Therapy of classic congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency in childhood and youth

In infancy and childhood there are several pitfalls in the conventional treatment of classic congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. Newborns and infants require relatively low doses of hydrocortisone and may be at risk for hypoglycemia. Simultaneously there is a state of relative mineralocorticoid resistance, so that infants require relatively high doses of fludrocortisone in comparison to adults. In childhood, glucocorticoid overtreatment leads to growth inhibition and glucocorticoid undertreatment to acceleration of growth. Therefore, linear growth with age-appropriate growth velocity is the best clinical parameter for monitoring metabolic control in CAH. The need for salt supplementation during the first months of life is still under debate. Puberty is another critical phase of CAH treatment because of the changing endocrine milieu with increased cortisol clearance and an increase of insulin resistance, both resulting in a challenge to achieve good metabolic control of CAH. This review also focuses on glucocorticoid stress dosing and emergency education in patients with CAH.