Lab Information Manual

Laboratory:

Clinical Biochemistry (SENDOUTS)

Test Name:

DEXAMETHASONE by LC-MS/MS - (S)

Test Code: MIS8

Clinical Information:

Test Indications: This test is to measure dexamethasone drug levels post dexamethasone suppression test (DST).

Assessment of compliance of dexamethasone suppression testing protocol.

Assessment of dexamethasone levels after DST may be aid in cases with post DST morning cortisol values of 50-138 nmol/L.

Test Approval Requirements: Test is restricted to endocrinologists upon test approval. F260-11-02 Biochemistry Approval for Test Referral Form

Collection Devices:

Preferred Device:	1 - Serum Tube(s), NO GEL - Full Tube Collection Serum Tube(s), NO GEL - Full Tube Collection Manufacturer: Becton Dickinson Catalogue #: 366430
Alternate Device:	1 - Microtainer(s) - Plain Serum, NO GEL (0.5 mL) to fill line Microtainer(s) - Plain Serum, NO GEL (0.5 mL) to fill line Manufacturer: Becton Dickinson & Company Catalogue #: 365963

Specimen Required:

Serum: 1.0 mL

Collection Information:

1. Draw blood between 7:00 a.m. and 9:00 a.m. the morning following an evening dose. Collect at the same time as cortisol specimen.

2. Centrifuge and aliquot serum within one hour of collection.

Special Processing:

Reject Criteria:

Gross hemolysis

Grossly lipemic

Serum separator tube (SST)
Specimen Stability:

Ambient: 72 hours

Refrigerated: 14 days

Frozen: 90 days

Referral:

Shipping & Storage: Store and ship frozen. Avoid repeated freeze-thaw cycles.

Referred Out Location:

Specimen referred from HSC-MS5 to:

In-Common Laboratories (ICL)
57 Gervais Drive
North York, Ontario
M3C 1Z2
Telephone: (416) 422-3000
Test ID: DEXA
Testing Location: Quest Diagnostics

https://testdirectory.questdiagnostics.com/test/test-detail/29391/dexamethasone?q=29391&cc=MET

Requisition:

Reference Values:

Reference Intervals:

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

Method of Analysis: LC-MS/MS

Availability:

Within 2 Weeks