Induction of Darier's disease by repeated irradiation by ultraviolet B; protection by sunscreen and topical ascorbic acid.

Darier's disease, keratosis follicularis, is frequently aggravated by sun exposure. Although there have been reports of Darier's disease reproduced by repeated exposure to ultraviolet B, little is known about its photo-protection. We artificially induced Darier's disease in a 47-year-old Korean man, and tested the protection afforded by sunscreen and topical ascorbic acid. Complete lesions of Darier's disease arose with repeated exposure of ultraviolet B (2,600 mJ/cm2 for 10 days), and sunscreen and topical ascorbic acid protected against its appearance. This result strongly suggests that sunscreen and ascorbic acid would be very helpful in preventing the aggravation of Darier's disease caused by sun exposure.