The classic and nonclassic concenital adrenal hyperplasias.

OBJECTIVE: The American Association of Clinical Endocrinologists Adrenal Scientific Committee has developed a series of articles to update members on the genetics of adrenal diseases.

METHODS: Case presentation, discussion of literature, table, and bullet point conclusions.

RESULTS: The congenital adrenal hyperplasia (CAH) syndromes are autosomal recessive defects in cortisol biosynthesis. The phenotype of each CAH patient depends on the defective enzyme and the severity of the defect. Clinical manifestations derive from both failure to synthesize hormones distal to the enzymatic block, as well as consequences from cortisol precursor accumulation proximal to the block, often with diversion to other biologically active steroids. The most common form of CAH is 21-hydroxylase deficiency, which occurs in the classic form in 1 in 16,000 newborns and in a milder or nonclassic form in at least 1 in 1,000 people.

CONCLUSION: This article reviews the various forms of CAH and pitfalls in the diagnosis and treatment of these conditions.