
Signs of the debilitating intestinal disease of Crohn’s disease can be detected in routine blood tests up to eight years before symptoms appear and up to three years before the diagnosis of ulcerative colitis. The discovery suggests that the early stages of inflammatory bowel diseases may begin much earlier than previously assumed and may eventually allow doctors to intervene before serious damage is done.
Crohn’s disease and ulcerative colitis are inflammatory bowel diseases (IBD) that affect more than 500,000 people in the UK alone. They are caused by the immune system mistakenly attacking the intestine, causing painful sores, inflammation and symptoms such as abdominal pain and diarrhea.
“These conditions often affect young people at a time when they are trying to finish their education, have relationships and keep their jobs, and can be devastating,” said Dr. James Lee, a gastroenterologist at the Crick Institute in London, who led the study. . investigation. “Part of the reason we did this study is because there is a proportion of people who already have fairly established intestinal damage at the time of diagnosis.”
Some of them may immediately require life-changing surgery, such as a stoma, a surgically created hole that allows bodily waste to be removed from the body through a colostomy bag.
Because this type of damage takes time to accumulate, researchers have long suspected that there must be a preclinical phase of the disease, in which damage occurs but people do not experience symptoms, raising the possibility that such changes may be detectable in the blood.
To investigate, Lee and his colleagues turned to a database of Danish electronic medical records. They examined standard blood tests performed on 20,000 people with IBD in the 10 years before their diagnosis, comparing them with another 4.6 million people without IBD.
Their results, published in Cell Reports Medicine, identified subtle changes in several minerals, blood cells and proteins associated with inflammation up to eight years before diagnosis of Crohn’s disease and three years for ulcerative colitis.
“This tells us that the origins of these diseases are happening much earlier than we thought, which could give us a huge window of opportunity to intervene with lifestyle modifications or get people on effective treatment much, much sooner.” . We hope we can save people from having to directly undergo a major operation at the time of diagnosis,” Lee said.
Most of these changes would not have been individually flagged as cause for concern because they were within normal ranges: the pattern was only detected by using an algorithm to trawl through a huge data set of patient records.
The next step is to further refine the algorithm to see if this improves its ability to identify who is at risk of developing IBD in the future and to investigate whether treatment or prevention can reduce this risk.
“Anything that can speed up the process of getting an accurate diagnosis is a hugely positive step in the right direction,” said Sarah Sleet, chief executive of Crohn’s & Colitis UK.