What is discospondylitis?
Discospondylitis, also called spondylodiscitis, is a bacterial or fungal infection of the intervertebral discs and intervertebral endplates of two adjacent vertebrae in dogs.
What causes discospondylitis?
Discospondylitis is an infectious disease which is most often of bacterial origin but which can, much more rarely, be caused by the presence of fungi. In the second case, we speak of a fungal infection.
The bacterial agents most often responsible for discospondylitis are Staphycoccus aureus (or Staphylococcus aureus), Escherichia coli, Streptococcus sp., Pasteurella sp. and Proteus sp As for fungi, these are most often Coccidioides immitis and Aspergillus sp
In the vast majority of cases, disconspondylitis comes from a primary infectious focus that has spread to the intervertebral disc by the hematogenous route (through the blood). Discospondylitis can thus be the complication of pneumonia, pyelonephritis, prostatitis, pyometra, deep pyoderma, endocarditis, pyothorax or even periodontitis.
Very rarely, contamination can occur directly, when bacteria or fungi are introduced directly into the intervertebral disc during a deep bite or a puncture wound.
It can also come from the migration of a contaminated foreign body to the animal's spinal cord, such as a spikelet for example. These foreign bodies can enter the body by inhalation, ingestion or through a penetrating wound.
Finally, brucellosis can also be complicated by discospondylitis.
Large dogs as well as whole males are more frequently affected by this condition, although it can occur in all dogs without exception.
Dogs affected by chronic skin infections or immunocompromised are also more exposed to the disease than others.
What are the symptoms of discospondylitis?
Signs of discospondylitis may consist of:
- spinal pain,
- locomotor disorders,
- lameness,
- neurological disorders (incontinence, paralysis) in the event of damage to the spinal cord and/or nerve roots.
Many affected dogs may also show non-specific signs such as decreased appetite, weight loss and chronic fever.
How is discospondylitis diagnosed?
Discospondylitis is notably diagnosed using x-rays of the spine. Although the disc itself is not visible on x-rays, the disease often causes osteolysis of the endplates and a reduction in the intervertebral space which can be seen on radiographs two to six weeks after the onset of the vertebral discs. first clinical signs.
In some cases, other imaging tests may be necessary such as myelography, MRI or CT scan, when X-rays are not sufficient.
If necessary, your veterinarian can perform additional tests to confirm the type of infection. These tests may include urine and blood tests.
In some cases, it is possible to obtain a culture directly from the primary infection site or from the infected disc by performing a biopsy.The latter procedure, performed under general anesthesia, is the most accurate way to diagnose discospondylitis and find out which microorganism is causing the infection. However, due to the cost and invasiveness of the procedure, this test is not always recommended or performed.
What are the treatments for discospondylitis?
Discospondylitis is treated with antibiotics or antifungals, depending on the type of infection. Treatment should be given for a period of at least 6 weeks. It can sometimes continue for several months. Stopping treatment prematurely could allow a resurgence of the infection.
In addition to these antibiotics, treatment for discospondylitis usually includes pain medication.
In case of spinal cord compression or if the dog's condition does not improve despite antibiotics, surgery may be necessary.