Prevalence of autism spectrum disorders in relatives of patients with selective immunoglobulin A deficiency.

Background: An association of selective IgA (immunoglobulin A) deficiency in individuals with autism has been previously described. The objective of this study was to examine the incidence of autism spectrum disorders (ASD) in children and siblings of selective IgA deficient patients.

Objective: to assess the likelihood of parents with the most common type of primary immunodeficiency (selective IgA deficiency) having children with ASD and to investigate the occurrence of ASD in siblings of the immunodeficient patients.