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Objectives To investigate whether autoantibodies can identify SLE sub-phenotypes in a well-characterized Sudanese SLE cohort, and to explore associations with clinical manifestations. Our aim is to ddress the underrepresentation of non-European ancestries in current research and the need for insights into populations with higher disease severity.Methods A cross-sectional study involving 95 Sudanese patients with SLE, who were diagnosed based on the revised 1982 ACR criteria. Autoantibodies against Sm, U1RNP, dsDNA, ribosomal P, histones, SSA/Ro52, SSA/Ro60, and SSB/La were quantified with a bead-based multiplex immunoassay. Anti-phospholipid antibodies (aPL) including anti-cardiolipins, anti-B2GP1, and anti-phosphatidylserine/prothrombin were quantified with using the Aptiva system based on a particle-based multi-analyte technology. National-based cutoffs were used to determine a positive reaction. The autoantibodies positivity status was used to unsupervised cluster the patients; using Gower’s distance and partition around medoids. A combination of metrics for cluster’s cohesivesness (Silhouette index), bootstrap stability (Jaccard index), and expert opinion, guided the selection of number of clusters. Using logistic regression adjusted for sex and age at inclusion, we tested associations between clusters and clinical manifestations (ACR criteria components, vascular events and SLEDAI).Results Our preliminary results suggest that Sudanese patients can be grouped into three clusters ( figure 1A–C), where aPL dominate cluster 1, anti-Sm, -U1RNP, -dsDNA, -ribosomal P, and aPL cluster 2; and cluster 3 has patients with the least frequency for the tested autoantibodies (figure 1D). Cluster 2 showed significant associations with SLEDAI and mucocutaneous manifestations (figure 1E).Abstract PO:08:219 Figure 1Conclusions Having several autoantibody specificities, patients in cluster 2 represent a group that may have a more severe disease outcome. Our approach might be valuable to discriminate individuals with different disease burdens.