II. Causes
- Staphylococcus aureus (most common cause)
- Streptococcus Pneumoniae
- Salmonella
III. Labs
-
Synovial Fluid (obtain in all suspected cases)
- Normal Synovial Fluid Cell Count in >50% of Septic Arthritis cases
- Gram Stain Test Sensitivity is only 50% (high False Negative Rate)
- Synovial Fluid is the gold standard for diagnosis
IV. Management
- Obtain Synovial Fluid culture and start empiric Antibiotics
- Total Antibiotic course: 6 weeks
- Initial empiric management
- Cephaloporin sensitive
- Ceftriaxone 50-75 mg/kg up to 2 g/dose OR
- Ceftriaxone 75-100 mg/kg in high S. Pneumoniae resistance regions
- Cephalosporin resistance
- Clindamycin 10-15 mg/kg/dose (preferred) OR
- Vancomycin 15 mg/kg/dose (if systemic Sepsis or Clindamycin reactions)
- Cephaloporin sensitive
V. References
- Welsh and Welsh (2016) Crit Dec Emerg Med 30(11): 15-23