Platelet Phenotyping and Function Testing in Thrombocytopenia

Abstract

Patients who suffer from inherited or acquired thrombocytopenia can be also affected by platelet function defects, which potentially increase the risk of severe and life-threatening bleeding complications. A plethora of tests and assays for platelet phenotyping and function analysis are available, which are, in part, feasible in clinical practice due to adequate point-of-care qualities. However, most of them are time-consuming, require experienced and skilled personnel for platelet handling and processing, and are therefore well-established only in specialized laboratories. This review summarizes major indications, methods/assays for platelet phenotyping, and in vitro function testing in blood samples with reduced platelet count in relation to their clinical practicability. In addition, the diagnostic significance, difficulties, and challenges of selected tests to evaluate the hemostatic capacity and specific defects of platelets with reduced number are addressed.

Age-Dependent Control of Collagen-Dependent Platelet Responses by Thrombospondin-1—Comparative Analysis of Platelets from Neonates, Children, Adolescents, and Adults

“…(4) Platelet-platelet contact is not required as functional parameters are monitored on a single platelet. This enables platelet function analysis in thrombocytopenic samples, such as immune thrombocytopenia and combined platelet function and number disorders [ 52 ]. Our data clearly demonstrate that age-dependent changes of platelet reactivity and the achievement of adult platelet function depend on the agonist used and the platelet activation parameter.…”

Cell Attachment Capacity and Compounds of Fibrin Membranes Isolated from Fresh Frozen Plasma and Cryoprecipitate

“…Although plasma isolated by plasmapheresis is theoretically free from cellular elements, a small amount of platelets, leukocytes, and red blood cells were found in some of our samples. In control samples, approximately 10 × 10 9 /L platelets were measured compared to manually isolated PPP (platelet-poor plasma), which contains 34.5 × 10 9 /L [ 27 ]; however, the platelet count in plasma highly depends on the isolation method, and the normal platelet count of whole blood is 150–450 × 10 9 /L [ 28 ].…”

Special Issue: “The Latest Clinical Advances in Thrombocytopenia”

“…We observe that a number of these papers are already viewed at a high rate and even cited, supporting the value of this article series. For this issue, we acquired one original research article [1] and 13 reviews [2][3][4][5][6][7][8][9][10][11][12][13][14] that are shortly introduced below.…”

“…It is demonstrated that a low or high potential to generate procoagulant platelets in vitro may be associated with bleeding or thrombotic tendencies, respectively. A short summary of the thrombocytopathy associated with COVID-19 is added (for a discussion of platelet function testing, specifically in thrombocytopenic patients, see also the review by Jurk and Shiravand [11] introduced below).…”

“…Jurk and Shiravand share their expertise on platelet phenotyping and function testing in thrombocytopenic patients [11]. Patients with inherited or acquired thrombocytopenia may additionally display functional platelet defects, contributing to the bleeding risk.…”