Patient selection: 1-18 years of age with septic arthritis
Adjacent infections include: intramuscular abscess, subperiosteal abscess, pyomyositis, osteomyelitis
Parameters:
(1) age in years
(2) C-reactive protein (CRP) in mg/L
(3) number of days with symptoms (fever, joint effusion, impaired weightbearing)
(4) platelet count per microliter
(5) absolute neutrophil count per microliter
|
Parameter
|
Finding
|
Points
|
|
age in years
|
<= 4 years
|
0
|
|
|
> 4 years
|
1
|
|
CRP
|
<= 8.9 mg/L
|
0
|
|
|
> 8.9 mg/L
|
1
|
|
number of days with symptoms
|
<= 3 days
|
0
|
|
|
> 3 days
|
1
|
|
platelet count
|
>= 310,000 per µL
|
0
|
|
|
< 310,000 per µL
|
1
|
|
absolute neutrophil count
|
<= 7,200 per µL
|
0
|
|
|
> 7,200 per µL
|
1
|
total score =
= SUM(points for all 5 parameters)
Interpretation:
• minimum score: 0
• maximum score: 5
• A score >= 3 was associated with increased risk for infection adjacent to a septic joint.
Performance:
• The sensitivity of a score >= 3 was 90% with a specificity of 67%. The authors claim an area under the ROC curve of 0.89.
• A score of >= 4 was 100% sensitive for septic arthritis.
