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HelpTest Code CORS Cortisol-Stimulation Test
Specimen and Container/Tube
Specimen Type: Serum
Preferred Specimen: Red Top
Other Acceptable specimens: Serum/Gold Top
Specimen Handling and Transport Instructions
UCMC Onsite Instructions:
- Collect specimen per standard collection procedure and send to laboratory immediately.
UCMC Offsite and UC MedLab Outreach Instructions:
- Samples should be centrifuged within 2 hours of collection.
- Centrifuge specimens at >2500 x g for 10 minutes at room temperature.
- Aliquot sample into a plastic tubes containing a minimum of 0.2 mL of specimen.
- Samples must then be sent refrigerated at 2-8oC.
Rejection Criteria
- Common specimen rejected situations include: incorrect specimen type, insufficient volume, missing or incomplete specimen identifiers, incorrect specimen transport, or specimens outside stability limits.
- Specimens that are clotted or grossly hemolyzed.
- Specimens that were transported unspun/whole blood and draw time is greater than 6 hours
Reference Values
Reference ranges for Cortisol that is ordered as part of a specific stimulation/suppression protocol are specific to the protocol utilized by the ordering physician and are therefore subject to ordering physician's interpretation.
Critical Values
|
Analyte |
Unit |
Low |
High |
Age |
|
N/A |
N/A |
N/A |
N/A |
N/A |
CPT Codes
82533
LOINC Codes
12570-8
Volume
Preferred Volume: 0.5 mL
Minimum Volume: 0.2 mL
Specimen Stability
|
Storage Temperature |
Stability |
|
Room Temperature |
24 hours |
|
Refrigerated |
4 days |
|
Frozen |
12 months |
Collection Instructions
Collect specimen per standard laboratory collection procedures.
Test Components
Cortisol
Clinical Indications
The corticotropin-releasing hormone (CRH) stimulation test includes analysis cortisol to evaluate Cushing’s syndrome and adrenal insufficiency. After intravenous administration of CRH, blood may be collected at specified timepoints and analyzed for cortisol and often Adrenocorticotropic Hormone (ACHS).
The test can be used to:
- Evaluate the cause of ACTH-dependent Cushing’s syndrome (with or without vasopressin analogs)
- Discriminate between pseudo-Cushing’s and Cushing’s syndrome
- Discriminate between pituitary or hypothalamic localization of central adrenal insufficiency
- To assess ACTH suppression in patients suspected of primary adrenal mild Cushing’s syndrome.
- Tested as part of insulin tolerance test protocols to measure the impact on growth hormone secretion.
Methodology
Electrochemiluminescence immunoassay (ECLIA) (Roche Diagnostics)
Additional Information
- Results should always be assessed in conjunction with patient's medical history, clinical examination and other findings.
- Falsely elevated concentrations of cortisol may be determined.
- The time of sample collection must be taken into account when interpreting results due to the cortisol secretion circadian rhythm.
- Pregnancy, contraceptives and estrogen therapy give rise to elevated cortisol concentrations. In samples from patients who have been treated with prednisolone, 6-α-Methylprednisolone or prednisone, falsely elevated concentrations of cortisol may be determined.
- During metyrapon tests, 11-deoxycortisol levels are elevated.
- Patients suffering from 21-hydroxylase deficiency exhibit elevated 21-deoxycortisol levels and this can also give rise to falsely elevated cortisol levels.
- Severe stress can also give rise to elevated cortisol levels.
Turnaround Time
Turnaround times are relative to the time the specimen is received in the test laboratory.
STAT Turnaround Time: Not available as STAT test
Routine Turnaround Time: up to 4 hours
Testing Schedule: 24/7
Synonyms/Keyword Search
Corticosteroids, Cortisol, Corticotropin-releasing hormone, CRH, Hydrocortisone
Last Review Date
8/19/2024