Test Code LAB1231942 Cortisol/Cortisone, Free, Random, Urine
Specimen Required
Supplies: Urine tube, 10 mL (T068)
Collection Container/Tube: Clean, plastic urine container with no metal cap or glued insert
Submission Container/Tube: Plastic, 10-mL urine tube or clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 10 mL
Collection Instructions: Collect a random urine specimen.
Useful For
Investigating suspected Cushing syndrome (hypercortisolism), when a 24-hour collection is prohibitive (ie, pediatric patients).
Assisting in diagnosing acquired or inherited abnormalities of 11-beta-hydroxy steroid dehydrogenase (cortisol to cortisone ratio)
Diagnosis of pseudohyperaldosteronism due to excessive licorice consumption
This test has limited usefulness in the evaluation of adrenal insufficiency.
This test is not useful for evaluation of hypocorticalism.
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
COCOR | Cortisol, Random, U | No | Yes |
CRETR | Creatinine, Random, U | Yes, (order RCTUR) | Yes |
Reporting Name
Cortisol/Cortisone, Free, Random, USpecimen Type
UrineSpecimen Minimum Volume
5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 14 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
CORTISOL
Males
0-2 years: 3.0-120 mcg/g creatinine
3-8 years: 2.2-89 mcg/g creatinine
9-12 years: 1.4-56 mcg/g creatinine
13-17 years: 1.0-42 mcg/g creatinine
≥18 years: 1.0-119 mcg/g creatinine
Females
0-2 years: 3.0-120 mcg/g creatinine
3-8 years: 2.2-89 mcg/g creatinine
9-12 years: 1.4-56 mcg/g creatinine
13-17 years: 1.0-42 mcg/g creatinine
≥18 years: 0.7-85 mcg/g creatinine
CORTISONE
0-2 years: 25-477 mcg/g creatinine
3-8 years: 11-211 mcg/g creatinine
9-12 years: 5.8-109 mcg/g creatinine
13-17 years: 5.4-102 mcg/g creatinine
18-29 years: 5.7-153 mcg/g creatinine
30-39 years: 6.6-176 mcg/g creatinine
40-49 years: 7.6-203 mcg/g creatinine
50-59 years: 8.8-234 mcg/g creatinine
60-69 years: 10-270 mcg/g creatinine
≥70 years: 12-311 mcg/g creatinine
Use the conversion factors below to convert each analyte from mcg/g creatinine to nmol/mol creatinine:
Conversion factors
Cortisol: mcg/g creatinine x 312=nmol/mol creatinine
Cortisone: mcg/g creatinine x 314=nmol/mol creatinine
Cortisol molecular weight=362.5
Cortisone molecular weight=360.4
Creatinine molecular weight=113.12
Supportive Data
Multiple calibration curves for urinary cortisol and cortisone exhibited consistent linearity and reproducibility in the range of 7 to 828 nmol/L (0.25-30 mcg/dL). Inter-assay coefficients of variation were 7.3% to 16% for mean concentrations of 6 to 726 nmol/L (0.2-26.3 mcg/dL) for cortisol and cortisone. The detection limit was 6 nmol/L (0.2 mcg/dL). Recovery of cortisol and cortisone added to urine was 97% to 123%. The regression equation for the liquid chromatography-tandem mass spectrometry (LC-MS/MS) (y) and high performance liquid chromatography (x) method for cortisol was: y = 1.11x + 0.03 mcg cortisol/24 h (r(2) = 0.992; n = 99). The regression equation for the LC-MS/MS (y) and immunoassay (x) methods for cortisol was: y = 0.66x - 12.1 mcg cortisol/24 h (r(2) = 0.67; n = 99).(1)
Day(s) Performed
Monday through Friday
Report Available
2 to 6 daysSpecimen Retention Time
14 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
82542
82530 - Cortisol
82570 - Creatinine
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CCFR | Cortisol/Cortisone, Free, Random, U | In Process |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
10328 | Cortisol/Creatinine Ratio | 11155-9 |
CRETR | Creatinine, Random, U | 2161-8 |
10329 | Cortisone/Creatinine Ratio | 30511-0 |