ABSTRACT
Nonclassical adrenal hyperplasia (NC-CAH) is caused by a deficiency in the activity of the 21-hydroxylase enzyme and is the most common autosomal recessive disorder. The clinical features of the disease sre highly variable, and therefore the diagnosis may be overseen. The disorder is characterized by hyperandrogenism of adrenal origin that may become evident during childhood, adolescence or adulthood. The symptoms vary from premature pubarche, mestrual disturbances, hirsutism and virilization to those cases without any clinical evidence of the disease, as described in the cryptic form. The diagnostic approach includes an initial measurement of plasmatic 17OH-progesterone (17OHP) and androgen levels, and an ACTH test in those with elevated baseline 17OHP. The definitive diagnosis of this entity is performed with the documentation of abnormalities in both alleles of the CYP21A2 gene. This paper reviews the clinical, molecular and treatment of patients with NC-CAH.