POS0706 PERFORMANCES OF DIFFERENT CLASSIFICATION CRITERIA FOR SYSTEMIC LUPUS ERYTHEMATOSUS IN A SINGLE CENTER COHORT FROM TURKEY

Background: Recently developed EULAR/ACR classification criteria for systemic lupus erythematosus (SLE) have important differences compared to the 2012 Systemic Lupus International Collaborating Clinics (SLICC) SLE and revised 1997 American College of Rheumatology (ACR) criteria: The obligatory entry criterion antinuclear antibody (ANA) positivity is introduced a “weighted” approach used 1 . Sensitivity specificity these three been debated may vary in different populations clinical settings. Objectives: We aim compare performances sets/rules large cohort patients relevant diseased controls from reference center with dedicated clinics other autoimmune/inflammatory connective tissue diseases Turkey. Methods: reviewed medical records laboratory features all sets criteria. Criteria were analysed based on sensitivity, positive predictive value, negative using diagnosis at least 6 months follow-up as gold standard. A subgroup analysis was performed ANA both controls. that did not fulfil SLICC 2019 fulfilled evaluated. Results: total 392 294 non-SLE (48 undifferentiated disease, 51 Sjögren’s syndrome, 43 idiopathic inflammatory myopathy, 50 sclerosis, 52 primary antiphospholipid 15 rheumatoid arthritis, psoriatic arthritis 20 ANCA associated vasculitis) included into study. Hundred fourteen (16.6%) negative. more than 90% value (Table 1). Specificity highest ACR Negative 76.9% criteria, 88.4% 91.7% In only patients, sensitivity 79.6% 92.2% 96.1% 92.6% 87.8% 85.2% Eleven clinically diagnosed had insufficient number items Both by 16 controls: 9 5 one dermatomyositis sclerosis. Table 1. Sensitivity, ACR, (+) (-) (%) Positive Predictive Value 308 84 279 78.6 95.4 94.9 76.9 357 35 26 268 91.1 93.2 91.2 88.4 368 24 28 266 93.8 92.9 90.5 91.7 Conclusion: this cohort, although sufficient specificity, are lowest. Overall, comparable performance, but if cases analysed, decrease less 90%. Some lacked Mostly, syndrome or prone misclassification recent References: [1]Aringer M, Costenbader K, Daikh D, et al. European League Against Rheumatism/American erythematosus. Ann Rheum Dis 2019;78:1151-1159. Disclosure Interests: None declared