A rapid quantitative D-dimer assay demonstrated 96% sensitivity (95% CI 75-100%) and a 98% negative predictive value for detecting deep vein thrombosis.
Observational (n=103)
Does a rapid quantitative D-dimer assay accurately diagnose deep vein thrombosis in patients with clinically suspected DVT or DVT recurrence?
A rapid quantitative D-dimer assay demonstrates high sensitivity and negative predictive value for DVT, suggesting it could safely reduce the need for compression ultrasonography and provide cost savings.
The sensitivity and specificity for deep vein thrombosis (DVT) of a new rapid, quantitative and precise (total imprecision or = 1.0 microgram/ml) for the presence of DVT was 96% (21/22 patients, 95% confidence interval 75-100%) with a specificity of 75% (64-84%), a negative predictive value of 98% (90-100%), a positive predictive value of 51% (35-67%), and an overall accuracy of 80% (70-87%). A normal D-dimer value (0.22 microgram/ml) was observed in one patient with DVT and symptoms lasting from 15 days. The approach of withholding C-US testing in patients with symptoms lasting from less than 11 days and D-dimer levels below the cut-off value was compared to serial C-US testing alone in a cost-effectiveness analysis subdividing the 66 patients with a first episode according to their clinical pretest probability of DVT. Thrombosis was detected in 6.7% of the patients in the low probability group (n = 15), 16.7% of the patients in the moderate probability group (n = 24), 51.9% of the patients in the high probability group (n = 27) and 8.1% of patients with suspected DVT recurrence. Calculated cost-savings for each DVT diagnosed ranged from 5% in the high pretest probability group to 55% in the low pretest probability group and to 77% in patients with suspected DVT recurrence. The safety of avoiding C-US testing in symptomatic patients with a negative D-dimer test should be evaluated in clinical management studies.
D’Angelo et al. (1996) conducted an observational in Clinically suspected deep vein thrombosis (DVT) (n=103). Rapid quantitative D-dimer assay (VIDAS D-DIMER) vs. Serial compression ultrasonography (C-US) was evaluated on Sensitivity of a positive D-dimer test (≥ 1.0 µg/ml) for the presence of DVT (95% CI 75-100). A rapid quantitative D-dimer assay demonstrated 96% sensitivity (95% CI 75-100%) and a 98% negative predictive value for detecting deep vein thrombosis.