Test Code LAB7489 Cortisol, Saliva
Additional Codes
SALCT
Useful For
Screening for Cushing syndrome
Diagnosis of Cushing syndrome in patients presenting with symptoms or signs suggestive of the disease
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SalivaNecessary Information
Collection time is required.
Specimen Required
Patient Preparation:
1. Do not brush teeth before collecting specimen.
2. Do not eat or drink for 15 minutes prior to specimen collection.
Supplies: Cortisol, Saliva Collection Kit (T514)
Container/Tube: SARSTEDT Salivette
Specimen Volume: 1.5 mL
Collection Instructions:
1. Provide patient with a Saliva Collection Kit (Salivette) containing the Cortisol - Saliva Collection Instructions and ask them to follow the instructions as written.
2. Instruct patient to collect specimen between 11 p.m. and midnight and record collection time on the Cortisol - Saliva Collection Instructions sheet.
3. Instruct patient to return Cortisol - Saliva Collection Instructions with the appropriately labeled Salivette to the laboratory.
Additional Information:
1. Reference values are also available for an 8 a.m. (7 a.m.-9 a.m.) or a 4 p.m. (3 p.m.-5 p.m.) collection, however, the 11 p.m. to midnight collection is preferred.
2. If multiple specimens are collected, submit each vial under a separate order.
Specimen Minimum Volume
0.6 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Saliva | Refrigerated (preferred) | 28 days | |
Frozen | 60 days | ||
Ambient | 28 days |
Reference Values
7 a.m.-9 a.m.: 100-750 ng/dL
3 p.m.-5 p.m.: <401 ng/dL
11 p.m.-midnight: <100 ng/dL
Day(s) Performed
Monday through Friday
CPT Code Information
82533
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SALCT | Cortisol, Saliva | 2142-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
84225 | Cortisol, Saliva | 2142-8 |
23612 | AM Cortisol | 58674-3 |
23613 | PM Cortisol | 58668-5 |
23614 | Midnight Cortisol | 58642-0 |
Interpretation
Cushing syndrome is characterized by increased salivary cortisol levels, and late-night saliva cortisol measurements may be the optimum test for the diagnosis of Cushing syndrome. It is standard practice to confirm elevated results at least once. This can be done by repeat late-night salivary cortisol measurements, midnight blood sampling for cortisol (CORT / Cortisol, Serum), 24-hour urinary free cortisol collection (CORTU / Cortisol, Free, 24 Hour, Urine), or overnight dexamethasone suppression testing. Upon confirmation of the diagnosis, the cause of hypercortisolism, adrenal versus pituitary versus ectopic adrenocorticotropic hormone production, needs to be established. This is typically a complex undertaking, requiring dynamic testing of the pituitary adrenal axis and imaging procedures. Referral to specialized centers or in-depth consultation with experts is strongly recommended.
Method Description
Deuterated cortisol (d3-cortisol) is added to 0.1 mL sample as an internal standard. Cortisol and d3-cortisol are extracted from the specimen using online turbulent flow high-performance liquid chromatography and analyzed by liquid chromatography-tandem mass spectrometry using multiple reaction monitoring in positive mode. The following transitions are used for analysis: Cortisol: 363.3/121.1; d3-cortisol: 366.3/121.1.(Taylor RL, Machacek DA, Singh RJ. Validation of a high-throughput liquid chromatography-tandem mass spectrometry method for urinary cortisol and cortisone. Clin Chem. 2002;48:1511-1519)
Report Available
2 to 5 daysSpecimen Retention Time
2 weeksReject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Secondary ID
84225Special Instructions
Forms
If not ordering electronically, complete, print, and send General Request (T239)