Evaluation of neurofilament light chain as a biomarker in dogs with structural and idiopathic epilepsy

Abstract

Background: Neurofilament light chain (NfL) is a frequently used biomarker in humans for both diagnostic and therapeutic monitoring purposes in various neurologic diseases. Hypothesis/Objectives: It was hypothesized that dogs with diagnosed structural epilepsy (SE) would have a significantly higher serum NfL concentrations compared to dogs with idiopathic epilepsy (IE). The secondary hypothesis was that dogs would have a significantly higher serum NfL concentrations when measured within 7 days after a seizure compared to being seizure-free for at least 30 days. Animals: Fifty client-owned dogs presented to the neurology service for evaluation of seizures were enrolled. Fourteen dogs had SE and 36 dogs had IE. Methods: Prospective cohort study performed on 52 serum samples obtained for NfL concentration measurement using single molecule array technology. Results: The median serum concentration of NfL in dogs with SE was significantly higher (109 pg/mL; range, 11.4-741.3 pg/mL) than in dogs with IE (17.7 pg/mL; range, 5.8-188 pg/mL; Wilcoxon rank sum test, P =.001). No significant relationship was found between serum NfL concentration and time of sampling in relation to the most recent seizure in dogs with IE. Conclusions and Clinical Importance: Serum NfL may serve as an adjunctive biomarker for the differentiation of SE and IE.