Chronic inflammation of ankylosing spondylitis

Ankylosing spondylitis (AS), a prototype of spondyloarthritis (SpA), is a chronic inflammatory disease involving spine, peripheral joints and peri-articular soft tissues. The spectrum of SpA can be classified to 5 diseases categories: ankylosing spondylitis, psoriatic arthritis (PsA), reactive arthritis (ReA), inflammatory bowel diseases-associated arthritis, and undifferentiated spondyloarthritis (USpA). Common clinical features of SpA are chronic inflammatory arthritis over spine, sacroiliac joints, peripheral joints and enthesitis. Up to 45% of AS patients may have extra-articular manifestations, such as uveitis, psoriasis, bowel inflammation and nephropathy. The etiology is unknown, but probably related to genetics and immune dysregulation that was triggered by environmental factors, mainly infection and trauma. Management of AS are focused on control of chronic inflammation by non-steroidal anti-inflammatory drugs (NSAID), disease-modifying anti-rheumatic drugs (DMARD) and anti-tumor necrosis factor biological agents.