Key Points
- Native Vertebral Osteomyelitis (NVO) in adults is often the result of hematogenous seeding of the adjacent disc space from a distant focus, since the disc is avascular.
- NVO is commonly monomicrobial and most frequently due to Staphylococcus aureus.
- The diagnosis of NVO is often delayed and often initially managed as degenerative spine disease.
- NVO is typically diagnosed in the setting of recalcitrant back pain unresponsive to conservative measures and elevated systemic inflammatory markers with or without fever.
- The majority of patients are cured with a 6 week course of antimicrobial therapy, but some patients may need surgical debridement and/or spinal stabilization during or after a course of antimicrobial therapy.
Diagnosis
- Clinicians should suspect the diagnosis of NVO in patients with new or worsening back or neck pain and:
- Fever (S/L).
- Elevated ESR or CRP (S/L).
- Concomitant bloodstream infection or infective endocarditis (S/L).
- Clinicians may consider the diagnosis of NVO in patients who present with:
- Fever and new neurologic symptoms with or without back pain (W/L).
- New localized neck or back pain, following a recent episode of S. aureus bloodstream infection (W/L).
- IDSA recommends performing a pertinent medical and a motor/sensory neurologic examination in patients with suspected NVO (S/L).
- IDSA recommends obtaining bacterial (aerobic and anaerobic) blood cultures (two sets) and baseline ESR and CRP in all patients with suspected NVO (S/L).
- IDSA recommends a spine MRI in patients with suspected NVO (S/L).
- IDSA suggests a combination spine gallium/Tc99 bone scan, or Computerized Tomography (CT) scan or a Positron Emission Tomography (PET) scan in patients with suspected NVO when MRI cannot be obtained (e.g., implantable cardiac devices, cochlear implants, claustrophobia, or unavailability) (W/L).
- IDSA recommends obtaining blood cultures and serology tests for Brucella sp. in patients with subacute NVO residing in endemic areas for brucellosis (S/L).
- IDSA suggests obtaining fungal blood cultures in patients with suspected NVO and at risk for fungal infection (epidemiologic risk or host risk factors) (W/L).
- IDSA suggests performing a purified protein derivative (PPD) test or obtaining an interferon gamma release assay in patients with subacute NVO and at risk for Mycobacterium tuberculosis NVO (TB NVO) (i.e., originating or residing in endemic regions or having risk factors) (W/L).
- In patients with suspected NVO, evaluation by an infectious diseases specialist and a spine surgeon may be considered (W/L).
- IDSA recommends an image-guided aspiration biopsy in patients with suspected NVO (based on clinical, laboratory, and imaging studies) when a microbiologic diagnosis for a known associated organism (S. aureus, S. lugdunensis, and Brucella sp.) has not been established by blood cultures or serologic tests (S/L).
- IDSA advises against performing an image-guided aspiration biopsy in patients with S. aureus, S. lugdunensis or Brucella sp. bloodstream infection suspected of having NVO based on clinical, laboratory and imaging studies (S/L).
- IDSA advises against performing an image-guided aspiration biopsy in patients with suspected subacute NVO (high endemic setting) and strongly positive brucella serology (S/L).
- In patients with neurologic compromise with or without impending sepsis or hemodynamic instability, IDSA recommends immediate surgical intervention and initiation of empiric antimicrobial therapy (S/L).
- IDSA suggests the addition of fungal, mycobacterial, or brucella cultures on image-guided biopsy and aspiration specimens in patients with suspected NVO if epidemiologic, host risk factors, or characteristic radiologic clues are present (W/L).
- IDSA suggests the addition of fungal and mycobacterial cultures, and bacterial nucleic acid amplification test (NAAT) to appropriately stored specimens if aerobic and anaerobic bacterial cultures reveal no growth in patients with suspected NVO (W/L).
- If adequate tissue can be safely obtained, pathology specimens should be sent from all patients to help confirm a diagnosis of NVO and guide further diagnostic testing, especially in the setting of negative cultures (S/L).
- In the absence of concomitant bloodstream infection, IDSA recommends obtaining a second aspiration biopsy in patients with suspected NVO in whom the original image-guided aspiration biopsy specimen grew a skin contaminant [coagulase-negative staphylococci (except S. lugdunensis), Propionibacterium sp. or diphtheroids] (S/L).
- In patients with a non-diagnostic first image-guided aspiration biopsy and suspected NVO, further testing should be done to exclude difficult-to-grow organisms (e.g., anaerobes, fungi, Brucella sp. or mycobacteria) (S/L).
- In patients with suspected NVO and a non-diagnostic image-guided aspiration biopsy and laboratory work-up, IDSA suggests either repeating a second image-guided aspiration biopsy, a percutaneous endoscopic discectomy and drainage (PEDD), or proceeding with an open excisional biopsy (W/L).