Test Catalog

Test ID: DDITT    
D-Dimer, Plasma

Useful For Suggests clinical disorders or settings where the test may be helpful

Excluding the diagnosis of acute pulmonary embolism or deep vein thrombosis, particularly when results of a sensitive D-dimer assay are combined with clinical information, including pretest disease probability(1-4)


Diagnosis of intravascular coagulation and fibrinolysis, also known as disseminated intravascular coagulation, especially when combined with clinical information and other laboratory test data (eg, platelet count, assays of clottable fibrinogen and soluble fibrin monomer complex, and clotting time assays-prothrombin time and activated partial thromboplastin time)(5)

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

The specific degradation of fibrin (ie, fibrinolysis) is the reactive mechanism responding to the formation of fibrin. Plasmin is the fibrinolytic enzyme derived from inactive plasminogen. Plasminogen is converted into plasmin by plasminogen activators. The main plasminogen activators are tissue plasminogen activator (tPA) and pro-urokinase, which is activated into urokinase (UK) by, among others, the contact system of coagulation.


In the bloodstream, plasmin is rapidly and specifically neutralized by alpha-2-antiplasmin, thereby restricting its fibrinogenolytic activity and localizes the fibrinolysis on the fibrin clot. On the fibrin clot, plasmin degrades fibrin into various products (ie, D-dimers). Antibodies specific for these products, which do not recognize fibrinogen, have been developed. The presence of these various fibrin degradation products, among which D-dimer is the terminal product, is the proof that the fibrinolytic system is in action in response to coagulation activation.


Elevated D-dimer levels are found in association with disseminated intravascular coagulation (DIC), pulmonary embolism (PE), deep vein thrombosis (DVT), trauma, and bleeding. D-dimer may also be increased in association with pregnancy, liver disease, malignancy, inflammation, or a chronic hypercoagulable state.

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

< or =500 ng/mL Fibrinogen Equivalent Units (FEU)

D-dimer values < or =500 ng/mL FEU may be used in conjunction with clinical pretest probability to exclude deep vein thrombosis (DVT) and pulmonary embolism (PE).

Interpretation Provides information to assist in interpretation of the test results

A normal D-dimer result of 500 ng/mL or less fibrinogen equivalent units (FEU) on the IL D-Dimer HS500 kit has a negative predictive value of approximately 100% (range 97%-100%) and is FDA approved for the exclusion of acute pulmonary embolism (PE) and deep vein thrombosis (DVT) when there is low or moderate pretest probability for PE or DVT.


D-dimer concentrations increase with age and, therefore, the specificity for DVT and PE exclusion decreases with age. For DVT or PE exclusion, in addition to clinical pretest probability, age-adjusted D-dimer cutoffs are suggested for patients older than 50 years of age.


Recent evidence suggests using clinical pretest probability and age-adjusted cutoffs to improve the performance of D-dimer testing in patients older than 50 years of age. In recent studies, when compared to a fixed D-dimer cutoff, age-adjusted D-dimer cutoff values (calculated as follows: age [years] x 10 ng/mL) resulted in equivalent outcomes and no additional false negative findings.(6-7)


Increased D-dimer values are abnormal but do not indicate a specific disease state. D-dimer values may be increased as a result of:

-Clinical or subclinical disseminated intravascular coagulation/intravascular coagulation and fibrinolysis

-Other conditions associated with increased activation of the procoagulant and fibrinolytic mechanisms such as recent surgery, active or recent bleeding, hematomas, trauma, or thromboembolism

-Association with pregnancy, liver disease, inflammation, malignancy, or hypercoagulable (procoagulant) states


The degree of D-dimer increase does not definitely correlate with the clinical severity of associated disease states.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

D-dimer results on the ACL TOP coagulation analyzer are not affected by rheumatoid factor up to 1400 IU/mL.


The monoclonal antibody (MA-8D3) used in the latex reagent has major specificity for the D-dimer domain of cross-linked fibrin degradation products (FDP). A low cross-reactivity to FDP was seen with plasma samples spiked with purified fragments D and E above 10 mcg/mL.


Specimens from patients who have received preparation of mouse monoclonal antibody for diagnosis or therapy may contain human antimouse antibody (HAMA). The presence of HAMA may cause an overestimation of results in immunoassays that utilize mouse monoclonal antibodies. The reaction buffer contains a blocking agent against HAMA to minimize this interference on the assay results.

Clinical Reference Recommendations for in-depth reading of a clinical nature

1. Brill-Edward P, Lee A: D-dimer testing in the diagnosis of acute venous thromboembolism. Thromb Haemost. 1999 August;82(2):688-694

2. Heit JA, Minor TA, Andrews JC, Larson DR, Li H, Nichols WL: Determinants of plasma fibrin D-dimer sensitivity for acute pulmonary embolism as defined by pulmonary angiography. Arch Pathol Lab Med. 1999 March;123(3):235-240. doi: 10.1043/0003-9985(1999)123.

3. Heit JA, Meyers BJ, Plumhoff EA, Larson DR, Nichols WL: Operating characteristics of automated latex immunoassay tests in the diagnosis of angiographically-defined acute pulmonary embolism. Thromb Haemost. 2000 June;83(6):970

4. Bates SM, Grand'Maison A, Johnston M, Naguit I, Kovacs MJ, Ginsberg JS: A latex D-dimer reliably excludes venous thromboembolism. Arch Intern Med. 2001 February;161(3):447-453. doi: 10.1001/archinte.161.3.447.

5. Levi M, Ten Cate H: Disseminated intravascular coagulation. N Engl J Med. 1999 Aug 19;341(8):586-592. doi: 10.1056/NEJM199908193410807.

6. Righini M, Van Es J, Den Exter PL, et al: Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study. JAMA. 2014 Mar 19;311(11):1117-1124. doi:10.1001/jama.2014.2135

7. Schouten HJ, Geersing GJ, Koek HL, et al: Diagnostic accuracy of conventional or age adjusted D-dimer cut-off values in older patients with suspected venous thromboembolism: systematic review and meta-analysis. BMJ. 2012;346:f2492. doi: 10.1136/bmj.f2492.

8. Feinstein DI, Marder VJ, Colman RW: Consumptive thrombohemorrhagic disorders. In: Colman RW, Hirsh J, Marder VJ, et al. eds. Hemostasis and Thrombosis: Basic Principles and Clinical Practice. 3rd ed. JB Lippincott Co.; 2001;1197-1234