NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Determining biologically active levels of prolactin, in asymptomatic patients with elevated prolactin levels
Ruling out the presence of macroprolactin
Profile Information A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.
|Test ID||Reporting Name||Available Separately||Always Performed|
|TOPRL||Prolactin,Total,S||Yes, (order PRL)||Yes|
TOPRL/28067: Electrochemiluminescent Immunoassay
PEGPR/28068: Polyethylene Glycol (PEG) Precipitation Followed by Electrochemiluminescent Immunoassay
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
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.
Preferred: Red top
Acceptable: Serum gel
Specimen Volume: 1 mL
Collection Instructions: Spin down and separate serum from clot.
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.
|Serum||Refrigerated (preferred)||14 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Prolactin is secreted by the anterior pituitary gland under negative control by dopamine, which is secreted by the hypothalamus. The only physiological function of prolactin is the stimulation of milk production. In normal individuals, the prolactin level rises in response to physiologic stimuli such as nipple stimulation, sleep, exercise, sexual intercourse, and hypoglycemia. Pathologic causes of hyperprolactinemia include prolactin-secreting pituitary adenoma (prolactinoma), diseases of the hypothalamus, primary hypothyroidism, section compression of the pituitary stalk, chest wall lesions, renal failure, and ectopic tumors.
Hyperprolactinemia may also be caused by the presence of a high-molecular–mass complex of prolactin called macroprolactin (typically due to prolactin bound to immunoglobulin). In this situation, the patient is asymptomatic. Hyperprolactinemia attributable to macroprolactin is a frequent cause of misdiagnosis and mismanagement of patients. Macroprolactin should be considered if, in the presence of elevated prolactin levels, signs and symptoms of hyperprolactinemia are absent, or pituitary imaging studies are not informative.
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.
< or =18 years: not established
>18 years: 4.0-15.2 ng/mL
< or =18 years: not established
>18 years: 4.8-23.3 ng/mL
Percent of the precipitated (complexed) prolactin fraction of the total prolactin <50% (considered negative for macroprolactin)
Unprecipitated prolactin levels are expected to be within the total prolactin reference range.
When the percentage of the precipitated prolactin (complexed) fraction of total prolactin is <50%, the specimen is considered negative for macroprolactin. When total prolactin exceeds the upper reference limit and macroprolactin is negative, other causes for hyperprolactinemia should be explored.
When the percentage of the precipitated (complexed) prolactin fraction of total prolactin is > or =50%, the specimen is considered positive for the presence of macroprolactin.
Following macroprolactin precipitation, a patient whose unprecipitated prolactin level is greater than the upper limit of the total prolactin reference range may have hyperprolactinemia.
See PRL/8690 Prolactin, Serum for interpretation of prolactin levels.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Demonstration of the presence of macroprolactin does not exclude the possibility of concomitant presence of pituitary adenoma. Results should be interpreted in conjunction with clinical findings.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Fahie-Wilson M: In hyperprolactinemia, testing for macroprolactin is essential. Clin Chem 2003;49(9):1434-1436
2. Gibney J, Smith TP, McKenna TJ: Clinical relevance of macro-prolactin. Clin Endocrinol 2005;62:633-643
Method Description Describes how the test is performed and provides a method-specific reference
The instrument use for testing is the Roche Cobas 6000. An equal volume of 25% polyethylene glycol (PEG) is added to a serum prolactin sample causing the biologically inactive form of prolactin (macroprolactin) to precipitate. Following centrifugation, prolactin is measured in the supernatant (containing unprecipitated prolactin), as well as in an aliquot of the native sample. Precipitated prolactin is calculated by subtracting the unprecipitated prolactin value from the total prolactin. The percentage of precipitated prolactin to total prolactin indicated the presence or absence of macroprolactin. (Package insert: Elecsys and Modular Prolactin II, Roche 2005)
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.
84146 x 2
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|