Lab Test

Cortisol Level

Serum Cortisol, Hydrocortisone

Test Codes

Antrim #17059, EPIC: LAB5032, CORT

Department

Chemistry

Instructions

Note: Cortisol Level is no longer available for testing on plasma specimens. Serum specimens only.

Specimen Collection Criteria

Collect: One Gold-top SST tube.

Contact the Laboratory for the acceptability of other tube types.
Record exact time of collection on the tube.

Physician Office/Draw Specimen Preparation

Let SST specimens clot 30–60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2–8°C or 36–46°F) the centrifuged SST tube within two hours of collection. (Minimum: 1.0 mL)

Preparation for Courier Transport

Transport: Centrifuged SST tube, refrigerated (2–8°C or 36–46°F). (Minimum: 1.0 mL)

Rejection Criteria

Red-top tubes with serum not separated from cells within two hours of collection.

Specimens not collected and processed as indicated.

In-Lab Processing

Let SST specimens clot 30–60 minutes. Centrifuge SST tubes or Microtainers® to separate serum from cells. Deliver immediately to the appropriate testing station.

Storage

Specimen Stability for Testing:

Centrifuged SST Tubes and Microtainers® with Separator Gel
Room Temperature (20–26°C or 68–78.8°F): 8 hours
Refrigerated (2–8°C or 36–46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable

Red-top Tubes and Microtainers® without Separator Gel
Room Temperature (20–25°C or 68–77°F): 2-4 hours
Refrigerated (2–8°C or 36–46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable

Serum Specimens (Pour-Overs)
Room Temperature (20–26°C or 68–78.8°F): 8 hours
Refrigerated (2–8°C or 36–46°F): 7 days
Frozen (-20°C/-4°F or below): 7 days

Specimen Storage in Department Prior to Disposal:

Refrigerated (2–8°C or 36–46°F): 7 days

Laboratory

Dearborn Chemistry Laboratory
Royal Oak Automated Chemistry Laboratory
Troy Chemistry Laboratory

Performed

Sunday – Saturday, 24 hours a day.
Results available within 24 hours of receipt in the Laboratory.

Reference Range

2.9–19.4 mcg/dL

Test Methodology

Chemiluminescence Immunoassay.

Interpretation

  • Acute stress (including hospitalization and surgery), alcoholism, depression, and many drugs (e.g., exogenous corticosteroids, anticonvulsants) can alter the normal diurnal variation, affect response to suppression/stimulation tests, and cause elevated baseline levels.
  • Increased cortisol levels may be seen in pregnancy and in women taking oral contraceptives. This is due to increased binding proteins. The free cortisol in these cases is normal.
  • 11-Deoxycortisol and Cortisone have a cross reactivity of 23% and 31% respectively. Prednisolone, 6-methy Prednisolone and Prednisone have a cross reactivity of 109%, 26% and 34% respectively.

Clinical Utility

Cortisol is the main glucocorticoid (representing 75–90% of the plasma corticosteroids). It plays a central role in glucose metabolism, in the body's response to stress, and in protein catabolism. Cortisol is elevated in Cushing's disease (pituitary adenoma producing ACTH), in cortisol-secreting adenomas and carcinomas of the adrenal gland and in ectopic ACTH-secreting tumors. Cortisol levels are decreased in primary adrenal insufficiency (increased ACTH), secondary adrenal insufficiency (decreased ACTH) and in congenital adrenal hyperplasia. This test is not useful for following dosage of exogenous, synthetic corticosteroids.

CPT Codes

82533
LOINC: 2143-6, 9813-7, AM 51494-3, 9813-7, PM 51493-7, 9812-9, Midnight 51492-7

Contacts

Last Updated

12/5/2022

Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.