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Evaluation of congenital anomalies of the kidney and urinary tract (CAKUT)

Norman D Rosenblum, MD, FRCP
Section Editors
Tej K Mattoo, MD, DCH, FRCP
Laurence S Baskin, MD, FAAP
Deputy Editor
Melanie S Kim, MD


Congenital anomalies of the kidney and urinary tract (CAKUT) constitute approximately 20 to 30 percent of all anomalies identified in the prenatal period [1]. Routine antenatal ultrasonography during pregnancy detects the majority of CAKUT.

Antenatal screening for CAKUT and the postnatal evaluation of infants diagnosed prenatally with CAKUT are discussed here.


The majority of renal malformations are detected antenatally because of the widespread use and sensitivity of fetal ultrasonography. In 2002, a prenatal ultrasound was performed in about two-thirds of all live births in the United States. The frequency of congenital anomalies of the kidney and urinary tract (CAKUT) as detected sonographically in unselected populations has been reported to be between 0.1 to 0.7 percent [2-4].

In general, the optimal timing recommended for a screening antenatal ultrasound is between 16 to 20 weeks of gestation because of the following factors at this gestational age:

There is good visualization of anatomy with a high sensitivity in detecting anomalies.

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Literature review current through: Nov 2017. | This topic last updated: Mar 30, 2016.
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