Cushing syndrome

Disease Description (Causes and Symptoms)

• Definition summary: Cushing's syndrome is a condition caused by excessive exposure of the body to glucocorticoids (mainly cortisol).
• Causes
  • Exogenous (most common): Long-term use of high-dose glucocorticoids (steroids)
  • Endogenous
    • Excess ACTH secretion (adrenocorticotropic hormone): Mainly an ACTH-secreting tumor of the pituitary gland (Cushing's disease)
    • Excess production by the adrenal glands themselves: Adrenal tumors (adenoma or cancer), etc.
    • Excessive adrenal stimulation caused by tumors that secrete substances resembling ACTH from outside the body (e.g., some lung cancers)
• Pathophysiology summary: Persistent hypercortisolism causes protein breakdown, fat redistribution (fat accumulation in the abdomen and back of the neck), abnormalities in glucose metabolism (insulin resistance and hyperglycemia), increased bone resorption (osteoporosis), skin atrophy, and vascular fragility.
• Main symptoms (representative)
  • Central obesity (abdominal obesity), moon face (a swollen, round face), fat accumulation in the back of the neck (buffalo hump)
  • Muscle weakness (especially reduced strength in the thighs and upper limbs), osteoporosis, increased risk of fractures
  • Hypertension, hyperglycemia/diabetes, dyslipidemia
  • Thinning skin, easy bruising, purple stretch marks (striae), acne, hirsutism
  • Sexual dysfunction, depression and mood changes
• Diagnosis (brief): Based on clinical findings, blood and 24-hour urinary cortisol measurements, late-night salivary cortisol, a low-dose dexamethasone suppression test, and an ACTH test are used to determine whether the condition is ACTH-dependent, followed by imaging such as pituitary MRI or abdominal CT/MRI.

Treatment Methods

• Principles: Remove the cause (surgery if possible) → Correct the hormonal imbalance → Manage complications
• Treatment of exogenous (steroid-induced) disease
  • Gradually reduce the steroid dose in consultation with the treating physician (there is a risk of adrenal insufficiency if it is stopped abruptly)
  • If possible, consider switching to alternative or nonsteroidal treatment
• Treatment of endogenous disease
  • Pituitary gland (Cushing's disease): Transsphenoidal resection of the pituitary tumor (first-line treatment); drug treatment (such as pasireotide and cabergoline) or radiation therapy may be used in cases of recurrence or when surgery is not possible
  • Adrenal tumor: Adrenalectomy (unilateral or total) — additional anticancer and medical treatment is necessary in cancerous cases
  • Ectopic ACTH-secreting tumor: Treatment of the primary site (e.g., the lungs) (surgery or anticancer treatment)
• Drug treatment (preparation before surgery, when surgery is not possible, or as adjunctive treatment)
  • Inhibitors of steroid production: Ketoconazole (注意해야 할 간독성: hepatotoxicity), metyrapone (may increase blood pressure and facial hair growth), mitotane (mainly used for adrenocortical cancer; has strong endocrine effects)
  • Glucocorticoid receptor antagonist: Mifepristone (may be used in patients with hyperglycemia, but biochemical test interpretation can be difficult)
  • Pituitary-targeted treatment: Pasireotide (a somatostatin analog), cabergoline (a dopamine agonist), etc.
• Lifestyle management
  • Weight management, a low-salt diet (for hypertension management), self-monitoring of blood glucose and blood pressure, osteoporosis prevention (calcium, vitamin D, and exercise), infection prevention (take care with wounds and infections)
• Precautions during surgery and treatment (summary)
  • Preoperative control of blood glucose, blood pressure, and electrolytes is necessary
  • Steroid replacement therapy may be necessary after surgery due to temporary or persistent adrenal insufficiency (take it as directed by the physician)
  • Monitoring for medication-specific side effects (hepatotoxicity, electrolyte abnormalities, worsening blood glucose, etc.) is necessary
• Complications and prognosis summary
  • If left untreated, the risks of hypertension, diabetes, cardiovascular disease, osteoporosis, and infection increase
  • Prognosis varies depending on the cause, timing of treatment, and treatment success (early treatment may alleviate complications)

Outpatient Visit Checklist (Including Preparation Items and Example Questions)

• Recommended items to bring
  • A list of all medications currently being taken (including steroids), with doses and dosing schedule
  • Previous test results (blood tests, 24-hour urinary cortisol, dexamethasone suppression test, ACTH levels) and imaging reports (CT/MRI)
  • Records of weight changes, blood pressure measurements, and self-monitoring of blood glucose (if available)
  • The time symptoms began and how they have changed (photos may be helpful: face, skin, abdomen, etc.)
• Important information to tell the healthcare provider during the outpatient visit
  • Whether steroids (including inhaled and topical steroids) have recently been taken and the dose
  • Coexisting conditions such as diabetes, hypertension, and osteoporosis, and medications currently being taken
  • Whether there are plans for pregnancy or whether the patient is pregnant
• Example symptom checklist to provide to the healthcare provider during the outpatient visit
  • Amount of weight gain (how many kilograms recently), nighttime sleep and mood changes, degree of muscle weakness, skin changes (bruising and striae), and changes in menstruation or sexual function

Examples of General Questions to Ask the Doctor

• What is the cause of these symptoms? Is it ACTH-dependent, or is there a problem with the adrenal glands themselves?
• What additional tests are needed in my case, and what treatment options will be available once the results are obtained?
• If surgery is necessary, what are the success rate and recovery process? Will hormone replacement be necessary after surgery?
• What are the side effects of drug treatment, and how will they be monitored?
• What points should I pay particular attention to regarding lifestyle (diet and exercise)?
• How should I prevent fractures and manage bone density?

Examples of Disease-Specific Questions

• To what extent can symptoms of excess cortisol recur even after surgery (adrenalectomy or pituitary surgery)? If recurrence occurs, what is the next treatment plan?
• What steps (schedule) are needed to reduce or stop the steroids I am currently taking, and how will adrenal insufficiency be monitored when they are discontinued?

(Note: The above is general medical information. Because diagnosis and treatment may vary depending on the individual condition, be sure to consult your treating physician.)