Pro-inflammatory cytokines in autistic children in central Saudi Arabia

OBJECTIVE: Abnormal inflammatory immune response might contribute to autism. Pro-inflammatory cytokines could induce some of the symptoms and signs of autism. Such as, social withdrawal eating and sleep disturbance. The aim of the current study was to examine whether autism spectrum disorders in Riyadh area are accompanied by activation of the pro-inflammatory response system.

METHODS: The study was conducted in the Riyadh area between September 2003 and April 2004. Seventy-seven autistic child from the Riyadh area participated in the study, with confirmed diagnosis according to E-2 diagnostic criteria for autistic spectrum disorders. The parents/guardians filled a simple related questionnaire, then serum concentrations of tumor necrosis factor-a (TNF-a), interleukin-1 (IL-1) and interleukin-6 (IL-6) were measured in 65 autistic, 8 attention deficit disorder, 2 children with Rett’s syndrome and 2 children with Asperger syndrome. The results were compared to age, and sex matched control children.

RESULTS: This study showed a significantly increased production of TNF-a, IL-1 and IL-6 from the sera of autistic, attention deficit disorder, Rett’s syndrome and Asperger syndrome children. There was no correlation between TNF-a, IL-1 or IL-6 and the degree of autism or the age of the affected child. Significant higher incidence of social withdrawal, sleeping and eating disorders were found among autism spectrum disorders compared to control.

CONCLUSION: These results suggest that autism may be accompanied by an activation of the macrophages. It is hypothesized that increased production of pro-inflammatory cytokines could play a role in the pathophysiology of autism spectrum disorders, such as social withdrawal, eating and sleeping disorders.