Document Type : Original Article

Authors

1 Department of Pediatrics, Clinical Research Development Unit of Rouhani Hospital, Amirkola Children's Non-Communicable Diseases Research Center, Babol University of Medical Sciences, Babol, Iran

2 Student Research Committee, Babol University of Medical Sciences, Babol, Iran

3 Department of Midwifery and Reproductive Health, Social Determinants of Health Research Center, Health Research Institute, Babol, Iran

4 Department of Pediatrics, Amirkla Children's Non-Communicable Disease Research Center, Babol University of Medical Sciences, Babol, Iran

5 Department of Biostatistics & Epidemiology, Social Determinants of Health Research Center, Health Research Institute, Babol, Iran

6 Department of Gynecology and Obstetrics, Clinical Research Development Unit of Rouhani Hospital, Babol University of Medical Sciences, Babol, Iran

7 Research Development Unit of Ayatollah Rouhani Hospit Clinical Research Development Unit of Rouhani Hospital al, School of Medicine, Babol University of Medical Sciences, Babol, Iran

8 Department of Radiology, Clinical Research Development Unit of Rouhani Hospital, School of Medicine, Babol University of Medical Sciences, Babol, Iran

10.22038/ijn.2024.74690.2445

Abstract

Background: Prenatal hydronephrosis (PNH) may be associated with congenital abnormalities in the urinary tract. This study aimed to determine and follow up on the fetus diagnosed with PNH until the first six months after birth.
Methods: This prospective longitudinal study was conducted from May 2021 to July 2022 in fetuses who were diagnosed with PNH based on the size of the anterior-posterior diameter of the renal pelvis (APRPD) by a perinatologist with an S W 80 ultrasound machine. If it is ≥ 4 mm in the 2nd and ≥ 7 mm in the 3rd trimesters, it is considered PNH. These infants were followed up until the first six months after birth. Data analysis was performed using SPSS 20, Chi-square, Fisher's exact, and T-tests.
Results: Of the 56 eligible fetuses, 50 fetuses were followed up. The mean gestational age at the time of diagnosis of PNH was 20.48 ± 5.37 weeks. Twenty cases of PNH (45.45%) spontaneously improved until birth. Thirty cases had hydronephrosis in the first week after birth, 16 of which (53.33%) were bilateral. The cause of PNH in 90% is idiopathic. Other causes include polycystic kidney, vesicoureteral reflux, and posterior urethral valve. One case died in the first week after birth. Forty-three cases had spontaneous recovery of PNH by six months, and 6 cases (12%) had adverse outcomes. The severity of PNH in the 3rd trimester had a significant relationship with adverse outcomes (P=0.001). The APRPD in the 3rd trimester has more sensitivity and specificity than in the 2nd trimester for predicting adverse outcomes after birth.
Conclusion: In most cases, the cause of PNH is idiopathic, and the resolution of PNH occurs up to 6 months after birth. Moderate and severe PNH was associated with a poorer outcome and requires more follow-up and intervention.
 

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