Congenital Adrenal Hyperplasia (CAH) in Adults
|What is CAH?|
|How does this affect me?|
|What types of CAH are there?|
|What symptoms does a person have who develops CAH as an adult?|
|How is adult onset CAH diagnosed in women?|
|How is it treated?|
|What should I do if I develop an illness such as flu?|
|How does the specialist monitor your CAH?|
|Is there a genetic test?|
|How common is CAH?|
|Will I pass the condition onto my family?|
|Can I get pregnant if I have CAH?|
|Can CAH be detected in the unborn baby and can this be treated before birth?|
|Can I expect to live as long as others?|
|Does hydrocortisone remove my excess hairs?|
|Is surgical correction ever required?|
|I am a man so what about me?|
|Where can I get more information?|
What is CAH?
This condition is caused by an inherited defect in one of the enzymes in the adrenal glands. The adrenal glands manufacture the hormone cortisol and aldosterone from a form of fat called cholesterol. The process of making cortisol or aldosterone from cholesterol requires five steps each controlled by at least one activating protein which is called an enzyme. CAH is caused by a fault in one of these enymes which literally runs slow. The effect is that the patient may not make enough cortisol or aldosterone or both.
How does this affect me?
What types of CAH are there?
Many cases of CAH are found at birth or in children and are treated early. There is another type where the enzyme fault is slight and only becomes apparent at puberty when it has to work harder and its inability to speed up becomes apparent. This is called non classical or cryptogenic CAH. Others call this adult onset CAH. This pamphlet only describes this type of CAH and also the treatment of adult patients with CAH. For a guide concerning babies and children please see the CAH Support Group website on www.cah.org.uk
What symptoms does a person have who develops CAH as an adult?
The adult onset form is far less severe than the childhood version and usually never produces salt wasting. Often cortisol production is only slightly sluggish and only causes bother during stress such as illness or injury. Patients however may feel tired and listless at all times. The real trouble arises from the over production of the androgen. In the male this is unlikely to be ever noticed but the women certainly notices a change. She becomes more male like;
How is adult onset CAH diagnosed in women?
The doctor will measure androgen in the blood and note that it is far higher than expected for a woman. Then the blood will be tested for the partly processed hormones. In practice the commonest fault in over 95% of patients occurs in an enzyme called 21 hydroxylase . The partly processed backlog hormone in this variety of CAH is called 17 hydroxyprogesterone and this is the hormone the doctor will measure. If it is high then the patient has CAH. Another hormone sometimes measured is ACTH which is overproduced by the head hormone gland the pituitary. To check for salt wasting the hormone renin may also be measured. Sometimes the condition requires another test called a synacthen test. In this ACTH is injected and the doctor measures the rise in 17 hydroxyprogesterone. This is often required in borderline cases where the faulty enzyme is only slightly affected and needs to be overworked to show that it is defective.
How is it treated?
If you remember the fault in CAH is an under production of cortisol. This is easily replaced by giving the medicine hydrocortisone. This is usually given two or three times per day and is tailored to each patients needs as shown by their blood chemistry. Sometimes other cortisol replacement medicines are used such as prednisolone or dexamethasone for these have a longer action and can be given once per day. However patients react differently to these medicines especially dexamethasone and put on weight and such patients may be better on hydrocortisone even if it has to be taken 2 or 3 times per day. Another point to make is that often the specialist after measuring your chemistry may recommend that you take more hydrocortisone in the evening than in the morning. This is often done to suppress androgen hormone production during the night which is the peak time for production in everyone. In a few patients salt wastage may require replacement with the hormone fludrocortisone but this is not usual for the adult onset type of CAH.
What should I do if I develop an illness such as flu?
During times of stress such as illness or injury then you should double your steroid intake until you are better. Any vomiting or diarrhoea then contact your doctor immediately and be seen that day. Otherwise come into A+E. Always carry a card or Medialert badge, pendant or bracelet in case of emergency for it is essential doctors know you are on steroid treatment and why.
How does the specialist monitor your CAH?
This is done in adults by measuring the hormone 17 hydroxy progesterone known as 17OHP. Often the androgens may also be measured.
Is there a genetic test?
CAH is an inherited disorder and is passed onto you by both of your parents in the genes. Each cell has a set of instructions called genes which are stored in the cell as threadlike structures called chromosomes. Everyone has 23 pairs of chromosomes, one set from their father, the other from their mother. Each chromosome has thousands of genes each controlling some process the body requires.In the commonest form of CAH, the enzyme 21 hydroxylase is faulty. This is due to a fault in one gene only in chromosome number 6. The patient has a faulty gene on each of their two chromosome number 6 inherited from their mother and father. The reason why your mother or father do not seem to have your condition is that each has only one faulty gene whereas their second gene is healthy and compensates for the others fault. However you have have inherited the faulty gene from both your mother and father and that is why you have the condition. Your brother or sister might also have inherited the condition but may have not. They then may have inherited two healthy genes or be carriers having inherited one faulty gene from one or other parent and one healthy gene from the other. Your parents were carriers and had a 1 in 4 chance of passing the clinical condition to a child. In other words out of 4 children born to your parents the chance is that one will have clinical CAH, two will be carriers and one will not. Genetic studies on you and your family will identify the gene and will allow the doctor to say who in your family are carriers.
How common is CAH?
In Europe CAH occurs in 1 in 5000 people. The carrier state is found far more frequently in 1 in 37 people. So the chances of both parents being carriers is not high unless they are closely related.
Will I pass the condition onto my family?
To answer this question the gene will be measured in your partner. If your partner is a carrier then there is a 1 in 4 chance of one child being affected with clinical CAH and two being carriers. If your partner does has healthy genes then none of your children will develop the condition but some may be carriers. Genetic studies on your children will detect the carriers.
Can I get pregnant if I have CAH?
Yes, once you are under treatment.
Can CAH be detected in the unborn baby and can this be treated before birth?
Yes. During the pregnancy the patient with CAH continues taking the hydrocortisone as before. This hormone passes across to the unborn baby and automatically corrects any fault if baby has inherited CAH. During the pregnancy the dose of hydrocortisone will be monitored by measuring another hormone called androstenedione as 17 hydroxy progesterone is always elevated in pregnant women and cannot be used to monitor CAH.
However if you are the parent of a child with CAH you no doubt want to be sure that if the unborn baby has inherited CAH then it is treated before birth. This is done by testing the unborn baby for CAH by taking a sample of tissue from the neck of the womb (chorionic villous sampling) or amniotic fluid early on in the pregnancy. This is then genetically tested to see if the unborn baby has CAH and also to determine its sex. Of course the doctors do not know the answer till nearly 14 weeks of the pregnancy so it is likely that they will ask you to take dexamethasone until the answer is known. If the unborn baby does not have CAH or is a carrier but is unaffected then the dexamethasone will be stopped and all will be well. However if the unborn baby has CAH and is a girl then the dexamethasone will be continued till baby is born. This is essential in unborn girls to prevent a build up of androgen turning their genitalia into that resembling boys. If the unborn baby is a boy then the specialist may advise stopping the mothers dexamethasone as excessive male production in the unborn boy causes no problem. Of course affected babies will need treatment after birth.
Can I expect to live as long as others?
CAH does not reduce your life expectancy and you can expect to live a normal life
Does hydrocortisone remove my excess hairs?
In most patients it will but some require to take the medicine Dianette either alone or with cyproterone acetate for up to a year to remove unwanted and persistent hairs. Some hairs on the legs and arms are natural and cannot be removed by this method. These require removal by dilapatory creams or shaving as most women require to do who do not have CAH.
Is surgical correction ever required?
This pamphlet maily concerns treatment in adults most having developed the condition in adulthood.Some may have developed CAH in puberty or earlier and have been diagnosed later. Such patients may have genitalia requiring some plastic surgery mainly to shorten the clitoris or even open the vagina. This will be done by expert surgeons as quickly as possible.
I am a man so what about me?
If you are diagnosed as having CAH this is usually when you were a child. Normally your hydrocortisone will be continued as will the fludrocortisone if you require this. You will not require surgical correction. In mild conditions of CAH developed in adulthood then no treatment may be required. Your specialist will advise. Nevertheless genetic testing of yourself, your spouse/partner and children is essential.
Where can I get more information?
Why not contact the CAH Support Group at
CLIMB, CLIMB Building, 176 Nantwich Road, Crewe, Cheshire, UK
Telephone: Freephone 0800 652 3181
or the Adrenal Hyperplasia Network at www.ahn.org.uk
Ó NHS Tayside; 2006; version 1.0
Disclaimer; no liability whatsoever is accepted for information given and all such information, especially with regard to drug usage (UK version provided), must be checked with a persons health provider.