Plasminogen activator inhibitor

Keywords: PAI

Description:

This assay is rarely performed and only in specialised laboratories.

Specimen:

4.5 mL blood added to 0.5 mL citrate.

Method:
  1. Functional assay: PAI activity measured by urokinase inhibition.

  2. Immunoassay.

Reference Interval:

Guide only.

Functional assay: 0-3.5 U/mL

Immunoassay: 4-43 ng/mL.

Application:

Rarely performed. Investigation of recurrent thrombotic episodes.

Interpretation:

PAI is an inhibitor of the fibrinolytic system.

Elevated levels may be found in acute myocardial infarction, malignancy, pre-eclampsia, infectious disease, and following surgery (trauma).

Reference:

Bain et al. Dacie and Lewis Practical Haematology. 11th Ed. 2012.