Cushing's disease is a disorder of the pituitary and adrenal glands in which too much of a hormone called cortisol is made. It is part of Cushing's syndrome, which is a complex of different diseases having to do with too much cortisol. Cortisol has several effects on the body. In excess, cortisol can cause different complications on different organs of the body.
Cortisol Production
Cortisol is a hormone secreted by the adrenal cortex in response to stimulation from ACTH, a hormone secreted by the pituitary gland. Cushing's disease results when the pituitary gland produces too much ACTH, thus triggering more cortisol production.
Cortisol Function
Cortisol has several functions in the human body, mostly to do with response to stress. Cortisol releases glucose (sugar) into the blood, helps store fat, increases the heart rate, and reduces inflammation. Too much cortisol results in Cushing's syndrome.
Effects on the Skin
With Cushing's disease, the skin becomes thin and easy to bruise. Fat also accumulates in excess in some parts of the body just below the skin. Striations, which are purple lines where the skin is thinned, form at the thighs, arms, abdomen, and breasts. Acne is also a common problem.
Effects on the Immune System
Cortisol reduces the function of the immune system. In fact, people whose immune system goes awry are usually prescribed cortisol to tone down the immune response. People with Cushing's disease are more prone to infection and poor wound healing.
Effects on the Circulatory System
Cortisol increases blood pressure and heart rate. This places additional strain on the heart and lungs, as the heart needs to work harder to get blood through the body. The increased pressure to the lungs causes an increase in fluid secretions in the lungs.
Treatment
Treatment of Cushing's disease depends what is causing the pituitary gland to produce excess ACTH or what is causing the adrenal glands to produce excess cortisol. This may be as simple as medication to counter the cortisol or surgery to remove tumors on the glands.
