Study: Invasive Bacteria Links Arthritis and Crohn Disease

A new study identified a bacterial connection between Crohn disease and peripheral spondyloarthritis (SpA) in the form of Escherichia coli (E coli).

Previous research has suggested connections between Crohn disease and SpA, but the mechanisms behind the gut microbiome’s influence on this condition are less well understood.



To further investigate, researchers examined the fecal microbiomes of participants with Crohn disease with or without SpA using flow cytometry. The researchers also examined a mouse model of SpA.

Overall, patients with CD-SpA had a higher prevalence of immunoglobulin A-coated E coli than patients with only Crohn disease.


Related Content: Integrating Care in Spondyloarthritis: Applying Diagnostic Tools and Current Evidence Across Disciplines


“In comparison to non-[adherent-invasive] E coli, colonization of germ-free mice with CD-SpA E coli isolates induced T helper 17 cell (TH17) mucosal immunity, which required the virulence-associated metabolic enzyme propanediol dehydratase (pduC),” the researchers wrote.

When researchers modeled the increases in mucosal and systemic TH17 found in CD-SpA patients in mice, they found that the colonization of adherent-invasive E Coli (AIEC) lead to more severe colitis or inflammatory arthritis.

Their results may assist in the development of diagnostic tools and methods for identifying patients with Crohn disease at risk for SpA. In addition, the mechanisms that show how AIEC increased TH17-dependent inflammation may help with the creation of medical or biological therapies to treat CD-SpA.

“If we can block the ability of bacteria to induce inflammation, we may be able to kick Crohn’s disease and spondyloarthritis into remission,” said coauthor Dr Kenneth Simpson, professor of small animal medicine at Cornell’s College of Veterinary Medicine and whose laboratory characterized the E coli identified in the study.