ultralow-dose dexamethasone to preserve endogenous cortisol stress response in nonclassical congenital adrenal hyperplasia: a new promising treatment

introduction nonclassical congenital adrenal hyperplasia (cah) is characterized by sufficient cortisol and aldosterone production at the cost of androgen overproduction. hydrocortisone or dexamethasone in supraphysiological doses are current treatment; however, their downside is suppression of endogenous cortisol production resulting in corticosteroid dependency. we aimed to treat children with nonclassical cah with a ultralow-dose dexamethasone to normalize androgen levels, without a detrimental effect on endogenous cortisol production. case presentation we recruited five patients diagnosed with nonclassical cah on the basis of clinical presentation, biochemical analyses, and genetic testing. anthropometric as well as biochemical parameters and bone age were measured on a regular basis. during treatment, an adrenocorticotropin (acth) stimulation test was performed. outcome measures were normalization of androgens and deceleration of the bone age advancement with sufficient endogenous cortisol response. androgen levels were normalized in all patients resulting in a deceleration of the bone age advancement. cortisol stress response remained normal in four out of five patients. only one patient needed hydrocortisone stress dosing. conclusions according to this case series, it seems that ultralow-dose dexamethasone in treatment of nonclassical cah would be a promising novel treatment strategy. the advantage of this treatment strategy is that adverse effects of hyperandrogenism can be reversed while preserving the endogenous cortisol stress response.