Sign in →

Order Code DRVI2 Dilute Russell's Viper Venom Time (DRVVT) Mix Ratio, Plasma


Specimen Required


Only orderable as part of a reflex. For more information see DRVI1 / Dilute Russell's Viper Venom Time (DRVVT), with Reflex, Plasma.

 

Specimen Type: Platelet-poor plasma

Collection Container/Tube: Light-blue top (3.2% sodium citrate)

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions:

1. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing.

2. Centrifuge, remove plasma, and centrifuge plasma again.

3. Aliquot into a separate plastic vial, leaving 0.25 mL in the bottom of the centrifuged vial.

4. Freeze plasma immediately (no longer than 4 hours after collection) at -20° C or, ideally, -40° C or below.


Useful For

Detecting the presence or helping to exclude the presence of lupus anticoagulants (LA)

 

Identifying LA that do not prolong the activated partial thromboplastin time (APTT)

 

Evaluating unexplained prolongation of the APTT or prothrombin time clotting tests

 

Distinguishing LA from a specific coagulation factor inhibitor or coagulation factor deficiencies

Method Name

Only orderable as part of a reflex. For more information see DRVI1 / Dilute Russell's Viper Venom Time (DRVVT), with Reflex, Plasma.

 

Optical Clot-Based

Reporting Name

DRVVT Mix Ratio

Specimen Type

Plasma Na Cit

Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Plasma Na Cit Frozen 14 days

Reference Values

Only orderable as part of a reflex. For more information see DRVI1 / Dilute Russell's Viper Venom Time (DRVVT), with Reflex, Plasma.

 

<1.20

Normal ranges for children: not clearly established, but similar to normal ranges for adults, except for newborn infants whose results may not reach adult values until 3 to 6 months of age.

Method Description

The dilute Russell's viper venom time (DRVVT) mix assay is performed on the Instrumentation Laboratory ACL TOP. Patient plasma is mixed in a 1:1 ratio with normal pooled plasma and incubated for a specified time, then combined with a DRVVT screening reagent containing Russell's viper venom, phospholipids, heparin neutralizing agents, calcium, buffers, stabilizers, and sodium azide to trigger the coagulation process. Subsequently, the time to clot formation is measured optically using a wavelength of 671 nm.

 

The patient DRVVT mix clotting time is normalized by dividing the patient result by the mean DRVVT screening clotting time of normal pooled plasma to yield a ratio.(Package insert: CRYOcheck LA Check. Precision BioLogic, Inc; 01/2023)

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

85613