Principles of diagnosis and management of acute nongonococcal septic arthritis

Indicators at presentation
    Recent onset of fever and malaise
    Local pain, warmth, swelling, and decreased range of motion in the involved joint
    The presence of any risk factors as determined by a detailed history
Diagnosis by synovial fluid testing
    Synovial culture and Gram stain
    Leukocyte counts in excess of 50,000/mm3
    Glucose level of <40 mg/dl or less than half that seen in the serum
    High concentration of lactate
    >90% polymorphonuclear leukocytes
    Lack of bifringent crystals (Note: simultaneous crystalline and bacterial arthritis has been reported)
Other laboratory indicators
    May have an elevated erythrocyte sedimentation rate, C-reactive protein levels, and/or peripheral leukocyte levels
    Sputum, urine, and blood cultures may be warranted; blood cultures are positive in 50% of cases
    Antibiotics adjusted based on culture and sensitivity results
    Adequate drainage of joint
        Needle aspiration
        Arthroscopic drainage
        Open drainage in difficult and deep joints
    Monitoring of synovial fluid leukocyte counts and cultures
    Acute phase of disease — patient rest and optimal joint position
    Following the acute phase — early physical therapy and aggressive mobilization