A recent study, however, did not find higher rates of Lyme disease among autistic children when compared to typically developing children.
It's not known whether Lyme disease can cause autistic behaviors. However, autistic children did not appear to be at higher risk for Lyme disease based on this study's findings.
"Protect yourself from ticks when outdoor."
The study, led by Mary Ajamian, MS, of the Department of Medicine at Columbia University Medical Center in New York City, aimed to find out whether Lyme disease was more common among children with autism than among other children.
The researchers collected blood from 120 children, aged 2 to 18. The participants included 70 children with autism, 35 siblings of those children who did not have autism and 15 unrelated children without autism.
The participants were primarily from Connecticut, New Jersey, New York, other parts of the northeastern US or parts of the western US.
The researchers were looking in the children's blood for antibodies of an infection from Borrelia burgdorferi, the bacteria that causes Lyme disease. They used two tests to analyze the blood.
One of the patients with autism tested positive for having antibodies against B. burgdorferi, and four of the autistic children had borderline levels that indicated possible infection.
Among the children without autism, four tested positive for antibodies against the bacteria and one had borderline levels.
When these samples were analyzed with the second test type, all were found to be negative for antibodies against the bacteria.
"None of the children with autism or unaffected controls had serological evidence of Lyme disease," the researchers wrote. They acknowledged that they did not have information about the children's lifestyles, including how much time they spent outside.
Also, their study's findings "do not address whether Lyme disease may cause autism-like behavioral deficits in some cases," they wrote.
However, the number of participants in the study was high enough that they could determine that Lyme disease does occur in a proportionally higher number of children with autism.
The study was published April 30 as a research letter in JAMA. The research was funded by the Department of Defense, the National Institutes of Health, the Autism Genetic Resource Exchange as part of Autism Speaks, the National Institute of Mental Health and the Clinical and Translational Science Center of the Weill Cornell Medical College.
One author has received grants from Immunetics Inc., Bio-Rad, DiaSorin, Inc. and BioMerieux for research related to Lyme disease, and he has provided expert witness testimony in Lyme disease-related malpractice cases. He has also consulted for Baxter regarding development of a Lyme vaccine.
Another author has received a grant from The Hartwell Foundation for autism research, and another has received research funds for Lyme disease and autism research from the Lyme Research Alliance. No other disclosures were reported.