About Us | Privacy | Site Map
May 19, 2013
Font Size
A
A
A
«Previous
1
2
3
4
5
6
...
Next»

Cushing Syndrome (cont.)

Medical Author:
George P Chrousos, MD, FAAP, MACP, MACE
Coauthor:
Shehnaz Shaikh, MD
Medical Editor:
Arthur B Chausmer, MD, PhD, FACP, FACE, FACN, CNS
Medical Editor:
Mary L Windle, PharmD
Medical Editor:
George T Griffing, MD

Exams and Tests for Cushing's Syndrome

  • Measurement of 24-hour cortisol levels: The amount of cortisol excreted in the urine during a 24-hour time period is measured. Values higher than three to four times the upper limit of normal are suggestive of Cushing's syndrome.
  • Overnight 1-mg dexamethasone suppression test: For this test, 1mg of dexamethasone (exogenous corticosteroid) is administered at 11 pm, with measurement of serum cortisol the next morning at 8 am. In healthy individuals, the serum cortisol should be less than 2-3 mcg/dL. Cushing's syndrome may be excluded with a cortisol level less than 1.8 mcg/dL.
  • The 48-hour low-dose dexamethasone suppression test: In many persons, overnight 1mg dexamethasone suppression test may be inconclusive. In such persons, 48-hour low-dose dexamethasone suppression test is performed. In this test, 0.5mg dexamethasone is administered every six hours for eight doses and serum cortisol levels are measured.
  • Corticotropin-releasing hormone (CRH) stimulation test: This test can detect mild corticosteroid excess. It combines the 48-hour low-dose dexamethasone suppression test with CRH stimulation. CRH is administered intravenously two hours after the eighth dose of 0.5mg dexamethasone. Corticosteroid levels are measured 15 minutes after CRH administration. A level of greater than 1.4 mg/dL is suggestive of Cushing's syndrome.
  • Abdominal CT scan: It is recommended if a primary adrenal problem is suggested by the symptoms and clinical examination. The presence of an adrenal mass larger than 4-6 cm in the CT scan raises the possibility that the mass is an adrenal carcinoma.
  • Chest and abdominal CT scans: They should be performed in patients with suspected ACTH production from tumors present elsewhere in the body (for example, lung).
  • Magnetic resonance imaging (MRI) of the brain: If a pituitary source of excess ACTH is suspected, MRI of the brain is performed.

Must Read Articles Related to Cushing Syndrome

Obesity
Obesity More than two-thirds of Americans are overweight, including at least one in five children. Nearly one-third are obese. Obesity is on the rise in our society ...learn more >>
See the Entire Cushing Syndrome Topic Guide »
Print
Print
Privacy Policy

Women's Health

Find out what women really need.

Please acknowledge your agreement




Read What Your Physician is Reading on Medscape

Cushing Syndrome »

Cushing syndrome is caused by prolonged exposure to elevated levels of either endogenous glucocorticoids or exogenous glucocorticoids.

Read More on Medscape Reference »


Featured Topics

Thyroid & Metabolism Topics

Medical Dictionary


or A-Z List
Use Pill Finder Find it Now

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies