Cutaneous: linear vesicobullous lesions at birth, rarely as late as 1 year. Lesions change to linear verrucous and dyskeratotic growth. Pigmentary changes follow: slate-gray blue or brown, irregular marbled or wavy lines; later fade to depigmented, atrophic skin. Skin lesions in lines of Blaschko.

Neurologic (20%): slow motor development, spastic hemiparesis, quadriparesis, or diplegia; mental retardation; seizures.