What is Cushing Syndrome? Understanding Symptoms, Causes, and Treatments

Cushing syndrome is a condition that occurs when your body is exposed to high levels of the hormone cortisol for an extended period. This excess cortisol can originate from your body producing too much, or from the prolonged use of certain medications known as glucocorticoids, which mimic cortisol’s effects.

Too much cortisol can lead to several distinctive signs of Cushing syndrome, such as fat accumulation between the shoulders (often called a buffalo hump), a rounded, full face (moon face), and purplish stretch marks on the skin. Beyond these visible symptoms, Cushing syndrome can also contribute to serious health issues like high blood pressure, bone density loss, and even type 2 diabetes in some instances.

Fortunately, effective treatments are available to lower cortisol levels and alleviate the symptoms of Cushing syndrome. Early diagnosis and treatment are crucial for improving the chances of a full recovery and preventing long-term health complications.

Symptoms of Cushing Syndrome

The signs and symptoms of Cushing syndrome can differ significantly from person to person, depending on the degree of cortisol excess.

Common Symptoms

Weight gain, particularly in the abdomen and trunk: Characterized by disproportionate weight gain in the midsection, while arms and legs may remain relatively thin.
Facial fullness and rounding (Moon face): The face appears rounder and fuller due to fat deposits.
Fatty deposit between the shoulders (Buffalo hump): An accumulation of fat develops on the upper back and base of the neck.
Pink or purple stretch marks (striae): These are typically visible on the abdomen, hips, thighs, breasts, and underarms.
Skin thinning and easy bruising: The skin becomes fragile, thin, and susceptible to bruising even with minor injuries.
Slow wound healing: Cuts, scrapes, and insect bites may take longer than usual to heal.
Acne: Breakouts and acne can develop or worsen.

Symptoms in Women

Women with Cushing syndrome may also experience:

Hirsutism: Increased growth of coarse, dark hair on the face, chin, and body.
Menstrual irregularities: Periods may become irregular or cease altogether.

Symptoms in Men

Men with Cushing syndrome may experience:

Decreased libido: Reduced sexual desire.
Infertility: Difficulties conceiving.
Erectile dysfunction: Problems achieving or maintaining an erection.

Other Potential Symptoms

Persistent fatigue: Feeling unusually tired and lacking energy.
Muscle weakness: Difficulty with physical tasks due to muscle weakness.
Mood disturbances: Depression, anxiety, and increased irritability.
Emotional lability: Difficulty controlling emotions and increased emotional reactivity.
Cognitive difficulties: Trouble concentrating, memory problems, and confusion.
Insomnia: Difficulty falling asleep or staying asleep.
Hypertension: Elevated blood pressure.
Headaches: Frequent or severe headaches.
Increased susceptibility to infections: More prone to developing infections.
Skin hyperpigmentation: Darkening of the skin in certain areas.
Osteoporosis: Loss of bone density, increasing the risk of fractures.
Growth retardation in children: Slowed growth rate in children.

When to Seek Medical Advice

Consult your doctor if you experience symptoms suggestive of Cushing syndrome, especially if you are currently taking glucocorticoid medications for conditions like asthma, arthritis, or inflammatory bowel disease.

Causes of Cushing Syndrome

Cushing syndrome arises from an excess of cortisol in the body. Cortisol, a hormone produced by the adrenal glands, plays a vital role in numerous bodily functions, including:

Regulating blood pressure.
Reducing inflammation.
Supporting cardiovascular function.
Managing blood sugar levels.
Facilitating the body’s use of food for energy.

Exogenous Cushing Syndrome: Glucocorticoid Medications

One common cause of Cushing syndrome is the use of glucocorticoid medications. These drugs are frequently prescribed to treat inflammatory conditions such as rheumatoid arthritis, lupus, and asthma. They can also be used for back and joint pain, skin rashes, and to prevent organ rejection after transplantation.

Glucocorticoids can be administered orally, intravenously, topically, or inhaled. Regardless of the form, prolonged use of high doses can lead to Cushing syndrome. This form is known as exogenous Cushing syndrome, meaning it originates from outside the body.

Endogenous Cushing Syndrome: Body’s Overproduction of Cortisol

In other cases, Cushing syndrome develops when the body itself produces too much cortisol. This is termed endogenous Cushing syndrome. The production of cortisol is regulated by adrenocorticotropic hormone (ACTH), which is released by the pituitary gland. Tumors can sometimes disrupt this process, leading to excess cortisol. Issues within the adrenal glands themselves can also cause overproduction.

Endogenous Cushing syndrome can be caused by:

ACTH-producing pituitary adenomas (Cushing’s Disease): Pituitary adenomas are noncancerous tumors in the pituitary gland, located at the base of the brain. These tumors can secrete excessive ACTH, stimulating the adrenal glands to produce more cortisol. When Cushing syndrome is caused by a pituitary adenoma, it is specifically referred to as Cushing’s disease. This is more prevalent in women and represents the most common form of endogenous Cushing syndrome.
Ectopic ACTH-producing tumors: In rare instances, tumors located outside the pituitary gland, in organs that do not typically produce ACTH, can secrete ACTH. This “ectopic” ACTH production can also trigger excessive cortisol release. These tumors, which may or may not be cancerous, are most often found in the lungs, pancreas, thyroid, or thymus gland.
Adrenal gland tumors or hyperplasia: Problems within the adrenal glands themselves can lead to cortisol overproduction. Adrenal adenomas, benign tumors in the adrenal gland’s outer layer, are a common cause. While most are non-cancerous, some adrenal adenomas can produce excess cortisol. Adrenocortical carcinomas, cancerous tumors of the adrenal cortex, are rare but can also cause Cushing syndrome. Adrenal nodular hyperplasia, characterized by multiple cortisol-producing nodules in the adrenal glands, is another potential cause.
Familial Cushing syndrome: In rare cases, individuals may inherit a genetic predisposition to develop tumors in endocrine glands. If these tumors produce ACTH or cortisol, familial Cushing syndrome can result.

Complications of Untreated Cushing Syndrome

If left untreated, Cushing syndrome can lead to a range of serious complications, including:

Osteoporosis: Significant bone density loss, increasing the risk of fractures, particularly in the hips, spine, and ribs.
Hypertension: Chronically elevated blood pressure, increasing the risk of heart disease and stroke.
Type 2 diabetes: Impaired glucose metabolism leading to high blood sugar levels and increased risk of diabetes.
Increased susceptibility to severe infections: Weakened immune system making individuals more vulnerable to infections.
Muscle atrophy: Loss of muscle mass and strength, contributing to weakness and fatigue.

Early diagnosis and appropriate treatment are essential to manage Cushing syndrome effectively and minimize the risk of these serious complications.

By Mayo Clinic Staff

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