Clinical consequences of computer-aided colorectal polyp detection.

BACKGROUND AND AIM: Randomised trials show improved polyp detection with computer-aided detection (CADe), mostly of small lesions. However, operator and selection bias may affect CADe's true benefit. Clinical outcomes of increased detection have not yet been fully elucidated. METHODS: In this multicentre trial, CADe combining convolutional and recurrent neural networks was used for polyp detection. Blinded endoscopists were monitored in real time by a second observer with CADe access. CADe detections prompted reinspection. Adenoma detection rates (ADR) and polyp detection rates were measured prestudy and poststudy. Histological assessments were done by independent histopathologists. The primary outcome compared polyp detection between endoscopists and CADe. RESULTS: In 946 patients (51.9% male, mean age 64), a total of 2141 polyps were identified, including 989 adenomas. CADe was not superior to human polyp detection (sensitivity 94.6% vs 96.0%) but outperformed them when restricted to adenomas. Unblinding led to an additional yield of 86 true positive polyp detections (1.1% ADR increase per patient; 73.8% were <5 mm). CADe also increased non-neoplastic polyp detection by an absolute value of 4.9% of the cases (1.8% increase of entire polyp load). Procedure time increased with 6.6±6.5 min (+42.6%). In 22/946 patients, the additional detection of adenomas changed surveillance intervals (2.3%), mostly by increasing the number of small adenomas beyond the cut-off. CONCLUSION: Even if CADe appears to be slightly more sensitive than human endoscopists, the additional gain in ADR was minimal and follow-up intervals rarely changed. Additional inspection of non-neoplastic lesions was increased, adding to the inspection and/or polypectomy workload.

Informed consent for endoscopic procedures: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement.

All endoscopic procedures are invasive and carry risk. Accordingly, all endoscopists should involve the patient in the decision-making process about the most appropriate endoscopic procedure for that individual, in keeping with a patient's right to self-determination and autonomy. Recognition of this has led to detailed guidelines on informed consent for endoscopy in some countries, but in many no such guidance exists; this may lead to variations in care and exposure to risk of litigation. In this document, the European Society of Gastrointestinal Endoscopy (ESGE) sets out a series of statements that cover best practice in informed consent for endoscopy. These statements should be seen as a minimum standard of practice, but practitioners must be aware of and adhere to the law in their own country. 1: Patients should give informed consent for all gastrointestinal endoscopic procedures for which they have capacity to do so. 2: The healthcare professional seeking consent for an endoscopic procedure should ensure that the patient has the capacity to consent to that procedure. 3: For patients who lack capacity, healthcare personnel should at all times try to engage with people close to the patient, such as family, friends, or caregivers, to achieve consensus on the appropriateness of performing the procedure. 4: Where a patient lacks capacity to provide informed consent, the best interest decision should be clearly documented in the medical record. This should include information about the capacity assessment, reason(s) that the decision cannot be delayed for capacity recovery (or if recovery is not expected), who has been consulted, and where relevant the form of authority for the decision. 5: There should be a systematic and transparent disclosure of the expected benefits and harms that may reasonably affect patient choice on whether or not to undergo any diagnostic or interventional endoscopic procedure. Information about possible alternatives, as well as the consequences of doing nothing, should also be provided when relevant. 6: The information provided on the benefit and harms of an endoscopic procedure should be adapted to the procedure and patient-specific risk factors, and the preferences of the patient should be central to the consent process. 7: The consent discussion should be undertaken by an individual who is familiar with the procedure and its risks, and is able to discuss these in the context of the individual patient. 8: Patients should confirm consent to an endoscopic procedure in a private, unrushed, and non-coercive environment. 9: If a patient requests that an endoscopic procedure be discontinued, the procedure should be paused and the patient's capacity for decision making assessed. If a competent patient continues to object to the procedure, or if a conclusive determination of capacity is not feasible, the examination should be terminated as soon as it is safe to do so. 10: Informed consent should be sufficiently detailed to cover all findings that can be reasonably anticipated during an endoscopic examination. The scope of this consent should not be expanded, nor a patient's implicit consent for additional interventions assumed, unless failure to proceed with such interventions would result in immediate and predictable harm to the patient.

Injection of botulinum toxin significantly increases efficiency of fissurectomy in the treatment of chronic anal fissures.

PURPOSE: While acute anal fissures can be treated with topical therapy to reduce sphincter hypertonia (e.g., isosorbide dinitrate, glyceryl trinitrate, diltiazem), chronic fissures may require more invasive instrumental therapy. Currently, the golden standard remains lateral internal sphincterotomy; however, this carries the long-term risk of faecal incontinence. Fissurectomy can be a valuable alternative, but is less efficient because of absence of correction of underlying hypertonia. In this study, we aim to evaluate the additional effect of injection of botulinum toxin during fissurectomy in the treatment of chronic anal fissures. METHODS: A single-centre retrospective analysis of 293 isolated superficial fissurectomies with or without injection of botulinum toxin was performed, with pain relief as primary endpoint. RESULTS: The majority of patients undergoing fissurectomy were women (65%, mean age 45.0 years vs. 35% men, mean age 48.3 years), often because of ventral fissures (30% in women vs. 8% in men). Fissurectomy resulted in resolution of complaints in 81.1%, while additional injection of botulinum toxin resulted in resolution in 90.1% (p < 0.05). Complication rate was identical between the two groups, mainly (flatus) incontinence (4.5% vs 4.9% with botulinum toxin) and post-operative bleeding (1.8% vs 2.5% with botulinum toxin). CONCLUSION: Injection of botulinum toxin significantly increases the efficiency of fissurectomy in the treatment of chronic anal fissures without additional complications.

Analgesic injection of botulinum toxin in anal fissures is efficient and can be performed safely in patients actively receiving chemotherapy.

PURPOSE: Injection of botulinum toxin into the internal anal sphincter is a well-documented intervention to reduce anal hypertonia in the treatment of anal fissures. In patients receiving chemotherapy, painful anal conditions are frequent, secondary to change in bowel habits and reduced immunity. However, injection of botulinum toxin is often not offered due to fear of complications. METHODS: In this retrospective longitudinal observational study, performed in a tertiary hospital setting, we analysed patient characteristics, outcome and complication rates of botulinum toxin injection in patients actively receiving chemotherapy. RESULTS: Twenty-six patients were treated with 20-50 IU botulinum toxin while actively receiving chemotherapy because of intractable pain and hypertonia. The fissure was located dorsally in 69% (n = 18) and ventrally in 19% (n = 5), while in 3 patients (12%), no fissure was documented. The majority of the patients (88%, n = 23) had complete (54%, n = 14) or partial (35%, n = 9) relief of pain. In three patients, additional anal pathology developed in the weeks following botulinum toxin injection: thrombosis of grade IV haemorrhoids, perianal haematoma and an intersphincteric abscess. CONCLUSIONS: Injection of botulinum toxin in the anal sphincters is a safe and effective analgesic option in patients with anal fissure while actively receiving chemotherapy.

COVID-19 and gastrointestinal endoscopy: What should be taken into account?

On March 11, 2020 the World Health Organization declared COVID-19 pandemic, leading to a subsequent impact on the entire world and health care system. Since the causing Severe Acute Respiratory Syndrome Coronavirus 2 houses in the aerodigestive tract, activities in the gastrointestinal outpatient clinic and endoscopy unit should be limited to emergencies only. Health care professionals are faced with the need to perform endoscopic or endoluminal emergency procedures in patients with a confirmed positive or unknown COVID-19 status. With this report, we aim to provide recommendations and practical relevant information for gastroenterologists based on the limited amount of available data and local experience, to guarantee a high-quality patient care and adequate infection prevention in the gastroenterology clinic.

How to select patients for antireflux surgery? The ICARUS guidelines (international consensus regarding preoperative examinations and clinical characteristics assessment to select adult patients for antireflux surgery).

OBJECTIVE: Antireflux surgery can be proposed in patients with GORD, especially when proton pump inhibitor (PPI) use leads to incomplete symptom improvement. However, to date, international consensus guidelines on the clinical criteria and additional technical examinations used in patient selection for antireflux surgery are lacking. We aimed at generating key recommendations in the selection of patients for antireflux surgery. DESIGN: We included 35 international experts (gastroenterologists, surgeons and physiologists) in a Delphi process and developed 37 statements that were revised by the Consensus Group, to start the Delphi process. Three voting rounds followed where each statement was presented with the evidence summary. The panel indicated the degree of agreement for the statement. When 80% of the Consensus Group agreed (A+/A) with a statement, this was defined as consensus. All votes were mutually anonymous. RESULTS: Patients with heartburn with a satisfactory response to PPIs, patients with a hiatal hernia (HH), patients with oesophagitis Los Angeles (LA) grade B or higher and patients with Barrett's oesophagus are good candidates for antireflux surgery. An endoscopy prior to antireflux surgery is mandatory and a barium swallow should be performed in patients with suspicion of a HH or short oesophagus. Oesophageal manometry is mandatory to rule out major motility disorders. Finally, oesophageal pH (±impedance) monitoring of PPI is mandatory to select patients for antireflux surgery, if endoscopy is negative for unequivocal reflux oesophagitis. CONCLUSION: With the ICARUS guidelines, we generated key recommendations for selection of patients for antireflux surgery.

Impact of endoscopy system, high definition, and virtual chromoendoscopy in daily routine colonoscopy: a randomized trial.

BACKGROUND: To improve detection of mucosal lesions during colonoscopy a number of imaging modalities have been suggested, including high definition and virtual chromoendoscopy. Given the theoretical advantage of these new imaging techniques, we aimed to investigate their use for the detection of polyps in patients referred for colonoscopy in a large tertiary hospital. METHODS: Demographic, endoscopic, and histological data from 1855 consecutive patients undergoing colonoscopy were collected prospectively. Patients were randomly assigned to three endoscopy systems (Fujinon, Olympus, or Pentax) in combination with four modalities: conventional white-light colonoscopy (n = 505), high definition white-light colonoscopy (n = 582), virtual chromoendoscopy (n = 285) and high definition virtual chromoendoscopy (n = 483). RESULTS: The mean adenoma detection rate (ADR) was 34.9 %, and the adenoma per colonoscopy rate (APCR) was 2.1. No significant differences were noted between the three endoscopy systems. Moreover, no differences in ADR or APCR were observed between the four imaging modalities. High definition white-light colonoscopy resulted in a significantly higher detection of sessile serrated adenomas (8.2 % vs. 3.8 %; P < 0.01) and adenocarcinomas (2.6 % vs. 0.5 %; P < 0.05) compared with the conventional procedure. CONCLUSIONS: No significant differences in ADR or APCR between different endoscopy systems, high definition, and/or virtual chromoendoscopy could be observed in routine colonoscopies in the general population. High definition endoscopy was associated with a significantly higher detection rate of serrated adenomas and adenocarcinomas.

Advanced endoscopic imaging: European Society of Gastrointestinal Endoscopy (ESGE) Technology Review.

Background and aim: This technical review is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It addresses the utilization of advanced endoscopic imaging in gastrointestinal (GI) endoscopy. Methods: This technical review is based on a systematic literature search to evaluate the evidence supporting the use of advanced endoscopic imaging throughout the GI tract. Technologies considered include narrowed-spectrum endoscopy (narrow band imaging [NBI]; flexible spectral imaging color enhancement [FICE]; i-Scan digital contrast [I-SCAN]), autofluorescence imaging (AFI), and confocal laser endomicroscopy (CLE). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was adopted to define the strength of recommendation and the quality of evidence. Main recommendations:1. We suggest advanced endoscopic imaging technologies improve mucosal visualization and enhance fine structural and microvascular detail. Expert endoscopic diagnosis may be improved by advanced imaging, but as yet in community-based practice no technology has been shown consistently to be diagnostically superior to current practice with high definition white light. (Low quality evidence.) 2. We recommend the use of validated classification systems to support the use of optical diagnosis with advanced endoscopic imaging in the upper and lower GI tracts (strong recommendation, moderate quality evidence). 3. We suggest that training improves performance in the use of advanced endoscopic imaging techniques and that it is a prerequisite for use in clinical practice. A learning curve exists and training alone does not guarantee sustained high performances in clinical practice. (Weak recommendation, low quality evidence.) Conclusion: Advanced endoscopic imaging can improve mucosal visualization and endoscopic diagnosis; however it requires training and the use of validated classification systems.

HNF1B deficiency causes ciliary defects in human cholangiocytes.

Heterozygous deletion or mutation in hepatocyte nuclear factor 1 homeobox B/transcription factor 2 (HNF1B/TCF2) causes renal cyst and diabetes syndrome (OMIM #137920). Mice with homozygous liver-specific deletion of Hnf1ß revealed that a complete lack of this factor leads to ductopenia and bile duct dysplasia, in addition to mild hepatocyte defects. However, little is known about the hepatic consequences of deficient HNF1B function in humans. Three patients with heterozygous HNF1B deficiency were found to have normal bile duct formation on radiology and routine liver pathology. Electron microscopy revealed a paucity or absence of normal primary cilia. Therefore, heterozygous HNF1B deficiency is associated with ciliary anomalies in cholangiocytes, and this may cause cholestasis.

Successful isolation of liver progenitor cells by aldehyde dehydrogenase activity in naïve mice.

UNLABELLED: The role of progenitor cells in liver repair and fibrosis has been extensively described, but their purification remains a challenge, hampering their characterization and use in regenerative medicine. To address this issue, we developed an easy and reproducible liver progenitor cell (LPC) isolation strategy based on aldehyde dehydrogenase (ALDH) activity, a common feature shared by many progenitor cells. We demonstrate that a subset of nonparenchymal mouse liver cells displays high levels of ALDH activity, allowing the isolation of these cells by fluorescence-activated cell sorting. Immunocytochemistry and qPCR analyses on freshly isolated ALDH(+) cells reveal an enrichment in cells expressing liver stem cell markers such as EpCAM, CK19, CD133, and Sox9. In culture, the ALDH(+) population can give rise to functional hepatocyte-like cells as illustrated by albumin and urea secretion and cytochrome P450 activity. ALDH1A1 expression can be detected in canals of Hering and bile duct epithelial cells and is increased on liver injury. Finally, we showed that the isolation and differentiation toward hepatocyte-like cells of LPCs with high ALDH activity is also successfully applicable to human liver samples. CONCLUSION: High ALDH activity is a feature of LPCs that can be taken advantage of to isolate these cells from untreated mouse as well as human liver tissues. This novel protocol is practically relevant, because it provides an easy and nontoxic method to isolate liver stem cells from normal tissue for potential therapeutic purposes.

Human pluripotent stem cell-derived hepatocytes support complete replication of hepatitis C virus.

BACKGROUND & AIMS: Worldwide, about 180 million people are chronically infected with the hepatitis C virus (HCV). Current in vitro culture systems for HCV depend chiefly on human hepatoma cell lines. Although primary human hepatocytes support HCV infection in vitro, and immunodeficient mice repopulated with human hepatocytes support HCV infection in vivo, these models are limited because of shortage of human livers to isolate hepatocytes. Therefore, there is significant interest in the establishment from of a HCV culture system in human stem cell-derived hepatocyte-like cells. METHODS: Human embryonic stem cell (hESC)-derived hepatocytes were infected with HCV in the presence or absence of direct acting antivirals. After inoculation, replication of HCV was analyzed extensively. RESULTS: We demonstrate that hESC-derived hepatocytes can be infected with the HCV JFH1 genotype 2a, resulting in the production of viral RNA in the stem cell progeny. Viral replication is inhibited by a non-nucleoside HCV polymerase-inhibitor (HCV-796), a cyclophilin binding molecule (Debio 025-Alisporivir) and the protease inhibitor VX-950 (Telaprevir). Stem cell-derived hepatocytes produced, for more than 10 days, the HCV core protein as well as virions that were capable of re-infecting hepatoma cells. CONCLUSIONS: Hepatocytes derived from hESC support the complete HCV replication cycle (including the production of infectious virus), and viral replication in these cells is efficiently inhibited by selective inhibitors of HCV replication.

Implementation of the Aldrete score reduces recovery time after non-anesthesiologist-administered procedural sedation in gastrointestinal endoscopy.

Background and study aims Procedural sedation and analgesia (PSA) by trained non-anesthesiologist physicians and/or nurses is often performed during endoscopic procedures. Discharge from the recovery area after monitored observation is frequently based on fixed time parameters or subjective clinical assessment. In this study, the effect of implementation of the Aldrete score on recovery time after procedural sedation was analyzed in a real-life setting. Patients and methods A prospective observational study of patients undergoing procedural sedation and analgesia during gastroscopy, colonoscopy or endoscopic ultrasound was performed. All procedures were randomly included to represent a real-life situation with different endoscopists, recovery nurses, endoscopy systems and indications. After a first observation period, all endoscopy nurses were trained to implement the Aldrete score when discharging patients, followed by a second observation period. Results During the first observation period, the average time spent in the recovery area was 59 ±â€Š22 minutes after procedural sedation. After implementation of the Aldrete score, the recovery time decreased significantly to 47 ±â€Š25 minutes ( P  < 0.01) with identical doses of procedural sedation and analgesia. The decrease in time was between 19 % and 35 % for the different endoscopic procedures. Conclusions Implementation of the Aldrete score after procedural sedation and analgesia significantly reduces the time spent in the recovery area. The score can be used to safely implement a discharge policy that provides more efficient and standardized management for an endoscopy service.

Directed differentiation of murine-induced pluripotent stem cells to functional hepatocyte-like cells.

BACKGROUND & AIMS: Induced pluripotent stem (iPS) cells exert phenotypic and functional characteristics of embryonic stem cells even though the gene expression pattern is not completely identical. Therefore, it is important to develop procedures which are specifically oriented to induce iPS cell differentiation. METHODS: In this study, we describe the differentiation of mouse iPS cells to hepatocyte-like cells, following a directed differentiation procedure that mimics embryonic and fetal liver development. The sequential differentiation was monitored by real-time PCR, immunostaining, and functional assays. RESULTS: By sequential stimulation with cytokines known to play a role in liver development, iPS cells were specified to primitive streak/mesendoderm/definitive endoderm. They were then differentiated into two types of cells: those with hepatoblast features and those with hepatocyte characteristics. Differentiated hepatocyte-like cells showed functional properties of hepatocytes, such as albumin secretion, glycogen storage, urea production, and inducible cytochrome activity. Aside from hepatocyte-like cells, mesodermal cells displaying some characteristics of liver sinusoidal endothelium and stellate cells were also detected. CONCLUSIONS: These data demonstrate that a protocol, modeled on embryonic liver development, can induce hepatic differentiation of mouse iPS cells, generating a population of cells with mature hepatic phenotype.

Gastrointestinal mucosal damage in patients with COVID-19 undergoing endoscopy: an international multicentre study.

BACKGROUND: Although evidence suggests frequent gastrointestinal (GI) involvement during coronavirus disease 2019 (COVID-19), endoscopic findings are scarcely reported. AIMS: We aimed at registering endoscopic abnormalities and potentially associated risk factors among patients with COVID-19. METHODS: All consecutive patients with COVID-19 undergoing endoscopy in 16 institutions from high-prevalence regions were enrolled. Mann-Whitney U, χ2 or Fisher's exact test were used to compare patients with major abnormalities to those with negative procedures, and multivariate logistic regression to identify independent predictors. RESULTS: Between February and May 2020, during the first pandemic outbreak with severely restricted endoscopy activity, 114 endoscopies on 106 patients with COVID-19 were performed in 16 institutions (men=70.8%, median age=68 (58-74); 33% admitted in intensive care unit; 44.4% reporting GI symptoms). 66.7% endoscopies were urgent, mainly for overt GI bleeding. 52 (45.6%) patients had major abnormalities, whereas 13 bled from previous conditions. The most prevalent upper GI abnormalities were ulcers (25.3%), erosive/ulcerative gastro-duodenopathy (16.1%) and petechial/haemorrhagic gastropathy (9.2%). Among lower GI endoscopies, 33.3% showed an ischaemic-like colitis.Receiver operating curve analysis identified D-dimers >1850 ng/mL as predicting major abnormalities. Only D-dimers >1850 ng/mL (OR=12.12 (1.69-86.87)) and presence of GI symptoms (OR=6.17 (1.13-33.67)) were independently associated with major abnormalities at multivariate analysis. CONCLUSION: In this highly selected cohort of hospitalised patients with COVID-19 requiring endoscopy, almost half showed acute mucosal injuries and more than one-third of lower GI endoscopies had features of ischaemic colitis. Among the hospitalisation-related and patient-related variables evaluated in this study, D-dimers above 1850 ng/mL was the most useful at predicting major mucosal abnormalities at endoscopy. TRIAL REGISTRATION NUMBER: ClinicalTrial.gov (ID: NCT04318366).

A survey on the impact of the COVID-19 pandemic on motility and functional investigations in Europe and considerations for recommencing activities in the early recovery phase.

BACKGROUND: The COVID-19 pandemic, declared by WHO on March 13, 2020, had a major global impact on the healthcare system and services. In the acute phase, the presence of the SARS-CoV-2 virus in the aerodigestive tract limited activities in the gastroenterology clinic and procedures to emergencies only. Motility and function testing was interrupted and as we enter the recovery phase, restarting these procedures requires a safety-focused approach with adequate infection prevention for patients and healthcare professionals. METHODS: We summarized knowledge on the presence of the SARS-CoV-2 virus in the aerodigestive tract and the risk of spread with motility and functional testing. We surveyed 39 European centers documenting how the pandemic affected activities and which measures they are considering for restarting these measurements. We propose recommendations based on current knowledge as applied in our center. RESULTS: Positioning of catheters for gastrointestinal motility tests carries a concern for aerosol-borne infection of healthcare workers. The risk is low with breath tests. The surveyed centers stopped almost all motility and function tests from the second half of March. The speed of restarting and the safety measures taken varied highly. CONCLUSIONS AND INFERENCES: Based on these findings, we provided recommendations and practical relevant information for motility and function test procedures in the COVID-19 pandemic era, to guarantee a high-quality patient care with adequate infection prevention.