Adrenocorticotropic Hormone (ACTH), Plasma
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Determining the cause of hypercortisolism and hypocortisolism
Automated Chemiluminescent Immunometric Assay
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Adrenocorticotropic Hormone, P
ACTH (Adrenocorticotropic Hormone)
Adrenal Corticotropin Hormone
Adrenal Corticotropin Hormone
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Collection Container/Tube: Ice-cooled, lavender top (EDTA)
Submission Container: Plastic vial
Specimen Volume: 1 mL
1. Spin down in a refrigerated centrifuge and immediately separate plasma from cells.
2. Morning (6 a.m.-10:30 a.m.) specimen is desirable.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Mild OK; Gross reject
Mild OK; Gross OK
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Plasma EDTA||Frozen||14 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Adrenocorticotropic hormone (ACTH), the primary stimulator of adrenal cortisol production, is synthesized by the pituitary in response to corticotropin-releasing hormone (CRH), which is released by the hypothalamus. Plasma ACTH and cortisol levels exhibit peaks (6-8 a.m.) and nadirs (11 p.m.).
Cortisol, the main glucocorticoid, plays a central role in glucose metabolism and in the body's response to stress. Only a small percentage of circulating cortisol is biologically active (free form), with the majority of cortisol inactive (protein bound). Cortisol is inactivated in the liver and excreted in the urine as conjugated compounds (largely 17-hydroxysteroids). Urine free cortisol levels reflect circulating free plasma cortisol levels.
Disorders of cortisol production:
- Cushing disease (pituitary ACTH-producing tumor)
- Ectopic ACTH-producing tumor
- Ectopic CRH
- Adrenal cortisol-producing tumor
- Adrenal hyperplasia (non-ACTH dependent, autonomous cortisol-producing adrenal nodules)
-Addison disease-primary adrenal insufficiency
-Secondary adrenal insufficiency
-Congenital adrenal hyperplasia-defects in enzymes involved in cortisol synthesis
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
10-60 pg/mL (a.m. draws)
No established reference values for p.m. draws
Pediatric reference values are the same as adults, as confirmed by peer reviewed literature.
Petersen KE: ACTH in normal children and children with pituitary and adrenal diseases. I. Measurement in plasma by radioimmunoassay-basal values. Acta Paediatr Scand 1981;70:341-345
In a patient with hypocortisolism, an elevated adrenocorticotropic hormone (ACTH) indicates primary adrenal insufficiency, whereas a value that is not elevated is consistent with secondary adrenal insufficiency from a pituitary or hypothalamic cause.
In a patient with hypercortisolism (Cushing syndrome), a suppressed value is consistent with a cortisol-producing adrenal adenoma or carcinoma, primary adrenal micronodular hyperplasia, or exogenous corticosteroid use.
Normal or elevated ACTH in a patient with Cushing syndrome puts the patient in the ACTH-dependent Cushing syndrome category. This is due to either an ACTH-producing pituitary adenoma or ectopic production of ACTH (bronchial carcinoid, small cell lung cancer, others). Further diagnostic studies such as dexamethasone suppression testing, corticotropin-releasing hormone stimulation testing, petrosal sinus sampling, and imaging studies are usually necessary to define the ACTH source.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
In very rare instances of the ectopic adrenocorticotropic hormone (ACTH) syndrome, the elevated ACTH may be biologically active but not detected by the immunometric assay.
Patients taking glucocorticoids may have suppressed levels of ACTH with an apparent high level of cortisol. This may be due to cross-reactivity with the cortisol immunoassays. If exogenous Cushing is suspected, a cortisol level determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) (eg, COR/500052 Cortisol, Serum, LC-MS/MS) should be used with the ACTH level for the interpretation.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Demers LM: In Tietz Textbook of Clinical Chemistry and Molecular Diagnostics, 2006; pp 2014-2027
2. Petersen KE: ACTH in normal children and children with pituitary and adrenal diseases I. Measurement in plasma by radioimmunoassay-basal values. Acta Paediatr Scan 1981;70:341-345
Method Description Describes how the test is performed and provides a method-specific reference
The IMMULITE 2000 adrenocorticotropic hormone (ACTH) is a solid-phase, sequential immunoassay. The patient sample is incubated with a bead coated with a mouse monoclonal antibody to ACTH. A second (rabbit) antibody to ACTH, which has been conjugated to alkaline phosphatase is then added. The sample forms an antibody-sandwich complex attached to the bead. After washing, substrate is added. The substrate undergoes hydrolysis in the presence of alkaline phosphatase to yield an unstable intermediate that results in the sustained emission of light. The photon output is directly proportional to the concentration of ACTH in the sample.(Package insert: IMMULITE 2000 ACTH PIL2KAC-15, Siemens Medical Solutions Diagnostics, 2008-07-29)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 5 a.m.-12 a.m., Saturday; 6 a.m.-6 p.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Same day/1 day
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|ACTH||Adrenocorticotropic Hormone, P||2141-0|