A new small study revealed that fecal transplants could help relieve both gastrointestinal and behavioral symptoms of children with autism disorder.

The study, published in the journal Microbiome, showed that changing the gut flora of children with autism could not only relieve stomach problems, but can also positively affect some of the behavioral symptoms associated with the disorder.

"Transplants are working for people with other gastrointestinal problems," explained Ann Gregory, microbiology graduate student at the Ohio State University and one of the lead authors of the study, in a press release. And, with autism, gastrointestinal symptoms are often severe, so we thought this could be potentially valuable. "And, with autism, gastrointestinal symptoms are often severe, so we thought this could be potentially valuable."

For the study, the researchers recruited 18 children, aged 7 to16, clinically diagnosed with autism disorder and gastrointestinal problems. The children were given a two-week course of antibiotics to clear out much of the flora in their guts. Then, the researchers gave the children liquids with large quantity of bacteria taken from fecal donors. The fecal transplant was performed ether rectally or orally.

For the following seven to eight weeks, the children received a lower dose of fecal transplant in the form of a powder mixed in smoothies.

By the end of the treatment, the researchers observed a 22 percent decrease in doctor-reported symptoms. After eight weeks, the doctor-reported behavioral symptom of autism was 24 percent lower compared with the ratings at the beginning of the trial. The researchers also recorded a 82 percent drop on the average score on a scale for ranking gastrointestinal symptoms by the end of the treatment.

Despite their positive results, the researchers noted that they are cautiously optimistic of their findings. Their study is relative small and heavily relied on parents' observation of their children, opening doors for the so-called placebo effect. The researchers plan to recreate their result in a larger clinical study to better understand the mechanism behind the effectiveness of the fecal transplant.