Warning signs could predict inflammatory bowel disease a decade before diagnosis | Medical research

Antibody profiles in people’s blood could predict the onset of inflammatory bowel disease (IBD) a decade before diagnosis, according to research that offers hope for early detection of the disease.

Crohn’s disease and ulcerative colitis, the two main forms of IBD, are usually only treated after symptoms appear, when the intestine has already been damaged. But scientists have discovered that the immune system sends warning signals up to ten years before diagnosis, paving the way for potentially earlier detection and even prevention.

“For too long, we have only been able to treat inflammatory bowel disease after the damage has been done, and for many people that is too late,” said Dr. Arno Bourgonje of Groningen University Medical Center in the Netherlands and the Icahn School of Medicine at Mount Sinai in New York.

“What we have shown is that the disease begins years before symptoms appear and that the immune system leaves warning signs long before diagnosis,” Bourgonje added. “It’s not yet a test that can tell someone they’re going to get sick, but it’s an important step toward detecting illness earlier and one day preventing it.”

At least 3.8 million people worldwide live with IBD, an immune disease that causes chronic inflammation of the digestive tract, causing pain, diarrhea and fatigue. The exact cause is unknown, but a poor immune system, genetics, and microbes living in the gut can all contribute.

Treatment relies on anti-inflammatory and immunosuppressive medications, but many patients do not respond to them and a significant number undergo surgery to remove damaged sections of the intestine. Long-term inflammation also increases the risk of bowel cancer. This has prompted scientists to look for early signs of the disease, hoping to identify people at risk before the damage begins.

Bourgonje and his colleagues at Mount Sinai and the Medical University of Vienna performed tests on blood samples taken from U.S. military personnel. They looked at 2,000 samples from 500 people, 200 of whom later developed Crohn’s disease and 200 of whom developed ulcerative colitis. The other 100 did not develop any of these conditions.

The blood samples were analyzed for antibodies that the immune system might have produced in response to hundreds of thousands of protein fragments from bacteria, viruses, food and even the body’s own tissues.

In people who developed Crohn’s disease, antibodies against the Epstein-Barr virus, which causes glandular fever, were more common and the differences were already visible a decade before diagnosis. The signal was stronger in those who later developed a more serious and complicated disease, which could narrow the intestine or create abnormal ducts.

People who developed ulcerative colitis had a different profile, including antibodies to one of the body’s proteins.

The findings, published in the journal Gut and presented at the United European Gastroenterology meeting in Barcelona, ​​need to be confirmed in other groups of people, and the results show a link rather than proving that infections cause IBD. But the hope is that IBD could eventually go the way of type 1 diabetes, where a blood test can identify people whose immune systems have begun attacking the pancreas before symptoms appear, allowing treatment that delays the onset of the disease.

James Lindsay, a professor of gastroenterology at Barts Health, who was not involved in the research, said the study provided “important information about the causes of Crohn’s disease and ulcerative colitis, potentially adding new tools to help identify people at risk for IBD.” But he cautioned that these techniques were “largely a research tool” and were not yet ready for clinical use.

Marianne Radcliffe, chief executive of Crohn’s & Colitis UK, a national patient charity, said: “For people affected by Crohn’s and colitis, research like this is an important step forward. Each new piece of information helps to better understand how these conditions develop, including changes that can occur years before symptoms appear.”