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

Absence of Paneth Cell Metaplasia to Predict Clinical Relapse in Ulcerative Colitis with Endoscopically Quiescent Mucosa

BACKGROUND

Paneth cells play multiple roles in maintaining intestinal homeostasis. However, the clinical role of Paneth cell metaplasia (PCM) in ulcerative colitis (UC) remains unclear. We aimed to investigate the relationship between PCM and relapse in patients with UC and compare the usefulness of PCM with other histological indexes, including mucin depletion (MD) and basal plasmacytosis (BP).

METHODS

Patients with UC in clinical remission (CR) who underwent colonoscopy to confirm a Mayo endoscopic subscore (MES) ≦1 with biopsies from the distal colon were enrolled into this retrospective cohort study. Biopsy samples were evaluated for histological findings of PCM, MD, and BP. Clinical relapse was defined as partial Mayo score ≧3 or medication escalation. Multivariate analysis was performed to determine independent predictors of relapse among the three histological findings, MES, and patient background, and relapse prediction models were generated.

RESULTS

Eighty-three patients were enrolled in this study (MES 0, n = 47; MES 1, n = 36). The number of PCM cases was significantly higher in patients with prolonged CR than that in those with relapse (p = 0.01). Multivariate analysis showed that the absence of PCM and MD were related to relapse in all the patients. In patients with MES 1, the absence of PCM was the only risk factor significantly and independently associated with relapse (hazard ratio, 4.51 [1.15-17.7]; p = 0.03).

CONCLUSION

The absence of PCM was a histological risk factor for relapse in patients with MES 1, implying a protective role for PCM in remission and a new index for mucosal healing.

To STRIDE or not to STRIDE: a critique of "treat to target" in ulcerative colitis

INTRODUCTION

The STRIDE consensus intends to complement the clinical endpoint with an endoscopic endpoint of mucosal healing and others as treatment targets in ulcerative colitis. If these targets are not reached, STRIDE requires dose or timing adjustments or switching the medication. This narrative review provides a critique of this concept.

AREAS COVERED

We analyze and discuss the limitations of current endpoints as targets, their currently limited achievability, and the lacking evidence from controlled trials relating to 'treat to target.' The relevant publications in PubMed were identified in a literature review with the key word 'ulcerative colitis.'

EXPERT OPINION

In ulcerative colitis, the standard clinical target is measured traditionally by the MAYO-score, but in variable combinations of patient and physician reported outcomes as well as also different definitions of the endoscopic part. Only a score of 0 is more stringent than clinical remission but is only achieved by a minority of patients in first and even less in second line therapy. The concept is not based on clear evidence that patients indeed benefit from appropriate escalation of treatment. Until the STRIDE approach is proven to be superior to standard treatment focusing on clinical well-being, the field should remain reluctant.

Ulcerative colitis: the healing power of macrophages

Ulcerative colitis (UC) is a chronic and debilitating disorder that falls under the broad category of inflammatory bowel disease (IBD). Therefore, affects the colon and rectum, resulting in inflammation and ulcers in the lining of these organs. Over the years, there has been a significant shift in the management of UC. The focus has moved from achieving symptom-free daily living to attaining mucosal healing. Mucosal healing means completely restoring the colon and rectum's lining, significantly reducing the risk of complications and relapse. Macrophages are a crucial component of the immune system that play a vital role in the regeneration and repair of colonic ulcers. These immune cells are responsible for production of a variety of cytokines and growth factors that facilitate tissue repair. Macrophages are responsible for maintaining a balance between inflammation and healing. When this balance is disrupted, it can lead to chronic inflammation and tissue damage, exacerbating UC symptoms. Thus, this review aims to investigate the contribution of macrophages to mucosal repair and remission maintenance in UC patients.

Mesalazine dose modification based on faecal calprotectin levels in patients with ulcerative colitis in clinical remission

BACKGROUND

Faecal calprotectin (FC) shows an excellent correlation with endoscopic and histological activity of ulcerative colitis (UC) and it is the best predictor of clinical relapse. Our aim was to evaluate the usefulness of modifying the dose of mesalazine based on FC levels, in clinical practice.

METHODS

Retrospective, single-centre study in UC patients in clinical remission while treated with mesalazine which dosage was decreased (DOWN) or increased (UP) according to FC levels. The main endpoint was the long-term maintenance of clinical remission.

RESULTS

A total of 56 patients were included (39 DOWN, 17 UP). In the DOWN group, the median baseline dose of mesalazine was 3.6g/day and the median baseline FC was 36μg/g. After a median follow-up of 22 months, 28% required rescue therapy. The cumulative relapse-free survival after tapering was 91% and 82% at 12 and 24 months, respectively. In the UP group, the median baseline dose of mesalazine was 2.4g/day, with a median baseline FC of 524μg/g. After a median follow-up of 12 months, 29% required rescue therapy. The cumulative relapse-free survival after dose increase was 86% and 72% at 12 and 24 months, respectively.

CONCLUSIONS

Mesalazine dose modification based on FC monitoring seems to be a safe strategy in patients with UC in clinical remission, with a probability of clinical relapse around 20% at two years.

Comprehensive overview of novel chemical drugs for ulcerative colitis: focusing on phase 3 and beyond

INTRODUCTION

Despite the growing number of highly efficacious biologics and chemical drugs for ulcerative colitis (UC), steroid-free disease control is still difficult to achieve in subgroups of patients due to refractoriness, adverse events, primary or secondary failure. New treatments are therefore still required in order to optimize clinical management of patients with UC.

AREAS COVERED

The efficacy and safety of both currently available and newly developed small molecules have been summarized. The PubMed database and clinicaltrials.gov were considered in order to search for phase 2b and 3 trials on new chemical drugs for UC. The study drugs reviewed included Janus kinases (JAK) and sphingosine-1-phosphate receptor (S1Pr) inhibitors, α4 integrin antagonist, and micro-RNA-124 upregulators.

EXPERT OPINION

Rapidity of onset, low immunogenicity, and safety are the main characteristics of small molecules currently available or under evaluation for treatment patients with UC. Among the currently available chemical drugs, the selective JAK and the S1Pr inhibitors are characterized by a good safety profile combined with the ability to induce clinical remission in UC. A relatively low frequency of endoscopic improvement and healing currently appears associated with their use, being higher in UC patients treated with S1Pr inhibitor Etrasimod. Overall, additional new safe and effective drugs are still required in order to optimize disease control in a larger majority of UC patients.

Harnessing the Vnn1 pantetheinase pathway boosts short chain fatty acids production and mucosal protection in colitis

OBJECTIVE

In the management of patients with IBD, there is a need to identify prognostic markers and druggable biological pathways to improve mucosal repair and probe the efficacy of tumour necrosis factor alpha biologics. Vnn1 is a pantetheinase that degrades pantetheine to pantothenate (vitamin B₅, a precursor of coenzyme A (CoA) biosynthesis) and cysteamine. Vnn1 is overexpressed by inflamed colonocytes. We investigated its contribution to the tolerance of the intestinal mucosa to colitis-induced injury.

DESIGN

We performed an RNA sequencing study on colon biopsy samples from patients with IBD stratified according to clinical severity and modalities of treatment. We generated the VIVA mouse transgenic model, which specifically overexpresses Vnn1 on intestinal epithelial cells and explored its susceptibility to colitis. We developed a pharmacological mimicry of Vnn1 overexpression by administration of Vnn1 derivatives.

RESULTS

VNN1 overexpression on colonocytes correlates with IBD severity. VIVA mice are resistant to experimentally induced colitis. The pantetheinase activity of Vnn1 is cytoprotective in colon: it enhances CoA regeneration and metabolic adaptation of colonocytes; it favours microbiota-dependent production of short chain fatty acids and mostly butyrate, shown to regulate mucosal energetics and to be reduced in patients with IBD. This prohealing phenotype is recapitulated by treating control mice with the substrate (pantethine) or the products of pantetheinase activity prior to induction of colitis. In severe IBD, the protection conferred by the high induction of VNN1 might be compromised because its enzymatic activity may be limited by lack of available substrates. In addition, we identify the elevation of indoxyl sulfate in urine as a biomarker of Vnn1 overexpression, also detected in patients with IBD.

CONCLUSION

The induction of Vnn1/VNN1 during colitis in mouse and human is a compensatory mechanism to reinforce the mucosal barrier. Therefore, enhancement of vitamin B₅-driven metabolism should improve mucosal healing and might increase the efficacy of anti-inflammatory therapy.

Fourier-Transform Infra-Red Microspectroscopy Can Accurately Diagnose Colitis and Assess Severity of Inflammation

The diagnosis and management of inflammatory bowel disease relies on histological assessment, which is costly, subjective, and lacks utility for point-of-care diagnosis. Fourier-transform infra-red spectroscopy provides rapid, non-destructive, reproducible, and automatable label-free biochemical imaging of tissue for diagnostic purposes. This study characterises colitis using spectroscopy, discriminates colitis from healthy tissue, and classifies inflammation severity. Hyperspectral images were obtained from fixed intestinal sections of a murine colitis model treated with cell therapy to improve inflammation. Multivariate analyses and classification modelling were performed using supervised and unsupervised machine-learning algorithms. Quantitative analysis of severe colitis showed increased protein, collagen, and nucleic acids, but reduced glycogen when compared with normal tissue. A partial least squares discriminant analysis model, including spectra from all intestinal layers, classified normal colon and severe colitis with a sensitivity of 91.4% and a specificity of 93.3%. Colitis severity was classified by a stacked ensemble model yielding an average area under the receiver operating characteristic curve of 0.95, 0.88, 0.79, and 0.85 for controls, mild, moderate, and severe colitis, respectively. Infra-red spectroscopy can detect unique biochemical features of intestinal inflammation and accurately classify normal and inflamed tissue and quantify the severity of inflammation. This is a promising alternative to histological assessment.

A systematic monitoring approach to biologic therapies in inflammatory bowel disease: patients' and physicians' preferences and adherence

OBJECTIVES

Treatment of patients with inflammatory bowel disease (IBD) should aim at achieving mucosal healing. However, monitoring schedules to support this goal remain undefined. We aimed to identify patients' and physicians' preferences regarding monitoring strategy and investigated the feasibility of such a strategy.

METHODS

Elements considered relevant for monitoring were identified in questionnaire surveys among 1) patients with IBD receiving biologic agents (n = 172) and 2) their physicians (n = 87). Adherence to a monitoring strategy incorporating these elements was investigated in a retrospective cohort of patients with IBD treated with biologic agents (n = 139).

RESULTS

Patients considered blood and stool samples, endoscopies, and magnetic resonance imaging (MRI) to be relevant aspects of monitoring their disease. However, patients also considered stool samples and endoscopies unpleasant. Physicians considered blood samples (99%), medical consultations (99%), fecal calprotectin (85%), endoscopy (78%), and MRI (71%) to be important aspects of IBD monitoring but considered endoscopies and MRI relevant only at clinical signs of relapse. A review of the clinical use of monitoring strategies including the elements identified above revealed high adherence for blood samples and disease activity indices (92%), but low adherence for fecal calprotectin (38%), therapeutic drug monitoring (38%), and endoscopies (32%).

CONCLUSION

Important tools for evaluating mucosal healing (e.g., endoscopy) were rated highly unpleasant by patients, and physicians found endoscopies/MRI relevant only in case of relapse. These findings were reflected by low rates of adherence to use of these monitoring tools. In defining monitoring schedules to help achieve treatment goals, these important barriers must be addressed.

Histological Scores in Patients with Inflammatory Bowel Diseases: The State of the Art

The histological assessment has been advocated as a detailed and accurate measure of disease activity in inflammatory bowel diseases (IBD). In ulcerative colitis (UC), histological activity has been demonstrated to be associated with higher rates of relapse, prolonged corticosteroid use and long-term complications, even when endoscopic remission is achieved. Therefore, histological healing may represent a potential treatment target. Several histological scores have been developed and are available today. The Robarts histopathology index (RHI) and the Nancy index (NI) are the only two recommended by the European Crohn’s and Colitis Organization (ECCO) for use in patients with UC. Conversely, in Crohn’s disease (CD), the discontinuous nature of lesions has limited standardized histological assessment. Most of the available histological scoring systems in CD are complex and not validated. The aim of this review is to comprehensively summarize the latest evidence regarding histological scoring systems in IBD. We guide the reader through understanding the importance of an accurate microscopic evaluation using validated scoring systems, highlighting the strengths and pitfalls of each score. The priorities of future research needs are also addressed.

Short-term effectiveness and safety of tofacitinib in ulcerative colitis - real world data from tertiary medical centers in Israel

BACKGROUND

We sought to define the effectiveness and safety of tofacitinib in a real-world (RW) cohort of Israeli patients with moderate to severe ulcerative colitis (UC).

METHODS

This was a multi-center retrospective observational cohort study (2019-2020) to assess the effectiveness and safety of tofacitinib induction and maintenance therapy up to 26 weeks. Clinical response and remission were defined as a reduction in Simple Clinical Colitis Activity Index (SCCAI) or partial Mayo score (PMS) of ≥3 points, and SCCAI ≤2 or a PMS ≤1, respectively.

RESULTS

We included 73 patients, 47% male; median age 26 years [IQR: 19.5-39.5], disease duration 7 years [IQR: 2.5-14.5], follow-up 7.1 months [IQR: 3-12], 91% biologics-experienced, and 74% ≥ 2-biologics. Half of patients used concomitant corticosteroids (CS). Overall, 56.1% discontinued therapy due to either lack of response and/or adverse events (AEs), median time to discontinuation - 9.7 months [IQR 3.4-16]. Overall, response, remission, and CS-free-remission were achieved in 47.6%, 20.6%, and 17.5% of patients, respectively. At early maintenance (week 26), response, remission, and CS-free-remission were achieved in 65%, 22.5%, and 20% of patients, respectively. At week 26, tofacitinib 10 mg BID was still used in 43%. Seventeen patients (23.2%) had an adverse event including herpes zoster- 2.7%, hospitalization- 12.3%, and colectomy- 2.7%.

CONCLUSIONS

Tofacitinib was effective in achieving CS-free-remission in about 1/5 of highly biologics -experienced patients with UC. Despite a considerable proportion of patients maintained on tofacitinib 10 mg bid, it was well tolerated and safe. Earlier positioning of tofacitinib in the therapeutic algorithm may result in improved outcomes.

Host transcriptome signatures in human faecal-washes predict histological remission in patients with IBD

BACKGROUND

Colonoscopy is the gold standard for evaluation of inflammation in inflammatory bowel diseases (IBDs), yet entails cumbersome preparations and risks of injury. Existing non-invasive prognostic tools are limited in their diagnostic power. Moreover, transcriptomics of colonic biopsies have been inconclusive in their association with clinical features.

AIMS

To assess the utility of host transcriptomics of faecal wash samples of patients with IBD compared with controls.

METHODS

In this prospective cohort study, we obtained biopsies and faecal-wash samples from patients with IBD and controls undergoing lower endoscopy. We performed RNAseq of biopsies and matching faecal-washes, and associated them with endoscopic and histological inflammation status. We also performed faecal mass-spectrometry proteomics on a subset of samples. We inferred cell compositions using computational deconvolution and used classification algorithms to identify informative genes.

RESULTS

We analysed biopsies and faecal washes from 39 patients (20 IBD, 19 controls). Host faecal-transcriptome carried information that was distinct from biopsy RNAseq and faecal proteomics. Transcriptomics of faecal washes, yet not of biopsies, from patients with histological inflammation were significantly correlated to one another (p=5.3×10-12). Faecal-transcriptome had significantly higher statistical power in identifying histological inflammation compared with transctiptome of intestinal biopsies (150 genes with area under the curve >0.9 in faecal samples vs 10 genes in biopsy RNAseq). These results were replicated in a validation cohort of 22 patients (10 IBD, 12 controls). Faecal samples were enriched in inflammatory monocytes, regulatory T cells, natural killer-cells and innate lymphoid cells.

CONCLUSIONS

Faecal wash host transcriptome is a statistically powerful biomarker reflecting histological inflammation. Furthermore, it opens the way to identifying important correlates and therapeutic targets that may be obscured using biopsy transcriptomics.

A Patient Self-Made Point-of-Care Fecal Test Improves Diagnostic Accuracy Compared with Fecal Calprotectin Alone in Inflammatory Bowel Disease Patients

Background: Monitoring inflammatory bowel disease patients may be challenging. Fecal calprotectin is one of the most performed tests. Other fecal biomarkers are less used in clinical practice. Rapid fecal tests that could be performed by patients may be a useful strategy to closely monitor disease activity. Methods: We performed a prospective observational study including consecutive inflammatory bowel disease patients referred for colonoscopy in a single center. Certest FOB + Transferrin + Calprotectin + Lactoferrin^® (Certest Biotec S.L, Zaragoza, Spain), a one-step point-of-care test which simultaneously detects these four biomarkers was performed. Endoscopic inflammatory activity was defined using the Mayo score (≥1) in ulcerative colitis, SES-CD (>3) and Rutgeerts scores (≥1) for Crohn’s disease. Results: Out of a total of 106 patients (56.5% female, mean age 51 years), 54 (50.9%) were diagnosed with ulcerative colitis and 52 (49.1%) with Crohn’s disease. Endoscopic activity was detected in 42 patients (39.0%). Fecal calprotectin provided the best sensitivity (97.6%), with limited specificity (34.4%). Compared to calprotectin, the other 3 fecal biomarkers showed better specificity (87.5–92.1%) and lower sensitivity (45.2–59.5%). Patients with a negative result in all biomarkers (19/106—17.9%) had 100% (CI 95% 97.4–100) negative predictive value, while patients with the 4 biomarkers positive (13/106—12.3%) had 100% (CI 95% 96.1–100) positive predictive value of endoscopic inflammatory activity. AUROC of this 4 biomarker point-of-care test was 0.845 (95% CI 0.771–0.920), significantly higher than the AUROCs of any of the 4 biomarkers. Conclusions: This test may be a useful strategy to monitor inflammatory activity in clinical practice by excluding or prioritizing patients in need of a colonoscopy.

IBD metabonomics predicts phenotype, disease course, and treatment response

Metabonomics in inflammatory bowel disease (IBD) characterizes the effector molecules of biological systems and thus aims to describe the molecular phenotype, generate insight into the pathology, and predict disease course and response to treatment. Nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), and integrated NMR and MS platforms coupled with multivariate analyses have been applied to create such metabolic profiles. Recent advances have identified quiescent ulcerative colitis as a distinct molecular phenotype and demonstrated metabonomics as a promising clinical tool for predicting relapse and response to treatment with biologics as well as fecal microbiome transplantation, thus facilitating much needed precision medicine. However, understanding this complex research field and how it translates into clinical settings is a challenge. This review aims to describe the current workflow, analytical strategies, and associated bioinformatics, and translate current IBD metabonomic knowledge into new potential clinically applicable treatment strategies, and outline future key translational perspectives.

Medical therapy versus surgery in moderate-to-severe ulcerative colitis

Ulcerative colitis, a chronic inflammatory condition that affects the colon from rectum to caecum, is characterized by periods of increased bowel movements, blood in feces, rectal urgency, tenesmus, and abdominal pain, with periods of remission and flares of disease, which negatively impact quality of life. A number of therapeutic options are available for patients with moderate-to-severe ulcerative colitis, however, no clear treatment algorithm exists. Therapeutic goals include short-term benefits for patients (i.e., the reduction/absence of symptoms, essentially stool frequency and rectal bleeding) and long-term benefits (i.e., sustained clinical remission, steroid-free remission, and mucosal healing). Therapies currently approved and available for the treatment of moderate-to-severe ulcerative colitis include monoclonal antibodies such as those targeting anti-tumor necrosis factor α (i.e., infliximab, adalimumab, golimumab), anti-adhesion molecules (i.e., vedolizumab), anti-interleukin 12/23 agents (i.e., ustekinumab), and Janus Kinase inhibitors (i.e., tofacitinib). Surgical approaches should also be considered in patients refractory to medical therapy or with complications (including toxic megacolon or colonic dysplasia/cancer). This review provides an overview of currently available treatment options for patients with moderate-to-severe ulcerative colitis and summarizes factors that should be considered during the therapeutic decision.

Early Intervention in Ulcerative Colitis: Ready for Prime Time?

Growing evidence shows that ulcerative colitis (UC) is a progressive disease similar to Crohn’s disease (CD). The UC-related burden is often underestimated by physicians and a standard step-up therapeutic approach is preferred. However, in many patients with UC the disease activity is not adequately controlled by current management, leading to poor long-term prognosis. Data from both randomized controlled trials and real-world studies support early intervention in CD in order to prevent disease progression and irreversible bowel damage. Similarly, an early disease intervention during the so-called “window of opportunity” could lead to better outcomes in UC. Here, we summarize the literature evidence on early intervention in patients with UC, highlighting strengths and limitations of this approach.