Introduction: C-reactive protein/albumin (CAR) and albumin/fibrinogen (AFR) ratios are novel biomarkers of inflammation that indicate activity status, severity, and response to treatment in systemic lupus erythematosus (SLE); however, the potential value of these ratios in differentiating SLE patients from healthy individuals has not been evaluated. Objective: To evaluate the value of CAR and AFR as potential biomarkers for differentiation of SLE. Material and methods: Analytical case-control study, performed in a SLE group (n=71) and a control group (n=50). Clinical, inflammatory and cardiometabolic parameters with possible diagnostic value (CAR and AFR) were quantified. The diagnostic threshold was estimated by receiver operating characteristic (ROC) curve, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each ratio and 95% confidence in...