A 45-year-old woman presents to her primary care physician for evaluation of joint pain and fatigue, which has been present over the past 6 months. She states that it takes her an hour to gain full mobility of her fingers in the morning, which makes it difficult to button her coat. Her past medical history is significant for atrial fibrillation, for which she takes flecainide. Vital signs are significant for a temperature of 99°F (37.2°C) and are otherwise within normal limits. Physical examination reveals bilateral swan neck deformities of the fingers, and serum studies indicate a positive rheumatoid factor.
Which of the following describes the most likely appearance of this patient’s affected joints?
- A) Monosodium urate crystal deposition
- B) Osteophyte formation with asymmetric joint space narrowing
- C) Pencil-in-cup deformity with dactylitis
- D) Purulent synovial fluid containing bacteria
- E) Synovial hyperplasia with inflammatory pannus
E) Synovial hyperplasia with inflammatory pannus
This describes rheumatoid arthritis (RA), a non-infectious inflammatory disease often accompanied by systemic symptoms such as fever, fatigue, and rheumatoid nodules. Note that while rheumatoid factor is a sensitive marker for RA (present in up to 90% of individuals with RA), it is not specific and may also be found in individuals with Sjogren syndrome, systemic lupus erythematosus, polymyositis, and a small percentage of healthy individuals.
Answer choice A: Monosodium urate crystal deposition, is incorrect. This describes gout, which is an inflammatory crystal deposition disease. Gouty attacks occur acutely and classically occur in the metatarsophalangeal joint of the great toe.
Answer choice B: Osteophyte formation with asymmetric joint space narrowing, is incorrect. This describes the typical changes of osteoarthritis, a non-inflammatory degenerative joint disease caused by mechanical wear and tear. The pain associated with osteoarthritis typically worsens throughout the day and improves with rest.
Answer choice C: Pencil-in-cup deformity with dactylitis, is incorrect. This describes psoriatic arthritis, which is a seronegative spondyloarthropathy. Psoriatic arthritis is associated with skin and nail changes and is typically localized to the distal interphalangeal joints of the hands.
Answer choice D: Purulent synovial fluid containing bacteria, is incorrect. This describes septic arthritis, which presents acutely as a red, swollen, and painful joint. It is most commonly caused by a gonococcal infection in someone who is sexually active.
Key Learning Point
Rheumatoid arthritis is characterized by synovial hyperplasia with inflammatory pannus formation and is often accompanied by systemic symptoms.