Increased cerebrospinal fluid neurofilament light chain in central nervous system inflammatory demyelinating disease.

Background: Central nervous system (CNS) inflammatory demyelinating disease (IDD) is an immune-mediated disease that is pathologically characterized by demyelination and inflammatory infiltration in the CNS and includes clinically isolated syndrome (CIS), multiple sclerosis (MS), and neuromyelitis optica spectrum disorders (NMOSD). IDD is usually characterized by variable symptoms, multivariate imaging, uncertain reactions to treatment, and a variable prognosis, which makes it difficult to diagnose early. In recent years, the role of the neurofilament light chain (NFL), an axonal injury biomarker, in IDD has become increasingly important. We will detect and analyse cerebrospinal fluid (CSF) NFL levels in IDD and normal control patients to determine the significance of NFL in the diagnosis and prognostic prediction of IDD.

Methods: A total of 41 CIS, 34 MS and 73 NMOSD patients and 40 other patients with conditions such as neurosis and migraine with lumbar puncture were enrolled as the patient groups and the normal control (NC) group from the population of in- and outpatients of the Department of Neurology of the Sixth Medical Centre of Chinese People's Liberation Army General Hospital from January 2014 to October 2016. Clinical and neuroimaging features of the patient groups as well as CSF samples from both types of groups were collected, and the NFL levels of CSF were measured by enzyme linked immunosorbent assay.

Results: CSF NFL levels in the CIS, MS and NMOSD groups were significantly higher than those in the NC group (P < 0.05, analysis of variance of NFL levels was performed after logarithmic transformation based on 10). There were no statistically significant differences in the CSF NFL levels among the CIS, MS and NMOSD groups (P > 0.05). The NFL levels of CSF in the CIS, MS and NMOSD groups were correlated with the expanded disability status scale score and enhancement in gadolinium-magnetic resonance imaging (all P < 0.05). Gender, oligoclonal band in CSF, aquaporin 4 antibody and 25‑hydroxy vitamin D [25(OH)D] in serum were not related to the NFL levels (P > 0.05).

Conclusion: The NFL level of CSF is conducive to assessing the severity and probable progress of IDD but is not helpful in distinguishing IDD among Chinese.