Sexual precocity in a 2-year-old boy caused by indirect exposure to testosterone cream.

OBJECTIVE To report a rare case of sexual precocity caused by inadvertent exposure to testosterone cream. METHODS We report the clinical, laboratory, and radiologic findings of a boy presenting with sexual precocity; review short- and long-term consequences; and discuss preventative measures. RESULTS A 2 and 7/12-year-old boy had onset of pubic hair without testicular enlargement and a period of rapid linear growth. History revealed possible topical testosterone exposure from close contact with the child's father. On physical examination, the boy had Tanner stage II pubic hair distribution. Laboratory evaluation findings were normal for age except for the testosterone concentration, which was comparable to late-pubertal and adult male levels at 371 ng/dL (reference range, <3-10 ng/dL for prepubertal male). Brain magnetic resonance imaging and testicular ultrasonography were normal. Skeletal age was advanced at age 4 and 6/12 years. Repeated laboratory evaluation, after the child's father ceased testosterone use, revealed a normal testosterone concentration of 10 ng/dL. Thus, this boy's sexual precocity was attributed to inadvertent exogenous androgen exposure. CONCLUSIONS When examining a child with sexual precocity, asking about possible exposure to androgens and estrogens is important. Patients being treated with these products should be educated about the possible risks of testosterone exposure to others and ways to limit exposure.