A newly developed stool-based test that rapidly detects signs of inflammatory bowel disease (IBD) could significantly improve how the condition is diagnosed and monitored, according to a new study. By directly identifying gut-specific inflammation, the test may reduce dependence on invasive and costly procedures.
The research has been published in Nature Biomedical Engineering.
How the New Optical Test Works
Scientists have created an optical tool that measures the activity of a molecule closely linked to intestinal inflammation in stool samples. Known as a luminescent reporter, the tool emits light when it detects the target molecule. Higher light signals indicate increased molecular activity and, therefore, greater levels of gut inflammation.
As a result, the technique offers a rapid and sensitive method to assess disease activity using a non-invasive sample.
Current Challenges in Diagnosing IBD
IBD is a chronic condition in which the immune system mistakenly attacks the digestive tract, causing persistent inflammation. At present, doctors largely rely on colonoscopy—a procedure that uses a small camera to examine the bowel—to diagnose and monitor the disease.
While stool tests are already in use, they typically measure general inflammatory markers such as fecal calprotectin. However, a positive result does not pinpoint the exact source of inflammation and often requires further invasive testing.
Targeting Gut-Specific Inflammation
To overcome this limitation, researchers from the University of Edinburgh analysed gut tissue from patients with IBD. They found significantly higher levels of an enzyme called granzyme A (GzmA) in inflamed tissue compared with non-inflamed samples.
GzmA is released by T cells, a type of white blood cell that normally protects the body by targeting infections or abnormal cells. In IBD, however, these cells become overactive and mistakenly attack the gut, triggering inflammation and tissue damage.
Testing the Luminescent Reporter
Building on these findings, the research team developed a luminescent reporter capable of detecting GzmA activity in stool samples. They tested the tool on 150 samples collected from both individuals with IBD and healthy participants.
Notably, combining the new reporter with standard fecal calprotectin testing proved more effective in identifying IBD than using calprotectin levels alone.
Implications for Diagnosis and Patient Care
As reported by medicalxpress, researchers believe that the ability to detect gut-specific inflammation marks an important advance in IBD diagnostics. However, they caution that further studies are required before the test can be adopted in routine clinical practice.
Looking ahead, the technology could also enable more precise disease monitoring, helping clinicians assess how patients respond to different treatments in real time.
Commercial Development and Future Applications
The luminescent reporter technology will form part of the intellectual assets of IDXSense, a new company currently spinning out of the University of Edinburgh with support from Edinburgh Innovations, the university’s commercialisation arm.
The team aims to develop non-invasive, in-vitro diagnostic devices that address a major unmet need in IBD care.
Expert Perspectives
Professor Marc Vendrell, study lead from the University of Edinburgh’s Institute for Regeneration and Repair, said the tool’s speed and sensitivity could accelerate research into immune mechanisms driving IBD. He added that, in the future, such optical tools could also support more personalised treatment strategies for patients.
Lizzie Withington, Director of Venture Creation at Edinburgh Innovations, noted that the IDXSense team is actively designing, developing, and manufacturing novel diagnostic devices for IBD. She added that the group is seeking partners to help translate the technology into improved health outcomes for patients living with the disease.