According to a new study published in Inflammatory Bowel Disease, a cohort of patients with clinically quiescent ulcerative colitis (UC) had a high prevalence of both endoscopic and histological disease activity, based on recently developed endoscopic and histological indices.
In addition, the investigators found that correlations between the endoscopy and histology findings were low, and constructed a multivariable model of clinical relapse with the indices, which had moderate predictive power.
With the Crohn’s and Colitis Foundation Clinical Research Alliance, Osterman and colleagues conducted the multicenter prospective cohort study to determine the prevalence of active endoscopic and histologic disease in patients with UC in clinical remission, the correlation between the endoscopic and histologic scores, and the power of these scores for predicting clinical relapse.
They assessed endoscopic activity using the Mayo endoscopic score (MES), ulcerative colitis endoscopic index of severity (UCEIS), and ulcerative colitis colonoscopic index of severity (UCCIS) and histological activity with the Riley index subcomponents, total Riley score, and basal plasmacytosis.
Adults with UC in clinical remission who were undergoing surveillance colonoscopy for dysplasia made up the cohort (n=100; male/female, 55%/45%). The average patient age (standard deviation) was 49.6 (13.0) years (range, 19.2-74.8 years).
More than half of the patients had an MES of 1 (56%), whereas 38% had a score of 2 or 3; only 5% had a score of 0. According to the UCEIS, most patients (79%) had mild activity (score 4-6); more severe activity (score 7-9) was observed in 15%. For the numerous indicators of histological disease, activity was observed in many patients.
All correlations between scores of endoscopic indices and histological subcomponents were low. The authors noted that the highest correlations were among the subcomponent architectural irregularity (MES ρ = 0.43; UCEIS ρ = 0.44), total Riley score (MES ρ = 0.35; UCEIS ρ = 0.37), and basal plasmacytosis (MES ρ = 0.36; UCEIS ρ = 0.36).
Nearly one fifth of the patients (19%) experienced clinical relapse over 1 year. The most predictive factor for clinical relapse was the Riley subcomponent architectural irregularity (P = .0076). The most predictive multivariable model incorporated the MES, architectural irregularity, and basal plasmacytosis (area under the receiver operating characteristic curve = 0.67; P = .0079).
Limitations of the study included a lack of examination the Nancy and Robarts Histological Indices, a limited design/sample size to assess predictors of relapse, and a relatively high proportion of patients from tertiary care centers who received immunosuppressive agents, which may reduce generalizability to a community setting or to those with mild UC.
“Larger prospective studies are needed to assess histological predictors of clinical relapse in quiescent UC,” wrote the authors.
Osterman MT, Scott FI, Fogt FF, et al. Endoscopic and Histological Assessment, Correlation, and Relapse in Clinically Quiescent Ulcerative Colitis (MARQUEE) [published online March 14, 2020]. Inflamm Bowel Dis. doi:10.1093/ibd/izaa048