Spinal epidural abscess due to coinfection of bacteria and tuberculosis: A case report

Abstract

Background: Spinal epidural abscess (SEA) is a rare condition that mostly results from infection with either bacteria or tuberculosis. However, coinfection with bacteria and tuberculosis is extremely rare, and it results in delays in diagnosis and antimicrobial treatment causing unfavorable outcomes.

Case summary: A 75-year-old female visited the hospital with low back pain, and magnetic resonance imaging (MRI) revealed an SEA at the lumbosacral segment. Staphylococcus hominis and methicillin-resistant Staphylococcus epidermidis were identified from preoperative blood culture and intraoperative abscess culture, respectively. Thus, the patient underwent treatment with vancomycin medication for 9 wk after surgical drainage of the SEA. However, the low back pain recurred 2 wk after vancomycin treatment. MRI revealed an aggravated SEA in the same area in addition to erosive destruction of vertebral bodies. Second surgery was performed for SEA removal and spinal instrumentation. The microbiological study and pathological examination confirmed Mycobacterium tuberculosis as the pathogen concurrent with the bacterial SEA. The patient improved completely after 12 mo of antitubercular medication.

Conclusion: We believe that the identification of a certain pathogen in SEAs does not exclude coinfection with other pathogens. Tubercular coinfection should be suspected if an SEA does not improve despite appropriate antibiotics for the identified pathogen.

Keywords: Bacteremia; Case report; Coinfection; Epidural abscess; Tuberculosis.

Figure 1

Initial spinal magnetic resonance imaging. A: Contrast-enhanced T1-weighted sagittal image shows an epidural abscess with spondylitis at the lumbosacral (L5-S1) segment; B: Contrast-enhanced T1-weighted axial image shows a significant amount of abscess in the spinal canal.

Figure 2

Follow-up spinal magnetic resonance imaging before second surgery. Contrast-enhanced T1-weighted sagittal image and an axial image show recurrence of the epidural abscess with spondylitis at the lumbosacral (L5-S1) segment. A: Contrast-enhanced T1-weighted sagittal image; B: Axial image.

Figure 3

Histopathological examination revealed chronic granulomatous inflammation with central necrosis (thick arrow) and multinucleated giant cells (thin arrow) (hematoxylin and eosin stain, magnification × 100).

Figure 4

Follow-up spinal computed tomography and simple X-ray images after second surgery. A: 1-wk postoperative spinal computed tomography shows bony erosion and autologous bone graft harvested from iliac crest (thick arrow); B: 1-wk postoperative simple X-rays; C: 3-year postoperative simple X-rays; D: 10-year postoperative simple X-rays. Ten-year postoperative simple X-ray revealed fracture of rod (thin arrow).