Case Studies
 

Diskospondylitis and Epidural Abscess in an 8-Year Old Labrador Mix.

Diskospondylitis and Epidural Abscess

VETERINARIAN SPECIALTY CASE STUDY

Diskospondylitis is an infection that occurs within the disks and adjacent vertebrae of the back. Epidural abscess of the spinal column is a rare complication that can be fatal if left untreated.

By Stacey Sullivan, DVM
Diplomate American College of Veterinary Internal Medicine (Neurology)

1. Referral

Tanner, an 8-year-old MN Labrador mix, was referred to the Animal Specialty Group by Dr. Nicoleta Popescu of Media City Animal Hospital for a 1 week history of non-weight-bearing lameness of the right pelvic limb. He was evaluated by ASG’s surgery service.

2. Examination

Right hip pain was noted, along with marked lumbosacral pain but no neurologic deficits. Referral radiographs revealed spondylosis at L7-S1. Tanner was transferred to the neurology service and an MRI of the lumbosacral spine was performed.

3. Diagnostics

Referral CBC and chemistry were normal. Lumbar MRI revealed diskospondylitis at L7-S1, with an epidural abscess extending from L4-L6.

4. Diagnosis

Diskospondylitis and epidural abscess.

5. Treatment

A hemilaminectomy was performed from L4-6 and a dorsal laminectomy was performed from L6-S1. Histopathology of epidural fat revealed neutrophilic inflammation with intracellular bacteria. Culture of material from the epidural space yielded heavy growth of two Staphylococcus spp. The purulent material was removed from the spinal canal. Urine and blood cultures revealed growth of the same Staphylococcus spp organisms. On all cultures, the bacteria were sensitive to enrofloxacin.

6. Discussion

Diskospondylitis is most commonly a bacterial infection of the disc space, although fungal infection can occur. Typically, diskospondylitis occurs secondary to bacteremia which is a sequelea of infection elsewhere in the body. Most dogs with diskospondylitis do not experience an illness in which they appear septicemic; perhaps if they did, the infection would be treated before diskospondylitis could occur. The most common site of “occult” bacterial infection is the urinary tract.

Epidural abscess is a rare complication of diskospondylitis, but in this case gave us a clear reason to enter the spinal canal to obtain samples for culture so that an etiologic diagnosis could be made. In the absence of culturable-material other than urine, blood cultures can be useful. If the same organism is grown from blood and urine cultures, it is likely that organism is the cause of the patient’s diskospondylitis. If blood and urine cultures are negative, fungal and Brucella titers are the next diagnostic step. In the absence of positive culture results, an antibiotic trial may be a rational diagnostic tool. Because of the high incidence of Staph spp diskospondylitis in dogs, its reasonable to start with an antibiotic effective against Staph. Since treatment course will be likely be many months, this author usually starts with cephalexin because of its effectiveness against Staph and cost-effectiveness.

7. Recovery

Post-op, Tanner was inappetant and difficult to medicate. After several weeks, he had lost a precipitous amount of weight and a gastrotomy tube was placed.

With G-tube feedings and medication administration, Tanner did very well, returning to his normal weight. He was treated for 6 months with enrofloxacin and the infection resolved. By 1 month post-op, radiographic evidence of diskospondylitis was evident and treatment was continued two months beyond radiographic resolution. Pain was managed long-term with various NSAIDs and pain medications (tramadol initially and then gabapentin) and eventually accupuncture through our Physical Rehabilitation service.


Image of labrador is not “Tanner.”

Animal Specialty Group

DVM, Diplomate American College of Veterinary Internal Medicine (Neurology)

Dr. Stacey Sullivan received her Doctor of Veterinary Medicine degree from North Carolina State University in 1993. She moved to Auburn University for her internship, followed by a residency in neurology and neurosurgery at the University of Georgia.