Male pseudohermaphroditism due to 17 alpha-hydroxylase deficiency: diagnosis by gas chromatography--mass spectrometry.

A case of male pseudohermaphroditism associated with 17 alpha-hydroxylase deficiency is reported in which the diagnosis was firmly established by gas chromatography-mass spectrometry. The patient was a 20-year-old genotypic male, phenotypic female who presented with primary amenorrhea, absence of body hair, and no breast development. She was hypertensive. Corticosterone and progesterone levels were very high and sex steroids were virtually absent. Gonadotropins were in the menopausal range. The results of radioimmunoassay were not diagnostic. Analysis of urine using gas chromatography-mass spectrometry revealed a striking absence of steroids with 17-oxygen function-nor were there any 18 or 19 carbon steroids. These results clearly establish a total deficiency of 17 alpha-hydroxylase activity.