Light transmission aggregometry in the diagnosis of thrombocytopathy

Platelet function disorders (PFD) are a rare and heterogeneous group of hemorrhagic diathesis. Comprehensive diagnostics of impaired platelet function (PLT) — the so called thrombocytopathy — requires the use of special testing. The gold standard for measurement/diagnostics of platelet function disorders is light transmission aggregometry (LTA). A platelet agonist (ADP, arachidonic acid, collagen, ristocetin, epinephrine) is added at an appropriate concentration to the sample of platelet-rich plasma. The interaction with the agonist leads to platelet activation and subsequent platelet aggregation. Aggregate formation is accompanied by a corresponding increase in light transmission. This review presents the principle of the LTA method, and a discussion of the basic panel of platelet aggregation agonists. In addition, the strengths and limitations of the LTA method are characterized and the method is compared with other alternative methods of PFD diagnostics.