Clinical and prognostic significance of antinuclear antibodies in primary antiphospholipid syndrome: french multicenter retrospective study

BackgroundThe antiphospholipid syndrome (APS) is defined by the development of vascular thrombosis, or pregnancy morbidity in the presence of persistent antiphospholipid antibodies (APL). Antinuclear antibodies (ANA) can be detected in primary APS patients without any clinical systemic autoimmune disease. The presence of ANA antibodies could confer a specific phenotype in primary APS.ObjectivesTo evaluate the characteristics of APS patients with antinuclear antibodies without other autoimmune disease (ANA-positive APS patients) in comparison with primary APS without ANA (ANA-negative APS) or secondary APS patients with associated systemic lupus erythematosus (SLE-APS).MethodsClinical and biologic data from 195 APS were retrospectively collected. ANA test was considered to be positive when titers were superior or egal to the 1/80 dilution. ANA-positive APS patients did not fulfilled SLE ACR/EULAR classification criteria.Results40 patients (21%) with ANA-positive APS were included, 77 patients (39%) with primary APS without ANA autoantibodies (ANA-negative APS) and 78 patients (40%) with SLE-associated APS (SLE-APS).Patients with ANA-positive APS presented arterial thrombosis in 20 cases (51%) and venous thrombosis in f 14 cases (41%), adverse obstetrical in 19 cases (51%), non-criteria APS features were noted in 19 cases (51%).ANA-positive APS patients had more non criteria manifestations than ANA-negative APS (48% versus 25%; p=0.01). ANA-positive APS patients had more triple APL positivity and more thrombosis recurrences in comparison with ANA-negative APS patients, respectively (59% versus 18%; p<0.001) and (63% versus 36%; p<0.01). ANA-positive APS and SLE-APS patients had similar clinical manifestations and recurrences.Despite a limited follow-up (28 months (11-50)) none of the ANA-positive APS patients develop SLE.Antiplatelet and anticoagulant therapies were similar for the three groups. SLE-APS patients received more immunomodulatory therapies.ConclusionANA positivity in patients with APS enables to individualize a subset of patients with a more severe phenotype. Whereas the ANA positivity does not seem to be associated with the risk to develop SLE, prospective studies with a longer follow-up are necessary, in particular to evaluate the effect of additional therapies in this subset of APS.Disclosure of InterestsNone declared