From the Guidelines
Outpatient treatment of osteomyelitis should prioritize surgical debridement and drainage of associated soft-tissue abscesses, followed by a minimum 8-week course of antibiotic therapy, with options including IV vancomycin, daptomycin, or oral antibiotics such as linezolid, clindamycin, or trimethoprim-sulfamethoxazole, as recommended by the Infectious Diseases Society of America 1.
Key Considerations
- Surgical debridement is the mainstay of therapy and should be performed whenever feasible to remove infected or necrotic tissue and obtain cultures for targeted therapy 1.
- The optimal route of administration of antibiotic therapy has not been established, but parenteral, oral, or initial parenteral therapy followed by oral therapy may be used depending on individual patient circumstances 1.
- Antibiotic options include IV vancomycin, daptomycin, or oral antibiotics such as linezolid, clindamycin, or trimethoprim-sulfamethoxazole, with the addition of rifampin recommended by some experts 1.
Diagnostic Approach
- Magnetic resonance imaging (MRI) with gadolinium is the imaging modality of choice for detecting early osteomyelitis and associated soft-tissue disease 1.
- Erythrocyte sedimentation rate (ESR) and/or C-reactive protein (CRP) level may be helpful in guiding response to therapy 1.
- A definite diagnosis of bone infection usually requires positive results on both histological and microbiological examinations of an aseptically obtained bone sample 1.
Treatment Monitoring
- Regular follow-up with infectious disease specialists and orthopedic surgeons is essential to monitor treatment response and adjust therapy as needed.
- Outpatient parenteral antimicrobial therapy (OPAT) requires reliable IV access, regular laboratory monitoring, and weekly clinical assessments.
- Treatment success depends on identifying the causative organism, controlling any underlying conditions, ensuring adequate nutrition, and managing pain.
From the Research
Treatment Options for Osteomyelitis in an Outpatient Setting
- Systemic antimicrobial therapy is critical to the management of osteomyelitis, with the goal of achieving adequate drug levels at the site of infection 2.
- Outpatient parenteral therapy and the use of oral agents have simplified the delivery of long-term treatment regimens 2.
- Antibiotic selection should be based on the spectrum of action, with intravenous beta-lactams being the treatment of choice for methicillin-susceptible Staphylococcus aureus, and vancomycin being the treatment of choice for methicillin-resistant Staphylococcus aureus osteomyelitis 2.
- Oral fluoroquinolones and parenteral beta-lactam agents can be used for the treatment of gram-negative osteomyelitis, but increasing resistance has complicated management of these infections 2.
Antibiotic Regimens
- Ceftriaxone is an effective and safe agent for the treatment of osteomyelitis, with once-daily dosing making outpatient therapy feasible for most patients 3.
- Oral antibiotics, such as fluoroquinolones, can achieve adequate levels in bone and are a reasonable choice for osteomyelitis caused by susceptible organisms 4.
- The addition of adjunctive rifampin to other antibiotics may improve cure rates 4.
- Newer agents, such as ertapenem and daptomycin, are promising for the treatment of osteomyelitis due to resistant bacteria 5.
Duration of Therapy
- The optimal duration of therapy for chronic osteomyelitis remains uncertain, with no evidence that antibiotic therapy for more than 4-6 weeks improves outcomes compared to shorter regimens 4.
- Defining the optimal route and duration of antibiotic therapy and the role of surgical debridement in treating chronic osteomyelitis are important, unmet needs 4.