A review of platelet function and testing

Platelet function testing is an area of recent growth and development in clinical laboratories. Additions to classical testing procedures include aggregation and retention tests and measurement of platelet release products. The necessity exists for understanding platelet structure and function. In this paper, the various platelet structures are demonstrated, their composition is described, and their individual contribution to platelet activation discussed. Platelet activation is described in four phases: adhesion, reversible contraction, aggregation, and release. Each is described in relationship to the others and laboratory test procedures marking each are described. The question of the relationship of measurement of platelet release markers to clinical condition is reviewed.