Mucosal healing (MH) has become a major target in the management of ulcerative colitis (UC). Because repeat endoscopy is expensive and invasive, we aimed to evaluate fecal calprotectin (FC) as an alternative marker to predict MH in UC. Eighty patients with UC in clinical remission were consecutively included in a prospective observational study. FC was measured using a quantitative enzyme-linked immunosorbent assay. The colonic mucosa was assessed for endoscopic and histological measures of inflammatory status. Endoscopic and histological remission were defined according to the Mayo endoscopic subscore (MES) and Geboes score (GS), respectively. Deep remission was defined as a combination of the MES and GS. FC performance and cutoff values for identifying MH and deep remission were determined using contingency tables and receiver operator characteristic (ROC) and area under the curve (AUC) analysis. The median FC concentration in patients who met the criteria for deep remission (MES ≤1 and GS < 3.1) was 65.5 μg/g, while that in patients with disease activity was 389.6 μg/g (P = .025). A FC cutoff value of 100 μg/g, determined by the ROC analysis, resulted in sensitivity and specificity of 91.7% and 57.1%, respectively, for histological remission, and 82.4% and 60.9%, respectively, for deep mucosal remission. Positive correlations were detected between FC concentrations with the histologic (CC: 0.435; P < .001) and the combined endoscopic and histologic (CC: 0.413; P < .001) scores. FC can be used confidently as a noninvasive biomarker to predict deep remission in patients with UC in clinical remission when concentrations are below 100 μg/g.

BACKGROUND 1,3-beta-D-glucan (BG) is a ubiquitous cell wall component of gut micro-organisms. We hypothesized that the serum levels of BG could reflect active intestinal inflammation in patients with inflammatory bowel disease. AIM To determine whether the serum BG concentrations correlate with intestinal inflammation. METHODS A prospective observational study was performed in a tertiary referral center, from 2016 to 2019, in which serum BG was determined in 115 patients with Crohn’s disease (CD), 51 with ulcerative colitis (UC), and 82 controls using a photometric detection kit. Inflammatory activity was determined by ileocolonoscopy, histopathology, magnetic resonance enterography, and biomarkers, including fecal calprotectin (FC), C-reactive protein, and a panel of cytokines. The ability of BG to detect active vs inactive disease was assessed using the area under the receiver operating characteristic curve. In subgroup analysis, serial BG was used to assess the response to therapeutic interventions. RESULTS The serum BG levels were higher in CD patients than in controls ( P = 0.0001). The BG levels paralleled the endoscopic activity in CD patients and histologic activity and combined endoscopic and histologic activity in both CD and UC patients. The area under the curve (AUC) in receiver operating characteristic analysis to predict endoscopic activity was 0.694 [95% confidence interval (CI): 0.60-0.79; P = 0.001] in CD, and 0.662 (95%CI: 0.51-0.81; P = 0.066) in UC patients. The AUC in receiver operating characteristic analysis to predict histologic activity was 0.860 (95%CI: 0.77-0.95; P < 0.001) in CD, and 0.786 (95%CI: 0.57-0.99; P = 0.015) in UC patients. The cut-off values of BG for both endoscopic and histologic activity were 60 µg/mL in CD, and 40 µg/mL in UC patients. Performance analysis showed that the results based on BG of 40 and 60 µg/mL were more specific for predicting endoscopic activity (71.8% and 87.2% for CD; and 87.5% and 87.5% for UC, respectively) than FC (53.3% and 66.7% for CD; and 20% and 80% for UC, respectively); and also histologic activity (60.5% and 76.3% for CD; and 90.0% and 95.0% for UC, respectively) than FC (41.7% and 50.0% for CD; and 25% and 50% for UC, respectively). Regarding the clinical, endoscopic, and histologic activities, the BG levels were reduced following therapeutic intervention in patients with CD ( P < 0.0001) and UC ( P = 0.003). Compared with endoscopic (AUC: 0.693; P = 0.002) and histologic (AUC: 0.868; P < 0.001) activity, no significant correlation was found between serum BG and transmural healing based on magnetic resonance enterography (AUC: 0.576; P = 0.192)...