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HelpTest Code COCOU Cortisol/Cortisone, Free, 24 Hour, Urine
Reporting Name
Cortisol/Cortisone, Free, UUseful For
Screening test for Cushing syndrome (hypercortisolism)
Assisting in diagnosing acquired or inherited abnormalities of 11-beta-hydroxy steroid dehydrogenase (cortisol to cortisone ratio)
Diagnosis of pseudo-hyperaldosteronism due to excessive licorice consumption
This test has limited usefulness in the evaluation of adrenal insufficiency.
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
UrineNecessary Information
24-Hour volume (in milliliters) is required.
Specimen Required
Supplies: Urine Tubes, 10-mL (T068)
Submission Container/Tube: Plastic, urine tube (T068)
Specimen Volume: 5 mL
Collection Instructions:
1. Add 10 g of boric acid as preservative at start of collection.
2. Collect urine for a full 24 hours (required) and record the total volume.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.
Specimen Minimum Volume
3 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 14 days |
| Frozen | 28 days | |
| Ambient | 72 hours |
Special Instructions
Reference Values
CORTISOL
0-2 years: not established
3-8 years: 1.4-20 mcg/24 h
9-12 years: 2.6-37 mcg/24 h
13-17 years: 4.0-56 mcg/24 h
≥18 years: 3.5-45 mcg/24 h
CORTISONE
0-2 years: not established
3-8 years: 5.5-41 mcg/24 h
9-12 years: 9.9-73 mcg/24 h
13-17 years: 15-108 mcg/24 h
≥18 years: 17-129 mcg/24 h
Use the factors below to convert each analyte from mcg/24 h to nmol/24 h:
Conversion factors
Cortisol: mcg/24 hours x 2.76=nmol/24 h (molecular weight=362.5)
Cortisone: mcg/24 hours x 2.78=nmol/24 h (molecular weight=360)
For International System of Units (SI) conversion for Reference Values, see www.mayocliniclabs.com/order-tests/si-unit-conversion.html
Day(s) Performed
Monday through Friday
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82530-Cortisol; free
82542
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| COCOU | Cortisol/Cortisone, Free, U | 101319-2 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 8546 | Cortisol, U | 14158-0 |
| 10327 | Cortisone, U | 14044-2 |
| TM93 | Collection Duration (h) | 13362-9 |
| VL47 | Volume (mL) | 3167-4 |
Cautions
Acute stress (including hospitalization and surgery), alcoholism, depression, and many drugs (eg, exogenous cortisone, anticonvulsants) can obliterate normal diurnal variation, affect response to suppression/stimulation tests, and increase baseline levels.
This methodology (liquid chromatography tandem mass spectrometry) eliminates analytical interferences including carbamazepine (Tegretol) and synthetic corticosteroids.
This test has limited usefulness in the evaluation of adrenal insufficiency.
Improper collection may alter results. For example, a missed morning collection may result in false-negative tests; an extra morning collection (ie, >24 hours) may give false-positive results.
Renal disease (decreased clearance) may cause falsely low values.
Values may be elevated to twice normal in pregnancy.
Patients with exogenous Cushing syndrome caused by ingestion of hydrocortisone will not have suppressed cortisol and cortisone values.
Report Available
2 to 6 daysReject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.NY State Approved
YesMethod Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)