Background Early axial spondyloarthritis may resolve spontaneously, remain undifferentiated, or progress to ankylosing spondylitis or another spondyloarthritis. There are a need for improving the early diagnosis of ankylosing spondylitis (AS) and other spondyloarthritis (SpA).

Objectives To assess the level of agreement between a SpA at baseline and 6 years later in cohort of patients with recent-onset axial spondyloarthritis.

Methods Patients with duration of inflammatory back pain less than 2 years (between 2006 and 2008) were included. Patients followed-up in our department during about 6 years. And in patients who not followed-up in our department physician was contacted by phone to determine the final diagnosis.

Results Diagnosis at baseline and 6 years later was known for 50 patients. At baseline all patients were diagnosed as axial SpA by ESSG, mean age 23.9 years, mean duration IBP 17 month, MRI sacroiliitis - 44% patients, HLA B27 positive were 96% patients, and peripheral arthritis/enthesitis have 28% patients. Mean follow-up was 5.9 years, and in the end of 2013 year 56% patients have AS; 20% patients have nr-axSpA (ASAS2009): 1 patient associated with psoriasis, 1 patients associated with IBD; 4% patients have peripheral SpA (ASAS 2012), 20% patients were healthy or have full remission. At baseline rise erythrocyte sedimentation rate (ESR) observed more frequently in patients with outcome to AS. Sacroiliitis is seen on MRI was a good predictor of future AS (likelihood ratio [LR] 3,0; specificity 67,6%) but not HLA–B27 positivity (LR 1,0; specificity 6,7%)

Conclusions Only 56% nr-axSpA patients became AS after 6 years follow-up. MRI sacroiliitis and high erythrocyte sedimentation rate were predictors of future ankylosing spondylitis.

Disclosure of Interest None declared

DOI 10.1136/annrheumdis-2014-eular.3324