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 - Serum Separator (SST) Tube(s) - Full Tube Collection Serum Separator (SST) Tube(s) - Full Tube Collection Manufacturer: Becton Dickinson Catalogue #: 367986

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.

Specimen Stability:

Ambient: 72 hours

Refrigerated: 7 days

Frozen: 28 days

Referral:

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

Referred Out Location:

Specimen referred from HSC-MS5 to:

Mayo Clinic Laboratories

3050 Superior Dr. NW

Rochester, MN 55901

Phone: 800-533-1710

Test ID: DEXA

Requisition:

Reference Values:

Reference Intervals:

Baseline: <30 ng/dL

8:00 a.m. following 1 mg Dexamethasone previous evening: >100 ng/dL

Method of Analysis: LC-MS/MS

Availability:

Within 2 Weeks