Reactive arthritis. Immune-mediated synovitis or joint infection

Reactive arthritis is one form of the seronegative Spondyloarthropathies. Susceptibility to reactive arthritis is closely linked to individuals who have the genetic predisposition to the HLA-B27 allele (gene form). Although there is a reactive-inflammatory joint reaction present, the synovium is not damaged by infectious agents (bacteria, fungi, or virus). This article discusses the pathogenesis of reactive arthritis.