Abstract:

Objective: To investigate the incidence of congenital anomalies of the kidney and urinary tract (CAKUT) in neonates, and to evaluate the value of urinary ultrasound screening in the early postnatal period.Methods: The neonates born or treated in Beijing Tsinghua Changgung Hospital affiliated to Tsinghua University between January 2016 and December 2018 accepted the urinary ultrasound scree-ning, and the neonates with problem were followed up. In the meanwhile, the maternal pregnancy data were analyzed to screen out the risk factors associated with the onset of CAKUT.Results: (1)A total of 2 655 neonates were screened by ultrasonography,of whom 82 neonates had been diagnosed with CAKUT(male: 60 cases,female: 22 cases),the positive rate was 3.1%(82/2 655).There were 66 cases of hydronephrosis, 6 cases of duplicate kidney, 2 cases of multiple renal cysts, 2 cases of renal cystic dysplasia, 1 case of medullary sponge kidney, 3 cases of small kidney, 1 case of isolated kidney, and 1 case of horseshoe kidney.(2)Of the 66 children with hydronephrosis, 4 cases were lost to the follow-up; 8 cases were followed for less than six months with no significant changes found, and still in the follow-up observation; 54 cases were followed up for 1 year, among which 32 cases were returned to normal within 1 year, 3 cases were alleviated, 7 cases were aggravated, and 12 cases were unchanged. One case underwent surgery for repeated urinary tract infections and decreased renal function.(3) Abnormal fetal urinary ultrasound in the late pregnancy was found to be the most common in the high risk factors of CAKUT. There were 44 high-risk newborns with abnormal fetal urinary ultrasound,and 35 cases of CAKUT were diagnosed after birth. The incidence rate was 79.5%(35/44). (4)Among the 2 655 newborns screened, 2 611 newborns had normal antenatal urinary ultrasonography. Among these neonates with normal urinary ultrasound during pregnancy,47 cases of CAKUT were diagnosed after birth, with an incidence of 1.8%(47/2 611).Conclusion: The most common CAKUT in neonates is hydronephrosis and most cases with hydronephrosis had a good prognosis, but they should be followed up regularly. Urinary ultrasound screening for neonates, especially those high-risk neonates with abnormal fetal urinary ultrasound, has important clinical implications for the early detection of CAKUT.

Key words: Anomalies, kidney and urinary tract, congenital, Ultrasonography, Neonates