Endocrine Abstracts

Classical congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency leads to glucocorticoid and mineralocorticoid deficiency. Management should be viewed as a process of care which requires input from an Inter-disciplinary Team. Glucocorticoid therapy should take the form of hydrocortisone in a starting dose of 10–12 mg/m² per day (divided into three or four doses) and the dose should be titrated to blood or urine profiles of cortisol and 17 hydroxyprogesterone. Mineralocorticoid replacement (9α fludrocortisone) requires higher doses in infancy and childhood compared to adolescence. Starting dose should be 150 μg/m² per day and thereafter titrated to plasma renin activity and blood pressure. Despite adequate glucocorticoid substitution and concordance with medical therapy, control can be difficult during puberty due to alterations in the clearance of hydrocortisone and dosing schedules may need to be adjusted to account for this. GH and IGF1 along with changes in sex steroid concentration influence the conversion of cortisol to cortisone through 11β hydroxysteroid dehydrogenase type 2. Twenty-four hours plasma cortisol and 17 hydroxyprogesterone profiling is a useful method for determining dose and frequency of hydrocortisone administration to avoid over and under treatment. Follow-up should address the many facets of CAH which should be assessed at an annual review and a suggested protocol is presented. A case for an extension of adolescent follow-up to cover the age range 19–25 years will be made.