Cushing's Syndrome (sometimes called hypercortisolism) is a hormonal disease caused by an abnormally high level of the hormone cortisol in the body. This may arise because of an endogenous or exogenous source of cortisol. Endogenous causes include the elevated production of cortisol by the adrenal glands, while exogenous causes include the excessive use of cortisol or other similar steroid (glucocorticoid) hormones over a prolonged period of time.
The adrenal glands are situated just above each kidney, and form part of the endocrine system. They have numerous functions such as the production of hormones called catecholamines, which includes epinephrine and norepinephrine. Interestingly, the outer layer (cortex) of the adrenal glands has the distinct responsibility of producing cortisol. This hormone is best known for its crucial role in the bodily response to stress.
At physiologically appropriate levels, cortisol is vital in maintaining normal sleep-wake cycles, and acts to increase blood sugar levels. It suppresses the immune system, regulates the effect of insulin on the metabolism of fats, proteins, and carbohydrates, and help with the homeostasis of water in the body.
Exogenous corticosteroids can also lead to Cushing's syndrome, when they are used as a form of long-term treatment for various medical conditions. In fact, the long-term use of steroid medication is the most common reason for the development of Cushing's syndrome.
Prednisolone is the most commonly prescribed steroid medicine. It belongs to a class of medicine that is sometimes used to treat conditions such as certain forms of arthritis and cancer. Other uses include the rapid and effective reduction of inflammation in conditions such as asthma and multiple sclerosis (MS), as well as the treatment of autoimmune conditions such as lupus erythematosus, and rheumatoid arthritis.
Overall, Cushing's syndrome is quite uncommon and affects approximately 1 in 50,000 people. Most of them are adults between the ages of 20 and 50. Women are 3 times more commonly affected than men. Additionally, patients who are obese, or those who have type 2 diabetes with poorly controlled blood sugar and blood pressure show a greater predisposition to the disorder.
Symptoms of Cushing's syndrome
There are numerous symptoms associated with Cushing's syndrome, which range from muscle weakness, hypertension, curvature of the spine (kyphosis), osteoporosis, and depression, to fatigue Specific symptoms which pertain to the skin are as follows:
- Thinning of the skin and other mucous membranes: the skin becomes dry and bruises easily. Cortisol causes the breakdown of some dermal proteins along with the weakening of small blood vessels. In fact, the skin may become so weak as to develop a shiny, paper-thin quality which allows it to be torn easily.
- Increased susceptibility of skin to infections
- Poor wound healing of bruises, cuts, and scratches
- Spots appear on the upper body, that is, on the face, chest or shoulders
- Darkened skin which is seen on the neck
- Wide, red-purple streaks (at least half an inch wide) called striae which are most common on the sides of the torso, the lower abdomen, thighs, buttocks, arms, and breasts, or in areas of weight gain. The accumulation of fat caused by Cushing's syndrome stretches the skin which is already thin and weakened due to cortisol action, causing it to hemorrhage and stretch permanently, healing by fibrosis.
- Acne: this can develop in patients of all ages.
- Swollen ankles: this is caused by the accumulation of fluid, called edema.
- Hyperhidrosis (excessive sweating)
Reviewed by Dr Liji Thomas, MD