Congenital adrenal hyperplasia (CAH) refers to a group of genetic disorders that affect the adrenal glands, a pair of walnut-sized organs above the kidneys. The adrenal glands produce important hormones, including:
In people who have CAH, a genetic problem results in a lack of one of the enzymes needed to make these hormones.
Although there is no cure, with proper treatment, most people who have congenital adrenal hyperplasia can lead normal lives.
There are two major types of congenital adrenal hyperplasia:
Signs and symptoms of CAH vary, depending on which gene is defective and the level of enzyme deficiency.
Female infants who have classic CAH may have a condition known as ambiguous genitalia, in which the clitoris is enlarged or the genitals look more like those of a male child. Male infants who have classic CAH have normal appearing genitals. Both male and female infants can be seriously affected by a lack of cortisol, aldosterone or both. This is known as an adrenal crisis, and it can be life-threatening.
The salt-losing form and simple-virilizing form of classic CAH cause children's bodies to produce an insufficient amount of cortisol. These children can have problems maintaining normal blood pressure, normal blood sugar and energy levels, and are more vulnerable to stress. An excess of the male sex hormones can result in short height and early puberty for both boys and girls.
Signs and symptoms of classic CAH in children and adults include:
Often there are no symptoms of nonclassic CAH when a baby is born. The condition is not identified on routine infant blood screening and usually becomes evident in late childhood or early adulthood. Cortisol may be the only hormone that's deficient.
Teenage and adult females who have nonclassic CAH may have normal appearing genitals at birth, but later in life, they may experience:
In both females and males, signs of nonclassic CAH may also include:
Classic CAH is usually detected at birth through required newborn screening or when female babies have ambiguous genitalia. CAH may also be identified when male or female babies show signs of severe illness due to low levels of cortisol, aldosterone or both.
In children who have nonclassic CAH, signs and symptoms of early puberty may appear. If you have concerns about your child's growth or development, make an appointment with your child's doctor.
If you are pregnant and may be at risk of CAH because of your own medical history or your ethnicity, ask your doctor about genetic counseling.
The most common cause of CAH is the lack of the enzyme known as 21-hydroxylase. CAH may sometimes be called 21-hydroxylase deficiency. There are other much rarer enzyme deficiencies that also cause CAH.
Children who have the condition have two parents who either have CAH themselves or who are both carriers of the genetic mutation that causes the condition. This is known as the autosomal recessive inheritance pattern.
Factors that increase the risk of having CAH include:
People who have classic CAH are at risk of adrenal crisis because they have very low levels of cortisol in the blood. This can cause diarrhea, vomiting, dehydration, low blood sugar levels and shock. Adrenal crisis is a life-threatening medical emergency that requires immediate treatment. Aldosterone also may be low, which leads to dehydration and low sodium and high potassium levels. The nonclassic form of CAH doesn't cause adrenal crisis.
Males and females who have either classic or nonclassic CAH may also experience fertility problems.
There is no known way to prevent congenital adrenal hyperplasia. If you're thinking of starting a family and you're at risk of having a child with CAH, your doctor may recommend that you see a genetic counselor.
CAH may be diagnosed before a baby is born, during childhood or later in life.
Tests used to diagnose CAH in fetuses include:
Doctors recommend that all newborns in the United States be screened for genetic 21-hydroxylase deficiency during the first few days of life. This test identifies the classic form of CAH but doesn't identify the nonclassic form.
Diagnosis of CAH in older children and young adults includes:
Your doctor will likely refer your child to a doctor who specializes in childhood hormonal issues (pediatric endocrinologist) for treatment of CAH. The health care team may also include other specialists, such as urologists, psychologists and geneticists.
The goal of treating CAH with medications is to reduce excess androgen production and replace deficient hormones. People who have the classic form of CAH can successfully manage the condition by taking hormone replacement medications throughout their lives. People who have nonclassic CAH may not require treatment or may need only small doses of corticosteroids.
Medications for CAH are taken on a daily basis. During periods of illness or significant stress, such as surgery, additional medications or higher doses may be needed.
Medications may include:
Monitoring the effectiveness of medication includes regularly scheduled:
In some female infants who have severe ambiguous genitalia as a result of classic CAH, doctors may recommend reconstructive surgery to improve genital function and make them look more feminine.
Surgery may involve reducing the size of the clitoris and reconstructing the vaginal opening. The surgery is typically performed between 2 and 6 months of age. Females who have reconstructive genital surgery may need more cosmetic surgery later in life.
Genital surgery is easier to perform when a child is very young. However, some parents choose to wait for surgery until their child is old enough to understand the risks and choose his or her own gender assignment.
Before making decisions about the best treatment approach for your child, talk with your doctor about these issues. Working together, you and your doctor can make informed choices that will help your child thrive.
Psychological support is important to the emotional health and social adjustment of female children who have genital abnormalities.
Synthetic corticosteroids that cross the placenta to the fetus are controversial and considered experimental. More research is needed to determine the long-term safety and the effect of this treatment on fetal brain development.
Early and steady support from family and health care professionals can help your child have normal self-esteem and a satisfying social life. These approaches may help:
You may start by seeing your family doctor or your child's pediatrician. He or she may refer you to a doctor who specializes in the diagnosis and treatment of conditions related to the adrenal glands (pediatric endocrinologist).
Here's some information to help you prepare for your appointment. Consider taking a family member or friend along for support and to help you remember information.
To prepare for your appointment:
Some basic questions to ask your doctor may include:
Don't hesitate to ask any other questions during your appointment.
Your doctor is likely to ask you a number of questions. Be ready to answer them to reserve time to go over points you want to focus on. For example, your doctor may ask:
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