[A patient with Ito's hypomelanosis, also called incontinentia pigmenti achromians].

A 2 1/2 year old mentally retarded Dutch boy, suffering from epilepsy, hydrocefalus, generalised hypotonia, degenerative signs of the eyes and teeth and characteristic pigment disturbances of the skin is described. The complete picture fits in the syndrome of Ito's hypomelanosis, also called incontinentia pigmenti achromians. This is a neurocutaneous syndrome or an ectodermal dysplasia.