[4] Nonstandard abbreviations: RPL, recurrent pregnancy loss; APS, antiphospholipid syn drome; SLE, systemic lupus erythematosus; aPL, antiphospholipid antibody; LA, lupus anticoagulant; PT, prothrombin time; APTT, activated partial thromboplastin time;
DRVVT, dilute Russell's viper venom time; HELLP, hemolysis, increased liver enzymes, low platelets; EULAR, European League Against Rheumatism; LMWH, low-molecular weight heparin; HCQ, hydroxychloroquine.
As the
DRVVT was negative in our patient, did she really have lupus anticoagulant?
ABBREVIATIONS: APL = antiphospholipid antibodies; APS = antiphospholipid syndrome; APTT = activated partial thromboplastin time; [[beta].sub.2]-GPI = [beta.sub.2]-glycoprotein I;
dRVVT = dilute Russell's viper venom time; ELISA = enzyme-linked immunosorbent assay; Ig = immunoglobulin; KCT = kaolin clotting time; LA = lupus anticoagulant.
The relative responsiveness of aPTT,
dRVVT, and KCT for screening of LA-positive plasmas is shown in Fig.
[1] Nonstandard abbreviations: AT, anti thrombin; PC, protein C; PS, protein S; APC, activated protein C; FV, factor V; LA, lupus anticoagulant; C4bBP, C4b binding protein; APTT, activated partial thromboplastin time; aCL, anticardiolipin; KCT, kaolin clotting time; and
dRVVT, diluted Russell viper venom test.
Three (patients 19, 26, and 47) of the 14 patients were positive for LA with 2 tests (commercial
dRVVT and StaClot-LA).
Results of all 491 patients comparing the 2 methods of data analysis,
dRVVT and percentage correction.
Interestingly, this effect was not seen in
dRVVT confirmation testing.
His
DRVVT, which was normal at admission, was elevated at 11 months and 23 months, consistent with the presence of lupus anticoagulant; this normalized 3.5 years after admission.
[3] Nonstandard abbreviations: VKA, vitamin K antagonist; UFH, unfractionated heparin; LMWH, low molecular weight heparin; NOA, new oral anticoagulant; FXa, activated factor X; INR, international normalized ratio; rFVIIa, recombinant activated FVII; PT, prothrombin time; APTT, activated partial thromboplastin time;
dRVVT, dilute Russell viper venom test; TCT, thrombin clotting time; ECT, ecarin clotting time; [C.sub.max], peak NOA concentration in plasma; [C.sub.trough], nadir NOA concentration in plasma; [ISI.sub.VKA], international sensitivity index for VKA; APC, activated protein C; APC-R, APC resistance; LA, lupus anticoagulant.
"Study after study has shown that the dPT test is required to find lupus- anticoagulant patients that the other tests (e.g.,
dRVVT and lupus sensitive aPTT test) do not find.
LA was studied in two coagulation systems, a dilute sensitized activated partial thromboplastin time (aPTT) and a dilute Russell's viper venom time (
dRVVT), followed by confirm test, using reagents and instrumentation by Hemoliance Instrumentation Laboratory, Lexington, MA, USA.