Vertebral (spinal osteomyelitis, spondylodiscitis, septic discitis, disc space infection)

[Clin Infect Dis 2015;61:e26-46]

Jump to Therapy

-In adults, vertebral osteomyelitis most common, occurring in lumbar, thoracic, cervical sites.

-May present acutely (evolving over days/weeks) or subacutely/chronic (weeks/months).

-Caused by:

• hematogenous seeding

• direct inoculation at time of surgery

• contiguous spread from adjacent soft tissue

- May result in concomitant paravertebral, epidural, or psoas abscess; increased risk of neurologic sequelae. Urgent neurosurgical consult required.

- Endocarditis diagnosed in up to one-third of cases of vertebral osteomyelitis.

- Patients with vertebral osteomyelitis due to MRSA, or with undrained paravertebral/psoas abscess, or end-stage renal disease may be at increased risk of recurrence [Clin Infect Dis 2016;62:1262-9].

Investigations:

• Blood cultures recommended. If positive, repeat blood cultures to ensure clearance of bacteremia.

• Radiologically-guided or open biopsy for culture and histopathology (higher yield than blood cultures) is recommended, except if blood cultures positive for S. aureus, S. lugdunensis, Enterobacterales, or Brucella species.

• CBC and differential, serum creatinine.

• ESR or CRP - low specificity for diagnosis but if initially elevated, may be useful to monitor response. Recommended at baseline and at 4 weeks. NB: These values may increase within the first few weeks despite clinical improvement.

• Imaging:

  • Spine MRI superior to CT scan for vertebral osteomyelitis and identification of epidural abscess. If MRI not available, alternative imaging includes spine gallium/Tc99 bone scan, CT or PET scan.

  • Bone scan may be falsely positive if recent trauma/aspiration of joint/superficial infection; gallium scan may improve specificity.

  • MRI abnormalities may persist long after successful treatment. Repeat MRI not needed unless lack of clinical response, suspected treatment failure, or presence of undrained abscess.

Indications for surgery:

• Progressive neurologic deficits

• Symptoms of spinal cord compression

• Spinal instability

• Progression or recurrence despite appropriate antimicrobial therapy

- For culture-directed therapy, see Recommended Therapy of Culture-Directed Infections: Treatment of Culture-proven Vertebral Osteomyelitis.

- Delay empiric therapy until microbiologic diagnosis is made unless patient is septic/ hemodynamically unstable, or has severe and/or progressive neurologic compromise.

- Surgical debridement and drainage of associated soft tissue abscesses recommended.

S. aureus/MRSA

Streptococcus spp
Enterococcus spp
Enterobacterales, including Salmonella spp
P. aeruginosa

M. tuberculosis (consult ID)
Brucella (if endemic risk)
Dimorphic fungi (if endemic risk) (consult ID)
Yeast (consult ID)

Coagulase negative Staphylococci
Cutibacterium (formerly Propionibacterium) acnes

If blood culture positive for Gram positive cocci in clusters