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).

For routine dexamethasone suppression test protocol, see CORTISOL (OVERNIGHT DEXAMETHASONE SUPPRESSION TEST) - (P) or CORTISOL - (P)

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