A Case A Week for Veterinarians: Solution for case 19

Lateral view: New bone formation on ventral aspect of T13, L1, L2 and L3. Intervertebral disc (IVD) space between T13 - L1 and between L3 - L4 is reduced. Osteolytic lesions on the ventral aspect of L3.
VD View: Bone proliferation on the lateral aspect of T13-L1 and L1- L2 and L2 - L3. Reduced intervertebral space between L3-L4.

Tentative Diagnosis: Diskospondylitis.

Differentials: IVD protrusion, Vertebral fractures or luxation, Focal meningomyelitis, Vertebral neoplasia, Spondylosis deformans

Further diagnostic tests:
Myelogram, urinalysis, urine culture and sensitivity, brucellosis test (serology), blood culture for aerobes, anarobes and fungus, CSF analysis.
Urine and blood culture reports showed the Staphylococus spp sensitive to cephalexin. Brucellosis test was negative. CSF tap and myelogram was not performed in this case.

Common infectious agent found in diskospondylitis lesions:
Bacterial: Staphylococcus aureus and Staphylococcus intermedius are most commonly isolated. Other bacteria include Brucella canis, Streptococcus spp, Corynebacterium spp, Escherichia coli, Proteus spp, Pasteurella spp, and Bactericides spp.
Brucella is common in intact males. So unlikely in this case.
Fungal: Aspergillus spp and Coccidioides immitis
Focal meningomyelitis is still possible and a CSF analysis is needed to differentiate.

Intervertebral disk protrusion may cause similar clinical signs but can be differentiated on the basis of radiography and myelography. The lesion seen on radiographs was not consistent with intervertebral disk protrusion.
Vertebral fracture/luxation was not detected on radiographs.

Vertebral neoplasia usually does not affect adjacent vertebral end-plates. This is unlikely in this case due to adjacent vertebral end-plates being involved.

Spondylosis deformans rarely causes lysis of the vertebral endplates.

Treatment plan

Cephalexin 1000mg BID PO for 6 weeks.

Tramadol 50mg 1 capsule BID PO for 5 days.Taper to 50mg SID for another 5 days to gauge the effectiveness of antibiotic therapy.

Recheck after 5days of therapy. If improvement is seen do clinical revaluation every 2 wks and radiographs every 2-4 wks.

If no improvement change the antibiotics and reassess.