Pigment-vascular phacomatoses Q85.8

Group of very rare (about 250 cases have been described) binary genodermatoses with coexisting extensive vascular malformations and a (large-area) melanocytic nevus, in which the common occurrence is not a coincidence but is evaluated as an entity. Sometimes internal organs are involved, especially the central nervous system and the eyes.

• Type I: Nevus flammeus combined with nevus pigmentosus verrucosus
• Type II: Naevus flammeus combined with Mongolian spot (dermal melanocytosis)
• Type III: Naevus flammeus (naevus roseus) combined with naevus spilus (phacomatosis spilorosea)
• Type IV: Naevus flammeus combined with naevus spilus and Mongolian spot, possibly also naevus anaemicus

Types II, III and IV may be associated with a naevus anaemicus. The individual types are further classified according to a) and b), depending on whether a) exclusively cutaneous or b) additional systemic involvement, e.g. dysplasia of larger vessels (e.g. vena cava), is present.

Genodermatosis with sporadic occurrence. It was assumed that this phacomatosis is caused by a nonallelic didymosis ( twin spotting). However, it has been shown that in another form of twin spotting(phacomatosis pigmentokeratotica) a somatic HRAS mutation (chromosome 9q21.2) in an early progenitor cell leads to differentiation of different tissue types.

Not recommended

1. Convalexius P et al. (2017) Congenital telangiectatic and pigmented lesions associated with lymphedema
   ,difference in leg length, and scoliosis.J Dtsch Dermatol Ges 15:751-753.
2. Fischer K (2015) Phacomatosis pigmentovascularis. JDDG 13: 1178-1179
3. Happle R, Steijlen PM (1989) Phacomatosis pigmentovascularis interpreted as a phenomenon of twin spots. dermatologist 40: 721-724
4. Lo PY, Tzung TY (2003) Phacomatosis pigmentovascularis type IIb with a patent umbilical vein and inferior vena cava hypoplasia. Br J Dermatol 148: 836-838
5. Nimizu N et al (2015) Unusual case of phakomatosis pigmentovascularisin a Japanese female infant associated with three phakomatoses: Port-wine stain, dermal melanocytosis and cutis marmorata telangiectatica congenita. J Dermatol 42:1006-1007
6. Ota M, Kawamura T, Ito N (1947) Phacomatosis pigmentovascularis (Ota). Jpn J Dermatol 52: 1-3
7. Yang Yet al (2015) Phacomatosis Pigmentovascularis associated with Sturge-Weber Syndrome, Ota Nevus, and congenital glaucoma. Medicine (Baltimore) 94:e1025