Postnatal management of antenatal hydronephrosis

Early post-operative outcomes of robot-assisted pyeloplasty in patients with unilateral ureteropelvic junction obstruction

INTRODUCTION

Ureteropelvic junction obstruction (UPJO) is a commonly encountered abnormality and it can lead to serious consequences such as renal dysplasia eventually resulting in loss of kidney. Hence, early diagnosis and timely management remains the cornerstone of the treatment. The most anticipated technique amongst modern day urologist is the robot-assisted laparoscopic pyeloplasty (RALP). The study aims to determine early post-operative outcomes of robot-assisted laparoscopic transperitoneal pyeloplasty procedure in patients presenting with unilateral ureteropelvic junction obstruction to establish the local perspective.

METHODOLOGY

This is a descriptive study involving patients with ureteropelvic junction obstruction in a tertiary care facility in Karachi; Sindh Institute of Urology and Transplant (SIUT). A total of 46 participants were recruited. Robot-assisted laparoscopic transperitoneal dismembered Hynes-Anderson pyeloplasty was performed by a single surgeon with over 3 years of experience in the presence of the researcher. Early postoperative outcome total operative time, length of hospital stay, console time and blood loss were noted by the researcher as per operational definition. Data were analyzed on SPSS Version 22.

RESULTS

Mean age in our study was 46.51 years with the standard deviation of ± 10.87. Whereas, mean length of hospital stay, total operative time, total blood loss, console time, pre-hemoglobin, posthemoglobin, height, weight and BMI in our study was 1.19 ± 0.40 days, 64.58 ± 17.59 min, 9.56 ± 6.13 ml, 30.17 ± 4.99 min, 12.66 ± 1.47 ml, 11.79 ± 1.93 ml, 165.62 ± 8.23 cm, 68.34 ± 8.23 kg and 24.85 ± 3.34 kg/m2, respectively.

CONCLUSION

Recent advancements in technology have yielded the latest RALP technique which has been proven significantly better than existing approaches and similar results are reported by this study demonstrating improvement in peri-operative and post-operative outcomes ultimately ameliorating the quality of life of patients with UPJO.

Determining Split Renal Function in Children With Ureteropelvic Junction Stenosis: Technetium-99m Mercaptoacetyltriglycine (Tc-99m MAG-3) or Technetium-99m Dimercaptosuccinic Acid (Tc-99m DMSA)?

Background Ureteropelvic junction stenosis (UPJS) is the most common cause of clinically significant antenatal hydronephrosis. We compared separate renal function results obtained using technetium-99m-mercaptoacetyltriglycine (Tc-99m MAG-3) and technetium-99m-dimercaptosuccinic acid (Tc-99m DMSA) in pediatric patients with UPJS to evaluate the adequacy of Tc-99m MAG-3 scintigraphy and the necessity of additional Tc-99m DMSA scintigraphy during follow-up. Methodology Patients diagnosed with hydronephrosis in the Pediatric Nephrology Department of Pamukkale University Faculty of Medicine over a period of 10 years (2012-2022) were evaluated retrospectively. Patients who had been diagnosed with UPJS and underwent both Tc-99m MAG-3 and Tc-99m DMSA scintigraphy during follow-up were included in the study. Technetium-99m-labeled MAG-3 and DMSA scans were re-evaluated for all patients by the Department of Nuclear Medicine. Results The study included 52 children with unilateral UPJS (12 girls and 40 boys) with a mean age of 6.34 ± 4.81 years (range: 2.97-9.79 years). Thirty-six patients (69.2%) were diagnosed antenatally. Differential renal function in Tc-99m DMSA was 46.94 ± 10.64 and in Tc-99m MAG-3 was 43.08 ± 11.18; the functions were lower in Tc-99m MAG-3, but the values were within normal limits for both groups (p=0.0001, z=-3.893). When differential renal functions were compared between Tc-99m DMSA and Tc-99m MAG-3 results, a statistically significant positive and strong correlation was found in the kidney with ureteropelvic junction obstruction (UPJO) (p=0.0001, r=0.752). When classifying the Tc-99m MAG-3 and Tc-99m DMSA results in the kidney with UPJO (supranormal, normal, low function) for the determination of differential renal functions, there was a consistency of 76%, and it was correlated (p=0.0001, k=0.456). While two patients had supranormal function and 13 patients had low function in Tc-99m MAG-3, five patients had supranormal function, and eight patients had low function in Tc-99m DMSA. Conclusions Some studies in the literature have reported that Tc-99m MAG-3 causes supranormal function measurements in patients with UPJS; our results showed that Tc-99m DMSA resulted in a higher rate of supranormal values for affected kidneys. We believe that Tc-99m DMSA should not be performed in addition to Tc-99m MAG-3 scintigraphy in the follow-up of every patient with UPJS but can be utilized in select cases, such as patients with surgical indications and those suspected before surgery.

Feasibility and Effectiveness of Repeat Laparoscopic Pyeloplasty for Recurrent Ureteropelvic Junction Obstruction in Pediatric Patients

Objective: To assess the outcomes of redo laparoscopic pyeloplasty (RLP) in pediatric patients with recurrent ureteropelvic junction obstruction (UPJO) in contrast to redo open pyeloplasty (ROP). In addition, evaluate the feasibility and efficacy of RLP as a treatment modality for recurrent UPJO in children. Materials and Methods: The data of 44 patients from March 2012 to March 2022, who underwent redo pyeloplasty, were retrospectively reviewed. In Group RLP, the children underwent RLP, whereas ROP was attempted in Group ROP. Demographics, clinical manifestations, surgical duration, hospitalization duration, complication rates, and treatment success were examined within the respective groups. Moreover, preoperative and postoperative measurements of anterior-posterior diameter of the renal pelvis (APD), preoperative assessment of differential renal function (DRF), and the percentage of improvement in DRF (PI-DRF) were subject to analysis. Results: The study included 28 patients who underwent RLP (Group RLP), and 16 patients who underwent ROP (Group ROP). In all cases, the Anderson-Hynes technique was employed. There was no significant difference between the two groups regarding age, body mass index, gender distribution, affected side, preoperative APD, postoperative APD, and preoperative DRF. In comparison to Group ROP, Group RLP exhibited a shorter hospitalization duration, a longer surgical procedure duration, and a higher percentage improvement in PI-DRF. The median follow-up period for Group RLP was 25 months, whereas it was 25.5 months for Group ROP. Notably, the success rates were similar between the two groups, with a success rate of 89.2% in RLP and 87.5% in ROP (p = 0.634). Conclusion: RLP has a comparable success rate to ROP and is a safe, effective, and feasible procedure for the treatment of failed pyeloplasty in children.

Automated Society of Fetal Urology (SFU) grading of hydronephrosis on ultrasound imaging using a convolutional neural network

INTRODUCTION

Grading of hydronephrosis severity on postnatal renal ultrasound guides management decisions in antenatal hydronephrosis (ANH). Multiple systems exist to help standardize hydronephrosis grading, yet poor inter-observer reliability persists. Machine learning methods may provide tools to improve the efficiency and accuracy of hydronephrosis grading.

OBJECTIVE

To develop an automated convolutional neural network (CNN) model to classify hydronephrosis on renal ultrasound imaging according to the Society of Fetal Urology (SFU) system as potential clinical adjunct.

STUDY DESIGN

A cross-sectional, single-institution cohort of postnatal renal ultrasounds with radiologist SFU grading from pediatric patients with and without hydronephrosis of stable severity was obtained. Imaging labels were used to automatedly select sagittal and transverse grey-scale renal images from all available studies from each patient. A VGG16 pre-trained ImageNet CNN model analyzed these preprocessed images. Three-fold stratified cross-validation was used to build and evaluate the model that was used to classify renal ultrasounds on a per patient basis into five classes based on the SFU system (normal, SFU I, SFU II, SFU III, or SFU IV). These predictions were compared to radiologist grading. Confusion matrices evaluated model performance. Gradient class activation mapping demonstrated imaging features driving model predictions.

RESULTS

We identified 710 patients with 4659 postnatal renal ultrasound series. Per radiologist grading, 183 were normal, 157 were SFU I, 132 were SFU II, 100 were SFU III, and 138 were SFU IV. The machine learning model predicted hydronephrosis grade with 82.0% (95% CI: 75-83%) overall accuracy and classified 97.6% (95% CI: 95-98%) of the patients correctly or within one grade of the radiologist grade. The model classified 92.3% (95% CI: 86-95%) normal, 73.2% (95% CI: 69-76%) SFU I, 73.5% (95% CI: 67-75%) SFU II, 79.0% (95% CI: 73-82%) SFU III, and 88.4% (95% CI: 85-92%) SFU IV patients accurately. Gradient class activation mapping demonstrated that the ultrasound appearance of the renal collecting system drove the model's predictions.

DISCUSSION

The CNN-based model classified hydronephrosis on renal ultrasounds automatically and accurately based on the expected imaging features in the SFU system. Compared to prior studies, the model functioned more automatically with greater accuracy. Limitations include the retrospective, relatively small cohort, and averaging across multiple imaging studies per patient.

CONCLUSIONS

An automated CNN-based system classified hydronephrosis on renal ultrasounds according to the SFU system with promising accuracy based on appropriate imaging features. These findings suggest a possible adjunctive role for machine learning systems in the grading of ANH.

Association between maternal use of spray formulations and offspring urological anomalies: The Japan Environment and Children's Study

OBJECTIVE

Concerns exist regarding the effects of maternal inhalation of household products on fetal health. This study aimed to clarify the impact of maternal exposure to household products, including spray formulations, on urological anomalies in offspring up to the age of 1 year.

METHODS

This study included data from 84 237 children from the Japan Environment and Children's Study, an ongoing nationwide cohort study. Using maternal self-report questionnaires, information on the use of organic solvents, waterproof sprays, insect-repellent sprays, insecticide sprays, and herbicides from implantation until the second or third trimester of pregnancy and data on urological anomalies were collected 1 year after delivery.

RESULTS

Urological anomalies occurred in 799 infants. Multivariate logistic regression analysis adjusted for maternal age, pregnancy body mass index, gestational diabetes, pre-existing maternal kidney disease, and preterm birth revealed no association between maternal exposure to organic solvents and the prevalence of offspring urological anomalies. Nevertheless, we observed significant associations between waterproof spray use during pregnancy and urological anomalies in boys (odds ratio [OR]: 1.28, 95% confidence interval [CI]: 1.03-1.59) and between the use of insecticide spray during pregnancy and urological anomalies in girls (OR: 1.48, 95% CI: 0.98-2.22). Sub-analysis revealed significant associations between waterproof spray use during pregnancy and vesicoureteral reflux in boys (OR: 2.14, 95% CI: 1.02-4.49) and between the use of insecticide spray during pregnancy and hydronephrosis in girls (OR: 2.23, 95% CI: 1.11-4.47).

CONCLUSION

Spray formulation use during pregnancy might increase the risk of urological anomalies in the offspring.

Sex differences in children operated with pyeloplasty for pelvoureteric junction obstruction

PURPOSE

Pelvoureteric junction obstruction (UPJO) is a common cause of hydronephrosis in children but no previous studies have evaluated differences between boys and girls operated with pyeloplasty. This study aimed to evaluate potential differences between sexes in children operated with pyeloplasty for PUJO in terms of presentation, surgery, and long-term results.

METHODS

Data was retrospectively collected from all children operated on with pyeloplasty between January 2002 and December 2020. Data contained several variables covering presentation, surgery, and long-term results.

RESULTS

In total, 194 patients were included of which 126 (64.9%) were boys. There were no significant differences in prenatal findings, pelvic dilation on ultrasound, function of the affected kidney, surgical method, obstruction type, resolution of hydronephrosis, or improvement of function. Boys presented with pain more often than girls (47.4 vs 25.0%, p < 0.01) while girls were more prone to infections preoperatively (17.2 vs 7.0%, p = 0.04). All nine patients requiring reoperation were boys (p = 0.03).

CONCLUSION

Girls with UPJO seem to experience infections as presenting symptoms more often than boys, while boys significantly more often present with pain. There is also a higher percentage of boys needing reoperation.

Pyeloplasty in Children with Ureteropelvic Junction Obstruction and Associated Kidney Anomalies: Can a Robotic Approach Make Surgery Easier?

BACKGROUND

Robot-assisted pyeloplasty is widely used in pediatric surgery because of its well-known advantages over open or laparoscopic surgery. The aim is to explore our experience and evaluate the achievements we have made.

METHODS

We evaluated patients undergoing robotic pyeloplasty from January 2016 to November 2021, including those who presented with a ureteropelvic junction obstruction associated with other anomalies of the kidney. The parameters examined were: age, weight, associated renal malformations, conversion rate, operative time, and intra- and postoperative complications.

RESULTS

Of 39 patients, 7 (20%) were included, of whom 5 (71%) were male and 2 (29%) were female. The mean age at surgery was 84 months (range 36-180 months), and the mean weight at surgery was 24.4 kg (range 11-40 kg). In five (71%) patients the ureteropelvic junction obstruction (UPJO) was left-sided and in two (29%) it was right-sided. In four (57%) cases, UPJO was associated with a horseshoe kidney, right-sided in one (25%) patient, and left-sided in the other three (75%). A 180° rotation of the kidney was present in one (14%) patient. Nephrolithiasis was present in two (29%) patients. The mean operative time was 160 min (range 140-240 min). The average bladder catheter dwell time was 1 day (range 2-3 days), while the average abdominal drainage dwell time was 2 days (range 2-4 days). The mean hospitalization time was 4 days (range 3-9 days). On average, after 45 days (range 30-65) the JJ ureteral stent was removed cystoscopically. No intraoperative complications were reported, while one case of persistent macrohematuria with anemia requiring blood transfusion occurred postoperatively.

CONCLUSIONS

Ureteropelvic junction obstruction might be associated with other congenital urinary tract anomalies such as a duplicated collecting system, horseshoe kidney, or pelvic kidney. These kinds of malformations can complicate surgery and require more attention and accuracy from the surgeon. Our experience shows that, with regards to the robotic learning curve required for pyeloplasty, the treatment of the ureteropelvic junction in these situations does not present insurmountable difficulties nor is burdened by complications. The application of robot-assisted surgery in pediatric urology makes difficult pyeloplasties easier.

Radiological and surgical correlation of pelviureteric junction obstruction in positional anomalies of the kidney in children

Pelviureteric junction obstruction, also known as ureteropelvic junction obstruction, is a congenital narrowing of the urinary excretory tract at the junction between the renal pelvis and the ureter and is a common cause of congenital pelvicalyceal dilatation. The outcome is variable, from spontaneous resolution to renal parenchymal function loss in cases of untreated high-grade obstruction. Abnormalities in renal ascent, rotation and vascularity can be associated with pelviureteric junction obstruction and easily overlooked radiologically. In this pictorial review, we explore the anatomical, radiological and surgical correlations of pelviureteric junction obstruction in the context of a normal kidney and a spectrum of renal abnormalities, including hyper-rotation (also known as renal malrotation), failed renal ascent, fusion anomalies and accessory crossing renal vessels. For each scenario, we provide technical tips on how to identify the altered anatomy at the first ultrasound assessment and correlation with scintigraphic, cross-sectional and postoperative imaging where appropriate. A detailed ultrasound protocol specifically to assess and characterise pelviureteric junction obstruction in paediatric patients is also offered.

Long non-coding RNA FABP5P3/miR-22 axis improves TGFβ1-induced fatty acid oxidation deregulation and fibrotic changes in proximal tubular epithelial cells of renal fibrosis

Severe hydronephrosis increases the risk of urinary tract infection and irretrievable renal fibrosis. While TGFβ1-mediated fibrotic changes in proximal tubular epithelial cells and fatty acid oxidation (FAO) deregulation contribute to renal fibrosis and hydronephrosis. Firstly, a few elements were analyzed in this paper, including differentially-expressed long non-coding RNAs (lncRNAs), and miRNAs correlated to CPT1A, RXRA, and NCOA1. This paper investigated TGFβ1 effects on lncRNA FABP5P3, CPT1A, RXRA, and NCOA1 expression and fibrotic changes in HK-2 cells and FABP5P3 overexpression effects on TGFβ1-induced changes. Moreover, this paper predicted and proved that miR-22 binding to lncRNA FABP5P3, 3'UTR of CPT1A, RXRA, and NCOA1 was validated. The dynamic effects of the FABP5P3/miR-22 axis on TGFβ1-induced changes were investigated. A Renal fibrosis model was established in unilateral ureteral obstruction (UUO) mice, and FABP5P3 effects were investigated. Eventually, this paper concluded that TGFβ1 inhibited lncRNA FABP5P3, CPT1A, RXRA, and NCOA1 expression, induced fibrotic changes in HK-2 cells, and induced metabolic reprogramming within HK-2 cells, especially lower FAO. FABP5P3 overexpression partially reversed TGFβ1-induced changes. miR-22 targeted lncRNA FABP5P3, CPT1A, RXRA, and NCOA1. LncRNA FABP5P3 counteracted miR-22 inhibition of CPT1A, NCOA1, and RXRA through competitive binding. TGFβ1 stimulation induced the activation of TGFβ/SMAD and JAG/Notch signaling pathways; Nocth2 knockdown reversed TGFβ1 suppression on lncRNA FABP5P3. FABP5P3 overexpression attenuated renal fibrosis in unilateral ureteral obstruction mice. The LncRNA FABP5P3/miR-22 axis might be a potent target for improving the FAO deregulation and fibrotic changes in proximal TECs under TGFβ1 stimulation.

Outcomes of intermediate-risk hydronephrosis in pediatric patients

PURPOSE

Hydronephrosis is a common antenatal diagnosis and is present in approximately 1-5% of pregnancies. The urinary tract dilation (UTD) classification system was introduced in 2014 and stratifies post-natal hydronephrosis risk into three groups: low-risk (P1), intermediate-risk (P2), and high-risk (P3). Recommendations for P3 hydronephrosis have been established, whereas those for P1 and P2 UTD are often left to the discretion of providers with P1 considered low-grade and less concerning significant pathology. Given the obscure nature of P2 hydronephrosis, we sought to determine the natural history and outcomes of pediatric patients with P2 hydronephrosis within a single institution.

MATERIALS AND METHODS

Children <18 years old diagnosed with hydronephrosis between January 2015 and December 2018 were identified by ICD-9 and ICD-10 codes. Patients with P1 hydronephrosis, P3 hydronephrosis, known vesicoureteral reflux, complex anomalies (ex. Posterior urethral valve), neurological impairments, neurogenic bladder secondary to spinal abnormalities, and <6 months of follow-up were excluded. The development of urinary tract infection (UTI; ≥100 000 CFU/mL of bacterial growth, UA > 10 WBCs/hpf with fever >38C), need for surgical intervention (impaired renal function, worsening hydronephrosis, and/or delayed drainage on diuretic renography), and stability of hydronephrosis were collected retrospectively.

RESULTS

Eighty-seven patients [105 renal units (RU)] were included. Twenty-six patients (30%) were female and 61 (70%) were male. Of the male patients, 30 (49%) of them were circumcised. The median age at initial evaluation was 1 month, and the median duration of follow-up was 13 months. Thirty-four (32%) RU had complete resolution, 24 (23%) improved to P1 hydronephrosis, 33 (31%) remained stable, and 14 (13%) progressed to P3 hydronephrosis. The median duration to resolution and improvement was 8.5 months and 5 months, respectively. Eleven (11%) RU required surgical intervention, 10 of which underwent pyeloplasty, with a median duration to intervention of 9 months. Fifty-five patients (63%) received antibiotic prophylaxis (amoxicillin or sulfamethoxazole-trimethoprim) for a median duration of 5 months. Nine patients (10%) developed a UTI, 3 of which were taking antibiotic prophylaxis at the time of infection.

CONCLUSIONS

Intermediate-risk hydronephrosis diagnosed in the pediatric population will either improve, resolve, or remain stable during 1-year follow-up in 87% of RU. Only 11% of RU required surgical intervention, and 19% of patients developed a UTI in the absence of antibiotic prophylaxis. These findings will assist with counseling parents concerning the importance of follow-up imaging and monitoring for UTI. However, the low risk of surgical intervention is encouraging and should be discussed with the children's caretakers.

The influence of interstitial cells of Cajal density in the outcomes of pyeloplasty in adults: A prospective analysis

Purpose:

To evaluate if the density of interstitial cells of Cajal (ICC) in the ureteropelvic junction (UPJ) influences the outcomes of pyeloplasty in adults.

Methods:

Twenty-three patients with the diagnosis of ureteropelvic junction obstruction (UPJO) that underwent laparoscopic dismembered pyeloplasty were included. ICC density was measured using immunohistochemistry reaction for c-KIT expression in the resected UPJ segment. Pyeloplasty outcome was evaluated by patient self-report pain, urinary outflow using DTPA renogram and hydronephrosis assessment using ultrasound (US) at 12 months of follow-up. A logistic regression analysis was performed to assess the association of pyeloplasty outcomes and ICC density.

Results:

Low, moderate, and high ICC density were present in 17.4%, 30.4%, and 52.2% of the patients, respectively. Complete pain resolution was observed in 100%, 85.7%, and 75% of patients with low, moderate and high ICC density, respectively ( p = 0.791). DTPA renogram improved in 75%, 85.7%, and 91.7% of patients with low, moderate and high ICC density, respectively ( p = 0.739). Hydronephrosis improved in 25%, 85.7%, and 91.7% of patients with low, moderate and high ICC density, respectively ( p = 0.032).

Conclusions:

Patients with high ICC density have a significant amelioration of hydronephrosis after pyeloplasty. However, ICC density is not associated with functional outcomes.

Timing of delivery in antenatal fetal hydronephrosis: a snap shot social media survery of obstetric and fetal medicine practice

OBJECTIVES

To identify when obstetricians would deliver a fetus with antenatal hydronephrosis and normal liquor. Designed as snap-shot survey. Setting: Survey Monkey link. Population/sample were obstetrics and fetal medicine consultants who received the survey link via closed professional forums on the North West Coast Maternity Clinical Network, Facebook, and publicly on Twitter.

METHODS

Survey link publicised as above, obstetric consultants were asked at what gestation would they deliver a fetus with antenatal hydronephrosis and normal liquor; and what criteria would they use to make that decision. Main outcome measures were number of years in practice, gestation at delivery, anteroposterior diameter (APD) of renal pelvis.

RESULTS

A total of 44/102 respondents (43%) would deliver prior to 40 weeks (median no. of years as consultant 10 years [IQR 5-17]) vs. those who would not (median years as consultant 5.5 [IQR 3-12]). Re APD threshold of delivery: 17 indicated delivery if the APD were 20 mm, 10 if it were 21-30 mm and 16 if it were >30 mm. Re gestation at which they would deliver: 13 indicated 37-38 weeks, 13 indicated 38-39 weeks and 17 indicated 39-40 weeks. Reasons selected for delivery before term were obstetric anxiety n=2, maternal request n=2, maternal anxiety n=2 and concern about fatal renal damage/renal damage n=34.

CONCLUSIONS

A surprising number of respondents would consider early delivery of a fetus with hydronephrosis and normal liquor despite the lack of evidence of benefit. The evidence supporting term delivery means that early term delivery is only indicated for obstetric reasons in this scenario.

Exacerbation of Congenital Hydronephrosis as the First Presentation of COVID-19 Infection in Children

Background. Congenital hydronephrosis is one of the most common abnormalities of the upper urinary tract, which can be exacerbated by a variety of intrinsic or extrinsic triggers. The urinary tract system is one of the major organs complicated by COVID-19 infection. Case Presentations. Here, we report five patients with an established diagnosis of congenital hydronephrosis, who presented with acute abdominal pain and fever and an abrupt increase in the anteroposterior pelvic diameter (APD). Patients had a previous stable course and were under regular follow-up with serial ultrasonographic studies. They underwent surgery or supportive treatment due to the later exacerbation of hydronephrosis. Based on the clinical and imaging findings, no plausible etiologies for these exacerbation episodes, including infection, nephrolithiasis, or abdominal masses, could be postulated. The common aspect in all these patients was the evidence of a COVID-19 infection. Conclusions. Infection with COVID-19 in children with antenatal hydronephrosis may exacerbate the degree of hydronephrosis and renal APD in ultrasonography, which itself may be mediated by the increase in inflammatory mediators.

Feasibility, safety and effectiveness of laparoscopic transperitoneal pyeloplasty in children: Ain Shams University early experience

Background/purpose

Laparoscopic pyeloplasty (LP) is now widely recognized as a minimally invasive alternative for the surgical repair of ureteropelvic junction obstruction (UPJO) in paediatrics. In this work, we aim to evaluate the feasibility, safety and effectiveness of LP in our early experience.

Patients and methods

Between April 2019 and April 2020, patients presented with indication for surgical repair of UPJO were offered laparoscopic transperitoneal Anderson-Hynes pyeloplasty. Demographic data, preoperative investigations, operative data and intra- or postoperative complications, as well as short and mid-term follow-ups were recorded.

Results

During the specified period, 13 patients underwent LP (8 girls and 5 boys) with a median age of 12 months (range from 5 to 150 months). There was no conversion to open approach with operative time ranging from 120 to 240 min (mean = 175 ± 34 min). No intra- or postoperative complications were encountered. One to 2 years postoperative follow-up was performed (median = 18 months) in 11 patients. One patient discontinued follow-up after 1 month and another after 6 months. Follow-up PAUS showed a reduction in the anteroposterior diameter of the renal pelvis in all cases. Postoperative diuretic renal scans (DTPA renography) were done for three patients with a persistent anteroposterior diameter of the renal pelvis greater than 20 mm which showed improvement in the washout. All patients had a good cosmetic outcome.

Conclusion

In our early experience in LP, we found the procedure a safe, feasible and effective technique in managing UPJO in children and infants with good cosmetic outcome.

Level of evidence

This is a case series study (level IV evidence).

Outcome analysis of immediate and delayed laparoscopic pyeloplasty in infants with severe ureteropelvic junction obstruction

OBJECTIVE

The treatment timing of ureteropelvic junction obstruction (UPJO) in infants remains controversial. This study aimed to compare the recovery effect of renal morphology of immediate and delayed laparoscopic pyeloplasty in infants with severe UPJO.

METHODS

The infants with severe UPJO-induced hydronephrosis who underwent laparoscopic pyeloplasty according to their age at the time of surgery [the immediate treatment (IT) group: ≤1 month of birth, the delayed treatment (LT) group: 3-6 months of birth] in our center between 2010 and 2019 were enrolled in this study. Ultrasonography was used to assess renal morphology, including anteroposterior diameter (APD) of a pelvic, parenchymal thickness (PT), polar length (PL), and Society of Fetal Urology (SFU) grade. Preoperative and postoperative renal morphological outcomes at 6, 12, and 24 months were measured and compared.

RESULTS

During this period, a total of 135 patients were assigned to receive either IT (n = 73) or LT (n = 62) and were included for analysis. There were no significant differences in renal morphology indices at baseline between groups of IT and LT. The APD, PT, and PL in both groups all recovered to certain degrees compared with those at baseline, however, the IT group recovered more significantly than the LT group. Despite there being no significant difference in SFU grade between the two groups before and after surgery, the reduction of SFU grade in the IT group was more significant than that in the LT group during the 6-, 12- and 24-month follow-up periods. The PL, SFU, and APD were greater in the IT group than in the LT group at 6, 12, and 24 months of follow-up. At 6 months PL was not significantly higher between the two groups, while the outcome was significantly different at 12 months and 24 months.

CONCLUSION

Immediate laparoscopic pyeloplasty for the infant with severe ureteropelvic junction obstruction is effective, and it can accelerate the recovery of renal morphological indices in infants with severe UPJO-induced hydronephrosis.

Functional Magnetic Resonance Urography in Ureteropelvic Junction Obstruction: Proposal for a Pediatric Quantitative Score

BACKGROUND

Ureteropelvic junction obstruction (UPJO) is one of the most frequent causes of congenital hydronephrosis. It is essential to distinguish UPJO which needs surgical treatment. fMRU combines high quality morphological details of the kidney and excretory pathways with functional data.

OBJECTIVE

This study aims to introduce a new radiological score based on fMRU findings to be able to differentiate surgical from non-surgical kidneys.

MATERIALS AND METHODS

We retrospectively selected patients with hydronephrosis due to UPJO who underwent fMRU (January 2009-June 2018). A multidisciplinary team identified a list of fMRU morpho-functional predictive variables to be included in the analysis. To evaluate the role of different independent variables in predicting the outcome, a multivariable logistic regression model has been performed; the outcome variable was the surgical intervention. For each predictive variable, Odds Ratio and 95% Confidence Intervals were calculated. The likelihood ratio test was used to assess the significance of the variables. Using the regression model, we assigned a numerical value to each predictive variable, rounding up the beta-coefficients. The cut-off value of the total score was obtained from the ROC curve analysis.

RESULTS

A total of 192 patients were enrolled, corresponding to 200 pathological kidneys. All of them underwent fMRU; 135 were surgically treated, while 65 underwent ultrasound or MRU follow-up. Predictive variables significantly associated with surgery resulted to be the urographic phase, the presence of abnormal vessels, and a baseline anterior-posterior pelvic diameter >23 mm. Beta coefficients of the logistic regression model were then converted in scores. The ROC curve of the score showed high sensitivity (84.3%) and specificity (81.3%) with a cut-off > 2.5.

CONCLUSIONS

We propose a new fMRU score able to identify surgical vs. non-surgical kidneys with UPJO.

Transurethral Retrograde Fishing the Double J Urethral Stent: A Tertiary Children Hospital's Experience With a New Technical Strategy

PURPOSE

The purpose of this study is to provide a new strategy for non-cystoscopic double J urethral stent (JJS) removal, the transurethral retrograde fishing the double J urethral stent (TURFJJS), that avoids general anesthesia in pediatric populations.

METHODS

We retrospectively reviewed the JJS removal records of patients having ureteropelvic junction obstruction (UPJO). We analyzed differences in the removal success rates, operation-related severe complications, total cost, duration, and parental satisfaction between TURFJJS and traditional cystoscopic double J urethral stent removal (CJJSR) procedures.

RESULTS

A total of 324 patients with UPJO were included in this study. CJJSR yielded a success rate of 100%. TURFJJS achieved a success rate of 94.3%. The TURFJJS was just an outpatient procedure, and its total cost was about 800 Chinese yuan (US$ 124). There were no severe JJS removal-related complications using TURFJJS. Parental satisfaction was 98.2 and 92.5% for the CJJSR and TURFJJS protocols, respectively.

CONCLUSION

TURFJJS is safe, effective, cost-effective, and well-tolerated in pediatric patients, minimizing or eliminating the need for general anesthesia, additional hospitalization, and waste of time. TURFJJS should be widely used in pediatric urology.

A comparative study between continuous and interrupted sutures in open pyeloplasty

BACKGROUND

Pelvi-ureteric junction obstruction (PUJO) is one of the common causes of obstructive uropathy dealt by urologists around the globe. The management of PUJO requires surgical intervention and pelvi-ureteral anastomosis is most time-consuming step in surgery and suturing plays a critical role for the good outcome of the surgery.

OBJECTIVE

To assess the outcomes of continuous or interrupted suturing in open pyeloplasties done for PUJ obstruction.

MATERIALS AND METHODS

This comparative study was conducted in the department of Urology in a tertiary care hospital of eastern India. A total of 60 patients with pelviureteric junction obstruction were included as per inclusion and exclusion criteria and divided into two groups depending upon whether continuous (Group A) or interrupted (Group B) suturing was done. Both groups were compared for mean operative time, mean suturing time, duration of post-operative drainage, mean drain output, post-operative hospital stay, postoperative GFR and improvement in GFR.

RESULTS

Out of 60 patients continuous and interrupted suturing was done in 30 patients in both arms. Out of 60 cases there were 46 (76.66%) males and 14 (23.33%) females with a M:F ratio of 1:0.30. The mean age in group A and group B was found to be 30.06 ± 8.28 and 27.63 ± 6.07, respectively. Mean operative time, mean suturing time, duration of post-operative drainage, mean drain output and postoperative hospital stay were found to be higher in interrupted suture group and the difference was found to be statistically highly significant (p < 0.0001). The complication rates and recurrence rates were found comparable in both the cases with no statistically significant difference (p > 0.05).

CONCLUSION

Continuous suturing technique for pyeloplasty is preferable as it is found to have a lower mean operative time, mean suturing time, duration of post-operative drainage, mean drain output and postoperative hospital stay.

Association between severity of prenatally diagnosed hydronephrosis and receipt of surgical intervention postnatally among patients seen at a fetal-maternal center

Background

Hydronephrosis (HN) is the most common abnormality detected on prenatal ultrasound. This study sought to stratify outcomes of patients by severity of prenatal HN with postnatal outcomes.

Methods

This was a retrospective review of patients referred to a tertiary care fetal-maternal clinic with diagnosis of prenatal HN from 2004 to 2019. HN severity was categorized as mild, moderate, or severe. Data were analyzed to determine the association between HN severity and surgical intervention. Decision for surgery was based on factors including history of multiple urinary tract infections, evidence of renal scarring, and/or reduced renal function. Surgery-free survival time was represented by the Kaplan–Meier method, and hazard ratios were calculated using the log-rank test.

Results

131 kidneys among 101 infants were prenatally diagnosed with hydronephrosis; 35.9% had mild HN, 29.0% had moderate HN, and 35.1% had severe HN. 8.5% of patients with mild HN, 26.3% of patients with moderate HN, and 65.2% of patients with severe HN required surgery. Patients with severe HN were 12.2 (95% CI 6.1–24.4; p < 0.001) times more likely to undergo surgery for HN than patients with mild HN and 2.9 (95% CI 1.5–5.3; p = 0.003) times more likely to undergo surgery than patients with moderate HN. Patients with moderate HN were 4.3 times more likely to require surgery than patients with mild HN (95% CI 1.5–12.9; p = 0.01). Median age at surgery was 11.8 months among patients with mild HN (IQR 11.7–14.1 months), 6.6 months among patients with moderate HN (IQR 4.2–16.4 months), and 5.4 months among patients with severe HN (3.7–12.4 months).

Conclusion

Among this cohort of referrals from a fetal-maternal clinic, severity of HN correlated with increased likelihood of surgical intervention. Continued assessment of patients with prenatal HN should be evaluated to best determine the role of the pediatric urologist in cases of prenatal HN.

Combined treatment of ureteropelvic junction obstruction and renal calculi with robot-assisted laparoscopic pyeloplasty and laser lithotripsy in children: Case report and non-systematic review of the literature

OBJECTIVE(S)

The incidence of urinary tract stone disease is steadily increasing in both adult and paediatric populations. This condition develops due to different factors: dietary or metabolic alterations, infection, and congenital anatomic malformations. Standard indications and treatments for children are analogous to the ones indicated for adults. Extracorporeal shock wave lithotripsy, ureterorenoscopy and percutaneous nephrolithotomy (PCNL) should be preferred to more invasive techniques. Moreover, the introduction of laparoscopic and robot-assisted laparoscopic approaches have improved surgical outcomes, lowering the bleeding risk with higher stone-free rates, even in complicated cases. Despite these well-known improvements, there are few reports regarding laparoscopic robot-assisted management for urinary tract stone disease in paediatric patients under the age of 10, especially with concomitant treatment of ureteropelvic junction obstruction and multiple calyceal stones.

PATIENT AND METHOD(S)

A 4-year-old child was referred for recurrent right abdominal flank pain, macroscopic haematuria and a previous history of urinary tract infections. A computed tomography of the abdomen showed right ureteropelvic junction obstruction associated with multiple unilateral stones located in the renal pelvis and in the interpolar renal calyces. Due to its complexity, we held a multidisciplinary meeting with paediatric surgeons and nephrologists to determine optimal treatment. As a result, a combined robot-assisted laparoscopic pyeloplasty (LP) and renal calculi holmium laser lithotripsy using a digital flexible ureteroscope through an abdominal robotic trocar was performed. No post-surgical complications were recorded, and the patient was discharged within 48 h following surgery. At subsequent regular follow-up examinations over a period of 24 months, no signs of recurrence were detected for both ureteropelvic junction obstruction and stone disease.

RESULT(S)

Robot-assisted LP with concomitant laser lithotripsy is a reasonable treatment option for designated young paediatric patients with challenging ureteropelvic junction obstruction complicated by urolithiasis, especially in cases where stones are not amenable with standard procedures.

Postnatal ultrasound follow-up in neonates with prenatal hydronephrosis

OBJECTIVES

Renal anomalies are the most common fetal abnormalities that occur during prenatal development, and are typically detected by observing hydronephrosis on fetal ultrasound imaging. Follow-up with post-natal ultrasound is important to detect clinically-important obstruction, because many of the pre-natal abnormalities resolve spontaneously. This study aimed to evaluate the postnatal hydronephrosis follow-up rate, and reasons for non follow-up in affected neonates.

METHODS

In this cross-sectional study all neonates born during a period of one year at Ayatollah Mousavi Hospital with hydronephrosis on fetal ultrasound imaging were recruited. All mothers were also given face-to-face information about fetal hydronephrosis and its postnatal outcomes, and follow-up with at least a postnatal ultrasound was recommended from the fourth day of their neonates' birth until the end of the fourth week. The neonates were subsequently observed for one month to determine the postnatal ultrasound follow-up rate and to reflect on diagnostic test results, reasons for failure to follow-up, as well as causes of hydronephrosis.

RESULTS

In this study, 71 cases (1.2%) out of 5,952 neonates had fetal hydronephrosis on prenatal ultrasound images. The postnatal ultrasound imaging showed kidney involvement in 18 neonates (25%), particularly in the left kidney (61.1%). Seven neonates had no follow-up at one month (10%). No significant relationship was found between lack of follow-up and the neonates' place of residence (p=0.42), maternal education (p=0.90), number of siblings (p=0.33), or gender (p=0.64).

CONCLUSIONS

Postnatal ultrasound follow-up rate in these neonates with a history of fetal hydronephrosis was incomplete even though parents had been provided with education and advice at their birth time. Accordingly, it is recommended to perform postnatal ultrasound once neonates are discharged from hospitals.

Febrile Urinary Tract Infections in Children with Primary Non-Refluxing Megaureter: A Systematic Review and Meta-Analysis

BACKGROUND

Knowledge of the baseline risk of febrile urinary tract infections in patients with primary non-refluxing megaureter can help clinicians to make informed decisions for offering continuous antibiotic prophylaxis.

OBJECTIVE

The primary objective of this systematic review was to determine the pooled prevalence of febrile urinary tract infections in patients with primary non-refluxing megaureter selected for primary non-surgical management independent of associated attributed risk factors at initial presentation in order to assess the value of continuous antibiotic prophylaxis.

METHODS

MEDLINE, EMBASE, and Cochrane Controlled Trials Register electronic databases were searched for eligible studies without language and time restriction. The systematic review was carried out following the recommendations of the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. (PROSPERO registration number CRD42018104752).

RESULTS

Of 25 871 records, 16 studies (n=749 patients) were eligible for inclusion. The overall pooled prevalence of febrile urinary tract infections in patients with primary non-refluxing megaureter was 14.35% (95% confidence interval: 8.8-22.6). The calculated number needed to treat for patients on continuous antibiotic prophylaxis to prevent one single febrile urinary tract infection over the course of 1-2 years would be 4.3.

CONCLUSION

Based on the current available evidence the use of continuous antibiotic prophylaxis for children with PM selected for primary non-surgical treatment should be taken into consideration, at least in patients with urinary outflow impairment, higher grade of ureteral dilatation, and for children in the first months of life.

Management of antenatal hydronephrosis

Antenatal hydronephrosis (AHN) is the most frequently detected abnormality by prenatal ultrasonography. Differential diagnosis of AHN includes a wide variety of congenital abnormalities of the kidney and urinary tract ranging from mild abnormalities such as transient or isolated AHN to more important ones as high-grade congenital vesicoureteral reflux or ureteropelvic junction obstruction. It is well known that the outcome depends on the underlying etiology. Various grading systems have been proposed for the classification of AHN on prenatal and postnatal ultrasonography. Mild isolated AHN represents up to 80% of cases, is considered to be benign, and majority of them resolve, stabilize, or improve during follow-up. Controversies exist regarding the diagnosis and management of some important and severe causes of AHN such as high-grade vesicoureteral reflux and ureteropelvic junction obstruction. Current approach is becoming increasingly conservative during diagnosis and follow-up of these patients with less imaging and close follow-up. However, there is still no consensus regarding the clinical significance, postnatal evaluation, and management of infants with AHN. The aim of this review is to discuss the controversies and provide an overview on the management of AHN.

Postnatal management of bilateral Grade 3-4 ureteropelvic junction obstruction

Introduction:

Bilateral hydronephrosis on prenatal ultrasound can be managed expectantly or with surgical intervention. The treatment strategies and outcomes are not clearly defined.

Methods:

We conducted a retrospectively audit of outcomes of management of prenatally detected severe bilateral ureteropelvic junction obstruction (UPJO) in our institution.Patients with bilateral Grade 3–4 hydronephrosis were included. Those with complications like rupture, underwent bilateral intervention within 4 weeks; in the remaining, unilateral pyeloplasty was performed at 4–12 weeks. The contralateral renal unit was re-evaluated at a later date for further improvement or deterioration. All the patients were followed up with ultrasonography and renogram at 3 months, 6 months, and 1-year post operatively. The case records were analyzed for the resolution of antero-posterior diameter (APD) or the improvement in single-kidney glomerular filtration rate (s-GFR) in the operated units.

Results:

Over 15 years, 28 patients (56 renal units) had bilateral UPJO (male-to-female ratio = 13:1). Twelve units underwent neonatal intervention to tackle the complications (6 bilateral pyeloplasty), 17 units underwent early pyeloplasty, and 15 underwent late pyeloplasty. Twelve of the twenty-two (54%) contralateral units, which were stented/observed, resolved spontaneously. Receiver operating characteristics analysis revealed that those with initial APD <25 mm and initial s-GFR >35 ml/m were more likely to improve during the observation. Ten of the forty-four operated units (22%) failed to show an improvement. Units with initial s-GFR <10 ml/m had poor chance of postoperative functional recovery.

Conclusions:

In neonates with bilateral UPJO, the worse affected kidney is operated first, as it still has the potential to recover. The contralateral milder UPJO unit is known to recover spontaneously following unilateral pyeloplasty. In those with bilateral Grade 4 UPJO and mass, bilateral pyeloplasty is feasible. Alternatively, unilateral pyeloplasty + contralateral cystoscopic retrograde stenting may prevent rupture or functional deterioration in the opposite kidney.

The different elements of the Urinary Tract Dilation (UTD) Classification System and their capacity to predict findings on mercaptoacetyltriglycine (MAG3) diuretic renography

INTRODUCTION

The UTD Classification System risk stratifies postnatal UTD into three groups: low risk (UTD P1), intermediate risk (UTD P2), and high risk (UTD P3). In the original consensus document, a functional scan is not recommended for UTD P1 and is left to the discretion of the clinician for UTD P2 and P3.

OBJECTIVE

This study aims to understand which patients with postnatal urinary tract dilation would benefit from a functional study. We investigated how different elements of the UTD classification system predict differential renal function (DRF) and diuretic half-life (T½) on MAG3 scan in infants undergoing evaluation for prenatally detected UTD.

STUDY DESIGN

This is a multicenter retrospective chart review of infants 6 months of age or younger evaluated for prenatal UTD, correlating their first MAG3 scan and first postnatal renal ultrasound (RUS). Multivariable logistic regression was used to find UTD elements predictive of DRF < 40% and/or T½ > 20 min.

RESULTS

A total of 517 patients met study criteria. Median age at time of RUS and MAG3 renal scan was 48 days (IGR 31-81) and 63 days (IQR 45-98), respectively. DRF < 40% was found in 6% of kidneys with UTD P2 and 35% of kidneys with UTD P3. T½ > 20 min was found in 31% of kidneys with UTD P2 and 79% of kidneys with UTD P3. An abnormal ureter (OR 2.7, 95% CI 1.2-6.0) and parenchymal thinning (OR 16, 95% CI 5.8-41.4) were significant at predicting DRF < 40%. Parenchymal thinning (OR 3.0, 95% CI 1.5-6.1) also predicted T½ > 20 min, as did each cm increase in the anterior-posterior renal pelvic diameter (APRPD) (OR 4.8, 95% CI 3.0-7.7).

DISCUSSION

The UTD system discriminates well and correlates with the likelihood of finding adverse features on diuretic renography. Patients in the UTD P3 high-risk category had a significantly higher incidence of decreased differential renal function and delayed drainage than those in UTD P1 and P2. Of the individual components of the UTD Classification system, the presence of parenchymal thinning was the most important factor in predicting both decreased differential renal function and delayed drainage.

CONCLUSION

Given the high incidence of poor function and delayed drainage seen in the UTD P3 group, we believe a functional study should be recommended in the evaluation of these patients. Our findings support leaving the performance of a functional study at the discretion of the physician for UTD P2.

Early pyeloplasty versus conservative management of severe ureteropelvic junction obstruction in asymptomatic infants

BACKGROUND

Ureteric-pelvic junction obstruction (UPJO) is the most common cause of antenatal and neonatal hydronephrosis and its management remains controversial. While conservative management is advocated for all, this strategy puts a quarter of these patients at risk for possibly irreversible renal damage.

AIM

In this study, we compare functional and anatomic outcomes in newborns and infants less than 1 year of age with high-grade unilateral UPJO, following early surgical pyeloplasty (ESP) versus conservative management (CM).

MATERIALS AND METHODS

This was a single center prospective interventional study. Infants referred to our tertiary care pediatric surgery clinic between September 2016 and September 2018 with UPJO were considered. To be included patients must have been less than 1 year old, lack of clinical symptoms, suffer from severe hydronephrosis as defined by Society for Fetal Urology (SFU) grades 3 or 4, and have affected kidney Split Renal Function (SRF) above 40%. Patients with bilateral disease, structural anomalies, or an abnormal voiding cystourethrogram (VCUG) were excluded. Anatomical and functional outcomes were measured and compared at 6 and 12 months.

RESULTS

Fifty-six patients were assigned to receive either ESP (n = 28) or CM (n = 28). At 6 months Cortical thickness, polar length, and SFU indices were significantly lower in the ESP group, while none of the outcomes were significantly different between the two groups at 12 months. Despite the two groups not being different at 12 months regarding differential renal function (DRF), there was a significant decrease of function in the CM group compared to baseline.

CONCLUSION

When considering treatment options for infants with high-grade UPJO, it appears that ESP hastens improvement of anatomic and functional indices, while CM may lead to a significant deterioration in renal function.

Antibiotic prophylaxis for prevention of urinary tract infections in the first year of life in children with vesicoureteral reflux diagnosed in the workup of antenatal hydronephrosis: a systematic review

BACKGROUND

Children with antenatal hydronephrosis (ANH) diagnosed with postnatal asymptomatic vesicoureteral reflux (VUR) are thought to be at higher risk of urinary tract infection (UTI). As such, continuous antibiotic prophylaxis (CAP) is empirically recommended until age of toilet training; however, there are limited data to support this. The objective of this systematic review was to summarize the existing data and compare UTI rates in infants with asymptomatic VUR on CAP during the first year of life, to those not on CAP. Secondary objectives were to determine associated risk factors with UTI development.

METHODS

A systematic search of all relevant studies and abstracts was conducted using 4 electronic databases by utilizing appropriate key words by an expert hospital librarian. Eligible studies included children with prenatal hydronephrosis, asymptomatic VUR with or without CAP, and reported on development of UTI in the first year.

RESULTS

Of 6903 citations screened, 18 were selected, giving a total population of 829 (69.4% male, median age 57 days) who met the inclusion criteria. Most studies were retrospective and of low-quality evidence. Overall, 15.4% of patients developed at least one breakthrough UTI and females had a higher risk of UTI (odds ratio (OR) 2.3, 95% CI 1.1-4.7). Comparison with children not taking CAP was not readily reported, and meta-analysis could not be completed.

CONCLUSIONS

Randomized controlled trials and standardized reporting of clinical variables are required to understand the protective effect of antibiotic prophylaxis in this cohort.

Pediatric congenital hydronephrosis (ureteropelvic junction obstruction): Medical management guide

The prevalence of asymptomatic hydronephrosis, now detected by ultrasonography, has increased. However, definitive management guidelines for the management of congenital hydronephrosis have not been established. The Japanese Society of Pediatric Urology created a "medical management guide" based on new findings for physicians practicing pediatric urology. We developed a medical management guide focused on congenital hydronephrosis caused by ureteropelvic junction obstruction. This medical management guide consists of the definition, pathophysiology, epidemiology, diagnosis, classification, treatment using a clinical management algorithm of hydronephrosis and the long-term course of the disease. The aim of hydronephrosis management is to determine whether surgery should be carried out to avoid renal dysfunction, as there is a possibility for improvement without intervention. Ultrasonography is essential to make treatment decisions. Management is determined by a comprehensive assessment, including the degree of hydronephrosis, anterior-posterior diameter of the renal pelvis and, if necessary, a nuclear medicine evaluation of the status of urine drainage and renal function.

Frequency of urinary tract infection in children with antenatal diagnosis of urinary tract dilatation

BACKGROUND

Neonates with congenital urinary tract dilatation (UTD) may have an increased risk of urinary tract infections (UTI). At present, the management of these patients is controversial and the utility of continuous antibiotic prophylaxis (CAP) remains uncertain as the literature presents contradicting evidence. The aim of this observational study was to assess UTI occurrence in children with prenatal diagnosis of urinary collecting system dilatation without antibiotic prophylaxis.

METHODS

Between June 2012 and August 2016, we evaluated the incidence of UTI and the clinical and ultrasonography evolution in 407 children with a prenatally diagnosed UTD. All subjects underwent two prenatal ultrasounds scans (USs) at 20 weeks and 30 weeks of gestation and within 1 month of birth. Patients with a confirmed diagnosis of UTD underwent US follow-up at 6, 12 and 24 months of life. According to the UTD classification system stratify risk, after birth UTD were classified into three groups: UTD-P1 (low risk group), UTD-P2 (intermediate risk group), and UTD-P3 (high risk group). Voiding cystourethrogram was performed in all patients who presented a UTI and in those with UTD-P3. No patient underwent CAP.

RESULTS

Postnatal US confirmed UTD in 278 out of 428 patients with the following rates: UTD-P1 (126), UTD-P2 (95) and UTD-P3 (57). During postnatal follow-up, 6.83% patients presented a UTI (19 out of 278). Eleven out of 19 had vesicoureteral reflux (VUR), and other four were diagnosed with obstructive uropathy and underwent surgical correction. Five patients presented a UTI reinfection.

CONCLUSION

The occurrence of UTI in patients with urinary collecting system dilatation was low. The recent literature reports an increased selection of multirestistant germs in patients with VUR exposed to CAP. This study constitutes a strong hint that routine continuous antibiotic prophylaxis could be avoided in patients with UTD.

Using Deep Learning Algorithms to Grade Hydronephrosis Severity: Toward a Clinical Adjunct

Grading hydronephrosis severity relies on subjective interpretation of renal ultrasound images. Deep learning is a data-driven algorithmic approach to classifying data, including images, presenting a promising option for grading hydronephrosis. The current study explored the potential of deep convolutional neural networks (CNN), a type of deep learning algorithm, to grade hydronephrosis ultrasound images according to the 5-point Society for Fetal Urology (SFU) classification system, and discusses its potential applications in developing decision and teaching aids for clinical practice. We developed a five-layer CNN to grade 2,420 sagittal hydronephrosis ultrasound images [191 SFU 0 (8%), 407 SFU I (17%), 666 SFU II (28%), 833 SFU III (34%), and 323 SFU IV (13%)], from 673 patients ranging from 0 to 116.29 months old (M age = 16.53, SD = 17.80). Five-way (all grades) and two-way classification problems [i.e., II vs. III, and low (0-II) vs. high (III-IV)] were explored. The CNN classified 94% (95% CI, 93-95%) of the images correctly or within one grade of the provided label in the five-way classification problem. Fifty-one percent of these images (95% CI, 49-53%) were correctly predicted, with an average weighted F1 score of 0.49 (95% CI, 0.47-0.51). The CNN achieved an average accuracy of 78% (95% CI, 75-82%) with an average weighted F1 of 0.78 (95% CI, 0.74-0.82) when classifying low vs. high grades, and an average accuracy of 71% (95% CI, 68-74%) with an average weighted F1 score of 0.71 (95% CI, 0.68-0.75) when discriminating between grades II vs. III. Our model performs well above chance level, and classifies almost all images either correctly or within one grade of the provided label. We have demonstrated the applicability of a CNN approach to hydronephrosis ultrasound image classification. Further investigation into a deep learning-based clinical adjunct for hydronephrosis is warranted.

Validation of "urinary tract dilation" classification system: Correlation between fetal hydronephrosis and postnatal urological abnormalities

Aim to illuminate the correlation between fetal hydronephrosis and postnatal urological abnormalities by a new classification system-"urinary tract dilation (UTD)" grade.Of 659 pregnancies screened by ultrasound, 34 cases were found with isolated fetal hydronephrosis, and enrolled in our study from 2017 to 2019. These 34 infants had been prospectively followed up to 6 months after birth by 3 times of urinary tract ultrasound. Hydronephrosis was graded in accordance with the UTD classification system.Among 34 infants with isolated fetal hydronephrosis. Twenty-four (70.6%) were classified as UTD A1 grade (mild hydronephrosis), and the other 10 (29.4%) were UTD A2-3 grade (moderate to severe hydronephrosis) by antenatal evaluation. After birth, all of the 24 infants (70.6%) with UTD A1 grade had normal ultrasonic findings of urinary tract; while the other 10 cases with UTD A2-3 grade had persistent abnormalities of urinary tract by postnatal assessment, sorted as UTD P1 grade (mild hydronephrosis) in 6 cases (17.6%), UTD P2 grade (moderate hydronephrosis) in 2 cases (5.9%) and UTD P3 grade (severe hydronephrosis) in 2 cases (5.9%). The most common postnatal urological abnormality of isolated fetal hydronephrosis was vesicoureteral reflux. During the follow-up period, 7 infants (20.6%) had urinary tract infection episodes and very few obtained positive cultures of the urine. Only 2 infants (5.9%) with the diagnosis of ureterovesical junction obstruction required surgery intervention, who were both classified as UTD P3 grade. None of the children with UTD P1 and P2 grades needed operation.The UTD classification system described the urinary tract both antenatally and postnatally, which could point out the correlation between fetal hydronephrosis and postnatal urological abnormalities. This new classification system is expected to be a good prognostic marker for fetal hydronephrosis.

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.

Significance of third trimester ultrasound in detecting congenital abnormalities of kidney and urinary tract-a prospective study

INTRODUCTION

Antenatal hydronephrosis is defined as dilatation of the renal pelvis with or without dilatation of calyces in the developing fetus. Although second trimester scan is more sensitive in detecting congenital abnormalities of kidney and urinary tract (CAKUT), it has been suggested that the third trimester scan is more predictive of postnatal outcome.

OBJECTIVES

This study aims to determine the incidence of antenatal hydronephrosis at our institution and the significance of third trimester scan in detecting CAKUT postnatally.

STUDY DESIGN

It is a prospective observational study. During the 3-year study period from June 2013 to May 2016, all cases of antenatal hydronephrosis, defined as renal pelvic diameter (RPD) ≥4 mm in the second trimester and ≥7 mm in the third trimester scan, diagnosed in the fetal medicine unit of our hospital, were included and were followed up postnatally for 6 months.

RESULTS

In the fetal medicine unit, 32,443 women were screened for anomalies, and hydronephrosis was detected in 269 cases. Incidence of antenatal hydronephrosis was observed to be 0.83% in our institution. In second trimester scan, of 80 cases with the left hydronephrosis, only 22 (27.5%) had postnatal CAKUT and of 70 cases with the right hydronephrosis, 18 (25.7%) had CAKUT. In the third trimester scan, it was observed that with RPD >10 mm, on the left side hydronephrosis, 87% had CAKUT on postnatal scan, and 85% with the right hydronephrosis had CAKUT.

CONCLUSION

Sixty percent cases of hydronephrosis detected in the second trimester scan resolve in utero. In the third trimester scan with RPD <10 mm, the possibility of postnatal CAKUT is 23%, whereas if RPD is > 10 mm, then the possibility of postnatal CAKUT is 86%.

Management of ureteropelvic junction obstruction in children-a roundtable discussion

The investigation, management and follow-up of paediatric ureteropelvic junction obstruction is not standardized. The Young Pediatric Urology Committee of the European Society of Pediatric Urology interviewed five experts in the field on various aspects of management and compared this with published literature.

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.

Congenital Anomalies of the Kidney and Urinary Tract: A Clinical Review

Purpose of review

This review highlights the most common congenital anomalies of the kidney and urinary tract (CAKUT) that are encountered in pediatric practices. CAKUT are the most common cause of prenatally diagnosed developmental malformations and encompass a spectrum of disorders impacting lower urinary tract development as well as kidney development and function. In pediatric and adolescent populations, developmental abnormalities are the leading cause of end-stage kidney disease. The goal of this review is to provide pediatric providers a framework for appropriate clinical management as well as highlight when referral to subspecialty care is needed.

Recent findings

While the exact etiologies of CAKUT are not completely defined, new evidence demonstrates that genetic and molecular changes impact embryonic kidney and urinary tract development. As a result, phenotypes and clinical outcomes may be affected.

Summary

Because pediatric providers provide front-line care to children and adolescents with developmental kidney and urinary tract anomalies, updated knowledge of CAKUT pathogenesis, embryology, clinical management, and patient outcomes is needed. This manuscript reviews CAKUT etiologies and essential diagnostic, prognostic, and management strategies.

Hydronephrosis After Pyeloplasty: "Will It Go Away?"

OBJECTIVE

To identify attributes of pediatric patients with hydronephrosis due to ureteropelvic junction obstruction and of their surgical encounters which are predictive of resolution of dilatation in order to provide more effective counseling about expected outcomes. This study was inspired by the suggestion in recent literature that greater than 20% improvement in anteroposterior diameter (APD) of the renal pelvis after pyeloplasty is indicative of resolution of obstruction. The remaining dilatation, however, is often distressing to caregivers, and there are no data to guide clinicians in counseling about its likelihood to resolve.

METHODS

We retrospectively reviewed children who underwent surgery at our institution for ureteropelvic junction obstruction between 1/01/2010 and 6/30/2017. APD of the pre- (preAPD) and postoperative (postAPD) renal pelves were documented. In children with more than 1 postoperative ultrasound, lastAPD was the measurement on their most recent study. Appropriate statistical tests examined the effects of clinical and surgical variables on hydronephrosis resolution.

RESULTS

PostAPD and lastAPD were obtained at medians of 3 months and 1.9 years after surgery, and were 0 cm in 12 of 105 (11.5%) and 9 of 65 (13.8%) patients, respectively. None of the variables analyzed significantly impacted complete resolution at either time point. Of those that did not resolve, 80.6% (75/93) showed greater than 20% improvement in APD; however, 3 of these children required reoperation due to secondary obstruction. In our study, no one with APD reduction greater than 43% required reintervention.

CONCLUSION

Complete resolution of hydronephrosis is uncommon and unpredictable. All caregivers should be counseled to expect dilatation to persist after obstruction is corrected.

Safe discharge parameters for patients with isolated antenatal hydronephrosis

INTRODUCTION

Antenatal hydronephrosis is a steady source of urology referrals since the era of routine fetal ultrasonography. Although most resolve, there are no guidelines for follow-up.

OBJECTIVE

Our goal is to define safe parameters with which patients can be discharged early and avoid unnecessary follow-up.

METHODS

We retrospectively reviewed all patients referred to a single children's referral hospital center for isolated antenetal hydronephrosis between 2010 and 2012. We looked at patients and renal units separately and divided the cohort into two groups for comparison. Our analysis endpoint is progression. That is, if the initial postnatal anterior-posterior diameter (APD) is less than 10 mm, progression occurs if the APD increases to 10 mm or above upon follow-up. Conversely, if the initial APD is 10 mm or more in at least one renal unit, progression occurs if the APD remains at 10 mm or above upon follow-up.

RESULTS

There majority of the 186 patients and 308 renal units included in the analysis, were classified in the APD less than 10 mm group. Most renal units in the APD of less than 10 mm group were of SFU grades 0-2 (92.1%) and most of the renal units in the APD of 10 mm or greater group were of SFU grades 3-4 (60%) (Table). Only 19 renal units (6.2%) underwent pyeloplasty, and they were all from the APD of 10 mm or greater group and classified as SFU grade 3-4. No renal unit with an APD of less than 10 mm, nor any with an APD of 10 mm or greater and a SFU grade 0-2 underwent pyeloplasty. More than half of the renal units' hydronephrosis resolved in the APD of 10 mm or greater group, in comparison with 96.1% of the APD of less than 10 mm group. On multivariate analysis, patients with an APD of 10 mm or greater were 7.76 times more likely to show progression (p = 0.0006).

CONCLUSION

An initial postnatal APD of 10 mm or greater, with a SFU grade 3-4, merits follow-up. However, all patients with an APD of less than 10 mm, especially when with a SFU grade 1-2, can be safely discharged as they are unlikely to experience complications.

Vhl deletion in renal epithelia causes HIF-1α-dependent, HIF-2α-independent angiogenesis and constitutive diuresis

One of the earliest requirements for the formation of a solid tumor is the establishment of an adequate blood supply. Clear cell renal cell carcinomas (ccRCC) are highly vascularized tumors in which the earliest genetic event is most commonly the biallelic inactivation of the VHL tumor suppressor gene, leading to constitutive activation of the HIF-1α and HIF-2α transcription factors, which are known angiogenic factors. However it remains unclear whether either or both HIF-1α or HIF-2α stabilization in normal renal epithelial cells are necessary or sufficient for alterations in blood vessel formation. We show that renal epithelium-specific deletion of Vhl in mice causes increased medullary vascularization and that this phenotype is completely rescued by Hif1a co-deletion, but not by co-deletion of Hif2a. A physiological consequence of changes in the blood vessels of the vasa recta in Vhl-deficient mice is a diabetes insipidus phenotype of excretion of large amounts of highly diluted urine. This constitutive diuresis is fully compensated by increased water consumption and mice do not show any signs of dehydration, renal failure or salt wasting and blood electrolyte levels remain unchanged. Co-deletion of Hif1a, but not Hif2a, with Vhl, fully restored kidney morphology and function, correlating with the rescue of the vasculature. We hypothesize that the increased medullary vasculature alters salt uptake from the renal interstitium, resulting in a disruption of the osmotic gradient and impaired urinary concentration. Taken together, our study characterizes a new mouse model for a form of diabetes insipidus and non-obstructive hydronephrosis and provides new insights into the physiological and pathophysiological effects of HIF-1α stabilization on the vasculature in the kidney.

The molecular biology of pelvi-ureteric junction obstruction

Over recent years routine ultrasound scanning has identified increasing numbers of neonates as having hydronephrosis and pelvi-ureteric junction obstruction (PUJO). This patient group presents a diagnostic and management challenge for paediatric nephrologists and urologists. In this review we consider the known molecular mechanisms underpinning PUJO and review the potential of utilising this information to develop novel therapeutics and diagnostic biomarkers to improve the care of children with this disorder.

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

PURPOSE

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.

MATERIALS AND METHODS

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.

RESULTS

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).

CONCLUSIONS

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.