Plasminogen Activator Inhibitor 1 (PAI-1) Antigen
Also known as: PAI-1 Antigen
Use
Measure the quantity of PAI-1 in plasma, which may be useful in the determination of PAI-1 deficiency.6
Special Instructions
PAI-1 is an acute phase reactant with diurnal variations, and levels are usually highest in the morning. Significant elevations in PAI-1 are seen during the third trimester of pregnancy, especially in preëclamptic pregnancies. To avoid diurnal variation, specimens should be collected in the morning from patients in a resting state.
Limitations
Samples containing platelets before freezing can show erroneously high results due to latent PAI-1 release. The assay measures active, inactive (latent), and complexed forms of PAI-1, which could complicate interpretation. Hemolysis, clotted specimens, or instances where the specimen is contaminated with heparin or other anticoagulants are common causes for rejection. The correct ratio of blood to anticoagulant in the collection tube is crucial for accurate results.
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 22758-7
- 22758-7
Result Turnaround Time
4-8 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
0.5 mL
Minimum Volume
Not provided
Container
Blue-top (sodium citrate) tube
Collection Instructions
Citrated plasma samples should be collected by double centrifugation. Platelet-poor plasma is needed. Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Mix by gentle inversion at least six times. Centrifuge for 10 minutes and carefully remove 2/3 of the plasma, recenter the sample and remove plasma, avoiding platelet layer. Transfer to Labcorp PP transpak frozen purple tube with screw cap. Freeze immediately and maintain until tested.
Patient Preparation
The patient should be in a resting state, and the specimen collected in the morning to avoid diurnal variation of results.
Storage Instructions
Freeze.
Causes for Rejection
Hemolysis; clotted specimen; specimen contaminated with heparin; specimens containing fibrin clots; specimen thawed