Cushing's disease Health Article

Definition

Cushing’s disease is a condition in which the pituitary gland releases too much adrenocorticotropic hormone (ATCH). The pituitary gland is an organ of the endocrine system.

Cushing's disease is a form of Cushing syndrome.

Alternative Names

Pituitary Cushing's disease

Causes, incidence, and risk factors

Cushing's disease is caused by a tumor or excess growth (hyperplasia) of the pituitary gland. This gland is located at the base of the brain.

People with Cushing's disease have too much ACTH. ACTH stimulates the production and release of cortisol, a stress hormone. Too much ACTH means too much cortisol.

Cortisol is normally released during stressful situations. It controls the body's use of carbohydrates, fats, and proteins and also helps reduce the immune system's response to swelling (inflammation).

Symptoms

• Abdomen that sticks out and thin arms and legs (central obesity)
• Acne or skin infections
• Collection of fat on the back of the neck (buffalo hump)
• Depression
• Diabetes
• Easy bruising
• Excessive facial hair growth in females
• Headache
• Impotence
• Increased urination
• Moon face (round, red, and full)
• Osteoporosis
• Purple stretch marks on the abdomen, thighs, and breasts
• Stopping of menstruation
• Weakness
• Weight gain

Signs and tests

Tests are done to confirm there is too much cortisol in the body, then to determine the cause.

These tests confirm too much cortisol:

• 24-hour urine cortisol
• Dexamethasone suppression test (low dose)

These tests determine cause:

• Brain MRI
• Dexamethasone suppression test (high dose)
• Serum ACTH levels
• Test of corticotropin-releasing hormone, which acts on the pituitary gland to cause the release of ACTH (CRH test)
• Test that measures ACTH levels in the veins that drain the pituitary gland (petrosal sinus sampling)