17 alpha-hydroxylase deficiency syndrome associated with bilateral streak gonads and impaired development of Müllerian ducts derivatives. Report of a case.

We report severe 17 alpha-hydroxylase deficiency in a 17 year-old black girl with 46,XX genotype. The diagnosis was suspected because of primary amenorrhoea, absence of sexual maturation, hypertension and hypokalaemia with renal potassium wasting. Endocrine investigation revealed low basal levels of all steroid hormones which require 17 alpha-hydroxylation for biosynthesis (i.e. glucocorticoids, androgens and oestrogens). No increase in their basal levels was seen following adrenal stimulation, indicating a severe block. Plasma concentrations of ACTH, FSH and LH were elevated as were progesterone, 11-deoxycorticosterone and corticosterone. Plasma renin activity was suppressed and aldosterone levels were very low. After 4 months of glucocorticoid replacement therapy, aldosterone was still low, even though the suppression was otherwise effective. Our case is unusual because bilateral streak gonads and impaired development of Müllerian ducts derivatives were also present. To our knowledge, a similar case has never been reported before.