Lupus Anticoagulant with Reflex*

SIM

LAB2305

CPT

85613; 85732

Synonyms

Lupus Ag; Lupus Anticoagulant screen; Lupus Anticoagulant with reflex 

Specimen Type

Plasma, frozen

Container

Blue-top (sodium citrate) tube

Collection Instructions

Blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio. Sample should be mixed by gentle inversion at least six times to ensure adequate mixing.

Volume

Volume: 2 mL
Min. volume: 1 mL (this does not allow for repeat testing) 

Additional Information

Lupus anticoagulants are nonspecific antibodies that extend the clotting time of phospholipid-dependent clotting assays such as the aPTT. Unlike specific factor antibodies, LA are usually associated with venous thrombosis. 
This is not the Lupus with Cardiolipin.

Patient Preparation

Ideally, the patient should not be on anticoagulant therapy. Avoid warfarin (Coumadin®) therapy for two weeks prior to the test and heparin, direct Xa, and thrombin inhibitor therapies for about three days prior to testing.

Specimen Processing Instructions

Citrated plasma samples should be collected by double centrifugation.

Transport Requirements

Frozen only

Specimen Stability

7 days 

Rejection Criteria

Severe hemolysis; improper labeling; clotted specimen; specimen diluted with IV fluids; samples thawed in transit; improper sample type; sample out of stability

Reference Range

Reference range accompanies report

Critical Value

Test Includes

The qualitative detection of lupus anticoagulants in plasma 

Methodology

PTT-LA(lupus-sensitive aPTT) and drVVT screen; mixing study if screening tests are prolonged; confirmation if the mixing studies do not correct. 

Testing Frequency

LCA

117892 

Reviewed By

Rhonda Crowe    

Reviewed Date

2/27/23

Supplemental

*  Denotes Reference Lab Test