Serum neurofilament light chain levels are increased in patients with a clinically isolated syndrome

Background Neurofilament light chain (NfL) represents a promising biomarker for axonal injury. We present the first exploratory study on serum NfL in patients with a clinically isolated syndrome (CIS) and healthy controls.
Methods We investigated serum NfL levels in 100 patients with CIS with a short conversion interval to clinically definite multiple sclerosis (MS); 98 patients with non-converting CIS; and 92 healthy controls.
Results NfL levels were higher in FC and NC than in healthy controls. When grouping FC and NC, increased serum NfL concentration was also associated with increasing numbers of T2 hyperintense MRI lesions, gadolinium-enhancing lesions and higher disability scores at CIS diagnosis.
Conclusions If replicated in future studies, serum NfL may represent a reliable and easily accessible biomarker of early axonal damage in CIS and MS.