17 alpha hydroxyprogesterone (17OHP)

General Information

17alpha-Hydroxyprogesterone is an intermediate in the biosynthesis of cortisol. Deficiency of either 11- or 21-hydroxylase activities leads to an increased concentration of 17alpha-hydroxyprogesterone in the peripheral circulation. This test is less valuable in 11-hydroxylase deficiency, where 11-deoxycortisol is the analyte of choice. 'Functional' deficiencies of 21-hydroxylase and 11-hydroxylase have been described. Indications: a) Diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency. b) Monitoring the response to corticosteroid therapy in congenital adrenal hyperplasia due to 21-hydroxylase deficiency. 3) Identification of heterozygotes for congenital adrenal hyperplasia and diagnosis of mild congenital adrenal hyperplasia (also referred to as late-onset and cryptic forms).