Children with autism harbor significantly fewer types of gut bacteria than those who are not affected by the disorder, researchers have found.
This reduction in commensal bacteria diversity could make children with autism more vulnerable to pathogenic bacteria, members of the Autism Microbiome Consortium report in PLOS One today.
Arizona State University’s Rosa Krajmalnik-Brown, Ph.D., and her colleagues also found that autistic children also had significantly lower amounts of three critical bacteria—Prevotella, Coprococcus, and Veillonellaceae—involved in carbohydrate degradation and fermentation.
"One of the reasons we started addressing this topic is the fact that autistic children have a lot of GI problems that can last into adulthood," Dr. Krajmalnik-Brown said in a statement. "Studies have shown that when we manage these problems, their behavior improves dramatically."
She and her colleagues studied a cohort of 20 healthy and 20 autistic children between three and 16 years old, using pyrosequencing to analyze their gut flora from fecal samples. The researchers found that reduced diversity of gut microbes correlated with the presence of autistic symptoms.
In particular, they found that Prevotella species were most dramatically reduced among samples from autistic children—especially P. copri. Dr. Krajmalnik-Brown and her colleagues note that these bacteria are thought to play a key role in the gut microbiome. “We think of Prevotella as a healthy, good thing to have," she said.
The researchers also suggest that their study lays the groundwork for future research toward the development of diagnostic tools to pinpoint autism based on gut flora, or the generation of targeted treatments for autism spectrum disorder-associated gastrointestinal problems.
The study appeared online in PLOS One July 3.