Ab0038 “Rheumatologic” Clinical Profile of Vexas Syndrome: Results From a Multi-Institutional Spanish Survey

Background: VEXAS syndrome is characterized by heterogeneous rheumatologic and hematologic manifestations driven by somatic UBA1 gene mutations. It, however, requires a more precise clinical definition. Objectives: This study aims to comprehensively describe the clinical profile of VEXAS patients (VP) managed in Spanish rheumatologic units. Methods: A nationwide survey across 126 rheumatologic units within Spanish public hospitals identified 38 VP based on clinical compatibility, characteristic bone marrow biopsy (BMB) findings, and/or confirmed UBA1 gene mutations. Demographic, clinical, laboratory, and outcome data were retrospectively collected from medical records in a standardized form. Results: Thirty-eight VP were identified. All were men and Caucasian, with a mean age at diagnosis of 73.18 (±SD 9.08) years. Constitutional symptoms and fever were detected in 30 (78.95%) patients, as well as arthritis, and chondritis (including nasal chondritis, perichondritis and epiglottis' chondritis) was found in 20 (52.63%) cases. Thirty-two (84.21%) patients presented 1 or more skin manifestations, being the most frequent ones: Sweet syndrome (n=19, 50%), leukocytoclastic vasculitis (n=9, 23.68%), erythema nodosum (n=8, 21.05%), Jessner's lymphocytic infiltration of the skin (n=2, 5.26%), and lupus-like skin lesions (n=2, 5.26%). Pulmonary involvement ocurred in 15 (39.47%) cases, including lung infiltrates (n=7), interstitial lung disease (n=5), pleurisy (n=2), and alveolar hemorrhage (n=1). Remarkably, renal involvement (acute renal failure n=3, nephrotic syndrome n=2, and IgA nephropathy n=1) attributed to VEXAS syndrome, which had not previously reported, occurred in 6 patients (15.78%). Other clinical manifestations are included in Table 1. Anemia was found in 94.73% cases, being macrocytic in 31 (81.58%) of them; 25 (65.79%) presented thrombocytopenia as well; furthermore, 19 (50%) met criteria for MDS. Other laboratory findings are included in Table 2. Conclusion: Our VEXAS syndrome cohort aligns with reported rheumatologic manifestations, with a noteworthy inclusion of renal involvement in 15% of patients, a new finding at the time of this publication. This detailed characterization enhances our understanding of VEXAS syndrome's clinical spectrum. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.