Autism affects one in 90 children in the U.S. Some children's symptoms are relatively mild, while others can be severely disabling. Yet, this developmental brain disorder is difficult to diagnose, since, until now, no biological markers specifically associated with ASD have been described. Now a team of University of Washington (UW) and Battelle scientists have identified metabolites in urine that potentially predict young children at risk of developing this disorder.
Autism is a group of developmental brain disorders, collectively called autistic spectrum disorder or ASD. Although ASD is mainly defined by impaired social interactions, difficulty in communicating, and repetitive behavioral patterns, numerous other symptoms can be present, including anxiety, depression, learning disabilities, sleep disorders, and gastrointestinal problems.
Currently, diagnosing a child with ASD involves a thorough evaluation by a team of health professionals with a wide range of specialties. Early intervention can reduce or prevent the more severe symptoms and disabilities associated with ASD.
Professor James Woods in the Department of Environmental and Occupational Health Sciences at the UW School of Public Health and senior scientists Nicholas Heyer and Diana Echeverria at Battelle Centers for Public Health Research and Evaluation evaluated porphyrins in the urine of children to determine if the levels of these metabolites could predict ASD.
While porphyrins are found in everyone's urine, the research team found that certain kinds of these metabolic byproducts are much higher in urine of some children with autism compared with typically developing children (non-autistic) of the same age. Additionally, when children with autism were randomly compared with typically developing children or children with other developmental disorders, these porphyrin biomarkers correctly identified more than thirty percent of autistic children without incorrectly identifying a single non-autistic child. The ability to detect porphyrins in a simple urine test allows for a rapid, low-cost and widely used screening test for identifying young children at a high risk for developing ASD.
"The significance of this biomarker is not only that it may facilitate earlier detection of autism risk, but also that it might help identify those ASD children whose symptoms are specifically associated with altered porphyrin metabolism. When validated in a larger study, this biomarker could help to identify a specific subset of ASD kids and improve the search for more focused treatment options for these children," said Dr. Woods.
The findings were published in this month's edition of Autism Research, and coincide with Autism Awareness Month. The full article can be found http://onlinelibrary.wiley.com/doi/10.1002/aur.236/full.
Partial funding for this research was provided by the National Institute of Environmental Health Sciences. Additional funding was provided by the Autism Research Institute and the Wallace Research Foundation.