Gluten Antibodies and Autism

A team of American researchers have found a potential link between gluten antibodies and children with autism. The researchers at Columbia University Medical Center (CUMC) found this potential link when they examined blood samples and the medical records of 140 children, 37 of which were diagnosed with autism.

To increase accuracy of the study, only the 37 patients identified as having autism were selected. Led by Armin Alaedini, PhD, assistant professor of medical sciences in the Department of Medicine and the Institute of Human Nutrition, the blood samples were tested for antibodies to tissue transglutaminase, as well as antibodies to gliadin. The patients were also tested for genes associated with celiac disease, an autoimmune disorder that has been known to be triggered by gluten.

Gluten is a collection of more than 70 proteins found in wheat and similar grains. Those with a specific allergic reaction to gluten have celiac disease, while other people are known to have a gluten intolerance, where they experience digestive upset or neurologic symptoms after eating certain grains. The researchers were able to discover that the antibodies to gluten proteins of wheat were higher in children with autism than those without autism. The results also suggested a connotation between the elevated levels of antibodies and the presence of gastrointestinal symptoms in the affected children. However, they did not discover any linkage between the elevated gluten antibodies and celiac disease, as the children did not have true celiac disease, as they tested negative for the antigen markers.

There has been accumulating evidence supporting the concept that the immune system plays a role in a subset of autism patients. In addition, it is common for autistic children to have gastrointestinal symptoms. Painful conditions such as constipation, bloating, and diarrhea can trigger problem behaviors as well as feeding difficulties.

In the past few years, diets that exclude gluten have become progressively popular in the autism community. The effectiveness of gluten-free diets has yet to be confirmed through the means of controlled and blinded studies. The findings of the study do not suggest that putting a child with autism on a gluten-free diet has any benefit. “Such a conclusion cannot be drawn from this particular study. By itself, the increased antibody response to gluten does not necessarily indicate sensitivity to gluten or any pathogenic [disease-causing] role for the antibodies,” stated Dr. Alaedini.

Researchers suggest that further research is required to understand the relevance of the described antibodies in autism. “The IgG antibody response to gluten does not necessarily indicate sensitivity to gluten or any disease-causing role for the antibodies in the context of autism,” said Dr. Alaedini. “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.” “By themselves, these antibodies do not mean disease,” adds Dr. Dan Coury, medical director of Autism Speaks Autism Treatment Network. “However, when high levels occur with other symptoms, we begin to get a clearer picture.”

A better understanding of the body’s immune response to gluten may provide important clues regarding autism or offer biomarkers to identify a subset of patients that could potentially respond well to certain treatments.