Issue 05

Clinical Question

Can a novel serum-based protein test accurately identify endoscopic remission in Crohn’s disease?

Editor’s Bottom Line

This new serologic panel offers a promising alternative to colonoscopy for assessing disease activity in patients with Crohn’s disease.

Reference

D’Haens G, Kelly O, Battat R, et al. Development and Validation of a Test to Monitor Endoscopic Activity in Patients with Crohn’s Disease Based on Serum Levels of Proteins. Gastroenterol. 2020;158(3):515–26.e10; https://doi.org/10.1053/j.gastro.2019.10.034

Synopsis

Researchers at multiple international sites set out to develop a test to identify remission in Crohn’s disease (CD) patients based on serum levels of 13 proteins that have previously been shown to correlate with mucosal inflammation. They validated an Endoscopic Healing Index (EHI) using blood samples from 116 patients with early-stage CD who had not received biologics and 195 patients with established disease previously treated with biologic drugs. EHI scores were correlated with the Simple Endoscopic Score for CD (SES-CD) and Crohn’s Disease Endoscopic Index of Severity (CDEIS). EHI’s diagnostic accuracy was also compared to serum C-reactive protein (CRP) and fecal calprotectin, which the authors noted is measured in less than 2% of IBD patients in the United States.

Results showed that higher EHI scores correlated with more severe endoscopic disease activity. EHI had high accuracy in identifying endoscopic remission in those with early-stage disease (Area Under the Receiver Operating Characteristics [AUROC]: 0.962; 95% Confidence Interval [CI], 0.942–0.982) and moderate accuracy in identifying remission in those with established disease (AUROC: 0.693; 95% CI, 0.619–0.767), regardless of disease location or phenotype. A cut-off of 20 points on the EHI was 97% and 83% sensitive for identifying remission among those with early-stage and established disease, respectively, and was 69% and 37% specific. A cut-off of 50 points on the EHI was 100% and 87.8% sensitive in detecting endoscopic remission in the two groups, respectively, and 37.3% and 30% specific. The EHI was more accurate than CRP testing in identifying remission in patients with early-stage disease (AUROC for CRP: 0.876; P<.001 for EHI vs. CRP) but not with established disease. The EHI was not significantly more accurate than fecal calprotectin measurement in identifying remission.

Details

Study Design: Prospective validation cohort
Funding: The Litwin Pioneers Program Crohn’s and Colitis Foundation; Prometheus; San Diego Digestive Diseases Research Center; the American Gastroenterological Association
Allocation: Not applicable
Setting: Multicenter
Level of Evidence: 1b (Oxford Levels of Evidence)

The summary and conclusion in this issue of E-mentoring in IBD pertains to the manuscript(s) being reviewed, and should be considered in the context of what is already known surrounding the topic and incorporated into practice as deemed appropriate by the individual learner.