Congenital adrenal hyperplasia refers to a collection of genetic disorders that affect the adrenal glands and their functions in the body. Adrenal glands are organs found at the top of kidneys and are responsible for the production of certain hormones, precisely mineralocorticoids, corticosteroids, and androgens. Mineralocorticoids handle the regulation of water and salt in the body, corticosteroids monitor how the body reacts to illness, and androgens are the sex hormones found in males. When the adrenal glands are not able to produce these hormones effectively, the body may fail to develop properly and may interfere with the development of the sex organs. Also, the body produces other hormones to supplement the missing ones.
The most frequent cause of CAH is the deficiency of the 21 - hydroxylase, which is the enzyme that aids in the production of aldosterone and cortisol. This deficiency can be a result of a gene mutation of CYP21A, and its degree of shortage will determine the severity of the condition. The 21- hydroxylase deficiency accounts for a majority of the case of CAH; over 90%. There are two categories of CAH, which are classical and non-classical. With classical, CAH the condition can be in the simple virilizing form or the salt-losing form. Of the two primary forms, classical CAH is the most dangerous, and often requires immediate treatment. CAH is also present in other forms, which are rare such as 17a-hydroxylase deficiency, congenital lipoid adrenal hyperplasia and 11-Beta-hydroxysteroid dehydrogenase deficiency.
The symptoms of CAH vary depending on the form of the condition and the gender of the patient. In males, a patient that is 21-hydroxylase deficient has normal genital growth. One of the symptoms of classical CAH is salt-wasting. The condition refers to the inability of an individual to retain water and salt. As the body loses these two compounds, it becomes dehydrated. The condition can also lead to abnormally low pressure, even shock and hypovolemia, which is a low flow of blood volume. A severe case of CAH can result in an adrenal crisis, which results in a circulatory collapse. Vomiting, weakness, and diarrhea are other signs of severe CAH. An infant may also suffer weight loss or poor weight gain.
In cases of mild 21-hydroxylase deficiency, males present phallic enlargement and early growth of pubic hair. The condition also causes males to grow faster in terms of height but then stop at below average standards. There is also advanced skeletal maturation. Salt- wasting is also a symptom in males with severe CAH. In rare forms of CAH such as 17-hydroxylase deficiency, male patients have irregular genitalia. In severe cases, males may have female genitalia and may even grow up as female but can suffer from a lack of breast development and hypertension. Males with 11-hydroxylase deficiency may experience salt-wasting at three weeks old and can develop hypertension.
Severe cases of classic CAH in females can manifest as ambiguous sex organs at infancy. Some of the abnormalities include clitoromegaly and complete or partial fusion of the labioscrotal folds. Even with external genitalia, though a female still has normal internal reproductive organs. In mild cases, the symptoms are the same as those in males with accelerated linear and skeletal growth. Adolescent females with mild CAH will experience abnormal facial and body hair growth, and irregular menses. In non-classical CAH, a female may be infertile. In 17- hydroxylase deficiency, an infant can have abnormal female traits but fail to menstruate or develop breasts in adolescence. A female with congenital lipoid hyperplasia can end up infertile or dead due to adrenal crisis.
The USA is among the developed countries that provide screening of newborns for congenital adrenal hyperplasia. Mild cases of CAH are not detectable during screening, but the symptoms start to present themselves during puberty. Such an individual can live a normal life without treatment. A doctor can determine if there is a need to treat the condition. Some tests check the genetic mutation associated with CAH. In most situations, these tests are administered during pregnancy. An expectant woman at high risk of birthing a baby with CAH needs to undergo accurate tests. Some imagining exams such as pelvic ultrasonography and CT scans can help identify CAH in adolescents. An infant with abnormal genitals requires close supervision to check for salt-wasting and other symptoms that may narrow down the diagnosis.