The Concept and Overview of Spondyloarthritis / 대한내과학회지

ABSTRACT

The spondyloarthritis (SpA) is a group of chronic inflammatory rheumatic diseases in association with HLA-B27. They share the clinical features including sacroiliitis, spondylitis, oligoarthritis, enthesitis and extra-articular involvement. Recently ASAS proposed new classification criteria sets of axial and peripheral SpA. They were designed to include non-radiographic SpA, thus can guide the early diagnosis of disease before the structural damage occurs. SpA has a strong genetic predisposition. Non-MHC genes, such as IL23R and ERAP1, as well as HLA-B27 were confirmed as susceptibility genes through several GWAS. Major pathology in SpA is entheseal inflammation and new bone formation. Intrinsic ability of HLA-B27 to trigger innate immune response and several proinflammtory cytokines may contribute to the inflammation in SpA. New bone formation could be explained by a mechanism, partly or completely independent of the inflammatory process.