Congenital Adrenal Hyperplasia (CAH)

Congenital adrenal hyperplasia (CAH) is a group of inherited genetic disorders that affect your adrenal glands. You have one adrenal gland sitting on top of each kidney. These glands make hormones that your body needs to work properly, including:

• Cortisol: Cortisol helps your body handle stress, illness or injury. It also helps manage your blood sugar, blood pressure and energy levels.
• Aldosterone: Aldosterone helps your body balance salt and water. This helps support your blood pressure and blood volume when you aren’t drinking or have low electrolyte levels.
• Androgens: Androgens are male sex hormones, like testosterone. They help start puberty and guide normal growth and development.

If you have CAH, your adrenal glands don’t have the enzyme they need to make these hormones correctly. Most often, it’s a missing or faulty 21-hydroxylase enzyme. Because of this, your adrenal glands may:

• Make too little cortisol
• Make too little aldosterone
• Make too much androgen

CAH is sometimes called adrenogenital syndrome because it affects both adrenal hormones and sexual development.

Types of congenital adrenal hyperplasia

There are two main types of CAH.

Classic congenital adrenal hyperplasia (CAH)

Classic CAH is the more severe form. It usually shows up at birth or shortly after. It can be life-threatening without treatment. There are two subtypes:

• Salt-wasting CAH: This is the most severe form. Your adrenal glands don’t make enough aldosterone and cortisol. Without enough aldosterone, your body can’t keep the right balance of salt and water. This can lead to a salt-wasting crisis. Without quick treatment, this may cause dehydration, low blood pressure and shock.
• Simple-virilizing CAH: This form is less severe than salt-wasting CAH. Your body still makes too little cortisol and too much androgen. But aldosterone levels are closer to normal. That means people with this form usually won’t have a life-threatening salt imbalance that puts them at risk for low blood pressure and shock. But higher androgen levels can affect growth and sexual development.

Nonclassic congenital adrenal hyperplasia (CAH)

Nonclassic CAH is the mildest and most common form overall. It usually doesn’t appear until later in childhood, the teen years or adulthood.

You may have minor symptoms or none at all. When symptoms do happen, they’re often related to extra androgens.

Congenital adrenal hyperplasia symptoms

Symptoms of congenital adrenal hyperplasia (CAH) can vary based on the type and how your body makes hormones. Symptoms develop because your body has too much androgen or too little cortisol or aldosterone.

Symptoms at birth or in early infancy (classic CAH)

Congenital adrenal hyperplasia in females can sometimes cause atypical genitalia at birth. Male babies may have an enlarged penis.

In severe (salt-wasting) CAH, babies of either sex can develop a condition called an adrenal crisis. This usually happens within the first one to two weeks of life and needs immediate treatment.

Symptoms during childhood (classic or nonclassic CAH)

As children grow, high androgen levels can cause:

• Early puberty
• Rapid growth at first, but shorter adult height
• Severe acne

Symptoms in females

Extra androgens in females can lead to:

• Excess facial or body hair
• Irregular or missing periods
• Deepening voice
• Increased muscle mass
• Enlarged clitoris
• Fertility issues

Symptoms in males

Symptoms in males may be less obvious, especially early on. They can include:

• Early puberty
• Noncancerous testicular growths
• Fertility issues

Symptoms of nonclassic CAH

Nonclassic CAH is milder. You may not have any symptoms. If you do, you might notice:

• Early puberty
• Acne
• Irregular periods
• Excess body or facial hair
• Male-pattern hair thinning
• Fertility issues

Congenital adrenal hyperplasia causes

CAH happens because of a problem with one of the enzymes your adrenal glands need to make hormones. Enzymes are like helpers that guide your body through each step of hormone production. If one is missing or not working right, your body can’t make hormones the way it should.

The most common cause of CAH is a shortage of an enzyme called 21-hydroxylase. Less often, CAH happens when you lack the 11-beta-hydroxylase enzyme.

Changes (variants) in a certain gene affect your levels of these enzymes.

Risk factors

Congenital adrenal hyperplasia (CAH) is a genetic condition that follows an autosomal recessive pattern. That means you must inherit the affected gene from each biological parent for you to have the condition. You’re more likely to have CAH if:

• Both of your parents carry the affected gene
• You have a biological family history of CAH
• You have a sibling with CAH

Complications of this condition

In classic CAH (especially the salt-wasting type), your body can lose too much salt and fluid. This can lead to a life-threatening adrenal crisis. Complications may include:

• Dangerous electrolyte imbalances
• Irregular heartbeat
• Cardiac arrest

How doctors diagnose CAH

Healthcare providers diagnose CAH at different times in life, depending on the type.

Before birth (prenatal testing)

If CAH runs in your family, your provider may offer testing during pregnancy. This can include:

• Chorionic villus sampling (CVS)
• Amniocentesis

These tests look for gene changes linked to CAH.

Newborn screening (classic CAH)

In the U.S., your baby’s provider will screen for CAH shortly after birth as part of routine newborn screening. This involves a heel-prick blood test that checks levels of a hormone called 17-hydroxyprogesterone (17-OHP). High levels can be a sign of classic CAH.

Testing after symptoms appear

If your provider doesn’t find CAH at birth or you have the nonclassic type, they may diagnose it later when symptoms show up.

Tests may include:

• Physical exam: To check for signs like early puberty or excess hair growth
• Blood tests: To measure hormone levels, including 17-OHP, cortisol and androgens
• Urine (pee) tests: To look at hormone byproducts
• ACTH stimulation test: To see how your adrenal glands respond to a hormone signal
• Genetic testing: To confirm the diagnosis or help with family planning

How is congenital adrenal hyperplasia (CAH) treated?

Congenital adrenal hyperplasia treatment focuses on replacing missing hormones and controlling excess androgen. Your healthcare provider will monitor your condition and order regular blood tests to check your hormone levels. Your care plan depends on the CAH type and your symptoms.

Treatment for classic CAH

Your healthcare provider may prescribe several medications to treat classic CAH.

Salt (sodium) supplements

A baby with classic CAH may need extra salt, especially in their first year of life. This is because their body doesn’t make enough aldosterone to hold on to sodium.

Your baby’s provider may recommend salt supplements. This is to help maintain normal fluid balance, blood pressure and growth until your baby is able to get enough salt from foods.

Hormone replacement therapy

Most people with CAH need medication to replace hormones their body can’t make. Medications may include:

• Glucocorticoids (like hydrocortisone): These replace cortisol and help lower excess androgen levels. You may need higher doses during illness, injury or stress (called stress dosing).
• Mineralocorticoids (like fludrocortisone): These replace aldosterone and help your body balance salt and fluids.

People with classic CAH usually need these treatments every day for life.

CRF-1 antagonist

Along with hormone therapy, your provider may recommend a CRF-1 antagonist. This medication helps control androgen levels, which allows for lower doses of glucocorticoids. This is important because high doses of steroids over time can cause side effects.

In 2024, the U.S. Food and Drug Administration approved the first CRF-1 antagonist. Crinecerfont (Crenessity™) is approved for people with classic CAH ages 4 and up. You take it with food that contains some fat.

You still need to take hormone therapy with this medication. It’s an add-on treatment, not a replacement.

Treatment for nonclassic CAH

If you have nonclassic CAH, you may not need treatment at all. If symptoms develop, treatment may include:

• Low-dose glucocorticoids
• Hormonal therapies, like birth control pills, to manage symptoms

Some people only need treatment for a short time. You usually won’t need lifelong treatment.

Is congenital adrenal hyperplasia curable?

Congenital adrenal hyperplasia (CAH) isn’t curable. It’s a lifelong condition that you’re born with.

But treatment can help you manage symptoms, balance your hormones and live a healthy life. Many people with CAH do well with the right care and regular follow-up.

What is the life expectancy of someone with congenital adrenal hyperplasia?

With early diagnosis and proper treatment, most people with CAH have a normal or near-normal life expectancy. With ongoing treatment, you can live a healthy, active life with CAH. Many people go to school, work and have families.

If you have classic CAH, you’ll need to take medication every day for life. If you stop treatment, your symptoms can come back and may become serious.

Outcomes can vary, but you may experience:

• Normal overall health with proper treatment
• Shorter adult height (in some cases)
• Fertility issues, depending on hormone control
• The need for lifelong monitoring and changes to your medications

Children who receive early treatment usually grow and develop more typically than people diagnosed later.