Dexamethasone Suppression 1, Cushings

Test Code

DEXS1

Alias/See Also

Cortisol

CPT Codes
82533

Includes

Cortisol Post Dose

DSDOS: Dose given
DSTIM: Dose Time
PCORT: Cortisol Post
D1CON: Consultation comment if indicated

Patient Preparation

Patient is given an oral dose of 1mg. Dexamethasone at 2300 h.
Collect a blood specimen for cortisol level at 0800 (8 am) on the next morning.

Setup Schedule

24x7

Reference Range

3.09-22.40 ug/dL

Clinical Significance

Dexamethasone suppression tests are used to assess the status of the hypothalamic-pituitary-adrenal (HPA) axis and for the differential diagnosis of adrenal hyperfunction. The low-dose, 1 mg dexamethasone suppression test (which is what we offer) is used to assess nonsuppressible cortisol production production by adrenal lesions. Its major clinical use is to differentiate patients with Cushion's syndrome of any cause from patients who do not have Cushing's syndrome. The low dose suppression test has also been used to identify and characterize the endogenous form of depression.

By causing elevation of serun cortisol, stress will affect the results of this procedure (false positive; failure to suppress). The patient should be instructed to relax as much as possible. False positives can also be seen in acute and chronic illness, alcoholism, depression, morbid obesity, and drugs including estrogen, phenytoin, phenobarbitol, primidone. Results are not valid if the patient is taking ACTH or glucocorticoids.

Performing Laboratory
CRMC Laboratory (for cortisol testing)

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.