Evaluation of two D-Dimer assays in the diagnosis of venous thromboembolism

A qualitative (Instantia®) and a quantitative (VIDAS D-Dimer®) D- Dimer test have been evaluated and compared with an ELISA method (Asserachrom D-D®) in a population of 74 patients suspected of presenting a deep vein thrombosis. Among the thirty-two patients presenting a deep vein thrombosis on phlebography, there were 16 (50%) proximal vein thrombosis and 16 (50%) distal vein thrombosis. Sensitivity and negative predictive value for proximal thrombosis were 100% in all three tests. For distal vein thrombosis, sensitivity and negative predictive value were respectively 8 1% and 8 1% for Asserachrom D-DI® 75% and 76% for VIDAS D-Dimer® and 63% and 82% for Instantia®. In conclusion, this study shows that these D-Di assays are a useful tool to exclude proximal vein thrombosis, at least for patients who are not under anticoagulant therapy.