Thoracic spinal epidural abscess with progressive cord compression
A 58-year-old man with type 2 diabetes mellitus presents with 5 days of fever, severe mid-back pain, and progressive leg weakness. He now has bilateral hip flexor power of 2/5, urinary retention, and a sensory level at T9. Temperature is 38.8°C, white cell count 15.2 × 10⁹/L, and C-reactive protein 220 mg/L. MRI shows a posterior epidural collection from T8 to T10, 9 mm in maximal thickness, with cord compression and signal change in the cord, plus discitis and endplate oedema at T9–T10. Blood cultures have been drawn but results are pending. He is haemodynamically stable and can lie flat. The hospital has no interventional radiology service overnight, but a spinal surgeon and CT scanner are available.
1. Would you start antibiotics before cultures and before decompression? Justify the timing and choice.
Read the worked answer
Draw two sets of blood cultures before antibiotics if this can be done within minutes, but do not delay antibiotics for culture results or for surgery. In a patient with fever, raised inflammatory markers, and progressive cord compression, start empiric intravenous antibiotics after cultures are drawn. Cover staphylococci, including methicillin-resistant Staphylococcus aureus, and gram-negative organisms; a typical regimen is vancomycin plus a third- or fourth-generation cephalosporin, adjusted to local resistance patterns and renal function. Antibiotics alone are not sufficient here because there is a neurological deficit and cord signal change. The key judgement is that antibiotics reduce bacteraemia and surgical contamination but do not decompress the cord. Take intraoperative cultures and disc material for microbiology and histology because blood cultures may be negative. Do not give steroids, which can worsen infection and do not improve cord compression in this setting. Involve infectious diseases early.
2. What is the role of surgery versus image-guided aspiration, and when would you operate? What approach would you choose?
Read the worked answer
Operate urgently, within 24 hours, because the patient has progressive weakness, urinary retention, and cord signal change. The goal is decompression, drainage of pus, and tissue diagnosis. A posterior laminectomy at T8–T10 with evacuation of the epidural collection is appropriate; if the discitis is anterior and causing significant destruction, a costotransversectomy or lateral approach may be needed, but the epidural collection here is posterior. Obtain pus and disc for culture. Do not place instrumentation routinely in the presence of active infection unless instability is present; if instability is likely, discuss a staged or instrumented approach with the spine team. Image-guided aspiration is an alternative for patients who are poor surgical candidates or who have no neurological deficit, but it is less reliable for thick collections and does not decompress the cord. The presence of neurological deficit makes surgery the priority. Start antibiotics before or during surgery and continue post-operatively.
3. Outline the post-operative antibiotic plan, follow-up imaging, and rehabilitation. What would make you change the plan?
Read the worked answer
Continue intravenous antibiotics for 6–8 weeks for discitis with epidural abscess, guided by cultures and infectious diseases. If cultures are negative, cover staphylococci and gram-negative organisms and reassess at 2 weeks. Monitor white cell count, C-reactive protein, renal function, and neurological status. Repeat MRI at about 4–6 weeks, or sooner if symptoms worsen, to assess resolution of the collection and discitis. Do not expect complete radiological normalization at the end of antibiotics; improvement in enhancement and oedema is enough. Rehabilitation should start early with physiotherapy, bladder management, and pressure-area care. Change the plan if cultures identify a resistant organism, if the patient develops new fever or neurological deterioration suggesting inadequate drainage or a new collection, or if there is mechanical instability requiring stabilization. Consider oral step-down therapy only after a clear clinical response and with infectious diseases agreement.