Protocols for D-Dimer Measurements for Aid to Diagnosis or Exclusion of Venous Thromboembolism.

Measuring D-dimer is commonly used as a surrogate to indicate a clot-forming process, with subsequent lysis. This test has two primary intended uses: (1) as aid to diagnosis of various conditions and (2) venous thromboembolism (VTE) exclusion. If the manufacturer cites a VTE exclusion claim, the D-dimer test must only be used in evaluating patients with a non-high or unlikely pretest probability for pulmonary embolism and deep vein thrombosis. D-dimer kits with only aid to diagnosis claim should not be used for VTE exclusion. The intended use of the D-dimer may vary by region, and readership should consult manufacturer instructions for use to assure proper use of the assay. In this chapter, several methods for measuring D-dimer will be described.