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Test Code CORTDS Dexamethasone Suppression Test, Overnight, Blood

Important Note

Low Dose Dexamethasone Suppression Test  (DST) protocol:   1 mg dexamethasone is taken orally at 11pm.   Then a serum cortisol is collected the following morning at 8 am.  

 

NOTE: The Dexamethasone must be provided to the patient by the ordering physician, either directly or via prescription.  

Additional Codes

LAB2767

Performing Laboratory

Bronson Laboratory, Chemistry - Kalamazoo

Specimen Requirements

Specimen Type: Serum

Container/Tube: Serum gel

Specimen Volume: 5 mL

Specimen Minimum Volume: 0.5 mL serum

Collection Instructions:

1. Dexamethasone will be given by nursing service or physician
at 11 p.m.

2. Patient must fast after midnight.

3. At 8 a.m. the following day, submit a request form for
Cortisol, Plasma or Serum, and indicate “Dexamethasone
Suppression Test, Overnight, Blood.”

Specimen Transport Temperature

Refrigerate

Reference Values

Post-dexamethasone suppression: <1.8 mcg/dL (a.m.) or 80% to 90% lower than basal cortisol value

 

 

Note: Concentration of cortisol in serum
attains adult values by the end of the first week of postnatal life
and thereafter does not vary with age.

Test Classification and CPT Coding

82533