Anterior urethral valve associated with posterior urethral valves

Isolated Posterior Urethral Valves and Anterior Urethral Valves With and Without Concomitant PUV: Matched Cohort Study at a High-risk Pediatric Center

OBJECTIVE

To compare postnatal outcomes of anterior urethral valves (AUV) and posterior urethral valves (PUV) patients to evaluate for potential differences between these conditions, given that AUV with or without concomitant PUV is a rare congenital anomaly leading to lower urinary tract obstruction (LUTO).

METHODS

We reviewed our LUTO database and included patients with AUV or concomitant AUV+PUV, managed at our institution between 2003 and 2023 matching them to comparable PUV cases. Assessed variables included prenatal diagnosis, gestational age (GA) at birth, initial management, kidney function, presence and degree of hydronephrosis (HN), and need for renal replacement therapy (RRT).

RESULTS

The AUV ± PUV group (AUV: n = 11, concomitant PUV: n = 2) and PUV group (n = 26) had similar presenting ages and follow-up times (P >.05). Only 15.4% of AUV cases presented prenatally compared to 72.0% of PUV cases (P = .0016), leading to delayed postnatal management in AUV patients (P = .0260). Findings at presentation included UTI, weak stream or a palpable penile mass. PUV patients demonstrated significantly higher creatinine levels at the initial visit and at last follow-up (P = .0120 and P = .0302) than the AUV ± PUV group, with only 1 patient requiring RRT (P >.05). At the last follow-up, no patient in the AUV ± PUV group required clean intermittent catheterization compared to 37.5% in the PUV group (P = .0331) which also demonstrated more patients with persistent HN (P = .0039).

CONCLUSION

AUV with or without concomitant PUV is a rare finding that should be considered in patients presenting with weak stream, UTI, and penile swelling. Our data suggest potential differences in presentation and less severe postnatal outcomes in AUV compared to PUV patients.

PUVs are more common in boys with hypospadias

INTRODUCTION

The association between posterior urethral valves (PUVs) and hypospadias has previously been reported in case reports. After the identification of this twin pathology in a number of patients, a national retrospective review of all patients with this dual diagnosis was performed.

PATIENTS AND METHODS

All patients were identified in each centre from surgical databases of prospectively collated information on all surgical procedures. The medical notes were reviewed to ascertain demographics, the type of hypospadias, the mode of presentation of the valves and the outcome.

RESULTS

Twenty-eight patients who had the dual diagnosis of hypospadias and PUV between 2002 and 2017 in the four tertiary paediatric centres where specialist paediatric urology is undertaken in our country were identified. Most patients (n = 24) had the valves diagnosed after hypospadias surgery. The median age at the time of hypospadias surgery was 1.4 years (range 1-4 years). There were 12 proximal and 16 mid or distal hypospadias. The commonest presentation was with problems voiding after surgery in 14 cases with a further seven boys who had urinary tract infections. Four patients had a urethro-cutaneous fistula after repair that initiated further assessment. Two boys had distal dehiscence of their repair. There was one boy presented with new onset daytime incontinence. The median time of follow-up after valve incision surgery was 4.9 years (range 0.1-12.3 years). Twenty-two patients (three pre toilet training) had no ongoing urinary symptoms. Twenty-one boys have normal renal function with one patient in stage 3b chronic kidney disease. The incidence of this dual diagnosis in Scotland is estimated at one in 100 cases of hypospadias in the paediatric population.

CONCLUSION

The incidence of PUV in boys with hypospadias is estimated at 1% patients.

Lower urinary tract development and disease

Congenital anomalies of the lower urinary tract (CALUT) are a family of birth defects of the ureter, the bladder, and the urethra. CALUT includes ureteral anomaliesc such as congenital abnormalities of the ureteropelvic junction (UPJ) and ureterovesical junction (UVJ), and birth defects of the bladder and the urethra such as bladder-exstrophy-epispadias complex (BEEC), prune belly syndrome (PBS), and posterior urethral valves (PUVs). CALUT is one of the most common birth defects and is often associated with antenatal hydronephrosis, vesicoureteral reflux (VUR), urinary tract obstruction, urinary tract infections (UTI), chronic kidney disease, and renal failure in children. Here, we discuss the current genetic and molecular knowledge about lower urinary tract development and genetic basis of CALUT in both human and mouse models. We provide an overview of the developmental processes leading to the formation of the ureter, the bladder, and the urethra, and different genes and signaling pathways controlling these developmental processes. Human genetic disorders that affect the ureter, the bladder and the urethra and associated gene mutations are also presented. As we are entering the postgenomic era of personalized medicine, information in this article may provide useful interpretation for the genetic and genomic test results collected from patients with lower urinary tract birth defects. With evidence-based interpretations, clinicians may provide more effective personalized therapies to patients and genetic counseling for their families.

Urodynamic changes in patients with anterior urethral valves: before and after endoscopic valve ablation

PURPOSE

To retrospectively review a series of children with anterior urethral valves (AUV), with emphasis on patterns of urodynamic change and long-term outcome of endoscopic treatment.

PATIENTS AND METHODS

We reviewed the medical records of eight patients who had undergone thorough radiological and urodynamic exams before and after treatment. The diagnosis of AUV was based on radiological imaging and confirmed by urethrocystoscopy. The valves were ablated through either transurethral fulguration or resection. The upper urinary tracts were studied by renal scan and ultrasonography before and after the procedure. Bladder function was assessed urodynamically 3 months after surgery. Uroflowmetry was performed as soon as the children were toilet trained.

RESULTS

Endoscopic ablation of AUV was successful in all cases and no surgical complications occurred. The initial symptoms resolved in all boys. VUR disappeared in two out of three patients, and five children had bladder trabeculation that was resolved after surgery. The final outcome was successful in seven patients (88%). The major urodynamic dysfunction was bladder hypercontractility that resolved following valve ablation. The mean maximum voiding detrusor pressure (P(detmax)) decreased from 213.2+/-17.9 cmH(2)O to 80.7+/-9.9 cmH(2)O, 6 months after treatment (P<0.001). None of the patients had low-compliant bladder, detrusor instability or myogenic failure. The voiding pattern in all toilet-trained patients was staccato and of an interrupted shape prior to surgery, but changed to a normal bell-shaped voiding pattern following valve ablation.

CONCLUSION

AUV should be considered in the differential diagnosis of patients presenting with infravesical obstruction. We recommend endoscopic valve ablation as the treatment of choice.