Congenital Adrenal Hyperplasia Due to Steroid 21-Hydroxylase Deficiency: An Endocrine Society* Clinical Practice Guideline

Newborn screening Cost-effectiveness 1.1 We recommend that all newborn screening programs incorporate screening for congenital adrenal hyperplasia due to 21-hydroxylase deficiency. (1|s) 1.2 We recommend that first-tier screens use 17hydroxyprogesterone assays standardized to a common technology with norms stratified by gestational age. (1|s) Technical remark: Clinicians should be aware that immunoassays are still in use and remain a source of false-positive results. Specificity may be improved with organic extraction to remove cross-reacting substances. 1.3 We recommend that screening laboratories employ a second-tier screen by liquid chromatographytandem mass spectrometry in preference to all other