Neonates
Do not appear ill
Only 50% have fever
Older infants, toddlers, children
Fever (>101.3), localizing signs
Labs
CRP >20
WBC >12K
Do not appear ill
Only 50% have fever
Fever (>101.3), localizing signs
CRP >20
WBC >12K
Septic arthritis 
Trauma
Monoarticular arthritis
Septic arthritis
Reactive arthritis
Acute Rheumatic Fever
Septic bursitis
Reactive Arthritis 