Imbalance in gut bacteria may play role in Crohn’s disease

Strains of E. coli (one shown) have been linked to Crohn's disease. The bacterium is part of a larger family, Enterobacteriaceae, which, when more abundant than other "good" bacteria in the gut, could be a sign of the onset of the inflammatory bowel disease, research suggests.

Dr. W.A. Clark/CDC

By Ashley Yeager

March 12, 2014 at 4:55 pm

Identifying the onset of Crohn’s disease may be best done by looking at bacteria in the cellular linings of intestinal tissue.

Researchers tested intestinal tissue samples from 447 newly affected and 221 nonaffected people and found that having more Enterobacteriaceae, Pasteurellacaea, Veillonellaceae and Fusobacteriaceae and fewer Erysipelotrichales, Bacteroidales and Clostridiales bacteria was associated with inflammation levels. Stool samples did not provide as clear of a diagnosis, and antibiotics given to children with Crohn’s symptoms worsened the ratio of bad to good bacteria.

The results, published March 12 in Cell Host and Microbe, could explain why previous studies haven’t been able to find consistent differences between Crohn’s sufferers and healthy people: Stool samples may not identify which bacteria provoke inflammation when they interact with the intestinal wall.

Editor’s Note: This post was updated on March 13, 2014, to clarify the role the bacteria play in Crohn’s disease.