[Self-induced Cushing's syndrome due to dexamethasone abuse in nasal spray: clinical and biochemical study]

We studied a 55-year-old woman with remarkable cushingoid features, which presented biochemical evidence of suppression of the hypothalamus-hypophysis-adrenal axis. In the detailed anamnesis, we discovered that the patient had used during more than two years a nasal spray containing dexamethasone. In the initial assessment of the suprarenal function, in addition to suppressed concentrations of cortisol and ACTH, we observed the absence of response to acute stimulus (insulinic hypoglycemia and short ACTH test), as well as a normal response to sustained ACTH stimulus. After discontinuing the intranasal administration of dexamethasone, the patient remained asymptomatic; the basal concentrations of ACTH and cortisol, as well as the levels of urinary free cortisol, were normal at 3 months and the responses of cortisol and ACTH to their stimulus were restored to normal levels at 6 months. We conclude that in the cases of Cushing's syndrome with suppression of the hypothalamus-hypophysis-adrenal axis, it is necessary to conduct a detailed investigation on the consumption of glucocorticoids through unusual ways. The presence of a normal response to the sustained stimulus with ACTH may be a quick recovery index of the suprarenal function.