Widely Used Types and Clinical Applications of D-Dimer Assay

D-dimers are formed by the breakdown of fibrinogen and fibrin during fibrinolysis. D-dimer analysis is critical for the diagnosis of deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation. Modern assays for D-dimer are monoclonal antibody based. The enzyme-linked immunosorbent assay (ELISA) is the reference method for D-dimer analysis in the central clinical laboratory, but is time consuming to perform. Recently, a number of rapid, point-of-care D-dimer assays have been developed for acute care settings that utilize a variety of methodologies. In view of the diversity of D-dimer assays used in central laboratory and point-of-care settings, several caveats must be taken to assure the proper interpretation and clinical application of the results. These include consideration of preanalytical variables and interfering substances, as well as patient drug therapy and underlying disease. D-dimer assays should also be validated in clinical studies, have established cut-off values, and reported according to the reagent manufacturers recommendations. * Abbreviations : VTE : venous thromboembolism DVT : deep venous thrombosis PE : pulmonary embolism DDU : D-dimer unit FEU : fibrinogen-equivalent units CV : coefficient of variation FDPs : fibrinogen degradation products TPA : tissue plasminogen activator TAFI : thrombin-activatable fibrinolysis inhibitor DIC : disseminated intravascular coagulation TFR : time-resolved fluorometry CPR : clinical prediction rule CT : computed tomography ISTH : International Society of Thrombosis and Haemostasis