DIAGNOSTIC-VALUE OF A NEW SENSITIVE MEMBRANE-BASED TECHNIQUE FOR INSTANTANEOUS D-DIMER EVALUATION IN PATIENTS WITH CLINICALLY SUSPECTED DEEP VENOUS THROMBOSIS

Background: Plasma D-Dimer analysis, using ELISA assays, has demonstra ted in previous studies a high sensitivity, suggesting its utility in excluding deep venous thrombosis (DVT). Aim: To assess the performance of a new rapid plasma D-Dimer ELISA measurement in suspected DVT pati ents with recent clinical signs, not exceeding one week. Methods: A pr ospective study of patients admitted for a suspected recent DVT. Contr ast venography or compression ultrasonography were performed within 24 h of admission. A new membrane based ELISA technique, which uses an i mmunofiltration and two complementary monoclonal antibodies was tested . Results were expressed as positive or negative. A standard plasma D- Dimer ELISA measurement was also performed. D-Dimer performances were assessed at the end of the study. Results: 265/448 patients had a prov en DVT (72 distal, 193 proximal). The sensitivity of the instantaneous method in the diagnosis of overall DVT is 92 +/- 3.4% (95% CI), and s pecificity is 36.6 +/- 6.9%. Positive predictive value is 67.7 +/- 4.8 % and negative predictive value is 76.1 +/- 8.9%. Sensitivity and nega tive predictive values reach 97.9 and 94.3% in the diagnosis of proxim al DVT, but only 76.3 and 79.7% in the diagnosis of distal DVT. Simila r results are observed with the standard ELISA method. Conclusion: Thi s new rapid plasma D-Dimer measurement appears highly sensitive, and c ould substitute the older ELISA methods. Both methods provide lower se nsitivity in the case of a distal DVT location.