Incomplete virilization and subclinical mineralocorticoid excess in a boy with partial 17,20-desmolase/17 alpha-hydroxylase deficiency.

A 17-year-old boy is described with impaired virilization and subclinical mineralocorticoid excess owing to combined 17,20-desmolase/17 alpha-hydroxylase deficiency. His basal plasma progesterone was 20.9 nmol/l (reference value 0.50-1.88), 17-hydroxyprogesterone 21.3 nmol/l (reference value 3.05-4.84), testosterone 6.85 nmol/l (reference value 14.1-22.0), and his excretion of tetrahydro-11-deoxycorticosterone 11.8 mumol/24 h (reference value 1.0-1.5). The differential effects of this combined enzyme deficiency on adrenal and testicular function were studied by ACTH stimulation, dexamethasone suppression, hCG stimulation, and suppression treatment with testosterone.