原発性抗リン脂質抗体症候群

OBJECTIVE: To evaluate remission, low disease activity, and relapse in patients with systemic lupus erythematosus (SLE) according to age at disease onset. METHODS: We conducted a retrospective cohort study including patients classified with SLE according to the 2019 EULAR/ACR criteria. Patients were grouped by age at onset as juvenile-onset SLE (jSLE, <18 years), adult-onset SLE (aSLE, 18-49 years), and late-onset SLE (lSLE, ≥50 years). Patients with other autoimmune diseases were excluded, except antiphospholipid syndrome and Sjögren. Clinical data and outcomes were obtained from medical records. Remission was defined according to DORIS, low disease activity according to LLDAS, and relapse according to the SELENA-SLEDAI Flare Index. RESULTS: A total of 289 patients were included: 96 with jSLE, 96 with aSLE, and 97 with lSLE; 90.5% female. At diagnosis, jSLE patients had higher disease activity. Neuropsychiatric manifestations were more frequent in jSLE, while mucocutaneous involvement and nephritis predominated in aSLE. Remission and LLDAS were achieved more frequently in lSLE; concordantly, lSLE independently predicted remission and LLDAS (HR 2.8; 95% CI 1.9-4.0 and HR 2.4; 95% CI 1.7-3.4; p < 0.001). Relapses were more frequent in jSLE (87.5%) compared with aSLE (66.7%) and lSLE (24.7%; p < 0.001). Factors associated with relapse were jSLE (HR 2.1; 95% CI 1.5-2.9; p = 0.008) and constitutional manifestations at onset (HR 1.6; 95% CI 1.2-2.4; p = 0.048). Mortality was higher in lSLE, with infections as the main cause. CONCLUSION: Juvenile-onset SLE was associated with higher relapse rates, whereas late-onset SLE was independently associated with achieving remission and LLDAS.

INTRODUCTION: Thrombocytopenia is a frequent haematological complication among SLE patients and ranges from asymptomatic to severe, which over time could progress into bleeding. AIM: The current study explored the role of PVT1/miR-181a as an upstream regulator of FOXP3/RORγt and their associated interleukins in the pathogenesis of SLE-associated thrombocytopenia, and coexistence of antiphospholipid antibodies. METHODS: Sixty SLE patients with thrombocytopenia and forty without thrombocytopenia, together with forty healthy controls were recruited, and blood samples were drawn. The gene expression of PVT1, miR-181a, FOXP3, and RORγt were measured using RT-PCR, whereas the serum concentrations of IL-23, IL-10, lipocalin2, and MMP9 were measured using ELISA. RESULTS: The gene expression of miR-181a and RORγt were upregulated, PVT1 and FOXP3 were downregulated, levels of IL-23, lipocalin2, and MMP9 were increased, and IL-10 were lower among thrombocytopenic SLE patients relative to non-thrombocytopenic and healthy controls. Moreover, miR-181a and RORγt were upregulated, PVT1 and FOXP3 were downregulated, IL-23 level was increased, and IL-10 was decreased among thrombocytopenic SLE patients with positive antiphospholipid antibodies. CONCLUSION: Collectively, PVT1/miR-181a could be an upstream regulator of RORγt/FOXP3 and their associated pro-inflammatory and anti-inflammatory markers IL-10/IL-23 in the pathogenesis of SLE-associated thrombocytopenia. These biomarkers in a panel could be valuable in supporting the diagnosis of thrombocytopenia. Furthermore, understanding the role of the PVT1/miR-181a and RORγt/FOXP3 axes could be valuable in underscoring the co-existence of thrombocytopenia and antiphospholipid syndrome, thus holding the potential for monitoring the progression of associated bleeding and thrombosis risk and tailoring therapeutic interventions.

Triple-positive antiphospholipid syndrome (APS) represents a high-risk serologic phenotype associated with recurrent thrombosis and systemic lupus erythematosus (SLE). Direct oral anticoagulants (DOACs), particularly rivaroxaban, have demonstrated inferior outcomes compared with vitamin K antagonists in this population. We report a case of a patient with long-standing SLE and persistently triple-positive APS who developed Libman-Sacks endocarditis following a switch from warfarin to rivaroxaban. The patient had biopsy-proven class V lupus nephritis and had remained clinically stable on long-term warfarin therapy for several years. Transthoracic echocardiography demonstrated underlying rheumatic mitral valve disease with newly developed mobile vegetations measuring 10-15 mm. Blood cultures obtained prior to antibiotic exposure were negative, and inflammatory markers were not suggestive of infection. Rivaroxaban was discontinued, and warfarin was reinstated with bridging therapy. Prednisolone (40 mg daily) was initiated, and follow-up echocardiography demonstrated a reduction in vegetation size with clinical improvement. This case highlights a temporal association between rivaroxaban use and valvular thrombotic lesions in high-risk APS. Improvement was likely multifactorial, reflecting combined effects of anticoagulation, escalation of immunosuppression, and underlying valvular disease. These findings support current recommendations favoring vitamin K antagonists over DOACs in patients with triple-positive APS. Cite this article as: Saleh I, Salman S, Alkady A, Saqabi FA. Libman-Sacks endocarditis in triple-positive antiphospholipid syndrome following switch from warfarin to rivaroxaban: improvement after reinstitution of warfarin and escalation of immunosuppression. Eur J Rheumatol. 2026, 13(2), 0009, doi: 10.5152/ eurjrheum.2026.26009.