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HelpOrder Code LABDRVI1 Dilute Russell's Viper Venom Time (DRVVT), with Reflex, Plasma
Additional Codes
Mayo Test Code: DRVI1
Ordering Guidance
Because no single coagulation test can identify or exclude all lupus anticoagulants (LA), and because of the complexity of testing LA, one of the following Coagulation Consultation reflexive panel procedures are recommended if clinically indicated:
ALUPP / Lupus Anticoagulant Profile, Plasma
AATHR / Thrombophilia Profile, Plasma and Whole Blood
APROL / Prolonged Clot Time Profile, Plasma
Additional Testing Requirements
Serum anticardiolipin antibody testing (CLPMG / Phospholipid [Cardiolipin] Antibodies, IgG and IgM, Serum) and anti-beta-2 glycoprotein I (B2GMG / Beta-2 Glycoprotein 1 Antibodies, IgG and IgM, Serum) antibody testing should also be performed in conjunction with coagulation-based testing for lupus anticoagulants to enhance detection of different types of antiphospholipid antibodies.
Shipping Instructions
Send specimens in the same shipping container.
Specimen Required
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.
Additional Information:
1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Each coagulation assay requested should have its own vial.
Useful For
Detecting and confirming 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
Additional Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| DRVI4 | DRVVT Interpretation | No | Yes |
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| DRVI2 | DRVVT Mix Ratio | No | No |
| DRVI3 | DRVVT Confirmation Ratio | No | No |
Testing Algorithm
If dilute Russell's viper venom time (DRVVT) ratio is 1.20 or above, then DRVVT mix and DRVVT confirmation will be performed at an additional charge.
If DRVVT ratio is less than 1.20, the DRVVT mix and DRVVT confirmation will not be performed.
A DRVVT interpretation will always be performed.
Special Instructions
Method Name
Optical Clot-Based
Reporting Name
DRVVT Screen Ratio, w/Reflex, PSpecimen Type
Plasma Na CitSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Plasma Na Cit | Frozen | 14 days |
Reject Due To
| Gross hemolysis | Reject |
| Gross lipemia | Reject |
| Gross icterus | Reject |
Reference Values
Dilute Russell's viper venom time screen ratio: <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) screening assay is performed on the Instrumentation Laboratory ACL TOP. Patient plasma is incubated for a specified time, then combined with a DRVVT screening reagent containing Russell's viper venom, phospholipids, heparin neutralizing agents, calcium, buffers, and stabilizers to trigger the coagulation process. Subsequently, the time to clot formation is measured optically using a wavelength of 671 nm. The patient DRVVT screening clotting time is normalized by dividing the patient result by the mean DRVVT screening clotting time of normal pooled plasma to yield a ratio (DRVVT screen ratio).
Patient samples with a prolonged DRVVT (DRVVT screen ratio ≥1.20) are further studied by adding an equal volume of normal pooled plasma (platelet-depleted) and repeating the DRVVT test procedure, with mathematical normalization, to yield the DRVVT mix (1:1) ratio and the DRVVT test using DRVVT confirmatory reagent (enriched in phospholipid), and results are expressed as the quotient obtained from dividing the patient DRVVT screening clotting time by the patient DRVVT confirmatory clotting time (DRVVT confirm ratio).(Thiagarajan P, Pengo V, Shapiro SS. The use of the dilute Russell's viper venom time for the diagnosis of lupus anticoagulants. Blood.1986;68[4]:869-874; package insert: LA CHECK DRVVT. Precision BioLogic; 01/2023; package insert: LA SURE DRVVT. Precision BioLogic; 01/2023)
Day(s) Performed
Monday through Friday
Performing Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
85613
85613 (if appropriate)
85613 (if appropriate)
Forms
If not ordering electronically, complete, print, and send a Coagulation Test Request (T753) with the specimen.