• A chronic inflammatory arthritis of unknown etiology
  • Most common autoimmune inflammatory arthritis in adults
  • Persistent synovitis leads to joint destruction and deformity

• Joint pain and/or swelling
• Morning stiffness lasting >1 hour
• Myalgia, fatigue, weight loss, low-grade fever, depression
• Typically involves the joints of the fingers, wrists, toes
  • Upper and lower extremity joints are also affected (eg shoulders, elbows, knees and ankles)

• Syndrome of polymyalgia rheumatica may occasionally be present

Early Rheumatoid Arthritis

• Duration of occurrence of rheumatoid arthritis signs and symptoms is <6 months

Established Rheumatoid Arthritis

• Duration of occurrence of rheumatoid arthritis signs and symptoms is ≥6 months and meets the classification criteria of rheumatoid arthritis

Palindromic Rheumatism

• Follows an episodic pattern
  • Joints may be affected for hours to days followed by symptom-free periods lasting for days to month

Monoarthritis

• May indicate onset of a polyarticular disease
  • Interval between monoarthritis and polyarthritis may extend from days to weeks in patients with progressive disease
• Large joints are frequently affected (eg shoulder, wrist, hip, knee, ankles)
• History of joint trauma may be the initiating event

Extra-articular Involvement

• Anemia, fatigue, pleuropericarditis, neuropathy, scleritis, Sjogren’s syndrome, vasculitis
• Subcutaneous rheumatoid nodules on extensor surfaces of elbows and over Achilles tendons
• Splenomegaly, renal disease

• Smoking increases incidence for developing RA in ACPA-positive patients
• Oral contraceptives decrease RA incidence due to high estrogen content
• Bacteria (eg Escherichia coli, Helicobacter pylori, Mycobacteria, Mycoplasma, Streptococcus), viruses (eg Epstein-Barr virus, rubella, parvovirus) and periodontal disease may also trigger occurrence of RA