Detection of late onset steroid 21-hydroxylase deficiency by capillary gas chromatographic profiling of urinary steroids in children and adolescents.

Patients suffering from late onset 21-hydroxylase deficiency (LO-CAH) excreted only slightly higher amounts of 17-hydroxypregnanolone (17-OH-PO), pregnanetriol (PT) and 11-oxo-pregnanetriol (11-O-PT) than age-matched healthy controls. To discriminate between LO-CAH and virilization of unknown origin and precocious pubarche, we calculated the following ratios: (1) pregnanetriol to tetrahydrocortisone (PT/THE), (2) the sum of 17-OH-PO, PT and 11-O-PT (OHP-M) to the sum of THE, tetrahydrocortisol (THF) and allotetrahydrocortisol (a-THF) (C-M) and (3) 11-O-PT to C-M. The following patients were studied: 9 patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency-non-salt losing (CAH-NSL), never treated; 8 patients with CAH (NSL/SL: 3/5) off treatment; 10 patients with LO-CAH; 11 patients with virilization of unknown origin (prepubertal/pubertal: 5/6) and 9 patients with precocious pubarche. Healthy individuals and obligatory heterozygote carriers of comparable ages served as controls. LO-CAH showed increased ratios (median (range] of PT/THE: 2.27, (1.15-9.09), OHP-M/C-M: 2.30, (1.24-8.15), and 11-O-PT/C-M: 0.24, (0.13-1.23) compared to healthy individuals and heterozygous carriers: PT/THE 0.28, (0.03-0.57), OHP-M/C-M 0.23, (0.06-0.46) and 11-O-PT/C-M less than 0.01, (less than 0.01-0.06), respectively. The calculation of ratios, rather than absolute amounts seems to allow the detection of LO-CAH in a single spontaneously voided urine specimen. The clinical and measurable hormonal manifestations of LO-CAH occur at the same time.