Chromoendoscopy: what is its true value for ulcerative colitis surveillance?

Advanced imaging technologies are enabling targeted biopsies or endoscopic resections due to better visualization of the mucosal architecture. This new concept of 'smart biopsies' is in particular important for patients with higher risk for development cancer (e.g. ulcerative colitis) but can also be beneficial for screening purposes. This short review will focus on new imaging modalities like chromoendoscopy, digital chromoendoscopy, high-definition endoscopy and confocal laser endomicroscopy in the lower GI tract which will be crucial in the future to detect colorectal neoplasia earlier then before.     

Recent advances in targeted endoscopic imaging: Early detection of gastrointestinal neoplasms

Molecular imaging has emerged as a new discipline in gastrointestinal endoscopy.This technology encompasses modalities that can visualize disease-specific morphological or functional tissue changes based on the molecular signature of individual cells.Molecular imaging has several advantages including minimal damage to tissues,repetitive visualization,and utility for conducting quantitative analyses.Advancements in basic science coupled with endoscopy have made early detection of gastrointestinal cancer possible.Molecular imaging during gastrointestinal endoscopy requires thedevelopment of safe biomarkers and exogenous probes to detect molecular changes in cells with high specificity anda high signal-to-background ratio.Additionally,a high-resolution endoscope with an accurate wide-field viewing capability must be developed.Targeted endoscopic imaging is expected to improve early diagnosis and individual therapy of gastrointestinal cancer.     

Capsule endoscopy for patients with coeliac disease

Introduction: Coeliac disease is an autoimmune mediated condition in response to gluten. A combination of innate and adaptive immune responses results in villous shortening in the small bowel (SB) that can be morphologically picked up on capsule endoscopy. It is the only imaging modality that can provide mucosal views of the entire SB, while histology is generally limited to the proximal SB. Radiological modalities are not designed to pick up changes in villous morphology.

Areas covered: In this review, we provide a comprehensive analysis on the justified use of small bowel capsule endoscopy (SBCE) in the assessment of patients with coeliac disease; compare SBCE to histology, serology, and symptomatology; and provide an overview on automated quantitative analysis for the detection of coeliac disease. We also provide insight into future work on SBCE in relation to coeliac disease.

Expert commentary: SBCE has opened up new avenues for the diagnosis and monitoring of patients with coeliac disease. However, larger studies with new and established coeliac disease patients and with greater emphasis on morphological features on SBCE are required to better define the role of SBCE in the setting of coeliac disease.     

Advanced imaging and therapeutic endoscopy

From the early days of gastrointestinal endoscopy, there has been remarkable progress in imaging technology. High-definition endoscopes are now part of the standard armamentarium and a variety of other advanced imaging modalities jostle for space. However, the objective of each of these remains much the same; the enablement of the endoscopist to accurately characterize early gastrointestinal mucosal lesions, which are beyond the capability of standard devices. The benefit of doing so, may be manifold. First, during surveillance of gastrointestinal malignancy, the endoscopist may choose to eschew random biopsies in favor of targeted ones from areas of suspicious mucosa. Second, early mucosal lesions may be detected, which are typically amenable to endoscopic therapy. The ultimate result is improved clinical outcomes and in many cases, the avoidance of surgery. The goal of this review is to summarize for the reader, the most important technologies in advanced endoscopic imaging and their applicability to clinical practice with emphasis on their functioning, implementation, and effect on therapeutic endoscopy.     

Future expectations in digestive endoscopy: competition with other novel imaging techniques

Digestive endoscopy has been evolving from primary diagnostic to extensive therapeutic modalities in the management of gastrointestinal diseases. The present endoscopic imaging includes (A) standard endoscopy alone and /or with adjunct technologies such as point enhancement, e.g. confocal endomicroscopy and field enhancement technologies such as chromoendoscopy, NBI and FICE and (B) endoscopic ultrasound. Other novel imaging technologies including virtual colonoscopy or CT/MR colonography, CT or MRI enterography and capsule endoscopy have also been developed. This article reviews the diagnostic and therapeutic role of digestive endoscopy and future directions of digestive endoscopy are discussed. Digestive endoscopy is also compared with emerging novel imaging techniques in gastrointestinal diseases such as capsule endoscopy and CT colonography. The fact that digestive endoscopy has become a multidisciplinary specialty combining advances in all fields (radiology, bioengineering, surgery and gastroenterology) is highlighted.     

The role of endoscopy in eosinophilic esophagitis: from diagnosis to therapy

Introduction: Eosinophilic esophagitis (EoE) has arisen as a common disorder in current clinical and endoscopic gastroenterology practice.

Areas covered: A comprehensive review of the literature to summarize and update different aspects related with the use of endoscopy in the diagnostic workout and treatment of pediatric and adult EoE patients is conducted.

Expert commentary: Endoscopic features in EoE are frequently subtle, so were inadverted in some initial reports of the disease. Literature has described a wide number of EoE-associated features, systematized in the EREFS classification, which standardized the grade and severity of exudates, rings, edema, furrows, and strictures. The insufficient reliability of these features to predict eosinophilic inflammation still makes biopsies essential in diagnosing or monitoring EoE.

EoE causes half of the food impactions requiring endoscopy; food impaction leads to EoE diagnosis in up to half of cases. Long term consequences of EoE include esophageal remodeling leading to strictures and narrowing, thus impairing symptoms and needs dilation. Recognizing the risks from dilation in EoE required carrying out a safe technique to avoid the high complication rate reported in the early literature. Endoscopic dilation should be considered in patients with esophageal narrowing and dysphagia/food impaction unresponsive to diet or drugs-based anti-inflammatory treatment.     

Surveillance strategies for colitis-associated cancer: state of the art and future perspectives

Introduction: Colitis-associated cancer (CAC) represents a concrete risk of morbidity and mortality in patients with long lasting inflammatory bowel diseases. Surveillance colonoscopy is a rapidly evolving research field with profound changes from the traditional approach based on scheduled controls and random biopsy protocols.

Areas covered: A literature search was performed using PubMed/Embase to review the latest evidence supporting the need for surveillance colonoscopy. By focusing on the most promising recent advances in this field, we provide a state-of-the-art overview of the current gold standards for the diagnosis and management of colitis-associated dysplasia.

Expert commentary: Evidence-based and emerging data have questioned the efficacy and effectiveness of both standard surveillance colonoscopy and random biopsy protocols. The latest guidelines endorse early initiation of surveillance programs, risk-profiling assessment of colonoscopy intervals and standardized use of advanced imaging modalities to detect early dysplasia. Current trends clearly reveal increased attention to direct visualization and endoscopic management of visible dysplastic lesions, even in patients with longstanding colitis. Emerging technological advances in gastrointestinal endoscopy are expected to change the endoscopic surveillance protocols in the near future.     

Endoscopic imaging: emerging optical techniques for the detection of colorectal neoplasia.

PURPOSE OF REVIEW: Advances in bioengineering have spawned various imaging modalities which have revolutionized endoscopy. Some of these technologies provide real-time, high-resolution, subcellular imaging. This review provides an update on these technologies and their role in the evaluation of colorectal neoplasia. RECENT FINDINGS: Narrow band imaging has been shown to visualize capillary patterns in early cancer and is complementary to magnification endoscopy. Optical coherence tomography has been used to evaluate neoplastic progression and distinguish Crohn's from ulcerative colitis. Confocal endomicroscopy has been shown to accurately predict neoplastic changes in polyps and identify areas of neoplasia in patients with colitis. Among the spectroscopic techniques, autofluorescence is best studied in the colon and has been used to identify adenomas and dysplasia in inflammatory bowel disease. Endocytoscopy is a relatively new technology but shows promise in distinguishing neoplastic lesions. SUMMARY: Recently a number of imaging technologies have arisen that have the potential to enhance our detection of colorectal neoplasia. Several of these, such as autofluorescent imaging and narrow band imaging, are 'red flag' techniques which enhance our visualization of mucosal change(s). Complementary technologies, such as confocal endomicroscopy and endocytoscopy, provide subcellular imaging. Combined with a 'red flag' technique, these may transform our approach to colonoscopy, allowing the real-time detection and diagnosis of neoplasia.     

The sensitivity of fecal calprotectin in predicting deep remission in ulcerative colitis

Background: Mucosal healing is proposed as treat-to-target in ulcerative colitis (UC), even though the definition of mucosal healing remains contested as it has been suggested to be assessed by either endoscopy, histology or both. However, all definitions require an endoscopic evaluation of the mucosa. As endoscopies are invasive and uncomfortable to the patient we aimed to calibrate noninvasive predictors of mucosal inflammatory status defined by both endoscopy and histology.

Methods: UC patients (n?=?106) undergoing a sigmoid-/colonoscopy were prospectively included. Feces (fecal calprotectin, FC), blood samples (hemoglobin, C-reactive protein, orosomucoid, erythrocyte sedimentation rate, albumin) and symptom scores (Simple Clinical Colitis Activity Index, SSCAI) were collected and analyzed. The colonic mucosa was assessed by the Mayo endoscopic sub score and biopsies were obtained for a histologic grading by Geboes score. Predictive cutoff values were analyzed by receiver operating characteristics (ROC). A combined endoscopic and histologic assessment defined deep remission (Mayo =0 and Geboes ≤1) and activity (Mayo ≥2 and Geboes >3).

Results: Only FC showed a significant ROC curve (p?230. The complete ROC data is presented, enabling extraction of an FC cutoff value’s sensitivity and specificity.

Conclusions: FC predicts endoscopic and histologic assessed deep remission and inflammatory activity of colon mucosa. Neither the markers in blood nor the SCCAI performed significant ROC results.     

Prediction of submucosal gastric cancer by narrow-band imaging magnifying endoscopy

BackgroundThe features of gastric submucosal cancer revealed by magnifying endoscopy have not been reported. Aim of our study was to investigate whether magnifying endoscopy could contribute to the diagnosis of submucosal invasion.Patients and methodsIn this prospective, cross-sectional study, 197 lesions of gastric differentiated adenocarcinoma, diagnosed as mucosal cancer by conventional endoscopy, were observed by magnifying endoscopy with narrow-band imaging, paying attention to the presence of a blurry mucosal pattern and an irregular mesh pattern. After endoscopic submucosal dissection, all lesions were examined histologically and the areas of two features were estimated.ResultsAmong the lesions examined, 177 were diagnosed histologically as mucosal cancer and 20 as submucosal cancer. Multivariate logistic regression analysis confirmed that a blurry mucosal pattern (odds ratio 12.15, 95% confidence interval 3.45–42.76, p = 0.000) and an irregular mesh pattern (22.55, 4.22–120.45, p = 0.000) were independent predictors of submucosal invasion.ConclusionsNarrow band imaging magnifying endoscopic features are useful for predicting submucosal invasion in gastric cancer.     

Enhanced Mucosal Imaging and the Esophagus—Ready for Prime Time?

Innovation of endoscopic technology has recently been introduced to improve real-time visualization of mucosal architecture and subepithelial vascular structures. Since the esophagus is easily accessible using endoscopy and the length of required observation is limited, many different types of new imaging modalities have been reported and showing promising data. Early detection of neoplastic changes in the esophagus is devoted to the treatment in early stage cancer and theoretically leads to better prognosis. This review will focus on the emerging endoscopic technologies for the management of esophageal cancer.     

Image-enhanced endoscopy is specific for the diagnosis of non-erosive gastroesophageal reflux disease

Objectives: We assessed the performance characteristics of image-enhanced endoscopy with i-Scan or narrow band imaging (NBI) in patients with non-erosive gastroesophageal reflux disease (GERD) compared to controls without heartburn.

Material and methods: Image-enhanced endoscopic findings of vascularity at the squamocolumnar junction, distal esophageal micro-erosions, and non-round pit pattern at the squamocolumnar junction were assessed in cases (heartburn not responsive to PPIs, positive results on validated GERD questionnaire, no esophageal erosions, esophageal biopsies with histologic evidence of GERD (basal cell hyperplasia, elongation of papillae and dilation of intercellular spaces all required)) and in controls (no GERD symptoms or esophageal erosions).

Results: Twenty cases and 60 controls were compared. The pre-defined features were more common in cases vs. controls: vascularity RR?=?4.9 (95% CI: 2.4–10.0), specificity?=?86.7%; micro-erosions RR?=?9.7 (3.6–26.5), specificity?=?93.3%; non-round pit pattern RR?=?2.4 (1.7–3.3), specificity?=?60.0%; combination of vascularity and micro-erosions RR?=?30.0 (4.1–220), specificity?=?98.3%. These differences were consistent with both i-Scan and NBI.

Conclusions: Image-enhanced endoscopic findings of vascularity and micro-erosions were very specific for non-erosive GERD. Image-enhanced endoscopy may be useful in real-time diagnosis of non-erosive GERD when patients undergo upper endoscopy for heartburn. The relative utility of image-enhanced endoscopy vs. pH-impedance monitoring, based on efficacy, cost and patient acceptance, requires additional study.     

Diagnosing dysplasia in Barrett’s oesophagus still requires Seattle protocol biopsy in the era of modern video endoscopy: results from a tertiary centre Barrett’s dysplasia database

Abstract

Objectives: The role of random, four-quadrant biopsy (i.e. systematic biopsy) in Barrett’s oesophagus surveillance has been questioned given its drawbacks and the emergence of high-resolution endoscopy and advanced imaging modalities. Our study aims to assess whether neoplastic pathology is typically diagnosed in routine clinical practice by random, four-quadrant or targeted biopsy whilst using high-resolution endoscopy.

Methods: The Nottingham University Hospital Barrett’s oesophagus dysplasia database was retrospectively analysed. Endoscopic and histopathologic data pertaining to the initial endoscopy in which pathology was diagnosed was extracted from the medical records. The most advanced histopathologic abnormality at initial diagnosis and within twelve months were noted. The corresponding endoscopic impression at initial diagnosis was used to group cases per type of biopsy – random, four-quadrant or targeted. Pearson’s χ² test of independence was used to analyse the relationship between the type of biopsy and diagnosis, indication for endoscopy, endoscopist level and advanced techniques used.

Results: Of the 222 patients involved in the study – a higher proportion were diagnosed through random, four-quadrant biopsy (72.97%) than targeted biopsy (27.03%). 90.91% of low-grade dysplasia, 71.43% of high-grade dysplasia and 50% of intramucosal adenocarcinoma cases were diagnosed by random, four-quadrant biopsy. Across all grades of clinicians, patients were typically diagnosed through random, four-quadrant biopsy. However, amongst specialist consultant endoscopists (n?=?10) the proportion was equal.

Conclusions: Our findings strongly emphasize the importance of random, four-quadrant biopsy in the detection of not only low-grade dysplasia, but also high-grade dysplasia and early invasive carcinoma as part of Barrett’s oesophagus surveillance.     

Predictive factors of therapeutic intervention in on-call endoscopy for suspected gastrointestinal bleeding

Background and Aims: Performing an endoscopy out of hours confer significant burdens on limited health-care resources. However, not all on-call endoscopies lead to therapeutic interventions. The purpose of the present study was to analyze predictive factors for performing therapeutic intervention in patients with suspected gastrointestinal bleeding.

Methods: We reviewed and analyzed electronic medical records regarding on-call endoscopy that were prospectively collected for quality control. The subjects were patients with suspected gastrointestinal bleeding who underwent on-call endoscopies at night, on weekends and on holidays between April 2013 and January 2017 in Seoul National University Bundang Hospital. To determine predictive factors for performing therapeutic intervention, the following variables were analyzed: symptoms, patient status, coexisting disease, laboratory findings and medications. To clarify the association between the likelihood of therapeutic intervention in on-call endoscopy and AIMS65 score, the included variables were divided by cutoffs.

Results: A total of 270 patients (male: 72.6%, mean age: 62.6 years) with suspected gastrointestinal bleeding had on-call endoscopies and 153 (56.7%) patients had therapeutic intervention. Gastroscopy, colonoscopy and both endoscopic techniques were performed in 215, 42 and 13 patients, respectively. In the multivariate analysis, hematemesis (p?p?=?.033; OR, 1.958) were correlated with performing therapeutic intervention in on-call endoscopy. AIMS65 score with a cutoff of 2 was associated with the likelihood of intervention (p?=?.043).

Conclusions: Hematemesis and prolonged PT-INR were predictive factors of therapeutic intervention when on-call endoscopy was performed in patients with suspected gastrointestinal bleeding.     

Œsophagite nécrosante aiguë : une complication rare

IntroductionAcute esophageal necrosis (AEN) is a rare medical disorder, which is characterized by a diffuse black esophageal mucosal during upper gastrointestinal endoscopy which is a highly recommended diagnostic tool. Its high mortality rate requires to be quickly evocated and an early management.Case reportWe report a case of a 93-year-old patient with upper gastrointestinal bleeding. The upper endoscopy shows a grade D AEN according to the Los Angeles classification. Treatment consists of a parenteral nutritional support and an intravenous proton pump inhibitors treatment, which increase chances of a favorable outcome on endoscopic controls at 2 and 6 weeks.ConclusionAEN has to be quickly evocated in a polyvascular and old patient with upper gastrointestinal bleeding. Our experience confirms that optimal and early management allow a esophageal complete healing at 6 weeks.     

Endoscopic diagnosis of dysplasia in Barrett’s esophagus

Evaluation of: Sharma P, Hawes RH, Bansal A et al. Standard endoscopy with random biopsies versus narrow band imaging targeted biopsies in Barrett’s oesophagus: a prospective, international, randomised controlled trial. Gut 62(1), 15–21 (2013).

Barrett’s esophagus, or columnar metaplasia with gastric cardiac cells or intestinal cells, develops in the squamous epithelium of the esophageal mucosa in relation to gastroesophageal reflux. An increased risk of neoplasia justifies surveillance at regular intervals. Conventional guidelines recommend detection of areas with intestinal metaplasia or dysplasia by taking random four-quadrant biopsies at every 1 or 2 cm. Alternatively, image processing with narrow band imaging (NBI), is proposed to improve detection. This international and randomized study in persons with Barrett’s esophagus compares conventional endoscopy in white light with random four-quadrant biopsies and NBI imaging with focused biopsies only. Randomization enrolled 123 patients with Barrett’s esophagus who successively underwent exploration with the two methods. The study confirmed that NBI had the same efficacy as white light in the detection of intestinal metaplasia, with a higher proportion of dysplasia detected (30 vs 21%) and a lower number of biopsies per patient (3.6 vs 7.6).     

Nasogastric aspiration/lavage in patients with gastrointestinal bleeding: a review of the evidence

Introduction: The usefulness of nasogastric aspiration and nasogastric lavage in patients with gastrointestinal bleeding is controversial, as evidenced by conflicting recommendations, both among and within society guidelines.

Areas covered: Considering these controversies, we reviewed the evidence regarding the following questions: 1) Can nasogastric lavage stop or slow down the bleeding and improve subsequent endoscopic visualization? 2) Is nasogastric aspiration helpful for the localization of bleeding? 3) Can nasogastric aspiration identify high risk patients that might benefit from earlier endoscopy? 4) Is there evidence for benefit in terms of outcomes from using nasogastric aspiration? 5) Is nasogastric intubation safe in patients with possible esophageal varices? Our review was conducted according to PRISMA guidelines.

Expert commentary: Based on the available literature, nasogastric lavage or aspiration cannot be routinely recommended unless a large properly designed randomized trial (which is currently lacking) proves otherwise. It is a painful and time-consuming procedure with no demonstrated benefit for the patient in terms of outcomes. Other clinical and laboratory parameters, and risk scores, are less invasive and are effective for guiding the stratification and management of patients, while pre-endoscopic erythromycin infusion is a good if not better alternative for improving visualization of the stomach.     

Monitoring of small bowel Crohn’s disease

Introduction: In recent years, the therapeutic paradigm in Crohn’s disease has shifted from a mere symptom-oriented approach, to aiming to healing of the underlying inflammation and prevention of long-term structural complications. Such ‘treat-to-target’ approach may allow for a more stable disease course with less hospitalizations, lower requirement for surgery and improved quality of life. In Crohn’s disease, the small bowel is affected in the majority of patients; frequently, Crohn’s involves only the small bowel, which remains inaccessible to conventional ileocolonoscopic techniques. Thus, non-invasive monitoring techniques are crucial for accurate disease assessment.

Areas covered: This review addresses the indications and clinical implications of non-invasive small bowel monitoring modalities (magnetic resonance enterography, intestinal ultrasound, capsule endoscopy) in the assessment and management of Crohn’s disease.

Expert commentary: This review addresses the limitations of the current knowledge and future areas of research, including the possible utilization of transmural healing as an imaging target and the need to establish clear quantitative target values to guide treatment by imaging findings in Crohn’s disease.     

Diagnostic value of endoscopy for the diagnosis of giardiasis and other intestinal diseases in patients with persistent diarrhea from tropical or subtropical areas

Objective. Upper endoscopy has been suggested as a valuable tool in the diagnosis of giardiasis. The aim of this study was to compare two methods based on endoscopy, i.e. microscopy of duodenal fluid and histology, with a fluorescent-antibody assay for the detection of Giardia lamblia cysts in stool specimens. The role of endoscopy in the identification of other causes of chronic diarrhea acquired during travel abroad was also evaluated. Material and methods. Thirty-one patients (9 F, 22 M, median age 39 years, range 19–63 years) with persistent diarrhea after returning from tropical or subtropical areas agreed to undergo upper gastrointestinal endoscopy before and after treatment. Lower gastrointestinal endoscopy was subsequently performed. Three stool samples from each patient were examined using the direct fluorescent-antibody assay (DFA) for the detection of G. lamblia, and by routine methods for other protozoal and bacterial enteric pathogens. Each patient underwent upper endoscopy and biopsies and duodenal fluid samples were taken. In 12 patients a further lower endoscopy was performed. Results. In 16 patients G. lamblia was detected in stool samples by DFA (relative sensitivity: 100%). Histology of duodenal biopsies and microscopy of duodenal fluids allowed diagnosis of giardiasis to be made in only 8, and 3 patients, respectively (relative sensitivities: 21% and 44%). Besides giardiasis, upper endoscopic examination revealed an alternative diagnosis (tropical sprue), whereas six additional diagnoses were made by colonoscopy. In six patients the cause of chronic diarrhea remained unclear. Conclusions. Compared to stool examinations using DFA, upper endoscopy is less sensitive for the diagnosis of giardiasis. In patients with negative stool examinations, lower endoscopy yields relevant diagnoses more often than upper endoscopy.     

Endoscopic detection of early lower gastrointestinal cancer

The prognosis for patients with malignancies of the lower gastrointestinal tract is strictly dependent on early detection of premalignant and malignant lesions. What should an ideal screening and surveillance colonoscopy be able to accomplish? The technique should allow detection of large but also discrete mucosal alterations. Ideally, endoscopic discrimination between neoplastic and non-neoplastic lesions would be possible during the ongoing procedure. At present, endoscopy can be performed with powerful new endoscopes. Comparable to the rapid development in chip technology, the optical features of the newly designed endoscopes offer resolutions, which allow new surface details to be seen. In conjunction with chromoendoscopy, the newly discovered tool video colonoscopy is much easier and more impressive today than with the previously used fibre-optic endoscopes. Recently, new endoscopic technologies such as narrow band imaging, endocytoscopy, or confocal laser endoscopy have allowed the discovery of a whole new world of image details which will surely improve the diagnostic yield in the field of early malignancies. This review summarises newly available technologies and clinical data about the diagnosis of early lower gastrointestinal cancers.