Sign in →

Test Code LAB3210 Lupus Anticoagulant Panel with Reflexes

Performing Laboratory

Barnes-Jewish Hospital Laboratory

Methodology

Absorbance measurement, clot signature formation

Testing Algorithm:

If either Screening test is abnormal, then the DRVVT 50:50 mix, DRVVT confirmation, SCT 50:50 mix, and/or SCT confirmation may be performed at an additional charge.

Literature References:

1. Eby C. Antiphospholipid syndrome review. Clin Lab Med 2009;Jun;29(2):305-19.
2. Pengo V, et al. Update of the guidelines for lupus anticoagulant detection. Subcommittee on Lupus Anticoagulant/Antiphospholipid Antibody of the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis. J Thromb Haemost 2009;Oct;7(10):1737-40.

Specimen Requirements

Specimen Type: Plasma

Container/Tube: Light-blue top (citrate)

Specimen Volume: 2 Full tubes

Specimen Minimum Volume: 2 Full tubes

Collection Instructions:

  1. Draw a discard blue top tube prior to drawing a light-blue top (citrated) tube if using a Winged Infusion Set.  Discard tube should be under filled and discarded.
  2. Clotted blood or an insufficient specimen is not acceptable.
  3. Avoid phlebotomy techniques which cause hemolysis and heparin contamination.
  4. Follow nursing policy on volume of blood to discard prior to collecting blood from indwelling heparinized catheters.

Analyte Stability:

4 hours at 18° C to 24° C

Platelet-free plasma can be frozen at -20 for transport on dry ice up to 72 hours
or stored 6 months at -70° C.


Additional Information: If the patient is a hospital patient and the hematocrit is >55%, call Barnes-Jewish Hematology Laboratory at 314-362-5203 for instructions.

Day(s) Test Set Up

Monday, Wednesday, Friday

Cut-off time: 0800
Turnaround Time:
STAT: not available
Routine: results available the day of testing

Test Classification and CPT Coding

85670 – Thrombin Time
85613 – Russell viper venom time, diluted, screen
85732 - Silica clotting time, screen
If appropriate:
85613 – Russell viper venom time, diluted, 50:50 mix
85613 -  Russell viper venom time, diluted, confirmation
85732 - Silica clotting time, 50:50 mix

85732 - Silica clotting time, confirmation

 

Reference Values

Normal= dRVVT Screen ratio </= 1.20, Silica Clotting Time (SCT) ratio </= 1.16

 

Additional test as appropriate:

dRVVT Confirm ratio = </= 1.20

dRVVT Screen/Confirm ratio = Normal = </= 1.20

dRVVT 50:50 ratio, Normal = </= 1.20

SCT Confirm ratio = </= 1.16

SCT Screen/Confirm ratio = Normal = </= 1.16

SCT 50:50 ratio, Normal = </= 1.16

Literature Reference:

1. Eby C. Antiphospholipid syndrome review. Clin Lab Med 2009;Jun;29(2):305-19.
2. Giannakopoulos B, Passam F, Loannau Y, Krilis SA. How we diagnose the antiphospholipid syndrome. Blood 2009;Jan 29;113(5):985-94.

Specimen Transport Temperature

Ambient Yes/Refrigerate NO/Frozen Yes

Additional Information

For BJH Laboratory Use Only
Analyte Stability:

4 hours at 18° C to 24° C

Platelet-free plasma can be frozen at -20 for transport on dry ice up to 72 hours
or stored 6 months at -70° C.

Laboratory Processing Instructions:

Test performed in BJH Core Lab.

LOINC Code Information

Name LOINC Code
DRVVT 50/50 Ratio 75513-2
DRVVT Confirmation/Screen Ratio 50410-0
Interpretation 75514-0
SCT screen/confirmation ratio 66736-0
Thrombin Time 3243-3