Severe Hyperandrogenism in 46,XX Congenital Adrenal Hyperplasia: Molecular Physiopathology, Late Diagnoses, and...

Congenital Adrenal Hyperplasia (CAH) is a group of autosomal recessive endocrine disorders characterized by alteration in adrenal hormonal secretions. The most common form is caused by CYP21A2 mutations that result in 21-hydroxylase deficiency. Clinical features can vary, from salt-wasting forms, characterized by a lack of mineralocorticoid activity with a risk of perinatal-onset adrenal crises, to "simple-virilizing" forms with sufficient aldosterone secretion, up to milder "non-classical" forms, with a variable grade of hyperandrogenism but no severe hormonal deficiencies. During pregnancy, CAH 46,XX fetuses are exposed to elevated androgen levels, leading to a variable grade of virilization and potential central nervous system effects if untreated. These patients are usually (but not always) assigned female at birth, but some cases may be misdiagnosed and assigned male, potentially inducing fertility, gender identity, and sexual behavior issues in adulthood. In these patients, the benefits and risks of a late gender transition should be carefully evaluated. In this paper, we reviewed the literature concerning the most interesting peculiarities of these conditions.