Antibiotics: Is There a Connection Between Gut Bacteria and Autism?

An article published in Microbial Ecology in Health and Disease explores a possible correlation between gut flora and autism after a father reported improvements in his son’s symptoms after taking a round of antibiotics for strep throat. John Rodakis, a Harvard MBA venture capitalist with a background in molecular biology, said,

“[He] began making eye contact, which he had previously avoided; his speech, which was severely delayed, began to improve markedly; he became less ‘rigid’ in his insistence for sameness and routine; and he also displayed an uncharacteristic level of energy, which he had historically lacked.”

These changes inspired Rodakis to do some research, uncovering a 1999 study from Chicago Rush Children’s Hospital sharing similar results. A more recent study from Arizona State University found that children with autism have less diversity in the types of bacteria found in the gut than children without the diagnosis. These studies, along with his personal observations, led him to meet with Dr. Richard Frye, head of the Autism Research Program at Arkansas Children’s Hospital Research Institute. Together, they collaborated with other researchers to explore the possibility of an autism-gut flora link. They presented their findings at the First International Symposium on the Microbiome in Health and Disease with a Special Focus on Autism in June, leading to the publication of a special edition of Microbial Ecology in Health and Disease focusing on autism and the microbiome.

The microbiome refers to the trillions of bacteria that live in the human digestive system. Most provide benefits such as delivering nutrients to the body, developing the immune system, and regulating metabolism. Others are less beneficial, and can cause problems when the “bad” bacteria grows rampant and crowds out space for the “good” bacteria. Antibiotics kill both kinds of bacteria, though it is currently not clear exactly how a round of antibiotics can affect the symptoms of autism.

Rodakis hopes this research can shed some light on this. He says,

“I was determined to better understand this phenomenon because I believed that if we could understand the biological basis of his improvements , we might gain insight into how autism works and be able to help him. . . Current research is demonstrating that gut bacteria play previously undiscovered roles in health and disease throughout medicine. The evidence is very strong that they also play a role in autism. It’s my hope that by studying these antibiotic-responding children, we can learn more about the core biology of autism.”

He cautions parents not to rush out and start feeding their children antibiotics.

The link between the gut microbiome and autism is still being researched, and long-term antibiotic use can result in significant side effects. He also points to studies showing that certain individuals with autism displayed an increase in symptoms while taking antibiotics, and it is still unclear why this is the case. Rodakis and Dr. Frye are hopeful that future research will lead to answers, and possible treatments for some of the more debilitating symptoms of autism.