Gut bacteria linked to rheumatoid arthritis

Joanna Scott-Lutyens BA (Hons) DipION

A recent study carried out by the New York Langone Medical Center, published in the US online journal eLife, has demonstrated a link between the intestinal bacteria Prevotella copri and Rheumatoid Arthritis.

Professor Dan Littman of NYU School of Medicine states, “Studies in rodent models have clearly shown that the intestinal microbiota contribute significantly to the causation of systematic autoimmune diseases”.


Rheumatoid Arthritis

The study involved using complex DNA analysis to create a comparison between gut bacteria (visit the Probiotics Learning Lab for more) from faecal samples of patients with R.A and those of healthy individuals. Littman and his team discovered that Prevotella copri was found in higher numbers in 75% of patients recently diagnosed compared to 21.4% of healthy individuals, 11.5% in those with more long-term rheumatoid conditions and 37.5% of those with an alternative form of arthritis.

Interestingly, there appeared to be a link between the presence of higher numbers of P. copri alongside fewer numbers of beneficial bacteria of the Bacteroides (glossary definition, in the Probiotics Learning Lab: Bacteroides) genera.

It is thought that Prevotella copri contributes to colonic inflammation and offers an explanation into the systemic autoimmune response seen in Rheumatoid Arthritis. The exact mechanism is not known at this stage, and it is also unclear why the growth of P. copri appears to increase significantly in newly diagnosed patients. It was also noted that the P. copri extracted from the stool samples of those with newly diagnosed Rheumatoid Arthritis differed genetically from the P. copri extracted from healthy individuals.

There are now plans in place to explore results across different regions, taking into consideration geographical differences in gut flora. There will also be investigations into whether gut flora can be used as a biological marker guide treatment of Rheumatoid Arthritis.

Find out more about probiotic bacteria.


  1. Scher, J. U., Sczesnak, A., Longman, R. S., Segata, N., Ubeda, C., Bielski, C., Rostron, T., Cerundolo, V., Pamer, E. G., Abramson, S. B., Huttenhower, C., & Littman, D. R. (2013). Expansion of intestinal Prevotella copri correlates with enhanced susceptibility to arthritis. eLife, 2, e01202.
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