Disease activity and mucosal healing in inflammatory bowel disease: a new role for histopathology? Virchows Arch. 2018;472:99-110. [PMID: 28555281 DOI: 10.1007/s00428-017-2156-5]

Effects of Mirikizumab on Histologic Resolution of Crohn's Disease in a Randomized Controlled Phase 2 Trial

BACKGROUND & AIMS

Histologic evaluation of mucosal healing in Crohn's disease is an evolving treatment target. We evaluated histologic outcomes for mirikizumab efficacy and associations with endoscopic and 1-year outcomes.

METHODS

Biopsy specimens from 1 ileal and 4 colonic segments were evaluated at weeks 0, 12, and 52 from each of the 170 SERENITY participants. Criteria for the weeks 12 and 52 histologic response were no epithelial neutrophils or epithelial damage, or >50% decrease in either the Robarts Histopathology Index or the active Global Histologic Disease Activity Score, and remission (no mucosal neutrophils and no epithelial damage) had to be met in all biopsy specimens. Agreement was evaluated between histologic and endoscopic end points. Associations between 1-year outcomes and week 12 histologic and endoscopic response were evaluated.

RESULTS

At week 12, 1000 mg mirikizumab resulted in greater rates of histologic response (66% vs 27%; P < .001) and remission (26% vs 6%; P < .01) than placebo. Rates were numerically similar at 1 year (mirikizumab pooled response, 46%-69%; remission, 13%-31%). Agreement between week 12 histologic and endoscopic response was 69% (Cohen's kappa coefficient [κ] = 0.40) and remission was 83% (κ = 0.38) in all pooled arms, including placebo. At 1 year, the percentage of participants who received any dose of mirikizumab and achieved endoscopic remission differed by their week 12 response: histologic (20%), endoscopic (25%), combined histology-endoscopy (45%), or neither (4%) (P = .003).

CONCLUSIONS

In a post hoc analysis of phase 2 data, mirikizumab induced and sustained histologic response and remission in Crohn's disease over 52 weeks. Early combined histologic-endoscopic response was associated with endoscopic remission after 1 year of treatment with mirikizumab (ClinicalTrials.gov NCT02891226).

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.

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.

Is histological healing more clinically valuable than endoscopic healing in Crohn's disease?

OBJECTIVES

Small bowel (SB) endoscopic healing has not been well explored in patients with Crohn's disease (CD). This study aimed to assess the clinical utility of SB endoscopic mucosal and histological healing in patients with CD.

METHODS

In total, 99 patients with CD in clinical-serological remission were retrospectively followed after they underwent colonoscopy and double-balloon enteroscopy. Time until clinical relapse (CD activity index of >150 with an increase of >70 points) and serological relapse (abnormal elevation of C-reactive protein levels) constituted the primary endpoints.

RESULTS

Of the 99 patients, 75 (74.7%) exhibited colonoscopic healing and 43 (43.4%) exhibited SB endoscopic healing. Clinical relapse, serological relapse, hospitalization, and surgery occurred in 8 (18.6%), 11 (25.6%), 11 (25.6%), and 2 (4.6%) patients, respectively. Of the 43 patients who exhibited SB endoscopic healing, 21 (48.8%) achieved histological healing. Clinical relapse, serological relapse, hospitalization, and surgery occurred in 4 (19.0%), 7 (33.3%), 7 (33.3%), and 1 (4.8%) patient, respectively. There was no statistically significant difference in the number of patients who relapsed, were hospitalized, or underwent surgery between those who exhibited histological healing and those who did not.

CONCLUSION

A substantial number of patients who were in clinical-serological remission did not undergo SB endoscopic healing, and the lesions increased their risk of clinical relapse. Thus, endoscopic healing may be of greater clinical value than histological healing when evaluating the remission of patients with CD.

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.

ASSESSMENT OF RISK FACTORS FOR SURGERY TREATMENT OF CROHN'S DISEASE: A HOSPITAL COHORT

BACKGROUND

New therapies have revolutionized the treatment of Crohn's disease (CD), but in some countries, the surgery rate has not changed, the frequency of emergency surgery is underestimated, and surgical risk is poorly studied.

AIMS

The aim of this study was to identify risk factors and clinical indications for primary surgery in CD patients at the tertiary hospital.

METHODS

This was a retrospective cohort of a prospectively collected database of 107 patients with CD from 2015 to 2021. The main outcomes were the incidence of surgery treatment, types of procedures performed, surgical recurrence, surgery free time, and risk factors for surgery.

RESULTS

Surgical intervention was performed in 54.2% of the patients, and most of the procedures were emergency surgeries (68.9%). The elective procedures (31.1%) were performed over 11 years after diagnosis. The main indications for surgery were ileal stricture (34.5%) and anorectal fistulas (20.7%). The most frequent procedure was enterectomy (24.1%). Recurrence surgery was most common in emergency procedures (OR 2.1; 95%CI 1.6-6.6). Montreal phenotype L1 stricture behavior (RR 1.3; 95%CI 1.0-1.8, p=0.04) and perianal disease (RR 1.43; 95%CI 1.2-1.7) increased the risk of emergency surgeries. The multiple linear regression showed age at diagnosis as a risk factor for surgery (p=0.004). The study of surgery free time showed no difference in the Kaplan-Meier curve for Montreal classification (p=0.73).

CONCLUSIONS

The risk factors for operative intervention were strictures in ileal and jejunal diseases, age at diagnosis, perianal disease, and emergency indications.

ECCO Position on Harmonisation of Crohn's Disease Mucosal Histopathology

In inflammatory bowel disease [IBD], mucosal healing is a major therapeutic target and a reliable predictor of clinical course. However, endoscopic mucosal healing is not synonymous with histological healing, and the additional benefits of including histological remission as a target are unclear. In Crohn´s disease [CD], there are few studies highlighting the value of histological remission as a therapeutic target. Histological activity can persist in CD patients who are in endoscopic remission, and the absence of histological activity may be associated with lower relapse rates. Therefore, standardisation of procedures to evaluate CD histological activity is desirable. Topics that would benefit from standardisation and harmonisation include biopsy procedures, biopsy processing techniques, the content of histological scores, and the definitions of histological remission, histological response, and histological activity. In line with these needs, the European Crohn's and Colitis Organisation [ECCO] assembled a consensus group with the objective of developing position statements on CD histology based on published evidence and expert consensus. There was agreement that definitions of histological remission should include absence of erosion, ulceration, and mucosal neutrophils; that the absence of neutrophilic inflammation is an appropriate histological target in CD; that CD histological scores, such as the Global Histological Disease Activity Score, lack formal validation; and that histological scoring systems for ulcerative colitis, including the Geboes Score, Robarts Histopathology Index, and Nancy Histological Index, can be used for scoring intestinal biopsies in CD patients.

Simplified Histologic Mucosal Healing Scheme (SHMHS) for inflammatory bowel disease: a nationwide multicenter study of performance and applicability

BACKGROUND

Assessment of mucosal healing is important for the management of patients with inflammatory bowel disease (IBD), but endoscopy can miss microscopic disease areas that may relapse. Histological assessment is informative, but no single scoring system is widely adopted. We previously proposed an eight-item histological scheme for the easy, fast reporting of disease activity in the intestine. The aim of the present study was to evaluate the performance of our Simplified Histologic Mucosal Healing Scheme (SHMHS).

METHODS

Between April and May 2021 pathologists and gastroenterologists in Italy were invited to contribute to this multicenter study by providing data on single endoscopic-histological examinations for their IBD patients undergoing treatment. Disease activity was expressed using SHMHS (maximum score, 8) and either Simple Endoscopic Score for Crohn's Disease (categorized into grades 0-3) or Mayo Endoscopic Subscore (range 0-3).

RESULTS

Thirty hospitals provided data on 597 patients (291 Crohn's disease; 306 ulcerative colitis). The mean SHMHS score was 2.96 (SD = 2.42) and 66.8% of cases had active disease (score ≥ 2). The mean endoscopic score was 1.23 (SD = 1.05), with 67.8% having active disease (score ≥ 1). Histologic and endoscopic scores correlated (Spearman's ρ = 0.76), and scores for individual SHMHS items associated directly with endoscopic scores (chi-square p < 0.001, all comparisons). Between IBD types, scores for SHMHS items reflected differences in presentation, with cryptitis more common and erosions/ulcerations less common in Crohn's disease, and the distal colon more affected in ulcerative colitis.

CONCLUSIONS

SHMHS captures the main histological features of IBD. Routine adoption may simplify pathologist workload while ensuring accurate reporting for clinical decision making.

Measuring Histologic Activity in Inflammatory Bowel Disease: Why and How

Histology is used to confirm the diagnosis of inflammatory bowel disease, exclude superimposed infections, and to evaluate for dysplasia. Histology has rarely been used to measure disease activity and guide therapy despite evidence that histologic measurements have value in predicting important clinical outcomes. More recently, there have been numerous studies supporting a role for histologic disease activity measurements in predicting a variety of outcomes including relapse, hospitalizations, steroid use, and dysplasia. The histologic assessment was superior to endoscopic measurements in many of these studies. This review will summarize the recent literature regarding histologic disease activity measurements in ulcerative colitis and Crohn disease. A detailed description of histologic scoring systems will also be provided to provide pathologists with the necessary tools to accurately measure disease activity.

Peptidomic and proteomic analysis of stool for diagnosing IBD and deciphering disease pathogenesis

Background The sensitivities and specificities of C-reactive protein (CRP) and faecal calprotectin (fCal), as recommended for inflammatory bowel diseases (IBD) diagnosis and monitoring, are low. Our aim was to discover new stool protein/peptide biomarkers for diagnosing IBD. Methods For peptides, MALDI-TOF/MS (m/z 1000-4000) was performed using stools from an exploratory (34 controls; 72 Crohn's disease [CD], 56 ulcerative colitis [UC]) and a validation (28 controls, 27 CD, 15 UC) cohort. For proteins, LTQ-Orbitrap XL MS analysis (6 controls, 5 CD, 5 UC) was performed. Results MALDI-TOF/MS spectra of IBD patients had numerous features, unlike controls. Overall, 426 features (67 control-associated, 359 IBD-associated) were identified. Spectra were classified as control or IBD (absence or presence of IBD-associated features). In the exploratory cohort, the sensitivity and specificity of this classification algorithm were 81% and 97%, respectively. Blind analysis of the validation cohort confirmed 97% specificity, with a lower sensitivity (55%) paralleling active disease frequency. Following binary logistic regression analysis, IBD was independently correlated with MALDI-TOF/MS spectra (p < 0.0001), outperforming fCal measurements (p = 0.029). The IBD-correlated m/z 1810.8 feature was a fragment of APC2, homologous with APC, over-expressed by infiltrating cells lining the surface in UC or the muscularis-mucosae in CD (assessed by immunohistochemistry). IBD-associated over-expressed proteins included immunoglobulins and neutrophil proteins, while those under-expressed comprised proteins of the nucleic acid assembly or those (OLFM4, ENPP7) related to cancer risk. Conclusions Our study provides evidence for the clinical utility of a novel proteomic method for diagnosing IBD and insight on the pathogenic role of APC. Moreover, the newly described IBD-associated proteins might become tools for cancer risk assessment in IBD patients.

Is histological healing a feasible endpoint in ulcerative colitis?

INTRODUCTION

Currently, treatment goals in ulcerative colitis aim to achieve clinical remission and endoscopic mucosal healing. Emerging evidence suggests that histologic assessment of inflammation is a sensitive marker that can outcompete mucosal healing in predicting the clinical course of disease in patients with ulcerative colitis. Based on this, histologic healing is frequently included as a secondary endpoint in pharmacological trials.

AREAS COVERED

We introduce currently used clinical and endoscopic treatment goals, summarize commonly used histologic scoring systems and then provide an overview on the relevance of histologic healing on the outcome in patients with ulcerative colitis. Finally, we review the efficacy of existing UC therapies for inducing histologic remission.

EXPERT OPINION

Histologic healing is achievable in a substantial portion of UC patients. Further, histologic healing is, as consolidated by several meta-analyses, associated with better disease outcome compared to clinical remission and/or endoscopic healing. However, before becoming a widely acceptable treatment endpoint, consensus definitions for histologic healing and the technical aspects as well as for the timing for obtaining biopsies are needed. And finally, we need more evidence to show that resolution of microscopic inflammation as a means of therapy change or dose escalation is indeed a superior endpoint.

Ileal or Colonic Histologic Activity Is Not Associated With Clinical Relapse in Patients With Crohn's Disease in Endoscopic Remission

BACKGROUND & AIMS

Goals of treatment for Crohn's disease (CD) are clinical and endoscopic remission. It is not clear whether histologic markers of healing associate with endoscopic remission in patients with CD.

METHODS

We identified patients with CD from a single institutional registry, and collected data from 129 patients (46.5% female; mean age 25 y; mean CD duration 14.5 y) who underwent colonoscopy evaluation and had simple endoscopic scores for CD below 3 (the definition of endoscopic remission). Histologic signs of CD activity were graded in 192 biopsies (90 ileum and 102 colon), and disease was classified as active (presence of crypt destruction, neutrophils, erosions or ulcerations), quiescent (presence of architectural distortion and chronic inflammatory infiltrate), or normal histology (none of these). The primary outcome was clinical relapse within 2 y (dose escalation, change in therapy, need for systemic steroids, or CD-related hospitalization or surgery). We performed multivariable regression adjusting for relevant confounders to examine the independent predictive value of histologic activity.

RESULTS

Within 2 y of endoscopic evaluation, 42 patients (32.6%) had a clinical relapse. There were no significant differences in proportions of patients with active ileal CD (23.8%), quiescent CD (28.6%), or normal histology (37%) between those who relapsed and those remaining in remission (P = .43). There were no significant differences in proportions of relapses among patients with active colonic disease (38.1%), quiescent disease (35.0%), or normal histology (27.9%, P = .73). A linear regression analysis found no association between histologic features of active disease in ileal histology biopsies and symptom scores (Harvey Bradshaw index and simple inflammatory bowel disease questionnaire scores).

CONCLUSIONS

In an analysis of biopsies from patients with CD who had achieved clinical and endoscopic remission, histologic remission was not associated with clinical relapse within 2 years.

Normal gastrointestinal tract inflammatory cells and review of select benign hematolymphoid proliferations

The luminal gastrointestinal tract can be a site of robust immune response in which reactive lymphoproliferative processes can sometimes be difficult to distinguish from lymphoma. In this article, we review gastrointestinal tract normal resident inflammatory cells and common nonneoplastic lymphoproliferative responses with emphasis on their differential and links to lymphoma. Topics that are covered include lymphocytic esophagitis, gastric chronic inflammation, mucosa-associated lymphoid tissue, and ulceration, small intestinal lymphoid hyperplasia, celiac disease, microscopic colitis, inflammatory bowel disease, primary immunodeficiency, graft-versus-host disease, and anti-programmed cell death protein-1 effect. We additionally present the less common differential of histiocytic processes within the gastrointestinal tract. The aim of this paper is to serve as a reference for practicing pathologists facing lymphoid, lymphoplasmacytic, or histiocytic processes in the luminal gastrointestinal tract. We hope to help the practicing pathologist distinguish benign from malignant entities and identify features requiring further workup.

Down-Regulation of Colonic ACE2 Expression in Patients With Inflammatory Bowel Disease Responding to Anti-TNF Therapy: Implications for COVID-19

Background and Aims: Angiotensin-converting enzyme II (ACE2) is the key molecule for understanding the pathophysiology of COVID-19. The risk of COVID-19 and impact of immunosuppressive treatment on disease course in patients with inflammatory bowel disease (IBD) remain controversial. We aimed to determine the change of intestinal ACE2 expression before and after biologics treatment including anti-tumor necrosis factor α (anti-TNFα), anti-integrin, and anti-interleukin (IL)12/23 in IBD patients. Methods: We analyzed the ACE2 expression through the public database of paired intestinal biopsies from IBD patients before and after biologic therapy. Change of ACE2 RNA and protein expression were validated in two independent cohorts (Birmingham cohort and Guangzhou cohort). The correlation between ACE2 expression and disease activity was also analyzed. Results: Mining information from the GEO database showed that compared with healthy control, intestinal ACE2 expression was downregulated in ileum of CD patients, while upregulated in colon of both CD and UC patients. Colonic ACE2 RNA expression was decreased significantly in patients responding to anti-TNFα but not anti-integrin and anti-IL12/23, which was validated in the Birmingham cohort. Using the Guangzhou cohort including 53 patients matched by pre- and post-anti-TNFα therapy, colonic ACE2 protein expression was significantly downregulated after anti-TNFα treatment in responders (P < 0.001) rather than non-responders. Colonic ACE2 expression was significantly higher in patients with severe histologically active disease compared with those with moderate (P < 0.0001) and mild (P = 0.0002) histologically active disease. Conclusion: Intestinal inflammation influences the expression of intestinal ACE2 in IBD patients, with different alterations in the ileum and colon. Colonic ACE2 expression was downregulated after anti-TNFα therapy in IBD patients responding to treatment. This might provide new clues regarding the risk of SARS-CoV-2 infection and the potential benefit of sustaining anti-TNFα treatment in patients with IBD.

A Novel Pharmacological Approach to Enhance the Integrity and Accelerate Restitution of the Intestinal Epithelial Barrier

BACKGROUND

Disruption of the gut barrier is an essential mechanism of inflammatory bowel diseases (IBDs) contributing to the development of mucosal inflammation. A hallmark of barrier disruption is the disassembly of epithelial adherens junctions (AJs) driven by decreased expression of a major AJ protein, E-cadherin. A group of isoxazole compounds, such as E-cadherin-upregulator (ECU) and ML327, were previously shown to stimulate E-cadherin expression in poorly differentiated human cancer cells. This study was designed to examine whether these isoxazole compounds can enhance and protect model intestinal epithelial barriers in vitro.

METHODS

The study was conducted using T84, SK-CO15, and HT-29 human colonic epithelial cell monolayers. Disruption of the epithelial barrier was induced by pro-inflammatory cytokines, tumor necrosis factor-α, and interferon-γ. Barrier integrity and epithelial junction assembly was examined using different permeability assays, immunofluorescence labeling, and confocal microscopy. Epithelial restitution was analyzed using a scratch wound healing assay.

RESULTS

E-cadherin-upregulator and ML327 treatment of intestinal epithelial cell monolayers resulted in several barrier-protective effects, including reduced steady-state epithelial permeability, inhibition of cytokine-induced barrier disruption and junction disassembly, and acceleration of epithelial wound healing. Surprisingly, these effects were not due to upregulation of E-cadherin expression but were mediated by multiple mechanisms including inhibition of junction protein endocytosis, attenuation of cytokine-induced apoptosis, and activation of promigratory Src and AKT signaling.

CONCLUSIONS

Our data highlight ECU and ML327 as promising compounds for developing new therapeutic strategies to protect the integrity and accelerate the restitution of the intestinal epithelial barrier in IBD and other inflammatory disorders.

Anti-tumor Necrosis Factor-alpha Exposure Impacts Vedolizumab Mucosal Healing Rates in Pediatric Inflammatory Bowel Disease

BACKGROUND

Vedolizumab (VDZ) is effective for treating both adult and pediatric onset inflammatory bowel disease (IBD). Clinical outcomes, however, have been reported to be superior in patients naïve to anti-tumor necrosis factor (TNF). With the growing interest in endoscopic endpoints, we aimed to describe rates of mucosal healing in pediatric patients being treated with VDZ and examine the influence of anti-TNF on outcomes.

METHODS

We conducted a retrospective review of all IBD patients ≤21 years of age who initiated VDZ and underwent endoscopy. Primary outcome was mucosal healing (composite of endoscopic [SES-CD] and Mayo score UC) and histological remission [Nancy index-UC and Crohn disease (CD) histologic activity]. Descriptive statistics summarized the data. Comparisons were made for endpoints based on anti-TNF exposure using univariate testing.

RESULTS

Sixty-eight patients were included in the final analysis; 35 with UC and 33 with CD. Thirty-two patients (22 UC and 10 CD) were anti-TNF-naïve and 36 patients (13 UC and 23 CD) were anti-TNF-exposed. The median duration on VDZ before endoscopic assessment was 49 (IQR 32-73) weeks. A total of 38% (25/66) of patients met the primary outcome of mucosal healing and did not differ between anti-TNF-naïve or anti-TNF-exposed. Endoscopic remission was achieved by 51% with significantly more anti-TNF naïve patients reaching this endpoint (66% vs 40%, P = 0.03). Histologic remission was achieved by 42% of patients with a nonsignificant trend towards improved histologic remission rates in anti-TNF-naïve patients (52% vs 33%, P = 0.13).

CONCLUSIONS

VDZ is associated with mucosal healing in pediatric IBD. Anti-TNF exposure significantly impacted endoscopic remission, but not histologic remission in children on VDZ.

Consumption of a baked corn and bean snack reduced chronic colitis inflammation in CD-1 mice via downregulation of IL-1 receptor, TLR, and TNF-α associated pathways

Ulcerative colitis (UC) is a condition that has been rising in the number of cases around the world. Food products made from natural ingredients such as corn and common bean might serve as alternatives for the treatment of UC. This study aimed to assess the anti-inflammatory effect of the consumption of a baked corn and bean snack (CBS) in an in vivo model of UC using 2% dextran sodium sulfate (DSS) as inductor of colitis. CD-1 mice (45, n = 9/group) were randomly separated into 5 groups, treated for 6-weeks as follows: G1 (basal diet, BD), G2 (2% DSS), G3 (20 g CBS/body weight BW/day + BD), G4 (40 g CBS/BW/day + BD) and G5 (60 g CBS/BW/day + BD). BW, Disease Activity Index (DAI), and feces were collected throughout the treatment. After euthanasia, organs (spleen, liver, and colon) were excised and weighed. Feces were analyzed for β-glucuronidase (β-GLUC) activity and gas-chromatography. The colons were analyzed for histopathology, myeloperoxidase (MPO) activity, and gene analysis. At the end of treatments, among the DSS-induced groups, G3 exhibited the lowest BW losses (11.5%), MPO activity (10.4%) and β-GLUC (8.6%). G4 presented the lowest DAI (0.88), relative spleen weight, and histological inflammation score (p < 0.05). Compared to G2, CBS consumption significantly (p < 0.05) reduced serum TNF-α, IL-10, and MCP-1 levels. The fecal metabolome analysis ranked 9-decenoic acid, decane, and butyric acid as the main contributors of pathways associated with the β-oxidation of fatty acids. G4 showed the highest fecal/cecal contents of short-chain fatty acids among all the DSS-induced groups. For the gene expression, G4 was clustered with G1, showing a differential inhibition of the pro-inflammatory genes Il1r1, Il1a, Tlr4, Tlr2, and Tnfrsf1b. In conclusion, CBS consumption decreased the inflammatory state and reduced the expression of the IL-1 receptor, TLR, and TNF-α-associated pathways in DSS-induced UC in CD-1 mice.

Development of a prognostic model for one-year surgery risk in Crohn’s disease patients: A retrospective study

BACKGROUND

Accelerated therapeutic treatment should be considered in patients with progressive Crohn’s disease (CD) to prevent complications as well as surgery. Therefore, screening for risk factors and predicting the need for early surgery are of great importance in clinical practice.

AIM

To establish a model to predict CD-related early surgery.

METHODS

This was a retrospective study collecting data from CD patients diagnosed at our inflammatory bowel disease center from January 1, 2012 to December 31, 2016. All data were randomly stratified into a training set and a testing set at a ratio of 8:2. Multivariable logistic regression analysis was conducted with receiver operating characteristic curves constructed and areas under the curve calculated. This model was further validated with calibration and discrimination estimated. A nomogram was finally developed.

RESULTS

A total of 1002 eligible patients were enrolled with a mean follow-up period of 53.54 ± 13.10 mo. In total, 24.25% of patients received intestinal surgery within 1 year after diagnosis due to complications or disease relapse. Disease behavior (B2: OR [odds ratio] = 6.693, P < 0.001; B3: OR = 14.405, P < 0.001), smoking (OR = 4.135, P < 0.001), body mass index (OR = 0.873, P < 0.001) and C-reactive protein (OR = 1.022, P = 0.001) at diagnosis, previous perianal (OR = 9.483, P < 0.001) or intestinal surgery (OR = 8.887, P < 0.001), maximum bowel wall thickness (OR = 1.965, P < 0.001), use of biologics (OR = 0.264, P < 0.001), and exclusive enteral nutrition (OR = 0.089, P < 0.001) were identified as independent significant factors associated with early intestinal surgery. A prognostic model was established and further validated. The receiver operating characteristic curves and calculated areas under the curves (94.7%) confirmed an ideal predictive ability of this model with a sensitivity of 75.92% and specificity of 95.81%. A nomogram was developed to simplify the use of the predictive model in clinical practice.

CONCLUSION

This prognostic model can effectively predict 1-year risk of CD-related intestinal surgery, which will assist in screening progressive CD patients and tailoring therapeutic management.

Histological healing: should it be considered as a new outcome for ulcerative colitis?

Introduction: Currently, mucosal healing is considered as a composite treatment end-point in inflammatory bowel disease (IBD) since it has been demonstrated to improve disease-related outcomes. The definition of mucosal healing has evolved and current evidence suggests that in addition to endoscopic healing the achievement of histological remission (HR) represents a potential novel target in the management of IBD in relation to better long-term disease outcomes.Areas covered: We aimed to review the current literature on HR in ulcerative colitis and discuss its limitations and advantages when adopting this potential new target as an ultimate treatment outcome in clinical trials and routine clinical practice.Expert opinion: HR is achievable in UC with different rates in conventional therapies, biological and novel drugs. Targeting HR in UC lowers the risk of hospitalizations, colectomy, and colorectal cancer. HR occurs later than endoscopic remission, longer treatment courses are associated with higher HR assessment. This might imply modifying monitoring time schedules and algorithms. Prospective data are needed to support histological healing as a new treatment target in UC.

Fecal Eosinophil Cationic Protein Is a Diagnostic and Predictive Biomarker in Young Adults with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Fecal biomarkers are important non-invasive markers monitoring disease activity in inflammatory bowel disease (IBD). We compared the significance of fecal eosinophil cationic protein (fECP) and fecal calprotectin (fCal).

METHODS

fECP and fCal were measured in patients with Crohn's disease (CD, n = 97), ulcerative colitis (UC, n = 53), Clostridioides difficile infection (CDI, n = 9), primary food allergy (PFA, n = 11), pollen-associated food allergy (n = 25) and non-inflammatory controls (n = 78). Results were correlated with clinical and endoscopic IBD activity scores.

RESULTS

fECP was significantly elevated in CD, UC, CDI and PFA compared to controls. fCal was significantly increased in CD, UC and CDI. fECP had lower diagnostic accuracy than fCal (area under the curve (AUC) = 0.88) in differentiating between endoscopically active and inactive patients with IBD (AUC = 0.77, ROC analysis). In contrast to fCal, fECP correlated negatively with age and levels were also elevated in clinically and endoscopically inactive patients with IBD <45 years (endoscopically inactive IBD vs controls; AUC for fECP = 0.86; AUC for fCal = 0.62). However, in those patients with low inflammatory activity (fCal <250 mg/kg), high fECP indicated the need for treatment modification or surgery (fECP <200 µg/kg = 22%; 200-600 µg/kg = 44%; >600 µg/kg = 82%) at month 48 of follow-up.

CONCLUSIONS

fECP is a diagnostic and prognostic marker in young patients with IBD in remission.

The Role of Histology in Determining Disease Activity, Treatment, and Prognosis: Are We There yet?

Histologic activity in inflammatory bowel disease is associated with an increased risk of clinical relapse, surgery, hospitalizations, and disease-associated dysplasia independent of clinical or endoscopic activity. Several histologic scoring systems exist to capture disease activity. However, none has been validated to assess prognosis or response to therapy and there is no universally accepted definition of histologic healing or remission. Although histologic healing is not a current recommended target for treatment, it may be a more sensitive marker of disease activity. Future studies are needed to determine standardized definitions of disease activity, healing, and evaluating normalization of histology as clinical trial outcomes.

Histologic Healing Rates of Medical Therapies for Ulcerative Colitis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVES

Histologic remission is a potentially valuable means of assessing disease activity and treatment response in ulcerative colitis (UC). However, the efficacy of existing therapies to achieve this outcome is unclear. We performed a systematic review and meta-analysis of histologic outcomes in UC randomized controlled trials and examined the relationship between histologic and endoscopic outcomes.

METHODS

MEDLINE, EMBASE, CENTRAL, and the Cochrane IBD Register were searched for randomized controlled trials of aminosalicylates, corticosteroids, immunosuppressives, biologics, and small molecules. Histologic and endoscopic remission and response data were independently extracted and pooled using binomial-normal random-effect or fixed-effect models. Pooled efficacy estimates were calculated as risk ratios (RRs) using the Mantel-Haenszel method. Univariable and multivariable random-effect meta-regression models examined factors associated with histologic remission.

RESULTS

Seventy-four studies (68 induction and 7 maintenance) were identified. Topical aminosalicylate enemas [37.2%, 95% confidence interval (CI), 29.0-46.3] and suppositories (44.9%, 95% CI, 28.9-62.3) had the highest induction of histologic remission rates. Aminosalicylate enemas (RR = 4.14, 95% CI, 2.35-7.31), aminosalicylate suppositories (RR = 3.94, 95% CI, 1.26-12.32), and budesonide multimatrix (RR = 1.47, 95% CI 1.08-1.99) had higher histologic remission rates than placebo. Data were lacking for biologics and immunosuppressives. The pooled histologic remission rate for placebo in induction studies was 10.4% (95% CI, 7.1-15.2). Histologic and endoscopic remission correlated strongly (r = 0.66; 95% CI, 0.50-0.78). In multivariate analysis of placebo-arm data, less severe clinical disease activity and corticosteroid use were associated with higher histologic remission rates. Similarly, mild clinical disease activity was associated with higher histologic remission rates when active-arm data were analyzed.

CONCLUSIONS

Histologic remission rates for current UC treatments ranged from 15.0% to 44.9% according to drug class and patient population with the highest rates observed for topical aminosalicylates. Placebo remission rates were low with relatively narrow CIs. These data provide benchmarks to inform future trial design. Histologic remission is a potential treatment target in clinical practice.

Prediction of steroid demand in the treatment of patients with ulcerative colitis by immunohistochemical analysis of the mucosal microenvironment and immune checkpoint: role of macrophages and regulatory markers in disease severity

We aimed to characterize the mucosal immune microenvironment and immune checkpoint of Ulcerative colitis (UC) by immunohistochemistry with correlation to prognosis: requirement of second-line steroid-therapy within the 2-years after diagnosis (SR). A series of 72 cases included 56 UC, 43 non-SR (with first-line treatment 5-ASA) and 13 SR, 11 infectious colitis and 5 normal colonic biopsies. Normal mucosa was characterized by low infiltrates but high BTLA and TNFRSF14. Compared to normal, UC had increased pan-immune-markers of CD3, CD8, FOXP3, PD-1, CD68, CD16, CD163, PTX3 and CD11C but had decreased BTLA (P < 0.05); by GSEA analysis comparable results were found in an independent UC gene-expression-data set (GSE38713). Compared to infectious, UC had higher CD4, CD8, PTX3 and CD11C but lower BTLA (P < 0.05). Compared to non-SR, SR had lower FOXP3 + Tregs (Odds-Ratio = 0.114, P = 0.002), PD-1 (OR = 0.176, P = 0.002) and CD163/CD68 M2-ratio (OR, 0.019, P = 0.019) but higher CD68 + pan-macrophages (OR = 6.034, P = 0.002). Higher Baron endoscopic and Geboes histologic disease activity scores also correlated with SR. In summary, UC was characterized by increased pan-immune-markers, normal TNFRSF14 and low BTLA. SR had increased CD68 + pan-macrophages but lower immune inhibitors of FOXP3 + Tregs, PD-1 and CD163/CD68 M2-macrophage ratio. In conclusion, alterations of the immune homeostasis mechanisms are relevant in the UC pathogenesis and steroid-requiring situation.

Correlation and concordance measures between clinical, endoscopic and histological scores activity in Crohn's disease under treatment

Aim: Our aim was to evaluate the correlation and concordance measures between clinical, endoscopic and histologic remission in Crohn's disease (CD) under treatment. Method: Twenty-four patients with CD under treatment were included in a prospective consecutive cross-sectional study from January to September 2018. Clinical activity was assessed by Crohn's Disease Activity Index (CDAI). All of the patients were submitted an ileocolonoscopy with biopsy and classified by Simple Endoscopic Score (SES-CD). Histologic activity was assessed by Global Histologic Activity Score (GHAS) modified. Remission was considered with CDAI <150; SES-CD ≤2 and GHAS ≤4. Results: Clinical remission was established in 53%, however, only 50% had mucosal healing (MH) and 70% had inflammatory histologic activity. Correlation between endoscopic and histological measures was strong and positive (σ = 0.73, p < .0003). The concordance remission agreement between SES-CD and GHAS was weak with (κ) = 0.3 (IC 95%: -0.09; 0.69). The greatest disparity arose when clinical activity (CDAI) was compared with histological measures (σ = 0.20, p = .45), (κ) = 0.26 (IC = -0.03; 0.56). Conclusion: The score SES-CD correlates well with histological score GHAS in CD under treatment, however, there is low concordance between both mainly in patients with anti-TNFs treatment. CDAI score had low correlation and concordance with histological score GHAS. In this sample, patients under treatment and without symptoms had low MH and histologic healing.

What is the role of histopathology in the evaluation of disease activity in Crohn's disease?

Assessment of disease activity is essential for developing and determining appropriate therapy in patients with Crohn's disease. Currently, clinical and endoscopic treatment targets have been proposed, whereas histologic assessment of disease activity is not recommended in expert guidelines. Histologic assessment of disease activity has emerged as an important tool in ulcerative colitis as persistent histological inflammation is associated with clinical relapse, corticosteroid use, hospitalisation, and development of dysplasia. Similar data for Crohn's disease is limited but emerging literature suggests that histologic evaluation of disease activity may have value. This review summarizes the recent literature regarding histologic evaluation of disease activity in Crohn's disease. Correlation between histologic, endoscopic, and other markers of disease activity are discussed. Histologic scoring systems in Crohn's disease are described and practical guidance is provided to gastroenterologists and pathologists on how to report and interpret histologic data.

Which evidence for a treat to target strategy in ulcerative colitis?

The main therapeutic goal of in ulcerative colitis is to maintain disease remission. The new concept of deep remission implies also a complete mucosal healing. Histological assessment of disease in UC seems to be an important prognostic factor to predict disease outcome. In this article we review current definitions of mucosal healing, histological healing, histological remission and available histological scores assessing histological activity of disease in ulcerative colitis. Comparison between mucosal healing and histological remission shows that histological remission is a better prognostic factor than mucosal healing to predict outcome in ulcerative colitis and could be a new therapeutic goal in ulcerative colitis but actually histology is not a target due to lack of evidence of clinical utility. Some investigations are needed to clearly defined histological remission and to determine its role in therapeutic strategy. Futhermore histological assessment remains an invasive exploration and other alternative as faecal markers are discuss to predict ulcerative outcome.