Epidemiology


Etiology


  • Staphylococcus aureus
    • Most common in adults and children > 2 years
    • Frequently found in patients with arthritis following invasive joint procedures
  • Streptococci
  • N. gonorrheae
    • Most common in sexually active young adults
  • Gram-negative rods esp. E. coli and P. aeruginosa

Pathophysiology


Clinical features


Diagnostics


Treatment


  • Emergent Management
    • This is an orthopedic emergency requiring immediate action to prevent joint destruction.
    • Two priorities: Joint Drainage & IV Antibiotics.
    • ALWAYS aspirate the joint (arthrocentesis) before giving antibiotics.
  • Empiric IV Antibiotics (Start immediately after aspiration)
    • General/Gram (+) cocci: Vancomycin (to cover MRSA, the most common cause).
    • Sexually Active Young Adult: Ceftriaxone (for N. gonorrhoeae). Also treat for Chlamydia.
    • Gram (-) Rods / Immunocompromised: Vancomycin + Anti-pseudomonal (e.g., Cefepime, Ceftazidime).
    • Gram Stain Negative: Vancomycin + Ceftriaxone.
  • Joint Drainage
    • Serial Needle Aspiration: May be sufficient for easily accessible joints (e.g., knee).
    • Surgical Washout (Arthroscopy or Arthrotomy): Required for hip joint, failure of needle aspiration, or thick purulence.
  • Duration of Therapy
    • Nongonococcal: ~3-4 weeks total. Start with IV and can switch to oral agents when improving.
    • Gonococcal: Shorter course of ~7-14 days.