No link found between autism and Lyme disease

U.S. researchers say they found no link between autism spectrum disorders and biomarkers for Lyme disease. Mary Ajamian of Columbia University Medical Center in New York and colleagues said a proposed link between Lyme disease and autism has garnered considerable attention. "Among individuals with autism spectrum disorders, rates of seropositivity -- blood serum test -- for Lyme disease of greater than 20 percent have been reported," Ajamian said in a statement. "However, controlled studies to assess serological evidence of infection with Borrelia burgdorferi -- the causative agent of Lyme disease -- in patients with autism are lacking." The researchers performed Lyme disease serological testing on serum samples from children with and without autism. For the analysis, 70 children with autism, 58 male with an average age 7.2 were tested. In addition, 50 controls -- 32 male and an average age 9 -- were included. "None of the children with autism or unaffected controls had serological evidence of Lyme disease by two-tier testing," the study authors wrote. "The data do not address whether Lyme disease may cause autism-like behavioral deficits in some cases. However, the study's sample size is large enough to effectively rule out the suggested high rates of Lyme disease or associated seroprevalence -- positive tests -- among affected children." The findings were published as a Research Letter at the Journal of the American Medical Association.