Background An inhibitory effect of TNFa blockers on radiographic progression at two years has not been demonstrated until now in patients with Ankylosing Spondylitis. Moreover, in studies evaluating the structural progression of non-radiographic axial Spondylarthritis patients did not receive biological therapy or a small percentage of them did.

Objectives To assess radiographic progression in the spine and sacroiliac joints at two years in a cohort of patients with non-radiographic axial Spondyloarthritis treated with TNFa blockers.

Methods After systematic review of clinical registries, nineteen patients with non-radiographic axial Spondyloarthritis were selected for this analysis based on availability of spinal (cervical and lumbar) and anteroposterior pelvic radiographs at baseline and after two years of follow-up with the same treatment with TNFa blocker.

Nineteen patients fulfilled ASAS classification criteria for axial Spondyloarthritis but did not fulfil radiological criterion of the modified New York criteria for Ankylosing Spondylitis (bilateral sacroiliitis of at least grade 2 or unilateral grade 3-4).

Spinal radiographs were scored by two trained readers (LJ and AM) according to the Stoke Ankylosing Spondylitis Spine Score (mSASSS) system and sacroiliac joints according to the New York criteria scoring system, in a chronological order (at baseline and after two years with the same treatment).

Results The nineteen patients fulfilled ASAS classification criteria for axial Spondyloarthritis and six had active inflammation demonstrated by MRI. Twelve patients received Adalimumab, two received Infliximab and five received Etanercept.

mSASSS score was zero at baseline and after two years of treatment in all patients (none of the patients developed structural damage in spine).

There was not radiological progression in sacroiliac joints in none of the patients. None of the nineteen patients fulfilled the modified New York criteria for Ankylosing Spondylitis at two years with TNFa blockers therapy.

Conclusions None of the patients of our cohort with non-radiographic axial Spondylarthritis showed radiographic progression in the spine or sacroiliac joints at two years of treatment with TNFa blockers.

Disclosure of Interest None Declared