Assessment of Platelet Function by Automated Light Transmission Aggregometry

Light transmission aggregometry (LTA) has long been the historical "gold standard" of platelet function testing and is typically performed in specialized hemostasis laboratories due to its manual and labor intensive process. However, newer automated testing provides a means of standardization and ability to perform the testing in routine laboratories. Here we describe the measurement of platelet aggregation in the CS-Series^™ (Sysmex Corporation, Kobe, Japan) and CN-Series™ (Sysmex Corporation, Kobe, Japan) routine blood coagulation analyzers. Differences in the methods for both analyzers are further described. For the CS-5100^™ analyzer, the final diluted concentrations of the agonists are prepared by manual pipetting from reconstituted agonist solutions. These prepared dilutions are eight times concentrated with respect to the final working concentration of the agonists and appropriately diluted within the analyzer to achieve the desired concentration of agonists prior to testing. For the CN-6000^™ analyzer, the dilutions of agonists and the final working concentrations are automatically prepared by the auto-dilution feature in the analyzer.