Radioimmunoassay of blood-spot 17 alpha-hydroxyprogesterone in the management of congenital adrenal hyperplasia.
A robust assay for routine measurement of blood-spot 17 alpha-hydroxyprogesterone (17-OHP) concentrations has been developed using a magnetizable, solid-phase antiserum and an 125I-radioligand. The working range of this assay (13.5-500 nmol/L) is well suited for the initial diagnosis of congenital adrenal hyperplasia (CAH) and for monitoring replacement therapy in CAH patients. Data derived from multiple blood-spot samples, collected on two consecutive days, provide 17-OHP profiles. These profiles have been used to construct a chart allowing a rapid visual assessment of the efficacy of replacement therapy in CAH patients. Measurement of 17-OHP in the blood-spots of overtreated patients and accurate determination of normal range values in healthy infants relied on development of a sensitive assay (range 1.7-34 nmol/L). In the blood-spots of normal male (n = 50) and female (n = 50) infants collected 5-7 days after birth, 17-OHP concentrations were 7.62 +/- 2.55 nmol/L and 7.32 +/- 2.87 nmol/L respectively. Retrospective measurement of this steroid in samples from known CAH patients (n = 4), which had values ranging from 224 to 2145 nmol/L, support a role for measurement of blood-spot 17-OHP in high-risk screening programmes.
D019326:17-alpha-Hydroxyprogesterone; D000312:Adrenal Hyperplasia, Congenital / Q000097:blood*; D001800:Blood Specimen Collection; D002648:Child; D005260:Female; D006801:Humans; D006908:Hydroxyprogesterones / Q000097:blood*; D007231:Infant, Newborn; D008297:Male; D008403:Mass Screening; D011863:Radioimmunoassay; D012189:Retrospective Studies; D012306:Risk; D012463:Saliva / Q000032:analysis
D006908:Hydroxyprogesterones; D019326:17-alpha-Hydroxyprogesterone