Detection and quantitative evaluation of lupus circulating anticoagulant activity

Area of Science:

• Hematology
• Immunology
• Rheumatology

Background:

• Systemic lupus erythematosus (SLE) is associated with an increased risk of thrombotic events.
• Circulating anticoagulants, particularly lupus-type, are implicated in the pathophysiology of thrombosis in SLE.
• Accurate detection of these anticoagulants is vital for risk stratification and management.

Purpose of the Study:

• To investigate the prevalence of lupus-type circulating anticoagulant in SLE patients.
• To compare the sensitivity of various coagulation tests for anticoagulant detection.
• To explore the association between anticoagulant presence and clinical manifestations like thromboembolism and recurrent abortions.

Main Methods:

• Sixty-six SLE patients were assessed for lupus-type circulating anticoagulant.
• Multiple coagulation tests, including recalcification time, kaolin clotting time mixture test, tissue thromboplastin inhibition test, and activated partial thromboplastin time (APTT) with two reagents, were employed.
• A numerical index for anticoagulant presence and quantification was proposed.

Main Results:

• Circulating anticoagulant activity was detected in 49% of the studied SLE patients.
• Recalcification time demonstrated the highest sensitivity as a screening test.
• The kaolin clotting time mixture test proved most effective for confirming the anticoagulant's presence, while APTT showed significant false-negative rates (73% and 52%).

Conclusions:

• A significant proportion of SLE patients harbor lupus-type circulating anticoagulants.
• Recalcification time and kaolin clotting time mixture test are valuable tools for detecting and confirming this anticoagulant.
• The study highlights the correlation between anticoagulant activity and thromboembolic events/recurrent abortions in SLE.