Dexamethasone Suppression Test (DST), 1 Specimen

Test Code
6921


CPT Codes
82533

Preferred Specimen
1 mL serum 


Minimum Volume
0.5 mL


Instructions
The ordering physician should administer 1 mg Dexamethasone between 11:00 p.m. and midnight. Draw serum for cortisol testing between 7:00-9:00 a.m. the next morning. Mark tube with time and date drawn.

Note: Dexamethasone not supplied by the laboratory.


Transport Container
Serum separator tube (SST)


Transport Temperature
Room temperature


Specimen Stability
Room temperature: 7 days
Refrigerated: 7 days
Frozen: 28 days


Methodology
Immunoassay (IA)

Setup Schedule
Mon-sat


Report Available
1 day


Reference Range
8 A.M. Specimen
<2.0 mcg/dL Normal response
2.0-10.0 mcg/dL Equivocal
>10.0 mcg/dL High probability of Cushing's syndrome
Further diagnostic tests must be performed to confirm the diagnosis and determine etiology. Values >2.0 mcg/dL can be seen in endogenous depression and pseudo-Cushing's (alcoholism).


Clinical Significance
Cortisol is increased in Cushing's Disease and decreased in Addison's Disease (Adrenal insufficiency).


Performing Laboratory
Quest Diagnostics-Pittsburgh Lab
875 Greentree Road
Pittsburgh, PA 15220-3508




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.