Is autism an autoimmune disease? Paul Ashwood, Judy Van de Water * Department of Internal Medicine, Division of Rheumatology, and UC Davis M.I.N.D. Institute, University of California, Davis, 95616, United States Accepted 17 July 2004 Available online 3 October 2004 Contents 1. Introduction..................................................... 558 2. The neuroimmune system in ASD ......................................... 558 3. Autoimmunity in ASD ............................................... 558 4. The role of xenobiotics in autism ......................................... 560 5. Summary ...................................................... 560 Acknowledgement .................................................... 561 Take-home messages .................................................. 561 References ........................................................ 561 1568-9972/$ - see front matter D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.autrev.2004.07.036 * Correspoding author. Tel.: +1 530 752 2154; fax: +1 530 752 4669. E-mail address: javandewater@ucdavis.edu (J. Van de Water). Abstract Autism spectrum disorder (ASD) is a spectrum of behavioral anomalies characterized by impaired social interaction and communication, often accompanied by repetitive and stereotyped behavior. The condition manifests within the first 3 years of life and persists into adulthood. There are numerous hypotheses regarding the etiology and pathology of ASD, including a suggested role for immune dysfunction. However, to date, the evidence for involvement of the immune system in autism has been inconclusive. While immune system abnormalities have been reported in children with autistic disorder, there is little consensus regarding the nature of these differences which include both enhanced autoimmunity and reduced immune function. In this review, we discuss current findings with respect to immune function and the spectrum of autoimmune phenomena described in children with ASD. D 2004 Elsevier B.V. All rights reserved. Keywords: Autism; Autoimmune; Neurodevelopment Autoimmunity Reviews 3 (2004) 557 – 562 www.elsevier.com/locate/autrev