Chen P, et al. - In this prospective study, researchers ascertained if circulating microRNAs can be dependable biomarkers for inflammatory bowel disease (IBD) monitoring. By quantitative real-time polymerase chain reaction, serum levels of 17 candidate microRNAs were measured in a discovery cohort. Correlations were evaluated between relative microRNA levels and disease activity. In patients with Crohn's disease and ulcerative colitis, serum microRNA146b-5p (miR-146b-5p) expression was 2.87- and 2.72-fold higher, respectively, than in healthy controls. Overall, they suggested that miR-146b-5p could better reflect mucosal inflammation in IBD than C-reactive protein (CRP). In order to identify endoscopic activity in patients with Crohn's disease, the Crohn's disease classifier developed in this investigation could be useful.