The quantitative immunoturbidimetric D-dimer method to rule out venous thromboembolism (VTE)

D-dimer measurement is a technique that may improve the diagnostic strategy for venous thrombo-embolism (VTE). To evaluate D-dimer accuracy in the diagnosis of VTE, we identified 116 patients at Charleston Area Medical Center in Charleston, W.Va., for whom D-dimer assay had been performed to screen for VTE. Forty-one had VTE diagnosis confirmed (VTE-Positive); and 75 were ruled out (VTE-Negative); all by radiologic studies. D-dimer values for 41 healthy individuals were also prospectively collected. D-dimer value ranges of VTE-Positive, VTE-Negative and Healthy Sample groups were 0.5-55, 0.5-15.9, and 0.4-3.24 mg/L. Cutoff values of 2.5, 2.1, 1.6, and 1 mg/L had sensitivities of 74%, 81%, 86% and 95%, with specificities of 60%, 48%, 32% and 12%, respectively. Negative predictive values were 80%, 81%, 79% and 82%, while positive predictive values were 52%, 48%, 43% and 39%, respectively. Our results show that quantitative D-dimer assays lack the accuracy to serve as a method for ruling out VTE.