[The prenatal development of nephrological abnormalities detected during pregnancy]

The objective of the present study was to evaluate the conformity between the pathological prenatal ultrasound findings of the kidney and urinary tract during fetal life and in the neonatal period.

In a period of four years (1991-1994) 14,938 pregnant woman were controlled in our hospital by performing at least one prenatal ultrasound during the third trimester of their pregnancy to detect alterations of the kidneys and fetal urinary tract. In those newborns with a positive fetal ultrasound, a renal ultrasonography study was performed in the first week of life.

Anomalous fetal images at the level of the kidney and/or urinary tract were found in 71 cases (0.5% of all fetuses studied), with sonography during the neonatal period confirming 46.5% of them. The most common fetal images found were pyelocaliceal dilatation in 58 cases (82% of the total) and amongst these mild cases (with renal pelvis diameter less than 10 mm) with 39 cases (55%) none of which malformation of the urinary tract could be diagnosed. In the extreme opposite, the images of severe pyelocaliceal dilatation (pelvic diameter greater than 15 mm), renal cystic images and images of agenesis or renal hypoplasia were interrelated very well (100%, 75% and 100%, respectively) with the neonatal ultrasound findings.

We want to indicate the great help that fetal ultrasound provides in the precocious diagnosis of nephrourological malformations in the newborn.