Update on diagnosis and management of congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Purpose of review Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is a relatively common inherited disorder of cortisol biosynthesis that can be fatal if untreated. Recent findings The basic biochemistry and genetics of CAH have been known for decades but continue to be refined by the discoveries of an alternative 'backdoor' metabolic pathway for adrenal androgen synthesis and the secretion of 11-hydroxy and 11-keto analogs of known androgens, by the elucidation of hundreds of new mutations, and by the application of high-throughput sequencing techniques to noninvasive prenatal diagnosis. Although hydrocortisone is a mainstay of treatment, overtreatment may have adverse effects on growth, risk of obesity, and cardiovascular disease; conversely, undertreatment may increase risk of testicular adrenal rest tumors in affected men. Summary Refinements to screening techniques may improve the positive predictive value of newborn screening programs. Alternative dosing forms of hydrocortisone and additional therapeutic modalities are under study. Although surgical treatment of virilized female genitalia is widely accepted by families and patients, it is not without complications or controversy, and some families choose to defer it.