Emerging role of novel biomarkers in the diagnosis of inflammatory bowel disease

Abstract

There is currently no gold standard test for the diagnosis of inflammatory bowel disease (IBD). Physicians must rely on a number of diagnostic tools including clinical and endoscopic evaluation as well as histologic, serologic and radiologic assessment. The real difficulty for physicians in both primary and secondary care is differentiating between patients suffering from functional symptoms and those with true underlying IBD. Alongside this, there is always concern regarding the possibility of a missed, or delayed diagnosis of ulcerative colitis (UC) or Crohn’s disease. Even once the diagnosis of IBD has been made, there is often uncertainty in distinguishing between cases of UC or Crohn’s. As a consequence, in cases of incorrect diagnosis, optimal treatment and management may be adversely affected. Endoscopic evaluation can be uncomfortable and inconvenient for patients. It carries significant risks including perforation and in terms of monetary cost, is expensive. The use of biomarkers to help in the diagnosis and differentiation of IBD has been increasing over time. However, there is not yet one biomarker, which is sensitive of specific enough to be used alone in diagnosing IBD. Current serum testing includes C-reactive protein and erythrocyte sedimentation rate, which are cheap, reliable but non-specific and thus not ideal. Stool based testing such as faecal calprotectin is a much more specific tool and is currently in widespread clinical use. Non-invasive sampling is of the greatest clinical value and with the recent advances in metabolomics, genetics and proteomics, there are now more tools available to develop sensitive and specific biomarkers to diagnose and differentiate between IBD. Many of these new advances are only in early stages of development but show great promise for future clinical use.

Keywords: Biomarkers, Inflammatory bowel disease, Ulcerative colitis, Crohn’s disease, Indeterminate colitis

Core tip: There is no gold standard test in the diagnosis of inflammatory bowel disease (IBD). Physicians must take into account clinical, endoscopic, and radiologic as well as serologic and histologic evidence in order to correctly diagnose their patients. Endoscopic evaluation is not only expensive, but is uncomfortable for patients and not without significant risk such as perforation. The use of biomarkers to help in the diagnosis and sub classification of IBD is an expanding area. In this review we touch on those non-invasive markers currently in clinical use before focusing on those more novel tests, with the potential to be highly useful in both diagnosis and differentiation of IBD.