Epidural abscess

Overview

• A spinal epidural abscess threatens the spinal cord or cauda equina by compression and also by vascular compromise(septic thrombophlebitis/vasculitis)

• If untreated, an expanding suppurative infection in the spinal epidural space impinges on the spinal cord, producing sensory symptoms and signs, motor dysfunction, and, ultimately, paralysis and death.

Risk factors

• diabetes mellitus• Spinal trauma/surgery • intravenous drug abuse• alcoholism• renal insufficiency• immunosuppression (including infection,

steroid use, cirrhosis, and malignancy), • pregnancy

Pathophysiology

• Direct extension (vertebral osteomyelitis, psoas abscess, or contiguous soft-tissue infection) – 10 to 30%

• Hematogenous spread – 50%• Instrumentation (surgery/epidural

anaesthesia) – 15-22%• Unknown cause – up to 30%

Epidemiology

• Incidence of 2.8 per 10000 admission in the us• Equal sex ratio• Average age of older than 50yo

Presentation

• Localised spinal pain• Radicular pain and numbness• Muscular weakness• Sphincter dysfunction• Paralysis• Fever• Pulmonary tuberculosis contact (esp in our setting)• Might have other source of infection prior to the

disease progression

Presentation

• Depends on virulence of organism– Pyogenic might have faster progression– Abscess from om or discitis may evolve slowly

over weeks/months• Clinical triad of fever, back pain and neurologic

deficit and is not present in most patients• Early presentation may be non specific with

chest pain and abdominal pain which are misleadings

Physical exmination

• Spinal examination for spinal tenderness and any deformities

• Need to do a complete neurology examination• Tone, power, reflexes, sensory, balbinski• Per rectal examination and bulbocavernousus

reflex

Investigation

• FBC to look for white cell count• ESR to look for elevation suggestive of

infection/inflammation• CRP more of acute infection• Blood culture and sensitirvity• Tuberculosis work out– Mantoux– Chest x ray– Sputum AFB

Imaging study

• CT scan may demonstrate fluid collection in the epidural space if mri not available

• MRI has the greatest diagnostic process– Sensitivity 90-95– Specificity >90

• MRI. T2-weighted image (A) and T1-weighted fat-saturated image after intravenous gadolinium (B), showing spondylodiscitis (arrow) complicated by an SEA at the C6–7 level (arrowheads).

Treatment

• Antibiotics • Urgent decompressive maninectomy need to

be done esp with patient of neurological deficit