TEST ID DEXA Dexamethasone, Serum
Reporting Name
Dexamethasone, SSpecimen Type
SerumOrdering Guidance
To detect the metabolite of fluticasone or Flonase, order 17BFP / Fluticasone 17-Beta-Carboxylic Acid, Random, Urine.
For synthetic glucocorticoid analyte screen, order SGSS / Synthetic Glucocorticoid Screen, Serum.
Specimen Required
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 2 mL
Collection Instructions:
1. Draw blood between 7:30 a.m. and 9:00 a.m. the morning following an evening dose.
2. Centrifuge and aliquot serum into plastic vial within one hour of collection and freeze immediately.
Specimen Minimum Volume
0.6 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Frozen (preferred) | 28 days | |
Refrigerated | 7 days | ||
Ambient | 72 hours |
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Reference Values
Baseline: <30 ng/dL
8:00 a.m. following 1 mg Dexamethasone, previous evening: >100 ng/dL
8:00 a.m. following 8 mg Dexamethasone, (4 x 2 mg doses) previous day: >800 ng/dL
Day(s) Performed
Tuesday, Thursday
Report Available
2 to 6 daysSpecimen Retention Time
3 monthsPerforming Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
80299
Forms
If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.
Useful For
Confirming the presence of dexamethasone in serum
Confirming the cause of secondary adrenal insufficiency
This test is not useful as the sole basis for a diagnosis or treatment decisions.