BioMedica Diagnostics

DVVtest® REF 810 REF 825 IVD

DVVtest® REF 810 REF 825 IVD

CE Marked, FDA 510(K)Cleared, Health Canada Registered
DVVtest® is a dilute Russell’s Viper Venom Time (dRVVT) test intended for the determination of Lupus Anticoagulants (LA) in human plasma. The assay is for in vitro diagnostic use. The identification of Lupus Anticoagulants (LA) in plasma is a diagnostic hallmark of the antiphospholipid syndrome (APS), an autoimmune disorder clinically characterized by arterial and venous thrombosis, recurrent spontaneous fetal loss, thrombocytopenia and neurological disorders. Lupus Anticoagulants are immunoglobulins of the IgG, IgM and IgA isotypes that prolong one or more of the in vitro phospholipiddependent coagulation tests: Activated partial thromboplastin time (aPTT), Dilute prothrombin time (dPT), Textarin time or dRVVT. LA autoantibodies are specifically directed against a variety of phospholipid binding proteins including β2-glycoprotein I (β2GPI), prothrombin, and annexin V which are complexed to various anionic phospholipids (e.g. cardiolipin, phosphatidylinositol and phosphatidylserine). The International Society for Thrombosis and Haemostasis, Scientific Subcommittee Criteria on Lupus Anticoagulants and Phospholipid-dependent Antibodies has recommended that LA be diagnosed using coagulation-based screening tests and a confirmatory test containing a high phospholipid concentration. DVVtest is the primary screening diagnostic test for LA with DVVconfirm serving as its companion high phospholipid-containing test to confirm the diagnosis of LA.

The DVVtest reagent contains Factor X activator isolated from Russell’s Viper Venom that directly activates Factor X to Factor Xa in the presence of phospholipids and calcium. Factor Xa activates prothrombin to thrombin, which converts fibrinogen to fibrin leading to detectable clot formation in plasma. This direct activation of Factor X bypasses the contact and intrinsic pathways in the coagulation cascade, thereby excluding interference from deficiencies of Factors VIII, IX, XI and XII, or their respective inhibitors. A positive DVVtest is indicated by a significant prolongation of the phospholipiddependent clotting time. If a patient is suspected to have LA, the DVVtest may also be performed on samples with a normal APTT as the formulation of the reagent increases the test’s sensitivity and specificity to LA.