This artilce also appeared in the 2018, Volume 32, No. 3 issue of ARI's Autism Research Review International newsletter. 
A new study reports that the positive behavioral and gastrointestinal (GI) changes seen in children with autism spectrum disorders (ASD) following fecal transplants appear to be lasting.
Fecal transplants are currently used as a treatment for C. difficile infection and inflammatory bowel disease. A research team headed by James Adams at Arizona State University has been investigating the potential of this approach for treating children with ASD, who have a high rate of diarrhea, constipation, and other bowel problems that may be connected to their behavioral issues.
In their initial study (see ARRI 31/1, 2017), led by Dae-Wook Kang, 18 participants with ASD and GI problems underwent Microbiota Transfer Therapy, or MTT. Participants first received two weeks of antibiotic treatment and a bowel cleanse to prepare the GI tract. Next, they received one high dose of microbiota administered either orally or rectally, followed by a lower oral daily maintenance dose for 7 to 8 weeks. The researchers used a standardized product containing more than 99% bacteria obtained from healthy individuals and tested to ensure safety. The children also took an acid pump inhibitor to reduce stomach acidity and increase the survival rate of the microbes.
In the new study, led by Rosa Krajmalnik Brown, the researchers followed up with all 18 participants two years after treatment stopped. “Notably,” they say, “gastrointestinal symptoms were significantly reduced compared with the beginning of the original trial, and autism-related symptoms improved significantly after the end of treatment.” In addition, they say, “DNA-sequencing analyses revealed that changes in gut microbiota at the end of treatment still remained at follow-up, including significant increases in bacterial diversity and relative abundances of Bifidobacteria, Prevotella, and Desulfovibrio.”
