Antenatal and postnatal management of posterior urethral valves: where do we stand?

Abstract

Introduction Posterior urethral valve (PUV) is the leading etiology of lower urinary tract obstruction (LUTO) in boys and is an important cause of end-stage renal disease (ESRD) in children. The aim of this article is to review the current status on antenatal intervention for PUV as well as postnatal medical and surgical management. Main body MEDLINE, EMBASE, Pubmed and Google Scholar search was conducted throughout December 2020 using the keywords: posterior urethral valves, congenital urinary obstruction, antenatal, valve bladder syndrome, medical, anticholinergics, alpha blocker, antibiotics, biofeedback, diversion, augmentation cystoplasty and renal transplantation. Only papers written in English were included. The relevant literature was summarized. Despite advances in antenatal intervention for fetal LUTO, it remains associated with considerable fetal and maternal morbidity. Patient selection criteria for antenatal intervention are greatly debated. Fetal intervention has resulted in improved perinatal survival in properly selected cases, with a questionable benefit to postnatal renal function. There is decent evidence supporting the use of anticholinergics in infants and young children following valve ablation, with less robust evidence advocating alpha blockers, overnight catheter drainage and biofeedback. The role of urinary diversion remains contentious. Optimizing bladder dynamics is crucial for successful renal transplantation outcomes. Conclusion While antenatal intervention has failed to improve renal function outcomes of PUV, patient-centered medical and sometimes surgical interventions can help delay the progression of chronic kidney disease. Lifelong monitoring and management of the associated bladder dysfunction is indispensable even after successful renal transplantation.

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

“…In contrast to the studies by Brownlee et al . [ 26 ] and Abdelhalim and Hafez[ 27 ] where the incidence of antenatal detection of PUV was 37%–53%, the incidence in our study was 20% only. This highlighted the need for an improved antenatal screening program at our institute.…”

Can concomitant bladder neck incision and primary valve ablation reduce early re-admission rate and secondary intervention?

“…The diagnosis of secondary bladder neck obstruction is, however, more challenging, often requiring videourodynamic assessment (4). Management of PUV sequelae is dictated by the pattern of bladder dysfunction (15)(16)(17). A variety of therapeutic options have been suggested to treat secondary BN obstruction in PUV patients including alpha-blockers, botulinum toxin injection into the BN or BNI (4,8,9).…”

Ultrasound and magnetic resonance imaging features of fetal urogenital anomalies: A pictorial essay

“…Other causes of LUTO include urethral stricture, urethral agenesis, persistent cloaca, megacystis-microcolonintestinal hypoperistalsis syndrome, and prune-belly syndrome. 57…”

“…MRI allows better assessment of the posterior urethra and assists in distinguishing the etiology of fetal hydronephrosis other than PUV (Figure 6). Other causes of LUTO include urethral stricture, urethral agenesis, persistent cloaca, megacystis‐microcolonintestinal hypoperistalsis syndrome, and prune‐belly syndrome 57 …”