Risk Factors

Genetics

• Rare in siblings, but many studies have demonstrated increased frequencies of various human leukocyte antigen markers in juvenile idiopathic arthritis.
• Each marker may be associated with a different subtype of juvenile idiopathic arthritis.
  • Human leukocyte antigen-DR4: Rheumatoid factor-positive (RF+) polyarticular juvenile idiopathic arthritis
  • Human leukocyte antigen-DR1: Oligioarticular disease without uveitis
  • Human leukocyte antigen-DR5: Oligioarticular juvenile idiopathic arthritis with uveitis
  • Human leukocyte antigen-B27: ERA
  • Human leukocyte antigen-A2: Early-onset pauciarticular juvenile idiopathic arthritis