Print View Attached Docs:
Alias Names: Lupus Anti-coagulation / LA Panel / LI Panel
Methodology: Mechanical clot detection
Edit Date: 6/11/2010
Components: Activated Partial Thromboplastin Time (APTT) / Russell Viper Venom Time (RVVT). Additional tests are added as needed, including: Activated Partial Thromboplastin Time (APTT) Mixing Study / Hexagonal Lipid Neutralization / Russell Viper Venom Time Neutralization.
Performed: Monday, Thursday
Released: 4 days
CPT Code: 85613 / 85730
Specimen Collection Details
Collection: Four 4.5 mL light blue top tubes (sodium citrate). Collect by careful venipuncture to avoid tissue fluid contamination or hemolysis. Do not use needles smaller than 23 gauge. Fill to maximum draw, at least 90% full. Mix by gentle inversion. When urgent testing is needed, call Special Coagulation Department, 541.687.2134 x4612, to assure STAT testing.
Handling: Due to short stability specimen must either be sent STAT to arrive in the laboratory within 4 hours, or sent frozen. For STAT, refrigerate and keep capped in original tubes. Call for STAT pick-up. For standard delivery, centrifuge to produce platelet-poor plasma (at least 1700 X G for 15 minutes to produce PLT CT less than 10,000 per cumm) and using a plastic pipette, transfer the top 2/3 of plasma into 3-4 plastic vials. Label with patient name, I.D. number, test, and “citrated plasma.” Freeze immediately. Send to laboratory within 7 days. If multiple tests are ordered, freeze a separate aliquot for this test. Note: It is very important the plasma be platelet-poor prior to freezing to prevent neutralization of the lupus inhibitor by platelet phospholipids. Platelet counts on platelet-poor plasma should be consistently below 10,000 per cumm. If not, centrifuge speed and/or spin time should be increased.
Stability: 4 hours ambient or refrigerated, or 14 days frozen.
Standard Volume: Four 4.5 mL light blue top tubes or 4 mL plasma.
Minimum Volume: Two 2.7 mL tubes or 2 mL plasma.
Transport: Original tubes refrigerated if STAT, or citrated plasma frozen on dry ice.
Comments: This test is designed to detect or exclude a lupus inhibitor (= lupus anti-coagulant). For more general evaluation of prolonged APTT, Coagulation Study, Prolonged APTT Evaluation (25670) is recommended. The Lupus Inhibitor panel DOES NOT include serologic studies (anti-cardiolipin and anti-beta 2 glycoprotein) which are also useful in evaluating anti-phospholipid syndrome (APS). For comprehensive APS evaluation following ISTH guidelines, Coagulation Study, Anti-phospholipid Panel (25620) is recommended.

Lupus inhibitors are antibodies against phospholipids, which are detectable by clotting assays. Testing is performed using a screening APTT and RVVT, with prolonged results evaluated further with more specific confirmatory procedures (Hex Lipid Neutralization and/or RVTT Lipid Neutralization). If significant prolongation of the APTT or RVVT is detected, at least 6 seconds above normal, a mixing study is also performed. A summary interpretation accompanies each report.

Rejection Criteria: Visible fibrin; moderate to marked hemolysis; specimen received in laboratory beyond stated stability.


PeaceHealth Laboratories