From the Guidelines
The recommended workup for suspected osteomyelitis includes a combination of clinical tests, laboratory tests, and imaging studies, with MRI being the gold standard for diagnosis, as recommended by the most recent guidelines 1. The workup should begin with a thorough clinical evaluation, including a probe-to-bone test for diabetic foot osteomyelitis, and laboratory tests such as complete blood count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) to assess for inflammatory markers 1. Blood cultures should be obtained before starting antibiotics to identify potential pathogens. Plain radiographs are the initial imaging study, though they may be normal early in the disease 1. Advanced imaging is essential, with MRI being the preferred modality due to its high sensitivity (90-100%) and ability to detect early bone marrow edema 1. Bone scans or CT scans may be alternatives when MRI is contraindicated. Definitive diagnosis requires bone biopsy with culture and histopathology, ideally obtained before antibiotic initiation, either intraoperatively or percutaneously 1. The workup should be thorough as accurate diagnosis guides appropriate antibiotic selection and duration, which typically ranges from 4-6 weeks depending on the causative organism, location, and extent of infection. Multidisciplinary management involving infectious disease specialists, orthopedic surgeons, and radiologists is recommended for optimal outcomes. Key considerations in the workup include:
- Clinical evaluation, including probe-to-bone test for diabetic foot osteomyelitis
- Laboratory tests, including complete blood count, ESR, and CRP
- Blood cultures before starting antibiotics
- Imaging studies, with MRI as the gold standard
- Bone biopsy with culture and histopathology for definitive diagnosis
- Multidisciplinary management for optimal outcomes.
From the Research
Recommended Workup for Suspected Osteomyelitis
The recommended workup for suspected osteomyelitis involves a combination of diagnostic tests and procedures to confirm the presence of infection and identify the causative pathogen.
- Definitive diagnosis of osteomyelitis usually requires microbial culture of bone specimens obtained either by surgery or by percutaneous needle biopsy 2.
- Imaging studies such as X-rays, CT scans, or MRI scans may be used to evaluate the extent of bone involvement and guide the biopsy procedure.
- Laboratory tests such as blood cultures and inflammatory marker tests (e.g., erythrocyte sedimentation rate, C-reactive protein) may be used to support the diagnosis and monitor the response to treatment.
Antibiotic Therapy
Antibiotic therapy is a critical component of the management of osteomyelitis.
- The choice of antibiotic regimen depends on the suspected or confirmed causative pathogen, as well as the patient's medical history and allergy profile 3, 4, 5, 6.
- Empiric antibiotic therapy may be initiated in seriously ill patients or those with negative microbiological results, with subsequent adjustment based on culture and susceptibility results 6.
- Commonly used antibiotic regimens for osteomyelitis include:
- Beta-lactams (e.g., penicillins, cephalosporins) for methicillin-susceptible Staphylococcus aureus 3, 4
- Vancomycin for methicillin-resistant Staphylococcus aureus 3, 6
- Fluoroquinolones or beta-lactam agents for gram-negative osteomyelitis 3, 4
- Combination therapy (e.g., vancomycin plus a broad-spectrum cephalosporin or fluoroquinolone) for complex or healthcare-associated infections 6
Surgical Intervention
Surgical intervention is often necessary to manage osteomyelitis, particularly in cases of chronic or complicated infection.
- Thorough debridement of infected bone and tissue is essential to reduce the bacterial load and promote healing 5, 2.
- Surgical procedures may also involve the use of antibiotic-impinging devices (e.g., beads, spacers, coated implants) to deliver local antibiotic therapy 5.
- Hyperbaric oxygen therapy may be used as an adjunctive treatment to enhance wound healing and reduce bacterial load 5.