Ten years before the diagnosis: what 2,000 blood samples showed
What happened
Researchers have found patterns in people's blood that showed up as much as 10 years before they were diagnosed with inflammatory bowel disease. The work was presented on 19 October 2026 at UEG Week in Barcelona. UEG stands for United European Gastroenterology. Its yearly meeting is one of the largest gut health conferences in the world. The findings were picked up more widely on 24 October 2026. The study was led by Dr Arno Bourgonje. His team looked at 2,000 blood serum samples taken from 500 people over many years. Of those 500 people, 200 later developed Crohn's disease. Another 200 later developed ulcerative colitis. The remaining 100 stayed healthy and acted as a comparison group. They were matched to the others by age and sex. The samples had been collected at four points: at the time of diagnosis, and at roughly two, four and ten years before it. The team then did something unusual. They tested each sample against about 357,000 different targets, called antigens. These came from bacteria, viruses, food and the body's own tissues. In total they measured 123,980 different antibodies. Antibodies are proteins the immune system makes to tag things it wants to deal with. Measuring this many at once gives a very wide picture of what someone's immune system has been reacting to. Three findings stood out. First, people who went on to develop either condition had noticeably less antibody variety than the healthy comparison group. That difference was already visible ten years before diagnosis. Second, the two conditions looked different from each other. In people who later developed Crohn's disease, antibody responses to herpesviruses and to a bacterial protein called flagellin were raised. This was strongest in those who later had more complicated Crohn's, or disease in the ileum, the last part of the small intestine. In people who later developed ulcerative colitis, responses to herpesviruses and to the body's own tissues went up instead. Third, in both groups, antibody responses to a family of bacteria known as encapsulated bacteria fell away as diagnosis came closer. The team then trained computer models on these patterns to see how well they could separate the groups.
Why this matters
Inflammatory bowel disease, usually shortened to IBD, is the umbrella name for Crohn's disease and ulcerative colitis. Both cause the gut to become inflamed. Both are lifelong. Both can flare up and settle down again. It is far more common than many people assume. Research from the University of Nottingham, funded by Crohn's & Colitis UK and Coeliac UK, looked at GP records covering 38.3 million people. It found that more than half a million people in the UK live with Crohn's or colitis. That is about 1 in every 123 of us, and closer to 1 in 67 among people over 70. The previous working estimate had been around 300,000. At the moment, the path to a diagnosis usually starts with symptoms. Someone has months of pain, diarrhoea, blood, tiredness or weight loss, and eventually tests confirm what is going on. By then the gut has often already taken damage. That is why the ten-year figure caught people's attention. If the immune system is already changing a decade before the first clear symptom, there may be a long window in which something useful could be done. There is a second, quieter point in the findings. The models were also able to tell apart people whose Crohn's later became complicated from those whose did not, roughly ten years ahead. Dr Bourgonje said that was the part his team found most striking, because it suggests the pattern is not simply the result of the disease getting worse after diagnosis. None of this is a test you can ask for. It is early research, and the people who did it are the first to say so.
What the evidence actually says
It is worth being precise about what this study is, because the headline could easily run ahead of it. This was a conference presentation, not a paper in a peer-reviewed journal. Conference findings are shared early so other researchers can question them. They have not yet been through the full checking process a journal applies. The study was also observational. It looked back at blood that had already been stored and compared groups. That can show a pattern. It cannot prove the pattern causes anything. The numbers are modest. Five hundred people, 100 of them healthy comparisons, is a reasonable size for this kind of deep immune analysis, but it is small for anything you would want to use as a screening test across a population. The computer model results are reported as AUC values. An AUC of 0.5 means the model is guessing. An AUC of 1.0 means it is perfect every time. Here the model scored 0.90 for telling future Crohn's apart from healthy comparisons, and 0.84 for future ulcerative colitis. For separating complicated Crohn's from less complicated Crohn's, about ten years ahead, it scored 0.85. Those are good scores for research. They are not the same as a reliable test for an individual person. The researchers set out their own conditions clearly. The signatures need to be checked in other groups of people who are larger, more varied, and followed forwards in time rather than looked at backwards. It also has to be shown that antibody testing adds something beyond what genetic, clinical and existing blood markers already tell doctors. And any future test would need to be accurate, affordable, repeatable, and actually improve how people fare. Dr Bourgonje put the next step plainly: "The next priority is to validate these signatures in independent, more diverse and prospectively followed populations." So: a genuinely interesting finding, honestly presented, a long way from the clinic.
Qurexa perspective
Crohn's disease and ulcerative colitis are long-term conditions, and that usually means long-term medicines. Many people with IBD take something every day to keep inflammation down and reduce the chance of a flare. Those medicines tend to work best when they are taken steadily, not in bursts. Running out, or leaving a gap because a repeat prescription did not arrive in time, is one of the commonest reasons treatment slips. This is the part of the picture we work on. Qurexa delivers prescriptions across Lincolnshire and supports people with staying on top of their medication, including the ordering, the timing and the awkward weeks when travel, work or a bad flare gets in the way. We mention it here for one reason only. Research like this study is about the far future of IBD care. Taking today's medicine as prescribed is the thing that makes a measurable difference now.
Practical advice
There is no blood test for future IBD, and there is nothing to ask your GP for off the back of this study. What is worth knowing is when gut symptoms deserve a proper look. The NHS suggests seeing a GP if you have: - diarrhoea that lasts more than seven days - blood in your poo - tummy pain that keeps coming back - unexplained weight loss - tiredness that does not lift Those symptoms have many possible causes, and most of them are not IBD. That is exactly why they are worth checking rather than guessing about. A few things help a GP appointment go further: Write it down before you go. Dates, how often, what the pain is like, what you have eaten, what makes it better or worse. A week of notes is more useful than trying to remember in the room. Say the quiet parts out loud. Blood, urgency and accidents are embarrassing to describe and genuinely important to mention. Ask what the plan is if things do not improve. A follow-up date is easier to arrange at the first appointment than to chase later. If you already have a diagnosis, the most useful habits are the dull ones: take your medicine as prescribed, go to your review appointments, and order repeat prescriptions before you reach the last few days of a pack. And if you are already in the system, you do not have to manage it alone. Crohn's & Colitis UK runs an information service and local groups, and your IBD nurse specialist, if you have one, is usually the fastest route to advice during a flare.
What to know
A study presented at UEG Week 2026 in Barcelona on 19 October found that antibody patterns in stored blood differed from healthy comparisons up to 10 years before people were diagnosed with Crohn's disease or ulcerative colitis. It used 2,000 samples from 500 people and measured 123,980 antibodies against around 357,000 targets. Computer models separated future Crohn's from healthy comparisons with an AUC of 0.90, and future ulcerative colitis with 0.84. It was a conference presentation, not a peer-reviewed paper, and the researchers say the findings must be confirmed in larger, more varied groups followed forwards in time. There is no test available and none is close. More than half a million people in the UK, about 1 in 123, live with Crohn's or colitis. If you have persistent diarrhoea, blood in your poo, recurring tummy pain or unexplained weight loss, see a GP rather than waiting it out. Sources: United European Gastroenterology, "Immune changes could signal inflammatory bowel disease up to 10 years before diagnosis", 19 October 2026, https://www.eurekalert.org/news-releases/1146879; ScienceDaily, "Your blood could reveal inflammatory bowel disease 10 years before diagnosis", 24 October 2026, https://www.sciencedaily.com/releases/2026/10/261023023713.htm; Crohn's & Colitis UK, "New research shows over 1 in 123 people in UK living with Crohn's or Colitis", https://www.crohnsandcolitis.org.uk/news-stories/news-items/new-research-shows-over-1-in-123-people-in-uk-living-with-crohn-s-or-colitis. This article is for general information and does not replace advice from a doctor, pharmacist or other qualified healthcare professional. If you are worried about gut symptoms, speak to your GP.
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