Cortisol, LC/MS, Saliva, 3 Samples
Test Summary
Salivary cortisol level, particularly late-night salivary cortisol (LNSC) level, is useful in screening for endogenous Cushing syndrome. Two or more positive results of LNSC tests may be used to confirm Cushing syndrome. LNSC measurement may also be used to monitor for recurrence of Cushing disease [1].
Normally, the secretion of cortisol has a circadian rhythm. Patients with Cushing syndrome often lose the late-night circadian nadir. Therefore, an elevated LNSC level may provide initial evidence for Cushing syndrome. Two or more positive results of LNSC tests may establish the diagnosis of Cushing syndrome if non-neoplastic hypercortisolism (pseudo-Cushing syndrome) is excluded. Because saliva is convenient to collect, LNSC testing is especially useful for individuals who need to provide multiple specimens over time for the evaluation of cyclic Cushing syndrome [1].
Annual LNSC testing is recommended to monitor for the recurrence of Cushing disease after pituitary surgery. LNSC testing may also be used in assessing treatment outcomes in patients receiving medical therapy for Cushing disease [1].
Non-neoplastic hypercortisolism caused by obesity, psychiatric disorders, alcohol use disorder, and polycystic ovary syndrome may increase LNSC levels. LNSC testing should not be used to screen for Cushing syndrome in individuals without normal day and night cycles. LNSC testing has low sensitivity in patients with adrenal tumors [1].
Other tests, such as urinary free cortisol (test code 14534) and dexamethasone suppression test (test code 6921), may also be used to screen for Cushing syndrome. Choice of tests should be individualized based upon clinical scenarios [1].
The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.
Reference
1. Fleseriu M, et al. Lancet Diabetes Endocrinol. 2021;9(12):847-875.
Aliases
- N/A
Specimen Collection
Special Instructions
Preferred Specimen
Minimum Volume
Instructions
b. Remove the swab from the Salivette(R).
c. Place the swab in the mouth, e.g. in your cheek, where it should remain for 2 min without chewing. If an extremely small amount of saliva is produced, leave the swab in the mouth for longer.
d. Return the swab with the absorbed saliva to the Salivette(R).
e. Replace the stopper.
f. Refrigerate the Salivette(R) immediately.
Patient Preparation
Storage
Transport Temperature
Specimen Stability
- Room Temperature = 3 days
- Refrigerated = 21 days
- Frozen = 180 days
Limitations
Other Acceptable Specimens
Unacceptable Specimens
Order Code
EPIC (Premier) Code
Includes
CPT Code
- 82530 (x3)
Billing Code
- 500322
CPT Statement
Methodology
FDA Status
Physician Attestation of Informed Consent
Testing Laboratory
33608 Ortega Highway
San Juan Capistrano CA, 92675
Department
Reference Range
Setup Schedule / Expected Turnaround Time
Specimen Collection
Special Instructions
Preferred Specimen
Minimum Volume
Instructions
b. Remove the swab from the Salivette(R).
c. Place the swab in the mouth, e.g. in your cheek, where it should remain for 2 min without chewing. If an extremely small amount of saliva is produced, leave the swab in the mouth for longer.
d. Return the swab with the absorbed saliva to the Salivette(R).
e. Replace the stopper.
f. Refrigerate the Salivette(R) immediately.
Patient Preparation
Storage
Transport Temperature
Specimen Stability
- Room Temperature = 3 days
- Refrigerated = 21 days
- Frozen = 180 days