Dexamethasone

Test Code

DEXA

CPT Codes
80299

Preferred Specimen

0.85 mL serum collected in a red-top tube (no gel)

Minimum Volume

0.25 mL

Instructions

Draw specimen between 8:00 a.m. and 10:00 a.m.

Please note: SST tubes are unacceptable, and will cause interference with the results

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 72 hours
Refrigerated: 14 days
Frozen: 90 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Gross hemolysis • Grossly lipemic • Serum separator tube (SST)

Methodology
Chromatography/Mass Spectrometry

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Mon; Report available: 3-11 days

Reference Range

Baseline	Less than 20 ng/dL
1 mg dexamethasone overnight	180-550 ng/dL (8:00-10:00 AM)

Clinical Significance

Measurement of Dexamethasone is useful in assuring compliance with Dexamethasone treatment and documenting adequate dosing during such procedures as the Dexamethasone Suppression Test used in the differential diagnosis of Cushing's syndrome.

Performing Laboratory
Quest Diagnostics Nichols Inst San Juan Capistrano
33608 Ortega Highway
San Juan Capistrano, CA 92690-6130

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.