Beyond endoscopic mucosal healing in UC: histological remission better predicts corticosteroid use and hospitalisation over 6 years of follow-up

Impact of completely histological remission on reducing flare-ups in moderate-to-severe, biologics-experienced ulcerative colitis patients with endoscopic remission

BACKGROUND/PURPOSE

Endoscopic remission is presently recognized as the standard therapeutic target in the treatment of ulcerative colitis (UC). However, achieving histological remission is increasingly viewed as a pivotal objective. This study investigates the effects of attaining completely histological remission on the clinical outcomes for UC patients with a high disease burden who have already reached endoscopic remission. This is the inaugural study to concentrate on this specific patient demographic.

METHODS

This retrospective cohort study enrolled moderate-to-severe, biologics-experienced UC patients with completely endoscopic remission (Mayo endoscopic subscore of 0) between June 2017 and October 2023 at Chang Gung Memorial Hospital, Linkou. Patients were classified into histological remission (HR) and non-histological remission (non-HR) groups based on the Nancy index (NI). HR was defined as an NI score of 0, with all other patients categorized as non-HR. The definition of flare-ups was based on both clinical and endoscopic evidence. Comparative analyses focused on baseline characteristics and clinical outcomes at follow-up.

RESULTS

A total of 42 patients (HR group: 23, non-HR group: 19) were included. The average follow-up duration was 17.6 months. Baseline characteristics were comparable between the groups. At the end of follow-up, the HR group showed a significantly lower rate of acute flare-ups (26.1% vs. 68.4%, P = 0.006). Although not statistically significant, the HR group also experienced fewer emergency department visits and hospital admissions.

CONCLUSIONS

For moderate-to-severe, biologics-experienced UC patients in endoscopic remission, achieving completely histological remission is associated with a substantial reduction in flare-ups, suggesting its potential as a valuable therapeutic target.

Fecal calprotectin and platelet count predict histologic disease activity in pediatric ulcerative colitis: results from a projection-predictive feature selection

Especially for pediatric patients, proxies of mucosal inflammation are needed. The Pediatric Ulcerative Colitis Activity Index (PUCAI) has been established to predict clinical and endoscopic disease activity. However, histologic inflammation might persist. We applied a special variable selection technique to predict histologic healing in pediatric ulcerative colitis (UC) as parsimoniously (but still as precisely) as possible. The retrospective analysis included data from two study cohorts, comprising 91 visits from 59 pediatric patients with UC. A Bayesian ordinal regression model was used in combination with a projection-predictive feature selection (PPFS) to identify a minimal subset of clinical and laboratory parameters sufficient for the prediction of histologic disease activity. Following the PPFS, CEDATA-GPGE patient registry data were analyzed to investigate the relevance of the selected predictors in relation to PUCAI and Physician Global Assessment (PGA) in up to 6697 patient visits. Fecal calprotectin (FC) and platelet count were identified as the minimal subset of predictors sufficient for prediction of histologic disease activity in pediatric UC. FC and platelet count also appeared to be associated with increasing disease activity as measured by PUCAI and PGA in the CEDATA-GPGE registry. Based on the selected model, predictions can be performed with a Shiny web app.  Conclusion: Our statistical approach constitutes a reproducible and objective tool to select a minimal subset of the most informative parameters to predict histologic inflammation in pediatric UC. A Shiny app shows how physicians may predict the histologic activity in a user-friendly way using FC and platelet count. To generalize the findings, further prospective studies will be needed. What is Known: • Histologic healing is a major endpoint in the therapy of ulcerative colitis (UC). • The PUCAI score has been established to predict disease activity in pediatric UC but is not suitable for the prediction of histologic healing. What is New: • Our Bayesian ordinal regression model in combination with a projection-predictive feature selection is a reproducible and objective tool to select the minimal subset of clinical and laboratory parameters to predict histologic inflammation in pediatric UC. • Histologic inflammation in pediatric UC can be non-invasively predicted based on the combination of fecal calprotectin levels and platelet count.

Achievement of Clinical, Endoscopic, and Histological Outcomes in Patients with Ulcerative Colitis Treated with Etrasimod, and Association with Faecal Calprotectin and C-reactive Protein: Results From the Phase 2 OASIS Trial

BACKGROUND AND AIMS

Etrasimod is an oral, once-daily, selective sphingosine 1-phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active ulcerative colitis [UC]. This post-hoc analysis of the phase 2 OASIS trial [NCT02447302] evaluated its efficacy for endoscopic improvement-histologic remission [EIHR] and assessed correlation between faecal calprotectin [FCP] and C-reactive protein [CRP] levels with efficacy outcomes.

METHODS

In total, 156 adults with moderately to severely active UC received once-daily etrasimod (1 mg [n = 52]; 2 mg [n = 50]) or placebo [n = 54] for 12 weeks. Clinical, endoscopic, and histologic variables were evaluated at baseline and Week 12. EIHR was defined as achievement of endoscopic improvement [endoscopic subscore ≤ 1, without friability] and histologic remission [Geboes score < 2.0]. Outcomes included the relationships between FCP and CRP concentration and clinical, endoscopic, and histologic variables.

RESULTS

Achievement of EIHR was significantly higher in patients who received etrasimod 2 mg versus placebo [19.5% vs 4.1%; Mantel-Haenszel estimated difference, 15.4%; p = 0.010]. In the etrasimod 2 mg group, median FCP and CRP levels at Week 12 were significantly lower in patients who achieved clinical remission, endoscopic improvement, histologic remission, and EIHR versus patients who did not [all p < 0.05]. An FCP concentration cutoff of 250 µg/g achieved optimum sensitivity and specificity for efficacy, including EIHR [0.857 and 0.786, respectively; κ coefficient, 0.3584]. Higher proportions of patients with FCP ≤ 250 µg/g achieved efficacy outcomes at Week 12 versus patients with FCP > 250 µg/g.

CONCLUSIONS

Etrasimod was effective for inducing EIHR in patients with UC. FCP and CRP may be useful, noninvasive biomarkers to monitor treatment response.

CLINICALTRIALS.GOV NUMBER

NCT02447302.

How close are we to a success stratification tool for improving biological therapy in ulcerative colitis?

INTRODUCTION

Biological therapies have become the standard treatment for ulcerative colitis (UC). However, clinical remission rates post-induction therapy remain modest at 40-50%, with many initial responders losing response over time. Current treatment strategies frequently rely on a 'trial and error' approach, leading to prolonged periods of ineffective and costly therapies for patients, accompanied by associated treatment complications.

AREA COVERED

This review discusses current evidence on risk stratification tools for predicting therapeutic efficacy and minimizing adverse events in UC management. Recent studies have identified predictive factors for biologic therapy response. In the context of personalized medicine, the goal is to identify patients at high risk of progression and complications, as well as those likely to respond to specific therapies. Essential risk stratification tools include clinical decision-making aids, biomarkers, genomics, multi-omics factors, endoscopic, imaging, and histological assessments.

EXPERT OPINION

Employing risk stratification tools to predict therapeutic response and prevent treatment-related complications is essential for precision medicine in the biological management of UC. These tools are necessary to select the most suitable treatment for each individual patient, thereby enhancing efficacy and safety.

Histologic Disease Persists beyond Mucosal Healing and Could Predict Reactivation in Ulcerative Colitis

Mucosal healing (MH) is the main target in ulcerative colitis (UC) treatment. Even if MH lowers the risk of disease reactivation, some patients still relapse. Histologic activity (HA) beyond MH could explain these cases. This study aims to assess how many patients with MH have HA and which lesions are associated with relapse. We retrospectively enrolled UC patients showing MH, expressed as a Mayo Endoscopic Subscore (MES) of 0 and 1 upon colonoscopy. We reviewed the histological reports of biopsies evaluating the presence of typical lesions of UC and assessed the number of clinical relapses after 12 months. Among 100 enrolled patients, 2 showed no histological lesions. According to univariate analysis, patients with a higher number of histological lesions at the baseline had a higher risk of relapse (OR 1.25, p = 0.012), as well as patients with basal plasmacytosis (OR 4.33, p = 0.005), lamina propria eosinophils (OR 2.99, p = 0.047), and surface irregularity (OR 4.70, p = 0.010). However, in the multivariate analysis, only basal plasmacytosis (OR 2.98, p = 0.050) and surface irregularity (OR 4.50, p = 0.024) were confirmed as risk factors for disease reactivation. HA persists in a significant percentage of patients with MH. Despite the presence of MH, patients with basal plasmacytosis and surface irregularity have a higher risk of relapse.

Effects of Thiopurine Withdrawal on Vedolizumab-Treated Patients With Ulcerative Colitis: A Randomized Controlled Trial

BACKGROUND & AIMS

The impact of thiopurine de-escalation while on vedolizumab versus continuing thiopurine therapy in ulcerative colitis (UC) is unclear. We aimed to determine the effect of thiopurine withdrawal for patients with UC in remission on vedolizumab.

METHODS

This multicenter randomized controlled trial recruited UC patients on vedolizumab 300 mg intravenously every 8 weeks and a thiopurine. Patients in steroid-free clinical remission for ≥6 months and endoscopic remission/improvement (Mayo endoscopic subscore ≤1) were randomized 2:1 to withdraw or continue thiopurine. Primary outcome was comparing week 48 vedolizumab trough concentrations. Secondary outcomes were clinical relapse (partial Mayo score ≥3 and fecal calprotectin >150 μg/g or increase in Mayo endoscopic subscore ≥1 from baseline), fecal calprotectin remission (<150 μg/g), C-reactive protein remission (<5 mg/L), centrally read endoscopic remission (Mayo endoscopic subscore = 0), histologic remission (Nancy index = 0), histo-endoscopic remission, and adverse events.

RESULTS

In total, 62 patients were randomized to continue (n = 20) or withdraw (n = 42) thiopurine. At week 48, vedolizumab trough concentrations were not significantly different between continue and withdrawal groups (14.7 μg/mL, interquartile rate [IQR], 12.3-18.5 μg/mL versus 15.9 μg/mL, IQR, 10.1-22.7 μg/mL, respectively, P = 0.36). The continue group had significantly higher fecal calprotectin remission (95.0%, 19/20 versus 71.4%, 30/42; P = .03), histologic remission (80.0%, 16/20 versus 48.6%, 18/37; P = .02), and histo-endoscopic remission (75.0%, 15/20 versus 32.4%, 12/37; P = .002) than the withdrawal group. Histologic activity (hazard ratio [HR], 15.5; 95% confidence interval [CI], 1.6-146.5; P = .02) and prior anti-tumor necrosis factor exposure (HR, 6.5; 95% CI, 1.3-33.8; P = .03) predicted clinical relapse after thiopurine withdrawal.

CONCLUSIONS

Thiopurine withdrawal did not affect vedolizumab trough concentrations. However, it may increase fecal calprotectin, histologic, and histo-endoscopic activity. Histologic activity and prior anti-tumor necrosis factor exposure may predict disease relapse on thiopurine withdrawal for patients using vedolizumab for UC. Australian and New Zealand Trial Registry, number ACTRN12618000812291.

Disease clearance in ulcerative colitis: A new therapeutic target for the future

Advancements in murine modeling systems for ulcerative colitis have diversified our understanding of the pathophysiological factors involved in disease onset and progression. This has fueled the identification of molecular targets, resulting in a rapidly expanding therapeutic armamentarium. Subsequently, management strategies have evolved from symptomatic resolution to well-defined objective endpoints, including clinical remission, endoscopic remission and mucosal healing. While the incorporation of these assessment modalities has permitted targeted intervention in the context of a natural disease history and the prevention of complications, studies have consistently depicted discrepancies associated with ascertaining disease status through clinical and endoscopic measures. Current recommendations lack consideration of histological healing. The simultaneous achievement of clinical, endoscopic, and histologic remission has not been fully investigated. This has laid the groundwork for a novel therapeutic outcome termed disease clearance (DC). This article summarizes the concept of DC and its current evidence.

Histological Disease Activity as Predictor of Clinical Relapse, Hospitalization, and Surgery in Inflammatory Bowel Disease: Systematic Review and Meta-Analysis

BACKGROUND

The clinical impact of histological remission on short- and long-term clinical outcomes in patients with inflammatory bowel disease (IBD) is not well established. We assessed risk of clinical relapse, hospitalization, and need for surgery in patients achieving histological remission in comparison with active histological disease.

METHODS

A systematic review was conducted using MEDLINE, Scopus, Cochrane CENTRAL, EMBASE, and conference abstracts from inception to November 2022. Our main outcome was the rate of clinical relapse in patients with IBD who reached histological remission vs patients with active histological disease. Secondary outcomes were clinical complications of IBD such as hospitalization and need for surgery. The endpoints were investigated at 2 time points, 6 to 12 months (short term) and >12 months (long term).

RESULTS

Short-term outcome analysis showed that the risk of clinical relapse was significantly higher in ulcerative colitis patients with active histological disease in comparison with patients at histological remission (risk ratio [RR], 2.41; 95% confidence interval [CI], 1.69-3.44; P < .01). The risk of hospitalization in ulcerative colitis patients was not significant among the 2 groups (RR, 4.22; 95% CI, 0.91-19.62; P = .07). Long-term outcome analysis demonstrated that the risk of clinical relapse (RR, 2.07; 95% CI, 1.55-2.76; P < .01), need for surgery (RR, 3.14; 95% CI, 1.53-6.45; P < .01), and hospitalization (RR, 2.52; 95% CI, 1.59-4.00; P < .01) was significantly higher in patients with active histological disease.

CONCLUSIONS

Histological remission in IBD represents an important therapeutic goal that is not yet routinely pursued in clinical practice. In our study, patients who achieved histological remission have more favorable outcomes than those with active histological disease in ulcerative colitis.

Safety of full bowel preparation and colonoscopy in elderly patients with ulcerative colitis: A real-world multicenter retrospective cohort study

Background

The number of elderly patients with ulcerative colitis (UC) has been increasing worldwide. Complications are common in elderly patients who undergo colonoscopy, raising doubts about whether colonoscopy should be performed in the same way in this age group as in younger patients. The aim of this study was to determine the safety of full bowel preparation and colonoscopy in elderly patients with UC.

Methods

We retrospectively reviewed a cohort of patients with UC who had visited any of the 12 hospitals and were registered in our inflammatory bowel disease database. We compared complications associated with colonoscopy and bowel preparation and relapse of UC after colonoscopy in 133 patients aged ≥65 years with UC (the elderly group) and 116 randomly selected patients aged <65 years with UC (the non-elderly group).

Results

Nine elderly patients were not referred for colonoscopy by their physicians because of poor performance status or advanced age. There was no significant between-group difference in the complication rate (p = 0.57) or frequency of relapse of UC after colonoscopy (p = 0.67).

Conclusions

The findings of this study indicate that colonoscopy can be performed as safely in elderly patients with UC as in their younger counterparts. However, our results also indicate that colonoscopy is often avoided in elderly patients, possibly because of concerns about safety.

Histological healing induced by tofacitinib in ulcerative colitis: A multicentre study

BACKGROUND

While the efficacy of tofacitinib to induce and maintain clinical and endoscopic remission is well established in ulcerative colitis (UC), little is known about its efficacy to induce histological remission.

METHODS

We conducted a retrospective multicentric cohort study. UC patients ≥ 16 years treated by tofacitinib in whom histological activity has been evaluated before and after induction were eligible. The primary endpoint was the histological remission at the end of induction, assessed by the Nancy index and the epithelial neutrophilic infiltrate.

RESULTS

A total of 42 patients with UC (93% previously exposed to an anti-TNF and 81% to vedolizumab) were included between July 2018 and April 2022 and were followed for a median duration of 84 weeks [IQR, 35-134]. At the end of induction period (whether prolonged or not), 19% and 24% of patients achieved histological remission, using the Nancy index and the epithelial neutrophilic infiltrate, respectively. Survival without tofacitinib discontinuation was significantly longer in patients without epithelial neutrophilic infiltrate at the end of induction (whether prolonged or not) compared with patients with epithelial neutrophilic infiltrate (p = 0.036).

CONCLUSION

Tofacitinib induced histological remission in one fifth to one quarter of patients with UC who have previously failed anti-TNF or/and vedolizumab after induction (whether prolonged or not).

Etrolizumab as an induction and maintenance therapy for ulcerative colitis: A systematic review and meta-analysis of randomized controlled trials

Background and Aim

Etrolizumab is a gut-targeted anti-β7 integrin monoclonal antibody. However, the evidence of etrolizumab efficacy and safety in ulcerative colitis remains inconclusive. Therefore, we aim to evaluate the safety and efficacy of etrolizumab as an induction and maintenance therapy for active moderate to severe ulcerative colitis.

Methods

We synthesized randomized controlled studies (RCTs) from MEDLINE, Scopus, EMBASE, PubMed, Web of Science, and Cochrane Library until April 2023. The risk ratio (RR) for dichotomous outcomes with the corresponding 95% confidence interval (CI) was used. The study protocol was registered in PROSPERO with ID: CRD42023437040.

Results

Five RCTs with 1849 participants were included. The etrolizumab group had a significant clinical response (RR: 1.28 with 95% CI [1.08, 1.51], P = 0.005), clinical remission rates during the induction phase (RR: 2.47 with 95% CI [1.48, 4.11], P = 0.0005), compared with the placebo group in ulcerative colitis; however, there was no statistically significant difference between the two groups, regarding the corticosteroids-free remission rate (RR: 1.92 with 95% CI [0.94, 3.92], P = 0.07). Moreover, endoscopic improvement, endoscopic remission, and histologic remission rates were observed more in the etrolizumab group during both the induction and maintenance phases. For safety outcomes, etrolizumab was significantly safer, but any adverse event was higher in the etrolizumab group than in the placebo.

Conclusion

Etrolizumab shows its effectiveness as both an induction and maintenance therapy for moderate or severe UC. The findings demonstrate its positive impact on clinical, endoscopic, and histologic remission rates. Regarding safety, other than any side effects, etrolizumab showed a good safety than a placebo.

Present and future of endoscopy precision for inflammatory bowel disease

Several advanced imaging techniques are now available for endoscopists managing inflammatory bowel disease (IBD) patients. These tools, including dye-based and virtual chromoendoscopy, probe-based confocal laser endomicroscopy and endocytoscopy, are increasingly innovative applications in clinical practice. They allow for a more in-depth and refined evaluation of the mucosal and vascular bowel surface, getting closer to histology. They have demonstrated a remarkable ability in assessing intestinal inflammation, histologic remission, and predicting relapse and favorable long-term outcomes. In addition, the future application of molecular endoscopy to predict biological drug responses has yielded preliminary but encouraging results. Furthermore, these techniques are crucial in detecting and characterizing IBD-related dysplasia, assisting endoscopic mucosal resection and submucosal dissection towards a surgery-sparing approach. Artificial intelligence (AI) holds great potential in this promising landscape, as it can provide an objective and reproducible assessment of inflammation and dysplasia. Moreover, it can improve the prediction of outcomes and aid in subsequent therapeutic decision-making. This review aims to summarize the promising role of state-of-the-art advanced endoscopic techniques and related AI-enabled models for managing IBD, paving the way for precision medicine.

Identification of immune cell markers associated with ulcerative colitis histological disease activity in colonic biopsies

AIMS

Accurate determination of histological activity in ulcerative colitis (UC) is essential given its diagnostic and prognostic importance. Data on the relationship between histology and immune cell markers are limited. We aimed to evaluate the association between histological disease activity and immune cell marker concentration in colonic biopsies from patients with UC.

METHODS

Sigmoid colon biopsies from 20 patients with UC were retrospectively assessed using the Robarts Histopathology Index (RHI). Targeted mass spectrometry determined the concentration of 18 immune cell markers (cluster of differentiation (CD) 4, CD8, CD19, CD20, CD40, CD56, CD68, CD103, forkhead box p3 (FOXP3), human leucocyte antigen, DR alpha chain (HLA-DRA), interleukin 10 (IL-10), IL-23 subunit alpha (IL-23A), IL-23 receptor (IL-23R), IL-2 receptor alpha chain (IL-2RA), Ki67, lymphocyte-activation gene 3 (LAG-3), programmed cell death protein 1 (PD-1) and PD ligand 1 (PD-L1)). The association between RHI score and immune cell marker concentration was quantified using Spearman's rank correlation coefficient (ρ) and related 95% CIs.

RESULTS

Fourteen of the 18 immune cell marker proteins were detected, with tissue concentration ranging from 0.003 to 11.53 fmol/µg. The overall RHI score was positively correlated with CD19, CD20, CD40, FOXP3, LAG-3, PD-1 and PD-L1 concentration (ρ=0.596-0.799) and negatively correlated with CD56 concentration (ρ=-0.460). There was no significant association between RHI score and CD4, CD8, CD68, CD103, HLA-DRA or Ki67 concentration.

CONCLUSIONS

This study provides insight into the correlation between immune cell marker expression and histological disease activity and the possible molecular and immunological determinants underlying microscopic disease activity in UC.

Determining the optimal treatment target in patients with ulcerative colitis: rationale, design, protocol and interim analysis for the randomised controlled VERDICT trial

INTRODUCTION

Symptoms, endoscopy and histology have been proposed as therapeutic targets in ulcerative colitis (UC). Observational studies suggest that the achievement of histologic remission may be associated with a lower risk of complications, compared with the achievement of endoscopic remission alone. The actiVE ulcerative colitis, a RanDomIsed Controlled Trial (VERDICT) aims to determine the optimal treatment target in patients with UC.

METHODS AND ANALYSIS

In this multicentre, prospective randomised study, 660 patients with moderate to severe UC (Mayo rectal bleeding subscore [RBS] ≥1; Mayo endoscopic score [MES] ≥2) are randomly assigned to three treatment targets: corticosteroid-free symptomatic remission (Mayo RBS=0) (group 1); corticosteroid-free endoscopic remission (MES ≤1) and symptomatic remission (group 2); or corticosteroid-free histologic remission (Geboes score <2B.0), endoscopic remission and symptomatic remission (group 3). Treatment is escalated using vedolizumab according to a treatment algorithm that is dependent on the patient's baseline UC therapy until the target is achieved at weeks 16, 32 or 48. The primary outcome, the time from target achievement to a UC-related complication, will be compared between groups 1 and 3 using a Cox proportional hazards model.

ETHICS AND DISSEMINATION

The study was approved by ethics committees at the country level or at individual sites as per individual country requirements. A full list of ethics committees is available on request. Study results will be disseminated in peer-reviewed journals and at scientific meetings.

TRIAL REGISTRATION NUMBER

EudraCT: 2019-002485-12; NCT04259138.

In-Depth Assessment of Endoscopic Remission in Inflammatory Bowel Disease Treated by Anti-TNF or Vedolizumab

BACKGROUND AND AIMS

Confocal endomicroscopy is a technique allowing the in vivo assessment of the superficial layers of the mucosa. Preliminary studies have already suggested its added value in the assessment of endoscopic remission in inflammatory bowel disease. However, most of these studies were performed on patients still having incomplete mucosal healing. Our aim was to disclose persisting endomicroscopic anomalies in patients with full endoscopic remission and to compare them between vedolizumab- and anti-tumor necrosis factor-treated patients.

METHODS

We screened patients with Crohn's disease (CD) or ulcerative colitis (UC) treated for more than 6 months with biologic therapy, and being in steroid-free clinical and biological remission. White light endoscopy and probe-based confocal laser endomicroscopy (pCLE) analysis were performed in the ileum, right colon, transverse colon, left colon, and rectum. Full endoscopic remission was defined by a Mayo endoscopic score of 0 in UC and no remaining ulcer or erosion in CD. Patients were prospectively followed up and clinical relapses were recorded.

RESULTS

Seventy-two CD and UC patients treated by biologic therapy and in clinical and biological remission were screened. A total of 37 were also in full endoscopic remission and were included in our study; 183 intestinal segments were analyzed. We found residual pCLE anomalies in most of the patients. These anomalies were not significantly associated with any demographic or clinical characteristic including the treatment received, nor were they associated with histological parameters, levels of C-reactive protein or fecal calprotectin. Among the 37 patients, 7 (18.9%) relapsed over a median follow-up of 33.7 months. The risk of relapse was not associated with any clinical, biological, histologic, or pCLE feature at baseline.

CONCLUSION

Despite endoscopic, biological, and even histological remission, we found a high prevalence of endomicroscopic abnormalities, which were not different between anti-tumor necrosis factor- and vedolizumab-treated patients. The clinical significance of these anomalies remains to be clarified.

Composite Assessment Using Intestinal Ultrasound and Calprotectin Is Accurate in Predicting Histological Activity in Ulcerative Colitis: A Cohort Study

BACKGROUND

Beyond endoscopic remission, histological remission in ulcerative colitis (UC) is predictive of clinical outcomes. Intestinal ultrasound (IUS) may offer a noninvasive surrogate marker for histological activity; however, there are limited data correlating validated ultrasound and histological indices.

AIM

Our aim was to determine the correlation of IUS activity in UC with a validated histological activity index.

METHODS

Twenty-nine prospective, paired, same-day IUS/endoscopy/histology/fecal calprotectin (FC) cases were included. Intestinal ultrasound activity was determined using the Milan Ultrasound Criteria, histological activity using the Nancy Histological Index, endoscopic activity using Mayo endoscopic subscore and Ulcerative Colitis Endoscopic Index of Severity, and clinical activity using the Simple Clinical Colitis Activity Score.

RESULTS

Histological activity demonstrated a significant linear association with overall IUS activity (coefficient 0.14; 95% CI, 0.03-0.25; P = .011). Intestinal ultrasound activity was also significantly associated with endoscopic activity (0.32; 95% CI, 0.14-0.49; P < 0.001), total Mayo score (0.31; 95% CI, 0.02-0.60; P = .036) but not FC (0.10; 95% CI, -0.01 to 0.21; P = .064) or clinical disease activity (0.04; 95% CI, -0.21 to 0.28; P = .768). A composite of IUS and FC showed the greatest association (1.31; 95% CI, 0.43-2.18; P = .003) and accurately predicted histological activity in 88% of cases (P = .007), with sensitivity of 88%, specificity 80%, positive predictive value 95%, and negative predictive value 57%.

CONCLUSIONS

Intestinal ultrasound is an accurate noninvasive marker of histological disease activity in UC, the accuracy of which is further enhanced when used in composite with FC. This can reduce the need for colonoscopy in routine care by supporting accurate point-of-care decision-making in patients with UC.

Considering Histologic Remission in Ulcerative Colitis as a Long-Term Target

Monitoring disease activity in inflammatory bowel disease (IBD) is challenging since clinical manifestations do not represent reliable surrogates for an accurate reflection of the inflammatory burden. Endoscopic remission had been the most significant endpoint target in the last years; nevertheless, a remarkable proportion of patients continue to relapse despite a normal-appearing mucosa, highlighting that endoscopy may underestimate the true extent of the disease. A subtle hint of the importance that histology plays in the long-term course of the disease has been endorsed by the STRIDE-II consensus, which recommends considering histologic healing for ulcerative colitis (UC), even though it is not stated to be a compulsory formal target. It is a continuum-changing paradigm, and it is almost a certainty that in the near future, histologic healing may become the new formal target for ulcerative colitis. It must be emphasized that there is great heterogeneity in defining histological remission, and the main criteria or cut-off values for inflammatory markers are still in an ill-defined area. The complexity of some histologic scores is a source of confusion among clinicians and pathologists, leading to low adherence in clinical practice when it comes to a homogenous histopathological report. Therefore, a standardized and more practical approach is urgently needed.

Comparison of Endoscopic and Artificial Intelligence Diagnoses for Predicting the Histological Healing of Ulcerative Colitis in a Real-World Clinical Setting

Background

Artificial intelligence (AI)-assisted colonoscopy systems with contact microscopy capabilities have been reported previously; however, no studies regarding the clinical use of a commercially available system in patients with ulcerative colitis (UC) have been reported. In this study, the diagnostic performance of an AI-assisted ultra-magnifying colonoscopy system for histological healing was compared with that of conventional light non-magnifying endoscopic evaluation in patients with UC.

Methods

The data of 52 patients with UC were retrospectively analyzed. The Mayo endoscopic score (MES) was determined by 3 endoscopists. Using the AI system, healing of the same spot assessed via MES was defined as a predicted Geboes score (GS) < 3.1. The GS was then determined using pathology specimens from the same site.

Results

A total of 191 sites were evaluated, including 159 with a GS < 3.1. The MES diagnosis identified 130 sites as MES0. A total of 120 sites were determined to have healed based on AI. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MES0 for the diagnosis of GS < 3.1 were 79.2%, 90.6%, 97.7%, 46.8%, and 81.2%, respectively. The AI system performed similarly to MES for the diagnosis of GS < 3.1: sensitivity, 74.2%; specificity: 93.8%; PPV: 98.3%; NPV: 42.3%; and accuracy: 77.5%. The AI system also significantly identified a GS of < 3.1 in the setting of MES1 (P = .0169).

Conclusions

The histological diagnostic yield the MES- and AI-assisted diagnoses was comparable. Healing decisions using AI may avoid the need for histological examinations.

Histologic features and predicting prognosis in ulcerative colitis patients with mild endoscopic activity

BACKGROUND/AIMS

We aimed to evaluate the histologic features predictive of prognosis and correlate them with endoscopic findings in patients with ulcerative colitis (UC) having complete or partial mucosal healing (MH).

METHODS

We prospectively collected and reviewed data from patients with UC who underwent colonoscopy or sigmoidoscopy with biopsy. Complete and partial MH were defined as Mayo endoscopic subscores (MESs) of 0 and 1, respectively. Histologic variables, including the Nancy index (NI), predicting disease progression (defined as the need for medication upgrade or hospitalization/surgery), were evaluated and correlated with endoscopic findings.

RESULTS

Overall, 441 biopsy specimens were collected from 194 patients. The average follow-up duration was 14.7 ± 7.4 months. There were 49 (25.3%) and 68 (35.1%) patients with MESs of 0 and 1, respectively. Disease progression occurred only in patients with an MES of 1. NI ≥ 3 was significantly correlated with disease progression during follow-up. Mucosal friability on endoscopy was significantly correlated with NI ≥ 3 (61.1% in NI < 3 vs. 88.0% in NI ≥ 3; p = 0.013).

CONCLUSION

Histological activity can help predict the prognosis of patients with UC with mild endoscopic activity. Mucosal friability observed on endoscopy may reflect a more severe histological status, which can be a risk factor for disease progression.

Histologic assessments in ulcerative colitis: the evidence behind a new endpoint in clinical trials

INTRODUCTION

Treatment goals for ulcerative colitis (UC) are evolving from the achievement of clinical remission to more rigorous goals defined by endoscopic and histologic healing. Achievement of deeper remission targets aims to reduce the risk of colectomy, hospitalizations, and colorectal cancer.

AREAS COVERED

This review covers histologic assessments, histologic remission as a clinical trial endpoint, and the association between histologic disease activity and clinical outcomes. Future directions are also discussed, including the use of advanced imaging and artificial intelligence technologies, as well as potential future treatment targets beyond histologic remission.

EXPERT OPINION

Histologic assessments are used for their sensitivity in measuring mucosal inflammatory changes in UC. Due to correlation with disease activity, histologic assessments may support clinical decision-making regarding treatment decisions as such assessments can be associated with rates of clinical relapse, hospitalization, colectomy, and neoplasia. While histologic remission is limited by varying definitions and multiple histologic indices, work is ongoing to create a consensus on the use of histologic assessments in clinical trials. As research advances, aspirational targets beyond histologic remission, such as molecular healing and disease clearance, are being explored.

Neutrophil-only Histological Assessment of Ulcerative Colitis Correlates with Endoscopic Activity and Predicts Long-term Outcomes in a Multicentre Study

BACKGROUNDS AND AIMS

Absence of neutrophils is the minimum standard to consider histological remission of ulcerative colitis [UC]. The PICaSSO Histological Remission Index [PHRI] is a new simple index for UC, based only on the detection of neutrophils. We evaluate PHRI's correlation with endoscopy and its prognostic value compared with other established indices.

METHODS

Consecutive patients with UC underwent colonoscopy at two referral centres [Birmingham, UK, and Milan, Italy,] and were followed up for 2 years. Correlation between histology (PHRI, Nancy [NHI], and Robarts [RHI] indexes) and endoscopy (Mayo Endoscopic Score [MES], Ulcerative Colitis Endoscopic Index of Severity [UCEIS], and PICaSSO index) was calculated as Spearman coefficients. Diagnostic performance of endoscopy was assessed with receiver operating characteristic [ROC] curves and outcome stratification with Kaplan-Meier curves.

RESULTS

A total of 192 patients with UC was enrolled, representing all grades of endoscopic severity. Correlation between histology and endoscopy did not differ significantly when using PHRI instead of NHI or RHI. In particular, PHRI's correlation with MES, UCEIS, and PICaSSO was 0.745, 0.718, and 0.694, respectively. Endoscopically-assessed remission reflected the absence of neutrophils [PHRI = 0] with areas under the ROC curve of 0.905, 0.906, and 0.877 for MES, UCEIS, and PICaSSO, respectively. The hazard ratio for disease flare between patients in histological activity/remission was statistically similar [p >0.05] across indexes [2.752, 2.706, and 2.871 for RHI, NHI, and PHRI, respectively].

CONCLUSION

PHRI correlates with endoscopy and stratifies risk of relapse similarly to RHI and NHI. Neutrophil-only assessment of UC is a simple yet viable alternative to established histological scores.

Lack of Benefit for Early Escalation to Advanced Therapies in Ulcerative Colitis: Critical Appraisal of Current Evidence

Although ulcerative colitis [UC] shares many common pathways and therapeutic options with Crohn's disease [CD], CD patients are four times more likely to undergo surgery 10 years into their disease in the biological era and are more likely to have extraintestinal manifestations than UC patients. Early treatment in CD has been demonstrated to modify the natural history of the disease and potentially delay surgery. Previous reviews on this topic have borrowed their evidence from CD to make UC-specific recommendations. This review highlights the emergence of UC-specific data from larger cohort studies and a comprehensive individual patient data systemic review and meta-analysis to critically appraise evidence on the utility of early escalation to advanced therapies with respect to short-, medium-, and long-term outcomes. In UC, the utility of the early escalation concept for the purposes of changing the natural history, including reducing colectomy and hospitalizations, is not supported by the available data. Data on targeting clinical, biochemical, endoscopic, and histological outcomes are needed to demonstrate that they are meaningful with regard to achieving reductions in hospitalization and surgery, improving quality of life, and minimizing disability. Analyses of different populations of UC patients, such as those with 'relapsing & remitting' disease or with severe or complicated disease course, are urgently needed. The costs and risk/benefit profile of some of the newer advanced therapies should be carefully considered. In this clinical landscape, it appears premature to advocate an indiscriminate 'one size fits all' approach to escalating to advanced therapies early during the course of UC.

Selected Cytokines and Metalloproteinases in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a collective term for two diseases: ulcerative colitis (UC) and Crohn's disease (CD). There are many factors, e.g., genetic, environmental and immunological, that increase the likelihood of these diseases. Indicators of IBDs include extracellular matrix metalloproteinases (MMPs). The aim of this review is to present data on the role of selected cytokines and metalloproteinases in IBD. In recent years, more and more transcriptomic studies are emerging. These studies are improving the characterization of the cytokine microenvironment inside inflamed tissue. It is observed that the levels of several cytokines are consistently increased in inflamed tissue in IBD, both in UC and CD. This review shows that MMPs play a major role in the pathology of inflammatory processes, cancer, and IBD. IBD-associated inflammation is associated with increased expression of MMPs and reduced ability of tissue inhibitors of metalloproteinases (TIMPs) to inhibit their action. In IBD patients in tissues that are inflamed, MMPs are produced in excess and TIMP activity is not sufficient to block MMPs. This review is based on our personal selection of the literature that was retrieved by a selective search in PubMed using the terms "Inflammatory bowel disease" and "pathogenesis of Inflammatory bowel diseases" that includes systematic reviews, meta-analyses, and clinical trials. The involvement of the immune system in the pathophysiology of IBD is reviewed in terms of the role of the cytokines and metalloproteinases involved.

Automating Ground Truth Annotations for Gland Segmentation Through Immunohistochemistry

Microscopic evaluation of glands in the colon is of utmost importance in the diagnosis of inflammatory bowel disease and cancer. When properly trained, deep learning pipelines can provide a systematic, reproducible, and quantitative assessment of disease-related changes in glandular tissue architecture. The training and testing of deep learning models require large amounts of manual annotations, which are difficult, time-consuming, and expensive to obtain. Here, we propose a method for automated generation of ground truth in digital hematoxylin and eosin (H&E)-stained slides using immunohistochemistry (IHC) labels. The image processing pipeline generates annotations of glands in H&E histopathology images from colon biopsy specimens by transfer of gland masks from KRT8/18, CDX2, or EPCAM IHC. The IHC gland outlines are transferred to coregistered H&E images for training of deep learning models. We compared the performance of the deep learning models to that of manual annotations using an internal held-out set of biopsy specimens as well as 2 public data sets. Our results show that EPCAM IHC provides gland outlines that closely match manual gland annotations (Dice = 0.89) and are resilient to damage by inflammation. In addition, we propose a simple data sampling technique that allows models trained on data from several sources to be adapted to a new data source using just a few newly annotated samples. The best performing models achieved average Dice scores of 0.902 and 0.89 on Gland Segmentation and Colorectal Adenocarcinoma Gland colon cancer public data sets, respectively, when trained with only 10% of annotated cases from either public cohort. Altogether, the performances of our models indicate that automated annotations using cell type-specific IHC markers can safely replace manual annotations. Automated IHC labels from single-institution cohorts can be combined with small numbers of hand-annotated cases from multi-institutional cohorts to train models that generalize well to diverse data sources.

Evaluation of Disease Activity in Inflammatory Bowel Disease: Diagnostic Tools in the Assessment of Histological Healing

Inflammatory bowel disease (IBD) comprises two types of chronic intestinal disorders: Crohn's disease and ulcerative colitis. In long-standing ulcerative colitis disease activity, histological persistent inflammation has been linked to an increased risk of relapse, and long-term corticosteroid use, even when endoscopic remission is reached. In Crohn's disease, the discontinuous nature of lesions and transmural inflammation have limited the standardized histological assessment. The current evidence from research proposes that besides clinical and endoscopic healing, the achievement of histological healing constitutes an endpoint to assess disease activity and remission in IBD patients concerning better long-term disease outcomes. Histological alterations may persist even in the absence of endoscopic lesions. For these reasons, new advanced techniques promise to revolutionize the field of IBD by improving the endoscopic and histologic assessment, disease characterization, and ultimately patient care, with an established role in daily practice for objective assessment of lesions. This review outlines the importance of including microscopic evaluation in IBD, highlighting the clinical benefits of a deep state of disease remission using validated diagnostic methods and scoring systems for daily clinical practice.

An indirect comparison of efficacy including histologic assessment and safety in biologic therapy in ulcerative colitis: Systemic review and network meta-analysis

BACKGROUNDS AND AIMS

There are currently no studies comparing histologic remission of FDA-approved biologics for moderate to severe ulcerative colitis (UC), except for one head-to-head VARSITY trial. The current study employs a network meta-analysis to compare the efficacy, including histologic remission and safety of biologic agents for UC.

METHODS

Using four electronic databases, including Pubmed, EMBASE, The Cochrane Library, and ClinicalTrials.gov, a search was conducted of all literature published until September 2022. Included were studies of randomized controlled trials with adult patients with moderate to severe UC using biologics approved by the FDA. An odd ratio with a 95 percent credible interval and ranking information was calculated for each endpoint.

RESULTS

The results of the network meta-analysis did not reveal statistically significant differences among biological agents. However, the ranking information for each biological agent exhibited the following patterns. Vedolizumab was ranked first for overall efficacy endpoints in the maintenance phase, including histologic remission. Except for histologic remission, Ustekinumab was identified as the top-ranked drug for induction phase efficacy endpoints other than histologic remission. Adalimumab was identified as the top-ranked drug for maintenance phase corticosteroid-free remission. Vedolizumab was identified as the top-ranked drug in the induction phase for Treatment Emergent Adverse Events (TEAE). Adalimumab was identified as the top-ranked drug in the induction phase for infection. For TEAE and infection in the maintenance phase and Treatment Emergent Severe Adverse Events (TESAE) in both the induction and maintenance phases, Ustekinumab was determined to be the top-ranked medication.

CONCLUSIONS

Including histologic remission, for the overall efficacy endpoints in the maintenance phase, VDZ was identified as the first rank drug, but there was no statistically significant difference between biologics. Therefore, the generalization of the results of this study is bounded due to the intrinsic limitations of the study provided.

Histologic Predictors of Clinical Outcomes and Healthcare Utilization in Patients With Ileal Pouch-Anal Anastomosis

BACKGROUND

The prognostic significance of histology in ileal pouch-anal anastomosis (IPAA) remains unclear. The aim of this study was to evaluate if histologic variables are predictive of IPAA clinical outcomes and healthcare utilization.

METHODS

This was a retrospective cohort study of patients with IPAA undergoing surveillance pouchoscopy at a tertiary care institution. Pouch body biopsies were reviewed by gastrointestinal pathologists, who were blinded to clinical outcomes, for histologic features of acute or chronic inflammation. Charts were reviewed for clinical outcomes including development of acute pouchitis, chronic pouchitis, biologic or small molecule initiation, hospitalizations, and surgery. Predictors of outcomes were analyzed using univariable and multivariable logistic and Cox regression.

RESULTS

A total of 167 patients undergoing surveillance pouchoscopy were included. Polymorphonuclear leukocytes (odds ratio [OR], 1.67), ulceration and erosion (OR, 2.44), chronic inflammation (OR, 1.97), and crypt distortion (OR, 1.89) were associated with future biologic or small molecule initiation for chronic pouchitis. Loss of goblet cells was associated with development of chronic pouchitis (OR, 4.65). Pyloric gland metaplasia was associated with hospitalizations (OR, 5.24). No histologic variables were predictive of development of acute pouchitis or surgery. In an exploratory subgroup analysis of new IPAA (<1 year), loss of goblet cells was associated with acute pouchitis (OR, 14.86) and chronic pouchitis (OR, 12.56). Pyloric gland metaplasia was again associated with hospitalizations (OR, 13.99).

CONCLUSIONS

Histologic findings may be predictive of IPAA outcomes. Pathologists should incorporate key histologic variables into pouchoscopy pathology reports. Clinicians may need to more closely monitor IPAA patients with significant histologic findings.

Inflammatory Bowel Disease and Risk of Colorectal Polyps: A Nationwide Population-Based Cohort Study From Sweden

BACKGROUND

Inflammatory bowel disease [IBD] has been linked to an increased risk of colorectal neoplasia. However, the types and risks of specific polyp types in IBD are less clear.

METHODS

We identified 41 880 individuals with IBD (Crohn's disease [CD: n = 12 850]; ulcerative colitis [UC]: n = 29 030]) from Sweden matched with 41 880 reference individuals. Using Cox regression, we calculated adjusted hazard ratios [aHRs] for neoplastic colorectal polyps [tubular, serrated/sessile, advanced and villous] defined by histopathology codes.

RESULTS

During follow-up, 1648 [3.9%] IBD patients and 1143 [2.7%] reference individuals had an incident neoplastic colorectal polyp, corresponding to an incidence rate of 46.1 and 34.2 per 10 000 person-years, respectively. This correlated to an aHR of 1.23 (95% confidence interval [CI] 1.12-1.35) with the highest HRs seen for sessile serrated polyps [8.50, 95% CI 1.10-65.90] and traditional serrated adenomas [1.72, 95% CI 1.02-2.91]. aHRs for colorectal polyps were particularly elevated in those diagnosed with IBD at a young age and at 10 years after diagnosis. Both absolute and relative risks of colorectal polyps were higher in UC than in CD [aHRs 1.31 vs 1.06, respectively], with a 20-year cumulative risk difference of 4.4% in UC and 1.5% in CD, corresponding to one extra polyp in 23 patients with UC and one in 67 CD patients during the first 20 years after IBD diagnosis.

CONCLUSIONS

In this nationwide population-based study, there was an increased risk of neoplastic colorectal polyps in IBD patients. Colonoscopic surveillance in IBD appears important, especially in UC and after 10 years of disease.

Resolving Histological Inflammation in Ulcerative Colitis With Mirikizumab in the LUCENT Induction and Maintenance Trial Programmes

BACKGROUND AND AIMS

To evaluate the effect of mirikizumab, a p19-targeted anti-interleukin-23, on histological and/or endoscopic outcomes in moderately-to-severely active ulcerative colitis [UC].

METHODS

Endoscopic remission [ER], histological improvement [HI], histological remission [HR], histological-endoscopic mucosal improvement [HEMI], and histological-endoscopic mucosal remission [HEMR] were assessed at Week [W]12 [LUCENT-1: N = 1162, induction] and W40 [LUCENT-2: N = 544, maintenance] for patients randomised to mirikizumab or placebo. Analyses were performed to evaluate predictors of: HEMI at W12 with mirikizumab and HEMR at W40 in patients re-randomised to subcutaneous [SC] mirikizumab; associations between W12 histological/endoscopic endpoints and W40 outcomes in mirikizumab responders re-randomised to mirikizumab SC; and associations between W40 endoscopic normalisation [EN] with/without HR.

RESULTS

Significantly more patients treated with mirikizumab achieved HI, HR, ER, HEMI, and HEMR vs placebo [p <0.001], irrespective of prior biologic/tofacitinib failure [p <0.05]. Lower clinical baseline disease activity, female sex, no baseline immunomodulator use, and no prior biologic/tofacitinib failure were predictors of HEMI at W12 [p <0.05]. Corticosteroid use and longer disease duration were negative predictors of achieving HEMR at W40 [p <0.05]. W12 HI, HR, or ER was associated with W40 HEMI or HEMR [p <0.05]; ER at W12 was associated with clinical remission [CR] [p <0.05] and corticosteroid-free remission [CSFR] at W40 [p = 0.052]. HR and HEMR at W12 were associated with CSFR, CR, and symptomatic remission at W40. Alternate HEMR [EN + HR] at W40 was associated with bowel urgency remission at W40 [p <0.05].

CONCLUSIONS

Early resolution of endoscopic and histological inflammation with mirikizumab is associated with better UC outcomes. Clinicaltrials.gov: LUCENT-1, NCT03518086; LUCENT-2, NCT03524092.

Systemic immune-inflammation index as a potential biomarker to monitor ulcerative colitis

OBJECTIVE

The treat-to-target strategy is recommended by Selecting Therapeutic Targets in Inflammatory Bowel Disease II (STRIDE-II) for treating ulcerative colitis (UC), and monitoring remission status is crucial during this management. The systemic immune-inflammation index (SII), defined as platelet * neutrophil/lymphocyte, is a complete blood count-based index reflecting the balance of immune and inflammatory status. This study aims to investigate the feasibility of SII for diagnosing UC and monitoring UC disease activity.

METHODS

This study retrospectively analyzed patients with UC and controls. Relationships between SII and Mayo clinical score, Mayo Endoscopic Score (MES), and Nancy Histological Index (NHI) were evaluated.

RESULTS

167 patients with UC and 106 controls were included. SII significantly increased in patients with UC and was closely correlated with the Mayo clinical score, MES, and NHI. SII diagnosed UC with a cut-off value of 619.1 × 109/L (area under the curve = 0.861, p < 0.0001, sensitivity 79.64%, specificity 77.36%), evaluated clinical remission status with a cut-off value of 1068 × 109/L (area under the curve = 0.691, p < 0.05, sensitivity 55.71%, specificity 81.48%), endoscopic improvement with a cut-off value of 981.3 × 109/L (area under the curve = 0.819, p < 0.0001, sensitivity 65.22%, specificity 89.66%), and histological healing with a cut-off value of 689.3 × 109/L (area under the curve = 0.898, p < 0.0001, sensitivity 88.89%, specificity 95.83%).

CONCLUSION

SII is a potential biomarker for diagnosing UC and monitoring UC disease severity, especially in evaluating mucosal and histological healing during the long-term management in treat-to-target strategy. However, further research is needed to confirm its usefulness and optimize its clinical application.

Correlation of mucosal healing endpoints with long-term clinical and patient-reported outcomes in ulcerative colitis

BACKGROUND

We evaluated the clinical relevance of achieving histologic endoscopic mucosal improvement (HEMI) and the more stringent target of histologic endoscopic mucosal remission (HEMR) in the phase 3 maintenance trial of upadacitinib for moderately to severely active ulcerative colitis.

METHODS

Clinical and patient-reported outcomes were assessed in patients with clinical response after 8- or 16-week upadacitinib induction who received 52-week upadacitinib maintenance treatment. Cross-sectional and predictive analyses evaluated the relationship between HEMR or HEMI at Week 8/16 and Week 52, respectively, and outcomes at Week 52. Adjusted odds ratios (aOR) were derived from logistic regressions for patients achieving HEMR or HEMI without HEMR versus those not achieving HEMI.

RESULTS

Cross-sectional analyses showed that patients with HEMR had greater odds of achieving all clinical and patient-reported outcomes at Week 52 than those not achieving HEMI. In predictive analyses, patients with HEMR at Week 8/16 had significantly greater odds of achieving clinical remission (aOR = 3.6, p = 0.001) and endoscopic remission (aOR = 3.9, p < 0.001) at Week 52 than patients not achieving HEMI and HEMR. For patients achieving HEMI without HEMR, these odds were lower: clinical remission (aOR = 3.2, p < 0.001) and endoscopic remission (aOR = 2.4, p = 0.010). The odds of achieving clinically meaningful improvements in most patient-reported outcomes were directionally similar between HEMI and HEMR, but not statistically different to patients not achieving HEMI. No hospitalizations or surgeries were observed in patients with HEMR at Week 52.

CONCLUSIONS

Achievement of HEMR or HEMI is clinically relevant with HEMR being associated with greater likelihood of improvement in long-term clinical and patient-reported outcomes. https://www.

CLINICALTRIALS

gov NCT02819635.

Difficult-to-treat inflammatory bowel disease: results from an international consensus meeting

Many patients with inflammatory bowel disease (IBD) have persistent symptoms and disease activity despite the best available medical or surgical treatments. These patients are commonly referred to as having difficult-to-treat IBD and need additional therapeutic strategies. However, the absence of standard definitions has impeded clinical research efforts and comparisons of data. Under the guidance of the endpoints cluster of the International Organization for the Study of Inflammatory Bowel Disease, we held a consensus meeting to propose a common operative definition for difficult-to-treat IBD. 16 participants from 12 countries voted on 20 statements covering various elements of difficult-to-treat IBD, such as failure of medical and surgical treatments, disease phenotypes, and specific complaints from patients. "Agreement" was defined as at least 75% consensus. The group agreed that difficult-to-treat IBD is defined by the failure of biologics and advanced small molecules with at least two different mechanisms of action, or postoperative recurrence of Crohn's disease after two surgical resections in adults, or one in children. In addition, chronic antibiotic-refractory pouchitis, complex perianal disease, and comorbid psychosocial complications that impair disease management also qualified as difficult-to-treat IBD. Adoption of these criteria could serve to standardise reporting, guide enrolment in clinical trials, and help identify candidates for enhanced treatment strategies.

Artificial Intelligence in Inflammatory Bowel Disease Endoscopy: Implications for Clinical Trials

Artificial intelligence shows promise for clinical research in inflammatory bowel disease endoscopy. Accurate assessment of endoscopic activity is important in clinical practice and inflammatory bowel disease clinical trials. Emerging artificial intelligence technologies can increase efficiency and accuracy of assessing the baseline endoscopic appearance in patients with inflammatory bowel disease and the impact that therapeutic interventions may have on mucosal healing in both of these contexts. In this review, state-of-the-art endoscopic assessment of mucosal disease activity in inflammatory bowel disease clinical trials is described, covering the potential for artificial intelligence to transform the current paradigm, its limitations, and suggested next steps. Site-based artificial intelligence quality evaluation and inclusion of patients in clinical trials without the need for a central reader is proposed; for following patient progress, a second reading using AI alongside a central reader with expedited reading is proposed. Artificial intelligence will support precision endoscopy in inflammatory bowel disease and is on the threshold of advancing inflammatory bowel disease clinical trial recruitment.

Extraintestinal Manifestations in Induced Colitis: Controversial Effects of N-Acetylcysteine on Colon, Liver, and Kidney

Ulcerative colitis (UC) is a chronic and recurrent inflammatory bowel disease (IBD) characterized by continuous inflammation in the colonic mucosa. Extraintestinal manifestations (EIM) occur due to the disruption of the intestinal barrier and increased permeability caused by redox imbalance, dysbiosis, and inflammation originating from the intestine and contribute to morbidity and mortality. The aim of this study is to investigate the effects of oral N-acetylcysteine (NAC) on colonic, hepatic, and renal tissues in mice with colitis induced by dextran sulfate sodium (DSS). Male Swiss mice received NAC (150 mg/kg/day) in the drinking water for 30 days before and during (DSS 5% v/v; for 7 days) colitis induction. On the 38th day, colon, liver, and kidney were collected and adequately prepared for the analysis of oxidative stress (superoxide dismutase (SOD), catalase (CAT), glutathione reduced (GSH), glutathione oxidized (GSSG), malondialdehyde (MDA), and hydrogen peroxide (H2O2)) and inflammatory biomarkers (myeloperoxidase (MPO) -, tumor necrosis factor alpha - (TNF-α, and interleukin-10 (IL-10)). In colon, NAC protected the histological architecture. However, NAC did not level up SOD, in contrast, it increased MDA and pro-inflammatory effect (increased of TNF-α and decreased of IL-10). In liver, colitis caused both oxidative (MDA, SOD, and GSH) and inflammatory damage (IL-10). NAC was able only to increase GSH and GSH/GSSG ratio. Kidney was not affected by colitis; however, NAC despite increasing CAT, GSH, and GSH/GSSG ratio promoted lipid peroxidation (increased MDA) and pro-inflammatory action (decreased IL-10). Despite some beneficial antioxidant effects of NAC, the negative outcomes concerning irreversible oxidative and inflammatory damage in the colon, liver, and kidney confirm the nonsafety of the prophylactic use of this antioxidant in models of induced colitis, suggesting that additional studies are needed, and its use in humans not yet recommended for the therapeutic routine of this disease.

Next-Generation Endoscopy in Inflammatory Bowel Disease

Endoscopic healing is recognized as a primary treatment goal in Inflammatory Bowel Disease (IBD). However, endoscopic remission may not reflect histological remission, which is crucial to achieving favorable long-term outcomes. The development of new advanced techniques has revolutionized the field of IBD assessment and management. These tools can accurately assess vascular and mucosal features, drawing endoscopy closer to histology. Moreover, they can enhance the detection and characterization of IBD-related dysplasia. Given the persistent challenge of interobserver variability, a more standardized approach to endoscopy is warranted, and the integration of artificial intelligence (AI) holds promise for addressing this limitation. Additionally, although molecular endoscopy is still in its infancy, it is a promising tool to forecast response to therapy. This review provides an overview of advanced endoscopic techniques, including dye-based and dye-less chromoendoscopy, and in vivo histological examinations with probe-based confocal laser endomicroscopy and endocytoscopy. The remarkable contribution of these tools to IBD management, especially when integrated with AI, is discussed. Specific attention is given to their role in improving disease assessment, detection, and characterization of IBD-associated lesions, and predicting disease-related outcomes.

Utility of a rapid assay for prostaglandin E-major urinary metabolite as a biomarker in pediatric ulcerative colitis

Prostaglandin E-major urinary metabolite (PGE-MUM) is a urinary biomarker reflecting ulcerative colitis (UC) activity. This prospective observational study aimed to evaluate the usefulness of PGE-MUM via rapid chemiluminescent enzyme immunoassay in detecting endoscopic remission (ER) and histologic remission (HR) in pediatric UC (6-16 years) in comparison with fecal calprotectin (FCP). ER and HR were defined as Mayo endoscopic score (MES) of 0 and Matts' histological grades (Matts) of 1 or 2, respectively. A total of 104 UC and 39 functional gastrointestinal disorder (FGID) were analyzed. PGE-MUM levels were significantly higher in the UC group than in the FGID group (P < 0.001). FCP levels were significantly elevated in the group without ER and HR than in the group with ER and HR (P < 0.001 and P = 0.001), whereas PGE-MUM levels were significantly higher in the group without ER compared to the group with ER (P < 0.001). No significant differences were noted in the AUCs for PGE-MUM and FCP in detecting ER and HR. Although PGE-MUM was inferior to FCP for the detection of HR, it might have the potential for application as a biomarker of endoscopic activity in pediatric UC owing to its noninvasive and rapid method.

Inflammatory Bowel Diseases: Does One Histological Score Fit All?

Mucosal healing (MH) is the main treatment target in ulcerative colitis (UC) and Crohn's disease, and it is defined by the combination of complete endoscopic and histologic remission. The complete resolution of mucosal inflammation should be confirmed by histology but its assessment is not always univocal. Neutrophil infiltration represents the unique histological marker in discriminating the active vs. quiescent phases of the disease, together with crypt injuries (cryptitis and crypt abscesses), erosions, and ulcerations. On the contrary, basal plasmacytosis is not indicative of activity or the remission of inflammatory bowel diseases (IBDs) but instead represents a diagnostic clue, mostly at the onset. Several histological scoring systems have been developed to assess grade severity, particularly for UC. However, most are complex and/or subjective. The aim of this review was to summarize available scores, their characteristics and limitations, and to present the advantages of a simplified mucosa healing scheme (SHMHS) based on neutrophils and their distribution in the gut mucosa. Finally, we overview future developments including artificial intelligence models for standardization of disease assessments and novel molecular markers of inflammation with potential application in diagnostic practice.

Correlation Between the Nancy Histopathology Index and Markers of Disease Activity in Pediatric Ulcerative Colitis

The Nancy Histological Index (NHI) was developed to assess histological disease activity in adult ulcerative colitis (UC) patients. However, data in pediatrics is limited. Our aim was to determine whether the NHI correlates with different indices of disease activity in pediatric UC patients. We retrospectively reviewed the NHI in rectal biopsies from 61 pediatric UC patients (median age 14.3 years), of whom 34 (55.7%) were newly diagnosed. The median Pediatric Ulcerative Colitis Activity Index (PUCAI) score among participants was 30 (interquartile range 5-55). Most patients exhibited an NHI of 3 (41/61, 67.2%) or 4 (8/61, 13.1%), reflecting moderate-severe histologic inflammation. A moderate positive correlation was identified between the NHI and PUCAI, fecal calprotectin, and Mayo endoscopic scores ( r = 0.60, 0.54, and 0.56 respectively, P ≤ 0.001), but not with CRP or albumin. These results indicate that the NHI has a modest correlation with clinical, laboratory and endoscopic indices of disease activity in pediatric UC patients.

A Current State of Proteomics in Adult and Pediatric Inflammatory Bowel Diseases: A Systematic Search and Review

Inflammatory bowel diseases (IBD) are systemic immune-mediated conditions with predilection for the gastrointestinal tract and include Crohn's disease and ulcerative colitis. Despite the advances in the fields of basic and applied research, the etiopathogenesis remains largely unknown. As a result, only one third of the patients achieve endoscopic remission. A substantial portion of the patients also develop severe clinical complications or neoplasia. The need for novel biomarkers that can enhance diagnostic accuracy, more precisely reflect disease activity, and predict a complicated disease course, thus, remains high. Genomic and transcriptomic studies contributed substantially to our understanding of the immunopathological pathways involved in disease initiation and progression. However, eventual genomic alterations do not necessarily translate into the final clinical picture. Proteomics may represent a missing link between the genome, transcriptome, and phenotypical presentation of the disease. Based on the analysis of a large spectrum of proteins in tissues, it seems to be a promising method for the identification of new biomarkers. This systematic search and review summarize the current state of proteomics in human IBD. It comments on the utility of proteomics in research, describes the basic proteomic techniques, and provides an up-to-date overview of available studies in both adult and pediatric IBD.

HucMSC-Exo Promote Mucosal Healing in Experimental Colitis by Accelerating Intestinal Stem Cells and Epithelium Regeneration via Wnt Signaling Pathway

Background

Mucosal healing has emerged as a crucial therapeutic goal for inflammatory bowel diseases (IBD). Exosomes (Exo) as a potential acellular candidate for stem cell therapy might be competent to promote mucosal healing, while its mechanism remains unexplored.

Methods

Exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs) were subjected to experimental colitis mice intraperitoneally to estimate the role in mucosal healing and the regeneration of intestinal stem cells (ISCs) and epithelium. The intestinal organoid model of IBD was constructed utilizing tumor necrosis factor (TNF)-α for subsequent function analysis in vitro. Transcriptome sequencing was performed to decipher the underlying mechanism and Wnt-C59, an oral Wnt inhibitor, was used to confirm that further. Finally, the potential specific components of hucMSC‑exo were investigated based on several existing miRNA expression datasets.

Results

HucMSC-exo showed striking potential for mucosal healing in colitis mice, characterized by decreased histopathological injuries and neutrophil infiltration as well as improved epithelial integrity. HucMSC-exo up-regulated the expression of leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5), a specific marker for ISCs and accelerated the proliferation of intestinal epithelium. HucMSC-exo endowed intestinal organoids with more excellent capacity to grow and bud under TNF-α stimulation. More than that, the fact that hucMSC-exo activated the canonical Wnt signaling pathway to promote mucosal healing was uncovered by not only RNA-sequencing but also relevant experimental data. Finally, bioinformatics analysis of the existing miRNA expression datasets indicated that several miRNAs abundant in hucMSC-exo involved widely in regeneration or repair related biological processes and Wnt signaling pathway might be one of the most important signal transduction pathways.

Conclusion

Our results suggested that hucMSC-exo could facilitate mucosal healing in experimental colitis by accelerating ISCs and intestinal epithelium regeneration via transferring key miRNAs, which was dependent on the activation of Wnt/β-catenin signaling pathway.

[Inflammatory bowel diseases: Scoring and pathological reports optimization]

The two main forms of inflammatory bowel disease (IBD) are ulcerative colitis (UC) and Crohn's disease (CD). Both diseases have inflammatory flare-ups that alternate with periods of remission. The pathologist may examine biopsies of the digestive tract from IBD patients in different contexts: at the time of the initial diagnosis, in the event of a disease flare-up in order to differentiate a flare of the disease from another cause, particularly an infectious one, and during the long term follow-up of the disease in order to detect the occurrence of dysplastic lesions. Pathologists are increasingly involved in the evaluation of inflammatory activity during the follow-up of IBD patients. The therapeutic management of IBD has evolved significantly and the emergence of new treatments allows a global approach targeting endoscopic mucosal healing. However, mucosal healing is not always correlated with histological healing. Numerous studies have shown the value of histological evaluation during follow-up. A higher score for histological activity in ulcerative colitis predicts a higher likelihood of neoplasia. Histological activity is a better predictor than endoscopic inflammation of the risk. In UC, histological remission may be a long-term therapeutic goal but its role in CD remains unclear. Different scores have been developed to quantify the inflammatory activity of IBD patients and the response to treatment. The aim of this review is to present the main activity scores used in the follow-up of IBD, their interest, their evaluation and their limitations.

Targeted multiomics in childhood-onset SLE reveal distinct biological phenotypes associated with disease activity: results from an explorative study

OBJECTIVE

To combine targeted transcriptomic and proteomic data in an unsupervised hierarchical clustering method to stratify patients with childhood-onset SLE (cSLE) into similar biological phenotypes, and study the immunological cellular landscape that characterises the clusters.

METHODS

Targeted whole blood gene expression and serum cytokines were determined in patients with cSLE, preselected on disease activity state (at diagnosis, Low Lupus Disease Activity State (LLDAS), flare). Unsupervised hierarchical clustering, agnostic to disease characteristics, was used to identify clusters with distinct biological phenotypes. Disease activity was scored by clinical SELENA-SLEDAI (Safety of Estrogens in Systemic Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index). High-dimensional 40-colour flow cytometry was used to identify immune cell subsets.

RESULTS

Three unique clusters were identified, each characterised by a set of differentially expressed genes and cytokines, and by disease activity state: cluster 1 contained primarily patients in LLDAS, cluster 2 contained mainly treatment-naïve patients at diagnosis and cluster 3 contained a mixed group of patients, namely in LLDAS, at diagnosis and disease flare. The biological phenotypes did not reflect previous organ system involvement and over time, patients could move from one cluster to another. Healthy controls clustered together in cluster 1. Specific immune cell subsets, including CD11c+ B cells, conventional dendritic cells, plasmablasts and early effector CD4+ T cells, differed between the clusters.

CONCLUSION

Using a targeted multiomic approach, we clustered patients into distinct biological phenotypes that are related to disease activity state but not to organ system involvement. This supports a new concept where choice of treatment and tapering strategies are not solely based on clinical phenotype but includes measuring novel biological parameters.

Usefulness of texture and color enhancement imaging in assessing mucosal healing in patients with ulcerative colitis

BACKGROUND AND AIMS

Endoscopic remission is known to be defined as a Mayo endoscopic subscore (MES) of ≤1 in patients with ulcerative colitis (UC). However, some individuals experience relapse even after showing endoscopic remission under white-light imaging (WLI), and no tool exists that can detect these individuals. The aim of this study was to clarify the usefulness of texture and color enhancement imaging (TXI) in the assessment of inflammation in patients with UC.

METHODS

This was a prospective, single-arm, observational study conducted at a university hospital. From January 2021 to December 2021, 146 UC patients with endoscopic remission were enrolled. Images were evaluated by WLI, TXI, and pathologic evaluation, followed by prognostic studies. The primary endpoint of the study was the cumulative relapse of UC in each TXI score. The secondary endpoints were the association between TXI and pathologic scores, predictors of relapse, and interobserver agreement between the MES and TXI scores.

RESULTS

Patients with TXI score 2 had significantly lower UC relapse-free rates than did those with TXI scores 0-1 (log-rank test, P < .01). When pathologic remission was defined as Matts grade ≤2, the rate of pathologic remission decreased significantly with higher TXI scores (P = .01). In multivariate analysis, TXI score 2 was the only risk factor for UC relapse (P < .01; hazard ratio, 4.16; 95% confidence interval, 1.72-10.04). Interobserver agreement on the TXI score was good (κ = 0.597-0.823).

CONCLUSION

TXI can be used to identify populations with poor prognosis in MES 1, for whom treatment intensification has been controversial.

Comparative study between histochemical mucus volume, histopathological findings, and endocytoscopic scores in patients with ulcerative colitis

Ulcerative colitis (UC) causes a reduction in goblet cells. However, there have been few reports on the relationship between endoscopic and pathological findings and mucus volume. In this study, we quantitatively evaluated histochemical colonic mucus volume by fixing biopsied tissue sections taken from patients with UC in Carnoy's solution and compared it with endoscopic and pathological findings to determine whether there is a correlation between them. Observational study. A single-center, university hospital in Japan. Twenty-seven patients with UC (male/female, 16/11; mean age, 48.4 years; disease median duration, 9 years) were included in the study. The colonic mucosa of the most inflamed area and the surrounding less inflamed area were evaluated separately by local MES and endocytoscopic (EC) classification. Two biopsies were taken from each area; one was fixed with formalin for histopathological evaluation, and the other was fixed with Carnoy's solution for the quantitative evaluation of mucus via histochemical Periodic Acid Schiff and Alcian Blue staining. The relative mucus volume was significantly reduced in the local MES 1-3 groups, with worsening findings in EC-A/B/C and in groups with severe mucosal inflammation, crypt abscess, and severe reduction in goblet cells. The severity of inflammatory findings in UC by EC classification correlated with the relative mucus volume suggesting functional mucosal healing. We found a correlation between the colonic mucus volume and endoscopic and histopathological findings in patients with UC, and a stepwise correlation with disease severity, particularly in EC classification.

Mise au point de l’utilisation de l’intelligence artificielle dans la prise en charge des maladies inflammatoires chroniques de l’intestin

Complexity of inflammatory bowel diseases (IBD) lies on their management and their biology. Clinics, blood and fecal samples tests, endoscopy and histology are the main tools guiding IBD treatment, but they generate a large amount of data, difficult to analyze by clinicians. Because of its capacity to analyze large number of data, artificial intelligence is currently generating enthusiasm in medicine, and this technology could be used to improve IBD management. In this review, after a short summary on IBD management and artificial intelligence, we will report pragmatic examples of artificial intelligence utilisation in IBD. Lastly, we will discuss the limitations of this technology.

Low Fecal Calprotectin Predicts Histological Healing in Patients with Ulcerative Colitis with Endoscopic Remission and Leads to Prolonged Clinical Remission

BACKGROUND

Consensus regarding the cutoff value of fecal calprotectin (FC) for predicting histological healing (HH) in ulcerative colitis (UC) is lacking. This study aimed to determine an optimal FC cutoff value for predicting HH in patients with UC with clinical and endoscopic remission. Furthermore, FC's predictability for prolonged clinical remission (CR) was investigated.

METHODS

Patients with UC in clinical and endoscopic remission, defined as a partial Mayo score (PMS) ≤ 2 points and a Mayo endoscopic subscore 0-1, were prospectively enrolled. Biopsy samples were evaluated by Geboes score (GS), with HH defined as a GS < 2.0. Patients were followed for 2 years or until relapse, defined as a PMS > 2 or medication escalation.

RESULTS

Seventy-six patients with UC were included. The median FC value in patients with HH (n = 40) was 56.2 µg/g, significantly lower than that in those with histological activity (118.1 µg/g; P < .01). The area under the curve (AUC) in a receiver operating characteristic (ROC) curve analysis to predict HH for FC was 0.71 (95% confidence interval [CI], 0.59-0.83), with an optimal cutoff value of 82.7 µg/g (73% sensitivity; 64% specificity; P < .01). Of 74 patients observed for 2 years, 54 (73%) had prolonged CR. In the ROC curve analysis, the AUC to predict prolonged CR for FC was 0.79 (95% CI, 0.68-0.90), equivalent to that for HH (0.73; 95% CI, 0.64-0.86; P = .40). The optimal FC cutoff value to predict prolonged CR was 84.6 µg/g (72% sensitivity; 85% specificity; P < .01).

CONCLUSIONS

Fecal calprotectin < 82 µg/g predicts HH in patients with UC with clinical and endoscopic remission. Low FC leads to prolonged CR, equivalent to HH.

Histologic Activity and Steroid Use History Are Risk Factors of Clinical Relapse in Ulcerative Colitis With Mayo Endoscopic Subscore of 0 or 1

BACKGROUND

The treatment goal of ulcerative colitis (UC) has changed from the control of symptoms to mucosal healing, previously evaluated mainly by endoscopy. Recently, the importance of histologic activity has emerged. Therefore, this study aimed to investigate the risk of clinical relapse according to histologic activity in UC with a Mayo endoscopic subsccore (MES) of 0 or 1.

METHODS

In a retrospective cohort after our center's biopsy guideline for UC was instituted, 492 UC patients with an MES of 0 or 1 were enrolled and analyzed. The primary outcome was the development of a clinical relapse including changes in medication, hospitalization, colectomy, and the development of colorectal cancer during the follow-up period.

RESULTS

During the median 549 days of follow-up, 92 (18.7%) patients had a clinical relapse. All the patients changed their medication, including 4 hospitalized patients. Histologic activity defined by a Geboes score of ≧3.1 (hazard ratio [HR], 1.732; P = .035) and steroid use history (HR, 1.762; P = .008) were independent factors associated with clinical relapse. When stratified, the 1- and 2-year incidence rates of clinical relapse were 4.1% and 10.6%, respectively, for patients with histologic improvement and no steroid use history, whereas the rates were 23.9% and 39.4% for patients with histologic activity and steroid use history.

CONCLUSIONS

In UC with an MES of 0 or 1, histologic activity and steroid use history can be used to stratify the risk of clinical relapse.