Verrucous epidermal nevus
Nevus unius lateris
Verrucous epidermal nevi are cutaneous hamartomas composed predominantly of keratinocytes. They appear to be somatic mutations, and usually occur along Blashko's lines.
While usually present at birth, they may not become apparent until adulthood.
They can be small ( 1-2 centimeters), or very extensive covering most of the skin surface.
Morphologically they are well demarcated, brown and raised. Parts may look "warty".
Once developed they tend to be relatively stable.
Extensive epidermal nevi can be a component of various genodermatoses.
Inflammatory linear verrucous epidermal nevus (ilven)
Inflammatory epidermal nevi usually develop early in life, typically before age six.
There is an eruption of linear eczematous or psoriasiform papules.
Lesions can follow Blashko's lines.
There may be a severe associated pruritus.
It differs from lichen striatus in that lichen striatus is generally not pruritic, and lichen striatus spontaneously remits.
- Cryotherapy can be successful, but the treatment of choice for small lesions is surgical removal, including the underlying dermis.
- The hyperkeratotic component may respond partially to topical lactic acid 5-15% creams.
- However, the fundamental abnormality of the keratinocytes is cured only by surgical removal. Such removal would include carbon dioxide laser ablation of the lesion, with thorough destruction of the dermis.
- Unless the underlying dermis is removed, recurrence is very likely.