How is Cushing’s disease diagnosed?

There is a process to diagnosing Cushing’s disease, and it normally takes time. You may have had symptoms from excessive cortisol levels (known as hypercortisolism) for some time before Cushing’s syndrome is suspected. Once the evaluation of your symptoms might point to Cushing's syndrome, different tests can be performed to confirm the diagnosis of Cushing's syndrome. Thereafter, additional tests are used to determine the cause of the excess cortisol. In the case of Cushing's disease, the cause is a benign pituitary adenoma.1,2

The process of diagnosing Cushing’s disease

There are generally 3 phases in the diagnostic process and you will likely see more than one doctor, including an endocrinologist. 1-7

The process of diagnosing Cushing’s disease

Test Sequence Image

Step 1: Evaluate if you have signs and symptoms of hypercortisolism

When you are evaluated for symptoms of hypercortisolism, you should provide your doctors with a complete medical history, including any conditions you have and the medicines you are taking. If you are taking glucocorticoid medicine, and the doctor thinks this could be causing the signs and symptoms, then testing is not necessary.8
Talk to your doctor if you are experiencing any of the following signs and/or symptoms.6,8

Test if:
Several characteristics and/or symptoms develop and get worse, such as:
  • Red or round (moon-shaped) face
  • Purplish streaks on the body
  • Easy bruising
  • Buildup of fatty tissue in the abdominal area
  • Diabetes
  • Excessive and unusual hair growth in women (called hirsutism)
An adrenal tumor is found during an ultrasound or similar procedure

Step 2: Testing to diagnose Cushing’s syndrome

If your doctor decides that testing is recommended, there are several types of tests that can determine if you have Cushing’s syndrome. This is done by measuring the level of cortisol in your body. These tests should only be done when a form of endogenous hypercortisolism is suspected. If you are diagnosed with Cushing’s syndrome, the doctor will then use additional tests to find the cause.1

Step 3: Testing to diagnose Cushing’s disease

If you are diagnosed with Cushing’s syndrome, the doctor will then use additional tests to find out if your body is producing too much cortisol because of a pituitary tumor (Cushing’s disease), or if it is a different form of Cushing’s syndrome.4

Next, read about the types of tests doctors use

References: 1. Arnaldi G, Angeli A, Atkinson AB, et al. Diagnosis and complications of Cushing’s syndrome: a consensus statement. J Clin Endocrinol Metab. 2003;88:5593-5602. 2. National endocrine and metabolic diseases information service. National Institutes of Health. NIH Publication No. 08-3007. Cushing's Syndrome. http://endocrine.niddk.nih.gov/pubs/cushings/cushings.htm. Published July 2008. Accessed November 10, 2010. 3. Lin DD, Loughlin KR. Diagnosis and management of surgical adrenal diseases. Urology. 2005;66:476-483. 4. Findling J, Nieman L, Vigersky R, eds; The Hormone Foundation. The Hormone Foundation's patient guide to the diagnosis of Cushing's syndrome. http:// www.hormone.org/Resources/patientguides.cfm. Published May 2008. Accessed November 9, 2010. 5. Boscaro M, Barzon L, Fallo F, Sonino N. Cushing's syndrome. Lancet. 2001;357:783-791. 6. Newell-Price J, Bertagna X, Grossman AB, Nieman LK. Cushing's syndrome. Lancet. 2006;367:1605-1617. 7. Nieman LK, Biller BMK, Findling JW, et al. The diagnosis of Cushing’s syndrome: an endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2008;93:1526-1540. 8. The Hormone Foundation’s patient guide to the diagnosis of Cushing’s syndrome. The Hormone Foundation. http://www.hormone.org/resources/patient_guides/upload/mgmt-cushings-syndrome-070609.pdf. Accessed August 4, 2009.