Assessing Plasmin Generation in Health and Disease.

Fibrinolysis is an important process in hemostasis responsible for dissolving the clot during wound healing. Plasmin is a central enzyme in this process via its capacity to cleave fibrin. The kinetics of plasmin generation (PG) and inhibition during fibrinolysis have been poorly understood until the recent development of assays to quantify these metrics. The assessment of plasmin kinetics allows for the identification of fibrinolytic dysfunction and better understanding of the relationships between abnormal fibrin dissolution and disease pathogenesis. Additionally, direct measurement of the inhibition of PG by antifibrinolytic medications, such as tranexamic acid, can be a useful tool to assess the risks and effectiveness of antifibrinolytic therapy in hemorrhagic diseases. This review provides an overview of available PG assays to directly measure the kinetics of plasmin formation and inhibition in human and mouse plasmas and focuses on their applications in defining the role of plasmin in diseases, including angioedema, hemophilia, rare bleeding disorders, COVID-19, or diet-induced obesity. Moreover, this review introduces the PG assay as a promising clinical and research method to monitor antifibrinolytic medications and screen for genetic or acquired fibrinolytic disorders.

Characterization of fibrin/fibrinogen degradation products reagents and their utility in critical care patients with enhanced fibrinolysis.

INTRODUCTION: Fibrin/fibrinogen degradation products (FDP) values reflect coagulation and fibrinolysis status, and FDP levels are helpful for diagnosis and classification of disseminated intravascular coagulation (DIC). FDP measurement has always played a key role in diagnosing DIC, a phenomenon that has recently gained renewed attention because of its occurrence in coronavirus disease 2019 (COVID-19) patients. Although the evaluation of FDP is crucial for the management of critical care, the variability among FDP reagents is unclear. In this study, we aimed to compare LIASAUTO P-FDP with three FDP reagents and investigate their characteristics. METHODS: In total, 172 plasmas samples were used in the correlation. The sample data were divided into three groups including negative, no and positive discrepancy based on the discrepancy percentages calculated from each correlation between LIASAUTO P-FDP and other three reagents. D-dimer, plasmin-α2 plasmin inhibitor complex (PIC), fibrin monomer complex (FMC), fibrinogen (Fbg) and Plasmin-α2 Plasmin Inhibitor (α2 PI) were measured and included in data analysis. RESULTS: The positive discrepancy groups showed higher D-dimer, PIC and FMC values than the negative discrepancy groups. The data indicated that LIASAUTO P-FDP had higher reactivity to D-dimer than other reagents and the values were elevated in the fibrinolysis-enhanced samples with various FDP fragments. CONCLUSION: LIASAUTO P-FDP displayed the reactivity towards various fibrin/fibrinogen degradation products, and it might be useful for DIC diagnosis because the fibrinolytic status differed in the DIC types and stages.