Prenatal Clinical Findings in RASA1-Related Capillary Malformation-Arteriovenous Malformation Syndrome

Pathogenic variants in RASA1 are typically associated with a clinical condition called capillary malformation-arteriovenous malformation (CM-AVM) syndrome, an autosomal dominant genetic disease characterized by a broad phenotypic variability, even within families. In CM-AVM syndrome, multifocal capillary and arteriovenous malformations are mainly localized in the central nervous system, spine and skin. Although CM-AVM syndrome has been widely described in the literature, only 21 cases with prenatal onset of clinical features have been reported thus far. Here, we report four pediatric cases of molecularly confirmed CM-AVM syndrome which manifested during the prenatal period. Polyhydramnios, non-immune hydrops fetalis and chylothorax are only a few possible aspects of this condition, but a correct interpretation of these prenatal signs is essential due to the possible fatal consequences of unrecognized encephalic and thoracoabdominal deep vascular malformations in newborns and in family members carrying the same RASA1 variant.

Automated summary

Pathogenic variants in RASA1 are associated with CM-AVM syndrome, which is characterized by a wide phenotypic variability, mainly affecting the central nervous system, spine, and skin. This condition has rarely been reported during the prenatal period, but it is important to recognize its prenatal signs due to the potential fatal consequences of undetected vascular malformations in newborns and family members.