Pathognomonic Feature of Neurobrucellosis
The pathognomonic feature of neurobrucellosis is vertebral body collapse, particularly affecting the lumbar spine, with L4 being commonly involved. 1
Clinical Presentation and Diagnosis
Neurobrucellosis is a serious complication of brucellosis, a zoonotic infection caused by bacteria of the genus Brucella. When it affects the spine, it can lead to:
- Vertebral body collapse (pathognomonic finding)
- Meningitis or meningoencephalitis
- Radiculopathy with sensory and motor deficits
- Back pain with possible radicular symptoms
Diagnostic Criteria
The diagnosis of neurobrucellosis requires:
- Clinical signs and symptoms suggestive of neurobrucellosis
- Positive serology for Brucella (titers ≥1:160 in endemic areas)
- Cerebrospinal fluid (CSF) abnormalities:
- Lymphocytosis
- High protein levels
- Low glucose levels
- Positive Brucella antibodies in CSF
Laboratory Testing
- Blood cultures (sensitivity 15-70%)
- Brucella tube agglutination test (Wright test) with titers ≥1:160 in endemic areas 2
- In non-endemic areas, ELISA screening followed by confirmatory agglutination test 3
Imaging
MRI is the preferred imaging modality for neurobrucellosis affecting the spine, showing:
- Vertebral body collapse (pathognomonic)
- Disc space involvement
- Possible epidural abscess formation
Treatment Approach
Antimicrobial Therapy
For neurobrucellosis, the recommended regimen includes:
First-line regimen: Doxycycline 100 mg twice daily for 3-6 months plus rifampicin 600-900 mg daily for 3-6 months, with streptomycin 15 mg/kg daily intramuscularly for the first 2-3 weeks 2
Alternative regimen: Doxycycline plus rifampicin with ceftriaxone instead of streptomycin (preferred for neurobrucellosis due to better CSF penetration) 4
Duration of Treatment
- Treatment should continue for 3-6 months for neurobrucellosis with vertebral involvement 2
- Monitoring of clinical response and serological titers is essential
Surgical Management
Surgical intervention is indicated in cases of:
- Spinal cord compression
- Significant vertebral collapse causing instability
- Abscess formation requiring drainage
- Failure of medical treatment 2
The typical surgical approach involves:
- Neural tissue decompression
- Posterior short segment transpedicular screw fixation and stabilization 1
Follow-Up and Prognosis
- Regular clinical and serological follow-up for at least 2 years after treatment 2
- Monitor for relapse, particularly in patients treated with regimens other than doxycycline-streptomycin
- Long-term sequelae may include limitation of movement and chronic pain
Prevention
- Pasteurization of dairy products
- Vaccination of livestock
- Use of personal protective equipment when handling potentially infected animals
- Public education about risks of consuming unpasteurized dairy products
Important Considerations
- In endemic areas, image-guided aspiration biopsy may not be necessary if blood cultures are positive for Brucella or if serology is strongly positive 3
- In non-endemic areas, evaluation by an infectious disease specialist and a spine surgeon is recommended 3
- Streptomycin use may be limited by its poor CSF penetration and potential neurotoxicity 4
Remember that early diagnosis and appropriate treatment are crucial to prevent permanent neurological complications from vertebral collapse in neurobrucellosis.