AB0869 Prevalence of spondyloarthritis in patients with anterior uveitis

Background Anterior uveitis (AU) is a common extraarticular manifestation in spondyloarthritis (SpA). The disease can precede the typical axial and peripheral features. Additionally, some studies had described the imaging signs of sacroiliac involvement in patients with AU lacking chronic back pain. Objectives The aim of this study was to examine patients with AU, to determine whether the patients already fulfil criteria for axial and/or peripheral SpA and to stratify risk factors for SpA development. Methods We recruited 27 patients without prior rheumatologic diagnosis who developed at least one episode of AU. The clinical data were collected and rheumatology examinations were performed by trained rheumatologists. Magnetic resonance imaging (MRI) of sacroiliac joints (SIJ) was read by trained rheumatologist who was blinded to the patient data. Patients were further divided into SpA subsets (axial: imaging and clinical arm and peripheral SpA) fulfilling The Assessment of SpondyloArthritis international Society (ASAS) classification criteria 1 and non-SpA subset. The ASAS modified Berlin algorithm for diagnosis of axial SpA 2 (axSpA) was also applied. Results Bone marrow oedema (BME) was found in 63.0% (n=17) of all patients with AU, however 40.7% (n=11) had highly suggestive BME 3 corresponding to typical findings in sacroiliitis. Altogether, 22.2% (n=6) referred inflammatory back pain, 48.1% (n=13) referred non-inflammatory back pain and 29.6% (n=8) did not refer back pain. The diagnosis of SpA was confirmed in 44.4% (n=12) of all patients with AU, 33.3% (n=9) patients fulfil the imaging arm and 7.4% (n=2) fulfil the clinical arm of ASAS classification criteria for axSpA, 7.4% (n=2) patients fulfil ASAS classification criteria for peripheral SpA (one patient fulfil both axial and peripheral criteria). The diagnosis of axSpA according to the ASAS modified berlin algorithm was confirmed in 37.0% (n=10) patients. Analysis of clinical characteristics showed significant difference between Ankylosing Spondylitis Disease Activity Score (ASDAS) in SpA vs. non-SpA (1.5±0.7 vs 0.7±0.6, p=0.01, respectively), and remained significant in axSpA and also in those fulfilling only imaging arm of axial SpA (i-axSpA) (1.4±0.7, 1.3±0.7 vs. 0.7±0.6, p=0.01, p=0.04, respectively). The levels of CRP were significantly higher in SpA and axSpA compared to non-SpA subsets (8.3±10.5, 7.1±10.1 vs. 1.8±1.6 mg/L, p=0.02, p=0.05, respectively). Presence of back pain was increased in SpA and similarly in axSpA as well as i-axSpA compared to non-SpA subsets (91.7%, 100%, as well as 100% vs. 53.3%, p=0.04, p=0.01, p=0.02, respectively). Furthermore inflammatory back pain was more frequently described in axSpA and i-axSpA compared to non-SpA subsets (45.5%, 44.4% vs. 6.7%, p=0.05, p=0.01, respectively). Conclusions More than one third of patients with anterior uveitis fulfilled the criteria for axial or peripheral SpA. Furthermore, these patients had significantly higher presence of back pain, ASDAS and serum CRP levels. Inflammatory back pain was significantly increased in patients classified as axSpA. References [1] Rudwaleit, et al. Ann Rheum Dis2009;68:777–83. [2] Rudwaleit, et al. Ann Rheum Dis2004;63:535–543. [3] Rudwaleit, et al. Ann Rheum Dis2009;68:1520–1527. Acknowledgements Supported by MH CR 023728, SVV 260373, AZV – 17–33127A Disclosure of Interest None declared