[Comment] The road towards standardisation in cyclic Cushing's syndrome

Endogenous Cushing's syndrome is a severe, potentially lethal, endocrine condition. It is well known for its pleomorphic clinical manifestations that often overlap with those of frequent endocrine and non-endocrine disorders like arterial hypertension, type 2 diabetes, obesity, polycystic ovary syndrome, or postmenopausal osteoporosis.1 The absence of specific signs and symptoms leads to both over-testing and delayed diagnosis in patients with metabolic syndrome. Most clinical and biochemical manifestations are produced by excessive cortisol production from the adrenal glands, driven by autonomous adrenal tumours or by adrenocorticotropic hormone of pituitary or ectopic origin.