[Detection of lupus anticoagulant using a modified diluted Russell's viper venom time test]

Area of Science:

• Hematology
• Immunology

Background:

• Lupus anticoagulants (LA) are linked to thrombosis and recurrent miscarriages.
• Diluted Russell's Viper Venom time (dRVVT) tests are used for LA detection.
• LA detection is crucial for managing patients at risk of clotting disorders.

Purpose of the Study:

• To evaluate a new simplified dRVVT test combining LUPO-TESTII and LUCOR for LA detection.
• To determine the diagnostic performance of the LUPO-TESTII/LUCOR ratio for LA.
• To compare the new test with existing methods like the platelet neutralization procedure test.

Main Methods:

• A simplified dRVVT test using LUPO-TESTII and LUCOR was evaluated.
• Receiver-operating characteristic (ROC) analysis was used to determine the optimal cut-off ratio.
• The LUPO-TESTII/LUCOR ratio was compared between LA-positive patients and control groups.

Main Results:

• The ratio of LUPO-TESTII/LUCOR values effectively detects LA, with a sensitivity of 92.3% and specificity of 96.8% at a cut-off of 1.07.
• LA-positive patients showed significantly higher ratios compared to warfarin-treated patients, those with clotting-factor deficiency, and those with specific clotting-factor inhibitors.
• The test results were not affected by warfarin, heparin treatment, or the presence of specific clotting-factor inhibitors.

Conclusions:

• The LUPO-TESTII/LUCOR ratio is a reliable indicator for detecting lupus anticoagulants.
• This simplified dRVVT test offers high sensitivity and specificity for LA diagnosis.
• The LUPO-TESTII/LUCOR ratio is a more useful indicator for LA detection than the platelet neutralization procedure test.