The discovery of specific bacterial populations and a core gene signature associated with Crohn's disease could lead to new diagnostic testing and improved treatment for inflammatory bowel disease (IBD), according to a study led by researchers at Cincinnati Children’s.

"This study identifies a set of bacteria that are associated with symptoms, and a group of anti-inflammatory genes that are associated with intestinal damage in children with Crohn's disease," says Lee (Ted) Denson, MD, Medical Director of the Inflammatory Bowel Disease Center, senior investigator for the study, published online July 8 in the Journal of Clinical Investigation. Yael Haberman Ziv, PhD, was the study’s first author.

Denson’s team studied tissue samples from the ileum, the lowermost portion of the small intestine, in a large number of children with Crohn's disease. They found specific types of bacteria and a "core" gene expression signature, both of which appear to affect inflammatory changes in the gut. Certain genes in the core signature appeared to be specifically associated with intestinal damage from deep ulcers.

The presence of these bacterial and gene expression factors could improve accuracy in predicting the outcomes of treatment, compared to conventional clinical diagnosis. This information might help doctors target patients who can benefit from more intensive treatment for Crohn's disease—particularly as newer biological therapies become available. 

Approximately 1.4 million American adults and children suffer from Crohn's disease or ulcerative colitis. Symptoms include abdominal pain, persistent diarrhea, rectal bleeding, fever, fatigue and weight loss. The illnesses can cause severe complications, including colon cancer in patients with long-term disease.

The study was sponsored by the Crohn’s & Colitis Foundation of America.