Rheumatoid arthritis (RA) is a chronic inflammatory disease that mostly affects the joints, among other tissues.
- RA is characterized by a symmetrical and bilateral inflammation of the synovium of joints, with progressive erosion and destruction of the affected joints.
- Virtually every joint can be affected apart from the distal interphalangeal joints (DIP).
- Epidemiology. Population prevalence of 0.5% to 1% and an annual incidence of 12-1,200 per 100,000 population. Females are more commonly affected.
- Etiology. RA is a complex multifactorial (genetic and environmental) disease with an uncertain etiology.
- Environmental. Associated with smoking and periodontitis.
- Genetics. HLA-DR1 and HLA-DR4 genes.
Clinical presentation
Course pattern
RA typically appears in one of three course patterns:
- Single attack with complete remission (monocyclic)
- Remittent attacks with complete or incomplete remission periods (polycyclic, most common)
- Progressive disease without remissions
Disease course
- Early disease presents with general symptoms (weakness, fever, malaise), and joint swelling and pain. Synovitis and joint erosion are evident in radiographic