(N35) Neurofilament Light Chain as a Biomarker of Spinal Cord Diseases in Dogs

Abstract:

Background: Neurofilament light chain (NfL) is a neuron-specific cytoskeletal protein. Because damaged axons release NfLs into blood, NfL has been used as a biomarker for diagnosis of central nervous system diseases. General practitioners may have difficulties in distinguishing ataxia from lameness at times. Additionally, diagnosis of spinal cord diseases could be limited due to costs and concurrent disorders. Therefore, serum biomarker that can be easily measured is required.

Objectives: To evaluate the potential role of NfL as a biomarker for spinal cord disorders in dogs.

Animals: Thirty-seven healthy dogs, 9 normal Beagle dogs, 43 dogs with intervertebral disc herniation (IVDH), 13 dogs with syringomyelia (SM), 5 dogs with fibrocartilaginous embolism, and 3 dogs with acute non-compressive nucleus pulposus extrusion.

Methods: Cohort study. The level of serum NfL were measured using single-molecule array technology.

Results: There was a significant difference in the serum NfL level between the healthy dogs (12.6 pg/mL) and dogs with spinal cord disorders (91.1 pg/mL; P < 0.0001). The NfL level in dogs with SM (50.7 pg/mL) was significantly lower than those in dogs with IVDH (99.9 pg/mL; P = 0.005) and other diseases (241 pg/mL; P = 0.0018). The cut-off values to differentiate from healthy dogs were 42.0 pg/mL (spinal cord disorders, sensitivity 79.7%, specificity 97.8%), 42.6 pg/mL (IVDH, sensitivity 83.7%, specificity 97.8%), and 27.5 pg/mL (SM, sensitivity 69.2%, specificity 87%).

Conclusions and clinical importance: Neurofilament light chain could be a potential biomarker for identifying spinal cord disorders and differentiating SM from other spinal cord disorders.