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Facts about CAH Congenital Adrenal Hyperplasia

This information was prepared by your An organ at the base of the brain, called health care team to help you learn about the pituitary gland, helps regulate the congenital adrenal hyperplasia (CAH). adrenal glands. CAH is a genetic disorder of the adrenal glands that affects the body's general health, growth, and development.

What are the adrenal glands? The adrenal glands are a pair of walnut-sized organs above the kidneys. They make hormones, which act like chemical messengers to affect other organs in the body. Each adrenal gland has two parts: the medulla (the inner part), and the cortex (the outer part).The medulla makes the hormone adrenaline. The cortex makes the hormones cortisol, aldosterone, and androgens. CAH affects how the adrenal cortex works. In severe cases, the adrenal medulla may also not function normally.

What do adrenal hormones do? Hormones made by the adrenal glands are important for the body's normal function. Cortisol affects energy levels, sugar levels, blood pressure, and the

Patient Information Publications 1 Facts about CAH: Congenital Adrenal Hyperplasia body's response to illness or injury. short stature. Girls exposed to high levels Aldosterone helps maintain the proper of androgens before birth may have salt level. Androgens are male-like abnormal external genitalia at birth. hormones needed for normal growth Although their internal female organs are and development in both boys and girls. normal, excess androgens may also Adrenalin affects blood sugar levels, affect puberty and cause irregular men- blood pressure, and the body's response strual periods. to physical stress. Too much cortisol replacement also caus- What is CAH? es abnormal development in children. Side effects include obesity and short The adrenal glands help keep the body stature. Also, too much hydrocortisone, in balance by making the right amounts the medicine given to replace cortisol in of cortisol, aldosterone, and androgens. the body, can cause decreased bone But in CAH, production of cortisol is density (osteoporosis) and high choles- blocked. Some children with CAH also terol levels. lack aldosterone. These imbalances cause the adrenal gland to make too Are there different types of much androgen. CAH? Symptoms There are many types of CAH. The Too little cortisol may cause tiredness severe form is called classic CAH, while and nausea. During illness or injury, low the mild form is called nonclassic CAH. cortisol levels can lead to low blood pres- sure and even death. Classic CAH The most common is 21-hydroxylase Lack of aldosterone, which occurs in deficiency (95 percent of cases). A child three out of four patients with classic with this type of CAH has adrenal glands CAH, upsets salt levels. This imbalance that cannot make enough cortisol and may cause dehydration (too little fluid may or may not make aldosterone. As a within the body), and possibly death. result, the glands over-work trying to Chronic salt imbalance may also cause make these hormones and end up mak- abnormal growth. ing too much of what they can make: Too much androgen causes abnormal androgens. physical development in children. Boys The second most common form of CAH and girls with CAH may grow too fast, is 11-hydroxylase deficiency. A child with develop early pubic hair and acne, and this type of CAH has adrenal glands that stop growing too soon, causing

Patient Information Publications 2 Facts about CAH: Congenital Adrenal Hyperplasia make too much androgen and not For a child to have CAH, each parent enough cortisol. Children with this type of must either have CAH or carry a genetic CAH may also have high blood pressure. mutation. This means that if two parents These patients do not have aldosterone are CAH carriers (that is, they have the deficiency. gene for CAH but not the disorder), their children have a 25 percent chance (1 in Rare other types of CAH include 3-beta- 4) of being born with CAH. Each sibling hydroxy-steroid dehydrogenase deficien- without CAH has two chances in three of cy, lipoid CAH, and 17-hydroxylase defi- being a carrier. Tests can be done to find ciency. out if someone is a carrier. Nonclassic (late-onset) CAH Classic CAH occurs in 1 in 15,000 This type of CAH is a mild form of CAH births. and is almost always due to 21-hydroxy- lase deficiency. Only a handful of people have been described as having nonclas- sic (mild) CAH due to other causes. People with nonclassic 21-hydroxylase deficiency make enough cortisol and aldosterone, but they make excess androgens. Symptoms come and go, beginning at any time but typically in late childhood or early adulthood. Boys often do not need treatment. Girls usually need treatment to suppress their excess androgens. How is CAH treated? Nonclassic CAH is common. One in The standard treatment for classic 21- every 1,000 people has nonclassic hydroxylase deficiency is hydrocortisone 21-hydroxylase deficiency. Incidence is which replaces cortisol, and fludrocorti- higher in certain ethnic groups including sone (Florinef) which replaces aldos- Ashkenazic Jews, Hispanics, Yugoslavs, terone. For 11-hydroxylase deficiency, and Italians. the treatment is only hydrocortisone. How is CAH inherited? Patients can be started on longer-acting An inherited disorder is one that can be forms of hydrocortisone (i.e. prednisone passed from the parents to their children. or dexamethasone) when they are done CAH is a type of inherited disorder called growing. “autosomal recessive.”

Patient Information Publications 3 Facts about CAH: Congenital Adrenal Hyperplasia Because replacement medications cannot How long can people live mimic the body's exact needs, patients, with CAH? on average, are about 4 inches shorter People with CAH have a normal life than their peers. expectancy. Patients with the nonclassic form of CAH, Can a woman with CAH need only hydrocortisone (or a longer-act- become pregnant and have ing form of hydrocortisone). Some a baby? patients with nonclassic CAH are able to Increased androgens may cause irregular come off medication as adults, but menstrual periods and make it harder for patients with classic CAH need lifelong a woman with CAH to conceive a child. treatment. But if she takes her medications as What if a child with CAH directed, she can become pregnant and has an illness, surgery, have a baby. or a major injury? Do men with CAH have During these times, a child with CAH fertility problems? needs closer medical attention and Men who take medications as directed should be under a doctor's care. More usually have normal fertility. Rarely, how- cortisol is needed to meet the body's ever, they may develop “adrenal rest tis- increased needs for this hormone. Higher sue” in their testicles. This is when adre- doses of hydrocortisone are given by nal tissue grows in other parts of the body mouth or sometimes by intramuscular such as the testicles or scrotum. Having injection. Intravenous medication is need- adrenal rest tissue may affect a man's ed before surgery. ability to father a child. The tissue does Medical Alert Identification not turn to cancer, but it can grow enough In an emergency, it is important to alert to cause discomfort or infertility. Large medical personnel about the diagnosis growths are rare, and surgery is usually of adrenal insufficiency, so wearing a not needed. medical alert identification bracelet or Do children with CAH necklace is recommended. The informa - outgrow it? tion on the medic alert should include, CAH cannot be outgrown. Classic CAH “adrenal insufficiency, requires Cortef.” It requires treatment for life. Some patients is also important for the adult or parent to with nonclassic CAH may not require learn how to administer an intramuscular treatment as adults. Treatment is tailored injection of Cortef in case of emergency. for each patient and adjusted during childhood for growth.

Patient Information Publications 4 Facts about CAH: Congenital Adrenal Hyperplasia