Lower urinary tract obstruction: fetal intervention based on prenatal staging

Area of Science:

• Fetal Medicine
• Pediatric Urology
• Neonatal Nephrology

Background:

• Lower urinary tract obstruction (LUTO) poses significant risks to fetal renal development.
• Accurate diagnosis and prognosis are challenging, impacting management decisions.
• Prenatal intervention aims to preserve pulmonary and renal function.

Purpose of the Study:

• To present a prenatal classification system for fetal LUTO.
• To guide management decisions and fetal interventions.
• To improve outcomes for affected neonates.

Main Methods:

• Review of diagnostic criteria for fetal LUTO.
• Analysis of challenges in long-term prognosis estimation.
• Development of a disease severity classification based on ultrasound and biochemical markers.

Main Results:

• Stage I LUTO: Mild form with normal findings, requiring surveillance.
• Stage II LUTO: Moderate form with oligohydramnios, indicating vesicoamniotic shunting or cystoscopy.
• Stage III LUTO: Severe form with renal dysplasia, where shunting may not prevent renal failure.
• Stage IV LUTO: Fetal renal failure, precluding intervention.

Conclusions:

• A staged classification aids in managing fetal LUTO.
• Early intervention in Stage II LUTO can prevent pulmonary hypoplasia and renal failure.
• Late-stage LUTO (Stage IV) is associated with poor prognosis and no indication for intervention.