[Lichen sclerosus at atrophicus. First observation on a boy's genitalia].

First report of a case of lichen sclerosus et atrophicus of the genitals in a twelve-year-old boy. The beginning of this disease at the time of the first growth of his pubic hairs coincides with the activity of the gonads, demonstrating apparently the influence of sexual hormones. The meaning of this factor is stressed by the fact that until now not a single case of lichen sclerosus et atrophicus at a boy's genitals has been published in the literature, in contrast to the relative frequency of this disease in girls. The chromosomal analysis of the buccal smear however revealed a chromatin negative result.