Prenatal overgrowth and polydramnios: Would you think about Noonan syndrome?

ABSTRACT

We report on a child with prenatal findings of increased nuchal translucency, polydramnios, ascites, and overgrowth. At birth, she presented length >97° centile, minor facial anomalies, megalencephaly, and Wolff-Parkinson-White syndrome. Whole-exome sequencing showed a pathogenic variant in the NRAS gene, but no mutations were found in PI3K/AKT/mTOR pathway genes.