The role of serum neurofilament light chain in an adult cohort of patients with acquired demyelinating syndromes of the central nervous system (P2-4.006)

Objective: To investigate the role of serum Neurofilament light chain (sNfL) levels in adult patients with acquired demyelinating syndromes (ADS) of the central nervous system. Background: The concentration of sNfL has been found to increase in serum of patients with CNS diseases, associated with axonal injury or degeneration. Design/Methods: A total of 347 patients were evaluated, a propensity score matching was performed to select patients with homogeneous baseline characteristics. It retained n=17 multiple sclerosis(MS), n=15 Myelin Oligodendrocytes Glycoprotein Antibody associated Disorder(MOGAD), n=16 Neuromyelitis Optica Spectrum Disorders(NMOSD) patients and n=24 Healthy Controls(HCs). Demographic, clinical features and samples were collected at disease onset(T0). SNfL was measured using ultrasensitive single-molecule array assays (SIMOA). MOG-IgG and AQP4-IgG were analyzed by an in-house cell-based assay. In a subgroup of NMOSD and MOGAD patients, the autoantibodies and sNfL were longitudinally evaluated after the DMD initiation(T1). Results: MOGAD patients showed a significant lower sNFL levels compared to MS(median 16,47pg/mL range 5,10–71,78 vs 7,34 range 2,43–115,43; p=0.01) and NMOSD adult patients(median 16,46pg/mL range 4,2–196,47; p=0.02). All groups had an increased sNFL value compared to HCs(median 5,64pg/mL range 2,47–8,84; p<0.0001). A positive significant correlation was found between sNfL and EDSS scores in MOGAD (r=0.636; p=0.005), NMO-AQP4 (r=0.908; p<0.0001) and MS patients (r=0.534; p = 0.014). No correlation was found between MOG-IgG titers and sNfL levels (p=0.294). In NMOSD (p=0,04) and MOGAD (p=0,008) patients presented a decrease of the antibody titer at T1. In 2/6 NMOSD and 4/10 MOGAD patients, sNfL resulted increased at T1. Conclusions: To our knowledge, this is the first study where sNfL levels were compared in a matched cohort of ADS patients and at the same disease stage. Our results confirm the value of sNfL as a clinically meaningful blood biomarker of disease severity and activity in all groups and that the antibody titer is not related to the axonal damage.