Screening for late onset congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

Basal and post-ACTH levels of 17 alpha hydroxy-progesterone (17 OHP) were determined in 53 subjects with hirsutism. Late onset congenital adrenal hyperplasia (LOCAH) was detected in five (10.6%) on the basis of elevated basal and/or ACTH stimulated levels of 17 OHP. Of the five patients, two were considered to have a heterogygous state on account of a small rise in stimulated 17 alpha OHP. Screening tests for LOCAH are essential as the clinical diagnosis is not otherwise possible for this treatable and often familial disorder.