Contribution of a new, rapid, individual and quantitative automated D-dimer ELISA to exclude pulmonary embolism.

The performance of a new automated ELISA for a rapid, individual and quantitative measurement of plasma D-dimer (VIDAS D-dimer) has been evaluated. First, a study of 100 patients was performed in order to choose the best couple of antibodies in comparison with an already clinically validated ELISA. Then the results were certified in a prospective study including 195 consecutive patients suspected of pulmonary embolism (PE). For a cut-off level of 500 ng/ml VIDAS D-dimer showed a sensitivity of 100% (95% confidence interval 92-100), a specificity of 37.6%, a negative predictive value of 100% (95% CI 93.3-100) and a positive predictive value of 33.1%. During a 6 months' follow-up no patient (95% CI 0-6.4) with D-dimer < 500 ng/ml presented a new suspicion of venous thromboembolic disease. These results suggest that this rapid and single-dose ELISA provides a very useful tool for the clinician to exclude on a day-to-day basis the diagnosis of PE.