18th January 2024

Pathophysiology

RA is a chronic, systemic autoimmune disease primarily affecting the lining of synovial joints. The deformities typically associated with RA occur due to the stretching of tendons and ligaments and destruction of joints through the erosion of cartilage and bone.

A combination of genetic and environmental factors can be responsible for triggering RA. Inherited genes in the human leukocyte antigen (HLA) major histocompatibility complex (MHC) are of particular importance. The presence of HLA DR4/DR1 in RA patients is associated with increased disease severity. Smoking is the best-defined environmental stimulus, likely due to repeated activation of innate immunity, especially at mucosal surfaces.