Cushing's Syndrome: Symptoms, Causes, Tests & Treatment

Cushing's syndrome develops when the body faces too much cortisol over time ^1,4. It can also result from medicines that act like cortisol ⁴.

Cortisol helps control blood pressure, blood sugar, swelling, and energy use ⁴. Yet too much cortisol can harm many parts of the body ¹.

This guide explains common signs, causes, tests, and treatment choices. It also covers safe steroid use, recovery, and long-term care.

Cushing's syndrome is also called hypercortisolism, which means having too much cortisol ⁸. The excess may come from medicine or from within the body ⁸.

Exogenous Cushing's syndrome comes from cortisol-like medicines ⁴. Endogenous Cushing's syndrome means the body makes too much cortisol ⁴.

The adrenal glands make cortisol and sit near the kidneys ¹⁰. Cortisol helps the body handle stress and perform several basic tasks ⁴.

Too much cortisol can harm heart, metabolic, immune, and mental health ¹. It can also affect skin, muscles, bones, and blood vessels ⁸.

Signs differ between people and can change with the amount of extra cortisol. The illness often gets worse slowly and may be hard to spot ⁹.

Fatigue and weight gain can have many other causes ⁴. This overlap can make testing and diagnosis complex ^6,9.

Cushing's syndrome covers harmful cortisol excess from any cause ². Cushing disease is one type of the wider syndrome ³.

Cushing disease starts with an ACTH-producing tumor in the pituitary gland ³. ACTH is a hormone that tells the adrenal glands to make cortisol ³.

The pituitary is a small gland at the base of the brain ⁴. Its tumors are called pituitary adenomas and are often not cancerous ⁴.

An ACTH-producing pituitary adenoma is the most common internal cause ². It is not the cause of every case.

Long-term glucocorticoid use is the most common cause overall ^2,4. Glucocorticoids are steroid medicines that work much like cortisol.

These medicines treat asthma, arthritis, lupus, and other health problems ^4,7. They also help prevent rejection after an organ transplant ⁴.

Risk also rises with certain pituitary, adrenal, or ACTH-producing tumors ². Endogenous disease often affects adults, but children can develop it ⁴.

Anyone using steroids for a long time should know the possible signs. However, never change a prescribed steroid without medical help.

Cushing's syndrome symptoms vary from one person to another ^4,7. Some signs give stronger clues than tiredness or weight gain alone ².

Several signs may build over time ⁹. A single symptom does not prove that cortisol is too high.

Changes in body shape and skin may include these signs:

Muscle weakness can affect areas near the hips and shoulders ². Weak muscles may also reduce the ability to exercise ³.

Bone pain or back pain may occur in some people ³. Weak bones can lead to rib or spine fractures ³.

High cortisol can affect hormones, blood sugar, mood, and sexual health ⁸. Possible features include the following changes:

These signs also occur with many other health problems. Metabolic syndrome can also cause central weight gain, high blood pressure, and insulin resistance ².

Children can show a distinct pattern. If a child gains weight while growing slowly, Cushing's syndrome may be a concern ⁴.

Untreated cortisol excess can lead to severe health problems ^1,4. Possible complications include the following conditions:

Cushing's syndrome can lower quality of life and increase death risk ¹. Infection, blood clots, heart attack, and stroke contribute to that risk ¹.

Causes fall into two main groups. One group involves steroid medicines, while the other starts inside the body ⁴.

Long-term, high-dose glucocorticoid use is the most common cause ⁴. These drugs act like cortisol and reduce swelling caused by illness.

Steroid exposure may come from several forms of treatment:

A medication review should include pills, shots, creams, and inhalers. Tell your clinician about every steroid product you use.

Do not stop glucocorticoids or lower the dose on your own. A sudden change can leave the body with too little cortisol.

A pituitary adenoma can make too much ACTH ³. The extra ACTH pushes the adrenal glands to make excess cortisol ³.

This form of the syndrome is called Cushing disease ³. It is the most common endogenous form ².

An ectopic tumor makes ACTH outside the pituitary gland ⁴. Ectopic means that the hormone comes from an unusual site.

These tumors may develop in the lungs, pancreas, thyroid, or thymus ⁴. Some are cancerous, while others are not.

Adrenal tumors can make cortisol without high ACTH levels ². Most adrenal tumors linked with this condition are not cancerous ⁴.

Adrenal cancer is a rare possible cause. Adrenal nodular hyperplasia can also lead to excess cortisol.

ACTH-dependent disease involves excess ACTH from a tumor ⁹. The tumor may be in the pituitary gland or elsewhere ⁹.

The extra ACTH then drives the adrenal glands to produce cortisol ¹. Cushing disease and ectopic ACTH syndrome belong to this group ¹.

ACTH-independent disease starts in the adrenal glands ⁹. An adrenal tumor or adrenal overgrowth makes cortisol on its own ^1,7.

Doctors use this difference when choosing later tests. They confirm internal cortisol excess before searching for its source ^2,3.

Cushing's syndrome can be difficult to diagnose. Its symptoms overlap with several common health problems ^4,6.

An endocrinologist is a doctor who treats hormone disorders. This specialist often directs the testing process.

The clinician reviews symptoms, health history, and all medicines ^4,6. Steroid exposure is a common cause to consider when evaluating Cushing syndrome ².

The review should include pills, shots, inhalers, and creams. Steroid treatment may explain the signs without more cortisol testing.

During the examination, the clinician may check for these changes:

No physical sign can confirm the condition by itself. Lab tests check whether the body is making too much cortisol ².

Recommended first tests include three main options ^1,2. A clinician may choose one or more based on your needs.

The testing options include the following methods:

Cortisol levels normally fall after sleep begins ⁴. In Cushing's syndrome, that late-night drop may not happen ⁴.

Saliva is collected at home and sent or returned to a lab ⁴. The test checks whether late-night cortisol remains high ⁴.

The urine test requires collecting all urine over 24 hours ⁴. The laboratory then measures the amount of free cortisol ⁴.

For the overnight test, dexamethasone is taken at night ⁴. Dexamethasone is a glucocorticoid used to test the body's cortisol control.

A blood sample is taken the next morning ⁴. Cortisol should drop after dexamethasone in people without the syndrome ¹⁰.

High cortisol after the dose can support more evaluation ¹⁰. It does not identify where the excess cortisol comes from.

No screening test is perfect ⁴. Doctors often use two tests to confirm the diagnosis ⁴.

More than one screening test may be needed for Cushing disease ³. A random blood cortisol test alone is not a suitable screening test ².

Depression, eating disorders, and alcohol use can resemble this syndrome. Other illnesses may also cause similar signs.

Mild Cushing's syndrome can look like metabolic syndrome ². Metabolic syndrome can include central obesity, insulin resistance, and high blood pressure ².

Testing can be long and complex. Results must be viewed with symptoms, medicine use, and the physical examination.

Doctors measure blood ACTH after confirming endogenous hypercortisolism ². This test helps identify the likely source of excess cortisol ².

A low or suppressed ACTH level suggests an adrenal cause ^2,8. Testing then focuses on the adrenal glands ².

A normal or high ACTH level suggests a pituitary or ectopic source ^2,8. More tests may help identify a pituitary or ectopic cause ².

A pituitary MRI can look for a pituitary tumor ². MRI uses detailed images to show the gland and nearby tissue.

A CT scan can examine the adrenal glands, chest, abdomen, or pelvis ². These scans may help find adrenal or ectopic tumors ².

Hormone testing comes before efforts to locate the source ³. Imaging results are then considered with the hormone pattern.

Inferior petrosal sinus sampling may help when the ACTH source remains unclear. This procedure takes blood near veins that drain the pituitary.

The care team compares that ACTH level with blood from another vein. Higher ACTH near the pituitary supports a pituitary source.

Similar levels in both areas suggest a source outside the pituitary. A specialist decides when this invasive test is needed.

Cushing's syndrome treatment aims to lower excess cortisol. The best plan depends on the cause ^5,6.

Treatment may involve a steroid taper, surgery, medicine, or radiation. Some people need more than one type of care.

If steroid medicine caused the condition, a clinician may lower the dose. The dose must fall slowly and under medical guidance.

The treatment plan must still control the illness that required steroids. A clinician may also consider another medicine when suitable ⁸.

Never reduce or stop prescribed steroids without the prescriber's help. Stopping too fast can cause dangerously low cortisol levels.

The body needs time to restore its own cortisol production. A slow taper gives the body time to adjust.

Surgery is generally the first treatment for removable endogenous causes ^1,9. The goal is to remove the tissue causing excess hormone production ¹.

The operation depends on the source:

An experienced pituitary surgeon is recommended for Cushing disease ⁹. Surgery may not remove all of the abnormal tissue ³.

The disease can remain after treatment or return later ^3,9. Testing is an important part of diagnosing Cushing’s syndrome ⁹.

More treatment may be needed when surgery is not possible. It may also be needed when cortisol stays high after surgery ⁴.

Further treatment choices may include these options:

Bilateral adrenalectomy means removing both adrenal glands. This operation stops the adrenal glands from making cortisol.

Removing both glands can require lifelong hormone replacement. The replacement may include cortisol and another adrenal hormone called aldosterone.

Cortisol levels may become too low after successful surgery. Cortisol replacement supports the body while hormone control recovers.

Recovery may take six months, one year, or longer. Some people need hormone replacement for life.

An endocrinologist uses blood tests to guide replacement treatment. These tests help show when the dose may be reduced or stopped.

Recovery can involve ongoing physical and emotional needs. Mental health support may help if the illness affects mood or quality of life ⁸.

Lifelong monitoring is needed because the disease may return ⁹. Follow-up checks matter because the condition can recur after surgery ⁹.

Follow-up may address these health concerns:

Long-term effects can include reduced quality of life and other health problems ^1,9. Keep every planned visit, even if many symptoms have improved.

If several signs progress together, contact a healthcare professional. Medical review is important if you use glucocorticoid medicine.

This advice applies to steroids used for asthma, arthritis, and other health problems. Do not wait for every possible symptom to appear.

If a child gains weight while growing slowly, arrange a medical review ⁹. This growth pattern can occur in children with the syndrome ⁴.

If symptoms return after tumor treatment, contact the treating specialist ³. A pituitary tumor can grow back after removal ³.

Bring a full medicine list to your visit. Include pills, injections, inhalers, creams, and other steroid products.

Do not try to treat suspected hormone excess on your own. Do not change a steroid dose without help from the prescriber.

Understanding Cushing's syndrome symptoms, causes, diagnosis, and treatment can help you prepare questions. Early evaluation can help identify excess cortisol and its source.

Treatment depends on whether the cause is medicine or internal hormone production ^5,6. Surgery is often the first choice for a removable internal cause ^1,9.

Long-term follow-up matters because the condition can return after surgery ⁹. If signs progress, speak with a healthcare professional rather than attempting self-treatment.

Never stop prescribed glucocorticoids suddenly. Work with your clinician on any dose change, testing plan, or follow-up care.