Endoscopy in inflammatory bowel disease: from guidelines to real life

Imaging Agents for PET of Inflammatory Bowel Disease: A Review

Inflammatory bowel disease (IBD), which encompasses ulcerative colitis and Crohn disease, is a chronic inflammatory disorder resulting from an aberrant immune response, though its exact cause is unknown. The current mainstay standard of care for the diagnosis and surveillance of IBD is endoscopy. However, this methodology is invasive and images only superficial tissue structures, revealing very little about the molecular drivers of inflammation. Accordingly, there is an unmet need for noninvasive imaging tools that provide reliable and quantitative visualization of intestinal inflammation with high spatial and molecular specificity. In recent years, several PET agents for imaging IBD have been reported. Such agents allow noninvasive visualization and quantification of dynamic molecular inflammatory processes in vivo. This review focuses on recent advancements in the development of PET tracers for imaging biomarkers of interest in IBD pathogenesis, such as cell-surface molecules that are overexpressed on immune cells and cytokines that perpetuate inflammatory signaling.

Proteomic Analysis Identifies Three Reliable Biomarkers of Intestinal Inflammation in the Stools of Patients With Inflammatory Bowel Disease

BACKGROUND

Faecal biomarkers have emerged as important tools in managing of inflammatory bowel disease [IBD], which includes Crohn's disease [CD] and ulcerative colitis [UC].

AIM

To identify new biomarkers of gut inflammation in the stools of IBD patients using a proteomic approach.

METHODS

Proteomic analysis of stools was performed in patients with both active CD and CD in remission and in controls by 2-DIGE and MALDI-TOF/TOF MS. An ELISA was used to confirm results in a second cohort of IBD patients and controls.

RESULTS

2-DIGE analysis detected 70 spots in the stools of patients with active CD or patients in remission CD and in controls. MALDI-TOF/TOF MS analysis identified 21 proteins with Chymotrypsin C, Gelsolin and Rho GDP-dissociation inhibitor 2 [RhoGDI2] best correlating with the levels of intestinal inflammation. Results were confirmed in a second cohort of IBD patients and controls [57 CD, 60 UC, 31 controls]. The identified faecal markers significantly correlated with the severity of intestinal inflammation in IBD patients [SES-CD in CD, Mayo endoscopic subscore in UC] [CD; Chymotrypsin-C: r = 0.64, p < 0.001; Gelsolin: r = 0.82, p < 0.001; RhoGDI2: r = 0.64, p < 0.001; UC; Chymotrypsin-C: r = 0.76, p < 0.001; Gelsolin: r = 0.75, p < 0.001; RhoGDI2: r = 0.63, p < 0.001]. Moreover, ROC analysis showed that Gelsolin [p < 0.0002] and RhoGDI2 [p < 0.0001] in CD, and RhoGDI2 [p = 0.0004] in UC, have higher sensitivity and specificity than faecal calprotectin in discriminating between patients and controls.

CONCLUSIONS

We show for the first time that 2-DIGE is a reliable method to detect proteins in human stools. Three novel faecal biomarkers of gut inflammation have been identified that display good specificity and sensitivity for identifying IBD and significantly correlate with IBD severity.

Automatically detecting Crohn's disease and Ulcerative Colitis from endoscopic imaging

BACKGROUND

The SI-CURA project (Soluzioni Innovative per la gestione del paziente e il follow up terapeutico della Colite UlceRosA) is an Italian initiative aimed at the development of artificial intelligence solutions to discriminate pathologies of different nature, including inflammatory bowel disease (IBD), namely Ulcerative Colitis (UC) and Crohn's disease (CD), based on endoscopic imaging of patients (P) and healthy controls (N).

METHODS

In this study we develop a deep learning (DL) prototype to identify disease patterns through three binary classification tasks, namely (1) discriminating positive (pathological) samples from negative (healthy) samples (P vs N); (2) discrimination between Ulcerative Colitis and Crohn's Disease samples (UC vs CD) and, (3) discrimination between Ulcerative Colitis and negative (healthy) samples (UC vs N).

RESULTS

The model derived from our approach achieves a high performance of Matthews correlation coefficient (MCC) > 0.9 on the test set for P versus N and UC versus N, and MCC > 0.6 on the test set for UC versus CD.

CONCLUSION

Our DL model effectively discriminates between pathological and negative samples, as well as between IBD subgroups, providing further evidence of its potential as a decision support tool for endoscopy-based diagnosis.

Could Mucosal TNF Transcript as a Biomarker Candidate Help Optimize Anti-TNF Biological Therapy in Patients With Ulcerative Colitis?

Anti-tumor necrosis factor (TNF) biological therapy has generally been accepted as a standard therapeutic option in inflammatory bowel disease (IBD) patient who are refractory to steroids or immunomodulators. However, the primary and secondary nonresponse rates to anti-TNF bioagents in patients with IBD are high. To improve the response rate, anti-TNF bioagents must be offered to the appropriate IBD patients, and the withdrawal of anti-TNF bioagents needs to be done at the right time. In this context, reliable and reproducible biomarkers can provide important supportive information for clinicians to make correct decisions based on the patient’s individual situation. In this review, we summarized the current understanding of using mucosal TNF transcript (TNF) to improve the precision of anti-TNF biological therapy strategies in patients with ulcerative colitis (UC). Analysis of published literature showed that mucosal TNF could affect the precision of the early identification of candidates who will benefit from anti-TNF therapy prior to treatment, the assessment of response and mucosal healing, and the prediction of discontinuation of anti-TNF biological therapy and relapse after drug withdrawal. Challenges and limitations of using mucosal TNF as a biomarker in applying individualized anti-TNF biological therapy in patients with UC still remain and need to be further investigated.

Perindopril/Ambrosin Combination Mitigates Dextran Sulfate Sodium-Induced Colitis in Mice: Crosstalk between Toll-like Receptor 4, the Pro-Inflammatory Pathways, and SIRT1/PPAR-γ Signaling

Colitis is one of the inflammatory states that affect the intestinal wall and may even predispose to malignancy due to chronic irritation. Although the etiology of colitis is not yet fully explored, a combination of genetic and environmental factors is strongly incriminated. Perindopril is an angiotensin-converting enzyme inhibitor that is used for the management of a wide range of cardiovascular diseases. Ambrosin is a sesquiterpene lactone that was proven to have beneficial effects in disorders characterized by inflammatory nature. The objective of this study is to make a comparison between the effects of perindopril or ambrosin on dextran sulfate sodium (DSS)-induced colitis in mice and to explore the effect of their combination. The present findings indicate that each ambrosin or perindopril alone or in combination is able to ameliorate oxidative stress and suppress the proinflammatory pathways in the colonic tissues of DSS-treated mice via mechanisms related to toll-like receptor 4/nuclear factor kappa B signaling and modulation of peroxisome proliferator-activated receptor gamma/sirtuin-1 levels. In addition, each ambrosin or perindopril alone or in combination inhibits apoptosis and augments the mediators of autophagy in DSS-treated mice. These effects are reflected in the amelioration of the histopathological and electron microscopic changes in the colonic tissues. Interestingly, the most remarkable effects are those encountered with the perindopril/ambrosin combination compared to the groups treated with each of these agents alone. In conclusion, the perindopril/ambrosin combination might represent an effective modality for mitigation of the pathogenic events and the clinical sequelae of colitis.

Impact of COVID-19 on Healthcare Resource Utilisation Among Patients with Inflammatory Bowel Disease in the USA

BACKGROUND AND AIMS

The impact of the COVID-19 pandemic on patients with inflammatory bowel disease [IBD] is largely unknown. We characterised the impact of COVID-19 on IBD care by conducting an analysis of US health care claims data.

METHODS

We obtained de-identified, open-source, health insurance claims data, from January 2019 to December 2020, from the Symphony Health Integrated Dataverse for US adults with IBD, and measured the rates per 1000 patients of five outcomes: colonoscopies; new biologic or small molecule treatment initiations or treatment switches; new biologic or small molecule treatment initiations or treatment switches in patients who had a colonoscopy within the previous 60 days; IBD-related surgeries; and telehealth consultations.

RESULTS

For 2019 and 2020, 1.32 million and 1.29 million patients with IBD, respectively, were included in the analysis. In March-April 2020, the rates of colonoscopies [17.39 vs 34.44], new biologic or small molecule treatment initiations or switches in patients who had a colonoscopy within the previous 60 days [0.76 vs 1.18], and IBD-related surgeries [2.33 vs 2.99] per 1000 patients were significantly decreased versus January-February 2020; significant year on year decreases versus 2019 were also observed. Telehealth utilisation increased in March 2020 and remained higher than in 2019 up to December 2020.

CONCLUSIONS

Reduction in colonoscopies and subsequent initiation/switching of treatments during the COVID-19 pandemic suggest lost opportunities for therapy optimisation which may have an impact on longer-term patient outcomes. Increased utilisation of telehealth services may have helped address gaps in routine clinical care.

Development and Testing of a New Simplified Endoscopic Mucosal Assessment for Crohn's Disease: The SEMA-CD

OBJECTIVES

Endoscopic mucosal improvement is the gold standard for assessing treatment efficacy in clinical trials of Crohn's disease. Current endoscopic indices are not routinely used in clinical practice. The lack of endoscopic information in large clinical registries limits their use for research. A quick, easy, and accurate method is needed for assessing mucosal improvement for clinicians in real-world practice. We developed and tested a novel simplified endoscopic mucosal assessment for Crohn's disease (SEMA-CD).

METHODS

We developed a 5-point scale for ranking endoscopic severity of ileum and colon based on Simple Endoscopic Score for Crohn's disease (SES-CD). Central readers were trained to perform SES-CD and SEMA-CD. Pediatric patients with Crohn's disease undergoing colonoscopy were enrolled. Video recordings of colonoscopies were de-identified and randomly assigned to blinded central readers. The SES-CD and SEMA-CD were scored for each video. The SES-CD was considered the validated standard for comparison. Correlation was assessed with Spearman rho, inter- and intrarater reliability with kappa statistics.

RESULTS

Fifty-seven colonoscopies were read a total of 212 times. Correlation between SEMA-CD and SES-CD was strong (rho = 0.98, P < 0.0001). Inter-rater reliability for SEMA-CD was 0.80, and intrarater reliability was 0.83. Central readers rated SEMA-CD as easier than SES-CD.

CONCLUSION

The SEMA-CD accurately and reproducibly correlates with the standard SES-CD. Central readers viewed SEMA-CD as easier than SES-CD. Use of SEMA-CD in practice should enable collecting mucosal improvement information in large populations of patients. This will improve the quality of research that can be conducted in clinical registries. External validation is needed.

Artificial Intelligence Enhances Studies on Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn’s disease (CD), is an idiopathic condition related to a dysregulated immune response to commensal intestinal microflora in a genetically susceptible host. As a global disease, the morbidity of IBD reached a rate of 84.3 per 100,000 persons and reflected a continued gradual upward trajectory. The medical cost of IBD is also notably extremely high. For example, in Europe, it has €3,500 in CD and €2,000 in UC per patient per year, respectively. In addition, taking into account the work productivity loss and the reduced quality of life, the indirect costs are incalculable. In modern times, the diagnosis of IBD is still a subjective judgment based on laboratory tests and medical images. Its early diagnosis and intervention is therefore a challenging goal and also the key to control its progression. Artificial intelligence (AI)-assisted diagnosis and prognosis prediction has proven effective in many fields including gastroenterology. In this study, support vector machines were utilized to distinguish the significant features in IBD. As a result, the reliability of IBD diagnosis due to its impressive performance in classifying and addressing region problems was improved. Convolutional neural networks are advanced image processing algorithms that are currently in existence. Digestive endoscopic images can therefore be better understood by automatically detecting and classifying lesions. This study aims to summarize AI application in the area of IBD, objectively evaluate the performance of these methods, and ultimately understand the algorithm–dataset combination in the studies.

Application of linked color imaging in the diagnosis of early gastrointestinal neoplasms and precancerous lesions: a review

INTRODUCTION

Minimally invasive endoscopic resection is often effective in the management of early gastrointestinal tumors. However, advanced and more effective methods of endoscopic examination are required to improve the rate of diagnosing early gastrointestinal tumors.

DISCUSSION

The development of dye-based image-enhanced endoscopy (d-IEE) and equipment-based image-enhanced endoscopy (e-IEE) has helped improve the diagnostic rate of early gastrointestinal tumor using endoscopy. In some special cases, these methods are still not accurate in diagnosing lesions. On the basis of these e-IEEs, a new endoscopic technique, linked color imaging (LCI), that combines a specific short wavelength narrow band of light with white light, has been developed.

CONCLUSION

In this article, we summarized the characteristics of LCI and the development of research regarding digestive tract examination.

PLAIN LANGUAGE SUMMARY

Application of linked color imaging in early gastrointestinal neoplasms At present, the complete diagnosis of early gastrointestinal tumors and precancerous lesions can be made by gastrointestinal endoscopy. With the improvement of therapeutic instruments and operators' experience, endoscopic therapy can often achieve significant effect in the treatment of early gastrointestinal tumors. The development and spread of equipment-based image-enhanced endoscopy (e-IEE) mode has helped improve the diagnosis rate of early gastrointestinal tumors under endoscopy. However, in some special cases, these methods are still not accurate for the diagnosis of lesions. On the basis of these E-IEEs, a new endoscopic technique, linked color imaging (LCI), has been developed, which combines a specific short wavelength narrow band of light with white light. LCI can significantly improve the diagnostic rate of all types of gastrointestinal mucosal lesions. Tumor lesions and inflammatory lesions can be distinguished by observing the mucosal microvascular structure and color difference. LCI helps detect early gastrointestinal mucosal lesions by taking advantage of the differences in light absorption of different wavelengths and contrast of enhanced colors in the later stage.

Cannabinoids and Inflammations of the Gut-Lung-Skin Barrier

Recent studies have identified great similarities and interferences between the epithelial layers of the digestive tract, the airways and the cutaneous layer. The relationship between these structures seems to implicate signaling pathways, cellular components and metabolic features, and has led to the definition of a gut-lung-skin barrier. Inflammation seems to involve common features in these tissues; therefore, analyzing the similarities and differences in the modulation of its biomarkers can yield significant data promoting a better understanding of the particularities of specific signaling pathways and cellular effects. Cannabinoids are well known for a wide array of beneficial effects, including anti-inflammatory properties. This paper aims to explore the effects of natural and synthetic cannabinoids, including the components of the endocannabinoid system, in relation to the inflammation of the gut-lung-skin barrier epithelia. Recent advancements in the use of cannabinoids as anti-inflammatory substances in various disorders of the gut, lungs and skin are detailed. Some studies have reported mixed or controversial results, and these have also been addressed in our paper.

Evolving role of endoscopy in inflammatory bowel disease: Going beyond diagnosis

Inflammatory bowel disease, encompassing Crohn’s disease (CD) and ulcerative colitis, are chronic immune-mediated inflammatory bowel diseases (IBD) that primarily affect the gastrointestinal tract with periods of activity and remission. Large body of evidence exist to strengthen the prognostic role of endoscopic evaluation for both disease activity and severity and it remains the gold standard for the assessment of mucosal healing. Mucosal healing has been associated with improved clinical outcomes with prolonged remission, decreased hospitalization, IBD-related surgeries and colorectal cancer risk. Therefore, endoscopic objectives in IBD have been incorporated as part of standard care. With the known increased risk of colorectal cancer in IBD, although prevention strategies continue to develop, regular surveillance for early detection of neoplasia continue to be paramount in IBD patients’ care. It is thanks to evolving technology and visualization techniques that surveillance strategies are continuously advancing. Therapeutic endoscopic options in IBD have also been expanding, from surgery sparing therapies such as balloon dilation of fibrostenotic strictures in CD to endoscopic mucosal resection of neoplastic lesions. In this review article, we discuss the current evidence on the use of endoscopy as part of standard of care of IBD, its role in surveillance of neoplasia, and the role of interventional endoscopic therapies.

Rediscovering histology: what is new in endoscopy for inflammatory bowel disease?

The potential of endoscopic evaluation in the management of inflammatory bowel diseases (IBD) has undoubtedly grown over the last few years. When dealing with IBD patients, histological remission (HR) is now considered a desirable target along with symptomatic and endoscopic remission, due to its association with better long-term outcomes. Consequently, the ability of endoscopic techniques to reflect microscopic findings in vivo without having to collect biopsies has become of upmost importance. In this context, a more accurate evaluation of inflammatory disease activity and the detection of dysplasia represent two mainstay targets for IBD endoscopists. New diagnostic technologies have been developed, such as dye-less chromoendoscopy, endomicroscopy, and molecular imaging, but their real incorporation in daily practice is not yet well defined. Although dye-chromoendoscopy is still recommended as the gold standard approach in dysplasia surveillance, recent research questioned the superiority of this technique over new advanced dye-less modalities [narrow band imaging (NBI), Fuji intelligent color enhancement (FICE), i-scan, blue light imaging (BLI) and linked color imaging (LCI)]. The endoscopic armamentarium might also be enriched by new video capsule endoscopy for monitoring disease activity, and high expectations are placed on the application of artificial intelligence (AI) systems to reduce operator-subjectivity and inter-observer variability. The goal of this review is to provide an updated insight on contemporary knowledge regarding new endoscopic techniques and devices, with special focus on their role in the assessment of disease activity and colorectal cancer surveillance.

Predictive value of blood concentration of biologics on endoscopic inactivity in inflammatory bowel disease: A systematic review

BACKGROUND

Although blood concentration of biologics is an important composition of disease management in inflammatory bowel disease (IBD) patients, complexity and uncertainty of biological management encourage many disputes in predicting the outcome of IBD patients through blood concentration of biologics.

AIM

To verify the predictive value of blood concentration of biologics on endoscopic inactivity in IBD patients under different situations.

METHODS

We searched PubMed/MEDLINE, Embase, and Web of Science up to May 2020 and identified IBD patients as the research cohort as well as the correlations between blood concentration of biologics and endoscopic inactivity in IBD patients as the research direction.

RESULTS

A total of 23 articles with 30 clinical studies and 1939 IBD patients were included. The predictive cut-off value of blood concentration of infliximab on mucosal healing should be 2.7-10.6 μg/mL in IBD. Blood concentration of infliximab reaching 5.0-12.7 μg/mL or more increased the probability of fistula healing/closure in perianal fistulizing Crohn's disease. Blood concentration of adalimumab reaching 7.2-16.2 μg/mL or more could predict mucosal healing in IBD. The predictive cut-off value of blood concentration of adalimumab on fistula healing/closure should be 5.9-9.8 μg/mL in perianal fistulizing Crohn's disease. Blood concentration of vedolizumab surpassing 25.0 μg/mL indicated mucosal healing in ulcerative colitis patients under maintenance therapy and the predictive cut-off value of blood concentration on mucosal healing or endoscopic remission under induction therapy in IBD could be 8.0-28.9 μg/mL.

CONCLUSION

Blood concentration of biologics should not be utilized to predict endoscopic inactivity of IBD independently due to discrepancies in clinical studies, whereas conducting therapeutic drug monitoring intensively contributes to precise therapy.

Treat-to-target approach in the management of inflammatory Bowel disease

With the advent of biologic and small molecule therapies, there has been a substantial change in the treatment of inflammatory bowel disease. These advances have had a great impact in preventing disease progression, intestinal damage and, therefore, have contributed to a better quality of life. Discordance between symptom control and mucosal healing has been demonstrated. This has led to the search for new disease control targets. The treat to target strategy, based on expert recommendations and now a randomized controlled trial, has determined that clinical and endoscopic remission should be the goal of therapy. Biomarkers (fecal calprotectin) can be a surrogate target. Although histological healing has shown benefits, there is inadequate evidence and inadequate therapy for that to be a fixed goal at this time. This review will focus on therapeutic goals, according to the evidence currently available, and evaluate strategies to achieve them.