Definition :Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease of unknown cause. The hallmark feature of this condition is persistent symmetric polyarthritis (synovitis) that affects the hands and feet, although any joint lined by a synovial membrane may be involved. Extra-articular involvement of organs such as the skin, heart, lungs, and eyes can be significant.
The cause of RA is unknown. Genetic, environmental, hormonal, immunologic, and infectious factors may play significant roles. Socioeconomic, psychologic, and lifestyle factors may influence disease outcome.
- The annual incidence is approximately 3 cases per 10,000 population.
- The prevalence rate is approximately 1%, increasing with age and peaking at age 35-50 years.
- Women are affected by RA approximately 3 times more often than men.
- The pathogenesis of RA is not completely understood.
- An external trigger (eg, infection, trauma) that triggers an autoimmune reaction
- leading to synovial hypertrophy and chronic joint inflammation along with the potential for extra-articular manifestations.
- Is theorized to occur in genetically susceptible individuals.
- Synovial cell hyperplasia and endothelial cell activation are early events in the pathologic process
- Genetic factors and immune system abnormalities contribute to disease propagation.
- Abnormal production of numerous cytokines, chemokines, and other inflammatory mediators has been Demonstrated in patients with RA.
- Inflammation and exuberant proliferation of synovium leads to destruction of various tissues, including cartilage, bone, tendons, ligaments, and blood vessels.By Dr Shall