ESPU Meeting on Thursday 18, June 2026, 08:50 - 09:40
08:50 - 08:53
S09-1 (CP)
Silvia PECORELLI 1, Thomas BLANC 2, Matthieu PEYCELON 3, Etienne SUPLY 4, Marc-David LECLAIR 5, Sarah GARNIER 6, Pauline CLERMIDI 7, Alexis ARNAUD 8, Eric DOBREMEZ 1, Alice FAURE 9, Quentin BALLOUHEY 10, Nadia BOUDAOUD 11, Yann CHAUSSY 12, Cyril FERDYNUS 4 and Luke HARPER 13
1) CHU Pellegrin-Enfants, Bordeaux, FRANCE - 2) Necker Enfants-malade, Pediatric surgery, Paris, FRANCE - 3) Robert Debré, Pediatric surgery, Paris, FRANCE - 4) CHU de La Reunion, Saint-Denis De La Réunion, FRANCE - 5) CHU Nantes, Nantes, FRANCE - 6) CHU Montpellier, Montpellier, FRANCE - 7) Trousseau, Paris, FRANCE - 8) CHU Rennes, Rennes, FRANCE - 9) La Timone, Marseille, FRANCE - 10) CHU Limoges, Limoges, FRANCE - 11) CHU Reims, Reims, FRANCE - 12) Chu besancon, Besancon, FRANCE - 13) CHU Pellegrin-Enfants, Pediatric Surgery, Bordeaux, FRANCE
PURPOSE
Posterior urethral valves (PUV) account for approximately 17% of cases of end-stage renal failure in children. The nadir serum creatinine—currently defined as the lowest creatinine value within the first year following diagnosis—is a well-established prognostic indicator of long-term renal outcome in PUV. However, it has been criticized because determining this value requires by definition one year follow-up. This can mean delaying parental counselling and specific management pathways.
We aimed to determine the evolution of creatinine during the first year of life and determine the earliest moment when the nadir appears.
MATERIAL AND METHODS
We analyzed serum creatinine levels in a cohort of boys with PUV who underwent systematic prospective biochemical monitoring at birth, at valve resection and at 1, 3, 6, and 12 months of age following valve ablation.
RESULTS
93 patients were analyzed. Creatinine levels were elevated at valve resection (mean: 110µmol/L) but decreased exponentially during the first months of life. The minimum (nadir) value was reached by 3-4 months of age and remained stable up to one year: mean 54 µmol/l at 1 month, 43 µmol/L at 3 months, 42 µmol/L at 6 months and 44 µmol/L at 12 months
CONCLUSIONS
Nadir creatinine is thought to represent the true renal functional capacity in boys with PUV following relief of obstruction and clinical stabilization. It was traditionally defined as the lowest value within the first year, but our findings suggest that the nadir is typically achieved within 3-4 months of valve resection. We recommend redefining nadir creatinine as the lowest value reached within 3 months of valve resection, which could allow for earlier prognostic assessment and more timely parental counselling.
08:53 - 08:56
S09-2 (CP)
Silvia PECORELLI 1, Mathilde GLENISSON 2, Anne-Sophie SALLENAVE 3, Jean DELMAS 3, Aline BROCH 2, Natalie BOTTO 2, Clara WOLMER 4, Tanguy CARIOU 5, Thomas BLANC 2 and Luke HARPER 4
1) Hôpital des Enfants, CHU Bordeaux, Paediatric Surgery and Urology, Bordeaux, FRANCE - 2) Hopital NECKER-Enfants malades, Paris, Paediatric Surgery and Urology, Paris, FRANCE - 3) Hopital des Enfants, CHU de Bordeaux, Pediatric Radiology, Bordeaux, FRANCE - 4) Hopital des Enfants, CHU de Bordeaux, Paediatric Surgery and Urology, Bordeaux, FRANCE - 5) Hopital Haut-Lévêque, CHU de Bordeaux, Biostatistics, Bordeaux, FRANCE
PURPOSE
Boys with posterior urethral valves (PUV) are at risk of developing chronic kidney disease (CKD). The PURK score was developed by SickKids in Toronto to provide early risk stratification for CKD stage ≥3 and improve counselling and management.
Our aim was to evaluate the predictive performance of this score when applied to a European cohort of boys with antenatally detected PUV and to compare it to classic and "early" nadir creatinine (NC).
MATERIAL AND METHODS
We included patients born with PUV between 2012 and 2020 from two pediatric urology centers in France. We collected the neonatal variables included in the PURK score (baseline creatinine, ultrasound evidence of dysplasia, failure to thrive and high-grade vesicoureteral reflux) and the NC for each patient.
Outcomes of interest were eGFR at 1 year and 5 years. To ensure consistent scoring, all ultrasounds were reviewed by a single radiologist to confirm the presence or absence of dysplasia, the most subjective component of the score. We evaluated the predictive performance of the PURK score using the area under the receiver-operating characteristic curve (AUROC). AUROC curves were also generated for nadir creatinine (<1 year) alone and for early (< 6 months) NC. eGFR was calculated using the 2009 Bedside Schwartz Formula.
RESULTS
82 patients were included. 26% and 15% of patients had CKD stage ≥3 at 1 and 5 years respectively. The PURK model demonstrated good AUROC values for predicting CKD stage ≥3 at both 1 and 5 years [0,815 and 0,835 respectively]. Both nadir creatinine and early nadir creatinine showed better AUROC values [0,993 at 1yr and 0,998 at 5yrs] and [0,954 and 0,976 at 1-5yrs respectively].
CONCLUSIONS
The PURK score is applicable to our population, and we found it to have the same predictive capacity as the team from Toronto. However, both nadir creatinine and early nadir demonstrated a superior predictive performance of CKD stage ≥3 at both 1 and >5years of follow-up. The PURK score can give some information at presentation but creatinine within 6 months of presentation is a better predictor of long-term renal function.
08:56 - 08:59
S09-3 (CP)
Aidan WEITZNER 1, Edwin SMITH 2 and Charlotte WU 1
1) Johns Hopkins School of Medicine, Brady Urological Institute, Mobile, USA - 2) Children's Healthcare of Atlanta, Department of Pediatric Urology, Atlanta, USA
PURPOSE
Vesicoureteral reflux (VUR) has been reported to have indeterminate effects on renal outcomes in posterior urethral valve (PUV). Some studies report a deleterious effect, others no effect, and others yet a protective effect, as in VURD syndrome. We hypothesize that VUR has a deleterious effect by decreasing renal reserve, implicitly measured by creatinine nadir and velocity after establishing drainage. Herein, we take a closer look at the creatinine nadir profile of valve patients with and without reflux and re-evaluate the renal implications of reflux in valve patients.
MATERIAL AND METHODS
This is a single-center, retrospective study of patients who underwent valve ablation at age <1 year from 2002-2018. Patients were included with a minimum 2-year follow-up with Cr and voiding cystourethrogram (VCUG) data. Statistical analysis was performed to assess the association of VUR and laterality (unilateral, bilateral) with the presence of CKD3+, Cr rise from presentation (peak), and time to peak/nadir.
RESULTS
There were 79 patients with median follow up 5.8 years (IQR: 3.5, 9.5). 31 individuals developed CKD3+ and 45 had reflux present on the first VCUG (25 bilateral, 20 unilateral). Patients with reflux had significantly higher odds of developing CKD3+ compared to those without reflux (OR (95% CI): 3.4 (1.3, 9.3); p=0.020); on laterality analysis, only bilateral VUR was significantly associated with CKD3+ (OR (95% CI): 4.1 (1.5, 11); p=0.004). Patients with reflux had higher odds of having a Cr peak (OR (95% CI): 34.7 (1.8, 13); p=0.0023). In the VUR cohort, Cr peak occurred more slowly (p=0.031) compared to those with no VUR and bilateral VUR was associated with a slower time-to-nadir (p=0.0068). Average Cr was not significantly different by VUR presence at presentation (p=0.37), peak (p=0.20), or 6-week nadir (p=0.17). However, reflux was associated with a higher one-year nadir Cr (0.5; IQR 0.3, 0.9) compared to patients without reflux (0.3; IQR 0.2, 0.45; p=0.014).
CONCLUSIONS
VUR was associated with poor renal outcome and fluctuations in serum creatinine trends beyond one-year nadir, suggesting altered renal recovery dynamics and reduced reserve in this vulnerable subpopulation of children with PUV.
08:59 - 09:02
S09-4 (CP)
Aidan WEITZNER 1, Edwin SMITH 2 and Charlotte WU 1
1) Johns Hopkins School of Medicine, Brady Urological Institute, Mobile, USA - 2) Children's Healthcare of Atlanta, Department of Pediatric Urology, Atlanta, USA
PURPOSE
Serum creatinine (Cr) nadir is the strongest independent prognostic factor for long-term renal outcomes in children with posterior urethral valve (PUV). As another measure of renal reserve, early Cr trend after bladder drainage may be equally suited to predict outcomes before a nadir is declared. We newly evaluate trends in Cr velocity and Cr peak as markers for renal outcome.
MATERIAL AND METHODS
This is a single-center, retrospective study of patients who underwent successful valve ablation for PUV at age <1 year from 2002-2018. Patients were included if they had at least 2 years of follow-up with comprehensive Cr data. Statistical analyses were performed to assess the endpoint of chronic kidney disease (CKD) stage 3+. Receiver operating characteristic (ROC) curve was used to gauge the predictive capacity of Cr peak relative to Cr nadir and evaluate Cr peak cutpoints for CKD3+.
RESULTS
There were 81 patients with median follow up 5.8 years (IQR: 3.4, 9.8), and 32 developed CKD3+. Presence of a creatinine rise (Cr peak) was significantly associated with a CKD3+ outcome (88% vs 41% without CKD3+). In the CKD3+ group, Cr peak occurred more rapidly (6 days; IQR 4, 11) vs No CKD3+ (9 days, IQR 3, 24) and nadired more slowly (37 days; IQR 24, 44) vs No CKD3+ (28 days; IQR 19, 35) though differences were not significant. Average creatinine at presentation (p=0.004), peak (p<0.001), and nadir (p<0.001) were all significantly higher for the CKD3+ group with greater changes to peak and nadir. ROC analysis of Cr peak demonstrated high diagnostic accuracy for CKD3+ (AUC 95% CI): 0.82 (0.73, 0.92); p< 0.001) though did not surpass the accuracy of Cr nadir at 6 weeks or at 1 year. A Cr peak of 1.85 mg/dL was highly sensitive (81% (95% CI: 65, 91) and specific (69% (95% CI: 55, 80) for the prediction of CKD3+.
CONCLUSIONS
Patterns in Cr rise and fall differ predictably in infantile PUV patients by renal outcome. The presence and magnitude of a Cr peak are both highly predictive of CKD3+ and are early indicators of poor renal outcomes that arise before the nadir.
09:17 - 09:20
S09-5 (CP)
Kavan TAKVANI and Anil TAKVANI
Takvani Pediatric Urology Hospital, Urology, Ahmedabad, INDIA
PURPOSE
Neonatal MCU/VCUG is traditionally performed with an intravesical feeding tube (IFT). Crossing the entire urethra and distending the bladder perforates posterior urethral valve leaflets and alter native urethral morphology, potentially blunting urethral diagnostic signs and complicating endoscopic identification/fulguration. A low-pressure meatal-cannula MUCG avoids intravesical instrumentation and aims to preserve anatomy while providing physiologic voiding images. IFT placement, often despite topical anaesthesia requires trans-sphincteric urethral catheterization that is painful, distressing, and risks mucosal trauma. By contrast, the meatal-cannula MUCG minimizes instrumentation (no intravesical device, no injection), uses only a distal cannula with topical lignocaine and swaddling, avoids crossing the sphincter, reduces manipulation time, and is generally better tolerated.
MATERIAL AND METHODS
Single-centre retrospective comparison (n=60 neonates, 2019-2025): Routine IFT-MCU (n=30) vs Modified MUCG (n=30). Modified technique: 22-24G cannula placed only into the anterior urethra, slow instillation of 8-12 mL warm diluted non-ionic contrast, voiding cine.
Primary (urethra-centric) outcomes: (i) diagnostic confidence (Likert ≥ 4), (ii) Urethral Visualization Index (UVI, 0-3) summing: dilated posterior urethra (PU), hypertrophied/bladder-neck impression (BN), smooth posterior-anterior cutoff.
Cystoscopy: visualization quality (Good/Moderate/Poor) and need for redo. Safety: complications ≤7 days. χ²/Fisher where appropriate; α=0.05.
RESULTS
Sixty neonates were included (modified MUCG n=30; routine IFT-MCU n=30). Diagnostic adequacy (Likert ≥ 4) was 26/30 (86.7%) with the modified technique vs 23/30 (76.7%) with routine MCU (risk difference +10.0 pp; non-inferior vs a −15% margin; one-sided 97.5% CI above −15%; p≈0.32 for superiority). Urethral visualization favored the modified approach: UVI median 2.8 vs 2.5; key components—dilated posterior urethra 27/30 (90.0%) vs 26/30 (86.7%), bladder-neck impression 20/30 (66.7%) vs 18/30 (60.0%), and smooth posterior-anterior cutoff 26/30 (86.7%) vs 20/30 (66.7%) (Δ +20.0 pp; p≈0.07). Cystoscopy showed higher "acceptable" visualization (Good+Moderate) with the modified technique 29/30 (96.7%) vs 22/30 (73.3%) (Δ +23.4 pp; p≈0.01), with fewer redos 1/30 (3.3%) vs 4/30 (13.3%) (p≈0.16). Complications ≤7 days were comparable 1/30 (3.3%) vs 2/30 (6.7%) (p≈0.55).
CONCLUSIONS
The meatal-cannula MUCG is non-inferior for diagnostic adequacy while delivering clear urethral-visualization advantages—notably a higher rate of the smooth posterior-anterior cutoff—and significantly better intra-operative valve visualization, with no increase in early complications and fewer redos. Beyond measured outcomes, the technique avoids IFT insertion in fragile neonates, removing a step that can alter valve morphology—a practical win for both imaging and surgery. Prospective validation is warranted.
09:20 - 09:23
S09-6 (CP)
Alina PUZKO and Maksym PONOMARENKO
National Specialized Children's Hospital "Okhmatdyt", Department of Pediatric Urology, Kyiv, UKRAINE
PURPOSE
Posterior urethral valve (PUV) is a major cause of infravesical obstruction in male infants. Despite the increasing use of laser technology, the choice of the optimal method of valve incision remains controversial.
The aim of this study was to compare the effectiveness of cold-knife incision and laser ablation in newborns and young infants.
MATERIAL AND METHODS
A total of 61 boys aged 3 days to 4 months were included between 2022 and 2025:
• Group I (n = 32): cold-knife incision
• Group II (n = 29): laser incision
Due to age limitations, uroflowmetry was not performed. Evaluation included voiding characteristics, ultrasound findings (hydronephrosis, ureteral dilation, residual urine), and the need for reintervention. All patients received postoperative prophylactic antibacterial therapy.
The mean follow-up period was 6 months, until complete regression of upper urinary tract dilation on ultrasound.
RESULTS
• Complete relief of obstruction was achieved in 90.6% (29/32) after cold-knife incision and 65.5% (19/29) after laser ablation (p < 0.05).
• Reintervention for persistent symptoms or ultrasound signs of obstruction was required in 34.5% (10/29) after laser treatment.
• In 5 infants (17.2%), repeat cold-knife incision after initial laser ablation resulted in full restoration of urinary flow.
• In the cold-knife group, only 3 patients (9.4%) required reintervention.
• No intraoperative or postoperative complications were observed. Mild transient hematuria during the first 7 days did not require treatment.
CONCLUSIONS
Cold-knife incision of posterior urethral valves in newborns and infants is more effective than laser ablation. Laser-treated patients demonstrated a higher rate of persistent obstruction and need for repeat procedures, while the cold-knife technique provided more complete valve removal without increasing complication risk
09:23 - 09:26
S09-7 (CP)
Aurora LÖVEGREN 1, Tor-Björn CLAESSON 2, Seppo TASKINEN 1 and Niklas PAKKASJÄRVI 1
1) New Children's Hospital, Helsinki University Hospital, Department of Pediatric Surgery, Section of Urology, Helsinki, FINLAND - 2) New Children's Hospital, Helsinki University Hospital, Department of Pediatric Radiology, Helsinki, FINLAND
PURPOSE
Many infants with posterior urethral valves (PUV) are initially dependent on catheter drainage. Only two studies have evaluated how a urinary catheter affects PUV diagnostics during voiding cystourethrography (VCUG), however, these are limited by heterogeneous age groups, small number of PUV-patients, and a lack of systematic blinding. We aimed to determine whether the presence of a urethral catheter alters the detection of PUV on VCUG in a neonatal, age-matched single-center cohort using blinded image assessment.
MATERIAL AND METHODS
After institutional approval, we identified all PUV-patients treated at our institution between 2000-2024, who underwent VCUG within the first month of life (N= 44). These were compared with an age- and size-matched reference group undergoing VCUG at a similar age. All imaging assessment was randomized and blinded to clinical data. The primary outcome was the identification of PUV on VCUG performed with a urethral catheter in place. Secondary outcomes included the proportion of VCUG examinations rated diagnostically sufficient and reasons for insufficient image quality.
RESULTS
Fifty-two examinations (59%) were rated diagnostically sufficient for PUV evaluation (VCUG imaging available both with and without a catheter), forming the analytic cohort (19 PUV; 33 controls). 17/19 PUV patients were correctly identified with two false negatives. There was an absolute consensus between the imaging with and without a catheter. No false positives occurred in the control group. VCUG with a catheter presents thus with the sensitivity of 89,5% (95% CI 68.6-97.1) and specificity of 100% (95% CI 89.6-100) for identifying PUV. 36 examinations were discarded due to lack of imaging both with and without a catheter (N=20), with suprapubic catheter (N=7) and poor quality of imaging (N=9). When combined with the two previous studies addressing this question, catheter-in VCUG demonstrated a pooled sensitivity of 90% (45/50; 95% CI 78.7-95.6) for detecting PUV.
CONCLUSIONS
In this cohort, the presence of a urethral catheter did not reduce the diagnostic performance of VCUG for PUV. Image-quality limitations were unrelated to catheter presence, and among diagnostically sufficient studies, VCUG with an indwelling catheter remained accurate. These findings suggest that routine catheter removal during the voiding phase is not required and may simplify the examination without compromising diagnostic accuracy.