Inflammatory linear verrucous epidermal naevus (ILVEN)

An inflammatory linear verrucous epidermal naevus (ILVEN) is an inflamed and itchy variant of an epidermal naevus. 

This chapter is set out as follows:  

• Age - 75% of lesions arise during the first five years of life, most often in the first six months
• Can be very itchy

Distribution

• Most commonly a single lesion that arises along Blaschko's lines, especially on the legs - refer to the related chapter 
• Occasionally bilateral and more extensive 

Morphology

• Linear and of variable length 
• Eczematous or psoriasiform papules

Differential diagnosis

• ​Lichen striatus can be distinguished by the following:
• Rapid development
• Age - most present over the age of one year, although some develop in infancy
• Lack of itch
• Spontaneous evolution, within 3-6 months for the majority 

• Other dermatoses involving Blaschko's lines eg naevoid psoriasis 

• Many treatments have been tried but results are often disappointing:
• Potent topical steroids and intralesional steroids may give temporary relief
• Cryotherapy has been used for smaller lesions
• Laser can give a temporary clearance 

• Unlike with lichen striatus, spontaneous resolution is uncommon