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Prolactin
| Item | Value | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Approval req'd? | No | ||||||||
| Available Stat? | No | ||||||||
| Test code | PROL | ||||||||
| Test group | Prolactin | ||||||||
| Performed by | China Basin Chemistry | ||||||||
| In House Availability | Thursday, Sunday (day shift) | ||||||||
| Method | Chemiluminescent immunoassay (Centaur) | ||||||||
| Collection Instructions | Because of circadian changes in prolactin secretion, with peaks at night and in the afternoon, specimens should be drawn at the same time of day for comparability, preferably after fasting overnight. Medi-Cal Medical Necessity Policy (Medical Services Bulletin 307, Feb. 2000) applies. |
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| Container type | Gold top or Red top | ||||||||
| Amount to Collect | 2 mL blood | ||||||||
| Sample type | Serum | ||||||||
| Preferred volume | 1 mL serum | ||||||||
| Min. Volume | 0.2 mL serum | ||||||||
| Processing notes | Refrigerate | ||||||||
| Units | µg/L | ||||||||
| Normal range |
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| Turn around times | 1-3 days | ||||||||
| Additional information | Levels in newborns are > 10x those in adults. Levels in menstruating or post-menopausal women do not differ greatly from random levels in females. Note-Prolactin immunoassays vary in sensitivity to the presence of macroprolactin (Reference 1). Macroprolactin, a high molecular weight aggregate of monomeric prolactin and immunoglobulin, is estimated to be present in 5-25% of hyperprolactinemic patients (Reference 1, 2). Although the precise biologic role of macroprolactin remains unclear, patients with hyperprolactinemia due to macroprolactin often respond to treatment with dopamine agonists (Reference 2). Clinicians should be aware that there may be inter-laboratory variation in reported values of prolactin due to the different sensitivities of commercial immunoassays to the presence of macroprolactin. The prolactin assay used at UCSF (Centaur) shows less reactivity with macroprolactin than several other assays (1). Assay for macroprolactin using the PEG precipitation procedure is available by sendout of 0.4 ml of serum to Quest. Adult male and female reference ranges were adopted from the manufacturer, Siemens Centaur reagent insert and verified by running adult male and female donor samples obtained from the UCSF Donor Center (excluding autologous donors). This assay standardization is traceable to World Health Organization (WHO) 3rd IRP for human Prolactin (84/500). References: 1. Smith TP, Suliman AM, Fahie-Wilson MN, McKenna TJ. Gross variability in the detection of prolactin in sera containing big big prolactin (macroprolactin) by commercial immunoassays. J Clin Endocrinol Metab. 2002 Dec;87(12):5410-5. 2. Olukoga AO, Kane JW. Macroprolactinaemia: validation and application of the polyethylene glycol precipitation test and clinical characterization of the condition. Clin Endocrinol (Oxf). 1999 Jul;51(1):119-26. Assay for macroprolactin using the PEG precipitation procedure is available by sendout of 0.2 ml of serum to Esoterix Laboratories |
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| LOINC code | 2842-3 | ||||||||
| Last Updated | 9/15/2011 3:18:37 PM | ||||||||
| Entry Number | 783 | ||||||||
| Lab Procedure Link | Click here for Procedure |
If you have additional questions regarding this test, please call: 415-353-1667