Capillary Malformation-Arteriovenous Malformation Type 2, A Report of 6 Cases and Main Differential Diagnosis

Abstract

Objectives: Capillary malformation-arteriovenous malformation (CM-AVM) is a rare disorder characterized by multifocal CMs associated with AVMs. While the phenotype of CMAVM1 has been well established in the literature, there are limited published reports documenting the clinical features of CMAVM2. Our aim is to highlight this phenotype, and the distinctive features of CMAVM2 compared with CMAVM1 and hereditary hemorrhagic telangiectasia, as prompt recognition is crucial to screen for fast-flow vascular malformations, which, if left untreated, can sometimes be life-threatening. Methods: This is a retrospective review of cases seen at multiple tertiary care centers in the United States and Argentina. Results and Conclusions: We report 6 pediatric patients with CMAVM2 presenting with diffuse multifocal cutaneous CMs, telangiectases favoring the lips, perioral area and upper trunk, and Bier spots. Three patients had epistaxis. One patient had an extracranial AVM and 1 patient had Parkes Weber syndrome. EPHB4 pathogenic variants were identified in all patients. CMAVM2 remains an underrecognized condition. Genetic testing and imaging studies are recommended to guide management.