Cases Of Posterior Urethral Valves Research Articles

Valve of the Posterior Urethra in Girls: A Case Report from the Gavardo Hospital in Mali

This is a prospective study of a single case of posterior urethral valve in a 2-year-old girl in the Gabriel Toure Urology Department. Posterior urethral valves (PUV) are congenital obstructive membranous folds that represent the main cause of congenital subvesical obstruction and dysuria in children and infants [1]. Their aetiology remains unknown, and is probably related to poor positioning of the orifices of the Wolffian ducts leading into the urethra [2]. Abdominal and pelvic ultrasound combined with Uroscanner revealed bilateral ureterohydronephrosis with repercussions on the upper urinary tract. Suprapubic cystography showed stenosis of the membranous urethra with dilatation of the posterior urethra upstream of the valve and diverticular bladder. The procedure consisted of ureterovesical reimplantation plus intubation via an external ureteral drain, which was removed at10 postoperatively, and stripping followed by ureterovesical catheterisation. The post-operative course was straightforward.

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.

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. 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. 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. 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). 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.

Comparing Estimated and Measured Glomerular Filtration Rate in Children with Posterior Urethral Valve.

Posterior urethral valve (PUV) is obstructive uropathy that may lead to chronic kidney disease (CKD) and end-stage renal disease (ESRD) in children. Glomerular filtration rate (GFR) measurement remains the gold standard for renal function measurement. However, due to its less availability and cumbersome, it is not commonly used, and GFR is estimated utilizing various endogenous filtration markers. This study includes pediatric patients with PUV. We aimed to compare the measured GFR (mGFR) with various creatinine-based estimated GFR methods (eGFR). A single-center retrospective study included 62 treated cases of PUV, postvalve fulguration. The mGFR measured by 99mTc-diethylenetriaminepentaacetate in vitro method and compared with eight eGFR (Schwartz, Cockcroft-Gault [CG], Counahan-Barratt [CB], CKD Epidemiology Collaboration [CKD-EPI], full-age spectrum [FAS] age, FAS height (FAS Ht), Schwartz-Lyon [SL], and Ht independent). Patients were subdivided into different CKD grades and compared with various eGFR. PUV is a common cause of CKD in children and needs special consideration as there is growth retardation associated with it. It decreases creatinine production and thus fallacies in eGFR measurement. There is a requisite to identify and closely monitor the subset of patients with baseline decreased renal function and therefore at risk of developing ESRD. A total of 62 patients were included. Mean age and serum creatinine levels were 8.02 ± 5.53 years and 1.15 ± 0.95 mg/dl (range: 0.4-4.5), respectively. The mean mGFR was 61.6 ± 31.80 mL/min/1.73 m2 and a positive variable correlation was 0.46-0.77 between mGFR and eGFR. Based on mGFR, there were 14 (22.6%), 21 (33.8%), 13 (20.9%), 9 (14.5%), and 5 (8.1%) patients in Grades I-V, respectively. The correct classification of the CKD grades was noted in 25 (40.3%), 16 (25.8%), 32 (51.6%), 16 (25.8%), 25 (40.3%), 27 (43.5%), 26 (41.9%), and 28 (45.2%) patients by Schwartz, CG, CB, CKD-EPI, FAS age, FAS Ht, SL, and Ht-independent equation. The eGFR overestimates GFR at the lower level and underestimates at higher levels. Our results confirm the considerable limitations of various creatinine-based clearance methods for estimating actual GFR. The creatinine clearance-based eGFR should not replace the measurement of the GFR. An initial measure of the mGFR followed by serial follow-up with the eGFR equation may be done. The most accurate eGFR equations are CB for Grade II, SL or Ht independent for Grade III, FAS age for Grade IV, and SL for Grade V CKD.

Frequency of posterior urethral valves in newborns with hydronephrosis in nicu and early outcomes: A tertiary center experience

Aim: To assess the frequency of posterior urethral valves (PUV) in male infants diagnosed with hydronephrosis in the neonatal intensive care unit (NICU) and the early outcomes. Materials and Methods: The study included male patients who had been diagnosed with hydronephrosis in the antenatal or postnatal period in our NICU between 2017 and 2020. We investigated antenatal hydronephrosis detection statuses, birth histories, ultrasonographic findings, and the lowest creatinine values detected during the NICU treatment of PUV-diagnosed patients. Results: A total of 73 infants had hydronephrosis and 20.5% of the patients (n=15) had PUV, and 26.6% (n=4) of the PUV patients had below 5 mm renal pelvic diameters. These patients were diagnosed with clinical suspicion (interrupted urination, decreased diuresis, or globe vesicle). In PUV-diagnosed patients, dysplastic kidneys and increased renal echogenicity are associated with poor outcomes (death or dialysis need). Conclusion: Hydronephrosis finding in ultrasonography may not be sufficient, so complete clinical evaluation is needed in newborns not to miss PUV cases.

Diverse ancestry whole-genome sequencing association study identifies TBX5 and PTK7 as susceptibility genes for posterior urethral valves.

Posterior urethral valves (PUV) are the commonest cause of end-stage renal disease in children, but the genetic architecture of this rare disorder remains unknown. We performed a sequencing-based genome-wide association study (seqGWAS) in 132 unrelated male PUV cases and 23,727 controls of diverse ancestry, identifying statistically significant associations with common variants at 12q24.21 (p=7.8 × 10-12; OR 0.4) and rare variants at 6p21.1 (p=2.0 × 10-8; OR 7.2), that were replicated in an independent European cohort of 395 cases and 4151 controls. Fine mapping and functional genomic data mapped these loci to the transcription factor TBX5 and planar cell polarity gene PTK7, respectively, the encoded proteins of which were detected in the developing urinary tract of human embryos. We also observed enrichment of rare structural variation intersecting with candidate cis-regulatory elements, particularly inversions predicted to affect chromatin looping (p=3.1 × 10-5). These findings represent the first robust genetic associations of PUV, providing novel insights into the underlying biology of this poorly understood disorder and demonstrate how a diverse ancestry seqGWAS can be used for disease locus discovery in a rare disease.

Imaging and clinical findings in late presenting posterior urethral valves in a resource-constrained economy

Posterior Urethral Valve (PUV) is the commonest cause of lower urinary tract obstruction in male children. Late presentation with delayed diagnosis is common in our setting. This study aims to review the clinical, biochemical, imaging findings and parental factors in late-presenting posterior urethral valves. A retrospective analysis of patients with PUVs seen at UNTH from 2011-2019 was done. Patients who presented at or later than six months of age were considered late presenters and were studied. Patients’ sociodemographic characteristics, antenatal diagnosis, clinical features, and imaging findings at presentation were retrieved. Data analysis was done using SPSS version 22. Statistical significance was set at a p-value&lt;0.05. Twenty-four cases of PUV with complete clinical data were studied. Mean age 3.3 (SD±2.1) years had a positive association with maternal educational level (p≤0.001). Nineteen (72.9%) had antenatal care, 4 (16.7%) had prenatal Ultrasonography (USS), and were part of those who had antenatal care. None had a prenatal diagnosis. Prenatal USS was associated with higher paternal education (p=0.03). The most common clinical symptom and finding respectively were straining to pass urine 23 (95.8%) and palpable bladder 23 (95.8%). The common electrolyte derangements included hyperkalemia (50%), raised serum urea (70.8%) while postnatal hydronephrosis 23 (95.8%) was the main ultrasound and MCUG findings. Late presentation is common with urinary dysfunction and azotemia. Improved antenatal care including late trimester ultrasound and parental health education will enhance prenatal diagnosis and early presentation.

Clinical profile of children with posterior urethral valve at Tertiary Care Center.

Background & Objective:Posterior Urethral Valves (PUV) are common cause of congenital obstructive uropathy in boys and may be associated with urinary tract infection(UTI) and chronic kidney disease(CKD) if not managed timely. The objective of our study was to determine the clinical profile of children with PUV.Methods:This is a descriptive case series comprising of 30 children aged 1-5 years, diagnosed and managed as PUV over six months, conducted at the Department of Pediatric Nephrology, National Institute of Child Health, Karachi. Patients were followed for 12 weeks and the outcome was assessed in terms of recovery, UTI, urinary incontinence and CKD. Descriptive statics were used for data analysis.Results:Thirty cases of PUV were managed during study period. Clinical presentations were poor urinary stream (83%), fever (73%), signs and symptom suggesting UTI (96.6%), pallor (73.3%), acute kidney injury (37%)and urinary retention (13%). UTI was confirmed in 73.3 % and E.Coli was the most common pathogen. Ultrasonography showed bilateral hydronephrosis/hydroureter in 80% and micturating cystourethrogram demonstrated vesicoureteral reflux in 86.66% cases. All patients received intravenous hydration (97%), urinary decompression, and antibiotics. Meropenem was the most commonly used. Packed cell transfusion and peritoneal dialysis was done in 73.33% and 13.3% respectively. Cystoscopic valve fulguration was done in 86.66% and vesicostomy in 13.3%. On short-term follow-up, 60% recovered,16.66% experienced UTI and remained incontinent whereas 23.33% had CKD.Conclusion:Our study showed a high frequency of UTI and AKI. E. coli was most common pathogen. Despite valve fulgration, significant patients had CKD.

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.

Urinoma

Severe urinary tract obstruction, particularly bladder outlet obstruction, can lead to extravasation of urine and development of urinary ascites or a urinoma. These occur as complications of urinary tract obstruction either through rupture of the bladder or a calyceal fornix or tear in the renal parenchyma, which can be identified in the second or third trimester of labor. In one study, urinomas or urinary ascites were reported in 20% of cases of posterior urethral valves.1

Prenatally diagnosed lower urinary tract obstruction: A 15-year experience at two tertiary centers in Japan.

To examine the outcomes of prenatally diagnosed lower urinary tract obstruction (LUTO) with current management using vesicoamniotic shunting (VAS). A retrospective study of prenatally diagnosed LUTO before 26 weeks of gestation at two tertiary centers in Japan between March 2002 and September 2017. LUTO was diagnosed by ultrasound demonstration of an enlarged fetal bladder associated with hydronephrosis and/or hydroureters. VAS was offered for fetuses with LUTO at ≤26 weeks of gestational age, in the presence of oligohydramnios or decreasing amniotic fluid and a favorable fetal urinary analysis. Among 87 fetuses with LUTO, 46 (53%) were terminated before 22 weeks of gestation. Eight cases (9%) underwent VAS and one underwent fetoscopic urethrotomy. The live birth rates in the VAS and expectant groups were 100% (8/8) and 56% (18/32), respectively (p= 0.034), and the survival rates at 6months old with a normal renal function were 38% (3/8) and 16% (5/32), respectively (p= 0.608). The etiology varied with six cases of associated anomalies among 23 diagnosed cases. Among the nine cases of posterior urethral valve (PUV), only one fetus underwent VAS at 25 weeks of gestation, ultimately surviving with mild renal dysfunction. Among the other eight cases of PUV that were managed expectantly, two died, and only one of the six survivors showed a normal renal function. More than half of the prenatally diagnosed LUTO cases were terminated. VAS seemed effective for achieving a perinatal survival, regardless of etiology. The outcomes were poor in cases of expectantly managed PUV.

CDH12 as a Candidate Gene for Kidney Injury in Posterior Urethral Valve Cases: A Genome-wide Association Study Among Patients with Obstructive Uropathies

BackgroundPosterior urethral valves (PUVs) and ureteropelvic junction obstruction (UPJO) are congenital obstructive uropathies that may impair kidney development. ObjectiveTo identify genetic variants associated with kidney injury in patients with obstructive uropathy. Design, setting, and participantsWe included 487 patients born in 1981 or later who underwent pyeloplasty or valve resection before 18 yr of age in the discovery phase, 102 PUV patients in a first replication phase, and 102 in a second replication phase. Outcome measurements and statistical analysisSigns of kidney injury were defined as dialysis, nephrectomy, kidney transplantation, estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2, high blood pressure, antihypertensive medication use, proteinuria, and/or one kidney functioning at <45%. We used χ2 tests to calculate p values and odds ratios for >600 000 single-nucleotide polymorphisms (SNPs) in the discovery sample comparing patients with and without signs of kidney injury within 5 yr after surgery. We performed stratified analyses for PUV and UPJO and Kaplan-Meier and Cox regression analyses in the discovery and two replication samples for the associated SNPs, and RNA and protein expression analyses for the associated gene in fetal tissues. Results and limitationsDespite the small and nonhomogeneous sample, we observed suggestive associations for six SNPs in three loci, of which rs6874819 in the CDH12 gene was the most clear (p = 7.5 × 10–7). This SNP also seemed to be associated with time to kidney injury in the PUV discovery and replication samples. RNA expression analyses showed clear CDH12 expression in fetal kidneys, which was confirmed by protein immunolocalization. ConclusionsThis study identified CDH12 as a candidate gene for kidney injury in PUV. Patient summaryWe found that variants of the CDH12 gene increase the risk of kidney injury in patients with extra flaps of tissue in the urethra (posterior urethral valves). This is the first report on this gene in this context. Our study provides interesting new information about the pathways involved and important leads for further research for this condition.

Management of Posterior Urethral Valves about 26 Cases

Aim: To improve management of the posterior urethral valve (PUV) in children in a hospital environment. Patients and Methods: This was a retrospective descriptive study that covered a sixteen (16) years period, from January 1, 2002 to December 31, 2017, In pediatric surgery and urology departments of our teaching hospital, 26 cases of posterior urethral valve (PUV) were involved. The diagnosis was made by retrograde urethrocystography and micturition, supplemented by ultrasound. Results: During this period, 26 patients (1.7%) had a PUV. The mean age of the patients was 73, 2 months with extremes ranging from 6 to 180 months. Fifteen patients consulted for dysuria, 8 for complete retention of urine. Only one patient had a history of rolling the valves to the benign ones. The main complications found were urinary tract infection in 15 children, urolithiasis in 3 children and renal failure in 2 children. Two children had serum creatinine values of 50 and 58 mg/L. The lamination of the posterior urethral valves was performed in all patients. In our series, we had one death from chronic renal failure in a 6-year-old child with a bilateral mute kidney at IVU. Conclusion: The valve diagnosis of the posterior urethra is made late because the diagnosis is still postnatal.

Urodynamics in Posterior Urethral Valve: Pursuit of prognostication or optimisation

Detrusor dysfunction is known to persist in several patients of Posterior Urethral Valve (PUV) after successful fulguration leading to progressive deterioration of renal function. Persistent bladder outlet obstruction (BOO) in the form of bladder neck hypertrophy, residual valves or strictures may contribute to progressive detrusor dysfunction. These are assessed radiologically or cystoscopically and are managed variedly by anticholinergics, alpha-adrenergic blockers or even bladder neck incision. Unfortunately, currently we do not have any objective measures to evaluate the degree of BOO in children or follow treatment outcome of any such measures. To assess the feasibility of pressure flow studies in children and proposition of an age independent index to quantify outflow parameters. We retrospectively studied the urodynamic data of the follow up cases of PUV who had been referred to us for urodynamic evaluation. Free flow uroflowmetries and filling and voiding cystometrogram were performed as per recommended protocol. Parameters like Adjusted Bladder Capacity (ABC = Voided volume+post void residue; expressed as percentage of expected bladder capacity {EBC}), overactivity, compliance, Qmax and P det at Qmax were taken into consideration. Indices like Bladder Outlet Obstruction Index (BOOI) and Bladder Contractility Index (BCI) were calculated. Multivariate analysis was run to assess correlation of ABC with other parameters. Receiver Operating Characteristics (ROC) curve analysis was performed to assess predictive values of BOOI for ABC. We did not find the ABC to change with age as has been classically described. Qmax and BCI were found to correlate with age. Values obtained for P det at Qmax and BOOI were not dependent on age and were in similar range as observed in adults. On multivariate analysis, small bladder was found to positively correlate with presence of overactivity, high BOOI and low BCI. ROC curve analysis showed a BOOI >29 could predict ABC to be <100% EBC with moderate sensitivity and specificity. Pressure flow studies are the only objective means of quantifying outlet resistance, hitherto they have been considered to be unrepresentative in children. Documentation and correction of high outflow pressures may arrest the cycle of detrusor hypertrophy and dysfunction. Quality pressure flow studies are feasible in children. Values of P det at Qmax and BOOI in children are age independent and similar to those observed in adults. BOOI can be potentially used in children to assess degree of BOO.

Cloacal dysgenesis sequence with bilateral renal agenesis, bladder agenesis, pulmonary hypoplasia and left choanal atresia: A case report

A case of posterior urethral valve is described with multiple urethroperineal fistulas. This association is extremely rare. The crucial point in the diagnosis is to distinguish these fistulas from the urethral duplications that actually guide the treatment. The presence of these fistulas in patients with posterior urethral valve may have a beneficial effect on renal function as it reduces the pressure on the bladder. On the other hand, incomplete valve ablation may contribute to the recurrence of the fistula.

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.

Multiple urethroperineal fistula in a boy with posterior urethral valve: A case report of an extremely rare association

We describe a case of posterior urethral valve with multiple urethroperineal fistulas. This association is extremely rare. The crucial point in the diagnosis is to distinguish these fistulas from the urethral duplications that actually guide the treatment. The presence of these fistulas in patients with posterior urethral valve may have a beneficial effect on renal function as it reduce the pressure on the bladder. On the other hand, incomplete valve ablation may contribute to the recurrence of the fistula.

Clinical value of early renal damage index in children hydronephrosis

Objective To explore urinary NAG, Cr, MA, α1-MG andβ2-MG as the early renal damage index in children hydronephrosis. Methods The clinical data of 206 patients in the Bayi Children′s Hospital Affiliated to the Seventh Medical Center of Chinese PLA General Hospital from May 2018 to January 2019 were analyzed retrospectively. Among them, 152 children with hydronephrosis were set as observation group, 54 children without hydronephrosis were set as control group. In the observation group, the age ranged from 1 month to 18 years old, and the median age was 2 years old. There were 123 cases of hydronephrosis caused by ureteropelvic junction obstruction (UPJO) and 29 cases of posterior urethral valve complicated with hydronephrosis. In the control group, the age ranged from 1 month to 15 years old, with a median age of 5 years. There were 18 hypospadias cases, 15 occult penis cases and 21 phimosis. All children with hydronephrosis underwent nuclear medicine renal dynamic imaging. Urine specimens were tested for urinary NAG, Cr, MA, α1-MG, and β2-MG. According to renal dynamic results, the observed components were the renal function injury group and the normal renal function group. The above indicators analyzed to judge the clinical value to find the early renal damage. Results The expression levels of urinary NAG, MA, α1-MG and β2-MG in the observation group were higher than those in the control group, and the difference was statistically significant. The expression of urinary Cr and the abnormal rate were no significant difference between any two groups(P=0.647, P=0.572). The expression levels of urinary NAG, MA, α1-MG and β2-MG were not significantly different between the normal renal hydronephrosis group and the renal function impairment group (P=0.365, P=0.448, P=0.379, P=0.338). The abnormal expression rate of Urine MA and β2-MG was not statistically significant in the patients with normal renal hydronephrosis and the renal function impairment group (P=0.436, P=0.478). MA got the highest sensitivity of (58.8%), and NAG had the highest specificity of 89.3% to detect early renal demage. Four indexes combined analysis, sensitivity, negative predictive rate, diagnostic coincidence rate improved obviously. Joint analysis of posterior urethral valves combined with hydronephrosis, the abnormal rate was 89.7%(26/29). The renal dysfunction of the posterior urethral valve showed that the renal dynamics dysfunction rate was only 37.9%(11/29). Conclusions The combined analysis of urinary NAG, MA, α1-MG and β2-MG can accurately predict early renal injury. The index of early renal loss may be the early evidence to judge whether the posterior urethral valve is complicated with upper urinary tract function injury. Key words: Hydronephrosis; Children; Early renal damage index; Clinical application

A single-center study to evaluate the efficacy of a fetal urine peptide signature predicting postnatal renal outcome in fetuses with posterior urethral valves.

Posterior urethral valves (PUVs) account for 17% of pediatric renal failure. The management of pregnancies involving fetuses with PUV is hampered by the fact that current clinical parameters obtained from fetal ultrasound and/or fetal urine biochemistry are insufficient to predict postnatal renal function. We previously have developed a fetal urine peptide signature (12PUV) that predicted with high precision postnatal renal failure at 2 years of age in fetuses with PUV. Here, we evaluated the accuracy of this signature to predict postnatal renal outcome in fetuses with PUV in an independent single-center study. Thirty-three women carrying fetuses with suspected PUV were included. Twenty-five fetuses received vesicoamniotic shunts during pregnancy. PUV was confirmed postnatally in 23 patients. Of those 23 fetuses, 2 were lost in follow-up. Four and 3 patients died in the pre- and perinatal periods, respectively. Follow-up renal function at 6 months of age was obtained for the remaining 14 patients. The primary outcome was early renal failure, defined by an eGFR < 60 mL/min/1.73 m2 before 6 months of age or pre- or perinatal death. The peptide signature predicted postnatal renal outcome in postnatally confirmed PUV fetuses with an AUC of 0.94 (95%CI 0.74-1.0) and an accuracy of 90% (95%CI 78-100). The signature predicted postnatal renal outcome for the suspected PUV cases with an AUC of 0.89 (95%CI 0.72-0.97) and an accuracy of 84% (95%CI 71-97). This single-center study confirms the predictive power of the previously identified 12PUV fetal urinary peptide signature.

MON-310 POSTERIOR URETHRAL VALVE AT A PAEDIATRIC NEPHROLOGY UNIT IN SOUTH WESTERN NIGERIA

Posterior urethral valve (PUV) is the most severe form of obstructive uropathies in the paediatric population occurring exclusively in boys. Management of posterior urethral valves is challenging in many parts of sub-Saharan Africa. To provide data on Posterior urethral valves in sub-Saharan Africa, we reviewed the cases of PUVs seen over a 21 month period. Retrospective study- information was obtained from the paediatric nephrology unit data base of children admitted with a diagnosis of posterior urethral valve between March 2016 and December 2017 Twenty-five cases were seen during the study period. Their ages ranged from 3days to 13 years with the median age been 24 months. The mean age and standard deviation was 42.1 (SD ±57.1). Eight (32%) presented during the first year of life and of this number, one (12.5%) presented in neonatal period. The commonest cause of hospital admission was urosepsis, 37.5% of the urine cultures however yielded no growth, and half of the cases were due to Pseudomonas aeroginosa. 9(32.1%) had surgical intervention (Mohan’s valve ablation or Endoscopic Valve ablation). Thirteen (%) had renal failure Three of the subjects received dialysis and of this number, two had haemodialysis. The in-hospital mortality rate is (12.0%) Posterior urethral valves are not uncommon and remain an important cause of urosepsis and chronic kidney disease in the paediatric population in sub-Saharan Africa. Efforts to further improve outcomes are needed.

Late Presentation of Posterior Urethral Valve in a 24-Year-old Man

Posterior urethral valve (PUV) is the most common cause of lower urinary tract obstruction in male neonates, with an incidence of one case per 8,000 to 25,000 live births1. The diagnosis is usually made prenatally or at birth, when male newborns are evaluated for prenatal hydronephrosis, or during early childhood, but rarely during adolescence or adulthood. Late presentation of PUV is rare and it has been estimated to account for 10% of cases2. Presentation in adulthood may occur due to the presence of a mild form of the disease devoid of the life threatening complications seen in children with the severe form3. A rare case of PUV which manifested in adulthood with lower urinary symptoms is presented to create awareness of the likelihood of the disease outside the paediatric age group.