Disseminated superficial porokeratosis in patients with pemphigus vulgaris treated with steroids.

In two patients with pemphigus vulgaris a rash identical with that seen in disseminated superficial porokeratosis developed on the trunk and extremities during periods in which they were receiving relatively high doses of steroids. Some time after reduction of the daily dose or discontinuance of treatment this rash disappeared. In one patient, however, this rash subsequently recurred twice, both times after reinstitution of treatment because of the reappearance of pemphigus lesions. It is suggested that disseminated superficial porokeratosis should be added to the list of possible skin eruptions developing as the result of the systemic use of corticosteroids at a high dose for a prolonged period of time, although the mechanism of its appearance in these cases is not yet clear.