Erythema dyschromicum perstans. A follow-up study from northern Finand.

Four patients with ashy dermatosis are described. Their ages varied from 8 to 12 years. Three had typical widespread macular eruptions and one had a linear lesion not described before. The follow-up investigation revealed that the eruption disappeared within 2 years in three of the patients. One patient could not be followed. The duration of the disease and the linearity of one lesion resembled lichen ruber planus.