Test Details
Methodology
ECLIA
Use
Prolactin should be considered for work-up of galactorrhea (inappropriate lactation). A pituitary function test useful in the detection of prolactin-secreting pituitary tumors (microadenomas, macroadenomas) with or without galactorrhea, with or without structural evidence of sellar enlargement. An adult female premenopausal patient having amenorrhea and galactorrhea is highly suspect of pituitary prolactinoma and is a candidate for radiologic evaluation of the pituitary as well as serum prolactin levels. Elevated prolactin may be associated with corpus luteum insufficiency or anovulation. Sequelae of hyperprolactinemia include amenorrhea, anovulation and decreased bone density.
Monomeric prolactin, the bioactive form of prolactin, is used to assess true hyperprolactinemia not due to the presence of macroprolactin, which is prolactin bound to immunoglobulins, and has been shown to have low biological activity in vivo. Presence of macroprolactin should be checked in the context of asymptomatic hyperprolactinemia.
Special Instructions
If prolactin tests above reference range, testing will reflex to macroprolactin, performed at an additional charge.
If the patient's date of birth (DOB) and/or sex was not provided, testing will reflex to macroprolactin, independent of prolactin results.
References
Specimen Requirements
Specimen
Serum (preferred) or plasma, frozen
Volume
2.0 mL
Minimum Volume
1.0 mL (Note: This volume does not allow for repeat testing.)
Container
Serum from a gel tube; serum from red-top tube; serum transfer tube; plasma transfer tube or plasma from green-top tube
Collection Instructions
Prolactin: If a red-top tube or plasma is used, transfer separated serum or plasma to a plastic transport tube.
Macroprolactin: Do not draw sample until patient has been awake for at least two hours. Separate serum or plasma from cells within 45 minutes of collection. Transfer specimen to plastic transport tube before freezing. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 14 days |
Refrigerated | 14 days |
Frozen | 6 months |
Freeze/thaw cycles | Stable x6 |
Storage Instructions
Freeze.
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 505990 | Prolactin Rfx Macroprolactin | 500325 | Prolactin | ng/mL | 2842-3 | |
| 505990 | Prolactin Rfx Macroprolactin | 505992 | Macroprolactin Reflex | N/A | ||
| Order Code | 505990 | |||||
| Order Code Name | Prolactin Rfx Macroprolactin | |||||
| Order Loinc | ||||||
| Result Code | 500325 | |||||
| Result Code Name | Prolactin | |||||
| UofM | ng/mL | |||||
| Result LOINC | 2842-3 | |||||
| Order Code | 505990 | |||||
| Order Code Name | Prolactin Rfx Macroprolactin | |||||
| Order Loinc | ||||||
| Result Code | 505992 | |||||
| Result Code Name | Macroprolactin Reflex | |||||
| UofM | ||||||
| Result LOINC | N/A |
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 500326 | Monomeric Prolactin | 500326 | Monomeric Prolactin | ng/mL | 42607-2 |
| Reflex 1 | ||||||
| Order Code | 500326 | |||||
| Order Name | Monomeric Prolactin | |||||
| Result Code | 500326 | |||||
| Result Name | Monomeric Prolactin | |||||
| UofM | ng/mL | |||||
| Result LOINC | 42607-2 | |||||
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 500327 | Percent Macroprolactin | 500327 | Percent Macroprolactin | % | 51441-4 |
| Reflex 1 | ||||||
| Order Code | 500327 | |||||
| Order Name | Percent Macroprolactin | |||||
| Result Code | 500327 | |||||
| Result Name | Percent Macroprolactin | |||||
| UofM | % | |||||
| Result LOINC | 51441-4 | |||||