Diagnosis and natural history of 17-hydroxylase deficiency in a newborn male.

We documented 17-hydroxylase deficiency in a newborn male infant with micropenis, perineoscrotal hypospadias, and a bifid scrotum containing two histologically normal testes. Mild hypertension developed at 20 months of age. The diagnosis was made on the basis of elevated serum levels of progesterone (180-475 ng/dl), corticosterone (1.8-20.2 micrograms/dl), and desoxycorticosterone (56-330 ng/dl). There was an exaggerated response of these steroids to ACTH-(1-24) and suppression by dexamethasone. Mass spectrometric analysis of urinary steroids showed an abnormally high ratio of C21 to C19 3 beta-hydroxy-5-ene steroids due to reduced C19 steroid formation. We suggest that this infant has a form of 17-hydroxylase deficiency which is less severe than previously reported cases in view of his partial prenatal virilization, the minimal testosterone response to CG the absence of hypokalemia, and the presence of normal cortisol levels after prolonged ACTH stimulation. Family studies suggest reduced 17-hydroxylase activity in the father. A surprising coincident finding of no apparent clinical significance was in vitro evidence of 5 alpha-reductase deficiency in genital skin fibroblasts.