What is CAH?
There’s lots to learn about Congenital Adrenal Hyperplasia (CAH), but there’s a lot of information out there too. On this page, you’ll find pictures, videos, articles and links to other resources to help you find out a little more about CAH.
CAH - a simple description
CAH (congenital adrenal hyperplasia) occurs approximately once in every 15,000 people worldwide. It is an inherited condition which prevents the adrenal glands functioning correctly. To stay healthy, people with CAH must take daily life-long medication to replace the hormones which their adrenal glands don’t make. People with CAH are at risk of a life-threatening adrenal crisis in an emergency, for instance if they are ill or injured.
The three mains steroids (or hormones) involved in CAH are Corticosteroids, Mineralocorticoids and Androgens.
Although there are many different grades of severity of CAH (congenital adrenal hyperplasia), there are three main types of CAH (over 90% of cases) which are caused by a deficiency of an enzyme called 21 hydroxylase. The three main types of CAH are ‘Salt-wasting’ (most cases), ‘Non-salt wasting’ and ‘late onset CAH’.
Another type of CAH is caused by a deficiency of the enzyme 11-beta hydroxylase and while deficiencies of other enzymes occur they are exceedingly rare.
Over 90% of people with CAH have a deficiency of an enzyme called 21 hydroxylase.
The most common types of CAH – 21 hydroxylase deficiency
The three main types of CAH caused by a deficiency of the 21 hydroxylase enzyme are salt-wasting, non-salt wasting and late onset. In these forms of CAH the production of Cortisol and Aldosterone is low.
In salt-wasting CAH, the hormone aldosterone in completely lacking which results in uncontrolled loss of salt from the body through urine.
In non-salt wasting CAH, the salt balance is usually normal. However, in stressful situations, those with non-salt wasting CAH may begin to lose salt and hence require extra treatment.
In both ‘salt wasting’ and ‘non-salt wasting’ types of CAH, the salt loss can cause acute dehydration, very low blood pressure (hypotension) and vomiting. As salt (sodium and chloride) and sugar (glucose) levels fall in the blood, potassium levels rise and if left untreated, a potentially life-threatening Adrenal Crisis can result.
Untreated CAH, or illness in a person with CAH, can cause a potentially life-threatening Adrenal Crisis.
‘Salt wasting’ and ‘non-salt wasting’ CAH can cause differences in early sexual development due to the body producing excess testosterone to compensate for the low levels of cortisol and aldosterone. In boys, this excess of testosterone causes early sexual development. In females, the excess in testosterone can cause differences in sexual development before birth.
Only by correcting the levels of Cortisol with substitute therapy does the body recognise normal levels and stop producing excessive amounts of testosterone.
CAH can cause differences in sexual development due to the body producing excess testosterone to compensate for the low levels of cortisol and aldosterone.
The mildest form of CAH – Late onset CAH
Last onset CAH can affect men and women at any age. As with other forms of CAH, the body tries to correct the low levels of aldosterone and cortisol by producing excess testosterone.
For women, symptoms of unwanted hair growth or irregular periods can start at any time after puberty. Often treatment with steroids is not necessary in women with late onset CAH. Instead, giving oestrogen as in the oral contraceptive can regulate testosterone from the ovary. In fact, the treatment of late onset CAH is usually the same as for the polycystic ovary syndrome because the two conditions are so similar.
For men, late onset CAH usually goes unrecognised although it may cause the sperm count to be low.
11-beta hydroxylase deficiency and other enzyme deficiencies
These types of CAH are much rarer that 21 hydroxylase deficiency. Treatment of these types of CAH is more complicated because high blood pressure can be severe if treatment inadequate. The balance of treatment in 11-beta hydroxylase deficiency is very difficult and an experienced specialist is essential.
A 5-minute infographic/sketch style video that explains key aspects of CAH.
A 5 minute video which explains key things about CAH using a sketch format – this video is also featured above and on our homepage.
A 10-minute cartoon-syle video that explains the key points of CAH – very informative for all!
BSPED aims to improve the care of children and young people with endocrine disorders and diabetes mellitus by bringing together professionals from a range of disciplines. Visit the ‘Clinical Resources’ section to find Patient Information about CAH.
Some useful resources from the CARES Foundation in the USA as well as other sources worldwide. Includes links to information about CAH in languages other than English.
Explain was developed as part of a project to improve communication between young people, their parents/carers and healthcare professionals in endocrine clinics. Explain was designed to help young people affected by various endocrine conditions talk with doctors and nurses, while also providing them with accessible information about those conditions.
Adrenas’ goal is to provide a safe and effective gene therapy treatment for adults and children living with classic CAH through the ADvance-CAH gene therapy program.
Lab Tests Online UK has been designed to help patients better understand the many clinical laboratory tests that are part of routine care as well as diagnosis and treatment of a broad range of conditions and diseases. The site is the product of a collaboration of professional societies representing the laboratory community.
Including a description of Adrenal Insufficiency, treatment aims, management of the condition and other information about related medication.
The Society for Endocrinology is the UK home of endocrinology. They bring together the global endocrine community to share ideas and advance the discipline of endocrinology.
A web-based project by the Society for Endocrinology that aims to give patients and the general public access to reliable online information on endocrine science.