Substitution therapy in adult patients with congenital adrenal hyperplasia.

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive inherited disorders caused by defective steroidogenesis. Steroid 21-hydroxylase deficiency (21OHD) is its most prevalent form, accounting for over 90% of all cases. Clinically classic 21OHD is characterised by glucocorticoid deficiency and adrenal androgen excess with (salt wasting form) or without (simple virilising form) additional mineralocorticoid deficiency. Life-saving glucocorticoid substitution therapy has been available since the 1950s and enables long-term survival, and potentially, a good quality of life. However, care of adult patients with classic congenital adrenal hyperplasia is challenging for two main reasons: firstly, there is no glucocorticoid preparation available mimicking circadian cortisol release and adaptation to stress and secondly, management of adult patients is still in its infancy. There is no evidence-based treatment and experienced centres, taking care of larger patient cohorts, are only emerging. In this article we aim to guide physicians on the treatment and monitoring of adult patients with 21OHD, based on the clinical studies available and our own clinical experience.