However, the serum NfL level is a proposed biomarker of pure LMN damage in diseases such as inherited peripheral neuropathy (23), vasculitic neuropathy (24), and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) (25), suggesting that body fluid NfL levels permit estimation of the amount of axonal degeneration. This evidence concerns the gene NEFL and chronic inflammatory demyelinating polyradiculoneuropathy.