RA Patho

• Key points about RA

  • Autoimmune disease
  • Systemic - affects whole body
  • Inflammatory
  • Chronic
  • Destructive towards joints
  • Polyarthritis (non-articular features also)
  • Affects multiple joints (especially synovial) especially peripheral joints
  • Disease activity variable with flares and remissions
• Aetiology of Rheumatoid Arthritis

  • Hormonal link – influence at onset and with flares (e.g., pregnancy, peri-menopause)
  • Environmental trigger – unknown – links to bacteria, virus, pollutants, smoking, coffee, link with low socioeconomic status
• Pathology of RA at synovial joint

  • First area that seems to be affected is the synovial membrane - almost like an invasion by antigen (but is more like the bodys failure to recognise synovium as “self”, perceiving it as an antigen)
  • Triggers antibody/antigen reaction and inflammatory response
• Pathology of RA at synovial joint

  • Release of proinflammatory mediators, cytokines, prostaglandins etc
  • These sensitize nociceptors and induce vasodilation
  • This causes PAIN AND SWELLING

  
• Pathology of RA at synovial joint

  • Synovial blood vessels proliferate, dilate and become congested
  • Synovial membrane becomes hypertrophic and hyperplastic → more synovial fluid
  • Infiltration with chronic inflammatory cells - macrophages, T and B lymphocytes, plasma cells