ACTH, Plasma

Test Code
211

Preferred Specimen
1.5 mL plasma collected in an EDTA (lavender-top) tube

Minimum Volume
0.5 mL

Other Acceptable Specimens
PPT potassium EDTA (white-top) tube

Instructions
Draw specimen between 7 a.m. and 10 a.m. If drawn at any other time, the reference ranges do not apply.

Centrifuge immediately after collection to separate plasma from cells. Transfer plasma to a plastic specimen transport container and mark the specimen type as plasma on the container. Freeze immediately.

Transport Temperature
Frozen

Specimen Stability
Room temperature: 16 hours
Refrigerated: 24 hours
Frozen: 28 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Received thawed

Methodology
Immunoassay (IA)

Limitations
With patients receiving more than 5mg/day of biotin, a sample should be taken no sooner than eight hours after previous dose. Patients treated with monoclonal mouse antibodies may have inaccurate results. High titer of antibodies such as streptavidin and ruthenium may cause interference. Due to its correlation with cortisol levels, ACTH concentration is affected by stress. Any single measure may be within the reference range for patients with increased production (Cushing's disease) or minimal production of ACTH.

Reference Range
<3 Years Not established
3-17 Years 9-57 pg/mL
≥18 Years 6-50 pg/mL


Clinical Significance
Determination of ACTH is useful in differentiating between primary and secondary adrenocortical hypo- and hyperfunctional disorders: Addison's disease, Cushing's syndrome, adrenal carcinoma, ectopic ACTH syndrome, and adrenal nodular hyperplasia.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153



The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.