Cytokine concentrations in the cerebrospinal fluid of great danes with cervical spondylomyelopathy.

BACKGROUND

Chronic inflammation is involved in the pathogenesis of human cervical spondylotic myelopathy and could also play a role in cervical spondylomyelopathy (CSM) in dogs.

HYPOTHESIS/OBJECTIVES: That cerebrospinal fluid (CSF) cytokine concentrations would differ between clinically normal (control) and CSM-affected Great Danes (GDs), with affected GDs showing higher levels of inflammatory cytokines, such as interleukin (IL)-6 and monocyte chemoattractant protein-1/chemokine ligand 2 (MCP-1/CCL2).

ANIMALS

Client-owned GDs: 15 control, 15 CSM-affected.

METHODS

Prospective study. Dogs underwent cervical vertebral column magnetic resonance imaging and collection of CSF from the cerebellomedullary cistern. Cytokine concentrations were measured using a commercially available canine multiplex immunoassay. Cytokine concentrations were compared between groups. Associations with the administration of anti-inflammatory medications, disease duration and severity, severity of spinal cord (SC) compression, and SC signal changes were investigated in affected GDs.

RESULTS

Affected GDs had significantly lower MCP-1/CCL2 (mean 138.03 pg/mL, 95% confidence interval [CI] = 114.85-161.20) than control GDs (212.89 pg/mL, 95% CI = 165.68-260.11, P = .028). In affected GDs, MCP-1/CCL2 concentrations correlated inversely with the severity of SC compression. There were no associations with administration of anti-inflammatory medications, disease duration, or disease severity. IL-6 concentrations were significantly higher (2.20 pg/mL, 95% CI = 1.92-2.47, P < .001) in GDs with SC signal changes.

CONCLUSIONS AND CLINICAL IMPORTANCE

Lower MCP-1/CCL2 in CSM-affected GDs might compromise clearance of axonal and myelin debris, delay axon regeneration, and affect recovery. Higher IL-6 in CSM-affected GDs with SC signal changes suggests more severe inflammation in this group.