Cortisol, Free, Response to ACTH Stimulation

Test Code

16434

CPT Codes
82530 (x3)

Includes

Cortisol, Free: Baseline, 30 minutes, 60 minutes

Preferred Specimen

2 mL serum collected in each of three separate a red-top tube (no gel)

Minimum Volume

0.7 mL for each timed specimen

Other Acceptable Specimens

Plasma collected in: EDTA (lavender-top) tube or PPT potassium (white-top) tube

Instructions

For each timed specimen submitted, each tube must be clearly marked with time drawn. Submit all tubes with one test request form. Draw morning baseline specimen. Administer 250 ug Cortrosyn. Draw additional specimens at 30 and 60 minutes. Grossly hemolyzed specimens are unacceptable.

Note: Cortrosyn (cosyntropin) not supplied by the laboratory. This test cannot be collected at a Patient Service Center.

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 48 hours
Refrigerated: 7 days
Frozen: 2 years

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Gross hemolysis • Received room temperature • Serum Separator Tubes (SST®)

Methodology
Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS) • Equilibrium Dialysis

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Sun-Thurs; Report available: 3-7 days

Clinical Significance

Free Cortisol is useful in the detection of patients with Cushing’s syndrome for whom Free Cortisol concentrations are elevated.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.