Congenital adrenal hyperplasia: clinical symptoms and diagnostic methods

The aim of this paper is a straightforward presentation of the steroidogenesis process and the most common type of congenital adrenal hyperplasia (CAH) - 21-hydroxylase deficiency - as well as the analytical diagnostic methods that are used to recognize this disease. CAH is a family of common autosomal recessive disorders characterized by impaired adrenal cortisol biosynthesis with associated androgen excess due to a deficiency of one or more enzymes in the steroidogenesis process within the adrenal cortex. The most common and prototypical example of the CAH disorders group (90-95%) is caused by 21-hydroxylase deficiency. Less frequent types of CAH are 11β-hydroxylase deficiency (up to 8% of cases), 17α-hydroxylase deficiency, 3β-hydroxysteroid dehydrogenase deficiency, P450 oxidoreductase deficiency and StAR deficiencies. In the 21-hydroxylase and 11β-hydroxylase deficiency, only adrenal steroidogenesis is affected, whereas a defect in 3β-hydroxysteroid dehydrogenase or 17α-hydroxylase also involves gonadal steroid biosynthesis. Many countries have introduced newborn screening programs based on immunoassays measuring 17-hydroxyprogesterone from blood spots used for other neonatal screening tests which enable faster diagnosis and treatment of CAH. Currently, chromatographic techniques coupled with mass spectrometry are gaining popularity due to an increase in the reliability of the test results.