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 hidden burden of Pediatric urology in Sub-Saharan Africa: an analysis of hospital admission data from three East African Health Centres.

Specialist facilities for children are still unavailable in some Sub-Saharan African contexts. It is the case of pediatric urology, whose recent advances are still largely unshared. Prenatal diagnosis of urinary abnormalities (CAKUT) is largely unknown. Early recognition and referral of Undescended testis (UDT), Hypospadia, bladder exstrophy epispadias complex, ambiguous genitalia, stone disease, and tumours are uncommon in rural areas. Missed diagnosis is not uncommon and delayed management is associated with poor outcomes. We present a cross-sectional, descriptive study about the epidemiology of Pediatric urological admissions to three sub-Saharan East African Hospitals. All the urological cases between 0-18 years referred to three distinct East African Hospitals over 124 weeks were considered. Prevalence of different groups of diseases, age, and mode of presentation were reported. We found 351 cases (M/F 127/24) out of 2543 surgical referrals (13%). Seventy percent of cases were Hypospadias and UDT. Fifty percent of UDT were beyond 6, and most Hypospadias were between 4 and 7 yrs. CAKUT had a very low prevalence (4.84%), and about 50% of Wilms Tumours came too late to be resectable. In many African contexts, urology is still a tiny portion of the pediatric surgical workload compared to the 25% of European and American reports. There are also differences in the epidemiology of genitourinary conditions. A hidden burden of diseases may be presumed, remaining undiagnosed due to the shortage of specialist facilities.

Longitudinal follow-up of bladder function in children who participated in the Swedish Reflux Trial.

BACKGROUND: Several publications have reported the coexistence of vesicoureteral reflux (VUR) and bladder dysfunction in children. Whether this dysfunction remains in the longer term is not yet known. OBJECTIVE: This study revisited children who participated in the Swedish Reflux Trial (SRT) with the primary aim of evaluating whether bladder and bowel dysfunction (BBD) in these patients persisted until adolescence. The secondary aim was to evaluate two BBD subgroups, and relations to recurrent urinary tract infections (UTI). STUDY DESIGN: Of the 161 eligible children at SRT study-end, 73 children participated. Their bladder function was evaluated longitudinally using a validated BBD questionnaire with symptom score (cut-off ≥7) and uroflowmetry, at five (T2) and ten years (T3) after study-end. T1 was the SRT study-end. Besides BBD, the sub-diagnoses overactive bladder (OAB) and dysfunctional voiding symptoms (DVS) were calculated from symptom scores. RESULTS: BBD was diagnosed in 37% of children at mean age 3.7 years, which decreased with age to 23% of adolescents (mean age 15.7). DVS and OAB subgroups were equally common at T1, but only DVS was identified at the last follow-up (T3) (p = 0.0008). Recurrent UTIs were seen in 17% at T3 and were more common in patients with BBD (p = 0.038). The gender distribution of BBD also changed, from being equally common at the end of the SRT to affecting mainly adolescent girls at the last follow-up (p = 0.022). Information was available regarding VUR status after repeat VCUGs during follow-up in 22 patients, 12 of them after endoscopic treatment. An improvement in VUR grade was found in the 22, but during follow-up numbers with BBD or UTI did not differ between treated and non-treated groups. DISCUSSION: The prevalence of BBD decreased from 37% at 3-4 years of age to 23% in adolescence, when it was almost exclusively seen in girls. BBD and the subgroup DVS were associated with UTI. Even if epidemiological studies have established a predisposition to bladder symptoms and UTI in girls, little is known about bladder function in adolescents with a history of VUR during the first years of life. One limitation of the study was the number of patients participating. Also, the number of patients with kidney damage was more common in the cohort. CONCLUSION: In this longitudinal follow-up of BBD in children with VUR, the number of children with BBD decreased with age. In adolescence, both BBD and recurrent UTIs mainly affected girls.

Vesicoureteral reflux is associated with increased risk of chronic kidney disease: A nationwide cohort study.

The association between vesicoureteral reflux (VUR) and chronic kidney disease (CKD) risk remains unestablished. We investigated the incidence of CKD in children with VUR in Taiwan and evaluated whether they had a higher risk of CKD than the general population. A nationwide population-based cohort study was conducted among children with VUR identified using Taiwan's National Health Insurance Research Database from 2000 to 2013. VUR was defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification codes. We identified the children with VUR and randomly selected comparison children according to a 1:1 ratio, matching them by age, gender, index year and comorbidity using data from the National Health Insurance Research Database. In total, 8648 children with VUR and 8648 comparison children were included. All children were followed from the study date until a diagnosis of CKD, termination of insurance, or the end of 2013. Cox proportional hazards regressions were performed to compare the hazard ratios for CKD between the 2 cohorts. Incident cases of CKD were identified. After adjustment for potential confounders, the study cohort was independently associated with a higher risk of CKD (adjusted hazard ratio, 3.78; 95% confidence interval, 2.10-7.18). This population-based cohort study indicated that children with VUR have a higher risk of CKD than those without VUR.

National Trends in Voiding Cystourethrograms During Hospitalization for Young Infants With Urinary Tract Infections.

OBJECTIVES: The American Academy of Pediatrics published a guideline in 2011 recommending against the routine use of voiding cystourethrogram (VCUG) in infants aged 2 to 24 months with first febrile urinary tract infection (UTI); however, the rates of VCUG for infants aged <2 months are unknown. The objective of this study was to determine the trend in VCUG performance during index hospitalization among infants aged 0 to 2 months with UTI. METHODS: This retrospective cohort study included infants aged birth to 2 months hospitalized with a UTI from 2008 to 2019 across 38 institutions in the Pediatric Health Information System. Outcome measures included recurrent UTI within 1 year, vesicoureteral reflux diagnosis within 1 year and antiurinary reflux procedure performed within 2 years. Trends over time were compared between preguideline (2008-2011) and postguideline periods (2012-2019) using piecewise mixed-effects logistic regression. RESULTS: The odds of VCUG decreased by 21% per year in the preguideline period (adjusted odds ratio, 0.79; 95% confidence interval, 0.77-0.81; P < .001) versus 20% (adjusted odds ratio, 0.80; 95% confidence interval, 0.77-0.83; P < .001) in the postguideline period. The preguideline and postguideline difference was not statistically significant (P = .60). There was no difference in the postguideline odds of UTI within 1 year (P = .07), whereas the odds of vesicoureteral reflux diagnosis (P < .001) and antiurinary reflux procedure performance (P < .001) decreased. CONCLUSIONS: VCUG performance during hospitalization has declined over the past decade among young infants hospitalized with UTI. Further work is needed to determine the optimal approach to imaging in these young infants.

Vesico-ureteric reflux in children and young people undergoing kidney transplantation.

Vesico-ureteric reflux (VUR) into transplanted kidneys in children and young people is a common occurrence, found in 19 to 60% of those who had an anti-reflux procedure and up to 79% in the absence of such a procedure. While VUR is unlikely to be of concern without evidence of symptomatic urinary tract infections, less certainty exists regarding outcomes when the VUR is associated with urinary tract infection (UTI) and transplant pyelonephritis. Issues explored will include additional risk factors that might predispose to UTI, any effect of pyelonephritis on acute and long-term kidney allograft function and practical strategies that may reduce the prevalence of infection.

Congenital malformations of the urinary tract: progression to chronic renal disease. / Malformaciones congénitas del tracto urinario (CAKUT): evolución a enfermedad renal crónica.

INTRODUCTION: Congenital nephrourological abnormalities (CAKUT) are a particularly relevant group of diseases due to their high prevalence and the fact they are the main cause of chronic renal disease (CRD) in the pediatric population. Our objective was to determine the characteristics and prevalence of CAKUT in our setting, while identifying the factors associated with the occurrence of renal damage. MATERIALS AND METHODS: A retrospective, descriptive, analytical, cross-sectional study of patients seen in the Pediatric Nephrology Department of a third-level hospital from January 1 to December 31, 2018 was carried out. Epidemiological, clinical, and analytical variables were assessed, and potential risk factors associated with CRD were searched for. RESULTS: The study involved 685 patients with 827 kidney units affected by CAKUT with a mean age of 9.98 ± 5.12 years. 62.2% were male, and the mean follow-up period after diagnosis was 9.95 ± 5.09 years. 58.8% were non-obstructive dilations, followed by renal dysplasia, obstructive dilations, and number and position abnormalities. The most frequent malformation was vesicoureteral reflux (VUR). The most commonly affected side was the left (47.5%). 55% of the diagnoses were prenatal. 172 patients underwent surgery. The initially chosen treatment for VUR was endourological. Overall re-intervention rate was 20%. Of the total number of patients, glomerular filtration rate was analyzed in 383, 95 (24.8%) of whom had CRD (86% in stage 2). Male sex, bilaterality, and proteinuria were risk factors associated with CRD. CONCLUSIONS: Knowledge of the epidemiological and clinical characteristics of children with CAKUT and the factors associated with CRD helps to individualize the clinical follow-up of these patients, thus customizing diagnostic tests and healthcare resources.

INTRODUCCION: Las anomalías nefrourológicas congénitas (CAKUT), constituyen un grupo de enfermedades de gran relevancia por su alta prevalencia y por ser la principal causa de enfermedad renal crónica (ERC) en la población pediátrica. Nuestro objetivo es conocer las características y la prevalencia de CAKUT en nuestro medio, identificando los factores asociados a la aparición de daño renal. MATERIAL Y METODOS: Estudio retrospectivo, descriptivo, analítico y transversal, que incluyó los pacientes atendidos en la consulta de Nefrología Pediátrica de un hospital de tercer nivel desde el 1 de enero al 31 de diciembre de 2018. Se analizaron variables epidemiológicas, clínicas y analíticas, y se buscaron posibles factores de riesgo asociados a ERC. RESULTADOS: Se incluyeron 685 pacientes con 827 unidades renales con CAKUT con una edad media de 9,98 ± 5,12 años. El 62,2% fueron varones y el seguimiento medio desde el diagnóstico fue de 9,95 ± 5,09 años. El 58,8% fueron dilataciones no obstructivas, seguido por displasia renal, dilataciones obstructivas y anomalías de número y posición. La malformación más frecuente fue el reflujo vesicoureteral (RVU). El lado más afectado fue el izquierdo (47,5%). El 55% de los diagnósticos fueron prenatales. Fueron intervenidos 172 pacientes. El tratamiento inicial de elección en el RVU fue endourológico. La tasa de reintervención global alcanzó el 20%. Del total de pacientes, se pudo analizar el filtrado glomerular en 383 pacientes, de los cuales 95 (24,8%) tenían ERC (86% en estadio 2). El sexo masculino, la bilateralidad y la proteinuria fueron factores de riesgo asociados a la ERC. CONCLUSIONES: El conocimiento de las características epidemiológicas y clínicas de los niños con CAKUT y de los factores asociados a la ERC ayuda a individualizar el seguimiento clínico de estos pacientes adecuando las pruebas diagnósticas y los recursos sanitarios.

Incidence and resolution of de novo hydronephrosis after pediatric robot-assisted laparoscopic extravesical ureteral reimplantation for primary vesicoureteral reflux.

INTRODUCTION: With the advent of robot-assisted laparoscopic ureteral reimplantation (RALUR) for primary vesicoureteral reflux (VUR), understanding and minimizing its complications continues to be critical. Incidence of de novo hydronephrosis after RALUR could be indicative of an outcome that needs further study or could be a benign transient finding. OBJECTIVE: In the present study, we hypothesized that the incidence of de novo hydronephrosis after RALUR is low and resolves spontaneously. METHODS: An IRB-approved prospective single-institutional registry was utilized to identify all patients undergoing RALUR via an extravesical approach from 2012 to 2020. Patients with primary VUR and minimal (Grade I SFU) or no hydronephrosis prior to surgery were included. Patients who had other associated pathology or underwent concomitant procedures were excluded. Preoperative characteristics including VUR and hydronephrosis grades as well as post-operative clinical details and hydronephrosis grades were aggregated and analyzed. RESULTS: 86/172 (50%) patients (133 ureters), with median reflux grade of 3 (IQR: G2, G3) met the inclusion criteria. Patients underwent RALUR at a median age of 5.7 years (IQR: 3.4, 8.7) with median 36.2 months (IQR: 19.6, 63.6) follow-up. Renal ultrasound at 4-6 weeks post-op showed de novo hydronephrosis in 18 (13.5%) ureters; the complete resolution was seen in 13 ureters (72%) at a median of 4.5 months from surgery. Among the 5 with non-resolved hydronephrosis (SFU G2:4, G3:1), 2 patients (3 ureters) underwent subsequent interventions. DISCUSSION: The present study evaluating the natural history of de novo hydronephrosis after RALUR-EV performed for primary VUR, is to our knowledge the largest cohort of patients undergoing RALUR that this has been studied in. In our cohort, the incidence of de novo hydronephrosis after RALUR was 13.5%, similar to rates reported in two OUR cohorts, and significantly lower than reported incidence rates of 22-26% in several OUR cohorts, and 30% in a RALUR cohort. In the present cohort, hydronephrosis resolved spontaneously in more than 72% of cases. The median time from surgery until resolution of hydronephrosis was 4.5 (1.6, 10.5) months, which is shorter in comparison to the average time to resolution of 7.6 months, reported by Kim et al. in an earlier study. CONCLUSIONS: De novo hydronephrosis after RALUR can be followed with serial renal ultrasounds. The majority of de novo hydronephrosis post-RALUR is transient and resolves spontaneously within a year of surgery with a very low re-intervention rate.

The prevalence of familial vesicoureteric reflux in infants with normal antenatal scans.

AIM: To determine the prevalence of familial vesicoureteric reflux (VUR) by studying the outcomes of screening in a contemporary cohort of newborns with normal antenatal kidney scans. METHODS: A review of screening outcomes in newborns with a first degree relative with VUR, normal antenatal scans and no prior urine infections between 2014-2019 at three maternity units in the North East of England was conducted. Imaging consisted of micturating cystourethrogram (MCUG) in all and renal tract ultrasound scan (RUS) routinely in two units and by clinician preference in one unit. RESULTS: At a median age of 59 days, 265 infants underwent MCUG. High-grade VUR (Grades 3-5) was detected in 13 (4.9%) and low-grade VUR (Grades 1-2) in 24 (9.1%). In the 152 infants who had a RUS, abnormalities were detected in 21 (13.8%). An abnormal postnatal RUS has a low positive predictive value (14.3%) for high-grade VUR, but a normal RUS has a high negative predictive value (95.4%). CONCLUSION: Compared to historical cohorts from two decades ago, the yield from familial VUR screening is low and unjustifiable in the setting of normal antenatal anomaly scans.

Epidemiologic, microbiologic and imaging characteristics of urinary tract infections in hospitalized children < 2 years of age diagnosed with anatomic abnormalities of the urinary tract.

BACKGROUND: To compare the epidemiologic, microbiologic and imaging characteristics of urinary tract infections (UTI) in children <2 years of age with and without anatomic urinary tract abnormalities (AA). METHODS: All children hospitalized with UTI during 1.1.2005-31.12.2018 were included. The study group (patients with AA) included 76 patients. The control group (99 patients) included patients without AA. RESULTS: 1163 children were hospitalized. Age at diagnosis was younger in the study group vs. controls (5.2 ± 6.0 vs. 7.9 ± 7.5 months, P = 0.038). Uropathogens distribution was different (P = 0.007), with lower Escherichia coli (Ec) and Proteus mirabilis (Pm) percentages in the study group and higher percentages of Enterococcus spp. (Ent) in controls. In the study group, Ec nonsusceptibility rates to ampicillin, amoxicillin/clavulanic acid, cefazolin, cefuroxime, TMP/SMX and ceftriaxone were 58%, 40%, 14%, 14%, 12% and 10%, respectively, with no differences vs. controls. Ultrasound (US) was performed in 69/76 (98%) patients with AA (84.1%, abnormal); bilateral (39.7%) and unilateral (32.7%) ureteral dilatation were the most frequent findings. Voiding cystourethrography was performed in 46 patients (pathologic in 35, 76%); 31 (81.6%) patients had vesicoureteral reflux (VUR) (bilateral in 11, 35.5%; grade 4/5 in 7 patients). Uropathogens distribution in VUR patients differed between study and control groups, with lower Ec and Pm in the first group and higher Pseudomonas aeruginosa and Ent percentages in the control group. CONCLUSION: Age at diagnosis was lower and pathogen distribution was different in patients with AA. Antibiotic susceptibility patterns of the main uropathogens were similar between patients with or without AA.

Utility of renal scintigraphy in diagnosis of multicystic dysplastic kidney.

PURPOSE: To compare the prevalence of vesicoureteral reflux (VUR), febrile urinary tract infection (fUTI), and chronic kidney disease (CKD) among patients with multicystic dysplastic kidney (MCDK) diagnosed by renal scintigraphy (RS) versus follow-up renal ultrasound (RUS) alone. METHODS: This was a retrospective review of patients seen at a tertiary care center from 2010 to 2020 with MCDK diagnosed by RS or follow-up RUS. Differences in the prevalence of VUR, fUTI, and CKD by cohort were assessed using logistic regression analysis, Pearson X2 , and Fisher's Exact tests. Temporal trends in diagnostic methods used (RUS versus RUS + RS) were evaluated using the Cochran-Armitage trend test. RESULTS: One-hundred seventy-two patients were included: 50% (n = 86) underwent RUS + RS and 50% (n = 86) underwent RUS alone to diagnose MCDK. Prevalence of VUR, fUTI, and CKD did not significantly vary between groups. Among patients who had a VCUG, 4.4% had contralateral VUR (1.7% RUS + RS group; 7.4% RUS group; p = 0.19) and 14.5% had at least one fUTI (16.3% RUS + RS group; 12.8% RUS group; p = 0.52). Females were significantly more likely to have at least one fUTI (p = 0.04). Four patients (2.3%) developed CKD, all in the RUS + RS cohort (p = 0.12). Diagnosis of MCDK by RUS versus RUS + RS did not significantly vary over time (p = 0.17). CONCLUSION: Patients with unilateral MCDK confirmed by RS versus RUS alone do not significantly vary in the prevalence of VUR, fUTI, or CKD. Renal scintigraphy studies may not be necessary in unilateral MCDK diagnosis but continue to be used.

Prevalence of reflux nephropathy in Iranian children with solitary kidney: results of a multi-center study.

BACKGROUND: Given the importance of the function of the remnant kidney in children with unilateral renal agenesis and the significance of timely diagnosis and treatment of reflux nephropathy to prevent further damage to the remaining kidney, we aimed to determine the prevalence of reflux nephropathy in this subgroup of pediatric patients. METHODS: In general, 274 children referred to pediatric nephrologists in different parts of Iran were evaluated, of whom 199 had solitary kidney and were included in this cross-sectional study. The reasons for referral included urinary tract infection (UTI), abnormal renal ultrasonography, being symptomatic, and incidental screening. Demographic characteristics, including age and gender were recorded. History of UTI and presence of vesicoureteral reflux (VUR) were evaluated. RESULTS: Of the 274 children evaluated in this study with the mean age (SD) of 4.71 (4.24) years, 199 (72.6%) had solitary kidney. Among these, 118 (59.3%) were male and 81 (60.7%) were female, 21.1% had a history of UTI, and VUR was present in 23.1%. The most common cause of referral was abnormal renal ultrasonography (40.2%), followed by incidental screening (21.1%), being symptomatic (14.1%), and UTI (5.5%). In 116 children (58.3%), the right kidneys and in 83 (41.7%) the left kidneys were absent. Besides, 14.6% of the participants had consanguineous parents and 3% had a family history of solitary kidney. Upon DMSA scan, the single kidney was scarred in 13.1%, of which only 7.5% were associated with VUR. In addition, proteinuria and hematuria were observed in 6.5% and 1.5% of children, respectively. CONCLUSIONS: The prevalence of reflux nephropathy was 7.5% in children with solitary kidney with a male predominance. Given the relatively high prevalence of reflux nephropathy in these children, screening for VUR in the remnant kidney appears to be essential in this population.

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

INTRODUCTION: Primary vesicoureteral reflux (VUR) is associated with urinary tract infections (UTIs) and renal damage. However, the importance of early diagnosis of VUR has been questioned. Moreover, most studies have few patients with high-grade VUR. Hence, we retrospectively analyzed a large cohort of patients with primary high-grade and low-grade VUR and assessed risk factors for renal damage and clinical morbidity. MATERIAL AND METHODS: We included patients (<18 years) at diagnosis with low-grade (1-3) or high-grade (4-5) primary VUR and noted their clinical history and presence of hypertension, low eGFR (<60ml/in/1.73 m2), renal scarring (focal or generalised) and reduced differential renal function (DRF; <45%). Risk factors were assessed (in patients and renal units) by logistic regression and generalised estimating equation. RESULTS: Of 399 primary VUR patients, 255 (64%) had high-grade VUR. Indications for voiding cystourethrogram were recurrent UTI (38%), first UTI (28%) and antenatal hydronephrosis (17%). At diagnosis, 252 (65%) had renal scars (focal in 170 [44%], generalised in 82 [21%]), and 188 (47%) had reduced DRF. High-grade VUR patients were more likely than low-grade VUR patients to have renal scarring (75% vs. 49%, p < 0.01), low eGFR (23% vs. 13%, p = 0.04) and significant hypertension (26% vs. 13%, p = 0.02). High-grade VUR was associated with generalised scars (odds ratio [OR] 11, p < 0.001), focal scars (OR 3.1, p < 0.001) and reduced DRF (OR 2.3, p < 0.001) shown in the table. Male sex was a risk factor for generalised scars (OR 2.3, p = 0.005). Focal scars were associated with recurrent UTIs (OR = 1.8, p = 0.004) and reduced DRF (OR 1.4, p = 0.027). Patients with multiple focal scars were diagnosed at an older age (2 years [1,4] than those with single scars (1.5 years [1,4] or no scars (1 year [0, 3]), p = 0.04). DISCUSSION: The prevalence of renal damage and clinical morbidity at VUR diagnosis was higher than other studies. High-grade VUR patients had a greater prevalence of renal damage, low eGFR and hypertension than low-grade VUR patients and was a risk factor for focal scars, generalised scars and reduced DRF. Focal scars were independently associated with recurrent UTI. Those with multiple scars were diagnosed later than those with single scars or no scars. CONCLUSIONS: High-grade VUR was associated with renal damage and clinical morbidity. Our study highlights the importance of diagnosing VUR early to identify patients who may warrant long-term follow-up and intervention to minimize morbidity.

Prevalence of Vesicoureteral Reflux in Children with Urinary Tract Infection.

Vesicoureteral reflux (VUR) is reported in 30%-50% of children affected by urinary tract infection (UTI). We aimed to investigate the frequency of VUR in children presenting with UTI and the changes in its prevalence from birth up to 18 years. This research was an observational retrospective study in the nephrology clinic of an academic tertiary hospital during 2003-2016. Patients with UTI subjected to direct cystourethrography were enrolled (908 patients, 86.23% of girls and 13.77% of boys). They were aged from 3 days to 214 months (33 ± 33.2 months). VUR was observed in 419 of 908 (46.14%) cases. High-grade VUR (VUR Grades IV-V) and VUR were significantly more prevalent in boys (P = 0.001 for both). Only 9.2% of the VUR subjects were diagnosed after 5 years of age. The patients with VUR developed UTI at a significantly younger age compared with those without VUR (P = 0.0001). Abnormal kidney ultrasound results were significantly more common in patients with VUR than in those without VUR (P = 0.0001). The prevalence of VUR in the 1st, 2nd, 3rd, 4th, and 5th years of life was estimated to be 56.64%, 48.2%, 49.46%, 35.8%, and 45.07%, respectively. The highest and lowest VUR prevalence was 56.64% (1st year of life) and 0% (13-18 years). In addition, severe VUR was not an uncommon finding, and affected 10.7% of the total population. The results indicated a decrease in the prevalence of VUR with increased age when considering the five main age subgroups of childhood.

Evolution of congenital anomalies of urinary tract in children with and without solitary kidney.

BACKGROUND: We hypothesized that children with congenital solitary functioning kidney (CSFK) present forms of congenital urinary tract anomalies (CUTA) with higher chance of spontaneous resolution compared with patients with two kidneys. METHODS: We retrospectively selected 75 consecutive children with CUTA of the CSFK and 75 matched patients with unilateral CUTA but without CSFK (controls) with prenatal suspicion of unilateral CUTA and early evaluation. We compared the spontaneous CUTA resolution and the prevalence of kidney injury between groups at last follow-up. Patients and controls were clustered under the categories of "severe" and "non-severe" CUTA. RESULTS: The mean age at first and last follow-up was 0.17 ± 0.07 and 8.5 ± 5.2 years. Compared with controls, patients with CSFK had lower prevalence of severe CUTA at first evaluation; lower prevalence of febrile urinary tract infections, need of surgical correction, and higher rate of spontaneous CUTA resolution during follow-up; and a similar prevalence of mild kidney injury at last follow-up. CSFK compared with controls presented higher cumulative proportion of spontaneous resolution from severe CUTA (100 vs 41.8%; p < 0.001) and from the single CUTA sub-categories (severe vesicoureteral reflux, non-obstructive hydronephrosis, and megaureter). CONCLUSIONS: CSFK patients had lower prevalence of severe forms and better outcomes of their CUTA compared with controls. IMPACT: One-third of patients with congenital solitary functioning kidney (CSFK) present congenital urinary tract anomalies (CUTA) and manifest poorer outcomes compared with CSFK without CUTA. CSFK patients had lower prevalence of severe forms and better outcomes of their CUTA in spite of similar prevalence of kidney injury compared with controls. This adds evidence about disturbed nephrogenesis in CSFK patients and emboldens conservative management of many of their non-obstructive CUTA.

Risk factors of vesicoureteral reflux and urinary tract infections in children with imperforate anus: A population-based case-control study in Taiwan.

ABSTRACT: Imperforate anus (IA) is associated with several urological anomalies, including vesicoureteral reflux (VUR), a major contributor to high morbidity in patients with anorectal malformations. This retrospective study was performed to elucidate the risk factors of vesicoureteral reflux (VUR) and UTI in children with IA.We used the National Health Insurance Research Database (NHIRD) to estimate the frequency of congenital anomalies of the kidney and urinary tract (CAKUT) in children with IA. We also investigated the frequencies of VUR, UTI, and CAKUT in children with IA along with the risk factors of VUR.We enrolled 613 children between 2000 and 2008 (367 males and 246 females; 489 low-position IA and 124 high-position IA). High-position IA was associated with a significantly increased risk of VUR compared with low-position IA (OR: 2.68, 95% CI: 1.61, 4.45). In addition, children with IA along with CAKUT, hydronephrosis, or UTI had a higher risk of VUR (OR: 8.57, 95% CI: 3.75, 19.6; OR: 7.65, 95% CI: 4.48, 13.1; and OR: 31.8, 95% CI: 11.5, 88.3, respectively). UTI, as well as chromosomal anomalies, were more frequent in children with high-position IA.Patients with a high-position IA had a greater risk of VUR, particularly those with CAKUT, hydronephrosis, or UTI. Such patients must periodically undergo urinalysis to screen for UTI and early voiding cystourethrogram to rule out VUR and prevent consequent renal damage. Chromosomal analysis is suggested to rule out Down syndrome.

OUR EXPERIENCE WITH CONTRAST-ENHANCED VOIDING UROSONOGRAPHY.

Vesicoureteral reflux (VUR) is one of the most common anomalies of the urinary system in children. Contrast-enhanced voiding urosonography (ceVUS) is one of the best methods in VUR diagnosis. This study compared characteristics associated with VUR specific images and categorized patients according to a particular VUR grade. The study included 183 children. VUR was detected in 38.9% of patients, mean age 1.7±1.1 years. Grade II VUR was most common (60.3%), followed by grade III (29.4%). Study results showed that VUR occurred irrespective of age, gender, previous ultrasound findings, causative agent, and severity of urinary tract infection (UTI). VUR was more common in children with recurrent UTI. In the group of children with the first UTI not caused by Escherichia coli or with recurrent UTI, boys more commonly suffered from severe VUR (grade IV-V; 66.7%), while girls suffered from moderate VUR (grade II-III; 100%). In this study, the incidence of VUR in prenatally diagnosed hydronephrosis was 28.6%. It is necessary to develop an algorithm for the treatment of children after UTI in Croatia, which should include ceVUS. All children with possible VUR should be referred to a specialized center where it is possible to perform ceVUS.

Diagnostic Values of Kidney Ultrasonography for Vesicoureteral Reflux (VUR) and High Grade VUR.

INTRODUCTION: Vesicoureteral reflux (VUR) is a well-known risk factor for urinary tract infection (UTI). We aim to define diagnostic values of kidney ultrasonography (US) as a predictor of VUR and high grades VUR in children presented by UTI. METHODS: This retrospective study was conducted during October 2003 to 2016. Children aged ≤ 18 years with history of UTI who had underwent kidney US and direct cystography [voiding cystourethrography (VCUG) or radionuclide cystography (RNC)] enrolled in the study. Diagnostic values of hydronephrosis, hydro ureter, renal scaring, hydroureteronephrosis, decreased kidney size and abnormal kidney US for diagnosis of VUR and high grades VUR (grades IV-V) were evaluated. RESULTS: Hydro-ureter, renal scaring, and hydroureteronephrosis were significantly more prevalent in VUR+ versus VUR- cases, also in higher grades compared with lower grades (grades I-III) VUR (P < .05 for all). Additionally, hydronephrosis was more common in VUR+ compared with VUR- patients (P < .0001). As a predictor of VUR and higher grades of VUR, abnormal kidney US had the highest sensitivity (24.87% and 40.84%, respectively), abnormal kidney US and hydro ureter reached the highest NPV (70.42% and 81.27%, respectively), hydroureteronephrosis and hydro ureter showed the highest accuracy (68.51% and 82.21%, respectively) . CONCLUSION: Kidney US is a valuable screening test, abnormal renal US significantly increases the probability of VUR and high grades VUR , but if used as the only screening test , about 2/3 and 1/3 and 20% of VUR , high grades VUR and grade V VURs will be missed. DOI: 10.52547/ijkd.5966.