Cushing's disease is caused by an adenoma, which is a benign tumor, on the pituitary gland. An excessive secretion of adrenocorticotropic hormone (ACTH) is caused by the pituitary tumor. ACTH signals the adrenal gland to produce high amounts of the steroidal hormone, cortisol. Continuous exposure of the body to high levels of cortisol is called hypercortisolism. The symptoms of Cushing's disease are either the result of hypercortisolism or damage caused by direct pressure of the tumor.
Hypercortisolism Symptoms
Cortisol is normally released during stressful situations. It regulates blood pressure and the normal functioning of the cardiovascular system. Cortisol regulates the metabolism of proteins, carbohydrates and fats from dietary intake to usable energy.
A common symptom of hypercorticolism is the development of upper body obesity. Patients with Cushing's disease will have a round full face and fatty pads between the shoulders. Red flushing of the face is common. In contrast to the increase of upper body obesity, there is a thinning of fat in the arms and legs.
Hypercorticolism causes the skin to become thin and fragile. An affected individual bruises easily. Cuts, infections and insect bites heal more slowly. Purple pink stretch marks referred to as striae, appear on the abdomen, thighs, buttocks, arms and breasts.
Osteoporosis, the development or worsening of hypertension, and diabetes often occur. Patients with Cushing's disease experience severe fatigue and muscle weakness. Irritability, anxiety, depression and mood swings are commonly experienced symptoms.
Symptoms Caused by Pressure
Direct pressure from the pituitary tumor is responsible for certain symptoms associated with Cushing's disease. The adenoma can affect surrounding critical neurovascular structures. Visual field defects, specifically in peripheral vision, are the result of pressure on the cranial nerve II (optic nerve). Panhypopituitarism is the result of direct pressure of the tumor on the pituitary gland. Panhypopituitarism is a condition of inadequate or absence of production of the pituitary hormone, ACTH.
Age and Gender-Specific Symptoms
Children with Cushing's disease tend to be obese and have a slower growth rate than healthy children. Women can experience excessive hair growth on the face, neck, chest, abdomen and thighs. Menstrual periods become irregular or even cease. Men can experience a decrease in libido and fertility.
