Overview
A spinal epidural abscess describes a collection of pus within the epidural space (the area between the dura mater and vertebral wall). This may occur due to:
- Spread from adjacent structures (e.g. discitis)
- Haematogenous spread (e.g. bacteraemia in infective endocarditis)
- Direct infection (e.g. surgery to the spine)
- Immunosuppression (e.g. HIV, chemotherapy, diabetes mellitus)
The most common causative organism is Staphylococcus aureus
Features
- Fever
- Back pain
- Focal neurological deficits that correlate with the region of the spinal cord affected
Investigations
- Blood cultures:
- Identifies causative organism
- Ideally should be taken before antibiotic therapy, provided this does not delay treatment
- Full blood count (FBC):
- May show leukocytosis
- C-reactive protein (CRP), erythrocyte sedimentation rate (ESR):
- Non-specific markers of inflammation
- May be elevated
- MRI spine with and without IV contrast:
- Shows epidural abscess
- The whole spine should be imaged as there may be ‘skip lesions‘ (intermittent affected and unaffected regions)
Management
Initial management involves broad-spectrum antibiotics which are then narrowed down based on culture results.
