Cortisol, Free, 24-Hour Urine with Creatinine, LC/MS/MS

For Specimen Integrity during Extreme Weather see the “Lockbox Usage in Extreme Weather” document at the top of this page.

Test Code

CPT Codes

CPT code 81050 may be added at an additional charge for volume measurement

Preferred Specimen
2 mL of a 24-hour urine collected in a leak-proof urine container, no preservative

Minimum Volume
0.5 mL

Other Acceptable Specimens
24-hour urine in 25 mL 6N HCl, or 10 mL concentrated glacial acetic acid, or in 10 grams boric acid, submitted in a leak-proof urine container

Record 24-hour urine volume on test requisition and urine vial. Reference ranges do not apply to random urine samples.

Transport Container
Urine Container, leak-proof

Transport Temperature
Refrigerated (cold packs)

Specimen Stability
Room temperature: 14 days
Refrigerated: 21 days
Frozen: 90 days

Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)

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 the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Monday-Friday Night
Report available: 3 Days

Reference Range
Cortisol, Free, 24-Hr Urine
 Adult 4.0-50.0
   1-4 Years 0.9-8.2 mcg/24 hrs
   5-9 Years 1.0-30.0 mcg/24 hrs
   10-13 Years 1.0-45.0 mcg/24 hrs
   14-17 Years 3.0-55.0 mcg/24 hrs

Creatinine, 24-Hour Urine
<3 Years Not established
3-8 Years 0.10-0.80 g/24 hours
9-12 Years 0.20-1.40 g/24 hours
13-17 Years 0.40-1.90 g/24 hours
>17 Years 0.50-2.15 g/24 hours

Clinical Significance
Urinary Free Cortisol is useful in the detection of patients with Cushing's syndrome for whom Free Cortisol concentrations are elevated.

Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA
33608 Ortega Highway
San Juan Capistrano, CA 92675-2042

Last Updated: November 29, 2021

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.