Laboratory Test Reference Guide

Sample must be walked to the laboratory and within 4 hours of collect 

A discard tube (BD sodium citrate tube) must be taken prior to the Greiner tube

Normal individual not taking P2Y12                                                           180-376 PRU
Evidence of P2Y12 receptor blockade                                                     <180 PRU

Test results are reported in P2Y12 reaction units (PRU) which indicate the amount of ADP-mediated aggregation specific to the platelet P2Y12 receptor and is used to measure the effects of anti-platelets drugs specific to this receptor such as Clopidogrel.

The reference range for individuals NOT receiving a P2Y12 inhibitor is 180-376 PRU. PRU levels less than 180 are specific evidence of an anti-platelet effect due to P2Y12 receptor blockade.  Reference ranges are established in patients with acute coronary syndrome but evidence is lacking for neurovascular patients with TIA or stroke, neurosurgical settings, as well as for patients with peripheral artery disease treated conservatively or undergoing vascular surgery or angiological intervention. Optimal therapeutic and pre-surgical PRU targets have not been established.

Assay performance is affected by haematocrit values <0.33 or >0.52 and platelet counts <119X109/L or >502x109/L. Glycoprotein IIb/IIIa inhibitors abciximab, eptifibatide and tirofiban significantly affect platelet aggregation. 

% inhibition is not reported but can be manually calculated if a baseline sample is performed prior to commencing P2Y12 therapy. 

Percent inhibition = (Baseline PRU- Post- treatment PRU) / Baseline PRU x 100

Dr Helen Moore (Haematologist)

Verify Now Sample Testing Requirements