Adrenal Hyperplasia (Congenital)

Definition

Definition of Adrenal Hyperplasia (Congenital)
Congenital adrenal hyperplasia (CAH) refers to any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of cortisol from cholesterol by the adrenal glands (steroidogenesis). CAH is one of the possible underlying synthesis problems in Addison’s disease. CAH is a genetic disorder in which girls are masculinized because the adrenal glands secrete large amounts of androgen during prenatal development. The extra androgen does not affect a baby boy's physical development, but in baby girls it can enlarge the clitoris so that it resembles a penis. The girls sometimes have surgery during infancy to correct their physical appearance, although this practice is highly controversial, and they can receive hormone therapy to correct the imbalance of androgen. During childhood and adolescence, girls with CAH prefer masculine activities and male playmates to a much greater extent than girls not exposed to these amounts of androgen.

There are two major types of congenital adrenal hyperplasia:

1. Classic congenital adrenal hyperplasia. This more severe form of the disease is usually detected in infancy or early childhood.
2. Nonclassic congenital adrenal hyperplasia. This milder form usually develops in late childhood or early adulthood.

Symptoms

Symptoms of Adrenal Hyperplasia (Congenital)
Signs and symptoms of classic congenital adrenal hyperplasia in infants include:

1. Ambiguous genitalia in girls
2. Enlarged penis in boys
3. Poor weight gain
4. Weight loss
5. Dehydration
6. Vomiting

Causes

Causes of Adrenal Hyperplasia (Congenital)
Congenital adrenal hyperplasia affects your adrenal glands, a pair of walnut-sized organs located above your kidneys.

The cause of congenital adrenal hyperplasia is an inherited genetic defect that limits production of one of the many enzymes the adrenal glands use to make cortisol. The enzyme most commonly lacking in congenital adrenal hyperplasia is 21-hydroxylase. Congenital adrenal hyperplasia may sometimes be called 21-hydroxylase deficiency. Signs and symptoms of congenital adrenal hyperplasia are worst when the enzyme deficiency is severe.

Most of the problems caused by classic congenital adrenal hyperplasia are related to a lack of cortisol, which plays an important role in regulating your blood pressure, maintaining blood sugar and energy levels, and protecting your body against stress.

Diagnosis

Diagnosis of Adrenal Hyperplasia (Congenital)
The diagnosis of CAH has traditionally rested on hormone measurements combined with clinical evaluation, including history and physical examination. Most states in the U.S. as well as several foreign countries now perform a hormonal test for CAH within the first few days of life. These heel-prick blood specimens are obtained at the time when blood is drawn for thyroid tests and a number of other inherited diseases.

The rationale for newborn screening is that mainly in boys, who have no outward sign of the disease, the mortality from "adrenal crisis" is high, and this could be entirely prevented by early diagnosis and medical treatment. Since the incidence of classical CAH worldwide is about 1 in 5,000 male births (or 1 in 15,000 total births), this amounts to a substantial number of potentially preventable infant deaths. These screening programs have achieved their goals. Diagnostic methods are continually being refined, both for the hormonal methods, and for the newer genetic typing discussed below.

Since the advent of molecular genetic technology, we can now examine the genes of CAH patients and family members. This type of study has application for prenatal testing, neonatal screening, and genetic counseling, as well as confirming diagnosis in questionable cases. Molecular diagnosis is available in several specialized laboratories. Families should receive genetic counseling in conjunction with genetic testing, if they choose this procedure.

Treatment

Treatment of Adrenal Hyperplasia (Congenital)
Treatment of all forms of CAH may include any of:

1. supplying enough glucocorticoid to reduce hyperplasia and overproduction of androgens or mineralocorticoids
2. providing replacement mineralocorticoid and extra salt if the person is deficient
3. providing replacement testosterone or estrogen at puberty if the person is deficient
4. additional treatments to optimize growth by delaying puberty or delaying bone maturation

Prognosis

Prognosis of Adrenal Hyperplasia (Congenital)
Consult with your doctor.

Prevention

Prevention of Adrenal Hyperplasia (Congenital)
Doctors often recommend genetic counseling for parents who have congenital adrenal hyperplasia and are contemplating starting a family. The disorder can be diagnosed in fetuses, and prompt treatment, most often beginning in the first or second trimester, can reduce or even eliminate symptoms after birth.