Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease of connective tissue, primarily affecting joints in a symmetrical pattern, leading to their progressive destruction, deformation, and functional impairment. It is classified as a systemic disease since extra-articular organs can also be involved.
Epidemiology
- Prevalence in the general population: approximately 0.5–1%.
- Women are affected 2–3 times more often than men.
- Peak incidence: 30–50 years, but the disease can occur at any age, including childhood (juvenile idiopathic arthritis).
Etiology and Pathogenesis
The exact cause is unknown, but the disease is multifactorial:
- Genetic predisposition (HLA-DR4, HLA-DR1).
- Immune mechanisms: activation of T- and B-lymphocytes, production of rheumatoid factor (IgM against Fc fragment of IgG), anti-CCP antibodies.
- Environmental factors: infections, smoking, hormonal influences.
The key link is chronic autoimmune inflammation with the formation of granulation tissue (pannus), which destroys cartilage and bone.
Clinical Manifestations
Articular
- Symmetrical polyarthritis of small joints of hands and feet.
- Morning stiffness lasting more than 30 minutes.
- Pain, swelling, restricted mobility.
- Progressive deformities (“swan neck,” “buttonhole,” ulnar deviation).
Extra-articular
- Subcutaneous rheumatoid nodules.
- Pulmonary involvement (interstitial fibrosis, pleuritis).
- Vascular manifestations (vasculitis).
- Cardiac involvement (pericarditis, increased risk of atherosclerosis).
- Sjögren’s syndrome (dry eyes and mouth).
Diagnosis
Diagnosis is based on clinical, laboratory, and imaging data.
- Clinical: symmetrical polyarthritis, morning stiffness > 6 weeks.
- Laboratory: rheumatoid factor, anti-CCP antibodies, elevated ESR, CRP.
- Imaging: X-ray (erosions, osteoporosis, joint space narrowing), US/MRI (synovitis, early erosive changes).
Diagnostic criteria: ACR/EULAR 2010.
Treatment
Goal: achieve remission or low disease activity.
1. Pharmacological
2. Non-pharmacological measures
- physiotherapy, exercise, occupational therapy,
- psychological support, smoking cessation,
- surgical interventions (joint replacement) for severe deformities.
Prognosis
- Without treatment — progressive disability.
- Modern “treat-to-target” strategies significantly improve outcomes.
- Early initiation of methotrexate or biologics can lead to sustained remission.