Sexual development in a two-year-old boy induced by topical exposure to testosterone.

Virilization, including penile enlargement and growth of pubic hair and facial acne, developed in a 2-year-old boy over a period of months. This sexual development was induced by incidental and unintentional dermal exposure to a testosterone cream that was applied to his father's arm and back as a part of body building regimen. Except for penile size, the other signs of virilization diminished several months after the exposure was discontinued.