Non-Classic Congenital Adrenal Hyperplasia in Childhood: A Review

Congenital adrenal hyperplasia (CAH) is a heterogeneous group of autosomal recessive disorders due to defects in adrenal steroid biosynthesis. In about 90% of patients, CAH is caused by pathogenetic variants in CYP21A2 gene, impairing the function of 21-hydroxylase (21-OH) enzyme. CAH can present as classical form (simple virilizing or salt wasting) or as non-classical form (NC-CAH). NC-CAH is due to pathogenetic variants in the CYP21A2 gene that result in 20-70% residual activity of 21-hydroxylase. Early diagnosis may be missed, mainly in childhood, jeopardizing long-term outcome. This paper will review some information on clinical findings, symptoms, diagnostic approaches, and treatments of NC-CAH in childhood, allowing better management and long-term outcome.