Research Update: Clinical features of spinal abscess in dogs

Spinal abscess, or epidural empyema, is an uncommonly described septic condition of the epidural space. Infection by hematogenous spread or local extension causes spinal pain, fever, and neurologic dysfunction. In this retrospective study from a university teaching hospital, the clinical characteristics and treatment outcomes of a spinal epidural abscess in seven dogs were described. Various breeds were represented, and the dogs ranged in age from 7 months to 13 years. The most common clinical signs were spinal pain, acute paraparesis or paraplegia, lethargy, and anorexia. All dogs had neurologic deficits, and four of five were febrile.

The most common complete blood count, urinalysis, and CSF analysis abnormalities were leukocytosis, neutrophilia, proteinuria, and elevated CSF protein concentrations and total cell counts. Myelography confirmed extradural spinal cord compression. Bacteria were not isolated from the CSF but from blood, the surgical site, urine, or pleural fluid. Escherichia coli, Bacteroides or Prevotella species, and Staphylococcus intermedius were the most common pathogens identified.

Dogs were treated with antibiotics and hemilaminectomy. Five dogs improved neurologically and had a good long-term outcome. One dog was euthanized because of neurologic deterioration and pleural effusion, and another dog had a cervical intervertebral disk herniation unrelated to the abscess one month after surgery and was euthanized. The authors concluded that early diagnosis and aggressive medical and surgical treatments would provide a successful outcome for this uncommon yet highly morbid condition.

COMMENTARY

The results of this study should alert clinicians to the possibility of this potentially grave lesion in dogs with the previously described clinical signs and diagnostic features. The authors noted that, when available, advanced imaging with magnetic resonance or computed tomography might provide better characterization of the lesion. It is interesting to note that bacteria were not isolated from the csf in these patients. Spinal cord decompression and appropriate antimicrobial therapy were apparently highly successful in resolving the condition in this small group of dogs.

Lavely JA, Vernau KM, Vernau W, et al. Spinal epidural empyema in seven dogs. Vet Surg 2006;35:176-185.

The information in "Research Updates" was provided by Veterinary Medicine Editorial Advisory Board member Joseph Harari, MS, DVM, DACVS, Veterinary Surgical Specialists, 21 E. Mission Ave., Spokane, WA 99202.

Joseph Harari, MS, DVM, DACVS