Lead author Brent Williams of the Columbia University Mailman School of Public Health and colleagues found more than half of the children diagnosed with autism and gastrointestinal disturbances had Sutterella in intestinal biopsy tissue.
Sutterella was absent in biopsies from typically developing children with gastrointestinal disturbances. Not only was Sutterella present in the intestines of children with autism, but relative to most genera of bacteria, it was present at remarkably high levels.
Sutterella species have been isolated from human infections previous to this study, but it remains unclear whether this bacterium is a human pathogen.
The researchers examined intestinal biopsies from 32 patients -- 23 diagnosed with autism and nine typically developing children. Previous studies investigating a link between the microbiota and autism have utilized stool samples, but this study was unique in investigating bacteria adherent to the intestinal wall, which may be different than what is shed in the stool.
"These findings shine a light on a bacterium about which we know very little, in a disorder for which we have few answers," Williams said. "There is much work to be done toward understanding the role Sutterella plays in autism, the microbiota, infections and inflammation."