Spinal epidural abscess
Spinal epidural abscess is a suppurative infection of the spinal epidural space, most often hematogenous Staphylococcus aureus, presenting with fever, focal spinal pain, and, if missed, progressive weakness. The diagnosis is established by emergent MRI with contrast. Treatment is empiric intravenous vancomycin plus ceftriaxone or cefepime, with emergent surgical decompression whenever a neurologic deficit is present.
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What this article covers
- Overview
Spinal epidural abscess is a suppurative collection of pus between the dura mater and the vertebral column, most often caused by Staphylococcus aureus reaching the epidural fat by hematogenous spread.
- Epidemiology
Rare but growing: no population incidence is established; the typical patient is middle-aged rather than elderly or pediatric, and exposures such as injection drug use and long-term vascular access…
- Risk factors
Injection drug use: repeated bacteremic episodes and, with skin-popping, direct soft-tissue seeding add to both incidence and recurrence risk.
- Pathophysiology
Bacteria reach the epidural space by one of three routes: hematogenous seeding of the vascular epidural fat from a distant focus, contiguous extension from vertebral osteomyelitis or discitis, or direct inoculation during a spinal procedure.
- Clinical features
Time course: severe, localized spinal pain develops first, over days to weeks, then radicular pain, then motor and sensory deficits, then bowel or bladder dysfunction; the interval from first pain to deficit can be as short as days.
- Differential diagnosis
Cauda equina syndrome from disc herniation: shares saddle anesthesia and bladder dysfunction, but there is no fever or focal tenderness, and MRI shows a herniated disc, not an enhancing epidural collection.
- Diagnosis
What establishes the diagnosis: the criteria are microbiologic and anatomic together, a positive blood culture or culture of pus from aspiration or surgical drainage, plus a rim-enhancing epidural…
- Management
First, obtain cultures, then treat: if the patient is stable, draw blood cultures before the first antibiotic dose below so empiric coverage can later be narrowed; if the patient is septic or has any…
- Complications
Permanent paralysis: irreversible weakness, sensory loss, or bowel and bladder dysfunction can result when decompression is delayed after a deficit appears, because the ischemic component of cord injury is often permanent.
- Prognosis
Outcome tracks time to decompression: the duration and severity of deficit before surgery is the strongest predictor of recovery, so even a short delay after paralysis develops sharply cuts the chance of recovery.
- Prevention
Sterile technique for spinal procedures: strict asepsis during epidural catheter placement, spinal injection, and spine surgery limits direct inoculation, the dominant nosocomial mechanism.
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Related articles
- Cauda equina syndrome
Cauda equina syndrome is compression of the lumbosacral nerve roots below the spinal cord causing saddle anesthesia, bladder or bowel dysfunction, bilateral leg weakness with areflexia, and low tone, most often from a large central lumbar disk herniation. It is a surgical emergency diagnosed by emergent MRI of the lumbar spine and treated with urgent decompression.
- Epidural hematoma
Epidural hematoma is an arterial bleed, classically from the middle meningeal artery after a temporal bone fracture, that collects between the skull and dura in a biconvex shape that does not cross suture lines; a lucid interval followed by rapid decline is classic, and a GCS below 9, anisocoria, or hematoma over 30 mL requires urgent surgical evacuation.
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Osteomyelitis is bone infection from hematogenous seeding or contiguous spread, most often from Staphylococcus aureus, presenting as subacute pain with or without a draining sinus tract and confirmed by bone biopsy culture. Empiric antibiotics are withheld until biopsy in a stable patient, and treatment combines source control with 4 to 6 weeks of culture-directed antibiotics, extended to 6 weeks or indefinite suppression for hardware-associated or chronic disease.
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