[Value of combined wells score and D-dimer test on diagnosing patients with deep venous thrombosis]

To evaluate the value of Wells score or/and D-dimer test on diagnosing or excluding deep venous thrombosis (DVT).

Patients with suspected DVT were retrospectively analyzed. All patients underwent clinical assessment, D-dimer assay and bilateral lower extremity compression sonography within 48 hours of admission. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for diagnosing DVT by Wells score, D-dimer test, and combined Wells score and D-dimer were compared.

A total of 274 patients were analyzed. If low probability was defined as negative and moderate and high probabilities were defined as positive, the sensitivity, specificity, PPV and NPV of the Wells score were 78.4%, 66.1%, 52.3% and 86.6%, respectively. At a cut-off of 500 microg/L, the sensitivity, specificity, PPV and NPV of D-dimer test were 73.9%, 66.1%, 50.8% and 84.2%, respectively. If low probability and D-dimer < 500 microg/L were defined as negative, moderate and high probabilities and D-dimer > or = 500 microg/L were defined as positive, the sensitivity, specificity, PPV and NPV of the combined Wells score and D-dimer test were 88.3%, 76.8%, 67.1% and 92.5%, respectively.

For clinical suspected DVT patients, DVT diagnosis could be reliably obtained by combined Wells score and D-dimer test.