Profiling of non-criteria antiphospholipid antibodies in patients with SLE: differentiation of thrombotic SLE patients and risk of recurrence of thrombosis

Abstract

To reveal the clinical significance of criteria and non-criteria antiphospholipid antibodies detected by line immunoassay in comparison with ELISA, systemic lupus erythematosus patients with and without thrombotic events were investigated. Thus, 107 systemic lupus erythematosus patients (48% with deep vein thrombosis or/and arterial thrombosis) and 120 healthy donors were enrolled. Serum antiphospholipid antibodies were detected by ELISA (Orgentec Diagnostika, Germany) and line immunoassay (GA Generic Assays, Germany). Lupus anticoagulant and IgG to cardiolipin and β2GPI but not IgM as well as triple positivity by ELISA and line immunoassay were linked with thrombosis in systemic lupus erythematosus. IgG to phosphatidylinositol and phosphatidylserine by line immunoassay showed significantly higher levels in systemic lupus erythematosus with deep vein thrombosis/arterial thrombosis than without and were independent risk factors for deep vein thrombosis (odds ratio 3.9, 95% confidence interval 1.1, 13.2) and arterial thrombosis (odds ratio 5.1, 95% confidence interval 1.3, 19.8) as well as thrombosis (odds ratio 3.6, 95% confidence interval 1.1, 11.3) and recurrence thereof (odds ratio 6.9, 95% confidence interval 2.1, 22.6), respectively. The occurrence of >4 IgG antiphospholipid antibodies by line immunoassay was an independent risk factor for thrombosis (odds ratio 10.9, 95% confidence interval 1.2, 101.5), arterial thrombosis (odds ratio 14.6, 95% confidence interval 2.5, 86.3), deep vein thrombosis (odds ratio 5.8, 95% confidence interval 1.0, 32.4) and recurrence of thrombosis (odds ratio 35.9, 95% confidence interval 3.8, 342.8). Line immunoassay is a promising multiplex test for the simultaneous detection of criteria and non-criteria antiphospholipid antibodies. Profiling of antiphospholipid antibodies by line immunoassay can differentiate systemic lupus erythematosus patients with thrombosis from systemic lupus erythematosus patients without and assess the risk for thrombosis and recurrence thereof.

COVID-19 and Antiphospholipid Antibodies: Time for a Reality Check?

“…To be identified as having APS, there is a requirement to show evidence of at least one of the laboratory criteria (LA, IgG or IgM aCL, or aβ2GPI), in medium or high titer, as well as their persistence by retesting on a second occasion some 12 weeks later, plus at least one of the clinical criteriathrombosis or pregnancy morbidity. 1,2 While several authors propose added value of noncriteria aPL, [3][4][5][6] current guidelines suggest insufficient evidence for their current inclusion as "criteria" aPL for APS. 2 On the other hand, there is also some debate about the value of some of the established criteria aPL, such as aCL IgM and aβ2GPI IgM, for identification of APS.…”

“…While several authors propose added value of noncriteria aPL, 3 4 5 6 current guidelines suggest insufficient evidence for their current inclusion as “criteria” aPL for APS. 2 On the other hand, there is also some debate about the value of some of the established criteria aPL, such as aCL IgM and aβ2GPI IgM, for identification of APS.…”