Chronic spinal epidural abscess in a cat: a case report with an unusual imaging finding

Spinal decompression and stabilisation in a cat with lumbar vertebral pathological fracture and subluxation, following discospondylitis and spinal epidural empyema

Case series summary

A 1-year-old castrated male Maine Coon cat was referred because of a 1-week history of progressive spastic non-ambulatory paraparesis. An MRI examination of the thoracolumbar spine showed multiple lytic lesions, with the most aggressive one centred on the adjacent endplates of L1-L2 and its associated disc. Ventral new bone formation, L1 vertebral body shortening and mild dorsal displacement of the caudal aspect of L1 were noted. Contrast enhancement of both paravertebral soft tissue and extradural lesion was present. These findings were compatible with L1-L2 discospondylitis (DS), spinal epidural empyema (SEE), with secondary L1 pathological vertebral fracture, subluxation and spinal cord compression. CT of the thoracolumbar spine, abdomen and thorax confirmed these findings. The patient deteriorated to paraplegia with absent nociception, despite initial medical therapy. A right-sided L1-L2 hemilaminectomy and spinal decompression were then performed, followed by application of a unilateral construct comprising four smooth arthrodesis wires and polymethylmethacrylate (PMMA). Staphylococcus aureus was isolated from both epidural material, intraoperatively sampled and blood culture. Antibiotic therapy was continued for 6 weeks, based on susceptibility results. The outcome was excellent, with a gradual improvement and complete neurological recovery at the 8-week postoperative check. Repeated spinal radiographs showed an intact apparatus and marked signs of vertebral fusion. At the 14-month follow-up examination, the cat remained free of clinical signs.

Relevance and novel information

To the authors' knowledge, this is the first case report of SEE and DS in a cat that required surgical stabilisation. The outcome was still optimal, despite the rapid neurological deterioration.

Spinal epidural empyema concurrent with sequestrum in a cat: a case report

A 5-month-old intact female mixed cat presented with repetitive paraplegia and drainage of pus from the back despite continuous antibiotic medication. Neurologic examination was consistent with below T3-L3 myelopathy. Computed tomography and magnetic resonance imaging revealed a contrast-enhanced mass in the L1-3 spinal canal, and bone fragments in the T13 and L1 spinal canal. Spinal epidural empyema was suspected, and hemilaminectomy was performed for T12-L2 on the right side and T11-12 on the left side. Bone fragments were diagnosed as sequestrum infected with Bacteroides.sp. The cat recovered enough to ambulate next day. One month after surgery, there was no deficit in neurological function. This is the first report of spinal epidural empyema concurrent with sequestrum in a cat.