Rheumatoid arthritis (RA) is an autoimmune disease. It causes pain, swelling, stiffness, and loss of function in the joints. RA usually affects the same joint on both sides of the body. It occurs mostly in the:

  • Fingers
  • Wrists
  • Elbows
  • Shoulders
  • Jaw
  • Hips
  • Knees
  • Toes

Rheumatoid Arthritis
rheumatoid arthritis
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RA is caused by a combination of genetic and environmental factors that trigger an abnormal immune response. Possible causes:

  • Genetic factors—Certain genes that play a role in the immune system are associated with RA development.
  • Defects in the immune system can cause ongoing inflammation.
  • Environmental factors—Certain infectious agents, such as some viruses or bacteria, may increase susceptibility to RA.
  • Other factors—Some evidence suggests that hormonal factors may promote RA development in combination with genetic factors and environmental exposure.