Society For Fetal Urology Grade Research Articles

Are pressure pop-offs beneficial to the bladder in boys with posterior urethral valves?

Pressure pop-offs, such as high-grade vesicoureteral reflux with renal dysplasia, have historically been considered beneficial for renal and bladder outcomes in boys with posterior urethral valves (PUV). Recent longer-term studies have called into question the beneficial effects of pop-offs on renal function. To evaluate how pop-offs affect bladder outcomes in boys with PUV. At a single-center, the electronic medical records of boys with PUV who underwent valve ablation from 2000 to 2014 were retrospectively reviewed for bladder and continence outcomes. Patients were excluded due to presentation after one year of age, age at last follow-up <1 year, lack of urodynamic study (UDS), lack of voiding cystourethrogram, or concomitant prune belly syndrome. Between patients with and without pop-offs, the following outcomes were compared: prevalence of significant hydronephrosis (Society for Fetal Urology grade 3 or 4) prior to valve ablation and at last follow-up, nadir creatinine level, classification of initial UDS, type of medical and/or surgical interventions, dryness during the day and toilet-training status at last follow-up (among patients ≥4 years), and age at toilet-training. For patients with multiple UDS, initial and latest UDS were compared. 48 patients met inclusion criteria, of whom 31 (65%) had pop-offs and 17 (35%) did not. Median age at last follow-up was 5.9 years (range: 1.0-12.2 years). Patients with pop-offs were more likely to have unsafe initial UDS (26% vs. 12%, p=0.15) but less likely to have high voiding pressures at their latest UDS (15% vs. 50%, p=0.03). Patients with pop-offs were more likely to have used clean intermittent catheterization (26% vs. 0%, p=0.04) and were less likely to be toilet-trained by age 4 (76% vs. 100%, p=0.15) or dry during the day at last follow-up (56% vs. 92%, p=0.06). Toilet-trained patients with pop-offs were toilet-trained by an earlier age than patients without pop-offs (3 vs 4 years, p=0.04). The results of the present retrospective study show that patients with pop-offs required more extensive interventions to achieve continence, and achieved continence and toilet-training less frequently than patients without pop-offs. Additionally, our results demonstrated that patients with pop-offs had worse bladder dynamics initially, which may suggest that pop-offs are a manifestation of more excessive pressure build-up prior to valve ablation. Among boys with posterior urethral valves who present in the first year of life, pop-offs do not appear to impart significant benefit to bladder outcomes and may indicate more severe bladder dysfunction.

Do current scientific reports of hydronephrosis make the grade?

In December 2014, Nguyen etal. introduced the Upper Tract Dilation (UTD) classification scheme, hoping to unify multiple disciplines when describing ultrasound imaging of congenital hydronephrosis. We hypothesized that the academic community has been slow to adopt its use in publications. To evaluate which hydronephrosis grading systems were currently preferred in publications. A PubMed® search for hydronephrosis was performed, and abstracts between May 2017 and May 2019 were reviewed. The following data points were collected from the 197 manuscripts meeting inclusion criteria: journal, first and senior author specialty, country, type of article, primary pathology, and classification of hydronephrosis when present. Differences between use of classification system, and author specialty, manuscript type, and pathology were evaluated. First and/or senior author specialties were most commonly pediatric urology, urology, pediatric surgery, and pediatric nephrology. The manuscripts were comprised of retrospective studies (48.2%), prospective studies (25.4%), case reports (15.7%), review articles (9.1%), and systematic reviews (1.5%). The most common pathologies were hydronephrosis (36.5%) and ureteropelvic junction obstruction (21.3%). Over 20% of manuscripts did not categorize hydronephrosis at all. The UTD classification was used by 5.6%, while Society for Fetal Urology (SFU) grading was used by 37.1% and Anterior-Posterior Diameter (APD) measurements by 32.5%. The Summary Table presents grading system by manuscript type, specialty, and pathology. There is great variability in hydronephrosis grading. One potential weakness of our study is that sufficient time may not have passed for the UTD system to be adopted. Researchers may need more time to complete and publish their studies, or could be awaiting further validation of UTD utility. They could also be hesitant to change systems when it is unknown if one classification schema is superior to another, either in general or for specific diagnoses. Another weakness is that this study does not quantify what, if any, systems are used clinically. Some attempt to provide objective classification would help clarify the implications of the manuscript for research or clinical applications. Reviewers should ensure that where possible, adequate descriptions of hydronephrosis are included. Education outreach to other specialties may help increase objective grading in research. The UTD system is not commonly utilized in the literature. SFU grading is applied most commonly, followed by APD measurements. Over one third of manuscripts used no classification system or descriptive terminology.

The role of antibiotic prophylaxis in mild to moderate isolated hydronephrosis detected in antenatal screening.

PurposeTo determine whether continuous antibiotic prophylaxis (CAP) could prevent urinary tract infection (UTI) in mild to moderate antenatal isolated hydronephrosis (IH), characterized by hydronephrosis without ureter and bladder abnormalities, and anteroposterior renal pelvis diameter <16 mm and the Society for Fetal Urology grade <4, in neonatal renal ultrasound.Materials and MethodsEighty neonates aged 7 to 30 days, with antenatal hydronephrosis and mild to moderate IH on neonatal renal ultrasound, were recruited from August 2015 to December 2016. Neonates were randomly assigned to CAP until hydronephrosis resolution or aged 12 months (CAP group, n=40) or to watchful observation (control group, n=40). The primary outcome was UTI. The probability of UTI was compared between the randomized groups using the Kaplan–Meier method and the log-rank test.ResultsNonadherence occurred in 6/40 parents in the CAP arm (15.0%). Thus, only 34 patients received CAP. UTI occurred in 5/34 patients in the CAP group (14.7%) and in 4/40 controls (10.0%). The probability of UTI was increased in the CAP group (hazard ratio, 1.38; 95% confidence interval, 0.37–5.16; p=0.63). UTI caused by cotrimoxazole resistant bacteria was four times higher in the CAP group than in controls (relative risk, 4.0; 95% confidence interval, 1.2–13.5; p=0.02). The trial was prematurely terminated due to the negative impact of CAP on bacterial sensitivity.ConclusionsThe benefits of CAP in infants with mild to moderate IH were inconclusive. CAP conferred a high risk of resistant bacterial organisms when UTI occurs.

The learning curve for robotic-assisted pyeloplasty in children: Our initial experience from a single center.

Background:Robotic-assisted pyeloplasty surgery has become the preferred approach of ureteropelvic junction obstruction (UPJO) in pediatrics. However, to our knowledge, there is limited data on the learning curve for robotic-assisted pyeloplasty in children and no similar study from Saudi Arabia.Aims:The objective of the study was to evaluate the progression of the surgical team performing robotic-assisted laparoscopic pyeloplasty (RALP) and to assess the feasibility of the RALP in children, since it is having been recently started in the Kingdom.Settings and Design:Retrospective charts and surgical videos review at the tertiary care centre.Subjects and Methods:After approval from the internal review board (IRB), we reviewed the surgical video recording of the RALP procedure of 15 patients presented with UPJO from January 2016 to October 2017. Statistical analysis was done for the variables includes dissection time, pyelotomy, anastomosis on both sides, and total surgery time and calculated in minutes. Renal ultrasound reviewed to assess any change in grade.Results:Fifteen patients with UPJO underwent RALP. Of 15 cases, nine were primary and six cases as secondary UPJO. The median age was 8 (3–15) years. Out of 15 cases, 13 and 2 patients diagnosed as Society for Fetal Urology grades of 4 and 3, respectively. Total operative time was prolonged in secondary group as compared to primary pyeloplasty group (mean [standard deviation (SD)]: 166.3 [35.1], range: 125–223, P = 0.0028 versus mean (SD): 149.17 (30.4), range: (114–207), P = 0.0008). The success rate was 100% in primary and 84% in secondary cases. The median length of follow-up was 12.0 (7.0–18.0) and 10.0 (8.0–12.5) months in primary and secondary cases, respectively. The overall complication rate was 13% (2/15) (Clavien grade: 1–2).Conclusions:The evaluation of the learning curve of RALP for this group of patients concluded that total operative time for RALP, performed by the pediatric urology team, steadily decreased with collective surgical experience.

A clinical predictive model of renal injury in children with isolated antenatal hydronephrosis.

BackgroundAntenatal hydronephrosis (ANH) affects ∼1–5% of pregnancies. The aim of this study was to develop a clinical prediction model of renal injury in a large cohort of infants with isolated ANH.MethodsThis is a longitudinal cohort study of 447 infants with ANH admitted since birth between 1989 and 2015 at a tertiary care center. The primary endpoint was time until the occurrence of a composite event of renal injury, which includes proteinuria, hypertension and chronic kidney disease (CKD). A predictive model was developed using a Cox proportional hazards model and evaluated by C-statistics.ResultsRenal pelvic dilatation (RPD) was classified into two groups [Grades 1–2 (n = 255) versus Grades 3–4 (n = 192)]. The median follow-up time was 6.4 years (interquartile range 2.8–12.5). Thirteen patients (2.9%) developed proteinuria, 6 (1.3%) hypertension and 14 (3.1%) CKD Stage 2. All events occurred in patients with RPD Grades 3–4. After adjustment, three covariables remained as predictors of the composite event: creatinine {hazard ratio [HR] 1.27, [95% confidence interval (CI) 1.05–1.56]}, renal parenchyma thickness at birth [HR 0.78(95% CI 0.625–0.991)] and recurrent urinary tract infections [HR 4.52 (95% CI 1.49–13.6)]. The probability of renal injury at 15 years of age was estimated as 0, 15 and 24% for patients assigned to the low-risk, medium-risk and high-risk groups, respectively (P < 0.001).ConclusionOur findings indicate an uneventful clinical course for patients with Society for Fetal Urology (SFU) Grades 1–2 ANH. Conversely, for infants with SFU Grades 3–4 ANH, our prediction model enabled the identification of a subgroup of patients with increased risk of renal injury over time.

Does de novo hydronephrosis after pediatric robot-assisted laparoscopic ureteral re-implantation behave similarly to open re-implantation?

While open ureteral re-implantation surgery is the gold standard for surgical correction of vesicoureteral reflux (VUR), robot-assisted laparoscopic ureteral re-implantation via an extravesical approach (RALUR-EV) has become a minimally invasive alternative. Previous studies have shown that transient hydronephrosis after open re-implantation can occur in up to 28% of patients. However, previous studies have also shown that de novo hydronephrosis after open re-implantation is not predictive of final differential renal function. A retrospective review was performed to characterize the natural history of postoperative hydronephrosis after RALUR-EV for primary VUR in pediatric patients. A retrospective chart review of a single-surgeon series was performed for pediatric patients who underwent RALUR-EV for primary VUR. The severity of de novo hydronephrosis was assessed using the Society for Fetal Urology (SFU) grading system via renal ultrasound at the 1-month postoperative follow-up. Renal ultrasound was performed at least every six months. Radiographic success was defined as complete resolution of VUR on the voiding cystourethrogram at the 4-month mark. Patient demographics, surgery duration, length of hospital stay, pre-operative and postoperative VUR grades, and follow-up time periods were collected. Patients with other associated urinary pathology and patients lost to follow-up were excluded from the study. A total of 87 patients (121 kidney units) with primary VUR who underwent RALUR-EV met the inclusion criteria. SFU grade 1-3 hydronephrosis was noted in 30.3% (36/119) of kidney units at the 1-month mark, but 83.9% (26/31) cases with hydronephrosis completely resolved in a median time of 7.9 months (range: 3.4-21.0 months), and all four cases with unresolved hydronephrosis were downgraded to SFU grade 1 without the need for intervention. A radiographic success rate of 96% was demonstrated in this cohort, which is comparable with that of historical open re-implantation series. A similar rate of de novo hydronephrosis was also noted in this cohort when compared with that of previous open re-implantation series, but de novo hydronephrosis after RALUR-EV had a similar or more rapid resolution rate than that previously reported after open intravesical and extravesical re-implantation series. De novo hydronephrosis after RALUR-EV behaves similarly to de novo hydronephrosis after open ureteral re-implantation, where de novo hydronephrosis is present in up to 30% of pediatric patients who underwent RALUR-EV. The hydronephrosis self-resolves without the need for intervention in the overwhelming majority of casesand resolves at a median time of 7.9 months after surgery.

Ultrasound evaluation for prediction of outcomes and surgical decision in fetal hydronephrosis.

Fetal hydronephrosis (HY) is a frequent congenital condition, which may be detected by prenatal ultrasound. Society for Fetal Urology (SFU) and anterior-posterior diameter (APD) grading are two major grading systems based on ultrasonography. The present study aimed to assess the predictive value of the SFU and APD grades in patients with fetal HY. A total of 162 patients with 234 kidneys affected by HY were included in the present study. The SFU and APD grades were determined from the ultrasound images at 38 gestational weeks, and a 12-month follow-up was performed after birth. The associations of the SFU and APD grades with the outcome of fetal HY, including HY regression, and post-partum surgery were examined. In the present study, 16 patients with 17 kidneys were diagnosed with pathological HY, and stenosis at the ureteropelvic junction was demonstrated to be a leading cause of pathological HY. Among the 234 kidneys affected by HY, 161 kidneys were scored as SFU grade I, 57 as SFU grade II, 7 as SFU grade III and 9 kidneys as SFU grade IV. According to the APD grading system, 112 kidneys were determined as having low, 104 as having moderate and 18 as having severe HY. The SFU and APD grades were demonstrated to be independently associated with the occurrence of pathological HY by logistic regression analysis with a high diagnostic accuracy to distinguish pathological and physiological HY cases as evidenced by the results of ROC analysis. In addition, univariate and multivariate logistic regression analysis indicated that patients with spontaneous HY regression usually had low SFU and APD grades. Furthermore, the rate of surgery was increased in the group of patients with high SFU or APD grades, and these two systems were identified as independent predictors for the requirement of surgery by Kaplan-Meier analysis. Patients with pathological HY had high SFU and APD grades, and these two grading systems may be used as reliable predictors for the outcome of fetal HY, including HY regression, and post-partum surgery.

Surgical decision-making in infants with suspected UPJ obstruction: stakeholder perspectives

Although there are significant demographic and clinical variations in treatment decisions for infants with high-grade hydronephrosis concerning for ureteropelvic junction obstruction (UPJO), there has been little research on the roles of parents and surgeons in the surgical decision-making (DM) process. The purpose of this study was to understand parents' and surgeons' perceived roles in the surgical DM process for infants with high-grade hydronephrosis. Semistructured interviews were conducted with pediatric urologists from three regionally diverse tertiary referral sites and parents of infants diagnosed and treated for unilateral Society for Fetal Urology grade 3 or 4 hydronephrosis at one tertiary pediatric urology practice. Purposive sampling was used to ensure adequate representation of parents based on treatment choice, patient gender, race/ethnicity, and distance from the practice. Survey domains included(1) discussions about diagnosis and treatment options, (2) factors guiding treatment choice, and (3) participants' role in the DM process. Transcribed data and field notes were analyzed using a team-based, inductive grounded theory qualitative approach. Thirteen physicians and 32 parents were interviewed between November 2016 and November 2017. Parents and surgeons agreed that the surgeon was best equipped to guide treatment decisions because of their clinical knowledge and experience. Parents reported that their trust in the surgeon was the primary factor in their decisions. Surgeons reported tailoring discussions with parents to not only educate them about treatment options but also to develop an ongoing relationship with parents. Both parents and surgeons reported being satisfied with their roles in the DM process. This study suggests that parental trust in the surgeon and surgeon recommendations drive DM. This may be due to a lack of explicit discussion of options or of parental values and preferences for care. Limited discussions may also impact parental understanding of risks and potential complications. These findings are similar to those of prior studies in adults and children considering elective surgery. In this study, parents and surgeons reported that surgeon recommendations, rather than parent preferences, guide treatment choices for infants with suspected UPJO. Both parents and surgeons are satisfied with a physician-driven approach to DM, suggesting that, in situations where the perceived risk is low and parental knowledge is limited, parents may find a physician-led approach beneficial. Data gleaned from this study will be used to inform future quantitative studies evaluating factors guiding surgeon recommendations for treatment and their associations with underlying treatment variation.

Time to resolution of isolated antenatal hydronephrosis with anteroposterior diameter ≤ 20 mm.

Data regarding spontaneous resolution of mild hydronephrosis consist of different etiologies, and hence, it is heterogeneous. The aim of this study is to evaluate spontaneous resolution rates and the time to complete resolution of antenatally detected isolated hydronephrosis in patients with renal pelvis antero-posterior diameter (RPAPD) ≤ 20mm. Retrospective chart review of patients who were admitted to our pediatric nephrology clinic for the evaluation of antenatal hydronephrosis between 2011 and 2017 was conducted. Patients that had hydronephrosis with RPAPD ≤ 20mm, < SFU (Society for Fetal Urology) grade IV on initial postnatal evaluation, and ≥ 3months of follow-up with at least two renal ultrasounds (US) were included. Complete resolution of hydronephrosis was regarded as SFU grade 0 with a RPAPD of < 7mm. Patients with ureteric and lower urinary tract abnormalities were excluded. There were a total of 276 patients who met the inclusion criteria. Median follow-up was 16months (range 3-96months). Hydronephrosis completely resolved in 198 patients (71.7%). Surgery was not required in any of the patients; however, nine patients (3.3%) showed progression to higher grades of hydronephrosis or increase in AP diameter. Median time to complete resolution of hydronephrosis was 6months (range 2-35months) in our study. Those with AP diameter < 10mm became normal in median of 5months, while it took median 11months for patients with AP diameter 10-20mm to become normalized (p < 0.001).Conclusion: Isolated antenatal hydronephrosis with RPAPD ≤ 20mm would spontaneously resolve in 71.7% of the cases. Resolution may be expected to happen in 3years, while the majority will take place in the first year of life. What is Known: • Antenatal hydronephrosis comprises an important amount of clinical visits. • Spontaneous resolution rates differ for various etiologies. What is New: • Isolated antenatal hydronephrosis with RPAPD ≤ 20mm completely resolves within 3years in approximately 72% of the cases. • Resolution can be observed within the first year of life in most of the cases.

Natural course of isolated mild congenital hydronephrosis: A 2-year prospective study at a single center in Japan.

To determine a follow-up plan for mild congenital hydronephrosis in Japanese individuals. Neonates at Kansai Medical University Hospital (Hirakata, Osaka, Japan) who were diagnosed with mild congenital hydronephrosis - defined as a Society for Fetal Urology grade1 or 2 - at 1-month old by abdominal ultrasonography between 2014 and 2016 were enrolled. These patients were encouraged to undergo repeated abdominal ultrasonography for 2years every 3months to investigate the course of congenital hydronephrosis. Among 1009 neonates, congenital hydronephrosis was detected in 118 affected renal units of 100 (9.9%) patients. According to the definition of the Society for Fetal Urology, 118 affected renal units were graded as grade1 in 87 (74%), grade2 in 30 (25%), grade3 in one (1%) and grade4 in 0 units. Among them, 117 affected renal units of mild congenital hydronephrosis comprising grades1 and 2 were subjected to ultrasonographic evaluation to monitor the natural course. The rates of resolution at 7, 10, 13, 16, 19, 22 and 25 months after birth in Society for Fetal Urology grades 1 and 2 cases were 60% and 8%, 77% and 19%, 90% and 32%, 92% and 40%, 95% and 52%, 96% and 56%, and 99% and 60%, respectively. Grade1 congenital hydronephrosis does not need to be followed up, because it mostly shows spontaneous resolution by 2years of follow up without any complications. However, ultrasonographic examinations at 1-year intervals for grade2 congenital hydronephrosis are recommended to determine the subsequent follow-up plan of patients.

Reliability of society of fetal urology and Onen grading system in fetal hydronephrosis.

ObjectiveTo evaluate the reliability of the Society for Fetal Urology (SFU) and Onen grading systems for fetal hydronephrosis in prenatal ultrasound according to the level of experience of the examiner.MethodsWe reviewed the prenatal ultrasound images of 146 fetuses (292 kidneys) that were diagnosed as having hydronephrosis between January 2005 and December 2014. One expert and two trainees assessed the prenatal renal ultrasound images using the SFU and Onen grading systems. The three examiners independently assessed each ultrasound image with both grading systems and reassessed the same images after 7 to 14 days. Cohen's kappa statistic was used to estimate intra- and inter-observer reliability in prenatal ultrasound images according to training level.ResultsThe intra-observer reliability of the SFU grading system (κ 0.873–0.945) showed almost perfect agreement and that of the Onen grading system (κ 0.749–0.913) showed substantial to almost perfect agreement. The overall inter-observer reliability of the SFU grading system (κ 0.620–0.825) showed substantial to almost perfect agreement and that of the Onen grading system (κ 0.618–0.724) showed substantial agreement. The weighted kappa value of inter-observer agreement was 0.223 to 0.400 for SFU grade 1 and 0.064 to 0.346 for SFU grade 3. For Onen grading, the inter-observer agreement was 0.012 to 0.214 for grade 2 and 0.193 to 0.334 for grade 3.ConclusionBoth the SFU and Onen grading systems showed good intra-observer agreement in prenatal ultrasonography. The inter-observer agreement was decreased in SFU grades 1 and 3 and Onen grades 2 and 3. Therefore, more focus should be given to SFU grades 1 and 3 and Onen grades 2 and 3 for trainees.

Ultrasound Markers in Fetal Hydronephrosis to Predict Postnatal Surgery.

Parents confronted with the finding of antenatal hydronephrosis (ANH) are particularly interested in whether their baby will need postnatal surgery. The objective of this study was to predict ANH requiring surgery on the basis of the fetal anteroposterior renal pelvic diameter (APRPD) and the Society for Fetal Urology (SFU) grading system. The medical records of 179 patients with the finding of ANH were reviewed retrospectively. ANH was graded according to the SFU grading system. Prenatal ultrasound examinations were correlated to postnatal outcome, which was divided into three groups: prenatal resolution, conservative management and surgical treatment. 58 (32.4 %) cases were classified as prenatal resolution, 89 (49.7 %) babies were assigned to the conservative outcome group and 32 (17.9 %) patients needed surgical repair. Postnatal surgery was best predicted in the second trimester (area under the receiver operating characteristics curve: 0.839) by an APRPD cut-off of 8.3 mm (sensitivity: 77.8 %; specificity: 85.7 %; PPV of 53.9 %, NPV of 94.7 %). The combination of the parameters "progression of SFU grade" and SFU grade 3 or 4 achieved a sensitivity of 84.4 % and a specificity of 80.3 % for the prediction of surgery. Second-trimester APRPD is a useful parameter for predicting the risk for postnatal surgery. The SFU grade should be assessed in every prenatal ultrasound examination as some further risk estimates can be made based on its dynamics over time.

Predictors of Recoverability of Renal Function after Pyeloplasty in Adults with Ureteropelvic Junction Obstruction

Background: This study aimed to identify factors predicting the recoverability of renal function after pyeloplasty in adult patients with ureteropelvic junction obstruction. Methods: We retrospectively reviewed 138 adults with unilateral renal obstruction-induced hydronephrosis and who underwent Anderson-Hynes dismembered pyeloplasty from January 2013 to January 2016. Hydronephrosis was classified preoperatively according to the Society for Fetal Urology (SFU) grading system. All patients underwent Doppler ultrasonography, excretory urography, computed tomography, and technetium-99m-diethylenetriamine pentaacetic acid radioisotope (99mTc DTPA) renography before and after surgery. Renal resistive index (RRI) and 99mTc DTPA renography were repeated at 1, 3, 6, and 12 months. Results: Multivariate analysis identified age, renal pelvic type, SFU grade, preoperative RRI, decline of RRI, and renal parenchyma to hydronephrosis area ratio (PHAR) as independent predictors of renal function recoverability after pyeloplasty. However, preoperative RRI and RRI decline were not significantly associated with recoverability of renal function in patients aged >35 years. Lower preoperative RRI, greater decline in RRI, higher PHAR, lower SFU grade, and extrarenal pelvis were associated with greater improvements in postoperative renal function. Conclusions: Preoperative differential renal function cannot independently predict the recoverability of postoperative renal function in adult patients with unilateral renal obstruction-induced hydronephrosis. SFU grade, renal pelvic type, PHAR, preoperative RRI, and decline in RRI were significantly associated with the recoverability of renal function in adult patients aged <35 years, while only SFU grade, renal pelvic type, and PHAR were significantly associated with renal function recoverability in patients aged ≥35 years. Renal function recovery was better in patients younger than 35 years when compared with older patients.

Isolated low grade prenatally detected unilateral hydronephrosis: do we need long term follow-up?

ABSTRACTPurpose:To assess the need for postnatal evaluation and the medium term outcome in patients with isolated unilateral low grade prenatally detected hydronephrosis.Materials and Methods:We prospectively selected 424 patients (690 kidney units) with a prenatal diagnosis of urinary tract dilatation between 2010 and 2013. We included only those patients with isolated unilateral low-grade hydronephrosis who underwent at least 2 postnatal ultrasound examinations. The Society for Fetal Urology (SFU) grading system was utilized for assessment of the hydronephrosis. We excluded patients with bilateral dilation or other urological abnormalities. The fate of hydronephrosis including resolution, stability or worsening was documented.Results:A total of 66 infants (44 boys and 22 girls) with antenatally diagnosed unilateral urinary tract dilation (23 right and 43 left) were identified. Ultrasounds showed SFU grade 1 hydronephrosis in 32 patients (48%) and SFU grade 2 hydronephrosis in 34 (52%). After a mean follow-up period of 32 months (range 12 to 60), 37 patients (56%) had complete resolution of hydronephrosis while the remaining 29 were stable (44%). None of our patients developed UTIs during follow-up and none required surgical intervention.Conclusions:Prenatally detected, isolated unilateral low-grade hydronephrosis usually have a favorable prognosis. All cases in our cohort showed either stability or resolution of hydronephrosis without any harmful consequences. Based on our findings on medium-term in this category of patients, long-term follow-up is not warranted.

Influence of postnatal hydroureter in determining the need for voiding cystourethrogram in children with high-grade hydronephrosis

ObjectiveTo evaluate the utility of hydroureter (HU) to identify high-grade vesico-ureteric reflux (VUR) in patients with high-grade postnatal hydronephrosis (PH). Patients and methodsWe retrospectively reviewed patients’ charts that had antenatal hydronephrosis from 2008 to 2014. Patients were excluded if they presented with febrile urinary tract infection (fUTI), neurogenic bladder, posterior urethral valve, multi-cystic dysplastic kidney, and multiple congenital malformations. We reviewed postnatal ultrasonography images and patients with Society of Fetal Urology (SFU) Grades 3 and 4 hydronephrosis with a renal pelvic antero-posterior diameter of ≥10 mm were included. The ureter was assessed and considered dilated if the ureteric diameter was ≥4 mm. The voiding cystourethrogram (VCUG) studies, fUTI incidence, and surgical reports were reviewed. ResultsOf the 654 patients reviewed, we included 148 patients (164 renal units) of whom 113 (76.4%) were male and 35 (23.6%) female. SFU Grade 3 PH was identified in 49% of the renal units, with the remaining 51% being SFU Grade 4. HU was found in 50/164 renal units and was not detected in the remaining 114 units. VUR was diagnosed in four units (3.5%) without HU (low-grade VUR); whilst it was detected in 19 units (38%) with HU (72.7% were high-grade VUR) (P < 0.001). VUR was diagnosed on the contralateral side in four/105 patients with PH without HU and diagnosed in 10/43 patients with PH with HU (P < 0.001). During a median follow-up of 25.9 months, none of the renal units that had VUR without HU developed UTI or had surgeries. ConclusionLow-grade uncomplicated VUR was diagnosed in 3.5% of renal units without HU. Our results support limiting the use of VCUG to renal units with PH if associated with HU.

Society for Fetal Urology Classification vs Urinary Tract Dilation Grading System for Prognostication in Prenatal Hydronephrosis: A Time to Resolution Analysis

The Urinary Tract Dilation grading system for prenatal hydronephrosis was introduced to address potential shortcomings of the Society for Fetal Urology classification. Hydronephrosis resolution is an important patient outcome and is frequently discussed during family counseling. We compared these 2 grading systems and their ability to predict time to hydronephrosis resolution. We prospectively screened 855 patients with prenatal hydronephrosis due to ureteropelvic junction obstruction-like hydronephrosis, nonrefluxing primary megaureter or vesicoureteral reflux between 2009 and 2015. Of the patients 454 were excluded due to surgery, late referral, absence of postnatal dilatation or presence of other anomalies, resulting in 401 eligible patients (of whom 81% were male) to be included for analyses. Hydronephrosis grades collected at baseline and last followup were compared to identify resolution trends through time. Hydronephrosis resolution was defined as renal pelvis anteroposterior diameter 10 mm or less at last followup. Time to resolution was analyzed using Cox proportion regression. Of 401 patients 328 (82%) had resolution during a mean ± SD followup of 24 ± 18 months (maximum 107). Cumulative resolution rate at 3 years was 98% for Society for Fetal Urology grade I hydronephrosis, 87% for grade II, 76% for grade III and 57% for grade IV. The 3-year hydronephrosis resolution rate was 90% for Urinary Tract Dilation postnatal grade 1 (low risk), 81% for grade 2 (intermediate risk) and 71% for grade 3 (high risk). Patients with distinctive baseline hydronephrosis grades (classified by Society for Fetal Urology or Urinary Tract Dilation system) had significantly different resolution times for hydronephrosis (p <0.001). Counseling families regarding time to resolution of prenatal hydronephrosis should remain the same whether using Society for Fetal Urology or Urinary Tract Dilation grading system.

Predictive value of cortical transit time on MAG3 for surgery in antenatally detected unilateral hydronephrosis caused by ureteropelvic junction stenosis

In children with antenatally detected hydronephrosis caused by ureteropelvic junction (UPJ) stenosis, the main challenge is preserving renal function by identifying children who require early surgical intervention from those for whom watchful waiting may be appropriate because of the potential for spontaneous resolution without a significant loss of renal function. To assess the impact of initial cortical transit time (CTT) on technetium-99m mercaptoacetyltriglycerine (MAG3) diuretic renogram on the need for surgery in children with antenatally detected unilateral hydronephrosis caused by UPJ stenosis. We retrospectively reviewed the medical records of 33 patients with antenatally detected unilateral hydronephrosis caused by UPJ stenosis who were managed at our institution between 2006 and 2014. Delayed CTT was defined as the absence of activity in the subcortical structures within 3min of tracer injection on a MAG3 scan. The surgical indication includes symptomatic UPJ stenosis, seriously deteriorating hydronephrosis with parenchymal thinning on serial USG, split renal function <40%, or progressive deterioration of split renal function (>5%) on a MAG3 scan. This study analyzed and compared the initial level of Society for Fetal Urology grade, anteroposterior diameter (APD), split renal function, drainage pattern on a diuretic renogram, and CTT with the need for surgery. Of the 33 children, 16 were classified into the delayed CTT group and 17 were placed in the normal CTT group. During the follow-up period (mean 31.8 months), surgery was needed in 75.0% (12/16) of patients in the delayed CTT group and in 5.9% (1/17) of those in the normal CTT group. Multivariate analysis showed that delayed CTT on initial MAG3 scan and APD on initial ultrasonography were independent predictive factors of the need for surgery. In this era of conservative management of antenatally detected hydronephrosis caused by UPJ stenosis, it is critical to identify which measurement on an image study is the most reliable for predicting the need for surgery by reflecting functional deterioration. In this study, multivariate analysis revealed that CTT on the initial MAG3 scan was an independent predictive factor of the need for surgery. In addition, CTT showed high negative predictive value for surgical need in children with antenatally detected unilateral hydronephrosis caused by UPJ stenosis. CTT on an initial MAG3 scan may be a useful predictor of the need for surgery in children with antenatally detected unilateral hydronephrosis caused by UPJ stenosis.

Parenchyma-to-hydronephrosis Area Ratio Is a Promising Outcome Measure to Quantify Upper Tract Changes in Infants With High-grade Prenatal Hydronephrosis

To explore the value of renal parenchyma-to-hydronephrosis area ratio (PHAR) in detecting trends of hydronephrosis (HN) improvement or worsening and response to surgical intervention. Initial and follow-up sagittal renal ultrasound images of patients entered into a prenatal HN database from 2008 to 2016, with baseline Society for Fetal Urology (SFU) grades III and IV HN and without vesicoureteral reflux, were evaluated using National Institutes of Health-sponsored image-processing software. Renal parenchymal area, hydronephrosis area (HA), PHAR, anteroposterior diameter (APd), and SFU grade were captured at baseline and most recent visit. Data were analyzed based on the need for surgical intervention to address obstruction. Out of 193 infants (159 boys; 135 left side), 58 (30%) underwent surgery. Patients managed surgically compared with those managed nonsurgically had worse baseline HN severity markers: SFU grade (3.6 ± 0.5 vs 3.1 ± 0.4; P <.001), urinary tract dilation classification (2.7 ± 0.5 vs 2.2 ± 0.4; P <.001), APd (20.3 ± 10.1 vs 12.8 ± 8.0; P <.001), HA (10.0 ± 6.6 vs 4.7 ± 2.8; P <.001), and PHAR (1.3 ± 1.0 vs 3.0 ± 2.9; P <.001); but both patient groups had similar renal parenchymal area (9.4 ± 3.5 vs 9.7 ± 2.8; P = .5). At last follow-up, the following discrepancies persisted: SFU grade (2.3 ± 1.0 vs 1.7 ± 1.0; P <.001), urinary tract dilation classification (1.5 ± 0.7 vs 1.0 ± 0.7; P <.001), APd (11.7 ± 8.0 vs 7.7 ± 5.7; P <.001), and HA (6.4 ± 5.1 vs 3.6 ± 2.7; P <.001); however, PHAR was equalized for both groups (7.2 ± 14.0 vs 7.1 ± 6.1; P = .9). By concurrently considering changes in renal parenchyma and degree of HN, we found that PHAR appears to be a promising parameter that reflects similarities between patients managed surgically and those managed nonsurgically, despite initial discrepancies. Our data suggest that this variable may provide reassurance and a more objective assessment of improvement after surgery compared with other traditional ultrasound outcome measures.

Serum and urinary thioredoxin concentrations are associated with severity of children hydronephrosis

BackgroundUreteropelvic junction obstruction (UPJO) is the most common cause of hydronephrosis in children. This study was to assess the relationship between serum thioredoxin (S-Trx) and urinary thioredoxin (U-Trx) concentrations and severity of children hydronephrosis caused by UPJO. MethodsThis study included 156 hydronephrosis children with unilateral UPJO and 80 healthy children. S-Trx and U-Trx concentrations were measured using enzyme-linked immunosorbent assay. U-Trx/creatinine (cr) ratio was calculated. ResultsS-Trx and U-Trx concentrations and U-Trx/cr ratio were significantly higher in hydronephrosis children than in healthy children. They were significantly correlated with split renal function, anterior–posterior diameter and Society for Fetal Urology classification, as well as were independently related to the split renal function <39.2%, anterior–posterior diameter>30mm and Society for Fetal Urology grade IV. Under receiver operating characteristic curves, U-Trx/cr ratio showed the higher predictive value compared to S-Trx and U-Trx concentrations. ConclusionIncreased S-Trx and U-Trx concentrations, especially U-Trx/cr ratio, are closely associated with the severity of children hydronephrosis, substantializing Trx as a promising biomarker for the progression of children hydronephrosis.

Prediction of Clinical Outcomes in Prenatal Hydronephrosis: Importance of Gravity Assisted Drainage

In infants with SFU (Society for Fetal Urology) grade 3-4 congenital hydronephrosis, 99mTc-mercaptoacetyltriglycine diuretic renography assesses differential function and drainage half-time. We routinely also include the percent of radiotracer drained after 30 minutes of diuresis as well as after 15minutes with the patient in the upright position. We investigated whether any 1or more of these parameters on initial diuretic renography predicts persistent or worsening drainage parameters. Infants 6 months or younger with grade 3-4 congenital hydronephrosis who presented between January 2009 and December 2014 were identified from billing data and included in analysis if they underwent at least 1baseline diuretic renography. Those with structural anomalies were excluded from study. Baseline and followup differential function, diuresis half-time, clearance at 30minutes and clearance with the patient upright were abstracted and comparisons were made between those with initially indeterminate diuresis half-time who underwent pyeloplasty vs those showing spontaneous improvement. A total of 74 patients (82 renal units) with presumed ureteropelvic junction obstruction met inclusion/exclusion criteria. All 10 renal units with initial diuresis half-time less than 5 minutes resolved spontaneously and all 25renal units with initial diuresis half-time greater than 75 minutes underwent pyeloplasty. Therefore, we defined the indeterminate group as the 47 renal units with initial half-time between 5 and 75 minutes. Of those 47 renal units with indeterminate initial diuresis half-time 23 (47%) underwent pyeloplasty and 25(53%) resolved spontaneously. Indications for pyeloplasty included worsening in 17 cases, persistent obstruction in 4 and urinary tract infection in 1. Among renal units with indeterminate drainage clearance while upright and clearance at 30 minutes were the only variables that differed significantly between surgical cases and those that resolved spontaneously. Radiotracer clearance with the patient upright and clearance at 30minutes are more predictive of surgical management than diuresis half-time or differential function for renal units with indeterminate drainage. They should be included in the standard assessment of ureteropelvic junction obstruction.