Predictive findings for Helicobacter pylori-uninfected, -infected and -eradicated gastric mucosa: Validation study

Development and application of an artificial intelligence-assisted endoscopy system for diagnosis of Helicobacter pylori infection: a multicenter randomized controlled study

BACKGROUND

The early diagnosis and treatment of Heliobacter pylori (H.pylori) gastrointestinal infection provide significant benefits to patients. We constructed a convolutional neural network (CNN) model based on an endoscopic system to diagnose H. pylori infection, and then examined the potential benefit of this model to endoscopists in their diagnosis of H. pylori infection.

MATERIALS AND METHODS

A CNN neural network system for endoscopic diagnosis of H.pylori infection was established by collecting 7377 endoscopic images from 639 patients. The accuracy, sensitivity, and specificity were determined. Then, a randomized controlled study was used to compare the accuracy of diagnosis of H. pylori infection by endoscopists who were assisted or unassisted by this CNN model.

RESULTS

The deep CNN model for diagnosis of H. pylori infection had an accuracy of 89.6%, a sensitivity of 90.9%, and a specificity of 88.9%. Relative to the group of endoscopists unassisted by AI, the AI-assisted group had better accuracy (92.8% [194/209; 95%CI: 89.3%, 96.4%] vs. 75.6% [158/209; 95%CI: 69.7%, 81.5%]), sensitivity (91.8% [67/73; 95%CI: 85.3%, 98.2%] vs. 78.6% [44/56; 95%CI: 67.5%, 89.7%]), and specificity (93.4% [127/136; 95%CI: 89.2%, 97.6%] vs. 74.5% [114/153; 95%CI: 67.5%, 81.5%]). All of these differences were statistically significant (P < 0.05).

CONCLUSION

Our AI-assisted system for diagnosis of H. pylori infection has significant ability for diagnostic, and can improve the accuracy of endoscopists in gastroscopic diagnosis.

TRIAL REGISTRATION

This study was approved by the Ethics Committee of Daping Hospital (10/07/2020) (No.89,2020) and was registered with the Chinese Clinical Trial Registration Center (02/09/2020)   ( www.chictr.org.cn ; registration number: ChiCTR2000037801).

Prevalence of Gastric Epithelial Tumors in Helicobacter pylori-uninfected Individuals Undergoing a Medical Checkup

Objective This study investigated the prevalence of gastric epithelial tumor in Helicobacter pylori-uninfected subjects who underwent esophagogastroduodenoscopy (EGD) as part of an annual checkup. Methods A total of 20,540 EGD examinations of H. pylori-uninfected individuals (12,917 men, 7,623 women; mean age 51.5±9.2 years old) were performed between April 2016 and March 2023. The prevalence of gastric epithelial tumor discovery and the size and location of each lesion type were analyzed. Results According to 20,540 examinations, 61 gastric epithelial tumors were endoscopically and histologically diagnosed in 58 of the subjects, with a prevalence rate of 0.28%. These tumors included signet-ring carcinoma (n=10, 0.05%), gastric adenocarcinoma of fundic-gland type (n=10, 0.05%), intestinal-type well-differentiated adenocarcinoma (n=2, 0.01%), and raspberry-type gastric foveolar tumors (n=36, 0.18%). One subject had two intestinal-type well-differentiated adenocarcinomas, and two each had two raspberry-type gastric foveolar tumors. The mean sizes of the signet-ring carcinomas, gastric adenocarcinoma of fundic-gland type, intestinal-type well-differentiated adenocarcinomas, and raspberry-type gastric foveolar tumors were 6.4, 4.7, 5.0, and 3.4 mm, respectively. Each lesion was located at a specific site in the stomach characteristic of its type. Conclusion In the present H. pylori-uninfected subjects, the prevalence of gastric epithelial tumors found on an EGD examination was 0.28%. Endoscopic examination should be performed in H. pylori-uninfected individuals to detect such tumors in characteristic locations.

The value of LCI-based modified Kyoto classification risk scoring system in predicting the risk of early gastric cancer

OBJECTIVE

To study and compare the value of the Kyoto classification risk scoring system and the modified Kyoto classification risk scoring system based on linked color imaging (LCI) in predicting the risk of early gastric cancer.

METHODS

One hundred and fifty patients with pathologically confirmed non-cardia early gastric cancer by endoscopic LCI and 150 non-gastric cancer patients matched for age and gender were included. Basic patient data and whole gastric endoscopic images under LCI were collected, and the images were scored according to the LCI-based Kyoto classification risk scoring system and the LCI-based modified Kyoto classification risk scoring system.

RESULTS

Compared with the LCI-based Kyoto classification risk scoring system, the LCI-based modified Kyoto classification risk scoring system had a higher AUC for predicting the risk of early gastric cancer (0.723 vs. 0.784, p = 0.023), with a score of ≥3 being the best cutoff value for predicting the risk of early gastric cancer (sensitivity 61.33%, specificity 86.00%), and scores of 3 to 5 were significantly associated with early gastric carcinogenesis significantly (OR = 9.032, 95% CI: 4.995-16.330, p < 0.001).

CONCLUSIONS

Compared with the LCI-based Kyoto classification risk scoring system, the LCI-based Kyoto modified classification risk scoring system has a better value for predicting the risk of early gastric cancer, and the score of 3 to 5 is a high-risk factor for the risk of early gastric cancer development, which is more strongly correlated with the risk of early gastric cancer.

Diagnostic performance of linked color imaging for gastric cancer by Helicobacter pylori infection status: A subanalysis of the large-scale, multicenter randomized controlled trial LCI-FIND

BACKGROUND

Linked color imaging (LCI) is a new image enhancement technology that facilitates the recognition of subtle differences in mucosal color. In the large-scale, multicenter randomized controlled trial LCI-FIND, LCI demonstrated good diagnostic performance for the detection of tumor lesions in the upper gastrointestinal tract. The aim of the present study was to exploratively evaluate the diagnostic performance of LCI according to H. pylori infection status as a subanalysis of LCI-FIND trial.

METHODS

The patients were randomly allocated to receive white light imaging (WLI) first, followed by LCI (WLI group), or vice versa (LCI group), and the two groups were compared for the detection of tumors. Data from this trial were analyzed by the presence/absence of H. pylori infection and further analyzed by successful or unsuccessful eradication in the H. pylori infection group.

RESULTS

The 752 patients in the WLI group and 750 patients in the LCI group who had participated in the LCI-FIND trial were included. In the successful eradication group, more gastric lesions were detected by primary mode in the LCI group than in the WLI group, indicating that more lesions were missed by WLI. Fisher's exact probability test for the comparison of the WLI and LCI groups yielded a p-value of 0.0068, with missed gastric lesions being detected 0.136 times (95% confidence interval: 0.020-0.923), significantly less with LCI than with WLI.

CONCLUSION

The current study suggests that LCI should be used for gastric cancer screening, particularly in patients with successful H. pylori eradication.

Factors Associated with Overlap between Functional Dyspepsia and Nonerosive Reflux Disease in Endoscopy-based Helicobacter pylori-uninfected Japanese Health Checkup Participants: A Prospective, Multicenter Cross-sectional Study

Objective We assessed the factors associated with overlap between functional dyspepsia (FD) and nonerosive reflux disease (NERD) in endoscopy-based Helicobacter pylori-uninfected Japanese health checkup participants. Methods We utilized baseline data from 3,085 individuals who underwent upper endoscopy for health screening in a prospective, multicenter cohort study. The participants were asked to complete a questionnaire detailing their upper abdominal symptoms and lifestyle. Anxiety was assessed using the State-Trait Anxiety Inventory (STAI) score. FD, postprandial distress syndrome (PDS), and epigastric pain syndrome (EPS) were defined according to the Rome III criteria. NERD was defined as heartburn or regurgitation ≥1 day/week without erosive esophagitis. Results Of the 3,085 participants, 73 (2.4%), 97 (3.1%), and 84 (2.7%) had FD alone, NERD alone, and FD-NERD overlap, respectively. Factors associated with FD-NERD-overlap participants compared with participants with neither FD nor NERD were women [odds ratio (OR): 2.08, 95% confidence interval (CI): 1.24-3.52], body mass index (BMI) <18.5 (OR: 2.87, 95% CI: 1.56-5.07), alcohol consumption ≥20 g/day (OR: 1.85, 95% CI: 1.06-3.15), and a high STAI score (OR: 2.53, 95% CI: 1.62-4.00). Increasing age (OR: 1.06, 95% CI: 1.01-1.11) and EPS symptoms [pure EPS (OR: 3.67, 95% CI: 1.65-8.51) and PDS-EPS overlap (OR: 11.6, 95% CI: 4.09-37.2)] were associated with FD-NERD overlap vs. FD alone. Women (OR: 3.17, 95% CI: 1.47-7.04), BMI <18.5 (OR: 3.03, 95% CI: 1.04-9.90), and acid reflux symptoms ≥2 days a week (OR: 3.57, 95% CI: 1.83-7.14) were associated with FD-NERD overlap vs. NERD alone. Conclusion Understanding the clinical features of overlap between FD and NERD will lead to better management.

Clinical usefulness of linked color imaging in identifying Helicobacter pylori infection: A systematic review and meta-analysis

BACKGROUND

Accurate diagnosis of Helicobacter pylori (H. pylori) infection status is a crucial premise for eradication therapy, as well as evaluation of risk for gastric cancer. Recent progress on imaging enhancement endoscopy (IEE) made it possible to not only detect precancerous lesions and early gastrointestinal cancers but also to predict H. pylori infection in real time. As a novel IEE modality, linked color imaging (LCI) has exhibited its value on diagnosis of lesions of gastric mucosa through emphasizing minor differences of color tone.

AIM

To compare the efficacy of LCI for H. pylori active infection vs conventional white light imaging (WLI).

METHODS

PubMed, Embase, Embase and Cochrane Library were searched up to the end of April 11, 2022. The random-effects model was adopted to calculate the diagnostic efficacy of LCI and WLI. The calculation of sensitivity, specificity, and likelihood ratios were performed; symmetric receiver operator characteristic (SROC) curves and the areas under the SROC curves were computed. Quality of the included studies was chosen to assess using the quality assessment of diagnostic accuracy studies-2 tool.

RESULTS

Seven original studies were included in this study. The pooled sensitivity, specificity, positive likelihood rate, and negative likelihood rate of LCI for the diagnosis of H. pylori infection of gastric mucosa were 0.85 [95% confidence interval (CI): 0.76-0.92], 0.82 (95%CI: 0.78-0.85), 4.71 (95%CI: 3.7-5.9), and 0.18 (95%CI: 0.10-0.31) respectively, with diagnostic odds ratio = 26 (95%CI: 13-52), SROC = 0.87 (95%CI: 0.84-0.90), which showed superiority of diagnostic efficacy compared to WLI.

CONCLUSION

Our results showed LCI can improve efficacy of diagnosis on H. pylori infection, which represents a useful endoscopic evaluation modality for clinical practice.

Characteristic analysis of early gastric cancer after Helicobacter pylori eradication: a multicenter retrospective propensity score-matched study

BACKGROUND

Helicobacter pylori (H. pylori) is recognized as a type I carcinogen in gastric cancer (GC). However, GC still occurs after H. pylori eradication, and its diagnosis is more complicated. This study aimed to summarize the characteristics of early GC (EGC) after H. pylori eradication to help accurately identify EGC and avoid missed diagnosis and misdiagnosis.

METHODS

A total of 81 patients of EGC after H. pylori eradication (Hp-eradicated group), resected by endoscopic submucosal dissection (ESD), and 105 cases of H. pylori infection-related EGC (control group) were assessed. After propensity-score matching, the clinical characteristics, endoscopic manifestations, and histopathological features of the 62 matched patients in each group were analyzed. We also conducted specific analyses in combination with endoscopic and histopathological images.

RESULTS

There were more patients in the Hp-eradicated group who received proton pump inhibitor (PPI) for >1 year compared to the control group (p < 0.001). More patients at OLGA stages I-II before the diagnosis of EGC were in the control group (p = 0.045), especially at stage II. The mucosa in the Hp-eradicated group showed more moderate-to-severe atrophy (p = 0.047), map-like redness (p < 0.001) and mild activity (p < 0.001). The predominant histopathological types differed between the two groups (p < 0.001), and the majority of cases in the Hp-eradicated group were high-grade intraepithelial neoplasia (HGIN). Ki-67 expression was lower in the Hp-eradicated group (p = 0.025). But different eradication intervals of H. pylori have little effect on the characteristics of EGC. Furthermore, PPI uses for >1 year (p = 0.005), mucosal map-like redness (p < 0.001), moderate mucosal atrophy (p = 0.017), and mild activity of gastric mucosa (p = 0.005) were independent characteristics of EGC after H. pylori eradication.

CONCLUSION

Our multicenter study revealed that EGC after H. pylori eradication was characterized by long-term PPI use, moderate mucosal atrophy, mucosal map-like redness, the mild activity of gastric mucosa, a higher proportion of HGIN cases, and lower levels of Ki-67.

Diagnostic usefulness of deep learning methods for Helicobacter pylori infection using esophagogastroduodenoscopy images

Background and Aims

We aimed to assess the diagnostic potential of deep convolutional neural networks (DCNNs) for detecting Helicobacter pylori infection in patients who underwent esophagogastroduodenoscopy and Campylobacter-like organism tests.

Methods

We categorized a total of 13,071 images of various gastric sub-areas and employed five pretrained DCNN architectures: ResNet-101, Xception, Inception-v3, InceptionResnet-v2, and DenseNet-201. Additionally, we created an ensemble model by combining the output probabilities of the best models. We used images of different sub-areas of the stomach for training and evaluated the performance of our models. The diagnostic metrics assessed included area under the curve (AUC), specificity, accuracy, positive predictive value, and negative predictive value.

Results

When training included images from all sub-areas of the stomach, our ensemble model demonstrated the highest AUC (0.867), with specificity at 78.44%, accuracy at 80.28%, positive predictive value at 82.66%, and negative predictive value at 77.37%. Significant differences were observed in AUC between the ensemble model and the individual DCNN models. When training utilized images from each sub-area separately, the AUC values for the antrum, cardia and fundus, lower body greater curvature and lesser curvature, and upper body greater curvature and lesser curvature regions were 0.842, 0.826, 0.718, and 0.858, respectively, when the ensemble model was used.

Conclusions

Our study demonstrates that the DCNN model, designed for automated image analysis, holds promise for the evaluation and diagnosis of Helicobacter pylori infection.

Prevalence of Raspberry-type Gastric Foveolar-type Tumor in Individuals Undergoing Medical Checkups

Objective This study was performed to clarify the prevalence of raspberry-type gastric foveolar-type tumors, along with the time-course changes in the size and clinical course. Methods The subjects were 10,663 consecutive patients who underwent a medical checkup between April 2016 and March 2022, including an esophagogastroduodenoscopy (EGD) examination and determination of Helicobacter pylori infection status (uninfected, positive, post-eradication). The presence of characteristic reddish polypoid lesions in the stomach was investigated, and a diagnosis of raspberry-type gastric foveolar-type tumor was made based on histological findings. Results Thirty-eight cases had gastric polyps with a raspberry-like appearance on endoscopy, with 29 lesions in 28 cases endoscopically and histologically diagnosed as a raspberry-type gastric foveolar-type tumor. All of the affected subjects were determined to be H. pylori-uninfected. The prevalence of this type of lesion in all subjects was 0.26%, while that in the 6,635 H. pylori-uninfected subjects was 0.42%. An older age and the presence of a fundic gland polyp were found to be significant risk factors associated with the occurrence of the tumor. The mean size was 3.8±1.9 (range: 2-10) mm, and the location was in a fundic gland area in all affected subjects. Furthermore, examinations of previous EGD images revealed that two-thirds of the lesions had not changed in size, while follow-up EGD findings showed that lesions ≤5 mm in size had disappeared after a biopsy procedure. Conclusion The prevalence of raspberry-type gastric foveolar-type tumors was 0.42% in H. pylori-uninfected subjects. More than half of the lesions were too small to be removed by an endoscopic biopsy.

A novel endoscopic finding of a scratch sign is useful for evaluating the Helicobacter pylori infection status

Objectives

During esophagogastroduodenoscopy, a red linear scrape-like appearance with white deposits sometimes appears on the gastric mucosa at the lower greater curvature of the gastric body, a finding we named the "scratch sign." We aimed to clarify the clinical significance of this new endoscopic finding in the endoscopic evaluation of the Helicobacter pylori infection status.

Methods

Among patients who underwent esophagogastroduodenoscopy at our hospital between October 2016 and June 2017, 437 patients were included in the study. We first examined the overall scratch sign positivity rate, and then this was compared according to the H. pylori infection status. Subsequently, other variables were compared and examined between the positive and negative scratch sign groups.

Results

Overall, 437 patients were included in the analysis. The scratch sign was observed in 1.4% of 71 patients with current infections, 26.9% of 290 patients with past infections, and 31.6% of 76 uninfected patients. In the multivariate analysis, H. pylori-negative, severe gastric mucosal atrophy, and acid secretion depressant were independent factors that significantly affected the appearance of the scratch sign.

Conclusions

A novel endoscopic finding, the scratch sign, was found to be a good endoscopic predictor of H. pylori-negative gastric mucosa. Furthermore, combined with atrophic changes and xanthomas that persisted after eradication, these findings were found to be useful in accurately diagnosing H. pylori past-infected gastric mucosa endoscopically.

Magnetic controlled capsule endoscope (MCCE)'s diagnostic performance for H. pylori infection status based on the Kyoto classification of gastritis

BACKGROUND

Previous studies have shown that the Kyoto classification of gastritis can accurately predict H. pylori infection status on conventional gastroscopy. The aim of this study was to test whether the Kyoto classification of gastritis applies well to magnetic controlled capsule endoscopy (MCCE).

METHODS

We consecutively recruited 227 participants who underwent both MCCE and urea breath tests (UBTs). Two physicians who were blinded to the UBT results independently made the diagnosis of H. pylori infection status according to 10 findings listed in the Kyoto classification of gastritis after reviewing MCCE images. We also developed 2 predictive models to assess H. pylori infection status by combining these 10 findings.

RESULTS

The MCCE's overall diagnostic accuracy for H. pylori infection status was 80.2%. The sensitivity, specificity and diagnostic odds ratio (DOR) for current infection were 89.4%, 90.1% and 77.1, respectively. Major specific findings were mucosal swelling and spotty redness for current infection, regular arrangement of collecting venules (RAC), streak redness, fundic gland polyp (FGP) for noninfection, and map-like redness for past-infection. In the two prediction models, the area under the curve (AUC) values for predicting noninfection and current infection were 84.7 and 84.9, respectively.

CONCLUSIONS

The Kyoto classification of gastritis applied well to MCCE. H. pylori infection status could be accurately assessed on MCCE according to the Kyoto classification of gastritis.

Degree of Gastric Mucosal Atrophy Correlated Well with Gastric Cancer Occurrence in Patients with Helicobacter pylori-eradicated Status

Objective This study was performed to clarify the association of the degree of gastric mucosal atrophy (GMA) with the occurrence of gastric cancer in patients with Helicobacter pylori-eradicated status. Subjects and Methods The subjects were 3,058 patients (2,035 men, 1,023 women; mean age 57.9 ± 9.5 years old) with H. pylori eradication who underwent esophago-gastroduodenal endoscopy examinations as part of medical checkups conducted between April 2013 and March 2022. The gender, age at eradication, time since eradication, usage of anti-secretory drugs, degree of endoscopic GMA, and FGP prevalence were compared between subjects with and without gastric cancer occurrence. Results Gastric cancer was newly detected in 26 subjects (0.85%) during the study period, with an older age at H. pylori eradication and severe grade of endoscopic GMA being significant risk factors for its occurrence. The gender, smoking history, and usage of anti-secretory drugs were not significantly different between subjects with and without gastric cancer occurrence. A Cox regression analysis showed that an older age at eradication and the degree of GMA were risk factors significantly related to occurrence. Furthermore, the degree of GMA was inversely correlated with FGP development, and gastric cancer was not detected in 467 subjects with FGP prevalence. Conclusion An older age at the time of H. pylori eradication and the degree of GMA are significant risk factors for gastric cancer occurrence in H. pylori-eradicated patients. The FGP prevalence in subjects with H. pylori eradication was inversely associated with GMA, suggesting it was negatively related with gastric cancer occurrence.

Endoscopic Findings and Treatment of Gastric Neoplasms in Familial Adenomatous Polyposis

PURPOSE

Gastric neoplasia is a common manifestation of familial adenomatous polyposis (FAP). This study aimed to elucidate the clinical characteristics, endoscopic features including fundic gland polyposis (FGPsis), and treatment outcomes of gastric neoplasms (GNs) in patients with FAP.

MATERIALS AND METHODS

A total of 35 patients diagnosed with FAP, including nine patients from four pedigrees who underwent esophagogastroduodenoscopy (EGD), were investigated regarding patient characteristics, GN morphology, and treatment outcomes.

RESULTS

Twenty-one patients (60.0%) had 38 GNs; 33 (86.8%) and 5 (13.2%) were histologically diagnosed with adenocarcinoma and adenoma, respectively. There were no specific patient characteristics related to GNs. Nodule-type GNs were more prevalent in patients with FGP than without (52.2% vs. 0.0%, P=0.002) in the upper body of the stomach. Conversely, depressed-type GNs were fewer in patients with FGPsis than in those without (13.0% vs. 73.3%, P<0.001). Slightly elevated-type GNs were observed in both groups (34.8% vs. 20.0%, P=0.538). Even within pedigrees, the background gastric mucosa and types of GNs varied. In total, 24 GNs were treated with endoscopic submucosal dissection (ESD) and eight with endoscopic mucosal resection (EMR). EMR was selected for GNs with FGPsis because of the technical difficulty of ESD, resulting in a lower en bloc resection rate (62.5% vs. 100%, P=0.014).

CONCLUSIONS

Our study indicates the necessity of routine EGD surveillance in patients diagnosed with FAP. Notably, the morphology and location of GNs differed between patients with and without FGPsis. Endoscopic treatment and outcomes require more attention in cases of FGPsis.

Risk factors for early gastric cancer: focus on Helicobacter pylori gastritis

Background: Gastric cancer is a global health problem, and the incidence and geographical distribution of different types of gastric cancer varies. Particularly, noncardiac gastric cancer is more prevalent in East Asia, Central and Eastern Europe, Latin America, and Africa. Infection with Helicobacter pylori, which was discovered in 1982, is a common cause of chronic gastritis, and the association between H. pylori infection and gastric adenocarcinoma is well established.Current Concepts: Gastric cancer is histologically divided into 2 types: intestinal and diffuse. H. pylori infection is considered as the main risk factor for the development of both types of gastric tumors. The most documented course of development of stomach cancer is following cellular metaplasia due to chronic inflammation, damage, and repair. Various molecular alterations caused by H. pylori are identified not only in gastric cancer but also in precancerous lesions. Recently, many studies have attempted to diagnose H. pylori gastritis and precancerous lesions using endoscopy.Discussion and Conclusion: Recent studies have shown that eradication therapy stabilizes or reduces the risk of developing gastric cancer. Therefore, the diagnosis and understanding of gastritis and precancerous lesions caused by H. pylori are the first step in the prevention of gastric cancer.

Prognosis of Seronegative Subjects with a Helicobacter pylori-infected Spouse

Background/Aims: Helicobacter pylori (H. pylori) can disseminate between couples. The present study compared the findings of gastric cancer screening between seronegative subjects according to the presence of an infected spouse.Materials and Methods: Follow-up data of seronegative subjects were analyzed among married couples who underwent gastric cancer screening via gastroscopy, serum pepsinogen, and anti-H. pylori IgG assays between January 2010 and May 2016. New detection rates of H. pylori infection and gastric neoplasm at the follow-up screening were compared between seronegative subjects according to the H. pylori-infected status of spouse.Results: Among 246 seronegative subjects with an H. pylori-infected spouse, 92 underwent follow-up tests (case group). Among 278 seronegative subjects with seronegative spouse, 94 underwent follow-up tests (control group). The past infection rate was higher in the case group than in the control group (52/92 vs. 34/94; P=0.005). New H. pylori infection was diagnosed in three of the 92 cases and two of the 94 controls (3.2% vs. 2.1%; P=0.681). During the mean follow-up of 67.9±36.0 months, three adenocarcinomas and two adenomas (5/184) were newly detected among the cases and their spouses, whereas none (0/188) were detected among the controls and their spouses (2.7% vs. 0%; P=0.029).Conclusions: Gastric neoplasm occurred more frequently in couples with an H. pylori-infected spouse. Because the past infection rate is higher among seronegative subjects with an infected spouse, gastric cancer screening is recommended in both partners when the spouse is infected.

Preventive and inhibitive effects of Yiwei Xiaoyu granules on the development and progression of spasmolytic polypeptide-expressing metaplasia lesions

BACKGROUND

Spasmolytic polypeptide-expressing metaplasia (SPEM) is a potential preneoplastic lesion.

AIM

To elucidate the microRNA (miR)-7-mediated preventive and inhibitive effects of Yiwei Xiaoyu granules (YWXY) in SPEM lesions.

METHODS

Gastric mucosa biopsies were collected from chronic atrophic gastritis patients and healthy people with signed informed consent. YWXY was administered to the mice with induced SPEM by tamoxifen, and the gastric mucosa was harvested on the tenth day of the experiment. Then immunohistochemistry and immunofluorescence were performed to validate the SPEM, lesions and the potential mechanism was investigated. RNA transcripts were detected with reverse transcription-quantitative polymerase chain reaction.

RESULTS

The expression of miR-7 was downregulated in the SPEM lesions, and expression of trefoil factor 2 (TFF2) and clusterin was high in the human gastric mucosa. In vivo experiments showed that YWXY could inhibit the cell proliferation in the tamoxifen-induced SPEM lesions by regulating Ki67. Simultaneously, YWXY could restore the expression of miR-7 by regulating TFF2 by detection with immunofluorescence but not with reverse transcription-quantitative polymerase chain reaction, indicating its potential mechanism of targeting miR-7 by mediating TFF2. The expression of vascular endothelial growth factor-β and gastric intrinsic factor was restored within 3 d of YWXY administration for the SPEM lesions, speculating that the possible mechanism of YWXY is to inhibit the development and progression of SPEM by regulating vascular endothelial growth factor-β and gastric intrinsic factor.

CONCLUSION

miR-7 downregulation is an early event in SPEM through regulation of TFF2 in human gastric mucosa. YWXY is able to inhibit the cell proliferation and restore the expression of miR-7 by mediating TFF2 in the SPEM mouse model.

Helicobacter pylori eradication: Exploring its impacts on the gastric mucosa

Helicobacter pylori (H. pylori) infects approximately 50% of all humans globally. Persistent H. pylori infection causes multiple gastric and extragastric diseases, indicating the importance of early diagnosis and timely treatment. H. pylori eradication produces dramatic changes in the gastric mucosa, resulting in restored function. Consequently, to better understand the importance of H. pylori eradication and clarify the subsequent recovery of gastric mucosal functions after eradication, we summarize histological, endoscopic, and gastric microbiota changes to assess the therapeutic effects on the gastric mucosa.

Assessment of Helicobacter pylori status by examination of gastric mucosal patterns: diagnostic accuracy of white-light endoscopy and narrow-band imaging

Objectives

Helicobacter pylori infection is a common cause of chronic gastritis worldwide and an established risk factor for developing gastric malignancy. The endoscopic appearances predicting H. pylori status are an ongoing area of research, as are their diagnostic accuracies. This study aimed to establish the diagnostic accuracy of several mucosal features predictive of H. pylori negative status and formulate a simple prediction model for use at the time of endoscopy.

Design

Patients undergoing high-definition upper gastrointestinal (GI) endoscopy without magnification were recruited prospectively. During the endoscopy, the presence or absence of specific endoscopic findings was noted. Sydney protocol biopsies were used as the diagnostic reference standard, and urease test if taken. The results informed a logistic regression model used to produce a simple diagnostic approach. This model was subsequently validated using a further cohort of 30 patients.

Results

153 patients were recruited and completed the study protocol. The prevalence of active H. pylori infection was 18.3% (28/153). The overall diagnostic accuracy of the simple prediction model was 80.0%, and 100% of patients with active H. pylori infection were correctly classified. The presence of regular arrangement of collecting venules (RAC) showed a positive predictive value for H. pylori naïve status of 90.7%, rising to 93.6% for patients under the age of 60.

Conclusion

A simple endoscopic model may be accurate for predicting H. pylori status of a patient, and the need for biopsy-based tests. The presence of RAC in the stomach is an accurate predictor of H. pylori negative status, particularly in patients under the age of 60.

Trial registration number

The study was registered with ClinicalTrials.gov, No. NCT02385045.

Diagnosis of Helicobacter pylori Infection and Recent Advances

BACKGROUND

Helicobacter pylori (H. pylori) infects approximately 50% of the world population. Its infection is associated with gastropathies, extra-gastric digestive diseases, and diseases of other systems. There is a canonical process from acute-on-chronic inflammation, chronic atrophic gastritis (CAG), intestinal metaplasia (IM), dysplasia, and intraepithelial neoplasia, eventually to gastric cancer (GC). H. pylori eradication abolishes the inflammatory response and early treatment prevents the progression to preneoplastic lesions.

METHODS

the test-and-treat strategy, endoscopy-based strategy, and screen-and-treat strategy are recommended to prevent GC based on risk stratification, prevalence, and patients' clinical manifestations and conditions. Challenges contain false-negative results, increasing antibiotic resistance, decreasing eradication rate, and poor retesting rate. Present diagnosis methods are mainly based on invasive endoscopy and noninvasive laboratory testing.

RESULTS

to improve the accuracy and effectiveness and reduce the missed diagnosis, some advances were achieved including newer imaging techniques (such as image-enhanced endoscopy (IEE), artificial intelligence (AI) technology, and quantitative real-time polymerase chain reaction (qPCR) and digital PCR (dPCR).

CONCLUSION

in the article, we summarized the diagnosis methods of H. pylori infection and recent advances, further finding out the opportunities in challenges.

Factors for Negative Result in Serum Anti-Helicobacter pylori IgG Antibody Test in Adult Subjects With Nodular Gastritis: A Single-center Study

Aim: Nodular gastritis has been demonstrated to be strongly associated with Helicobacter pylori infection. The present retrospective study was performed to elucidate factors related to a negative serum antibody test result in adults with nodular gastritis.

Materials and methods: We investigated 116 H. pylori-positive subjects endoscopically diagnosed with nodular gastritis and subjected to a serum anti-H. pylori immunoglobulin G (IgG) antibody test. The degree of gastric mucosal atrophy and the presence of spotty redness in the gastric body and fornix were carefully determined by observations of endoscopic images.

Results: Of the 116 investigated subjects, 108 were positive and 8 negative in serum anti-H. pylori IgG antibody test results. The degree of gastric mucosal atrophy was mild in seven among eight seronegative cases. The levels of pepsinogen II in serum in patients with negative antibody test findings were significantly lower as compared to those found positive, while the pepsinogen I/II ratio tended to be higher in subjects shown negative by the test. Only 1 of 69 with spotty redness was negative in serum anti-H. pylori IgG antibody testing, while 7 of 47 without spotty redness were negative. Multiple logistic regression analysis of subjects with a negative test result revealed that the absence of spotty redness shown by endoscopy was a significant risk factor.

Conclusion: The absence of spotty redness, which may reflect the degree of gastric body inflammation, is a significant factor indicating increased risk for a negative serum anti-H. pylori IgG antibody test result in subjects with nodular gastritis.

Regular arrangement of collecting venules and the Kimura-Takemoto classification for the endoscopic diagnosis of Helicobacter pylori infection: Evaluation in a Western setting

BACKGROUND

The regular arrangement of collecting venules (RAC) and the Kimura-Takemoto classification of atrophic change (KTC) are simple and easy-to-use criteria which have been shown to reliably predict or rule out a Helicobacter pylori infection of the stomach. Although these features have been investigated extensively in Asia, their significance in the West has not been evaluated.

METHODS

In a series of 200 consecutive gastroscopic examinations (single examiner, single center), the presence or absence of RAC and the KTC grade (open type vs closed type) were recorded prospectively. Helicobacter pylori infection was defined as a positive histology or a positive rapid urease test. Furthermore, multivariate analysis of endoscopic predictors of H. pylori infection based on the Kyoto classification of gastritis was performed.

RESULTS

Two hundred patients were examined of which 57 had a H. pylori infection (28%). Both RAC and KTC had excellent negative predictive values of about 90% and sensitivity values of up to 85%. In multivariate analysis, atrophic change and diffuse redness without RAC were significantly associated with H. pylori infection.

CONCLUSION

Regular arrangement of collecting venules and KTC are simple endoscopic features which should be given attention by Western endoscopists and can be easily used to rule out a H. pylori infection of the stomach.

Upper Gastrointestinal Lesions during Endoscopy Surveillance in Patients with Lynch Syndrome: A Multicentre Cohort Study

Simple Summary

Patients with Lynch syndrome are at increased risk of upper gastrointestinal cancer. Recommendations for upper gastrointestinal endoscopy screening vary widely with limited data supporting effectiveness. The aim of our study was to investigate yields of upper gastrointestinal endoscopy screening in a large multicentre cohort of 172 Lynch syndrome mutation carriers. In our study, upper gastrointestinal endoscopy surveillance detects frequent neoplastic lesions particularly after the age of 40 years. Ours results suggest that Lynch patients should be considered for upper gastrointestinal endoscopic and Helicobacter pylori screening.

Abstract

Background: Patients with Lynch syndrome are at increased risk of gastric and duodenal cancer. Upper gastrointestinal endoscopy surveillance is generally proposed, even though little data are available on upper gastrointestinal endoscopy in these patients. The aim of this retrospective study was to evaluate the prevalence and incidence of gastrointestinal lesions following upper gastrointestinal endoscopy examination in Lynch patients. Methods: A large, multicentre cohort of 172 patients with a proven germline mutation in one of the mismatch repair genes and at least one documented upper gastrointestinal endoscopy screening was assessed. Detailed information was collected on upper gastrointestinal endoscopy findings and the outcome of endoscopic follow-up. Results: Seventy neoplastic gastrointestinal lesions were diagnosed in 45 patients (26%) out of the 172 patients included. The median age at diagnosis of upper gastrointestinal lesions was 54 years. The prevalence of cancer at initial upper gastrointestinal endoscopy was 5% and the prevalence of precancerous lesions was 12%. Upper gastrointestinal lesions were more frequent after 40 years of age (p < 0.001). Helicobacter pylori infection was associated with an increased prevalence of gastric, but not duodenal, lesions (p < 0.001). Conclusions: Neoplastic upper gastrointestinal lesions are frequent in patients with Lynch syndrome, especially in those over 40 years of age. The results of our study suggest that Lynch patients should be considered for upper gastrointestinal endoscopic and Helicobacter pylori screening.

Prevalence of Barrett's Epithelium Shown by Endoscopic Observations with Linked Color Imaging in Subjects with Different H. pylori Infection Statuses

Objective This study was conducted to clarify the prevalence of short segment Barrett's esophagus (SSBE) using endoscopic observations with linked color imaging (LCI). In addition, the relationship between the presence of Barrett's epithelium (BE) and the status of H. pylori infection was investigated. Methods The study subjects were 3,353 individuals (2,186 men, 1,167 women; mean age 55.2±9.4 years old) whose status of H. pylori infection had been determined. An endoscopic observation using LCI was performed to examine the distal margin of palisade vessels and confirm the area of BE. The prevalence of BE ≥5 mm in length was investigated. Results BE was diagnosed in 1,884 (56.2%) subjects, with lengths of <10, 10-19, 20-29, and ≥30 mm found in 1,005, 851, 27, and 1, respectively. Its prevalence in H. pylori-negative, H. pylori-positive, and post-eradicated subjects was 41.7%, 64.4%, and 69.9%, respectively (p<0.001). The duration since successful eradication of H. pylori did not affect the prevalence of BE. The degree of gastric mucosal atrophy was higher in cases with BE (p<0.001), although negativity for H. pylori infection and mild gastric mucosal atrophy were significant factors for the development of longer BE. Conclusion A high prevalence of SSBE was noted when LCI was used to determine the area of BE, as the distal end of the palisade vessels was easily visualized. Negativity for H. pylori infection and mild gastric mucosal atrophy were not correlated with SSBE prevalence.

Gastric cancer is highly prevalent in Lynch syndrome patients with atrophic gastritis

BACKGROUND

Although gastric cancer is one of the Lynch syndrome (LS)-related tumors, the clinicopathological features of gastric cancer in patients with LS remain uncertain. To investigate the incidence risk and clinicopathological features of gastric neoplasms in LS, we conducted a retrospective cohort study in Japanese LS patients.

METHODS

LS patients with pathogenic mismatch repair (MMR) gene variants were extracted from the LS registry of the National Cancer Center Hospital, Japan. Cumulative risks of gastric neoplasm, including dysplasia and cancer, were estimated using the Kaplan-Meier method. Gastric atrophy was evaluated endoscopically and/or histologically. Immunohistochemical staining for MMR proteins was performed for all available specimens.

RESULTS

Of 118 eligible patients, 26 patients were diagnosed with 58 gastric neoplasms. The cumulative incidence of gastric neoplasm was 41.0% (95% confidence interval, 26.9-55.0) at the age of 70. Of these, 13 (50%) patients developed synchronous and/or metachronous multiple gastric neoplasms. Among the 49 gastric neoplasms available for detailed pathological evaluation, all were associated with intestinal metaplasia. Immunohistochemically, 42 (86%) were MMR-deficient. The individuals with gastric atrophy had a significantly higher risk of developing gastric neoplasms compared with those without gastric atrophy (26 cases/54 individuals vs. 0 cases/53 individuals) (P = 0.026).

CONCLUSION

LS patients, particularly those with atrophic gastritis, are at high risk of gastric neoplasm and often develop multiple tumors. Endoscopic surveillance for gastric cancer is recommended for LS patients, especially those with atrophic gastritis.

Accuracy of Endoscopic Diagnosis of Helicobacter pylori Based on the Kyoto Classification of Gastritis: A Multicenter Study

Background

There is lack of clinical evidence supporting the value of the Kyoto classification of gastritis for the diagnosis of Helicobacter pylori (H. pylori) infection in Chinese patients, and there aren’t enough specific features for the endoscopic diagnosis of past infections, which is of special significance for the prevention of early gastric cancer (GC).

Methods

This was a prospective and multicenter study with 650 Chinese patients. The H. pylori status and gastric mucosal features, including 17 characteristics based on the Kyoto classification and two newly-defined features unclear atrophy boundary (UAB) and RAC reappearance in atrophic mucosa (RAC reappearance) were recorded in a blind fashion. The clinical characteristics of the subjects were analyzed, and the diagnostic odds ratio (DOR), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), area under the receiver operating characteristics curve (ROC/AUC), and 95% confidence intervals were calculated for the different features, individually, and in combination.

Results

For past infection, the DOR of UAB was 7.69 (95%CI:3.11−19.1), second only to map-like redness (7.78 (95%CI: 3.43−17.7)). RAC reappearance showed the highest ROC/AUC (0.583). In cases in which at least one of these three specific features of past infection was considered positive, the ROC/AUC reached 0.643. For current infection, nodularity showed the highest DOR (11.7 (95%CI: 2.65−51.2)), followed by diffuse redness (10.5 (95%CI: 4.87−22.6)). Mucosal swelling showed the highest ROC/AUC (0.726). Regular arrangement of collecting venules (RAC) was specific for no infection.

Conclusions

This study provides evidence of the clinical accuracy and robustness of the Kyoto classification of gastritis for the diagnosis of H. pylori in Chinese patients, and confirms UAB and RAC reappearance partly supplement it for the diagnosis of past infections, which is of great benefit to the early prevention of GC.

Serum Anti-Helicobacter pylori IgG Antibody Titer in H. pylori-negative Cases with a Different Gastric Mucosal Atrophy Status

Objective This retrospective study was performed to investigate the anti-Helicobacter pylori IgG antibody serum titers in H. pylori-negative subjects with different degrees of gastric mucosal atrophy including C0 grade atrophy. Methods The absence of H. pylori infection was determined based on both negative serum anti-H. pylori IgG antibody test findings and no endoscopic evidence of that infection. Cases negative for the antibody and with positive endoscopic findings of H. pylori infection were defined as H. pylori-positive. The serum anti-H. pylori IgG antibody titers were analyzed in H. pylori-negative (n=1,087), -positive (n=69), and post-eradicated (n=278) subjects. Results The serum antibody titer in subjects with H. pylori-positive endoscopy findings was significantly higher than that in H. pylori-negative subjects, even when the serum titer indicated a negative result. In addition, the anti-H. pylori IgG antibody serum titer was higher in H. pylori-negative subjects with a greater degree of gastric mucosal atrophy. In a comparison between H. pylori-negative C0 and C1 gastric mucosal atrophy cases, the antibody serum titer in those classified as C0 was significantly lower. An analysis of H. pylori post-eradicated cases showed that the serum antibody titer decreased over time after successful eradication. Conclusion The disappearance of H. pylori infection in H. pylori-negative individuals may occur later in those with a greater degree of gastric mucosal atrophy. The serum antibody titer difference between the H. pylori-negative C0 and C1 groups might have been caused by the differences in distribution between H. pylori-uninfected subjects and those in whom the infection had disappeared, thus additional investigation is needed to clarify the significance of gastric mucosal classification including the C0 grade.

The endoscopic predictors of Helicobacter pylori status: a meta-analysis of diagnostic performance

Objective:

The endoscopic findings associated with Helicobacter pylori–naïve status, current infection or past infection are an area of ongoing interest. Previous studies have investigated parameters with a potential diagnostic value. The aim of this study was to perform meta-analysis of the available literature to validate the diagnostic accuracy of mucosal features proposed in the Kyoto classification.

Data sources:

The databases of MEDLINE and Embase, clinicalTrials.gov and the Cochrane Library were systematically searched for relevant studies from October 1999 to October 2019.

Methods:

A bivariate random effects model was used to produce pooled diagnostic accuracy calculations for each of the studied endoscopic findings. Diagnostic odds ratios and sensitivity and specificity characteristics were calculated to identify significant predictors of H pylori status.

Results:

Meta-analysis included 4380 patients in 15 studies. The most significant predictor of an H pylori-naïve status was a regular arrangement of collecting venules (diagnostic odds ratio 55.0, sensitivity 78.3%, specificity 93.8%). Predictors of active H pylori infection were mucosal oedema (18.1, 63.7%, 91.1%) and diffuse redness (14.4, 66.5%, 89.0%). Map-like redness had high specificity for previous H pylori eradication (99.0%), but poor specificity (13.0%).

Conclusion:

The regular arrangement of collecting venules, mucosal oedema, diffuse redness and map-like redness are important endoscopic findings for determining H pylori status. This meta-analysis provides a tentative basis for developing future endoscopic classification systems.

Endoscopic severe mucosal atrophy indicates the presence of gastric cancer after Helicobacter pylori eradication -analysis based on the Kyoto classification

Background

Gastric cancer after Helicobacter pylori (HP) eradication is a crucial clinical challenge today as HP eradication therapy is widely performed. Detecting gastric cancer after HP eradication tends to be difficult with normal white-light endoscopy. In the present study, we aimed to identify easily-evaluated endoscopic findings that indicate the presence of gastric cancer after HP eradication so that endoscopists can consider additional detailed examinations at the site.

Methods

We analyzed the endoscopic images of 43 patients who underwent endoscopic submucosal dissection for early gastric cancer after HP eradication and 119 patients with an HP eradication history who underwent esophagogastroduodenoscopy for a medical checkup. Endoscopic findings were evaluated according to the Kyoto classification of gastritis (atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness) and map-like redness.

Results

Patients with gastric cancer had significantly higher total Kyoto risk scores; more atrophy, intestinal metaplasia, and diffuse redness; and a significantly higher prevalence of map-like redness compared with those without gastric cancer, in the univariate analyses. We used logistic regression analysis with forward selection based on the likelihood ratio to develop a model using atrophy and diffuse redness. Receiver operating characteristic analysis showed that a score of A2 in the Kyoto classification of gastritis (open-type atrophic pattern in the Kimura–Takemoto classification) was an endoscopic marker for the presence of post-HP-eradication gastric cancer.

Conclusions

Endoscopic severe gastric mucosal atrophy is useful to screen patients for gastric cancer after HP eradication.

Fundic gland polyp prevalence according to Helicobacter pylori infection status

BACKGROUND AND AIM

The prevalence of fundic gland polyp (FGP) occurrence has not been clarified in individuals with Helicobacter pylori infection post-eradicated status. This study was performed to examine the relationship between FGP prevalence and H. pylori infection status.

METHODS

We enrolled 3400 subjects (2185 male subjects and 1215 female subjects; mean age 54.7 ± 9.5 years) with known H. pylori infection status and who underwent an upper gastrointestinal endoscopy examination as part of an annual check-up. Subjects without and with H. pylori infection numbered 1617 and 239, respectively, while 1544 had a post-eradication status. The presence of FGP and degree of gastric mucosal atrophy were determined in each subject using an endoscopic method.

RESULTS

Endoscopy findings showed FGPs in 1029 (30.3%) of all subjects. The prevalence ratio of FGP positivity in H. pylori-negative, H. pylori-positive, and post-eradicated subjects was 51.9%, 1.7%, and 12.0%, respectively. Multiple logistic regression analysis revealed that female gender, older age, milder gastric mucosal atrophy, and anti-secretory therapy were significant risk factors for FGP occurrence. As compared with H. pylori-positive subjects, the odds ratios for H. pylori-negative and post-eradication status were 48.3 and 6.6, respectively (P < 0.001). In the post-eradication status subjects, longer duration following bacterial eradication was a significant risk factor for occurrence of FGPs.

CONCLUSION

The risk of FGP occurrence in individuals who have undergone H. pylori eradication treatment is lower as compared with those who have never been infected. However, that risk increases over time following eradication.

Phenotypic variations of gastric neoplasms in familial adenomatous polyposis are associated with endoscopic status of atrophic gastritis

BACKGROUND AND AIM

Gastric neoplasms (GN), including gastric adenoma and carcinoma, are well known as extracolonic manifestations of familial adenomatous polyposis (FAP). We aimed to investigate the clinicopathological features of GN in FAP patients and to clarify their relationship with the endoscopic status of the background mucosa.

METHODS

We analyzed the records of 39 patients who were diagnosed with FAP and underwent esophagogastroduodenoscopy between April 2005 and July 2016. Patients were divided into two groups according to atrophic gastritis (AG) status. Endoscopic findings of GN and background mucosa, and histopathological findings, including phenotypic expression of GN and mutation locus of adenomatous polyposis coli (APC) gene, were evaluated.

RESULTS

Gastric neoplasms were more predominant in the AG-positive group than in the AG-negative group (6/9, 66.7% vs 7/30, 23.3%; P = 0.039). Of 36 GN detected in 13 patients, six GN in five patients were followed and 30 GN in eight patients were endoscopically resected and analyzed. GN in the AG-negative group frequently showed whitish color, were located in the proximal stomach, and presented the gastric immunophenotype compared to GN in the AG-positive group. All GN were intramucosal lesions and were curatively resected regardless of AG status. APC germline mutations were identified in 32 patients. In patients with GN, a significantly higher number of mutation loci were among exons 10-15 (codons 564-1465).

CONCLUSION

Clinicopathological characteristics and phenotypic expressions of GN in FAP patients depend on background mucosa status with or without AG. These findings are useful for detecting GN in FAP patients.

Clinical and endoscopic characteristics of eosinophilic esophagitis in Japan: a case-control study

Background

Eosinophilic esophagitis (EoE) is an allergy-associated clinicopathologic condition gaining an increasing amount of recognition in various areas of the world. While the clinical definition and characteristics may differ depending on country and region, sufficient studies have not yet been performed in Japan.

Objective

To assess the prevalence of EoE among the Japanese population and the clinical features associated with the disease.

Methods

Endoscopic data from January 2012 to October 2018 was gathered from 9 Japanese clinical institutes. EoE, defined as esophageal mucosal eosinophilia of at least 15 eosinophils per high-power field, was determined based on esophageal biopsies. Clinical and endoscopic patterns in the cases with EoE were investigated and compared with 186 age- and sex-matched controls.

Results

From 130,013 upper endoscopic examinations, 66 cases of EoE were identified (0.051%; mean age, 45.2 years [range, 7-79 years]; 45 males). Twenty-five patients (37.9%) with EoE were diagnosed by endoscopy during a medical check-up. Patients with EoE had more symptoms (69.7% vs. 10.8%, p < 0.01) such as dysphagia and food impaction, and more allergies (65.2% vs. 23.7%, p < 0.01) compared with the controls. The prevalence of atrophic gastritis was lower in EoE patients than in the controls (20.0% vs. 33.3%, p < 0.05).

Conclusion

The prevalence of EoE in the Japanese population was 0.051% which was comparable with previous reports in Japan. History of allergies and the absence of atrophic gastritis were associated with EoE.

Endoscopic Kyoto classification of Helicobacter pylori infection and gastric cancer risk diagnosis

Recent advances in endoscopic technology allow detailed observation of the gastric mucosa. Today, endoscopy is used in the diagnosis of gastritis to determine the presence/absence of Helicobacter pylori (H. pylori) infection and evaluate gastric cancer risk. In 2013, the Japan Gastroenterological Endoscopy Society advocated the Kyoto classification, a new grading system for endoscopic gastritis. The Kyoto classification organized endoscopic findings related to H. pylori infection. The Kyoto classification score is the sum of scores for five endoscopic findings (atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness with or without regular arrangement of collecting venules) and ranges from 0 to 8. Atrophy, intestinal metaplasia, enlarged folds, and nodularity contribute to gastric cancer risk. Diffuse redness and regular arrangement of collecting venules are related to H. pylori infection status. In subjects without a history of H. pylori eradication, the infection rates in those with Kyoto scores of 0, 1, and ≥ 2 were 1.5%, 45%, and 82%, respectively. A Kyoto classification score of 0 indicates no H. pylori infection. A Kyoto classification score of 2 or more indicates H. pylori infection. Kyoto classification scores of patients with and without gastric cancer were 4.8 and 3.8, respectively. A Kyoto classification score of 4 or more might indicate gastric cancer risk.

Can image-enhanced endoscopy improve the diagnosis of Kyoto classification of gastritis in the clinical setting?

Endoscopic diagnosis of Helicobacter pylori (H. pylori) infection, the most common cause of gastric cancer, is very important to clarify high-risk patients of gastric cancer for reducing morbidity and mortality of gastric cancer. Recently, the Kyoto classification of gastritis was developed based on the endoscopic characteristics of H. pylori infection-associated gastritis for clarifying H. pylori infection status and evaluating risk factors of gastric cancer. Recently, magnifying endoscopy with narrow-band imaging (NBI) has reported benefits of the accuracy and reproducibility of endoscopic diagnosis for H. pylori-related premalignant lesions. In addition to NBI, various types of image-enhanced endoscopies (IEEs) are available including autofluorescence imaging, blue laser imaging, and linked color imaging. This review focuses on understanding the clinical applications and the corresponding evidences shown to improve the diagnosis of gastritis based on Kyoto classification using currently available advanced technologies of IEEs.

Validity of endoscopic features for the diagnosis of Helicobacter pylori infection status based on the Kyoto classification of gastritis

OBJECTIVES

Evaluation of Helicobacter pylori infection status (non-infection, past infection, current infection) has become important. This study aimed to determine the usefulness of the Kyoto classification of gastritis for diagnosing H. pylori infection status by endoscopy.

METHODS

In this prospective study, 498 subjects were recruited. Seven well-experienced endoscopists blinded to the history of eradication therapy performed the examinations. Endoscopic findings were assessed according to the Kyoto classification of gastritis: diffuse redness, regular arrangement of collecting venules (RAC), fundic gland polyp (FGP), atrophy, xanthoma, hyperplastic polyp, map-like redness, intestinal metaplasia, nodularity, mucosal swelling, white and flat elevated lesion, sticky mucus, depressive erosion, raised erosion, red streak, and enlarged folds. We established prediction models according to a machine learning procedure and compared them with general assessment by endoscopists using the Kyoto classification of gastritis.

RESULTS

Significantly higher diagnostic odds were obtained for RAC (32.2), FGP (7.7), and red streak (4.7) in subjects with non-infection, map-like redness (12.9) in subjects with past infection, and diffuse redness (26.8), mucosal swelling (13.3), sticky mucus (10.2) and enlarged fold (8.6) in subjects with current infection. The overall diagnostic accuracy rate was 82.9% with the Kyoto classification of gastritis. The diagnostic accuracy of the prediction model was 88.6% for the model without H. pylori eradication history and 93.4% for the model with eradication history.

CONCLUSIONS

The Kyoto classification of gastritis is useful for diagnosing H. pylori infection status based on endoscopic findings. Our prediction model is helpful for novice endoscopists. (UMIN000016674).

Linked color imaging identifies important risk factors associated with gastric cancer after successful eradication of Helicobacter pylori

BACKGROUND AND AIMS

Limited studies have evaluated the risk factors of gastric cancer (GC) after eradication of Helicobacter pylori (H pylori) using endoscopic findings. We aimed to investigate GC detection-related endoscopic findings after eradication of H pylori using linked color imaging (LCI), a novel image-enhanced endoscopy.

METHODS

This single-center, cross-sectional study evaluated background mucosa-associated endoscopic findings described in the Kyoto classification of gastritis in patients with newly detected GC after eradication of H pylori (CA group, n = 109) and those without GC (NC group, n = 85) using white-light imaging (WLI) and LCI.

RESULTS

Severe atrophy and map-like redness were significantly more frequent in the CA group than in the NC group using WLI (79.8% vs 63.5%, P = .01; 61.5% vs 37.7%, P = .001, respectively) and LCI (79.8% vs 63.5%, P = .01; 78.0% vs 45.9%, P < .0001, respectively). Regular arrangement of collecting venules (RAC) was significantly less frequent in the CA group than in the NC group using WLI (40.3% vs 64.7%, P = .0009) and LCI (37.6% vs 62.4%, P = .0006). Map-like redness was an independent positive risk factor (WLI: odds ratio [OR], 2.05; 95% confidence interval [CI], 1.09-3.87; P = .03; LCI: OR, 3.62; 95% CI, 1.88-6.97; P < .001), whereas RAC was an independent negative risk factor (WLI: OR, 0.42; 95% CI, 0.21-0.82; P = .01; LCI: OR, 0.46; 95% CI, 0.23-0.93, P = .03) for detection of GC after eradication of H pylori.

CONCLUSIONS

Map-like redness, which was identified more frequently using LCI than WLI, and the absence of RAC were associated with detection of GC after eradication of H pylori.

Long-term effect of Helicobacter pylori eradication on prevalence of reflux esophagitis

BACKGROUND AND AIM

This study aimed to clarify the long-term effect of Helicobacter pylori eradication on the prevalence of reflux esophagitis (RE).

METHODS

We enrolled 8123 individuals (male 5286, female 2837; mean age 54.2 ± 9.3 years) who visited our medical center for an annual checkup between April 2016 and December 2018 and in whom the status of H. pylori infection could be determined. The presence of endoscopically proven RE was determined and compared based on that infection status.

RESULTS

Reflux esophagitis was observed in 898 subjects (11.1%). The rates of prevalence in subjects without and with H. pylori infection and with a post-eradication status were 14.0%, 3.7%, and 10.1%, respectively (P < 0.001). Multiple logistic regression analysis of those positive for RE showed male gender, elevated body mass index, habitual drinking, habitual smoking, larger diaphragmatic hiatus size, and milder gastric mucosal atrophy to be significant risk factors. As compared with H. pylori negative, the odds ratios for H. pylori-positive and post-eradication status were 0.225 and 0.703, respectively. When post-eradication subjects were divided according to duration following eradication, RE prevalence was increased in association with a longer duration. Multiple logistic regression analysis revealed longer duration after H. pylori eradication to be a significant risk factor for RE.

CONCLUSIONS

The risk of RE developing in individuals following eradication of H. pylori is considered to be lower as compared with those never infected. However, the risk for RE increases as the period following H. pylori eradication is extended.

Association between a regular arrangement of collecting venules and absence of Helicobacter pylori infection in a European population

BACKGROUND AND AIMS

Helicobacter pylori is the major cause of gastritis and gastritis-associated diseases. Detection of a regular arrangement of collecting venules (RAC) in the lesser gastric curvature correlates with negative H pylori status with a sensitivity and negative predictive value (NPV) higher than 90% in Asian countries. The aim of the study was to evaluate the value of RAC as a diagnostic method of H pylori infection in a European population.

METHODS

A prospective study with high-definition endoscopes without magnification was performed by 3 endoscopists. The presence of starfish-like minute points regularly distributed throughout the lesser curvature of the gastric body was considered RAC positive (RAC+). Gastric biopsies were performed during the procedure for H pylori diagnosis.

RESULTS

One hundred forty patients were included from February 2017 to May 2018. The prevalence of H pylori infection was 31% and 47 of 140 patients (34%) were RAC+; 13 of 23 patients in whom H pylori was eradicated were RAC+. The mean age of RAC+ patients was lower (44.4 vs 52.4 years, P = .004) and they had less- significant endoscopic findings (9; 19.1% vs 38; 80.9%; P = .017). Gender, use of nonsteroidal anti-inflammatory drugs, antithrombotic or anticoagulants treatments, and a history of H pylori eradication did not show differences in the RAC pattern. The absence of RAC was associated with H pylori infection in 47.3% (44/93) of cases. In contrast, all RAC+ patients were free of H pylori infection, with sensitivity and NPV of 100% for the exclusion of H pylori infection.

CONCLUSION

The presence of RAC+ in the lesser curvature evaluated with high-definition endoscopy can accurately identify patients without H pylori.

Prevalence of Autoimmune Gastritis in Individuals Undergoing Medical Checkups in Japan

Objective Based on both endoscopic findings and serum auto-antibody levels, we determined the prevalence of autoimmune gastritis (AIG), which has not been previously reported, in individuals who underwent health checkup examinations in Japan. Methods At total of 6,739 subjects (4,288 males, 2,451 females; mean age 52.1 years) underwent an upper gastrointestinal endoscopic examination as part of an annual medical checkup. Those suspected to have AIG based on endoscopic evidence of proximal-predominant gastric mucosal atrophy were further examined for the presence of anti-parietal cells and anti-intrinsic factor antibodies, with a final diagnosis of AIG made in cases found to be positive for either or both of those factors. Results Of the 6,739 examined subjects, 46 were suspected to have AIG based on the endoscopic findings, of whom 33 were finally diagnosed with AIG, for an overall prevalence 0.49% (females 0.65%, males 0.40%). Seven with AIG also had thyroid disease, including Hashimoto's and Basedow disease, while none with AIG showed anemia in blood test findings. The prevalence of AIG was not different regardless of the H. pylori infection status (negative, positive, post-eradicated). Conclusion In individuals who underwent an upper gastrointestinal endoscopic examination as part of an annual checkup in Japan, the prevalence of AIG was 0.49%. We concluded that it is not uncommon for asymptomatic and healthy individuals to have AIG, and propose that additional studies are needed to clarify its prevalence as well as to establish the criteria used for diagnosis.

Prevention of gastric cancer by Helicobacter pylori eradication: A review from Japan

Japan introduced a Helicobacter pylori eradication therapy strategy in 2013, with the aim of decreasing the number of gastric cancer‐related death, the number of new cases of gastric cancer, and associated medical costs. Five years have passed since then, but no reduction in the annual number of gastric cancer has been observed. In addition, it was suggested that the number of deaths due to gastric cancer could be reduced to 30,000 a year by 2020, but the annual death toll in 2017 remained at more than 45,000. Based on the above evidence, it was examined whether it was possible to reach the target value based on the data from the last 5 years. The number of deaths per year in 2020 is predicted to be more than 40,000, which is clearly different from the target value. Logically, the effect of the strategy might appear by 2023. However, there is a possibility that the risk of gastric cancer may increase in some populations due to the influence of proton pump inhibitors and dysbiosis in the gastric microbiome. To solve these problems, combined therapy with PPIs and aspirin for patients after H pylori eradication should be considered.

A multicenter observational study on the clinicopathological features of gastric cancer in young patients

BACKGROUND

The details of gastric cancer in young patients remain unclear because of the low prevalence of the disease. This study aimed to clarify the clinicopathological features and prognosis of gastric cancer in young patients.

METHODS

From January 2007 to January 2016, patients in their 20s and 30s who were diagnosed with primary gastric cancer at 4 hospitals were enrolled. Their clinical characteristics and prognosis were evaluated.

RESULTS

The total number of patients was 72. The median age was 36 years, and the ratio of males to females was 1:1. The dominant histological type was undifferentiated type (66/72, 92%). Helicobacter pylori (H. pylori) was positive in 81% (54/67). Although there were some asymptomatic patients in stages I-III, all stage IV patients had some clinical symptoms at the diagnosis. The percentage of stage IV was significantly higher in patients in their 20s than in those in their 30s (75% vs. 25%, P < 0.001). The Kaplan-Meier method showed that the overall survival of patients in their 20s was significantly lower than that of patients in their 30s (P = 0.037).

CONCLUSIONS

A high rate of H. pylori infection was revealed in young gastric cancer patients. The patients in their 20s had a worse prognosis than those in their 30s. We should consider examining the H. pylori infection status for young patients as well as older patients to identify high-risk populations.

Relationship of Helicobacter pylori Infection with Gastric Black Spots Shown by Endoscopy

Objective The recently reported endoscopic finding of black spots is defined as black pigmentation in gastric mucosa. We attempted to clarify the relationship between the Helicobacter pylori infection status and black spot occurrence. Methods The study subjects were 1,600 individuals who underwent an annual medical checkup and whose H. pylori status could be determined. Upper endoscopic examinations were performed in all, and the presence of black spots in the stomach as well as the degree of gastric mucosal atrophy were determined. Results Among the 1,600 enrolled subjects, 784 underwent eradication for H. pylori, of whom 144 were originally H. pylori-positive and 672 H. pylori-negative. Black spots in the stomach were observed in 156 (9.8%). The rate of prevalence of black spots in the H. pylori-positive and H. pylori-negative subjects was 2.1% and 1.5%, respectively, while that in subjects after undergoing eradication of H. pylori was 18.2%. A multiple logistic regression analysis demonstrated that an older age and post-eradication status were significant factors for black spot occurrence, while proton pump inhibitor treatment showed a tendency to be a risk factor. In subjects with post-eradication status, a higher grade of gastric mucosal atrophy was a significant risk factor for the occurrence of black spots. Conclusion H. pylori post-eradication status and an older age were significant factors related to the appearance of black spots, and a higher grade of gastric mucosal atrophy was also a significant risk factor in subjects who had undergone successful eradication.

Correlations of the Gastric and Duodenal Microbiota with Histological, Endoscopic, and Symptomatic Gastritis

Mucosal inflammation is characterized by neutrophil and mononuclear cell infiltration. This study aimed to determine the gastric and duodenal microbiota associated with histological, endoscopic, and symptomatic gastritis. Dyspeptic adults who presented for evaluation were included. Subjects with either comorbidities or recent drug intake were excluded. Three endoscopic biopsies were obtained from the antrum, body, and duodenum. Next-generation sequencing for 16S ribosomal RNA V1⁻V2 hypervariable regions was performed. The correlation between the composition of microbiota and the degree of inflammatory cell infiltration, endoscopic findings, and Patient Assessment of Gastrointestinal Disorders Symptom Severity Index (PAGI-SYM) score was analyzed. In 98 included subjects, microbial communities in the antrum and body showed Bray⁻Curtis similarity; however, those in the duodenum showed dissimilarity. Histological and endoscopic gastritis was associated with the abundance of Helicobacter pylori and that of commensal bacteria in the stomach. The abundances of Variovorax paradoxus and Porphyromonas gingivalis were correlated with histological gastritis, but not with endoscopic or symptomatic gastritis. The total PAGI-SYM score showed a stronger correlation with the duodenal microbiota (Prevotella nanceiensis and Alloprevotella rava) than with the gastric microbiota (H. pylori, Neisseria elongate, and Corynebacterium segmentosum). Different correlations of the gastric and duodenal microbiota with histological, endoscopic, and symptomatic gastritis were observed for the first time at the species level. H. pylori-negative gastritis is not associated with endoscopic or symptomatic gastritis. Only H. pylori-induced endoscopic gastritis requires gastric cancer surveillance. Owing to the weak correlation with H. pylori, symptomatic gastritis should be assessed separately from histological and endoscopic gastritis.

Long-term recurrent bleeding risk after endoscopic therapy for definitive colonic diverticular bleeding: band ligation versus clipping

BACKGROUND AND AIMS

Very few prospective studies with over 100 samples have evaluated the long-term outcomes of endoscopic therapy for colonic diverticular bleeding (CDB). This study sought to elucidate the recurrent bleeding risk of endoscopic band ligation versus clipping for definitive CDB based on stigmata of recent hemorrhage (SRH).

METHODS

Patients emergently hospitalized for acute lower GI bleeding and examined by high-resolution colonoscopy were enrolled. Better visualization of SRH from a diverticulum was obtained using a water-jet device. Endoscopic band ligation or clipping was performed as first-line treatment, and patients were prospectively followed after discharge.

RESULTS

No statistical difference was found between the ligation (n = 61) and clipping (n = 47) groups in baseline characteristics or follow-up period. The probability of 1-year recurrent bleeding was 11.5% in the ligation group versus 37.0% in the clipping group (P = .018). No patients required surgery or experienced perforation. One patient in the ligation group experienced diverticulitis the next day. In patients with recurrent bleeding within 7 days, the recurrent bleeding site was the same diverticulum, and ulceration was found in the ligation group on repeat colonoscopy. In patients with recurrent bleeding after 2 months, repeat colonoscopy identified that the recurrent bleeding site was different, and scar formation was seen in the ligation group. The left side of the colon was an independent predictor for recurrent bleeding in the ligation group but not in the clipping group.

CONCLUSIONS

Band ligation for definitive CDB has better outcomes than clipping during long-term follow-up after endoscopic therapy, probably because of complete elimination of the diverticulum. CDB can recur at the same diverticulum in the short term but at a different diverticulum in the long term.

Influence of the Degree of Gastric Mucosal Atrophy on the Serum Lipid Levels Before and After the Eradication of Helicobacter pylori Infection

Objective To clarify the influence of the degree of gastric mucosal atrophy on the serum lipid levels before and after the eradication of Helicobacter pylori infection. Methods The subjects were individuals who underwent an annual detailed medical checkup. Serum anti-H. pylori IgG antibody detection and upper endoscopic examinations were performed in all subjects. Gastric mucosal atrophy was evaluated by the classification of Kimura and Takemoto. The serum levels of total cholesterol, high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC), LDLC/HDLC ratio, and triglycerides were compared among the different degrees of gastric mucosal atrophy in H. pylori-positive subjects. In addition, changes in those serum lipid levels during a two-year period were compared among H. pylori post-eradication cases that showed different degrees of gastric mucosal atrophy prior to eradication. Results In subjects with higher degrees of gastric mucosal atrophy, the serum levels of total cholesterol, LDLC, and triglycerides were elevated. Furthermore, the LDLC/HDLC ratio in subjects with moderate and severe grades of gastric mucosal atrophy was significantly higher than in subjects with mild atrophy. In subjects with higher degrees of gastric mucosal atrophy, the serum level of LDLC and the LDLC/HDLC ratio were decreased following eradication of H. pylori. Conclusion Lipid metabolism is influenced by the degree of gastric mucosal atrophy present before the eradication of H. pylori, and the favorable effects of such eradication are significant in patients with higher degrees of atrophy.

Prevalence of Multiple White and Flat Elevated Lesions in Individuals Undergoing a Medical Checkup

Objective The pathogenesis of multiple white and flat elevated lesions in the stomach has not been elucidated. We investigated the prevalence of such lesions and their characteristics in affected individuals. Methods The subjects were 1,995 individuals (1,320 men, 675 women; mean age 54.2±9.5 years) who visited our medical center for a comprehensive annual medical checkup and in whom the status of Helicobacter pylori infection could be determined. The presence of multiple white and flat elevated lesions in the stomach and the degree of gastric mucosal atrophy were evaluated using endoscopic findings. Results Multiple white and elevated lesions in the stomach were observed in 60 subjects (3.0%), who were predominantly women and older in comparison to those without such lesions. The prevalence rates of these lesions in H. pylori-positive and H. pylori-negative and in post-eradicated subjects were 0.5%, 1.3%, and 4.6%, respectively. A multiple logistic regression analysis demonstrated that post-eradication status, female gender, older age, and a higher grade of gastric mucosal atrophy were significant risk factors for the occurrence of multiple white and elevated lesions. Conclusion Multiple white and elevated lesions were frequently observed in subjects with successful H. pylori eradication.

Accuracy of Endoscopic Diagnosis for Mild Atrophic Gastritis Infected with Helicobacter pylori

Background/Aims

This study examined the accuracy of endoscopic evaluation for determining the Helicobacter pylori infection status in patients with mild atrophy who might not exhibit characteristic endoscopic findings.

Methods

Forty endoscopists determined the H. pylori infection status of 50 randomly presented H. pylori-positive and H. pylori-negative cases on the basis of a list of established findings.

Results

The median clinical endoscopy experience was 7 years (range, 1–35 years), including 22 board-certified endoscopists (55%) of the Japan Gastroenterological Endoscopy Society. The mean accuracy rate of endoscopic diagnosis was 67% and was unrelated to experience status (experienced vs. trainee: 69% vs. 65%, p=0.089) and total years of experience (R² =0.022). The most frequently selected endoscopic findings were regular arrangement of collecting venules (59%), atrophy (45%), and red streak (22%), which had fair accuracy rates of 67%, 65%, and 73%, respectively. By contrast, the accuracy rates of nodularity (89%) and mucosal swelling (77%) were highest. The 20 endoscopists who more frequently identified these findings diagnosed H. pylori infection significantly more accurately than did the other endoscopists (71% vs. 64%, p=0.008).

Conclusions

Careful attention to nodularity and mucosal swelling in patients with mild atrophy may enhance diagnosis, enable prompt treatment, and avoid possible long-term carcinogenesis.

Effects of Helicobacter pylori eradication on serum lipid levels

The purpose was to clarify the effects of Helicobacter pylori (H. pylori) eradication on the changes in serum lipid levels by comparing subjects with and without continuous H. pylori infection. The study subjects were 774 individuals (males 536, females 238, mean age 52.6 years) who visited between April 2013 and March 2016 for annual medical checkups. Serum total cholesterol, high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC), and triglyceride levels, and LDLC/HDLC ratio were compared between the subjects with and without H. pylori infection, as well as those with H. pylori eradication subjects. The HDLC level in the H. pylori-positive group was significantly lower as compared to the H. pylori-negative group. The serum level of HDLC in subjects with successful eradication of H. pylori tended to be higher, while the serum levels of total cholesterol, LDLC, and triglycerides tended to be lower in comparison to subjects with continuous H. pylori infection. In addition, the LDLC/HDLC ratio in the H. pylori-positive group was significantly higher than that in the H. pylori-negative group, and successful H. pylori eradication tended to reduce that ratio. In conclusion, successful eradication of H. pylori may have favorable effects on lipid metabolism.