[Prenatal diagnosis of primary megaureter]

Area of Science:

• Pediatric Urology
• Prenatal Diagnosis
• Congenital Urinary Tract Malformations

Context:

• Prenatal diagnosis identified 22 infants with ureterovesical junction obstruction among 114 cases of urinary tract malformations.
• Exclusion criteria included infravesical obstruction or refluxing systems, ensuring focus on primary obstructive causes.
• All infants presented with normal renal function at diagnosis.

Purpose:

• To evaluate the impact and outcomes of prenatal diagnosis in infants with ureterovesical junction obstruction.
• To assess the types of malformations, treatment strategies, and complications associated with these conditions.
• To determine the diagnostic yield of prenatal diagnosis compared to postnatal detection.

Summary:

• Primary megaureter was the most common cause (n=14), followed by ureterocele (n=7) and ectopic ureter (n=1).
• Without prenatal diagnosis, only an estimated 23% of these cases would have been identified postnatally.
• Six infants had associated renal duplications, with 7 renal units showing non-function or dysplasia, particularly in ureterocele cases.
• Conservative management was applied to 14 renal units, while 11 children underwent 22 operations, including temporary diversions, for 12 units.

Impact:

• Prenatal diagnosis is crucial for identifying severe malformations, enabling timely intervention and potentially preventing long-term renal damage.
• Conservative treatment is viable for many primary obstructive megaureters, but severe renal dysplasia can be present neonatally.
• The study highlights the significant benefit of prenatal diagnosis in managing complex congenital urinary tract obstructions.