D-Dimer
Use
The Innovance® D-dimer assay is intended for use in conjunction with a nonhigh clinical pretest probability (PTP) assessment model to exclude deep vein thrombosis (DVT) and pulmonary embolism (PE).6 This test can be used to exclude VTE with nonhigh pretest probability (ie, low or low/moderate pretest probability). In an exclusion strategy, a D-dimer below the established threshold in a nonhigh pretest probability patient does not require further testing to exclude VTE.
Special Instructions
If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted. Refer to Coagulation Collection Procedures for directions. Patient samples may contain heterophilic antibodies (e.g., human anti-mouse antibodies [HAMA] and rheumatoid factors) that could react in immunoassays to yield falsely elevated results. This assay minimizes interference from heterophilic antibodies; however, complete elimination cannot be guaranteed.
Limitations
Results should be interpreted in conjunction with the patient's medical history, clinical presentation, and other findings. DVT clinical diagnosis should not be based solely on the Innovance® D-dimer result. D-dimer levels can be elevated due to a variety of clinical conditions, especially in hospitalized patients, and should not be used in pediatric patients for exclusion of venous thrombosis or pulmonary embolism. Several conditions like aortic aneurysm, trauma, surgery, disseminated malignancies, sepsis, and severe infections can increase D-dimer levels.
Methodology
Immunoassay (Immunoturbidimetric assay)
Biomarkers
LOINC Codes
- 48065-7
- 48065-7
Result Turnaround Time
1 day
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
2 mL
Minimum Volume
1 mL
Container
Blue-top (sodium citrate) tube
Collection Instructions
Citrated plasma samples should be collected by double centrifugation. Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion for proper blood to anticoagulant ratio. Mix immediately by gentle inversion at least six times. A discard tube is not required before collection. Centrifuge for 10 minutes and carefully remove 2/3 of the plasma, being careful not to disturb the cells. Deliver to a plastic transport tube, cap, and recentrifuge for 10 minutes. Transfer the plasma into a Labcorp PP transpak frozen purple tube with screw cap and freeze immediately.
Storage Instructions
Freeze.
Causes for Rejection
Gross hemolysis; clotted specimen; specimen thawed in transit; improper labeling
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | Unacceptable |
| Frozen | 4 weeks |