17-hydroxyprogesterone (17OHP) is a biomarker for congenital adrenal hyperplasia (CAH).
CAH results from a defect in the metabolic pathway for the production of steroid hormones, most importantly cortisol and aldosterone. The most common enzyme deficiency is 21-hydroxylase deficiency which accounts for approx. 95% of cases. CAH presents on a continuum depending on the residual enzyme activity with the most severe form presenting in infancy with a potential life threatening salt-wasting crisis (hyponatraemia, hyperkalaemia and adrenal insufficiency - low cortisol). Other presentations include varying degrees of virilisation of the female infant or precocious puberty in the male due to shifting the flux of hormone production to androgens.
Less severe forms of CAH may not present until later in life with symptoms of hirsutism or oligomenorrhea (irregular menstruation).
17OHP may be requested as a screening test for CAH or following stimulation by Synacthen (ACTH).
Endocrinology Lab
OHPR
17 hydroxyprogesterone
14 days
8049