Recognising and diagnosing Cushing’s syndrome in primary care: challenging but not impossible

The catalyst for this article was the experience of one of the authors whose diagnosis of Cushing's was not immediately recognised despite the presence of numerous suggestive clinical features and comorbidities.This prompted the authors to convene a group of primary and secondary care clinicians to explore how to increase awareness and simplify the process of recognising and diagnosing Cushing's syndrome (CS) in primary care. WHY IS IT IMPORTANT NOT TO OVERLOOK CUSHING'S SYNDROME?Endogenous CS has traditionally been considered a rare condition, with an estimated annual incidence of 1.8 to 3.2 cases per million population, 1 although a recent study suggests the true incidence may be considerably higher, especially in individuals aged <65 years. 2 CS can be classified as either adrenocorticotrophic hormone (ACTH)-dependent or ACTH-independent.ACTH-dependent CS is caused by a pituitary adenoma (also known as Cushing's disease) or an ectopic ACTH-producing tumour.In the absence of exogenous corticosteroid therapy, ACTH-independent CS points to an adrenal origin.CS is an important diagnosis not to overlook because of its significant physical and psychological morbidities, associated comorbidities, and the excess mortality that complicates uncontrolled hypercortisolism (prior to effective treatments becoming available, 5-year mortality rate was 50% after symptom onset).