Spectrum of lymphatic anomalies in patients with RASA1-related CM-AVM

Area of Science:

• Vascular Anomalies
• Genetics
• Pediatric Medicine

Background:

• Capillary malformation-arteriovenous malformation (CM-AVM) is a vascular disorder.
• Lymphatic abnormalities are rarely reported in conjunction with CM-AVM.
• This study investigates the co-occurrence of CM-AVM and lymphatic anomalies.

Purpose of the Study:

• To describe the clinical and genetic characteristics of patients with CM-AVM and lymphatic anomalies.
• To highlight the spectrum of lymphatic abnormalities associated with CM-AVM.
• To investigate the genetic basis, specifically RASA1 mutations, in these patients.

Main Methods:

• Retrospective review of seven patients with CM-AVM and lymphatic anomalies at Boston Children's Hospital (2003-2023).
• Analysis of clinical, genetic, laboratory, and imaging findings.
• Genetic testing for RASA1 mutations in six patients.

Main Results:

• Seven patients with CM-AVM and lymphatic abnormalities were identified.
• Prenatal diagnosis in five patients included pleural effusions and ascites.
• All six genetically tested patients harbored RASA1 mutations, with three novel variants identified.

Conclusions:

• CM-AVM is associated with a range of lymphatic anomalies.
• These include effusions (pleural, pericardial), ascites, central conducting lymphatic anomaly (CCLA), and localized lymphatic malformations (LM).
• RASA1 mutations are implicated in patients presenting with CM-AVM and lymphatic anomalies.