Congenital adrenal hyperplasia refers to a group of inherited disorders of the adrenal gland.
Adrenogenital syndrome; 21-hydroxylase deficiency
Causes, incidence, and risk factors
People have 2 adrenal glands, one located on top of each of their kidneys. These glands make hormones, cortisol and aldosterone, that are essential for life. People with congenital adrenal hyperplasia lack an enzyme the adrenal gland needs to make the hormones.
At the same time, the body produces more androgen, a type of male sex hormone. This causes male characteristics to appear early (or inappropriately).
Congenital adrenal hyperplasia can affect both boys and girls. About 1 in 10,000 to 18,000 children are born with congenital adrenal hyperplasia.
Symptoms will vary, depending on the type of congenital adrenal hyperplasia someone has and their age when the disorder is diagnosed.
- Children with milder forms may not have signs or symptoms of congenital adrenal hyperplasia and may not be diagnosed until as late as adolescence.
- Girls with a more severe form often have abnormal genitals at birth and may be diagnosed before symptoms appear.
- Boys will appear normal at birth even if they have a more severe form.
In children with the more severe form of the disorder, symptoms often develop within 2 or 3 weeks after birth.
- Poor feeding or vomiting
- Electrolyte changes (abnormal levels of sodium and potassium in the blood)
- Abnormal heart rhythm
Girls with the milder form will usually have normal female reproductive organs (ovaries, uterus, and fallopian tubes). They may also have the following changes:
- Abnormal menstrual periods or failure to menstruate
- Early appearance of pubic or armpit hair
- Excessive hair growth or facial hair
- Failure to menstruate
- Some enlargement of the clitoris
Boys with the milder form often appear normal at birth. However, they may appear to enter puberty early. Symptoms may include:
- Deepening voice
- Early appearance of pubic or armpit hair
- Enlarged penis but normal testes
- Well-developed muscles
Both boys and girls will be tall as children but much shorter than normal as adults.
Signs and tests
Your child's doctor will order certain tests. Common blood tests include:
- Serum electrolytes
X-ray of the left hand and wrist may show that the child's bones appear to be those of someone older than their actual age.
Genetic tests can help diagnose or confirm the disorder, but the are rarely needed.
The goal of treatment is to return hormone levels to normal, or near normal. This is done by taking a form of cortisol, most often hydrocortisone, three times per day. People may need additional doses of medicine during times of stress, such as severe illness or surgery.
The health care provider will determine the genetic sex of the baby with abnormal genitalia by checking the chromosomes (karyotyping). Girls with male-looking genitals may have surgery during infancy to correct the abnormal appearance.
Steroids used to treat congenital adrenal hyperplasia do not usually cause side effects, such as obesity or week bones, because the doses replace what the child cannot make. It is important for parents to report signs of infection and stress to your child's health care provider because the child may need more medication. Steroids cannot be stopped suddenly because doing so may lead to adrenal insufficiency.
- National Adrenal Diseases Foundation: www.nadf.us
- The MAGIC Foundation: www.magicfoundation.org
- The CARES Foundation: www.caresfoundation.org
People with this disorder must take medication their entire life. They usually have good health. However, they may be shorter than normal adults, even with treatment.
Congenital adrenal hyperplasia does not usually affect fertility.
- High blood pressure
- Low blood sugar
Parents with a family history of congenital adrenal hyperplasia (of any type) or a child who has the condition should consider genetic counseling.
Prenatal diagnosis is available for some forms of congenital adrenal hyperplasia. Diagnosis is made in the first trimester by chorionic villus sampling. Diagnosis in the second trimester is made by measuring hormones such as 17-hydroxyprogesterone in the amniotic fluid.
A newborn screening test is available for the most common form of congenital adrenal hyperplasia. It can be done on heelstick blood (as part of the routine screenings done on newborns). This test is currently performed in most states.
White PC. Congenital adrenal hyperplasia due to 17-hydroxylase deficiency. In: Kliegman RM, Stanton BF, St. Geme J, Schor N, Behrman RE. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 570.