What is nevus flammeus?
Nevus flammeus (also known as Port wine stain) is a vascular birthmark.Port wine stain is a lateral telangiectatic nevus. Unlike salmon patch, this flammeus birthmark is a rare finding in newborns and usually persists throughout the life of the individual. Though these birthmarks can appear anywhere on the body, they occur more often on the face and then on neck and upper trunk. Initially, the port wine stain appears as flat and pink lesion. As the child grows, the birthmarks deepen in color to dark red or purple. In adults the nevus flammeus birthmarks thicken and become uneven and lumpy.
A few cases of acquired port wine stains appearing in adults had been reported. Port-wine stain birthmarks may be part of a syndrome such as Sturge–Weber syndrome or Klippel–Trénaunay–Weber syndrome. In some cases these birthmarks have been attributed to c.548G→A mutation in the GNAQ gene. Some researchers described an association with RAS p21 protein activator 1 (RASA1), a 120-kDa cytosolic human protein. The increase in the presence of vascular endothelial growth factor (VEGF)–A and its most active receptor VEGF-R2 may be contributing to the vessel proliferation and/or vasodilatation.
Nevus flammeus causes
The nevus flammeus birthmark is caused by defective vasculature of the skin. Primarily, the vasculature of the superficial plexus in the dermal skin shows enlargement or dilation of capillaries. The cutaneous sympathetic innervation in the perivascular region brings about vasoactive responses to both vasodilating and vasoconstricting stimuli. Inadequate innervation in nevus flammeus birthmark area may be responsible for decreased vascular tone and progressive vascular dilatation.In case of salmon patch (nevus simplex), there appears to be a defect/delay in maturation of cutaneous sympathetic innervation, which clears up as the infant grows. However, in the case of nevus flammeus birthmark, there is loss of associated peripheral nervous elements in the affected perivascular region. Such condition leads to reduced vasoactive responses to vasodilating and vasoconstricting stimuli and permanent dilation of capillaries. There may be fluid accumulation and cellular infiltration in the perivascular region of port wine stain birthmarks leading to uneven skin.
Nevus flammeus diagnosis
Port wine stain birthmarks are usually diagnosed based entirely upon the history and appearance. In some cases skin biopsy may be performed to confirm the diagnosis. The birthmarks near eye or on the eyelid may require a test of the ocular pressures in that eye to rule out complications such as vision problems, glaucoma or blindness as a swollen port wine stain birthmark may create pressure on the eye. In infants with nevus flammeus birthmarks on the head or forehead, a MRI scan study of the brain may be necessary to rule out Sturge-Weber syndrome. |
| Image of nevus flammeus birthmark |
Port wine stain associated syndromes
Nevus flammeus birthmark is a cutaneous finding of several syndromes including Sturge-Weber syndrome, Klippel-Trenaunay syndrome, Parkes-Weber syndrome and Proteus syndrome.Nevus flammeus and carcinoma
Sirunya Silapunt et al. reported a case of basal cell carcinoma arising in a nevus flammeus birthmark in Dermatologic Surgery. A few cases of basal cell carcinoma developing in a port-wine stain birthmark have been reported in medical literature. The authors detected a nodular basal cell carcinoma on the margin of a previously untreated port-wine stain on the left cheek of an 87-year-old patient. The carcinoma was successfully excised and there was no evidence of recurrence of the tumor in the birthmark after twelve months. They concluded that,"basal cell carcinoma should be included in the differential diagnosis of a skin lesion occurring in a port-wine stain."
Nevus flammeus treatment
In the absence of successful treatment, increased tissue mass (hypertrophy), thickening and appearance of lumps in nevus flammeus birthmark may cause cosmetic, emotional and social problems and increasing disfigurement. The birthmarks near the eyelids and lips may impair their functions later in life. The treatment has to be started before one year of age. Early treatment, before thickening and hardening of the port wine stain birthmarks gives better results.A number of treatment options have been used with limited success in treating port wine stain birthmarks. Flashlamp-pumped pulsed-dye laser (PDL) surgery is considered as a treatment of choice for nevus flammeus birthmarks. PDL causes selective destruction of the capillary malformations by selective photothermolysis. PDL induces intravascular coagulation and rupture of smaller vessels in the nevus. Later the photothermolysis mass of cells in the port wine stain are absorbed and replaced by collagen.
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Reference: 1.Pasyk KA. Familial multiple lateral telangiectatic nevus (port-wine stain or nevus flammeus). Clin Genet. 1992 Apr;41(4):197-201. 2.Gao XH, Wang LL, Zhang L, Hong YX, Wei H, Chen HD. Familial nevus flammeus associated with early onset cherry angiomas. Int J Dermatol. 2008 Dec;47(12):1284-6. 3.Faurschou A, Olesen AB, Leonardi-Bee J, Haedersdal M. Lasers or light sources for treating port-wine stains. Cochrane Database Syst Rev. 2011 Nov 9;(11):CD007152. 4.Silapunt S, Goldberg LH, Thurber M, Friedman PM. Basal cell carcinoma arising in a port-wine stain. Dermatol Surg. 2004 Sep;30(9):1241-5. |
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