A 32-year-old intravenous drug user presents with 3 days of severe thoracic back pain and fever. Over the next 12 hours he develops progressive bilateral leg weakness and urinary retention. Examination shows reduced power below T10 with sensory level. Which single investigation should be performed immediately?
- A CT myelography
- B MRI of the spine with gadolinium ✓
- C Lumbar puncture
- D Technetium-99m bone scintigraphy
Correct answer: B. MRI of the spine with gadolinium
Explanation
The rapid progression of back pain, fever, and ascending neurological deficit with sphincter disturbance in an injecting drug user indicates spinal epidural abscess, most often due to Staphylococcus aureus. Urgent gadolinium-enhanced MRI is the diagnostic test of choice and must precede decompression. Lumbar puncture risks seeding infection into the subarachnoid space and is contraindicated over a suspected abscess level.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.