + BBD times 10 + VUR grade times 7 + console time (h) + hospital stay times 6. The C-index of our scoring system was 0.850 and 0.770 in the development and validation cohorts, respectively. Clinical failure was significantly different among risk groups: 0% (low-risk), 3.3% (intermediate-risk), and 22.2% (high-risk) (p = 0.004) in the development cohort. A novel scoring system using multiple pre- and intra-operative variables provides a prediction of children at risk of failure after robotic extravesical ureteral reimplantation.

Allograft Vesicoureteral Reflux after Kidney Transplantation

Allograft vesicoureteral reflux (VUR) is a leading urological complication of kidney transplantation. Despite the relatively high incidence, there is a lack of consensus regarding VUR risk factors, impact on renal function, and management. Dialysis vintage and atrophic bladder have been recognized as the most relevant recipient-related determinants of post-transplant VUR, whilst possible relationships with sex, age, and ureteral implantation technique remain debated. Clinical manifestations vary from an asymptomatic condition to persistent or recurrent urinary tract infections (UTIs). Voiding cystourethrography is widely accepted as the gold standard diagnostic modality, and the reflux is generally graded following the International Reflux Study Committee Scale. Long-term transplant outcomes of recipients with asymptomatic grade I-III VUR are yet to be clarified. On the contrary, available data suggest that symptomatic grade IV-V VUR may lead to progressive allograft dysfunction and premature transplant loss. Therapeutic options include watchful waiting, prolonged antibiotic suppression, sub-mucosal endoscopic injection of dextranomer/hyaluronic acid copolymer at the site of the ureteral anastomosis, and surgery. Indication for specific treatments depends on recipient’s characteristics (age, frailty, compliance with antibiotics), renal function (serum creatinine concentration < 2.5 vs. ≥ 2.5 mg/dL), severity of UTIs, and VUR grading (grade I-III vs. IV-V). Current evidence supporting surgical referral over more conservative strategies is weak. Therefore, a tailored approach should be preferred. Properly designed studies, with adequate sample size and follow-up, are warranted to clarify those unresolved issues.

Multifarious applications of bioactive glasses in soft tissue engineering

Tissue engineering (TE), a new paradigm in regenerative medicine, repairs and restores the diseased or damaged tissues and eliminates drawbacks associated with autografts and allografts. In this context, many biomaterials have been developed for regenerating tissues and are considered revolutionary in TE due to their flexibility, biocompatibility, and biodegradability. One such well-documented biomaterial is bioactive glasses (BGs), known for their osteoconductive and osteogenic potential and their abundant orthopedic and dental clinical applications. However, in the last few decades, the soft tissue regenerative potential of BGs has demonstrated great promise. Therefore, this review comprehensively covers the biological application of BGs in the repair and regeneration of tissues outside the skeleton system. BGs promote neovascularization, which is crucial to encourage host tissue integration with the implanted construct, making them suitable biomaterial scaffolds for TE. Moreover, they heal acute and chronic wounds and also have been reported to restore the injured superficial intestinal mucosa, aiding in gastroduodenal regeneration. In addition, BGs promote regeneration of the tissues with minimal renewal capacity like the heart and lungs. Besides, the peripheral nerve and musculoskeletal reparative properties of BGs are also reported. These results show promising soft tissue regenerative potential of BGs under preclinical settings without posing significant adverse effects. Albeit, there is limited bench-to-bedside clinical translation of elucidative research on BGs as they require rigorous pharmacological evaluations using standardized animal models for assessing biomolecular downstream pathways.

A genome‑wide scan to locate regions associated with familial vesicoureteral reflux

Vesicoureteral reflux (VUR) is a congenital malformation carrying a high risk of recurrent urinary tract infections (UTI) and, at worst, chronic renal failure. Familial clustering implies a genetic etiology, but studies during the past few decades have demonstrated a causal gene variant in <10% of patients with VUR. The aim of the present study was to search for fully or partially shared ancestral haplotypes in 14 families from south-western Sweden with at least three affected members. High-density single nucleotide polymorphism microarray was used for genotyping prior to analysis with a compatibility matching method developed in-house, and the analysis of copy number variations (CNV). No single unique haplotype was revealed to be shared by the families, thereby excluding a common ancestry and founder mutations as a probable cause of VUR. After evaluation of haplotypes shared by subsets of families, a haplotype shared by nine families was found to be of particular interest. This haplotype, located at chromosomal region 4q21.21, harbours two tentative candidate genes (bone morphogenetic protein 3 and fibroblast growth factor 5), both expressed in metanephros and with known functions during nephrogenesis. As to CNV, only one family had a specific CNV shared by all affected members. This was a focal deletion at 5q31.1 including follistatin-like 4, a gene without a previous known connection to VUR. These data demonstrated the genetic heterogeneity of VUR and indicated that an interaction of environmental and genetic factors, including non-coding and epigenetic regulators, all contribute to the complexity of VUR.

The First Thousand Days: Kidney Health and Beyond

The global burden of chronic kidney disease (CKD) is rising. A superior strategy to advance global kidney health is required to prevent and treat CKD early. Kidney development can be impacted during the first 1000 days of life by numerous factors, including malnutrition, maternal illness, exposure to chemicals, substance abuse, medication use, infection, and exogenous stress. In the current review, we summarize environmental risk factors reported thus far in clinical and experimental studies relating to the programming of kidney disease, and systematize the knowledge on common mechanisms underlying renal programming. The aim of this review is to discuss the primary and secondary prevention actions for enhancing kidney health from pregnancy to age 2. The final task is to address the potential interventions to target renal programming through updating animal studies. Together, we can enhance the future of global kidney health in the first 1000 days of life.

Molecular Screening of PAX2 Gene Polymorphism in Primary Vesicoureteral Reflux Patients in Taif Governorate, KSA

&lt;b&gt;Background and Objective:&lt;/b&gt; Primary Nonsyndromic Vesicoureteral Reflux (PVUR) is a widespread genetic malformation and considered a prevalent Congenital Abnormality of the Kidney and Urinary Tract (CAKUT). Mutations in the &lt;i&gt;PAX2 &lt;/i&gt;gene have been associated with abnormalities in the kidney extending from CAKUT to oncogenic processes. The present study analyzes the &lt;i&gt;PAX2&lt;/i&gt; polymorphisms and their association with primary VUR in Saudi children patients from the Taif governorate. &lt;b&gt;Materials and Methods:&lt;/b&gt; Fifteen children with primary VUR were identified and screened for gene mutations in the &lt;i&gt;PAX2&lt;/i&gt; gene by direct sequencing method of purified Polymerase Chain Reaction (PCR) products of all exons to elucidate the correlation between &lt;i&gt;PAX2&lt;/i&gt; gene and VUR. &lt;b&gt;Results:&lt;/b&gt; Seven new variants have been defined. Three polymorphic missense variants in homozygous genotype form were found in intron 8 and detected in eight patients, One missense mutation was found in exon 10 in the site of transactivation domain and detected in ten patients and &lt;i&gt;in-silico&lt;/i&gt; analysis predicted it as a pathogenic one, Three mutations were found in exon 11 and detected in all patients as a compound homozygous. &lt;b&gt;Conclusion:&lt;/b&gt; &lt;i&gt;PAX2&lt;/i&gt;is important for normal kidney development and mutations in the gene possibly lead to disturbance in the protein structure and could be non-functional thus mutations in &lt;i&gt;PAX2&lt;/i&gt; may be one of the causes of PVUR in Saudi Arabia. Further investigation is necessary to understand the aetiology of disease and maybe other genes implicated in VUR.

Asian guidelines for urinary tract infection in children

The followings are the level of evidence (LE) and grade of recommendation (GR) on pediatric UTI in Asia. Classification according to the sites of infection (lower versus upper tract), the number of episode (first versus recurrent), the severity (simple versus severe), or the existence of complicating factor (uncomplicated versus complicated) is useful to differentiate children with UTI whether they are at risk of renal damage or not (LE: 2, GR: B). Diagnosis of UTI requires both urinalysis that suggests infection and positive urine culture (LE:3, GR B). For pre-toilet trained children, urine specimen for culture should be collected by urethral catheterization or suprapubic aspiration. For toilet trained children, midstream clean catch urine is reliable (LE: 3, GR: A). Urine culture is considered positive if it demonstrates growth of a single bacterium with the following colony counts: (1) any growth by suprapubic aspiration, (2) >5 × 104 CFU/ml by urethral catheterization, or (3) >105 CFU/ml by midstream clean catch (LE:3, GR: B). For children with febrile UTI, renal and bladder ultrasonography (RBUS) should be routinely performed as soon as possible (LE: 3, GR: C). RBUS should be followed up 6 months later in children with acute pyelonephritis and/or VUR (LE: 3, GR: C). Acute DMSA scan can be performed when severe acute pyelonephritis or congenital hypodysplasia is noted on RBUS or when the diagnosis of UTI is in doubt by the clinical presentation (LE: 3, GR: C). Late DMSA scan (>6 months after the febrile UTI) can be performed in children with severe acute pyelonephritis, high-grade VUR, recurrent febrile UTIs, or abnormal renal parenchyma on the follow-up RBUS (LE: 3, GR: C). Top-down or bottom-up approach for febrile UTI is suggested for the diagnosis of VUR. For top-down approach, VCUG should not be performed routinely for children after the first febrile UTI. VCUG is indicated when abnormalities are apparent on either RBUS or DMSA scan or both (LE: 2, GR: B). VCUG is also suggested after a repeat febrile UTI (LE:2, GR: B). Appropriate antibiotic should be given immediately after urine specimen for culture has been obtained (LE:2, GR: A). Initiating therapy with oral or parenteral antibiotics is equally efficacious for children (>3 months) with uncomplicated UTI (LE: 2: GR: A). The choice of empirical antibiotic agents is guided by the expected pathogen and the local resistance patterns (LE: 2, GR: A). For children with febrile UTI, the total course of antibiotic therapy should be 7-14 days (LE: 2, GR: B). Circumcision may, but not definitively, reduce the risk of febrile UTI in males and breakthrough febrile UTI in males with VUR. Circumcision should be offered to uncircumcised boys with febrile UTI and VUR in countries where circumcision is accepted by the general population (LE: 3, GR: B), while in countries where childhood circumcision is rarely performed, other measures for febrile UTI/VUR should be the preferred choice (LE: 4, GR: C). Bladder bowel dysfunction (BBD) is one of the key factors of progression of renal scarring (LE: 2). Early recognition and management of BBD are important in prevention of UTI recurrence (LE:2, GR: A). Antibiotic prophylaxis to prevent recurrent febrile UTI is indicated in children with moderate to high grade (III-V) VUR (LE: 1b, GR: A). Surgical intervention may be used to treat VUR in the setting of recurrent febrile UTI because it has been shown to decrease the incidence of recurrent pyelonephritis (LE: 2, GR: B).

Radiation exposure to infants undergoing voiding cystourethrography: The importance of the digital imaging technology

PURPOSE

To determine the radiation burden to infants undergoing voiding cystourethrography (VCUG) in a single institution and investigate the effect of shifting from analogue to digital imaging that allowed the use of a radiography-free examination protocol.

METHODS

Anthropometric and exposure data were prospectively collected for 35 consecutive infants undergoing VCUG on a digital system with a standardized examination protocol not including radiographs. Thermoluminescent dosimeters were used to determine entrance-skin dose. Monte Carlo simulations and patient-specific anthropomorphic phantoms were employed to determine organ/tissue doses and effective dose (ED). The associated theoretical risk of radiation-induced cancer was determined and compared to the nominal risk of cancer induction. The radiation burden from VCUG on a modern digital system with a contemporary examination protocol was compared to corresponding data reported previously for an analogue system in the same institution.

RESULTS

The median ED from VCUG was found 47 μSv. The associated total life attributable risk of radiation-induced cancer was found 10x10^-6 and 13x10^-6 for boys and girls, respectively. VCUG was found to increase the nominal risk of cancer by a factor of 1.000025 in boys and 1.000034 in girls. Shifting from analogue to digital imaging system resulted in 89% reduction of the radiation burden from VCUG.

CONCLUSION

The theoretical radiation risks for infants undergoing VCUG using a modern digital imaging system and a radiography-free protocol were found to be minor. The transition from analogue to digital equipment resulted in considerable reduction of the radiation burden from VCUG.

Is endothelial glycocalyx damage a cause of renal scarring in vesicoureteral reflux with febrile urinary tract infection?

INTRODUCTION

Endothelial glycocalyx is a luminal layer which can be damaged by inflammatory agents or pathogens. The endothelial glycocalyx damage is thought to have a role in the formation of renal scars in children who have febrile urinary tract infection and vesicoureteral reflux. This study aimed to compare the blood levels of endothelial glycocalyx components heparan sulfate and Syndecan-1 in children with and without renal scarring due to vesicoureteral reflux-associated febrile urinary tract infection.

MATERIALS AND METHODS

Data of the patients diagnosed with vesicoureteral reflux without renal scarring (Group 1), patients with vesicoureteral reflux and renal scarring (Group 2), and completely healthy children (Group 3) were retrospectively reviewed. Blood levels of heparan sulfate and Syndecan-1 were measured and the results were compared.

RESULTS

The entire cohort consisted of 90 patients; there were 30 patients in each group. Mean patient age was 49.7±18.0 months. Mean serum heparan sulfate (42.90±18.90 ng/mL) and Syndecan-1 (37.59±13.77 ng/mL) levels of Group 2 were significantly higher than those of other groups. The cut-off value for heparan sulfate was 35.17 ng/mL, with a 63% sensitivity and 86% specificity. The cut-off value for Syndecan-1 was 29.99 ng/mL with a 70% sensitivity and 80% specificity.

CONCLUSION

Our findings indicate that blood levels of heparan sulfate and Syndecan-1 could be related with renal scarring in patients with vesicoureteral reflux, especially in the setting of febrile urinary tract infection. However, due to their low sensitivity, these biomarkers should be used along with clinical data.

Copy Number Variant Analysis and Genome-wide Association Study Identify Loci with Large Effect for Vesicoureteral Reflux

BACKGROUND

Vesicoureteral reflux (VUR) is a common, familial genitourinary disorder, and a major cause of pediatric urinary tract infection (UTI) and kidney failure. The genetic basis of VUR is not well understood.

METHODS

A diagnostic analysis sought rare, pathogenic copy number variant (CNV) disorders among 1737 patients with VUR. A GWAS was performed in 1395 patients and 5366 controls, of European ancestry.

RESULTS

Altogether, 3% of VUR patients harbored an undiagnosed rare CNV disorder, such as the 1q21.1, 16p11.2, 22q11.21, and triple X syndromes ((OR, 3.12; 95% CI, 2.10 to 4.54; P=6.35×10-8) The GWAS identified three study-wide significant and five suggestive loci with large effects (ORs, 1.41-6.9), containing canonical developmental genes expressed in the developing urinary tract (WDPCP, OTX1, BMP5, VANGL1, and WNT5A). In particular, 3.3% of VUR patients were homozygous for an intronic variant in WDPCP (rs13013890; OR, 3.65; 95% CI, 2.39 to 5.56; P=1.86×10-9). This locus was associated with multiple genitourinary phenotypes in the UK Biobank and eMERGE studies. Analysis of Wnt5a mutant mice confirmed the role of Wnt5a signaling in bladder and ureteric morphogenesis.

CONCLUSIONS

These data demonstrate the genetic heterogeneity of VUR. Altogether, 6% of patients with VUR harbored a rare CNV or a common variant genotype conferring an OR >3. Identification of these genetic risk factors has multiple implications for clinical care and for analysis of outcomes in VUR.

Evaluation of the Diagnostic Value of Contrast-Enhanced Voiding Urosonography with Regard to the Further Therapy Regime and Patient Outcome-A Single-Center Experience in an Interdisciplinary Uroradiological Setting

Background and Objectives: Vesicoureteral reflux (VUR) describes a common pediatric anomaly in pediatric urology with a prevalence of 1-2%. In diagnostics, in addition to the gold standard of voiding cystourethrography (VCUG), contrast-enhanced urosonography (ceVUS) offers a radiation-free procedure, which, despite its advantages, is not yet widely used. In the present single-center study, subsequent therapeutic procedures and outcomes after ceVUS of 49 patients were investigated. The aim of the study is to investigate the efficacy of ceVUS with the intention of broader clinical implementation. Materials and Methods: Between 2016 and 2020, 49 patients were retrospectively included and received a ceVUS to evaluate VUR. With a distribution of 47:2 (95.9%), a clear female predominance was present. The age of the patients varied between 5 months and 60 years at the time of ceVUS. All examinations were all performed and subsequently interpreted by a single experienced radiologist (EFSUMB level 3). Results: Compared to intraoperative findings, ceVUS shows a sensitivity of 95.7% with a specificity of 100%. Allergic reactions to the contrast medium could not be observed. Conclusion: With its high sensitivity and intraoperative validation, ceVUS offers an excellent alternative to VCUG, the gold standard in the diagnosis of VUR. In addition, ceVUS is a radiation-free examination method with a low risk profile that offers an exceptional diagnostic tool in the diagnostic clarification of recurrent urinary tract infections with the suspected diagnosis of VUR and should also be included in the consideration of a diagnosis next to the established VCUG, especially in younger children.

The ABCs of Voiding Cystourethrography

Voiding cystourethrography (VCUG) demonstrates the anatomy of the urinary system and is used to detect the presence/absence of vesicoureteral reflux. It is the most important modality for urological fluoroscopic examination in children. For improved patient care, it is important to understand and perform VCUG appropriately. Therefore, an in-depth review of VCUG protocols and techniques has been presented herein. In addition, tips, tricks, and pitfalls associated with the technique have also been addressed.

Symptomatology and Clinic of Hydronephrosis Associated With Uretero Pelvic Junction Anomalies

The most common cause of hydronephrosis in the pediatric age group is ureteropelvic junction-type hydronephrosis (UPJHN). Since the advent of widespread maternal ultrasound screening, clinical presentation of hydronephrosis associated with UPJ anomalies has changed dramatically. Today most cases are diagnosed in the prenatal period, and neonates present without signs or symptoms. For those who are not detected at birth, UPJHN eventually presents throughout childhood and even adulthood with various symptoms. Clinical picture of UPJHN highly depends on the presence and severity of obstruction, and whether it affects single or both kidneys. Abdominal or flank pain, abdominal mass, hematuria, kidney stones, urinary tract infections (UTI), and gastrointestinal discomfort are the main symptoms of UPJHN in childhood. Other less common findings in such patients are growth retardation, anemia, and hypertension. UTI is a relatively rare condition in UPJHN cases, but it may occur as pyelonephritis. Vesicoureteric reflux should be kept in mind as a concomitant pathology in pediatric UPJHN that develop febrile UTI. Although many UPJHN cases are known to improve over time, close clinical observation is critical in order to avoid irreversible kidney damage. The most appropriate approach is to follow-up the patients considering the presence of symptoms, the severity of hydronephrosis and the decrease in kidney function and, if necessary, to decide on early surgical intervention.

Voiding cystourethrography and 99MTC-MAG3 renal scintigraphy in pediatric vesicoureteral reflux: what is the role of indirect cystography?

BACKGROUND

Primary vesicoureteral reflux (VUR) is the most common urological anomaly in children. Voiding cystourethrography (VCUG) is considered the reference standard for the diagnosis of VUR. Even if it is a secure and standardized technique, it is still an invasive method, hence, the effort to find an alternative method to diagnose VUR. The aim of the study is to evaluate the diagnostic accuracy of ^99mTC-MAG3 scintigraphy with indirect cystography in detecting VUR and to estimate any interobserver variability in ^99mTC-MAG3 scintigraphy interpretation.

METHODS

The authors retrospectively reviewed all the pediatric patients who underwent both a VCUG and a ^99mTC-MAG3 renal scintigraphy at the study institution between 2012 and 2016.

RESULTS

A total of 86 children (and 168 renal units) were included. MAG3 scan revealed a sensitivity of 54% and a specificity of 90% with positive predictive value of 79% and negative predictive value of 73%. Each MAG3 scintigraphy was then independently and blindly evaluated by a pediatric urologist and two nuclear physicians. After revision, the concordance between VCUG and MAG3 in reflux cases dropped from 54% to 27% (on average), and the reviewers reclassified most examinations as non-conclusive.

CONCLUSIONS

^99mTC-MAG3 renal scintigraphy with indirect cystography showed low sensitivity in detecting VUR of any grade and cannot, therefore, be proposed as completely alternative to VCUG in the diagnosis of VUR. Moreover, MAG3 scintigraphy interpretation for the diagnosis of VUR has a very high interobserver variability, mostly because of the lack of a correct and complete voiding phase.

DNA copy number variations in children with vesicoureteral reflux and urinary tract infections

Vesicoureteral reflux (VUR) is a complex, heritable disorder. Genome-wide linkage analyses of families affected by VUR have revealed multiple genomic loci linked to VUR. These loci normally harbor a number of genes whose biologically functional variant is yet to be identified. DNA copy number variations (CNVs) have not been extensively studied at high resolution in VUR patients. In this study, we performed array comparative genomic hybridization (aCGH) on a cohort of patients with a history of both VUR and urinary tract infection (UTI) with the objective of identifying genetic variations responsible for VUR and/or UTI susceptibility. UTI/VUR-associated CNVs were identified by aCGH results from the 192 Randomized Intervention for Children With Vesicoureteral Reflux (RIVUR) patients compared to 683 controls. Rare, large CNVs that are likely pathogenic and lead to VUR development were identified using stringent analysis criteria. Because UTI is a common affliction with multiple risk factors, we utilized standard analysis to identify potential disease-modifying CNVs that can contribute to UTI risk. Gene ontology analysis identified that CNVs in innate immunity and development genes were enriched in RIVUR patients. CNVs affecting innate immune genes may contribute to UTI susceptibility in VUR patients and may provide the first step in assisting clinical medicine in determining adverse outcome risk in children with VUR.

Widening the lens to childhood: relevance and lifetime risk of kidney failure

PURPOSE OF REVIEW

Lifetime risk of outcomes is emerging as a highly relevant health indicator, even in the context of low absolute risk of disease progression in short time frames. Evidence to support this concept for kidney failure is increasing, with growing emphasis on the long-term impact of risk factors occurring early in life.

RECENT FINDINGS

Proteinuria and stage of chronic kidney disease (CKD) are now established predictors of CKD progression in children, and youth with type 2 diabetes are emerging as a group at significant risk. Recent population-based studies have also examined the lifetime risk of end-stage renal disease in individuals with any childhood CKD. A recent study found that even in the absence of biomarkers of renal injury, childhood CKD can increase the lifetime risk of end-stage renal disease four-fold, and up to 10-fold in adults less than 40 years of age.

SUMMARY

Children with CKD are at high lifetime risk of kidney failure and require follow-up. Identifying children at highest lifetime risk through the use of biomarkers and risk equations, and determining the optimal duration and intensity of follow-up requires further research.

Urinary excretion of pentraxin-3 correlates with the presence of renal scar following acute pyelonephritis in children

PURPOSE

Acute pyelonephritis is associated with considerable morbidity and potential for renal scarring. Pentraxin3 (PTX3) is a recently discovered mediator of inflammation. The objective of this study was to investigate the changes in serum and urine PTX3 levels in children who had a history of pyelonephritis and were diagnosed with renal parenchymal scar (RPS) and/or vesicoureteral reflux (VUR).

METHODS

The study included 88 children (31 males, 57 females) aged between 3 months and 18 years. The children included in the study were divided into four groups: VUR with RPS (Group 1), RPS without VUR (Group 2), VUR without RPS (Group 3), and healthy children without a history of hydronephrosis or UTI history (Group 4). After the initial evaluation, the participants were further divided into two more groups and re-evaluated: Children with RPS (Group 1 + 2), children without RPS (Group 3 + 4), children with VUR (Group 1 + 3), and children without VUR (Group 2 + 4).

RESULTS

We found that urine pentraxin 3 (uPTX3) and uPTX3/Creatinine levels were significantly higher in the groups with renal scar with or without VUR than the ones without RPS [mean uPTX3, 3.5 pg/ml (min-max 0.0022-12.3668) vs. 2.2 pg/ml (min-max 0.0022-18.5868) and uPTX3/creatinine, 10.5 pg/mg (min-max 0.0035-51.1) vs. 5.8 pg/mg (min-max 0.0004-78.7), p < 0.01]. uPTX3 levels were not different among the groups with and without VUR. In addition, serum PTX3 levels were not different among the groups.

CONCLUSIONS

We showed that urinary PTX3 increased only in patients with scarred kidneys. These results might be helpful to predict RPS due to past pyelonephritis.

Congenital Disorders of the Human Urinary Tract: Recent Insights From Genetic and Molecular Studies

The urinary tract comprises the renal pelvis, the ureter, the urinary bladder, and the urethra. The tract acts as a functional unit, first propelling urine from the kidney to the bladder, then storing it at low pressure inside the bladder which intermittently and completely voids urine through the urethra. Congenital diseases of these structures can lead to a range of diseases sometimes associated with fetal losses or kidney failure in childhood and later in life. In some of these disorders, parts of the urinary tract are severely malformed. In other cases, the organs appear grossly intact yet they have functional deficits that compromise health. Human studies are beginning to indicate monogenic causes for some of these diseases. Here, the implicated genes can encode smooth muscle, neural or urothelial molecules, or transcription factors that regulate their expression. Furthermore, certain animal models are informative about how such molecules control the development and functional differentiation of the urinary tract. In future, novel therapies, including those based on gene transfer and stem cell technologies, may be used to treat these diseases to complement conventional pharmacological and surgical clinical therapies.

Developmental pathology of congenital kidney and urinary tract anomalies

Congenital anomalies of the kidneys or lower urinary tract (CAKUT) are the most common causes of renal failure in children and account for 25% of end-stage renal disease in adults. The spectrum of anomalies includes renal agenesis; hypoplasia; dysplasia; supernumerary, ectopic or fused kidneys; duplication; ureteropelvic junction obstruction; primary megaureter or ureterovesical junction obstruction; vesicoureteral reflux; ureterocele; and posterior urethral valves. CAKUT originates from developmental defects and can occur in isolation or as part of other syndromes. In recent decades, along with better understanding of the pathological features of the human congenital urinary tract defects, researchers using animal models have provided valuable insights into the pathogenesis of these diseases. However, the genetic causes and etiology of many CAKUT cases remain unknown, presenting challenges in finding effective treatment. Here we provide an overview of the critical steps of normal development of the urinary system, followed by a description of the pathological features of major types of CAKUT with respect to developmental mechanisms of their etiology.

Hand-held, clinical dual mode ultrasound - photoacoustic imaging of rat urinary bladder and its applications

Urinary bladder imaging is critical to diagnose urinary tract disorders, and bladder cancer. There is a great need for safe, non-invasive, and sensitive imaging technique which enables bladder imaging. Photoacoustic imaging is a rapidly growing imaging technique for various biological applications. It can be combined with clinical ultrasound imaging system for hand-held, dual modal ultrasound-photoacoustic real-time imaging. Structural (bladder wall) and functional (accretion of nanoparticles) bladder imaging is shown here with combined ultrasound and photoacoustic imaging in rats. Photoacoustic images of bladder wall is shown using black ink as the contrast agent. Chicken tissues were stacked on the abdomen of the animal to demonstrate the feasibility of photoacoustic imaging till a depth of 2 cm. Also, the feasibility of photoacoustic imaging for a common bladder disorder, vesicoureteral reflux is studied using urinary tract mimicking phantom. It is also shown that a clinical ultrasound system can be used for photoacoustic imaging of non-invasive clearance study of gold nanorods from circulation by monitoring the gradual accumulation of the gold nanorods in the bladder. The time taken for accumulation of nanorods in the bladder can be used as an indicator of the clearance rate of the nanoparticle circulation from the body.

Endoscopic Injection of Dextranomer/Hyaluronic Acid as First Line Treatment in 851 Consecutive Children with High Grade Vesicoureteral Reflux: Efficacy and Long-Term Results

PURPOSE

Endoscopic injection of dextranomer/hyaluronic acid is widely acknowledged as first line treatment of lower grade vesicoureteral reflux. We demonstrate its long-term efficacy and safety in eradicating high grade reflux.

MATERIALS AND METHODS

A total of 518 girls and 333 boys with a median age of 2.3 years (range 2 months to 13.7 years) underwent endoscopic correction of high grade vesicoureteral reflux using dextranomer/hyaluronic acid. Reflux was unilateral in 415 cases and bilateral in 436, comprising 1,287 refluxing units. Reflux was grade IV in 1,153 ureters (89.6%) and grade V in 134 (10.4%). ^99mTechnetium-dimercaptosuccinic acid scintigraphy identified renal scarring in 317 patients (37.3%). Followup ultrasound and voiding cystourethrogram were performed 3 months after intervention and renal ultrasound yearly thereafter. Median followup was 8.5 years (range 6 months to 16 years).

RESULTS

Overall resolution rate after the first endoscopic injection was 69.5% (895 of 1,287 cases), with resolution in 70.4% of grade IV and 61.9% of grade V cases. Reflux resolved after a second injection in 259 cases (20.1%) and after a third injection in 133 (10.4%). Persistent reflux after initial treatment was significantly more common in patients younger than age 1 year and in individuals with renal scarring. No significant postoperative complications were observed and no patient required ureteral reimplantation. Following reflux resolution febrile urinary tract infection developed in 43 children (5.1%), including 24 (55.8%) during the first year, 15 (34.9%) during the second year and 4 (9.3%) during year 3 or later. Of these patients 6 had reflux recurrence and 8 had neocontralateral grade III reflux, which was successfully treated with a single endoscopic injection of dextranomer/hyaluronic acid.

CONCLUSIONS

Endoscopic injection of dextranomer/hyaluronic acid is an efficient and safe long-term treatment for grade IV and V vesicoureteral reflux, and can easily be repeated in patients with treatment failure with a high subsequent resolution rate.

Pregnancy outcomes after maternal use of thiocolchicoside: A case series

OBJECTIVE

The 2014 report by European Medicines Agency (EMA) restricted the use of thiocolchicoside for all reproductive-age women. In this study, we aim to expand the systematically-collected human data and discuss it within the frame provided by this report.

METHODS

We identified and evaluated the outcomes of 48 prospectively recorded pregnancies referred to Terafar (Teratology Information Service, Izmir, Turkey).

RESULTS

Of 42 pregnancies with first-trimester exposure and known outcomes, 31 resulted in live births, four in miscarriage and seven ended with elective terminations. There were 26 normal outcomes, two major and three minor congenital malformations among the live births.

CONCLUSIONS

Despite a number of limitations, our results and previous case series collectively strengthen the view that thiocolchicoside is unlikely to be a major teratogen. EMA's 2014 report should be revised to reflect this finding, while current restrictions on use should continue until more detailed safety information is available.

Genome-wide linkage and association study implicates the 10q26 region as a major genetic contributor to primary nonsyndromic vesicoureteric reflux

Vesicoureteric reflux (VUR) is the commonest urological anomaly in children. Despite treatment improvements, associated renal lesions – congenital dysplasia, acquired scarring or both – are a common cause of childhood hypertension and renal failure. Primary VUR is familial, with transmission rate and sibling risk both approaching 50%, and appears highly genetically heterogeneous. It is often associated with other developmental anomalies of the urinary tract, emphasising its etiology as a disorder of urogenital tract development. We conducted a genome-wide linkage and association study in three European populations to search for loci predisposing to VUR. Family-based association analysis of 1098 parent-affected-child trios and case/control association analysis of 1147 cases and 3789 controls did not reveal any compelling associations, but parametric linkage analysis of 460 families (1062 affected individuals) under a dominant model identified a single region, on 10q26, that showed strong linkage (HLOD = 4.90; ZLRLOD = 4.39) to VUR. The ~9Mb region contains 69 genes, including some good biological candidates. Resequencing this region in selected individuals did not clearly implicate any gene but FOXI2, FANK1 and GLRX3 remain candidates for further investigation. This, the largest genetic study of VUR to date, highlights the 10q26 region as a major genetic contributor to VUR in European populations.

Modulation of apoptotic response by LAR family phosphatases-cIAP1 signaling during urinary tract morphogenesis

The elimination of unwanted cells by apoptosis is necessary for tissue morphogenesis. However, the cellular control of morphogenetic apoptosis is poorly understood, notably the modulation of cell sensitivity to apoptotic stimuli. Ureter maturation, the process by which the ureter is displaced to the bladder wall, represents an exquisite example of morphogenetic apoptosis, requiring the receptor protein tyrosine phosphatases (RPTPs): LAR and RPTPσ. Here we show that LAR-RPTPs act through cellular inhibitor of apoptosis protein 1 (cIAP1) to modulate caspase 3,7-mediated ureter maturation. Pharmacologic or genetic inactivation of cIAP1 reverts the apoptotic deficit of LAR-RPTP-deficient embryos. Moreover, Birc2 (cIAP1) inactivation generates excessive apoptosis leading to vesicoureteral reflux in newborns, which underscores the importance of apoptotic modulation during urinary tract morphogenesis. We finally demonstrate that LAR-RPTP deficiency increases cIAP1 stability during apoptotic cell death. Together these results identify a mode of cIAP1 regulation playing a critical role in the cellular response to apoptotic pathway activation in the embryo.

Bilateral Hydroureteronephrosis with a Hypertrophied, Trabeculated Urinary Bladder

Bilateral hydroureteronephrosis involves the dilatation of the renal pelvis, calyces and ureter; it develops secondary to urinary tract obstruction and leads to a build-up of back pressure in the urinary tract, and it may lead to impairment of renal function and ultimately culminate in renal failure. Although clinically silent in most cases, it can be diagnosed as an incidental finding during evaluation of an unrelated cause. In a minority of patients, it presents with signs and symptoms. Renal calculus is the most common cause, but there are multiple non-calculus aetiologies, and they depend on age and sex. Pelviureteric junction obstruction, benign prostatic hypertrophy, urethral stricture, neurogenic bladder, retroperitoneal mass and bladder outlet obstruction are some of the frequent causes of hydroureteronephrosis in adults. The incidence of non-calculus hydronephrosis is more common in males than in females. Ultrasonography is the most important baseline investigation in the evaluation of patients with hydronephrosis. Here, we report a rarely seen case of bilateral hydroureteronephrosis associated with a hypertrophied, trabeculated bladder in an adult male cadaver, suspected to be due to a primary bladder neck obstruction, and analyse its various other causes, clinical presentations and outcomes.