Adrenocorticotropic Hormone (ACTH), Plasma

Casandra

Casandra Test Code LC17856Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 004440CPT Code 82024

Adrenocorticotropic Hormone (ACTH), Plasma

Also known as: ACTH, Corticotropin

Clinical Use

Order Test

Use

Pituitary function test useful in the differential diagnosis of Cushing syndrome, ectopic ACTH syndrome (eg, carcinoma of lung, islet cell tumors, carcinoid tumors, medullary carcinoma of thyroid), Addison disease, hypopituitarism, and ACTH-producing pituitary tumors (eg, Nelson syndrome)

Special Instructions

Instructions for suppression/stimulation tests involving ACTH measurement can be found in the online endocrine appendices. This test may exhibit interference when the sample is collected from a person consuming a high dose of biotin. Patients should be cautioned to stop biotin intake at least 72 hours before sample collection.

Limitations

ACTH secretion is pulsatile; multiple specimen collections may be required. Non-siliconized tubes can lead to low results. Monoclonal mouse antibodies and high titers of antibodies to streptavidin and ruthenium can cause interference. Collection time is crucial due to diurnal variation.

Test Details

Methodology

Immunoassay (ECLIA)

Biomarkers

Adrenocorticotropic Hormone

Analyte

ACTH Level • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Order Codes

2141-0

Result Codes

2141-0

Result Turnaround Time

1-2 days

Specimen

Plasma

Volume

0.8 mL

Minimum Volume

0.3 mL

Container

Plastic or siliconized glass lavender-top (EDTA) tube

Collection Instructions

ACTH should be drawn between 7 a.m. and 10 a.m. Collect into iced plastic or siliconized glass lavender-top (EDTA) tube, noting the time. After venipuncture, immerse tubes in an ice bath. Separate plasma by centrifugation within one hour, transfer to a Labcorp PP transpak frozen purple tube, and freeze immediately.