Fetal bladder outflow obstruction: Interventions, outcomes and management uncertainties

Area of Science:

• Fetal medicine
• Pediatric urology
• Medical imaging

Background:

• Fetal lower urinary tract obstruction (LUTO) presents with characteristic prenatal ultrasound findings like a dilated bladder and keyhole sign.
• LUTO encompasses various conditions including posterior urethral valves, urethral atresia/stenosis, Prune-Belly Syndrome, and cloacal anomalies.
• These conditions are part of the Congenital Anomalies of Kidney and Urinary Tract (CAKUT) spectrum, a leading cause of pediatric end-stage renal disease.

Purpose of the Study:

• To review the diagnostic criteria and differential diagnoses of fetal LUTO.
• To discuss recent advancements in predicting postnatal renal function from prenatal findings and fetal biochemistry.
• To outline current in-utero and postnatal management strategies and highlight future research directions.

Main Methods:

• Review of prenatal ultrasound findings for LUTO diagnosis.
• Analysis of fetal biochemistry and established staging systems for outcome prediction.
• Description of current in-utero therapeutic interventions and postnatal management.

Main Results:

• Prenatal ultrasound is key for LUTO diagnosis, though differential diagnoses exist.
• Predictive features and staging systems are emerging to guide counseling and intervention selection.
• In-utero therapies like shunting and cystoscopy are available, with ongoing efforts to improve outcomes.

Conclusions:

• Accurate prenatal diagnosis and risk stratification are crucial for managing fetal LUTO.
• In-utero interventions offer potential benefits, but careful patient selection is necessary.
• Further research is needed to optimize management and improve long-term renal function in CAKUT patients.