D-Dimer, Quantitative

Test Code

8659

CPT Codes
85379

Preferred Specimen

1 mL frozen platelet-poor plasma collected in 3.2% sodium citrate (light blue-top) tube

Minimum Volume

0.5 mL

Instructions

Please submit a separate, frozen vial for each special coagulation assay ordered.

Platelet poor plasma: Centrifuge light blue-top tube 15 minutes at approx. 1500 x g within 60 minutes of collection. Using a plastic pipette, remove plasma, taking care to avoid the WBC/platelet buffy layer and place into a plastic vial. Centrifuge a second time and transfer platelet-poor plasma into a new plastic vial. Plasma must be free of platelets (< 10,000/mcL). Freeze immediately and ship on dry ice.

Transport Container

Plastic screw-cap vial

Transport Temperature

Frozen (-70° C)

Specimen Stability

Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen (-70° C): 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Gross hemolysis • Gross lipemia • Clotted specimen • Improper blood to citrate ratio • Plasma received room temperature • Plasma received refrigerated

Methodology
Immunoturbidimetric

Setup Schedule

Set up: Tues-Sat evenings; Report available: Next day

Limitations

In patients with low or moderate probability of clots in the deep veins of the leg, a negative D-Dimer result generally rules out DVT. Some patients with blood clots will be false-negatives. This is most common among older patients, those who have undergone prolonged hospitalization, and those with markedly elevated C-reactive protein levels.

Reference Range

<0.50 mcg/mL FEU

Clinical Significance

D-Dimer is one of the measurable by-products of activation of the fibrinolytic system. Quantitation of D-Dimer assesses fibrinolytic activation and intravascular thrombosis. D-Dimer is of particular value in excluding the diagnosis of venous thromboembolism among patients at high risk.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.