My doctor mentioned I might have Cushing's syndrome. What does that mean and how serious is it?

Cushing's syndrome occurs when the body is exposed to excessive levels of cortisol either produced internally or from long-term steroid medication. Symptoms can include weight gain particularly around the abdomen and face (often described as a 'moon face'), stretch marks, easy bruising, muscle weakness, high blood pressure, and mood changes. It is a serious condition if left untreated, as it significantly increases the risk of diabetes, osteoporosis, and cardiovascular disease. The cause matters enormously if medication-related, a careful dose reduction may resolve it. If due to a benign tumour of the pituitary or adrenal gland, surgery is often curative. Investigation involves specific blood, urine, and saliva tests, and appropriate imaging.