| Introduction |
- Although once the most common cause of childhood arthritis, it is now rare
- may follow untreated group A beta-hemolytic strep infections (2-6 wk latent period)
- Characterized by migratory arthritis that involves multiple large joints
- Systemic manifestations
- carditis
- erythema marginatum (painless macules usually on abdomen, but never on the face)
- subcutaneous nodules (on upper extremity extensor surfaces)
- chorea
- Diagnosis based on Jones criteria
- preceding strep infection with 2 major criteria or 1 major criteria and 2 minor criteria
- major criteria
- carditis
- polyarthralgia
- chorea
- erythema marginatum
- subcutaneous nodules
- minor criteria
- fever
- arthralgia
- prior rhematic fever
- increased ESR
- prolonged PR interval
|
| Presentation |
- Symptoms
- extremely painful joints; usually knees and ankles
- Physical exam
- red and tender joints with effusions
|
| Imaging |
|
|
| Labs |
- Antistreptolysin O titers elevated in 80%
- Synovial Fluid Analysis
| Condition | WBC (cells/mL) | PMNs (%) |
| Normal |
<200 |
<25% |
| Effusion from trauma |
<5,000 |
<25% |
| Toxic synovitis |
5,000-15,000 |
<25% |
| Acute rheumatic fever |
10,000-15,000 |
50%
|
| JRA |
15,000-80,000 |
75% |
| Septic arthritis |
>50,000 |
>75% |
|
| Treatment |
- Nonoperative
- treatment includes penicillin (250,000 U orally BID) and salicylates
|
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