422 Anti-rnp/sm antibodies plus lupus anticoagulant as risk factor for thrombosis in patients with systemic lupus erythematosus

Background and aimsThrombosis still remains as main cause of morbidity and mortality in SLE patients. Results from a recent study identified a strong association of anti-RNP/Sm abs+LA with thrombosis. We aimed to validate this associationMethodsWe studied 63 SLE patients (>4 criteria/ACR) with confirmed history of thrombosis after SLE diagnosis. As controls, 63 SLE patients without thrombosis, matched by age, gender and lupus duration were included. Disease characteristics, medication, traditional risk factors for thrombosis and thrombotic event information were retrieved from clinical files. A blood sample was drawn to determine anti-cardiolipin (IgG/IgM), antiß2-GP1 (IgG/IgM), LA, anti-RNP/Sm and anti-Sm antibodies. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) and Likelihood Ratios (LR) were calculated.ResultsOne hundred and twenty six SLE patients were studied. Cases and controls were similar in age, gender and disease duration (p=NS). There were no differences in the prevalence of traditional risk factor for thrombosis between cases and controls (p=NS). Among patients with thrombosis a higher frequency of anti-RNP/Sm (83% vs 62%, p