How common is congenital adrenal hyperplasia?
The severe form, “classic” forms of CAH occur in 1 in 10,000 to 1 in 15,000 births worldwide. Milder forms of CAH are much more common. The various forms of CAH are described below. Classic CAH-21-hydroxylase deficiency: Lack of both cortisol and aldosterone predispose 3/4 of severely affected individuals to “adrenal crises” with dehydration and shock, or even death, if not properly diagnosed and treated. For this reason, most states in this country now perform newborn screening for CAH. Excess adrenal androgen production begins in early fetal life in classic CAH-21 affected infants, and causes abnormal growth of girls’ clitoris and masculinization of the genital-urinary structures. Severely affected girls may be mistaken for boys at birth. Affected boys have no genital malformations at birth, but continued androgen excess causes unusually fast body growth. Inappropriately early puberty leads to premature completion of growth and short adult height. Proper medical treatment resets the
