LAUSR

Key Points Question What is the prevalence and importance of congenital anomalies of the kidney and urinary tract (CAKUT) in preterm infants? Findings In this cohort study of 409 704 infants born at 23 to 33 weeks’ gestation from 2000 to 2020, 2.0% had CAKUT. CAKUT was associated with prematurity, genetic disorders, and extrarenal anomalies, and was significantly associated with risk of mortality or in-hospital morbidity, even for less severe forms such as isolated hydronephrosis. Meaning These results suggest that preterm infants with any form of CAKUT, including isolated urinary tract dilation, are at greater risk of death and severe illness, and may benefit from genetic evaluation.