Review: Food-induced mucosal alterations visualized using endomicroscopy.

Confocal laser endomicroscopy (CLE) is a novel technique allowing real time in vivo microscopy during standard endoscopy. Recently, acute mucosal alterations after food administration visualized by CLE have been linked to symptoms in irritable bowel syndrome (IBS). Interestingly, the observed reactions occurred in subjects without demonstrable allergic sensitization to food-this is in line with mechanistic research showing local but not systemic allergic sensitization to foods in an animal model for IBS. Here, European experts conducting CLE with food administration provide a narrative review of the available literature and propose practical guidance on the use of this technique. CLE allows physicians to observe acute mucosal reactions after the application of food to the duodenal mucosa in patients with functional gastrointestinal disorders. Some open-label interventions show a symptomatic benefit when patients exclude the nutrient that triggered an acute mucosal reaction. However, many technical, mechanistic, and clinical questions remain unanswered to date. Technically, the interobserver variability and learning curve requires systematic evaluation and criteria or cutoffs for alterations require validation. Mechanistic studies are needed to enhance our understanding of the mechanisms underlying observed alterations. Finally, rigorous blinded controlled studies are needed to assess a link of these observed alterations with symptom generation. CLE offers a platform allowing scientific insights related to food induced acute mucosal alterations. However, many questions remain unanswered, and more research is warranted to understand the role of acute mucosal alterations visualized upon food administration in IBS pathophysiology and treatment.

Hemospray® (hemostatic powder TC-325) as monotherapy for acute gastrointestinal bleeding: a multicenter prospective study.

Background: Hemostatic powders are used as second-line treatment in acute gastrointestinal (GI) bleeding (AGIB). Increasing evidence supports the use of TC-325 as monotherapy in specific scenarios. This prospective, multicenter study evaluated the performance of TC-325 as monotherapy for AGIB. Methods: Eighteen centers across Europe and USA contributed to a registry between 2016 and 2022. Adults with AGIB were eligible, unless TC-325 was part of combined hemostasis. The primary endpoint was immediate hemostasis. Secondary outcomes were rebleeding and mortality. Associations with risk factors were investigated (statistical significance at P≤0.05). Results: One hundred ninety patients were included (age 51-81 years, male: female 2:1), with peptic ulcer (n=48), upper GI malignancy (n=79), post-endoscopic treatment hemorrhage (n=37), and lower GI lesions (n=26). The primary outcome was recorded in 96.3% (95% confidence interval [CI]: 92.6-98.5) with rebleeding in 17.4% (95%CI 11.9-24.1); 9.9% (95%CI 5.8-15.6) died within 7 days, and 21.7% (95%CI 15.6-28.9) within 30 days. Regarding peptic ulcer, immediate hemostasis was achieved in 88% (95%CI 75-95), while 26% (95%CI 13-43) rebled. Higher ASA score was associated with mortality (OR 23.5, 95%CI 1.60-345; P=0.02). Immediate hemostasis was achieved in 100% of cases with malignancy and post-intervention bleeding, with rebleeding in 17% and 3.1%, respectively. Twenty-six patients received TC-325 for lower GI bleeding, and in all but one the primary outcome was achieved. Conclusions: TC-325 monotherapy is safe and effective, especially in malignancy or post-endoscopic intervention bleeding. In patients with peptic ulcer, it could be helpful when the primary treatment is unfeasible, as bridge to definite therapy.

Gastrointestinal adverse reaction to food (GARF) and endoscopic confocal laser endomicroscopy (eCLE).

BACKGROUND AND STUDY AIMS: Gastrointestinal adverse reaction to food (GARF) is reported frequently in the general population and even more in patients with disorders of the gut brain axis. However, there is a significant difference between self-reported and objective proven GARF. The aim of the study was to characterize a mucosal correlate of GARF by endoscopic confocal laser endomicroscopy (eCLE) with duodenal food challenge (DFC). PATIENTS AND METHODS: In an observational and proof of concept study we evaluated 71 patients with disorders of the gut brain axis without (group I, n=19) and with (group II, n=52) GARF by eCLE and DFC. Spontaneous and food induced transfer of fluorescein into duodenal lumen was detected 10 minutes following intravenously application of fluorescein and 10 minutes after DFC. RESULTS: According to Rom IV, the patients (group I/II) could be classified as irritable bowel syndrome (IBS) 32%/31%, functional abdominal pain without changes in bowel movement 47 %/48 %, functional abdominal bloating/distension 0 %/10 %, functional diarrhea 5 %/ 2 %, and unspecified functional bowel disorder 16 %/10 %, respectively. 21 %/27 % of the patients responded with a fluorescein leakage into the duodenal lumen before and 74 %/69 % following to DFC. Frequency rank order of food components that induced a response were soy (55.5 %/60 %), wheat (60 %/45.5 %), egg (35.7 %/8.3), milk (30 %/18.2 %) and yeast (10 %/6.6 %), respectively. Histology of duodenal biopsies, number, form and distribution of intraepithelial lymphocytes and mucosal mast cells as well as mast cell function were normal. Overall, 14 %/79 % reported main symptom benefit following a food exclusion therapy according to eCLE and DFC that was significant different between the groups. CONCLUSION: The results of our study indicate that eCLE with DFC is a technique to clinically evaluate patients with disorders of the gut brain axis and GARF resulting in a high proportion of patients reporting symptom benefit upon food exclusion dietary advice focussed on the results of eCLE.

Eosinophilic esophagitis and duodenal food challenge - evaluation through endoscopic confocal laser endomicroscopy.

BACKGROUND: Endoscopic confocal laser endomicroscopy (eCLE) is an established technique that allows clinical evaluation of mucosal integrity by fluorescein leaking through the mucosa upon duodenal food challenge (DFC). Analysis of eCLE with DFC in eosinophilic esophagitis (EoE) would be interesting to evaluate epithelial barrier dysfunction also in other regions of the gastrointestinal tract and to characterize potential individual food allergens that trigger the esophageal inflammation. METHODS: In an observational and proof of concept study we evaluated 9 patients with histologically proven EoE by eCLE and DFC. Severity of symptoms were graduated according to the validated symptom-based EoE activity index. The endoscopic appearance of the esophagus was described according to the Endoscopic Reference Score System (ERERS). Spontaneous and food induced transfer of fluorescein into duodenal lumen were detected 10 minutes following intravenously application of fluorescein and 10 minutes after DFC. Food allergens were yeast, egg, soy, milk, and wheat, respectively. Local application of sodium chloride solution 10 % to the duodenal mucosa before DFC served as a control. Patients responding to DFC received a dietary exclusion therapy according to the results of DFC. RESULTS: We investigated 9 patients with EoE (8 men, 49.7±13.8, 36-76 years). Symptom-based EoE activity index was 79±27.4, 33-100. In all patients EoE was confirmed by histology with number of esophageal mucosal eosinophilic granulocytes > 15/HPF, (91.4±77.4, 42-263). Mean ERERS score was 4.5±1.3, 3-7. None of the patients was aware of any food intolerance. eCLE revealed one patient with spontaneous transfer of i. v. fluorescein into duodenal lumen before DFC ("leaky gut"). 40 DFC were performed in the remaining 8 patients of whom 5 patients (61 %) responded to DFC. Rank order of fluorescein leakage upon DFC was wheat and milk in 37.5 % each, soy in 25 %, and egg in 12.5 %. The patients were treated by PPI (n=9), esophageal bouginage (n=5) and/or local corticoid therapy (n=3). The 5 patients responding to DFC received an additional food exclusion dietary advice focussed on the results of DFC. All patients reported a reduction of their symptoms. EoE activity indexes of patients with positive DFC were 73.7+28.6, 33-100 before and 22.7+37.9, 0-79 four weeks after food exclusion. CONCLUSION: The findings of our proof of concept study suggest that eCLE with DFC may be an interesting tool to further evaluate patients with EoE. This technique has the potential to identify patients who may benefit from an additional individual dietary therapy.

Retrospective comparison of G-EYE balloon-colonoscopy with standard colonoscopy for increased adenoma detection rate and reduced polyp removal time.

Background and study aims The newly introduced G-EYE colonoscope (G-EYE) employs a balloon, installed at the bending section of a standard colonoscope (SC), for increasing adenoma detection and stabilizing the colonoscope tip during intervention. This retrospective work explores the effect of introducing G-EYE into an SC endoscopy room, in terms of adenoma detection and polyp removal time. Patients and methods This was a single-center, retrospective study. Historical data from patients who underwent colonoscopy prior to, and following, introduction of G-EYE into a particular endoscopy room were collected and analyzed to determine adenoma detection rate (ADR), adenoma per patient (APP), and polyp removal time (PRT), in each of the SC and G-EYE groups. Results Records of 1362 patients who underwent SC and 1433 subsequent patients who underwent G-EYE colonoscopy in the same endoscopy unit by the same endoscopists were analyzed. Following G-EYE introduction, overall ADR increased by 37.5 % ( P  < 0.0001) from 39.2 % to 53.9 %, the serrated adenoma rate increased by 47.3 % from 27.9 % to 41.1 % ( P  < 0.0001), and the APP increased by 50.6 % from 0.79 to 1.19 ( P  < 0.0001). The number of advanced adenomas increased by 32.7 %, from 19.6 % to 26.0 % of all adenomas ( P  < 0.0001). With G-EYE, average PRT was reduced overall by 29.5 % ( P  < 0.0001), and particularly for endoscopic mucosal resection (EMR) by 37.5 % for polyps measuring ≥ 5 mm to ≤ 20 mm ( P  < 0.0001) and by 29.4 % for large polyps > 20 mm ( P  < 0.0001). Conclusions Introduction of G-EYE to an SC endoscopy room yielded considerable increase in ADR and notable reduction in PRT, particularly with the EMR technique. G-EYE balloon colonoscopy might increase the effectiveness of colorectal cancer screening and surveillance colonoscopy, and can shorten the time of endoscopic intervention.

Artificial Intelligence Enabled Histological Prediction of Remission or Activity and Clinical Outcomes in Ulcerative Colitis.

BACKGROUND & AIMS: Microscopic inflammation has significant prognostic value in ulcerative colitis (UC); however, its assessment is complex with high interobserver variability. We aimed to develop and validate an artificial intelligence (AI) computer-aided diagnosis system to evaluate UC biopsies and predict prognosis. METHODS: A total of 535 digitalized biopsies (273 patients) were graded according to the PICaSSO Histologic Remission Index (PHRI), Robarts, and Nancy Histological Index. A convolutional neural network classifier was trained to distinguish remission from activity on a subset of 118 biopsies, calibrated on 42 and tested on 375. The model was additionally tested to predict the corresponding endoscopic assessment and occurrence of flares at 12 months. The system output was compared with human assessment. Diagnostic performance was reported as sensitivity, specificity, prognostic prediction through Kaplan-Meier, and hazard ratios of flares between active and remission groups. We externally validated the model in 154 biopsies (58 patients) with similar characteristics but more histologically active patients. RESULTS: The system distinguished histological activity/remission with sensitivity and specificity of 89% and 85% (PHRI), 94% and 76% (Robarts Histological Index), and 89% and 79% (Nancy Histological Index). The model predicted the corresponding endoscopic remission/activity with 79% and 82% accuracy for UC endoscopic index of severity and Paddington International virtual ChromoendoScopy ScOre, respectively. The hazard ratio for disease flare-up between histological activity/remission groups according to pathologist-assessed PHRI was 3.56, and 4.64 for AI-assessed PHRI. Both histology and outcome prediction were confirmed in the external validation cohort. CONCLUSION: We developed and validated an AI model that distinguishes histologic remission/activity in biopsies of UC and predicts flare-ups. This can expedite, standardize, and enhance histologic assessment in practice and trials.

Food intolerance in patients with functional abdominal pain: Evaluation through endoscopic confocal laser endomicroscopy.

Background and study aims Gastrointestinal symptoms assumed to be caused by food intolerance are reported frequently in the general population. There is a significant difference between self-reported and objective proven food intolerance, as shown by placebo-controlled, double-blind, randomized trials. This discrepancy may be overcome by endoscopic confocal laser endomicroscopy (eCLE). Patients and methods In an observational study we evaluated 34 patients with functional abdominal pain and adverse reaction to food by eCLE and local duodenal food challenge for the first time. Spontaneous and food-induced transfer of fluorescein into the duodenal lumen was detected 10 minutes after intravenously application of fluorescein and 10 minutes after duodenal food challenge (DFC). Results Of the patients, 67.6 % responded with a fluorescein leakage into the duodenal lumen. Frequency rank order of food antigens that induced a response were soy (50 %), wheat (46.1 %), milk (20 %), egg (12 %), and yeast (11.5 %), respectively. Of the patients, 23.5 % showed spontaneous leakage of fluorescein, suggesting leaky gut syndrome. Histology of duodenal biopsies and mast cell function were normal. Overall, 69.5 % of patients improved with food exclusion therapy and 13 % were symptom-free according to eCLE. Conclusions The results of our study indicate that eCLE is a clinically useful tool to evaluate patients with functional abdominal pain and adverse reaction to food and to create individualized dietary therapy with clinical benefit for patients.

Endoscopic laser endomicroscopy and "leaky gut" in patients with functional gastrointestinal symptoms and food intolerance.

BACKGROUND: Intestinal epithelial barrier dysfunction ("leaky gut syndrome", LGS) is thought to play a major role in the pathogenesis of disorders of the gut brain axis. Endoscopic confocal laser endomicroscopy (eCLE) is an objective measure to test duodenal permeability. We applied this technique in patients with functional gastrointestinal symptoms and food intolerance to characterize the proportion of patients with LGS. MATERIAL AND METHODS: In an observational study, we evaluated 85 patients with functional gastrointestinal symptoms and food intolerance. Gastrointestinal symptoms were classified according to Rom IV into functional abdominal pain (FAP), irritable bowel syndrome (IBS), irritable bowel syndrome diarrhea dominant (IBS-D), irritable bowel syndrome constipation dominant (IBS-C), irritable bowel syndrome with mixed stool (IBS-M), functional abdominal bloating (FAB), functional diarrhea (FD) and unclassified (NC). During eCLE, spontaneous transfer of intravenously applied fluorescein into duodenal lumen (LGS) and following duodenal food challenge (DFC) were analyzed. Blood analysis comprised parameters of mast cell function, histology of duodenal mucosal biopsies analysis of mucosal inflammation, intraepithelial lymphocytes (IELs) as well as number, distribution and morphology of mast cells. RESULTS: 24 patients (9 IBS, 9 FAP, 3 FAB, 1 FD, 2 NC), showed LGS, 50 patients (14 IBS-D, 4 IBS-C, 3 IBS-M, 23 FAP, 3 FAB, 3 NC) had no LGS but responded to DFC and 11 patients (6 NC, 3 FAP, 1 FAB, 1 FD) had no LGS and no response to DFC. The proportion of subgroups with/or without spontaneous leakage of fluorescein (+LGS/-LGS) were IBS-LGS/IBS+LGS 67%/33%, FAP-LGS/FAP+LGS 72%/28%,FAB-LGS/FAB+LGS 50%/50%, NC-LGS/NC+LGS 60%/40%. Subgroup analysis revealed no significant differences for all parameters tested. CONCLUSION: As a proof of concept, the results of our study indicate that eCLE is a clinical useful tool to evaluate patients with disorders of the gut brain axis and those suspicious of LGS. However, the clinical significance of LGS remains unclear. The study should be an incentive to perform a randomized study including healthy controls.

Endoscopic management of patients with high-risk colorectal colitis-associated neoplasia: a Delphi study.

BACKGROUND AND AIMS: Current guidelines recommend endoscopic resection of visible and endoscopically resectable colorectal colitis-associated neoplasia (CAN) in patients with inflammatory bowel disease (IBD). However, patients with high-risk CAN (HR-CAN) are often not amenable to conventional resection techniques, and a consensus approach for the endoscopic management of these lesions is presently lacking. This Delphi study aims to reach consensus among experts on the endoscopic management of these lesions. METHODS: A 3-round modified Delphi process was conducted to reach consensus among worldwide IBD and/or endoscopy experts (n = 18) from 3 continents. Consensus was considered if ≥75% agreed or disagreed. Quality of evidence was assessed by the criteria of the Cochrane Collaboration group. RESULTS: Consensus was reached on all statements (n = 14). Experts agreed on a definition for CAN and HR-CAN. Consensus was reached on the examination of the colon with enhanced endoscopic imaging before resection, the endoscopic resectability of an HR-CAN lesion, and endoscopic assessment and standard report of CAN lesions. In addition, experts agreed on type of resections of HR-CAN (< 20 mm, >20 mm, with or without good lifting), endoscopic success (technical success and outcomes), histologic assessment, and follow-up in HR-CAN. CONCLUSIONS: This is the first step in developing international consensus-based recommendations for endoscopic management of CAN and HR-CAN. Although the quality of available evidence was considered low, consensus was reached on several aspects of the management of CAN and HR-CAN. The present work and proposed standardization might benefit future studies.

Technical Note: First Use of Endonasal Confocal Laser Endomicroscopy - Feasibility and Proof of Concept

Abstract Introduction Probe-based confocal laser endomicroscopy (p-CLE) is a method for real-time in vivo visualization of mucosal changes on a cellular level. Due to the size of the endoscopes, it was mainly used in the gastrointestinal tract so far. First investigations on head and neck carcinoma described the oropharyngeal application. The further miniaturization of the laser probe now allows endonasal application and, thus, first experiences with the investigation of endonasal neoplasms. Objectives The aim of the present investigation is to elucidate, based on the morphological criteria validated in the oropharynx, whether these criteria be transferred in a similar way to the endonasal mucosa. Methods We conducted p-CLE (Cellvizio, Paris, France) with intravenous fluorescein staining in endoscopic sinus surgery in a patient with sinonasal inverted papilloma and a histologically confirmed squamous cell carcinoma. We compared the cellular visualization of pathological changes with those of healthy mucosa in the same specimen, and also with our former findings in the oropharynx. Results Endonasal p-CLE proved to be quite feasible in the surgical setting, and the transfer of malignancy criteria in analogy to histological examination could be optically retraced. Furthermore, additional criteria for tissue dignity assessment were obtained. Conclusion Our results suggest that endonasal application of p-CLE represents a valuable extension of the diagnostic repertoire available to date by an additional realtime analysis of the nasal mucosa. This is of particular value in surgically challenging anatomical areas such as the paranasal sinuses.

Technical Note: First Use of Endonasal Confocal Laser Endomicroscopy - Feasibility and Proof of Concept.

Introduction Probe-based confocal laser endomicroscopy (p-CLE) is a method for real-time in vivo visualization of mucosal changes on a cellular level. Due to the size of the endoscopes, it was mainly used in the gastrointestinal tract so far. First investigations on head and neck carcinoma described the oropharyngeal application. The further miniaturization of the laser probe now allows endonasal application and, thus, first experiences with the investigation of endonasal neoplasms. Objectives The aim of the present investigation is to elucidate, based on the morphological criteria validated in the oropharynx, whether these criteria be transferred in a similar way to the endonasal mucosa. Methods We conducted p-CLE (Cellvizio, Paris, France) with intravenous fluorescein staining in endoscopic sinus surgery in a patient with sinonasal inverted papilloma and a histologically confirmed squamous cell carcinoma. We compared the cellular visualization of pathological changes with those of healthy mucosa in the same specimen, and also with our former findings in the oropharynx. Results Endonasal p-CLE proved to be quite feasible in the surgical setting, and the transfer of malignancy criteria in analogy to histological examination could be optically retraced. Furthermore, additional criteria for tissue dignity assessment were obtained. Conclusion Our results suggest that endonasal application of p-CLE represents a valuable extension of the diagnostic repertoire available to date by an additional real-time analysis of the nasal mucosa. This is of particular value in surgically challenging anatomical areas such as the paranasal sinuses. Further investigation and validation will be necessary.

PICaSSO Histologic Remission Index (PHRI) in ulcerative colitis: development of a novel simplified histological score for monitoring mucosal healing and predicting clinical outcomes and its applicability in an artificial intelligence system.

Histological remission is evolving as an important treatment target in UC. We aimed to develop a simple histological index, aligned to endoscopy, correlated with clinical outcomes, and suited to apply to an artificial intelligence (AI) system to evaluate inflammatory activity. METHODS: Using a set of 614 biopsies from 307 patients with UC enrolled into a prospective multicentre study, we developed the Paddington International virtual ChromoendoScopy ScOre (PICaSSO) Histologic Remission Index (PHRI). Agreement with multiple other histological indices and validation for inter-reader reproducibility were assessed. Finally, to implement PHRI into a computer-aided diagnosis system, we trained and tested a novel deep learning strategy based on a CNN architecture to detect neutrophils, calculate PHRI and identify active from quiescent UC using a subset of 138 biopsies. RESULTS: PHRI is strongly correlated with endoscopic scores (Mayo Endoscopic Score and UC Endoscopic Index of Severity and PICaSSO) and with clinical outcomes (hospitalisation, colectomy and initiation or changes in medical therapy due to UC flare-up). A PHRI score of 1 could accurately stratify patients' risk of adverse outcomes (hospitalisation, colectomy and treatment optimisation due to flare-up) within 12 months. Our inter-reader agreement was high (intraclass correlation 0.84). Our preliminary AI algorithm differentiated active from quiescent UC with 78% sensitivity, 91.7% specificity and 86% accuracy. CONCLUSIONS: PHRI is a simple histological index in UC, and it exhibits the highest correlation with endoscopic activity and clinical outcomes. A PHRI-based AI system was accurate in predicting histological remission.

PICaSSO virtual electronic chromendoscopy accurately reflects combined endoscopic and histological assessment for prediction of clinical outcomes in ulcerative colitis.

BACKGROUND AND AIMS: A composite endoscopic-histologic remission is increasingly explored as an important endpoint in ulcerative colitis (UC). We investigated combined endoscopic-histologic remission for predicting clinical outcomes at 12 months compared with endoscopic remission alone using the high definition virtual chromoendoscopy (VCE) Paddington International virtual ChromoendoScopy ScOre (PICaSSO) and histology scores. METHODS: Ulcerative colitis patients, prospectively enrolled from 11 international centres, underwent VCE with targeted biopsies and followed up for 12 months. Endoscopic activity was assessed by Mayo Endoscopic Score (MES), Ulcerative Colitis Endoscopic Index Severity (UCEIS) followed by VCE-PICaSSO. Robarts Histopathological Index|Robarts Histological index≤3 without neutrophils in mucosa, and Nancy Histological index (NHI)≤ 1 were used to define histologic remission. Combined endoscopic-histologic remission was compared with endoscopic remission alone by Cox proportional hazards model and by two- and three-proportion analysis using pre-specified clinical outcomes. RESULTS: 307 patients were recruited and 302 analysed. There was no difference in survival without specified clinical outcomes between PICaSSO defined endoscopic remission alone and endoscopic plus histologic remission in the rectum (HR 0.42, 95%CI 0.16-1.11 and HR 1.03, 95%CI 0.42-2.52 for Robarts Histological index and NHI respectively) at 12 months. There was however a significant survival advantage without specified clinical outcome events for UCEIS combined with histology compared with UCEIS alone (HR 0.30, 95%CI 0.12-0.75, p = 0.02) at 12 months (but not combined with NHI). For MES there was no advantage for predicting specified clinical outcomes at 12 months for endoscopy alone versus endoscopy plus histology, but there were differences in two and three proportion analysis at 6 months. CONCLUSION: Endoscopic remission by VCE-PICaSSO alone was similar to combined endoscopic and histologic remission for predicting specified clinical outcomes at 12 months. Larger studies with specific therapeutic interventions are required to further confirm the findings.

Prospective, double-blind diagnostic multicentre study of confocal laser endomicroscopy for wheat sensitivity in patients with irritable bowel syndrome.

OBJECTIVE: A considerable proportion of patients with irritable bowel syndrome (IBS) may be wheat-sensitive and respond to a gluten-free diet (GFD) although they do not have coeliac disease. However, a diagnostic test for wheat sensitivity (WS) is missing. Our study evaluated the diagnostic accuracy (sensitivity and specificity) of confocal laser endomicroscopy (CLE) for the identification of WS as primary outcome. DESIGN: In this prospective, double-blind diagnostic study 147 non-coeliac patients fulfilling the Rome III criteria for IBS were tested by CLE for duodenal changes after wheat (index test), soy, yeast or milk exposure. Patients with IBS responding to 2 months of GFD were classified as having WS (reference test) using response criteria recommended by regulatory bodies for pharmaceutical trials of patients with IBS. After 2 months, CLE results were unblinded and patients were advised to exclude those food components that had led to a positive CLE reaction. The clinical response was assessed at follow-up after 6 and 12 months. RESULTS: Of 130 patients who completed the study per protocol, 74 (56.9%) responded to GFD and were classified as WS after 2 months, and 38 of these 74 patients were correctly identified by CLE (sensitivity 51.4%; 97.5% CI: 38.7% to 63.9%). A total of 38 of 56 patients without WS were correctly identified by CLE (specificity 67.9%; 97.5% CI: 52.9% to 79.9%). At 6 months follow-up, CLE correctly identified 49 of 59 food-sensitive patients (sensitivity 83.1%; 97.5% CI: 69.9% to 91.3%) but specificity was only 32% (97.5% CI: 15.7% to 54.3%). CONCLUSION: In light of the high proportion of patients with IBS responding to GFD, the diagnostic accuracy of CLE is too low to recommend widespread use of this invasive procedure. TRAIL REGISTRATION NUMBER: This study was registered as clinical trial in the German Registry for Clinical Studies (DRKS00010123).

Unmasking lower gastrointestinal bleeding under administration of norepinephrine.

BACKGROUND: Bleeding in the gastrointestinal tract is common and transarterial embolization enables the clinician to control gastrointestinal bleeding. Contrast extravasation is a prerequisite for successful embolization. Provocative angiography is helpful in the detection of elusive bleeding. AIM: We performed a retrospective analysis of angiographic treatment in patients with lower gastrointestinal hemorrhage and initially negative angiographies, as well as the role of norepinephrine (NE) in unmasking bleeding. METHODS: We analyzed 41 patients with lower gastrointestinal bleeding after angiography who had undergone treatment over a period of 10 years. All patients had a positive shock index and needed intensive care. RESULTS: In three of four patients, angiography disclosed the site of bleeding when NE was used during the procedure for hemodynamic stabilization. CONCLUSION: We suggest that angiography performed after the administration of NE in unstable patients with gastrointestinal bleeding and an initially negative angiography has the potential to unmask bleeding sites for successful embolization. However, this statement must be confirmed in prospective studies.

Colour me blue: chromoendoscopy and advanced detection methods in ulcerative colitis.

INTRODUCTION: Surveillance colonoscopy is recommended in patients with long standing ulcerative colitis or Crohn's colitis. Chromoendoscopy is the main technique for increased detection of colitis-associated dysplasia. However, the recommendation was made on the basis of studies using standard definition colonoscopes. PURPOSE OF REVIEW: This review highlights randomized controlled trials and meta-analysis, which were published between 2018 and 2021 with the focus of conventional chromoendoscopy, virtual chromoendoscopy and high-definition imaging. In addition, studies investigating the value of random biopsies were also evaluated. RECENT FINDINGS: Chromoendoscopy increases the total number of colitis-associated dysplasia even by using high-definition colonoscopes. However, the procedure time is prolonged and there is no significant difference in the diagnostic yield of high definition alone and high definition with chromoendoscopy. Virtual chromoendoscopy seems not to develop a role for surveillance in inflammatory bowel disease (IBD) patients. SUMMARY: High-definition colonoscopy and conventional chromoendoscopy are key techniques for surveillance in IBD.

Endoscopic hemostasis makes the difference: Angiographic treatment in patients with lower gastrointestinal bleeding.

BACKGROUND: The large majority of gastrointestinal bleedings subside on their own or after endoscopic treatment. However, a small number of these may pose a challenge in terms of therapy because the patients develop hemodynamic instability, and endoscopy does not achieve adequate hemostasis. Interventional radiology supplemented with catheter angiography (CA) and transarterial embolization have gained importance in recent times. AIM: To evaluate clinical predictors for angiography in patients with lower gastrointestinal bleeding (LGIB). METHODS: We compared two groups of patients in a retrospective analysis. One group had been treated for more than 10 years with CA for LGIB (n = 41). The control group had undergone non-endoscopic or endoscopic treatment for two years and been registered in a bleeding registry (n = 92). The differences between the two groups were analyzed using decision trees with the goal of defining clear rules for optimal treatment. RESULTS: Patients in the CA group had a higher shock index, a higher Glasgow-Blatchford bleeding score (GBS), lower serum hemoglobin levels, and more rarely achieved hemostasis in primary endoscopy. These patients needed more transfusions, had longer hospital stays, and had to undergo subsequent surgery more frequently (P < 0.001). CONCLUSION: Endoscopic hemostasis proved to be the crucial difference between the two patient groups. Primary endoscopic hemostasis, along with GBS and the number of transfusions, would permit a stratification of risks. After prospective confirmation of the present findings, the use of decision trees would permit the identification of patients at risk for subsequent diagnosis and treatment based on interventional radiology.

Hemostatic powder TC-325 treatment of malignancy-related upper gastrointestinal bleeds: International registry outcomes.

BACKGROUND AND AIM: Upper gastrointestinal tumors account for 5% of upper gastrointestinal bleeds. These patients are challenging to treat due to the diffuse nature of the neoplastic bleeding lesions, high rebleeding rates, and significant transfusion requirements. TC-325 (Cook Medical, North Carolina, USA) is a hemostatic powder for gastrointestinal bleeding. The aim of this study was to examine the outcomes of upper gastrointestinal bleeds secondary to tumors treated with Hemospray therapy. METHODS: Data were prospectively collected on the use of Hemospray from 17 centers. Hemospray was used during emergency endoscopy for upper gastrointestinal bleeds secondary to tumors at the discretion of the endoscopist as a monotherapy, dual therapy with standard hemostatic techniques, or rescue therapy. RESULTS: One hundred and five patients with upper gastrointestinal bleeds secondary to tumors were recruited. The median Blatchford score at baseline was 10 (interquartile range [IQR], 7-12). The median Rockall score was 8 (IQR, 7-9). Immediate hemostasis was achieved in 102/105 (97%) patients, 15% of patients had a 30-day rebleed, 20% of patients died within 30 days (all-cause mortality). There was a significant improvement in transfusion requirements following treatment (P < 0.001) when comparing the number of units transfused 3 weeks before and after treatment. The mean reduction was one unit per patient. CONCLUSIONS: Hemospray achieved high rates of immediate hemostasis, with comparable rebleed rates following treatment of tumor-related upper gastrointestinal bleeds. Hemospray helped in improving transfusion requirements in these patients. This allows for patient stabilization and bridges towards definitive surgery or radiotherapy to treat the underlying tumor.