The study, published in the journal PLoS One, found an association between the elevated antibodies and the presence of gastrointestinal symptoms in the affected children, but there was no connection between the elevated antibodies and celiac disease -- an autoimmune disorder known to be triggered by gluten.
Armin Alaedini, an assistant professor of medical sciences at Columbia University Medical Center, and colleagues looked at blood samples and medical records of 140 children.
Thirty-seven of the children were diagnosed with autism and the rest were unaffected siblings or healthy control subjects. To increase diagnostic accuracy, only patients identified as having autism according to two well-recognized diagnostic instruments, Alaedini said.
The blood samples were tested for antibodies and also tested for genes encoding certain human leukocyte antigens, which are strongly associated with celiac disease, Alaedini said.
"The antibody response to gluten does not necessarily indicate sensitivity to gluten or any disease-causing role for the antibodies in the context of autism," Alaedini said in a statement. "But the higher levels of antibody to gluten and their association with gastrointestinal symptoms point to immunologic and/or intestinal permeability abnormalities in the affected children."
Alaedini noted a better understanding of the immune response to gluten might yield novel clues about autism or offer biomarkers to identify a subset of patients that would respond to certain treatment strategies.