Congenital adrenal hyperplasia
DEFINITION
Congenital adrenal hyperplasia (kun-JEN-ih-tul uh-DREE-nul hi-pur-PLAY-zhuh) is a collection of genetic conditions that limit your adrenal glands’ ability to make certain vital hormones. In most cases of congenital adrenal hyperplasia, the adrenal glands don’t produce enough cortisol. The production of two other kinds of hormones also may be affected, including mineralocorticoids (for example, aldosterone) and androgens (for example, testosterone).
Congenital adrenal hyperplasia can cause problems with normal growth and development in children — including normal development of the genitals. It affects both males and females.
Although congenital adrenal hyperplasia can be life-threatening, most people with it can lead normal lives with proper treatment.
CAUSES
Congenital adrenal hyperplasia affects your adrenal glands, a pair of walnut-sized organs located above your kidneys.
Inherited defect affects cortisol production
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.
A child with classic congenital adrenal hyperplasia may also experience:
- A lack in the adrenal glands’ production of aldosterone.This can lead to low blood pressure, lower sodium level and higher potassium level. Sodium and potassium normally work together to help maintain the right balance of fluids in your body, transmit nerve impulses, and contract and relax your muscles.
- Excess production of the male sex hormones (androgens such as testosterone). This can result in short height, early puberty in boys, abnormal genital development in girls and severe acne. Signs and symptoms may vary, depending on which specific gene is defective.
- The condition is passed along in an inheritance pattern called autosomal recessive. Children who have the disorder have two parents who either have the condition themselves or who are both carriers of the genetic mutation that causes the condition.
SYMPTOMS
There are two major types of congenital adrenal hyperplasia:
- Classic congenital adrenal hyperplasia. This more severe form of the disease is usually detected in infancy or early childhood.
- Nonclassic congenital adrenal hyperplasia. This milder form usually becomes evident in late childhood or early adulthood.
- Classic congenital adrenal hyperplasia
- The most obvious sign of classic congenital adrenal hyperplasia in girls is often abnormal-appearing genitals that look more male than female, which may include an enlarged clitoris — a condition called ambiguous external genitalia. Other signs and symptoms in girls also reflect exposure to higher levels of male sex hormones (androgens) while in the womb.
- The condition is not typically as easily seen in baby boys, although some affected male infants have an enlarged penis.
- Signs and symptoms of classic congenital adrenal hyperplasia in infants include:
- Ambiguous genitalia in girls
- Enlarged penis in boys
- Poor weight gain
- Weight loss
- Dehydration
- Vomiting
Signs and symptoms of classic congenital adrenal hyperplasia in children and adults include:
- Very early puberty
- Rapid growth during childhood, but shorter than average final height
- Irregular menstrual cycles in women
- Infertility in women and men
- Nonclassic congenital adrenal hyperplasia
- This form of congenital adrenal hyperplasia is milder and usually becomes evident in late childhood or early adulthood.
Signs and symptoms are typically most apparent in adolescent girls and women and often include:
- Irregular or absent menstrual periods
- Masculine characteristics such as facial hair, excessive body hair and a deepening voice
- Infertility
In both females and males, signs and symptoms of nonclassic congenital adrenal hyperplasia also may include:
- Early puberty
- Rapid growth during childhood, but shorter than average final height
- Severe acne
- Low bone density
- Obesity
When to see a doctor
Contact your child’s pediatrician if your child has signs and symptoms that seem to suggest congenital adrenal hyperplasia. Also, if you’re pregnant and may be in a high-risk group for congenital adrenal hyperplasia because of your own medical history or your ethnicity, ask your doctor about genetic counseling. Your doctor can also discuss with you possible treatment of your fetus before birth (prenatal treatment).
