Congenital adrenal hyperplasia: diagnostic advances.

Congenital adrenal hyperplasia is a group of autosomal recessive disorders resulting from the deficiency of one of the five enzymes required for the synthesis of cortisol in the adrenal cortex. The most frequent is steroid 21-hydroxylase deficiency, accounting for more than 90% of cases. Much has been learned about the genetics of the various clinical forms of 21-hydroxylase deficiency, and correlations between the genotype and the phenotype have been studied extensively. Gene-specific diagnosis is now feasible and neonatal screening and prenatal treatment have been widely implemented. This discussion will be limited to the most common form of congenital adrenal hyperplasia, with focus on the diagnostic advances in this disease.