Outcome of isolated cases of antenatal hydronephrosis and its correlation with urinary tract anomalies

Introduction: Hydronephrosis is the most common congenital disorder diagnosed by prenatal ultrasonography. Objectives: The aim of this study was to evaluate the outcome of neonates with prenatal hydronephrosis and to determine its correlation with urinary tract anomalies. Patients and Methods: This cross-sectional study was conducted on 1453 neonates with prenatal hydronephrosis. The sonography was conducted on the third day after birth. In emergency conditions, it was conducted on first day to evaluate the possible anomalies. In severely positive cases, voiding cystourethrogram (VCUG) and technetium-99m diethylenetriaminepentaacetic acid (99mTc-DTPA) scan was requested too. Accordingly in cases who hydronephrosis after birth was not existed, a sonography was repeated on the sixth week after birth. Results: The mean anteroposterior pelvic diameter (APPD) was 17.66 ± 11.2 mm. The vesicoureteral reflux (VUR) was not observed in 74.2% of 1453 case of prenatal hydronephrosis. Around, 13.8% had unilateral and 12% had bilateral reflux. In DTPA scan, 92.9% % of cases had no obstruction, while 7.1% of cases had some degree of obstruction. Ureteropelvic junction obstruction (UPJO) was seen in 72.9%, and ureterovesical junction (UVJ) obstruction was presented in 22.4% of cases. Conclusion: Antenatal diagnosis of urinary tract anomalies allowed immediate application of prophylactic antibiotics, and decreased the risk of future complications as observed in this study. Management of congenital hydronephrosis is a clinical challenge. The natural history of hydronephrosis reveals that most cases resolve spontaneously but non-operative management with close follow-up is recommended.