New research, published this week in Journal of the Neurological Sciences, shows that a reduced abundance of a particular bacterial phylum in the gut is associated with subsequent relapse risk in pediatric multiple sclerosis (MS). The pilot study, led by Dr. Helen Tremlett and Dr. Emmanuelle Waubant (University of California, San Francisco), may offer a potential drug target to decrease relapse risk in some patients.

Researchers analyzed stool samples from 17 children who had recently been diagnosed with MS, and evaluated their subsequent relapse risk over a period of 20 months to determine whether microbes – or an imbalance of them – played a role in MS relapse risk.

They found that a depletion in Fusobacteria was associated with more than three times the risk of an earlier relapse during the 20-month period.

Fusobacteria are a group (phylum) of bacteria that are involved in digestion, but that are also associated with diseases including cancers of the digestive tract, Crohn’s disease, and obesity. That a depletion in the bacteria is associated with increased risk of relapse in a neurological condition such as MS means that further investigation into this particular phylum of bacteria and their role in modifying MS risk is warranted.

“We are cautiously optimistic with these preliminary findings,” says Dr. Tremlett. “Firstly, we need to validate (and replicate) findings in a larger group of children with MS. We also need more data to understand which bacterial species or strains within this broad phylum of Fusobacteria might be of greatest relevance.”

The MS Society of Canada and the MS Scientific Research Foundation have provided funding to pursue a larger gut microbiome study in pediatric MS, which is part of a collaboration with the Canadian Pediatric Demyelinating Disease study led by Dr. Brenda Banwell.

The US Network of Pediatric Multiple Sclerosis Centres is also a study partner in this new study, led by Dr. Emmanuelle Waubant at the University of California, San Francisco.

The current study was in collaboration with colleagues at the University of California, San Francisco, led by Dr. Emmanuelle Waubant. The study was funded in part by the National MS Society (USA, PI Waubant), National Institutes of Health (USA, PI Waubant) and The Race to Erase MS (PI Waubant) and the Canada Research Chair program (PI Tremlett).