Test Code CORT Cortisol, Serum
Reporting Name
Cortisol, SUseful For
Discrimination between primary and secondary adrenal insufficiency
Differential diagnosis of Cushing syndrome
This test is not recommended for evaluating response to metyrapone.
Performing Laboratory

Specimen Type
SerumOrdering Guidance
The preferred screening test for Cushing syndrome measures 24-hour urinary free cortisol. Order CORTU / Cortisol, Free, 24 Hour, Urine.
For confirming the presence of synthetic steroids, order SGSS / Synthetic Glucocorticoid Screen, Serum.
For patients taking exogenous glucocorticoids, order CORTU / Cortisol, Free, 24 Hour, Urine.
For evaluating response to metyrapone, order DCORT / 11-Deoxycortisol, Serum.
For evaluation of congenital adrenal hyperplasia, the following tests provide better, accurate, and specific determination of the enzyme deficiency:
-DCORT / 11-Deoxycortisol, Serum
-OHPG / 17-Hydroxyprogesterone, Serum
-DHEA_ / Dehydroepiandrosterone (DHEA), Serum
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.6 mL serum
Collection Instructions:
1. Morning (8 a.m.) and afternoon (4 p.m.) specimens are preferred.
2.Within 2 hours of collection, centrifuge the specimen.
3. For red-top tubes aliquot the serum into a plastic vial after centrifugation.
Additional Information:
1. Include time of collection.
2. If multiple specimens are collected, send separate order for each specimen.
Specimen Minimum Volume
Serum: 0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Serum | Refrigerated (preferred) | 14 days |
Frozen | 90 days | |
Ambient | 7 days |
Reference Values
0-<3 months: 1.1-19 mcg/dL
3 months-<12 months: 2.6-23 mcg/dL
12 months-<13 years: 2.2-13 mcg/dL
13 years-<16 years: 3.0-17 mcg/dL
16 years-<18 years: 3.8-19 mcg/dL
≥18 years:
a.m.: 7-25 mcg/dL
p.m.: 2-14 mcg/dL
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 Saturday
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
82533
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CORT | Cortisol, S | 87429-7 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
CORTP | Cortisol, S | 83088-5 |
CAM | AM Result | 9813-7 |
CPM | PM Result | 9812-9 |
Report Available
1 to 3 daysReject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Gross icterus | OK |
Method Name
Immunoenzymatic Assay