D-dimer
In medicine, D-dimer is a fibrin degradation product after coagulation.
Immunologic tests for d-dimer are generally use immunoassays such as enzyme-linked immunosorbent assay or serologic tests such as agglutination tests. The immunoassays (more specifically, enzyme-linked immunosorbent assay) tend to be more sensitive.[1]
| sensitivity | specificity | |
|---|---|---|
| Immunoassays | ||
| Elisa such as VIDAS™ | 95%[1] 96%[2] |
44%[1] 39%[2] |
| Agglutination tests | ||
| Latex agglutination such as Tinaquant™ | 89%[1] 96%[2] |
45%[1] 43%[2] |
| Whole blood hemagglutination test such as SimpliRED™ | 78%[1] 87%[2] |
74%[1] 66%[2] |
Most patients with a pulmonary embolism have an abnormal alveolar-arterial oxygen gradient.[3]
Using D-dimer to determine duration of anticoagulation treatment
An abnormal D-dimer level at the end of treatment might signal the need for continued anticoagulation with warfarin among patients with embolism and thrombosis such as a first unprovoked pulmonary embolism. If the D-dimer is abnormal, anticoaguation should be continued, if the D-dimer is normal, the duration of treatment is uncertain.[4] In an observation study that collected the D-dimer before stopping anticoagulation, the D-dimer was not as predictive.[5]
Screening for deep venous thrombosis
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Stein PD, Hull RD, Patel KC, et al. (April 2004). "D-dimer for the exclusion of acute venous thrombosis and pulmonary embolism: a systematic review". Ann. Intern. Med. 140 (8): 589–602. PMID 15096330. [e]
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Di Nisio M, Squizzato A, Rutjes AW, Büller HR, Zwinderman AH, Bossuyt PM (February 2007). "Diagnostic accuracy of D-dimer test for exclusion of venous thromboembolism: a systematic review". J. Thromb. Haemost. 5 (2): 296–304. DOI:10.1111/j.1538-7836.2007.02328.x. PMID 17155963. Research Blogging.
- ↑ McFarlane MJ, Imperiale TF (1994). "Use of the alveolar-arterial oxygen gradient in the diagnosis of pulmonary embolism". Am. J. Med. 96 (1): 57–62. PMID 8304364. [e]
- ↑ Palareti G, Cosmi B, Legnani C, et al (2006). "D-dimer testing to determine the duration of anticoagulation therapy". N. Engl. J. Med. 355 (17): 1780-9. DOI:10.1056/NEJMoa054444. PMID 17065639. Research Blogging.
- ↑ Rodger MA, Kahn SR, Wells PS, Anderson DA, Chagnon I, Le Gal G, et al. Identifying unprovoked thromboembolism patients at low risk for recurrence who can discontinue anticoagulant therapy. CMAJ. 2008 Aug 26;179(5):417-426.