CRYOcheck™ Hex LA qualitative test kit to aid in the detection of lupus anticoagulant (LA) by the application of hexagonal phase phospholipids

CRYOcheck Hex LA is for clinical laboratory use as a qualitative test kit intended to aid in the detection of lupus anticoagulants (LA) in 3.2% citrated human plasma by the application of hexagonal phase phospholipids.

CRYOcheck Hex LA should be used as an integrated test for lupus anticoagulant detection.
For in vitro diagnostic use.
Lupus anticoagulants (LA) are heterogeneous autoantibodies, mainly of the IgG and IgM type, which are directed against phospholipids (PL) or phospholipid-protein complexes involved in coagulation1. LA antibodies are detected in patients’ plasma by PL-dependent clotting assays.

There is a significant association between LA and increased risk of clinical complications such as thrombotic events and recurrent fetal loss. Medical diagnosis of LA is based on clinical symptoms and laboratory results.

There is no gold standard test for LA. Considering the complexity of mechanism and the heterogeneous nature of LA antibodies, application of different clotting tests that work based on different principles has been recommended5. LA prolongs clot formation of PL-dependent coagulation (LA screening) tests in vitro, such as LA-sensitive activated partial thromboplastin time (APTT) or dilute Russell’s Viper Venom Time (dRVVT) screen.

To confirm the presence of LA in a plasma sample, correction of a prolonged clot time by extra PL (an LA confirmatory test) needs to be performed by laboratories as well as ruling out other abnormalities, such as factor deficiency and heparin presence5. CRYOcheck Hex LA is an integrated (screen and confirm) silica-based APTT assay for qualitative LA detection. The presence of LA in a plasma sample is confirmed by the correction of the APTT clot time (CT) of the sample upon the addition of a reaction mixture containing hexagonal phase PL. CRYOcheck Hex LA incorporates a pooled normal plasma (mixing test) and a heparin neutralizer.