Systemic-onset JIA is most characteristically associated with which fever pattern?

Systemic-onset JIA is most characteristically associated with which fever pattern?

• A. Positive RF factor
• B. High, daily intermittent spiking fevers & rash
• C. Single joint involvement
• D. Painless joint involvement

Answer: (B)

Systemic-onset JIA (Still disease) is defined by a distinctive fever pattern: high, daily spikes that occur once or more per day, often lasting a few hours and then returning to baseline, typically accompanied by a transient salmon-pink rash during the febrile episodes. This daily, intermittent fever with rash is the hallmark that sets systemic-onset JIA apart from other JIA subtypes. The other features don’t fit as well. Positive RF is more characteristic of RF-positive polyarticular JIA or adult rheumatoid arthritis, while systemic-onset JIA is usually RF-negative. Involvement of a single joint points to oligoarticular or monoarticular arthritis rather than the systemic form, and painless joints are not typical in systemic-onset disease, where synovitis and inflammation tend to cause pain and swelling.

Systemic-onset JIA (Still disease) is defined by a distinctive fever pattern: high, daily spikes that occur once or more per day, often lasting a few hours and then returning to baseline, typically accompanied by a transient salmon-pink rash during the febrile episodes. This daily, intermittent fever with rash is the hallmark that sets systemic-onset JIA apart from other JIA subtypes.

The other features don’t fit as well. Positive RF is more characteristic of RF-positive polyarticular JIA or adult rheumatoid arthritis, while systemic-onset JIA is usually RF-negative. Involvement of a single joint points to oligoarticular or monoarticular arthritis rather than the systemic form, and painless joints are not typical in systemic-onset disease, where synovitis and inflammation tend to cause pain and swelling.