Background Behcet's disease (BD) is a multisystem inflammatory disease with oral and genital ulcers. It was classified as one of the seronegative arthritis in sixties and seventies due to occurrence of oral ulcers, arthritis, uveitis, and erythema nodosum like symptoms. The prevalence of sacroilitis was detected as 65% with conventional radiography in early reports. However in a controlled study, prevalence of sacroilitis was reported as 35% which was comparable with the healthy control group. Magnetic resonance imaging (MRI) is the most sensitive method for detection of sacroiliitis in patients with spondyloarthropathies.

Objectives In this study we aim to determine the prevalence of sacroiliitis in patients with Behçet disease by using MRI and compare with the healthy control group.

Methods Fifty patients (25 M, 25 FM) having Behçet's disease according to international Behçet's disease study group classification criteria were included into the study. Fifty healthy people (25 M, 25 FM) who did not have any musculoskeletal symptom were taken as control group. Medical history was taken and physical examination was performed for both study and control groups. Subjects in control group who had musculoskeletal symptoms were excluded from the study. Routine laboratory tests were obtained from the study group. Sacroiliac joint MRI exams were taken for both study and control groups and evaluated by two radiologists who were blinded to the subjects.

Results Sacroiliitis were detected in seven (14%) patients with BD and in eight (16%) subjects in the control group. There was no statistically significant difference between two groups for the prevalence and presence of active and chronic findings of sacroiliitis (p>0.05). No correlation was detected between acute phase reactants andsacroiliitis in patients with Behçet's disease.

Conclusions This is the first study which researches the prevalence of sacroiliitis by using MRI in patients with Behçet's disease. Although Behçet's disease has symptoms of spondyloarthropaties the prevelance of sacroiliitis which is most important clinical finding of spondyloarthropathy is not different from the healthy control group.

Acknowledgements This study was supported by Pamukkale University Scientific Research Projects Coordination Unit

Disclosure of Interest None declared

DOI 10.1136/annrheumdis-2014-eular.4085