title: Comparison of the clinical usefulness of two quantitative D-Dimer tests in patients with a low clinical probability of pulmonary embolism.
abstract: BACKGROUND
  Quantitative D-Dimer tests are established methods in the non-invasive diagnostic management to rule out venous thromboembolism (VTE). The diagnostic performance and the clinical efficiency different D-Dimer assays in the exclusion of pulmonary embolism (PE) have not yet been compared in a clinical outcome study.
  
  
  OBJECTIVE
  Evaluation of the efficiency and safety of excluding the diagnosis of PE with two different quantitative D-Dimer assays in consecutive patients with clinically suspected PE.
  
  
  METHODS
  We studied the VTE-failure rate of 2206 consecutive patients with an unlikely clinical probability in whom VIDAS or Tinaquant D-Dimer tests were performed.
  
  
  RESULTS
  The prevalence of PE in 1238 patients whose D-Dimer level was analyzed with Tinaquant assay was 11%. The VIDAS assay group consisted of 968 patients with a PE prevalence of 13%. The VIDAS assay had a sensitivity of 99.2% (95%CI; 96- >99.9%), the Tinaquant assay of 97.3% (95%CI; 93 -99%). The negative predictive value (NPV) in the Tinaquant assay group was 99.4% (95%CI 98-99.8%) in comparison to 99.7% (95%CI 99->99.9%) in the VIDAS assay group. During 3 month of follow-up, there were no fatal cases of PE among patients with normal D-Dimer and unlikely clinical probability in both D-Dimer assay groups. In addition, the test efficiency of Tinaquant assay was significantly higher in comparison to VIDAS assay (52% vs 42%, p<0.001).
  
  
  CONCLUSIONS
  Both Tinaquant and VIDAS D-Dimer tests perform equally well in combination with an unlikely clinical probability in excluding PE. The Tinaquant test was shown to be more efficient.
authors.affiliation: Section of Vascular Medicine, Department of General Internal Medicine - Endocrinology, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: R Karami
authors.initials: RK
authors.lastname: Djurabi
authors.forename: F A
authors.initials: FA
authors.lastname: Klok
authors.forename: M
authors.initials: M
authors.lastname: Nijkeuter
authors.forename: K
authors.initials: K
authors.lastname: Kaasjager
authors.forename: P W
authors.initials: PW
authors.lastname: Kamphuisen
authors.forename: M H H
authors.initials: MH
authors.lastname: Kramer
authors.forename: M J H A
authors.initials: MJ
authors.lastname: Kruip
authors.forename: F W G
authors.initials: FW
authors.lastname: Leebeek
authors.forename: Harry R
authors.initials: HR
authors.lastname: Büller
authors.forename: M V
authors.initials: MV
authors.lastname: Huisman
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011336:Probability; D011655:Pulmonary Embolism / Q000097:blood / Q000175:diagnosis*
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D