Consensus on the Management of Posterior Urethral Valves from Antenatal Period to Puberty

Role of Urinary Biomarkers (Transforming Growth Factor β1, Neutrophil Gelatinase-Associated Lipocalin, and Cystatin C) as a Prognostic Factor of Renal Outcome in the Posterior Urethral Valve

Background

The urinary biomarker response precedes the appearance of any renal structural or functional derangement. Transforming growth factor-β1 (TGF-β1), neutrophil gelatinase associated lipocalin (NGAL), and Cystatin C (CysC) can act as the early prognostic markers in posterior urethral valve (PUV) patients.

Aim

To compare the urinary levels of TGF-β1, NGAL, and CysC between PUV cases and age matched controls and to correlate these with renal structural and functional parameters.

Materials and Methods

This prospective study included children with PUV diagnosed using the standard investigations and an equal number of age-matched controls with nonurological problems. For the study subjects, the urinary samples were collected at three different time points (pre- and postoperatively at 3 and 6 months), whereas for controls, only single-voided samples were studied. The urinary levels of TGF-β1, NGAL, and CysC were estimated by the standardized techniques using the ELISA kits. Statistical methods were used to drive the comparisons between cases and controls.

Results

Fifteen children with a median age of 10 (5-48) months were enrolled in each of the two groups. The mean uTGF-β1 in the case group was significantly higher at all three time points (43.20 ± 6.13 pg/ml, 43.33 ± 11.89 pg/ml and 40.71 ± 9.01 pg/ml) as compared to the control group (29.12 ± 8.31 pg/ml) (P ≤ 0.001). The median uNGAL in the case group was also higher (17.78 ng/ml, 2.35 ng/ml and 2.536 ng/ml) as compared to the control group (1.31 ng/ml). However, the difference was significant only preoperatively (P = 0.02). The median uCysC in case group was similarly higher (0.347 μg/ml, 0.439 μg/ml, and 0.382 μg/ml) than the control group (0.243 μg/ml) (P > 0.05). Serum creatinine in the case group (0.49 mg/dl) showed no significant rise above that of control (0.24 mg/dl). A cutoff value of uTGF-β1 = 36.55 pg/ml (P < 0.001), uNGAL = 0.879 ng/ml (P = 0.02), and uCysC = 0.25 μg/ml (P = 0.22) was found to be associated with renal damage in PUV. A significant correlation was found between uNGAL and S. creatinine at 3 months (r = 0.43, P = 0.017) and 6 months (r = 0.47, P = 0.08).

Conclusion

The elevated uTGF-β1, a decline in uNGAL and an increase in uCysC suggests ongoing inflammation, improvement in hydronephrosis and a prolonged proximal tubular dysfunction in PUV patients, respectively.

Post-obstructive diuresis after posterior urethral valve treatment in neonates: a retrospective cohort study

BACKGROUND

The management of posterior urethral valve (PUV) in neonates requires close monitoring in the intensive care unit because of the risk of post-obstructive diuresis (POD). Our aim was to describe the incidence and factors associated with POD in newborns treated for PUV.

METHODS

Retrospective analysis of the medical records of all neonates who underwent surgical intervention for PUV in our neonatal intensive care unit between January 2014 and April 2021.

RESULTS

Of the 40 patients included, 15 (37.5%) had POD defined by urine output > 6 ml.kg-1.h-1 during the first 24 h following urinary tract obstruction relief. At prenatal ultrasound examinations, oligohydramnios was more common in the group with POD than in the group without (53.3% vs. 8%, p = 0.002). Preterm birth was more frequent in neonates with POD (66.7% vs. 8%; p < 0.001). Median serum creatinine (212 [137-246] vs. 95 [77-125] µmol.l-1; p < 0.001) and urea (8.5 [5.2-12.2] vs. 4.1 [3.5-4.7] mmol.l-1; p < 0.001) concentrations on the day of obstruction relief were significantly higher in the group with POD than in the group without. After adjustment for prematurity, logistic regression models confirmed correlation between the occurrence of POD and the severity of the consequences of urethral obstruction (i.e., oligohydramnios and serum creatinine levels; ß = 2.90 [0.88; 5.36], p = 0.013 and ß = 0.014 [0.003; 0.031], p = 0.034, respectively).

CONCLUSIONS

In neonates, POD is common after the relief of PUV-related obstruction. Our findings may help to identify patients at highest risk. A higher resolution version of the Graphical abstract is available as Supplementary information.

Prenatal diagnosis and outcome of fetal urinomas in relation to the underlying etiology

OBJECTIVE

Evaluation of course and outcome of pregnancies with prenatally diagnosed fetal urinoma in a single center over a 20-year period.

METHODS

Retrospective study including all prenatally suspected or diagnosed fetal urinomas. Cases were analyzed by ultrasound findings during pregnancy, comparing urinomas caused by lower urinary tract obstruction (LUTO) and ureteropelvic or ureterovesical junction obstruction (UPJO/UVJO). Course of pregnancy and outcomes were compared according to the underlying etiology.

RESULTS

87 cases of fetal urinomas were identified between 2002 and 2022. The underlying etiology was LUTO in 56.3% and UPJO/UVJO in 43.7%. Complications mainly included oligo- or anhydramnios, thoracic hypoplasia as well as associated renal abnormalities. Postnatally, loss of function (LOF) in kidneys affected by urinomas was seen in 78.6% of children overall, but significantly more often in cases of UPJO/UVJO than in LUTO (86.2% vs. 70.2%, p < 0.05).

CONCLUSION

Association of prenatal urinoma and postnatal LOF of the affected kidney is high, especially in cases caused by UPJO/UVJO. In survivors with urinoma caused by UPJO/UVJO, the general prognosis is excellent if the contralateral kidney was normal. In survivors with urinomas caused by LUTO, long-term prognosis depends on postnatal renal and pulmonary function.

Long-term impact of commonly performed operations in pediatric urology on reproductive and sexual health

Introduction

Sexual dysfunction is highly prevalent among men of reproductive age. Clinical practice guidelines have been established to assist providers in identification and education of patients who are at increased risk for infertility and sexual dysfunction with certain congenital and acquired urogenital disorders. The authors sought to review the reproductive and sexual health implications of treating common childhood urological conditions with commonly performed surgical procedures.

Methods

To ensure the inclusion of influential and highly regarded research, we prioritized citations from the most-frequently cited articles on our respective review topics. Our inclusion criteria considered studies with substantial sample sizes and rigorously designed methodologies. Several topics were reviewed, including penile chordee, hypospadias, posterior urethral valves, varicoceles, undescended testicles, and testicular torsion.

Results

For chordee, surgical plication or corporal grafting may be employed. Erectile function remains unaltered post-surgery, while penile length may decrease after repair, which may be avoided using dermal grafts. Hypospadias repair hinges on severity and availability of the urethral plate. Those who underwent hypospadias repair report decreased penile length, but sexual satisfaction, libido, and semen quality are comparable to controls. Posterior urethral valves are usually treated with valve ablation. While valve ablation and bladder neck incision have not been found to affect ejaculatory function, high degree of concurrent renal dysfunction related to nephrogenic and bladder dysfunction may impact semen parameters and erectile function. Regarding varicocele, earlier management has been associated with better long-term fertility outcomes, and surgical intervention is advisable if there is observable testicular atrophy. Earlier repair of undescended testicle with orchiopexy has been found to improve fertility rates as well as decrease malignancy rates. Unilateral orchiectomy for testicular torsion without the ability for salvage has been shown to have decreased semen parameters but unaffected fertility rates.

Conclusion

Infertility and sexual dysfunction are multivariable entities, with etiologies both congenital and acquired. At the same time, many common pediatric urology surgeries are performed to correct anatomic pathology that may lead to reproductive dysfunction in adulthood. This review highlights the need for diagnosis and management of pediatric urologic conditions as these conditions may impact long-term sexual function post-operatively.

Mid-short-term risk factors for chronic renal failure in children with posterior urethral valve

OBJECTIVES

To analyze the mid-short-term risk factors for chronic renal failure (CRF) in children with posterior urethral valve (PUV) after valve ablation.

MATERIALS AND METHODS

A retrospective study of 143 patients with PUV who underwent operation was performed. Patients were divided into CRF group (n = 39) and non-CRF group (n = 104). Clinical data of both groups such as the first resection age, last resection age, number of operations, the maximal detrusor pressure (Pdet_max), and vesicoureteral reflux (VUR) were collected and analyzed.

RESULTS

The first resection age, last resection age, and the Pdet_max of patients in the CRF group were higher than those of patients in the non-CRF group (P < 0.05). Multiple regression analysis showed that the indicators related to chronic renal failure were last resection age (β = 1.034, P < 0.05) and Pdet_max (β = 1.068, P < 0.05). The cut-off value of last resection age was 35.5 months, Pdet_max was 41.65 cmH₂O. There was positive correlation of final blood creatinine with last resection age and Pdet_max.

CONCLUSION

The last resection age and Pdet_max are the risk factors of chronic renal failure in children with PUV. A Pdet_max of lower than 41.65 cmH₂O indicates a good prognosis of renal function in patients with PUV.

Tubular and glomerular biomarkers of renal tissue function in the urine of fetuses with posterior urethral valves

INTRODUCTION

Posterior urethral valve (PUV) is a congenital malformation characterized by a membranous structure located in the prostatic portion of the male posterior urethra that obstructs the urinary flow. Efforts have been made to determine the degree of impairment of fetal kidney function in this condition.

OBJECTIVE

This study aimed to measure the levels of urinary biomarkers of glomerular and tubular functions in fetuses with PUV and to compare with the levels of the same molecules in healthy male premature newborns.

STUDY DESIGN

Urine samples from 43 fetuses with PUVs were collected and compared with urine samples from 40 healthy male newborns of the same gestational age (controls). Tubular and glomerular biomarkers levels were measured in urine samples by MILLIPLEX® assay kits. Levels of the molecules were related to creatinine (Cr) measurements at same urine samples and expressed as pg/mg Cr. Results were analysed with Graphpad Prism version 7.0 and SPSS version 20.0.

RESULTS

Fetuses with PUV showed a significant reduction in urine levels of Epidermal Growth Factor (EGF), Calbindin, Osteoactivin, Molecule Renal Injury 1 (KIM-1 and Factor of trefoil 3 (TFF-3) when compared to controls. On the other hand, urine levels of cystatin C and renin were higher in PUV fetuses. The levels of molecules also differed according to urine osmolality and grade of hydronephrosis.

DISCUSSION

Some urinary excreted molecules may indicate kidney damage in several segments along the nephron, while others may exert important functions. Mechanical and immunological mechanisms related to PUV might significantly modulate the synthesis of cytokines related to glomerular and tubular physiology, leading to alterations in urinary concentrations of those molecules. These biomarkers can be used as future diagnostic and prognostic markers in clinical practice.

CONCLUSION

Early kidney structural and functional impairment influenced the synthesis of glomerular and tubular molecules related to kidney physiological processes in fetuses with PUV.

Does Early Upper Tract Diversion and Delayed Undiversion in Megaureters Secondary to Severe Posterior Urethral Valves Lead to Better Renal Outcomes?

Background

There are conflicting reports for the management of severe posterior urethral valve (PUV) after ablation. The primary objective was to assess the renal outcomes using the estimated glomerular filtration rate (eGFR) and secondary outcomes in severe PUVs who underwent early partially diverting reduction ureterostomy (PDRU) and a delayed undiversion protocol.

Materials and Methods

This 10-year retrospective study reviewed the records of 1094 boys with PUV, where severe PUV cases were treated with early PDRU (324 surgeries). We then analyzed those patients who completed the early diversion and delayed undiversion protocol. The long-term renal outcomes using eGFR and antero-posterior diameter (APD) were compared at various time points using appropriate statistical methods.

Results

Of the 171 severe PUV patients who underwent PDRU, 31 completed undiversion and 26 (47 renal units) were analyzed after exclusions. The mean age (standard deviation) at presentation was 1.46 ± 4.1 months. Thirty-two units were refluxing and 15 were nonrefluxing megaureters. PDRU was closed at a mean age of 3.9 years and had a mean duration of follow-up of 6.4 years. The mean eGFR increased from a minimum of 10.78 ± 10.25 at baseline and remained stable at 28.69 ± 18.89 after closure of both stoma. Similarly, mean APD decreased from 12.07 ± 6.79 at the diagnosis to 7.00 ± 6.20. Three patients (3 renal units) required revision of the stoma for stenosis and 1 patient had a parastomal hernia that was repaired at the time of undiversion.

Conclusions

In severe PUVs, early PDRU with delayed undiversion is a reliable surgical option that may ensure better renal outcomes in the long-term. Nonrefluxing renal units recover better than the refluxing. APD measurements also are shown to improve favorably.

Effects of oxybutynin in children with posterior urethral valves post fulguration: Report in a select cohort of children

Objectives:

Posterior urethral valves (PUV) is the commonest obstructive uropathy with varied consequences. Though valve fulguration is the treatment of choice, appropriate bladder management modifies outcome and includes rational use of anticholinergics. Here, we aim to evaluate the effects of oxybutynin on the bladder and urinary tract morphology and function. Concurrently, we document adverse effects encountered, patient compliance, and medication adherence.

Methods:

A retrospective study of children below 5 years of age (2012–2017) post fulguration and on oxybutynin for at least 6 months. Patient demographics, clinical features, renal ultrasound, micturating cystourethrogram, dimercaptosuccinic acid scan, adverse effects, and pill count for medication adherence were collated.

Results:

48 children below the age of 5 years were included, and 12 were excluded either due to the presence of concomitant problems or were not on oxybutynin. Of the 36, four were lost to follow-up and one had died due to an unrelated condition. Thus, a total of 31 children were analyzed. At follow-up, 28/31 patients were asymptomatic, two had daytime incontinence, and one had recurrent urinary tract infection. All patients except one have preserved renal function tests. On ultrasonography, hydroureteronephrosis worsened in only 1/25 children and two showed significant post void residues. The resolution of vesicoureteral reflux was noted in almost 50%. 4/31 renal units had progressive scars. Only two parents defaulted medication. Urodynamic study done in half of these children showed stable bladder pressures except in two.

Conclusion:

Oxybutynin therapy following adequate valve fulguration aids upper tracts preservation by stabilizing deranged bladder dynamics. The medication is well tolerated with minimal or no side effects.

Evaluation and fetal intervention in severe fetal hydronephrosis

PURPOSE OF REVIEW

Fetal hydronephrosis secondary to congenital anomalies of the kidney and urinary tract (CAKUT) can adversely affect neonates in the postnatal period with long-term consequences. A prenatal diagnosis of CAKUT can have an early fetal intervention to minimize these consequences. This review aims to provide an overview of the possible fetal intervention with severe hydronephrosis.

RECENT FINDINGS

Clinical course and outcomes of CAKUT are predicted based on biochemical markers and radiological findings. In spite of advancements and accurately diagnosing the severity of hydronephrosis, there are many controversies surround on selection of cases with antenatal hydronephrosis (ANH) that will benefit from fetal intervention. Despite better diagnosis and techniques fetal intervention is limited to mainly lower urinary tract obstruction patients to improve amniotic fluid volume and assist in lung development.

SUMMARY

ANH can potentially detect the severity of congenital renal anomalies but unable to recognize a specific disease. A multidisciplinary approach is required to diagnose and properly stage cases of severe CAKUT and potential surgical intervention can be considered.

An Unusual Urological Manifestation of Williams-Beuren Syndrome: Posterior Urethral Valve

Williams-Beuren syndrome (WBS) is a genetic, well-defined, rare, neurodevelopmental disorder characterized by intellectual disability, congenital heart defects, abnormal facial features, and growth, endocrine, and genitourinary abnormalities. The genitourinary abnormalities in WBS frequently include congenital structural renal defects, vesicoureteral reflux, nephrocalcinosis, proteinuria, and chronic renal insufficiency. Treatment of patients with posterior urethral valve (PUV) remains a clinical challenge, requiring long-term management from early infancy into adulthood in order to avoid progressive renal insufficiency. To my knowledge, this is the first worldwide case of WBS with PUV in a 12-year-old boy. Due to the delayed detection of the defect, chronic renal disease occurred as a risk for him. This case demonstrates the importance of early diagnosis of genitourinary anomalies such as PUV to prevent chronic renal disease in boys and especially in patients with WBS.

Role of Urinary Transforming Growth Factor Beta-B1 and Monocyte Chemotactic Protein-1 as Prognostic Biomarkers in Posterior Urethral Valve

Background:

Posterior Urethral Valves (PUV) are the most common cause of congenital LUT obstruction in males. Biomarkers of glomerular or tubular injury may be of particular value in predicting the need for surgical intervention or in tracing progression of chronic kidney disease. Measurement of biomarker in urine is relatively easy.

Aim:

To evaluate the changes in values of urinary Transforming Growth Factor Beta 1(TGF-B1) and Monocyte Chemotactic Protein (MCP-1) before and after valve ablation and its prognostic value in Posterior urethral valve.

Material and Method:

This prospective study was conducted from September 2016 to August 2018. The study group included 20 consecutive male babies with the diagnosis of PUV treated and followed up versus equal numbers of age matched control without any renal or urinary tract disease. Pre-operative urine samples were collected in Operative room. Cystoscopy and valve ablation was done. Follow up was done clinically by urinary stream and radiologically with VCUG. Follow-up was planned at 1 month, 3 months and 6 months following cystoscopic valve ablation. All collected urine samples were centrifuged at 10,000 rpm for 20 minutes. Supernatant was collected and two divided aliquots were stored at -200c to be thawed on the day of assay. Optical density of each well was recorded at 450 nm and 540 nm A p-value of <0.05 was considered to be statistically significant.

Result and Discussion:

Out of 20 cases of PUV, 14 (70%) cases were 1st born males of their family. The median age at the time of valve ablation in PUV cases was 2.5 (1.20-3.87) years.. Most common symptoms are fever and UTI. The preoperative median serum creatinine level was 1.65 mg/dl(1.22-2.42) pre-ablation, and fall significantly after ablation. Median eGFR level (calculated) was 25.635 (16.38-35.40) and after 6 months was 71.490 (45.44-96.93). Preoperative median MCP1 in PUV cases was 147.2 (82.8-512.5) and significant difference was also found in 1st, 3rd and 6th months after surgery (p<0.001, p=0.004 and p=0.002).Preoperative median TGF-B1 level was 197.8 pg/ml (79.9-386.4). There was no statistically significant change in TGF-B1 level at preoperative to 1 month and preop to 3 months after surgery but at 6 months after surgery the median TGF-B1 level significantly decreased as compared with preoperative TGF-B1 level.

Conclusion:

TGF β1 and MCP1 can be considered as prognostic urinary biomarkers in patients of PUV and can be used to specify and counsel patient's attendant regarding possibility of ESRD and need for further intervention.

Insight into Posterior Urethral Valve from Our Experience: Paradigm Appended to Abate Renal Failure

Objective:

The objective of the study was to share our experience of management of posterior urethral valve (PUV) and to suggest a paradigm to impede upstaging of chronic kidney disease (CKD) and prevent end-stage renal failure (ESRF).

Patients and Methods:

We have treated 332 patient of PUV from March 2005 to April 2016, Of which 272 case records had adequate data to be analyzed. The mean age was 2.48 years (range: 1 day–18 years). We did primary fulguration in 231 patients, of which five patients needed bilateral ureterostomy for obstinate high creatinine level. The remaining 36 patients had primary fulguration done elsewhere.

Results:

The mean duration of follow-up was 7.8 years (range 3–14 years). In the end of this study, 10 patients had down staging in CKD, 36 patients had up staging in CKD, and 9 patients ended in ESRF (3.8%).

Conclusions:

Detection of deterioration of renal function with creatinine clearance along with identifying the causes of deterioration and necessary interventions would help to arrest upstaging of CKD otherwise that might end in ESRF. From this study and reviewing the literature, we presume that the rhabdosphincter spasm underneath actually renders bladder outlet obstruction, and cusps of PUV, particularly in neonates, amplify the obstruction, following that bladder outlet obstruction cascades detrusor hypertrophy, bladder neck hypertrophy/obstructions, and ureterovesical junction obstruction/reflux, causing gradual damage to the bladder and upper tract and deterioration of renal function as a consequence.

Can the posterior:anterior urethral ratio on voiding cystourethrogram be used as a reliable predictor of successful posterior urethral valve ablation in male children?

Background

The role of the voiding cystourethrogram (VCUG) in the follow-up of children with posterior urethral valves (PUVs) post-ablation has been considered a standard practice. The urethral ratio and gradient of change have proven to be useful.

Objectives

We aimed to review the role of the ‘ideal’ ratio on predicting residual PUV post-ablation.

Methods

A systematic review of the PubMed, SCOPUS and Web of Science databases was performed (April 2019). The search terms included ‘Urethral Ratio and Posterior urethral valve ablation’. All cited reference lists were further evaluated for additional inclusive studies.

Results

Eleven studies were identified, of which nine were relevant to the topic. Case reports, comments and adult and animal studies were excluded, leaving four studies for critical review. In total, 338 patients were assessed. The control group consisted of 167 age-matched, male children. Study regions included India and Australia. The ages ranged from 15 days to 3.4 years. Ablation methods included the use of a resectoscope with cutting diathermy, cold knife or Bugbee electrode. The mean urethral ratios in the control group ranged from 1.04 to 1.73. The suggested predictive urethral cut-off ratios recommended include 2.2 (p = 0.001), 2.5–3 and 3.5.

Conclusion

Although the precise cut-off ratio could not be clearly defined in this review, a urethral ratio less than a range of 2.2–3.5 has proven to be a beneficial predictor of ablation success and should thus be incorporated into standard VCUG reporting templates in the follow-up of PUVs in male children in resource-limited settings.