Adrenocorticotropic Hormone, Plasma
Use
This test is useful for determining the cause of hypercortisolism and hypocortisolism. It measures the level of adrenocorticotropic hormone (ACTH) in the plasma, providing insight into disorders of cortisol production which affects circulating ACTH concentrations. Such disorders include hypercortisolism conditions like Cushing syndrome, and hypocortisolism conditions such as Addison disease and other forms of adrenal insufficiency.
Special Instructions
For 12 hours before specimen collection, patients should not take multivitamins or dietary supplements containing biotin (vitamin B7). Additionally, a morning specimen collected between 7 a.m. and 10 a.m. is desirable for accurate results. Collection must be with a pre-chilled lavender top (EDTA) tube, transported on ice, centrifuged within 2 hours, and plasma immediately frozen.
Limitations
The assay may be subject to interference by antibodies to mouse or other animal antibodies, or by antibodies to streptavidin or ruthenium, which can cause diagnostic confusion. Patients on ACTH 1-24 medication or taking glucocorticoids may have altered ACTH levels that do not reflect their health status accurately. Results across different assay methods may vary and should not be used interchangeably.
New York Approved
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 2141-0
- 2141-0
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.75 mL
Container
Ice-cooled, lavender top (EDTA) tube; plastic vial for submission
Collection Instructions
Morning specimen is desirable. Collect with a pre-chilled lavender top (EDTA) tube and transport on ice. Centrifuge within 2 hours at refrigerated temperature and immediately separate plasma from cells before freezing.
Patient Preparation
For 12 hours prior, avoid multivitamins or dietary supplements with biotin.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 2 hours |
| Refrigerated | 3 hours |
| Frozen | 28 days |