Congenital Adrenal Hyperplasia (CAH) refers to a complex series of rare but well-studied enzymatic errors of metabolism with deficient levels of different enzymes involved in the synthesis of cortisol (hydrocortisone).
CAH comprises a group of disorders resulting from defective synthesis of adrenal corticosteroids. Lack of glucocorticoids, especially cortisol, causes various kinds of metabolic problems. The response to low levels of cortisol is increased production of corticotropin (ACTH). Lack of mineralocorticoids, primarily aldosterone (steroid hormone), causes sodium and water imbalance which, in some cases, can be fatal. The various forms of CAH represent defects in the different stages of corticosteroid synthesis, usually hydroxylation reactions at certain positions on the original
CAH is a family of inherited disorders affecting the adrenal glands. The most common form is 21-hydroxylase deficiency (21-OHD), which is inherited in severe or mild forms. The severe form, called Classical CAH, is usually detected in the newborn period or in early childhood. The milder form, called Non-classical CAH (NCAH), may cause symptoms at anytime from infancy through adulthood. NCAH is a much more common disorder than Classical CAH. Fortunately, CAH can be managed with medication and, with adequate care, affected individuals go on to live normal lives. CAH is an autosomal recessive genetic disorder. It affects males and females in equal numbers. For a child to be born with either form of CAH, both parents must carry a gene for the disorder (see Figure 1). Scientists have pinpointed the location of the group of genes that causes the most common forms of CAH to chromosome 6. DNA testing is available for diagnosis of CAH and to detect carriers of the gene mutations.
These particular groups of genes contain instructions the adrenal glands (located on top of the kidneys) need in order to produce an enzyme called 21-hydroxylase. Without this