Background Anterior uveitis (AU) is considered to be one of the most common extra-articular manifestations of spondyloarthritis (SpA), and its prevalence may vary according to the genetic background of the study population. Uveitis can appear both before and after the onset of osteoarticular symptoms. It can lead to serious complications that can compromise the visual function.

Objectives The aim of this study was to compare demographic, clinical and laboratory data among SpA patients with and without AU.

Methods Cross-sectional study including 190 SpA patients that fullfilled the modified New York criteria. The patients were asked to complete a questionnaire assessing their disease type, age at diagnosis, clinical presentation, disease-activity (BASDAI, ASDAS) and functional-indices (BASFI) and BASMI was calculated. The following parameters were taken out of the patients' files: the presence of HLA-B27 antigen, inflammation biological markers (ESR, CRP), and conventional radiographs of spine, hip and sacroiliac joints were evaluated. Ocular involvement passively reported by the patients and confirmed by ophthalmological exams was noted and the group with AU diagnosis (current or past) was compared to those without uveitis. The statistical analysis was performed using SPSS 21.0 software, and p<0.05 was taken to indicate statistical significance. To compare the differences between the groups, Mann-Whitney U, χ² and Fisher tests were used.

Results 190 patients were included, of which 56.3% were males, with median age of 46.0 (range 21–79) years. 58 (30.5%) patients had AU, which was significantly more frequent in patients with ankylosing spondylitis (84.5% of patients with AU) comparing with the other subtypes of SpA (p=0.01). There were no statistically significant differences in age at diagnosis, time to diagnosis or gender between the two groups. However, median age and disease duration were significantly greater in SpA patients with AU than those without AU (50.5 vs 44.0 years, p=0.015 and 24.0 vs 15.9 years, p<0.001 respectively). HLA-B27 was positive in 60,3% of patients with AU, comparing with 43.2% in those without AU (p<0.005). Ankylosis of bilateral sacroiliac joints was more frequent in patients with AU (46.6% vs 20.9%, p<0.001). The patients with AU had less frequently skin lesions and dactylitis (10.3% vs 30.3%, p=0.02 and 0% vs 7.5%, p=0.024), but there were no differences in the prevalence of peripheral arthritis or enthesitis. BASMI was significantly higher in patients with AU (median 4.9 vs 4.0, p=0.041), but there were no significant differences in disease activity, functional outcomes.

Conclusions This study showed that AU could be more frequently seen in HLA-B27 positive patients with long-standing SpA, especially ankylosing spondylitis, and may be less frequent in patients with skin lesions and dactylitis.

Disclosure of Interest None declared