NEFL and autoimmune encephalitis: One study examined CSF levels of NfL in a cohort of 25 subjects with autoimmune encephalitis (including seronegative antibody syndromes, NSAS [n =5; 4 NMDAR and 1 LGI1], and intracellular antibody syndromes) with evidence of elevated CSF NfL at the time of diagnosis correlating to disability at 1 year (18).