Inflammatory Bowel Disease

Learn more about inflammatory bowel disease

Inflammatory Bowel Disease: An Overview

More than one in 200 Americans live with inflammatory bowel disease (IBD). Scientists at BRI are studying IBD from a variety of angles to understand what goes wrong in the gut to trigger this disease and develop new ways to treat, stop and even prevent it.

Scientists in BRI’s innovative Gut Immunity Program are working to better understand immune system cells and processes within the gut. They’re using innovative tools like organoids (tiny replicas of the human gut) to accelerate their progress. Translational scientists at BRI are using knowledge of immune response processes to create therapies that target what has gone awry. We also work closely with the Center for Digestive Health at Virginia Mason Franciscan Health on clinical trials that study the effectiveness and safety of new treatments.

What Is Inflammatory Bowel Disease?

Inflammatory bowel disease (IBD) is the umbrella term for autoimmune disorders that cause ongoing (chronic) inflammation, pain and bleeding in the digestive tract (the series of hollow organs connected to one another that span from the mouth to the anus). Crohn’s disease and ulcerative colitis (UC) are the two most common forms of IBD. Both happen when the immune system mistakenly attacks the gut. The main difference between Crohn’s disease and ulcerative colitis is the location of this swelling and irritation (inflammation).

At least 1.6 million Americans live with inflammatory bowel disease, and the incidence is on the rise. IBD is usually diagnosed between ages 15-35 and 55-70. It affects men and women at about the same rate.

What is Crohn's disease?

Crohn’s disease can affect any of the organs along the digestive tract, though it is most common in the lining of the last part of the small intestine (the ileum) and the beginning of the large intestine.

Crohn’s disease typically causes inflammation in some places, but not others. The symptoms of Crohn’s disease usually develop over time, but sometimes they come on suddenly.

What is Ulcerative Colitis?

Ulcerative colitis (UC) causes inflammation and sores (ulcers) in the large intestine (which includes the colon and the rectum). It affects the innermost layer of the large intestine’s lining (the mucosa). Unlike Crohn’s disease, the inflammation in UC is continuous and not patchy. In most people, symptoms of UC develop over time rather than all at once.

What Causes Inflammatory Bowel Disease?

Inflammatory bowel disease (IBD) happens when the immune system mistakenly begins attacking the digestive tract, but scientists still don’t know exactly why it happens or how it starts. BRI scientists are working to pinpoint its causes and are currently investigating the interplay of genetics, environmental triggers, and why the immune system starts attacking healthy tissue.

What Are Risk Factors for Inflammatory Bowel Disease?

  • A close family member like a parent, sibling or child who has inflammatory bowel disease (IBD)
  • Age (usually diagnosed before age 30)
  • Northern European ancestry (though IBD can occur in any race)
  • Environmental factors like living in a northern climate, a developed country or an urban area
  • Imbalance in gut microbiome

What is the Difference Between Inflammatory Bowel Disease and Irritable Bowel Syndrome?

Though inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) have some common symptoms – like abdominal pain, constipation and diarrhea – they are not the same condition and require different treatments.

IBS is a group of symptoms that happen when the bowel isn’t working properly. In IBS, there is no inflammation of the tissue and no sign of tissue abnormality.

IBD is an autoimmune disease that causes inflammation in the digestive tract. IBD damages the tissue and causes tissue abnormalities.

IBS is estimated to affect as many as 15% of the United States’ population, making it much more common than IBD, which affects about 1.3% of people in the U.S. In addition, IBS is more common in women than in men, while IBD affects women and men at about the same rate.

What Is the Latest Research Into Inflammatory Bowel Disease?

For three decades, BRI has been working to understand the cells and processes that cause inflammatory bowel disease (IBD). Our research includes:

  • Identifying which cells and processes cause IBD.
  • Learning why immune cells attack harmless bacteria.
  • Understanding the role gut bacteria play in IBD and the immune system overall.
  • Finding ways to slow down or tire out the cells that cause IBD.
  • Figuring out how to match people to the treatments that will work best for them.

Clinical Research Studies in Digestive Health

We have ongoing clinical research studies in several areas of digestive health. Studies labeled as “Enrolling” are actively recruiting new participants while studies labeled as “Closed to Enrollment” are still active but no longer seeking new participants. 


Please email Digestive Health Research or call (206) 341-1021 for more information.



Are You Living With Inflammatory Bowel Disease?

Support inflammatory bowel disease research at BRI by participating in our gastrointestinal diseases biorepository.

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