Blood antibody patterns may flag inflammatory bowel disease a decade before diagnosis

Scientists have found that particular combinations of antibodies in a person's blood can signal the development of inflammatory bowel disease (IBD) around ten years before it is diagnosed. The research was published in the journal Gut and presented at the United European Gastroenterology meeting in Barcelona. It raises the prospect of identifying the condition far earlier than at present, when treatment usually begins only after symptoms appear and the gut has already been damaged.

What the study looked at

IBD is an immune condition that causes chronic inflammation of the digestive tract, leading to pain, diarrhoea and fatigue. Its two main forms are Crohn's disease and ulcerative colitis. At least 3.8 million people worldwide live with it. The exact cause is unknown, but an overactive or misfiring immune system, genetics and gut microbes can all contribute.

Researchers from Mount Sinai in New York, the Medical University of Vienna and the University Medical Centre Groningen analysed blood samples taken from US military personnel. They examined 2,000 samples from 500 people: 200 later developed Crohn's disease, 200 developed ulcerative colitis, and 100 developed neither. The samples were screened for antibodies against hundreds of thousands of protein fragments from bacteria, viruses, food and the body's own tissues.

Findings

People who went on to develop Crohn's disease more often had antibodies against the Epstein-Barr virus, which causes glandular fever. The differences were visible a decade before diagnosis, and the signal was strongest in those who later had more severe, complicated disease. Those who developed ulcerative colitis showed a different pattern, including antibodies against one of the body's own proteins.

Caution

Dr Arno Bourgonje of Groningen and Mount Sinai said this is not yet a test that can tell someone they will fall ill, but an important step towards earlier detection. The findings must be confirmed in other groups and show a link rather than proof that infections cause IBD. James Lindsay, a professor of gastroenterology at Barts Health who was not involved, said the techniques are "very much a research tool". The researchers hope IBD could follow the example of type 1 diabetes, where a blood test can identify risk before symptoms appear.