Fibrinogen Activity, Clauss

Test Code

461

CPT Codes
85384

Preferred Specimen

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

Minimum Volume

0.5 mL

Other Acceptable Specimens

Minimum: 4.5 mL whole blood collected in a 3.2% sodium citrate (light blue-top) tube

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 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 vial

Transport Temperature

Plasma: Frozen
Whole blood: Room temperature

Specimen Stability

Plasma
Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 30 days
⁠⁠⁠⁠⁠⁠⁠
Whole blood
Room temperature: 24 hours
Refrigerated: 24 hours
Frozen: Unacceptable

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

Gross hemolysis • Clotted specimens

Methodology
Photometry/Optical, Clauss

Setup Schedule

Monday-Saturday Night
Report available: Next Day

Limitations

Expected impact by therapeutic levels (potential interference depends upon drug concentration): Warfarin: no effect; Heparin (UFH or LMWH): UFH-no effect, LMWH-normal to falsely low; Dabigatran or Argatroban (Thrombin Inhibitors): no effect or falsely low; Rivaroxaban or Apixaban (Factor Xa Inhibitors): no effect.

Reference Range

175-425 mg/dL

Clinical Significance

Fibrinogen is essential for the formation of a blood clot. Deficiency can produce mild to severe bleeding disorders.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

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.