Single or triple positivity for antiphospholipid antibodies in “carriers” or symptomatic patients: Untangling the knot

• Published in: Journal of thrombosis and haemostasis Vol. 19; no. 12; pp. 3018 - 3030
• Main Authors: Bertin, Daniel, Camoin‐Jau, Laurence, Veit, Véronique, Resseguier, Noémie, Lambert, Mathilde, Buffet Delmas, Pauline, Heim, Xavier, Mège, Jean‐Louis, Morange, Pierre‐Emmanuel, Bardin, Nathalie
• Format: Journal Article
• Language: English
• Published: England Elsevier Limited 01.12.2021; Wiley
• Subjects: Antibodies, Anticardiolipin; Antibodies, Antiphospholipid; Antiphospholipid antibodies; antiphospholipid syndrome; Antiphospholipid Syndrome - diagnosis; Antiphospholipid Syndrome - drug therapy; anti‐cardiolipin antibodies; Autoantibodies; Autoimmune diseases; Bacteriology; beta 2-Glycoprotein I; Cardiolipin; Cardiology and cardiovascular system; Diphosphatidylglycerol; Disease management; Emerging diseases; Glycoprotein I; Human health and pathology; Humans; Immunoglobulin G; Infectious diseases; Life Sciences; lupus anticoagulant; Lupus Coagulation Inhibitor; Microbiology and Parasitology; Parasitology; Patients; Phenotypes; Retrospective Studies; triple positive APL; Virology; antiphospholipid syndrome; anti-cardiolipin antibodies; lupus anticoagulant; triple positive APL; antiphospholipid antibodies
• ISSN: 1538-7933; 1538-7836; 1538-7836
• DOI: 10.1111/jth.15518

Background Although the triple positivity of antiphospholipid antibodies (aPL) is important for classifying high‐risk patients, interpretation of aPL positivity, namely the lupus anticoagulant (LA), anti‐cardiolipin (aCL), and anti‐beta2‐glycoprotein I autoantibodies (aB2GPI) remains challenging for thrombotic risk stratification. Objective To compare biological and clinical data between triple aPL– and single aCL–positive patients. Methods Of the 6500 patients assayed for aPL in daily practice within 3 years, we retrospectively analyzed data from 161 patients that were either triple aPL–positive or single aCL–positive with 5 years’ follow‐up for 121 of them. Results Whatever triple or single aPL positivity, we found a high prevalence of “carrier” patients (43%), which led us to question the clinical relevance of the triple aPL positivity. This result also justified the need to identify high‐risk profiles. In asymptomatic patients, high risk of thrombotic events is associated with (1) two positive tests for LA or a Rosner Index >27 combined with both aCL‐IgG and aB2GPI‐IgG positivity, (2) persistent single aCL positivity without an associated autoimmune disease. In symptomatic patients, we demonstrated differences in the phenotype of patients and their therapeutic anticoagulation according to the number of positive aPL but we did not find differences in the number of clinical events, recurrence, or relapse, even in the absence of treatment. Conclusion This study shows that the thrombotic risk does not necessarily increase with the number of positive tests and raises the question of the therapeutic management of single aCL–positive patients.