Endocrine studies in a pubertal male pseudohermaphrodite with 17-ketosteroid reductase deficiency

A 12 year old child (46,XY) with 17-ketosteroid reductase deficiency was investigated. The patient, reared as a female, was first noted to have clitoromegaly at 10 years of age. Increased facial hair, deepening of the voice, acne, increased body hair and minimal breast development were noted at 12 years. delta4-Androstenedione (delta4) in peripheral blood was markedly elevated (1913 ng/100 ml) whereas testosterone (T) was in the male range of Tanner III puberty (240 ng/100 ml). Thus, delta4/T in this patient was 9.4, compared to a normal ration of 0.15 to 0.25. T/DHT was normal (10.5). Oestrone (Oe1) level was slightly elevated (6 ng/100 ml, normal: 2.5-4.5 ng/100 ml). Oestradiol (Oe2) was normal (1.7 ng/100 ml, normal: 1.5-3 ng/100 ml. Oe1/Oe2 was slightly elevated (3.6, normal: 1-2). At laparotomy, testes were found and spermatic vein blood was obtained prior to castration. Androgen determinations of spermatic vein blood demonstrated extremely high delta4 levels (283 microgram/100 ml) and low levels of T (16 microgram/100 ml). delta4/T in spermatic vein was 17, higher than in the peripheral blood, suggesting intact peripheral conversion of delta4 to T. Incubation of testes slices with delta4 demonstrated severely impaired conversion to T. Conversion of Oe1 to Oe2 was impaired to a lesser degree.

17-ketosteroid reductase deficiency was documented in vivo by impaired conversion of precursor hormones resulting in higher than normal delta4T and Oe1/Oe2 ratios in blood. In vitro studies with testes slices confirmed the enzymatic defect.