Salivary IgA correlate with recurrent respiratory infections and hyperreactivity in children with autism
Natalia Edith Furland, María Teresa Sindelar
Autism spectrum disorders (ASD) are characterized by impairment in social interactions, communication deficits, and restricted interests and behaviors. Accumulating evidence suggests that dysregulation of the immune system may be involved in the pathophysiology of ASD. The aim of the study was to assess if the severity of clinical and behavioral parameters of autistic children was associated with low levels of secretory IgA (sIgA) in saliva. We hypothesized that a decreased immune response in children with autism would decrease the levels of sIgA, as is the predominant antibody isotype in saliva and a marker of mucosal immunity. Saliva samples were obtained from 3-10 year-old children with ASD and age-matched typically developing Caucasian children from Patagonia region, Argentina. Autistic children with reduced levels of salivary IgA had a higher incidence of upper respiratory diseases compared to the controls. The reduction in sIgA levels also correlated inversely with the severity of the behavioral disorders. The patients with the most severe impairment in autism-related behaviors had the lowest levels of sIgA in the cohort studied. These findings suggest that sIgA could be an early indicator and possibly a biomarker of the dysregulation of the immune system in some children with autism. The characterization of immunological parameters in ASD has important implications for detection of a subset of individuals with ASD, and should be considered when designing therapeutic strategies to treat core symptoms and behavioral impairments of ASD.
Keywords
Autism, sIgA, saliva, respiratory infections, sensory hyper reactivity, irritability.