Endoscopic scoring systems for inflammatory bowel disease: pros and cons

Abstract

Endoscopy plays a pivotal role for diagnosis and assessment of disease activity and extent in patients with inflammatory bowel diseases. International guidelines recommend the use of endoscopic scoring systems for evaluation of the prognosis and efficacy of medical treatments. Ideal scoring systems are easy to use, reproducible, reliable, responsive to changes, and validated in different clinical settings in order to guide therapeutic strategies. However, currently available endoscopic scoring systems often appear as complex for routine endoscopy and suffer from insufficient interobserver agreement and lack of formal validation which often limit their use in clinical trials. Here, we describe the role of endoscopic scoring systems in inflammatory bowel diseases focusing on pros and cons in the era of advanced endoscopic imaging and mucosal healing.

Keywords::

• advanced endoscopic imaging
• colonoscopy
• Crohn’s disease
• disease activity indices
• endoscopic disease activity
• inflammatory bowel disease
• mucosal activity
• mucosal healing
• ulcerative colitis

Disclaimer

All authors were involved in the concept development, research and writing of this article.

Financial & competing interests disclosure

GE Tontini has gained a grant from the Italian Group for the study of IBD (IG-IBD) supporting his research works at the Department of Medicine I, University of Erlangen-Nuremberg. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Endoscopy plays a pivotal role in the management of inflammatory bowel disease. The use of endoscopic scoring systems improves the endoscopic reproducibility and reliability, thereby allowing the comparison between different clinical trials.

• Interobserver variability in assessing the presence of parameter such as friability or ulcer depth, as well as in the final scoring is a matter capable of remarkable impact in trials’ results and clinical strategies.

• The endoscopic assessment of mucosal involvement by means of validated scoring systems is the most reliable outcome of disease activity in patients with nonstricturing, nonpenetrating Crohn’s disease (CD).

• In clinical settings, experience and training tools could substantially improve scoring agreement, while in research trials’, central review appears as a good option to preserve results’ reliability and increase statistical power.

• Validated scoring systems for either ulcerative colitis or CD are now available, and impending researches are expected to define and validate thresholds values for disease activity degree and response to therapy.

• Currently, validated endoscopic scoring systems are complex, time-consuming and require analysis ad hoc, which often hampers their assessment a posteriori and their mutual comparison.

• There is no widely accepted definition of mucosal healing for both CD and ulcerative colitis, nor well-substantiated evidence referring to complete normalization of gut mucosa as a more cost-effective endpoint compared with persisting subtle lesions such as slight erythema, edema and granularity.

• Advanced endoscopic imaging techniques are practical tools to enhance in real-time mucosal subtle details, thereby potentially improving endoscopic assessment of disease activity as well as the accuracy of the scoring systems.