A large international study of patients with MS showed differences in gut bacteria among those with MS compared with healthy patients from the same households, according to findings published in Cell. Sergio Branzini, PhD, and colleagues recruited 576 patients with MS (36% untreated) from the US, the UK, Spain, and Argentina, and enrolled
an equal number of genetically unrelated people from the same households to serve as the control group, for a total of 1,152 participants. The phytate degradation pathway was over-represented in untreated MS, while pyruvate-producing carbohydrate metabolism pathways were significantly reduced. Microbiome composition, function, and derived metabolites differed in response to disease-modifying therapies; patients treated with interferon beta-1a had reduced concentrations of short-chain fatty acids in feces but higher concentrations in blood. The researchers also observed distinct microbial networks in patients with untreated MS and healthy controls. Collectively, the findings indicate specific gut microbiome associations with MS risk, course, and progression, according to the study results. “This is the reference study that will be used by the field for years to come,” Dr. Branzini said in a statement.