Transient central precocious puberty in non-classic 21-hydroxylase deficiency.

A seven year-old boy with non-classic 21-hydroxylase deficiency had transient hormonal evidence of central precocious puberty within three months of beginning glucocorticoid treatment for rapidly progressive somatic virilization. Adrenal-derived sex hormones were normalized promptly by hydrocortisone treatment. GnRH-stimulated LH levels and basal testosterone returned to the prepubertal range without further intervention after six months of glucocorticoid therapy. This is the first report of transient central precocious puberty in the mild non-classic form of congenital adrenal hyperplasia due to 21-hydroxylase deficiency.