Elevated levels of NE are detected in colonic mucosal tissue and plasma samples from UC patients and therefore measurement of NE abundance has previously been explored as a biomarker for IBD.35–37 However, NE abundance does reliably indicate active disease in IBD,38 and is inferior to other faecal markers, for example, calprotectin and lactoferrin.35 This is likely due to the concatenate release of endogenous NE inhibitors. This evidence concerns the gene LTF and inflammatory bowel disease.