17-Hydroxyprogesterone in normal children and congenital adrenal hyperplasia. Measurement in serum by radioimmunoassay after thin-layer chromatography.

Serum 17alpha-hydroxyprogesterone (17 OH-P) was measured by a specific radioimmunoassay technique combined with thin-layer chromatography. Normal values for children are less than 1.1 microgram/1 (less than 3.3 nmol/l)--corresponding to values found in the literature. In congenital adrenal hyperplasia (CAH) values up to several hundred microgram/l are found. The values rise after ACTH stimulation and are suppressed by decadrone or cortisone treatment. The rise in 17 ketosteroids and pregnanetriol in untreated CAH is relatively smaller (15--25 fold). This clinical sensitivity of 17 OH-P is thus valuable for the diagnosis of CAH (21 hydroxylase deficiency). Furthermore it is easier to take a blood sample than to collect urine for 24 hours. The usefulness in therapeutic monitoring is being studied.