The Diagnostic Efficacy of and Requirement for Postnatal Ultrasonography Screening for Congenital Anomalies of the Kidney and Urinary Tract

Background: We aimed to investigate the effectiveness of postnatal ultrasonography in determining congenital anomalies of the kidney and urinary tract in term infants with or without a history of congenital anomalies of the kidney and urinary tract in the prenatal period. Methods: In this retrospective cohort study, the records of term infants aged between six weeks and three months undergoing urinary system ultrasonography during routine child care were examined. Results: Congenital anomalies of the kidney and urinary tract was determined in 121 (4.62%) of the 2620 cases included in the study. The most common anomaly was hydronephrosis (in 69.4% of the congenital anomalies of the kidney and urinary tract cases and 3.21% of all cases). Thirty-two of the 84 (38.1%) hydronephrosis cases detected by postnatal ultrasonography, three of the nine (33.3%) renal agenesis cases, four of the seven (57.1%) horseshoe kidneys cases, one of the four (25%) multicystic dysplastic kidney cases and two of the two (100%) duplex system cases could not be detected by prenatal ultrasonography. On the other hand, hydronephrosis was not detected at postnatal ultrasonography in 29 (1.1%) cases which detected mild or moderate hydronephrosis by prenatal ultrasonography scanning. Conclusions: In our study, it was observed that approximately one-third of the cases of hydronephrosis, unilateral renal agenesis, duplex system, horseshoe kidney, and ectopic kidney could not be detected at prenatal ultrasonography screening. We therefore believe that, in addition to prenatal ultrasonography screening, postnatal ultrasonography screening of all children for urinary tract anomalies would be beneficial.