Capillary malformations: a classification using specific names for specific skin disorders

The name capillary malformation has caused much confusion because it is presently used to designate numerous quite different disorders such as naevus flammeus, the salmon patch, the vascular naevus of the hereditary 'megalencephaly-capillary malformation syndrome' and the skin lesions of non-hereditary traits such as 'capillary malformation-arteriovenous malformation' and 'microcephaly-capillary malformation'. To avoid such bewilderment, the present review describes the distinguishing clinical and genetic criteria of 20 different capillary malformations, and a specific name is given to all of them. The group of capillary naevi includes naevus flammeus, port-wine naevus of the Proteus type, port-wine naevus of the CLOVES type, naevus roseus, rhodoid naevus, cutis marmorata telangiectatica congenita, congenital livedo reticularis, segmental angioma serpiginosum, naevus anaemicus, naevus vascularis mixtus and angiokeratoma circumscriptum. Capillary lesions that perhaps represent naevi are the mesotropic port-wine patch, Carter-Mirzaa macules, unilateral punctate telangiectasia and unilateral naevoid telangiectasia of the patchy type. Capillary malformations that do not represent naevi include X-linked angiokeratoma corporis diffusum (Fabry disease), autosomal dominant angiokeratoma corporis diffusum, hereditary haemorrhagic telangiectasia, hereditary angioma serpiginosusm and the salmon patch. In this way, we are able to discriminate between various non-hereditary capillary naevi such as naevus roseus and the hereditary rhodoid naevus and several hereditary traits that do not represent naevi such as angiokeratoma corporis diffusum and hereditary haemorrhagic telangiectasia; between four different types of port-wine stains, three of them being lateralized and one being mesotropic; between cutis marmorata telangiectatica congenita and congenital livedo reticularis; between telangiectatic naevi and the vasoconstrictive naevus anaemicus; and between two different types of angiokeratoma corporis diffusum. Finally, arguments are presented why the salmon patch ('stork bite', 'naevus simplex') cannot be categorized as a naevus.