non classic 21 hydroxylase deficient adrenal hyperplasia in patients with isolated precocious pubarche

precocious pubarche (pp) is most often a benign condition secondary to the early appearance of adrenarche. however, pp may be a manifestation of mild errors of steroidogenesis in particular non classic 21 hydroxylase deficiency (nc210hd). the incidence of nc210hd in patients with pp ranges from about 0-30% of cases in various reports. controversy exists as to whether all children with pp should undergo an acth test. this study was designed in order to determine 1) the frequency of nc210hd in children with isolated pp 2) to determine whether basal 17 hydroxyprogestrone (17ohp) values could help distinguish patients who are at risk for having nc210hd and thus should have an acth test. we studied 54 subjects (38 girls and 16 boys) aged 6.5±1.4 yr with isolated pp. twenty five normal subjects (10 age matched and 15 pubertal) were studied as controls. blood samples were drawn at baseline for dehydro-epiandrosterone (dhea), androstendione (a), and 17α-hydroxy progesterone (17ohp). an acth stimulation test (synacthen 0.25 mg iv bolus) was performed and 1 hr post injection 17ohp was evaluated. bone age was determined in all subjects. using published normogram standards for the serum 17ohp response to acth, 3 patients (5.5%) were diagnosed as having nc210hd. in all patients diagnosed as having nc210hd, basal 170hp level was higher than pubertal value. thus, from a clinical point of view, the acth test in patients with typical pubarche must be reserved for subjects with high basal 170hp levels. our experience adds to the current logic that men with azoospermia or severe oligospermia should be evaluated for yq11 microdeletions before deciding to operate varicoceles or else scheduling them for assisted reproductive techniques.