The performance of two rapid quantitative D-dimer assays in 287 patients with clinically suspected pulmonary embolism.
BACKGROUND
Objective tests are necessary for the diagnosis of pulmonary embolism (PE). D-dimer assays have been suggested as useful screening tests to exclude this diagnosis.


OBJECTIVE
To compare the diagnostic accuracy of two rapid quantitative D-dimers in patients with suspected pulmonary embolism.


METHODS
Plasma D-dimer levels were measured using two commercially available assays (Tinaquant and Vidas). A strict imaging protocol was used to arrive at a final diagnosis of PE or deep venous thrombosis (DVT).


METHODS
Multicenter study in six Dutch referral centers.


METHODS
A total of 287 in- and outpatients with clinically suspected pulmonary embolism.


METHODS
Diagnostic accuracy indices for the two assays were calculated and additional receiver-operated characteristics (ROC) analysis was performed.


RESULTS
Using the manufacturer's advised cutoff values, the sensitivity and specificity were 88% and 52% for Vidas and 82% and 61% for Tinaquant, respectively. These differences were statistically significant (McNemar, P < 0.0001). However, no statistical differences were found between the two assays using ROC analysis (AUC = 0.78 for both assays).


CONCLUSIONS
Both quantitative D-dimer tests had similar diagnostic accuracy; however, at the manufacturer's advised cutoff level, Vidas performed significantly better. Nevertheless, to safely exclude pulmonary embolism, D-dimer assays should be combined with other diagnostic tests.
de Monyé
Wouter
W
Department of General Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands. w.de_monye@lumc.nl
Sanson
Bernd-Jan
BJ
Büller
Harry R
HR
Pattynama
Peter M T
PM
Huisman
Menno V
MV
D000328:Adult; D016009:Chi-Square Distribution; D019281:Dimerization; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands; D011655:Pulmonary Embolism / Q000175:diagnosis*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013997:Time Factors