spine
Pyogenic Spinal Infection
advanced
6 min
28 marks
6 questions
Clinical Scenario
A 55-year-old male with type 2 diabetes presents with 3 weeks of progressive back pain, fever, and malaise. He has been treated for a urinary tract infection recently. His temperature is 38.5°C, WBC 18,000, CRP 180. On examination, he has severe tenderness over the lumbar spine and has developed leg weakness over the past 48 hours.
Sagittal T2-weighted MRI demonstrating L3-4 disc space infection with high signal in the disc and adjacent vertebral endplates. There is destruction of the L3 and L4 endplates with collapse. A posterior epidural abscess extends from L2 to L5 with cord/cauda compression. Paravertebral collection is visible anteriorly. This represents pyogenic spondylodiscitis with epidural abscess requiring urgent surgical debridement.
Image source: Open Access medical literature (NIH/PubMed Central) • CC-BY License
Questions
Question 1 (4 marks)
Describe the MRI findings and what is the most likely diagnosis?
Question 2 (5 marks)
What are the risk factors and common causative organisms?
Question 3 (6 marks)
How do you investigate this patient and what are the indications for surgery?
Question 4 (5 marks)
Describe your surgical approach for debridement and stabilization.
Question 5 (4 marks)
What is the antibiotic management strategy?
Question 6 (4 marks)
What are the expected outcomes and prognostic factors?
Exam Day Cheat Sheet
Must Mention
- •S. aureus most common (50-60%)
- •Blood cultures x2 BEFORE antibiotics
- •MRI = investigation of choice
- •Epidural abscess + neuro deficit = urgent surgery
- •6 weeks IV minimum, 6-12 weeks total
- •Titanium instrumentation OK with debridement
- •CRP to monitor response
Common Pitfalls
- •Antibiotics before cultures
- •Missing epidural abscess urgency
- •Short antibiotic course
- •Not checking echo for endocarditis
- •Avoiding needed instrumentation
- •Missing TB in appropriate populations