From the Guidelines
For septic arthritis and osteomyelitis, the empiric antibiotic of choice is vancomycin for both children and adults, especially when methicillin-resistant Staphylococcus aureus (MRSA) is suspected 1.
Key Considerations
- In children, clindamycin (10–13 mg/kg/dose IV every 6–8 h, not to exceed 40 mg/kg/day) can be used as empirical therapy if the clindamycin resistance rate is low 1.
- For adults, vancomycin (15–20 mg/kg/dose IV every 8–12 h) is recommended, with the addition of other antibiotics such as cefazolin or gentamicin based on the clinical scenario and suspected pathogens 1.
Treatment Duration
- The duration of treatment is typically 4-6 weeks for osteomyelitis and 2-4 weeks for septic arthritis 1.
Important Notes
- Surgical debridement and drainage of associated soft-tissue abscesses is the mainstay of therapy for osteomyelitis and should be performed whenever feasible 1.
- Drainage or debridement of the joint space should always be performed for septic arthritis 1.
From the Research
Empiric Antibiotic Therapy for Septic Arthritis and Osteomyelitis
The empiric antibiotic therapy for septic arthritis and osteomyelitis in children and adults is based on the most likely causative pathogens, patient age, immunization status, underlying disease, and other clinical and epidemiological considerations.
- The choice of empiric antimicrobial therapy should cover Staphylococcus aureus and common respiratory pathogens 2, 3, 4.
- For children aged over 3 months, empiric antibiotic treatment consists of a short intravenous cycle based on anti-staphylococcal penicillin or a cephalosporin, with the addition of gentamicin in infants aged under 3 months 2.
- For adults, antibiotic courses of 3 to 4 weeks in duration are usually adequate for uncomplicated bacterial arthritis, but treatment duration should be extended to 6 weeks if there is imaging evidence of accompanying osteomyelitis 5.
- The treatment can be safely switched to oral after 2-4 days, providing large doses of a well-absorbing antibiotic and, for time-dependent antibiotics, 4 times-a-day administration are used 4.
Special Considerations
- Methicillin-resistant Staphylococcus aureus (MRSA) has become a major cause of septic arthritis in the United States, and MRSA joint infection seems to be associated with worse outcomes 5.
- Treatment of neonates, patients with immunodeficiency, or cases caused by methicillin-resistant S. aureus may deserve a different approach 4.
- Kingella kingae and Salmonella are important pathogens only regionally, and empiric treatment should be adjusted accordingly 4.