Sialic acid and anti-ganglioside M1 antibodies are invaluable biomarkers correlated with the severity of autism spectrum disorder.

Background: Autism spectrum disorders (ASD) are devastating neurodevelopmental disorders that showed global increased prevalence. They are characterized by impairment of social communication and stereotyped patterns.
Objective: This study aimed at measuring the levels of total sialic acid (SA) and anti-ganglioside M1 (anti- GM1) IgG antibodies as essential biomarkers in a cohort of children with ASD to identify their diagnostic yield as well as their correlation with the severity of autistic behaviors.
Methods: The demographic characteristics, anthropometric measurements, and clinical data were recorded. The levels of total plasma SA and serum anti-GM1 IgG antibodies levels were measured in 100 children with ASD and 100 healthy controls. The severity of ASD-related symptoms was assessed by using the Childhood Autism Rating Scale (CARS).
Results: Children with ASD had significantly higher levels of both SA and anti-GM1 antibodies than healthy controls (p < 0.001). SA showed a statistically significant moderate diagnostic performance while anti-GM1 antibody showed a statistically significant high diagnostic in differentiating severe from mild to moderate autism. Moreover, both SA and anti-GM1 antibodies levels were significantly correlated to the severity of ASD symptoms (p < 0.001).
Conclusion: The significantly increased levels of SA and anti-GM1 antibodies in children with ASD and their correlation with autism-related symptoms suggest their possible etiopathogenic role in autism as one of the pediatric autoimmune neuropsychiatric disorders. However, further large-scale studies are still needed to explore their possible bidirectional relationship as biomarkers for autism.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2022 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.)