Validation of "urinary tract dilation" classification system: Correlation between fetal hydronephrosis and postnatal...

Area of Science:

• Pediatric Urology
• Fetal Medicine
• Diagnostic Imaging

Background:

• Fetal hydronephrosis is a common finding during prenatal ultrasound.
• Predicting postnatal urological outcomes from antenatal findings remains challenging.
• A standardized classification system is needed to correlate fetal hydronephrosis with postnatal outcomes.

Purpose of the Study:

• To evaluate the correlation between fetal hydronephrosis and postnatal urological abnormalities using the urinary tract dilation (UTD) classification system.
• To assess the prognostic value of the UTD classification in isolated fetal hydronephrosis.

Main Methods:

• Prospective follow-up of 34 infants with isolated fetal hydronephrosis identified via ultrasound.
• Antenatal hydronephrosis was graded using the UTD classification system (UTD A1-3).
• Infants underwent serial postnatal ultrasounds up to 6 months, with postnatal UTD grading (UTD P1-3).

Main Results:

• Of 34 infants, 24 (70.6%) had mild antenatal hydronephrosis (UTD A1) with normal postnatal ultrasounds.
• 10 infants (29.4%) with moderate-to-severe antenatal hydronephrosis (UTD A2-3) showed persistent postnatal abnormalities (UTD P1-3).
• Vesicoureteral reflux was the most common abnormality; only 2 infants (UTD P3) required surgery for ureterovesical junction obstruction.

Conclusions:

• The UTD classification system effectively describes urinary tract changes from antenatal to postnatal periods.
• UTD grading correlates fetal hydronephrosis severity with the likelihood of persistent postnatal urological abnormalities.
• The UTD classification serves as a valuable prognostic marker for isolated fetal hydronephrosis.