Advances in classification, basic mechanisms and clinical science in ankylosing spondylitis and axial spondyloarthritis.

The field of spondyloarthritis (SpA) has seen huge advances over the past 5 years. The classification of axial disease has been redefined by the axial SpA criteria that incorporate disease captured before radiographic damage is evident as well as established erosive sacroiliac joint disease. Our knowledge of genetics and basic immunological pathways has progressed significantly. In addition, revolutionary progress has been achieved with the availability of tumour necrosis factor inhibitors for treating patients with moderate to severe disease. In parallel, several of novel biomarkers have been identified that show significant promise for the future. Advances in magnetic resonance imaging have helped define positive disease. We have identified that T1 and short tau inversion recovery sequences are best for the diagnosis of axial SpA, and gadolinium contrast is not additive for diagnosis. Progress has been made in identifying potential agents and strategies that reduce radiographic progression. Several referral strategies aimed at appropriate identification of patients have been trialled and found to be effective. There is still substantial work ahead, but the advances of the last 5 years have made a huge and tangible difference at the clinical coalface, and we suggest that this trend will continue.