Strategies for the safe and effective exclusion and diagnosis of deep vein thrombosis by the sequential use of clinical score, D-dimer testing, and compression ultrasonography.
Patients with suspected deep vein thrombosis (DVT) are subjected to leg vein compression ultrasonography (CUS) that confirms DVT in only 20 to 30% of patients. A positive CUS is consistent with DVT irrespective of clinical score. The sequential use of a simple clinical score assessment, a rapid sensitive enzyme-linked immunosorbent assay (ELISA) D-dimer test and CUS to safely exclude DVT is promising. The clinical score is a validated clinical model of complaints, signs, and symptoms, on the basis of which a pretest clinical probability for DVT can be estimated as low, moderate, and high. The safe exclusion of DVT by a rapid sensitive D-dimer test in combination with clinical score or CUS necessitates a negative predictive value of more than 99%. The negative predictive value for DVT is determined by the sensitivity of the rapid ELISA D-dimer test and the prevalence of DVT in subgroups of outpatients with suspected DVT. The prevalence of DVT in outpatients with a low, moderate, and high clinical score varies widely from 3 to 10%, 15 to 30% and more than 70%, respectively. A negative rapid ELISA D-dimer and a low clinical score (prevalence DVT 3 to 5%) will have a very high negative predictive value of more than 99.5% to exclude DVT without the need of CUS testing. A negative ELISA D-dimer test and a first-negative CUS safely exclude DVT in patients with a moderate clinical score with a negative predictive value of more than 99.5%, therefore obviating the need to repeat CUS. The use of a rapid ELISA D-dimer testing in patients with a high clinical score is not recommended. A negative CUS, a low clinical score, and a positive ELISA D-dimer, even less than 1000 ng/mL exclude DVT with a nega tive predictive value of more than 99%. Patients with a negative CUS, but a positive ELISA D-dimer, and a moderate or high clinical score have a probability of DVT of 3 to 5% and 20 to 30%, respectively, and are thus candidates for repeated CUS testing. The proposed sequential use of the clinical score assessment, a rapid ELISA D-dimer test, and CUS will be the most cost-effective diagnostic strategy for DVT because of a significant reduction of CUS examinations and gain of time for the patient and physician in charge.
Michiels
J J
JJ
Clinical Hemostasis and Thrombosis, Department of Hematology, University Hospital Antwerp and the Goodheart Institute Center for Hemostasis, Thrombosis, and Vascular Pathology, Rotterdam, The Netherlands. postbus@goodheartcenter.demon.nl
Freyburger
G
G
van der Graaf
F
F
Janssen
M
M
Oortwijn
W
W
van Beek
E J
EJ
D000465:Algorithms; D000933:Antifibrinolytic Agents / Q000378:metabolism; D003937:Diagnosis, Differential; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism; D006801:Humans; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic; D014463:Ultrasonography; D020246:Venous Thrombosis / Q000175:diagnosis* / Q000000981:diagnostic imaging
D000933:Antifibrinolytic Agents; D005338:Fibrin Fibrinogen Degradation Products; D011933:Reagent Kits, Diagnostic; C036309:fibrin fragment D