Systematized porokeratotic eccrine and hair follicle naevus: report of a case and review of the literature

We report a unique case of a congenital keratinocytic naevus associated wit h severe alopecia, onychodysplasia and palmoplantar involvement in a 13-yea r-old girl, The lesions, consisting of scaly, spinous and verrucous papules and plaques, mainly followed Blaschko's lines and have remained unchanged since birth, The predominant histopathological picture was that of a column of parakeratosis overlying the eccrine ostia and hair follicles, This is t he first case of a systematized keratinocytic naevus characterized by histo pathology of eccrine and hair follicle porokeratosis and a widespread bilat eral involvement. This may be a distinct entity to be included in the diffe rential diagnosis of linear, hyperkeratotic dermatoses, We suggest its clas sification as systematized porokeratotic eccrine and hair follicle naevus.