Cushing's syndrome is a rare disease caused by an excess of the hormone cortisol in the body. Cortisol is a hormone normally secreted by the adrenal glands and is necessary for life. It allows responding to stressful situations, such as illness, and affects most body tissues. When the body produces too much cortisol, Cushing syndrome develops, regardless of the cause. Some patients have Cushing's syndrome because they have a tumor in the adrenal glands, which causes them to make too much cortisol. Other patients have Cushing syndrome because they make too much of the hormone ACTH, which stimulates the adrenals to make cortisol. When ACTH comes from the pituitary, we speak of Cushing's disease. In Cushing's syndrome, the elevated level of cortisol produced by the adrenal glands increases the blood sugar level. The most common symptoms in adults are weight gain (especially in the trunk, and often not accompanied by weight gain in the arms and legs), high blood pressure (hypertension), and changes in memory, mood and concentration. Other problems such as muscle weakness appear due to the loss of protein in the body tissues.
