Review Question - QID 213123

The patient is presenting with discitis at L2-3 without evidence of neural compression from the infection, which necessitates full spine MRI imaging to determine the cause of the patient's neurologic changes.

Spinal epidural abscesses are the accumulation of purulence or granulation between the dural sac and the surrounding epidural fat. Surgical decompression is indicated if there are neurological deficits, instability, or persistent infection despite medical therapy. In general, IV antibiotics are the first line of treatment for neurologically intact patients with a small abscess and no signs of cord compression.

Ju et al. performed a retrospective case-control study of patients presenting with single epidural abscesses and skip epidural abscesses in the spine. Factors associated with skip lesions were delayed presentation (>7 days of symptoms), concomitant area of infection outside of the spine, and an ESR >95 mm/hr on presentation. The probability of having a skip epidural abscess was 73% with all three factors, 13% with two factors, and 2% with one factor. The authors concluded that patients presenting with a higher risk of skip epidural abscesses based on these factors can benefit from imaging of the entire spine.

Patel et al. performed a retrospective study of risk factors associated with failed medical treatment for a spinal epidural abscess. They found that outcomes after delayed surgical treatment due to failed medical therapy were associated with a worse neurological status. They reported that medical treatment failure was associated with diabetes mellitus, a CRP level >115 mg/L, a WBC count >12.5K cells/mL, and positive blood cultures. The presence of three or more parameters conferred a 76.9% failure rate. The authors concluded that patients presenting with these parameters may benefit from early surgical treatment in order to achieve better neurological outcomes.

Arko et al. performed a systematic review of the literature regarding medical and surgical treatment of spinal epidural abscesses. They found that the literature pointed to an increasing number of patients being treated surgically (60%) compared to historical data. Patients that were treated medically and that subsequently required surgical decompression were more likely to have diabetes, a CRP > 115 mg/L, a WBC count >12K cells/mL, positive blood cultures, be aged older than 65 years, have MRSA, and have advanced neurological deficits.

Figure A is a sagittal T2 MRI of the lumbar spine with discitis at L2-3 with erosive changes of the endplate. There is additionally degenerative changes with L4-5 spondylolisthesis.

Incorrect Answers:
Answer 1: Treatment with IV antibiotics is warranted when discitis or an epidural abscess if found without neurological deficits and is small on imaging.
Answer 2: CT-guided aspiration of the L2-3 disc space would be appropriate to find the causative organism, but in this case, the lumbar spine lesion does not explain the patient's neurologic findings.
Answer 3: Surgical debridement and interbody fusion would be the correct option if she was experiencing neurologic changes from the discitis at L2-3.
Answer 4: Surgical treatment of the L4-5 spondylolisthesis is not appropriate at this time.