Diagnosis and management of classical congenital adrenal hyperplasia

•The most common cause of CAH is 21-hydroxylase deficiency.•CAH can cause glucocorticoid and mineralocorticoid deficiency with androgen excess.•CAH causes virilized external genitalia in female newborns.•Treatment of CAH includes optimal steroid supplementation.•Individuals with CAH require regular medical and psychosocial follow up. Congenital adrenal hyperplasia (CAH) is among the most common genetic disorders. Deficiency of adrenal steroid 21-hydroxylase deficiency due to mutations in the CYP21A2 gene accounts for about 95% cases of CAH. This disorder manifests with androgen excess with or without salt wasting. It also is a potentially life threatening disorder; neonatal screening with 17-hydroxyprogesterone measurement can diagnose the condition in asymptomatic children. Carefully monitored therapy with glucocorticoid and mineralocorticoid supplementation will ensure optimal growth and development for children with CAH. Genital surgery may be required for girls with CAH. Continued care is required for individuals with CAH as adults to prevent long-term adverse consequences of the disease, including infertility, metabolic syndrome and osteoporosis.