Natural history of Helicobacter pylori infection

Molecular Mechanisms of Biofilm Formation in Helicobacter pylori

BACKGROUND

Biofilm formation in Helicobacter pylori (H. pylori) helps bacteria survive antibiotic exposure and supports bacterial colonization and persistence in the stomach. Most of the published articles have focused on one aspect of the biofilm. Therefore, we conducted the current study to better understand the mechanism of biofilm formation, how the biofilm contributes to antibiotic resistance, and how the biofilm modifies the medication delivery mechanism.

METHODS

We conducted a literature review analysis of the published articles on the Helicobacter pylori biofilm between 1998 and 2024 from the PubMed database to retrieve eligible articles. After applying the inclusion and exclusion criteria, two hundred and seventy-three articles were eligible for our study.

RESULTS

The results showed that biofilm formation starts as adhesion and progresses through micro-colonies, maturation, and dispersion in a planktonic form. Moreover, specific genes modulate each phase of biofilm formation. Few studies have shown that mechanisms, such as quorum sensing and diffusible signal factors, enhance coordination among bacteria when switching from biofilm to planktonic states. Different protein expressions were also observed between planktonic and biofilm strains, and the biofilm architecture was supported by exopolysaccharides, extracellular DNA, and outer membrane vesicles.

CONCLUSIONS

This infrastructure is responsible for the increased survival of bacteria, especially in harsh environments or in the presence of antibiotics. Therefore, understanding the biofilm formation for H. pylori is crucial. This study illustrates biofilm formation in H. pylori to help improve the treatment of H. pylori infection.

Helicobacter pylori cagA, vacA, iceA and babA Genotypes from Peruvian Patients with Gastric Intestinal Metaplasia

We explored the clinical-stage association of gastric intestinal metaplasia (IM) compared to cases of chronic non-atrophic gastritis (CNAG) and its relationship with virulence genotypes of Helicobacter pylori (H. pylori) clinical isolates from patients with dyspepsia in Peru. This study was cross-sectional and included 158 H. pylori clinical isolates; each isolate corresponded to a different Peruvian patient, genotyped by polymerase chain reaction to detect cagA gene and EPIYA motifs, the vacA gene (alleles s1, s2, i1, i2, d1, d2, m1, m2 and subtypes s1a, s1b and s1c), the iceA gene (alleles 1 and 2), and the babA gene (allele 2). We observed that 38.6% presented with IM and that all clinical isolates were CagA positive. The EPIYA-ABC motif was predominant (68.4%), and we observed a high frequency for the vacA gene alleles s1 (94.9%), m1 (81.7%), i1 (63.9%), and d1 (70.9%). Strains with both iceA alleles were also detected (69.6%) and 52.2% were babA2 positive. In addition, it was observed that the cagA+/vacAs1m1 (PR: 2.42, 1.14 to 5.13, p < 0.05) and cagA+/vacAs1am1 (PR: 1.67, 1.13 to 2.45, p < 0.01) genotypes were associated with IM. Our findings revealed the cagA and vacA risk genotypes predominance, and we provided clinically relevant associations between Peruvian patients with H. pylori infection and IM clinical stage.

Correlation of chronic atrophic gastritis with gastric-specific circulating biomarkers

BACKGROUND AND STUDY AIMS

It has been suggested that the combined detection of multiple serum biomarkers can effectively screen out the high-risk population of chronic atrophic gastritis in the general population. Therefore, it is necessary to establish an effective predictive model of chronic atrophic gastritis.

PATIENTS AND METHODS

Serum biopsies were assessed using five stomach-specific circulating biomarkers pepsinogen I (PGI), PGII, PGI/II ratio, anti- H. pylori antibody, and gastrin-17 (G-17) to identify high-risk individuals and evaluate the risk of developing chronic atrophic gastritis.

RESULTS

In the cross-sectional analysis, PGII, the PG ratio, G17, anti- H. pylori IgG were positively associated with the presence of chronic atrophic gastritis, and combined prediction of the five biomarkers was more accurate than single-factor prediction ((0.692 vs 0.54(PG1), 0.604 (PGⅡ), 0.616(PGI/II ratio), 0.629(G-17)).

CONCLUSION

The combination of PGI, PGII, the PGI/II ratio, G17, and anti-H. pylori antibodies for serological analysis are helpful to screen chronic atrophic gastritis high-risk subjects from the general population and recommend that these people carry out further endoscopy and biopsy.

Helicobacter hepaticus and Helicobacter bilis in liver and biliary cancers from ATBC and PLCO

BACKGROUND

Helicobacter species (spp.) have been detected in human bile and hepatobiliary tissue Helicobacter spp. promote gallstone formation and hepatobiliary tumors in laboratory studies, though it remains unclear whether Helicobacter spp. contribute to these cancers in humans. We used a multiplex panel to assess whether seropositivity to Helicobacter (H.) hepaticus or H. bilis proteins was associated with the development of hepatobiliary cancers in the Finnish Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, and US-based Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO).

METHODS

We included 62 biliary and 121 liver cancers, and 190 age-matched controls from ATBC and 74 biliary and 105 liver cancers, and 364 age- and sex-matched controls from PLCO. Seropositivity to 14 H. hepaticus and H. bilis antigens was measured using a multiplex assay. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for major hepatobiliary cancer risk factors and Helicobacter pylori serostatus.

RESULTS

Seropositivity to the H. bilis antigen, P167D, was associated with more than a twofold higher risk of liver cancer (OR: 2.38; 95% CI: 1.06, 5.36) and seropositivity to the H. hepaticus antigens HH0407 or HH1201, or H. bilis antigen, HRAG 01470 were associated with higher risk of biliary cancer (OR: 5.01; 95% CI: 1.53, 16.40; OR: 2.40; 95% CI: 1.00, 5.76; OR: 3.27; 95% CI: 1.14, 9.34, respectively) within PLCO. No associations for any of the H. hepaticus or H. bilis antigens were noted for liver or biliary cancers within ATBC.

CONCLUSIONS

Further investigations in cohort studies should examine the role of Helicobacter spp. in the etiology of liver and biliary cancers.

The influence of gut microbiota on circulating inflammatory cytokines and host: A Mendelian randomization study with meta-analysis

AIMS

The gut microbiota has been found to be altered in different inflammatory disorders, but its involvement in the regulation of inflammatory cytokines remains unclear. Therefore, this study aimed to investigate the impacts of gut microbiota on circulating inflammatory cytokines and their potential roles in host diseases.

MAIN METHODS

Two-sample Mendelian randomization (MR) analyses were conducted using summary-level data from genome-wide association studies (GWAS) to identify significant causal associations between 196 gut microbiota and 41 inflammatory cytokines. Meta-analysis was applied to test the robustness of the results. Enrichment analyses of identified cytokines were further utilized to infer the effects of gut microbiota on the host.

KEY FINDINGS

The MR analyses and meta-analyses identified the following significant causal associations: phylum Euryarchaeota on interleukin-2 (IL-2) (βIVW = 0.085, P = 1.5 × 10-2) and interleukin-8 (IL-8) (βIVW = 0.065, P = 4.1 × 10-2), phylum Tenericutes and class Mollicutes on macrophage inflammatory protein 1a (MIP1a) (βIVW = -0.142, P = 7.0 × 10-3), class Bacilli on hepatocyte growth factor (HGF) (βIVW = -0.106, P = 2.5 × 10-2), order Enterobacteriales on monocyte chemoattractant protein-1 (MCP1) (βIVW = 0.182, P = 1.8 × 10-2), and genus Lachnospiraceae NC2004 group on TNF-related apoptosis-inducing ligand (TRAIL) (βIVW = -0.207, P = 6.0 × 10-4). Enrichment analyses suggested that phylum Euryarchaeota and order Enterobacteriales might be risk factors for certain autoimmune diseases and neoplasms, while the phylum Tenericutes may have a protective effect.

SIGNIFICANCE

This study represents the first evidence confirming the causal effect of specific gut microbial taxa on circulating inflammatory cytokines and sheds light on their potential roles in the development and progression of various host diseases.

Diagnostic and therapeutic recommendations on Helicobacter pylori infection. Recommendations of the Working Group of the Polish Society of Gastroenterology

Helicobacter pylori remains a major health problem worldwide, causing considerable morbidity and mortality due to peptic ulcer disease and gastric cancer. These guidelines constitute an update of the previous "Recommendations on the diagnosis and management of Helicobacter pylori infection" issued in 2014. They have been developed by a Task Force organized by the Governing Board of the Polish Society of Gastroenterology. They discuss, with particular emphasis on new scientific data covering papers published since 2014: the epidemiology, clinical presentation, diagnostic principles and criteria for the diagnosis, and recommendations for the treatment of H. pylori infection. The guidelines in particular determine which patients need to be tested and treated for infection. The Task Force also discussed recommended treatment algorithms. Accordingly, a combination of available evidence and consensus-based expert opinion were used to develop these best practice advice statements. It is worth noting that guidelines are not mandatory to implement but they offer advice for pragmatic, relevant and achievable diagnostic and treatment pathways based on established key treatment principles and using local knowledge and available resources to guide regional practice.

ROLE OF INCISURA ANGULARIS BIOPSY IN GASTRITIS STAGING AND RISK ASSESSMENT OF GASTRIC CÂNCER

BACKGROUND

Gastric atrophy (GA) and intestinal metaplasia (IM) are early stages in the development of gastric cancer. Evaluations are based on the Updated Sydney System, which includes a biopsy of the incisura angularis (IA), and the Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastritis Assessment using Intestinal Metaplasia (OLGIM) gastric cancer risk staging systems.

OBJECTIVE

To compare the OLGA and OLGIM classifications with and without IA biopsy. In addition, to determine the prevalence of Helicobacter pylori (HP) and pre-neoplastic changes (GA and IM) in different biopsied regions and to identify the exclusive findings of IA.

METHODS

Observational, prospective, descriptive, unicentric study with 350 patients without a diagnosis of gastric cancer, who underwent upper digestive endoscopy with biopsies at Gastroclínica Itajaí, from March 2020 to May 2022. The histopathological classification of gastritis followed the Updated Sydney System, and the gastric cancer risk assessment followed the OLGA and OLGIM systems. The methodology applied evaluated the scores of the OLGA and OLGIM systems with and without the assessment of the IA biopsy. Statistical analysis was performed using descriptive measures (frequencies, percentages, mean, standard deviation, 95% confidence interval). Ranks were compared using the Kruskal-Wallis or Wilcoxon tests. To analyze the relationship between the frequencies, the bilateral Fisher’s exact test was used. Wilson’s score with continuity correction was applied to the confidence interval.

RESULTS

The median age was 54.7 years, with 52.57% female and 47.43% male patients. The comparison between the used biopsies protocol (corpus + antrum [CA] vs corpus + antrum + incisura angularis [CAI]) and the OLGA and OLGIM stages showed a significant decrease in both staging systems when the biopsy protocol restricted to the corpus and antrum was applied (OLGA CAI vs CA; P=0.008 / OLGIM CAI vs CA; P=0.002). The prevalence of pre-malignant lesions (GA, IM and dysplasia) of the gastric mucosa was (33.4%, 34% and 1.1%, respectively) in the total sample. The antrum region exhibited significantly higher numbers of alteration (P<0.001), except for HP infection, which was present in 24.8% of the patients.

CONCLUSION

Incisura angularis biopsy is important because it increased the number of cases diagnosed in more advanced stages of intestinal metaplasia and atrophy. The study had limitations, with the main one being the relatively small sample size, consisting mostly of healthy individuals, although mostly elderly.

A Genetic and Immunohistochemical Analysis of Helicobacter pylori Phenotypes and p27 Expression in Adenocarcinoma Patients in Jordan

Stomach (gastric) cancer is one of the most prevalent and deadly cancers worldwide and most gastric cancers are adenocarcinomas. Based on prior research, there is an association between Helicobacter pylori (H. pylori) infection together with the frequency of duodenal ulcer, distal gastric adenocarcinoma, mucosa-associated lymphoid tissue (MALT) lymphoma, and antral gastritis. Helicobacter pylori virulence and toxicity factors have been identified before that significantly influence the clinical outcomes of H. pylori infection and gastric adenocarcinoma. However, it remains unclear exactly how different strains of H. pylori affect gastric adenocarcinoma. Current research suggests this involves tumor suppressor genes, like p27 but also H. pylori toxic virulence proteins. Therefore, we quantified known H. pylori genotypes within adenocarcinoma patients to establish the prevalence of known toxins that include cytotoxin-associated gene A (cagA) as well as vacuolating cytotoxin A (vacA) within patients of variable adenocarcinoma diagnosis. This analysis used gastrectomy samples validated for DNA viability. The incidence of H. pylori in adenocarcinoma patients in Jordan was established to be 54.5% positive (ureA gene positive) with cagA genotype occurrence at 57.1%, but also in this population study vacA gene ratios found to be 24.7%:22.1%:14.3%:14.3%. (vacAs1:vacAs2:vacAm1:vacAm2). Using immunohistochemistry (IHC), we confirmed with statistical significance that p27 was dysregulated and suppressed, within nearly all H. pylori vacA genotypes. In addition, within 24.6% of H. pylori samples analyzed was a different bacterial genotype, and curiously that p27 protein expression was retained in 12% of tested adenocarcinoma H. pylori samples. This is suggestive that p27 could be used as a prognostic indicator but also that an unknown genotype could be contributing to the regulatory effects of p27 protein within this bacterial and cellular environment that may include other virulence factors and unknown immune system regulatory changes.

A novel detection technology for early gastric cancer based on Raman spectroscopy

Despite universal endoscopic screening, early detection of gastric cancer is challenging, led researchers to seek for a novel approach in detecting. Raman spectroscopy measurements as a fingerprint of biochemical structure, enable accurate prediction of gastric lesions non-destructively. This study aimed to evaluate the diagnostic power of Raman spectroscopy in early gastric cancer (EGC), and reveal dynamic biomolecular changes in vitro from normal to EGC. To clarify the biochemical alterations in Correa's cascade, Raman spectra of human normal gastric mucosa, intestinal metaplasia, dysplasia, and adenocarcinoma were compared at tissue and cellular levels based on a self-developed data processing program. For effectively identify EGC, Raman spectroscopy was used combined with multiple machine learning methods, including partial least-squares discriminant analysis (PLS-DA), support vector machine (SVM), and convolutional neural network (CNN) with leave-one-out (LOO) cross validation. A total of 450 Raman spectra were investigated in this study. The upregulation of ν_sym(O-P-O) backbone (p < 0.001) was identified as a favorable factor for the diagnosis of EGC, the area under the ROC curve (AUC) was up to 0.918. In addition, higher levels of lactic acid (p < 0.001), lipids (p < 0.001), phenylalanine (p = 0.002), and carotenoids (p < 0.001) were detected in EGC. Multivariate machine learning methods for diagnosis of EGC based on Raman spectroscopy, the sensitivity, specificity, accuracy, and AUC were 91.0%, 100%, 94.8%, and 95.8% for SVM, and 84.8%, 92.0%, 88.8%, and 95.5% for CNN, respectively. Raman spectroscopy can be used as a powerful tool for detecting EGC while elucidating biomolecular dynamics in tumorigenesis. (Chictr.org.cn, ChiCTR2200060720.).

Gastric Antral Mucosal Changes in Children With Intestinal Metaplasia

Objectives: The gastric mucosal change accompanying gastric antral intestinal metaplasia (IM) in the pediatric population and its clinical implications remain unclear. Methods: We retrieved all patients younger than 18 years who had upper GI endoscopy with a pathology diagnosis of antral IM between 2009 and 2020. Each biopsy was evaluated for the presence of dysplasia, Helicobacter pylori, gastritis, and other pathologic changes. Results: A total of 134 patients with antral IM were identified; 72 (53.7%) with coexisting pathology including chronic gastritis (n = 22), reactive gastropathy (n = 16), focal mild chronic inflammation (n = 13), gastric eosinophilia (n = 9), chronic active gastritis associated with (n = 2) and without Helicobacter infection (n = 3), and others (n = 7). The remaining 62 (46.3%) showed isolated IM. Gastric IM increased with age, and was often accompanied by other pathologic changes, especially in female children. Twenty-seven patients had follow up biopsies; 11 of the 27 patients (40.7%) showed persistent IM in at least one repeat biopsies. None demonstrated dysplasia. Conclusions: In children, antral IM increases with age and often coexists with other pathologic changes. Gastric IM could persist for at least months to years in a significant subset of patients with chronic gastritis and gastric eosinophilia.

Clinical relevance of the cagA and vacA s1m1 status and antibiotic resistance in Helicobacter pylori: a systematic review and meta-analysis

BACKGROUND

The role of Helicobacter pylori (H. pylori) virulence factors of such as vacA s1m1 and cagA in designating clinical outcomes and eradication rate has been deeply challenged in the last decade. The goal of this analysis was to identify the potential relevance between cagA and vacA genotypes with reported antibiotic resistance observed in clinical H. pylori isolates.

METHODS

This literature search was conducted in databases such as Clarivate analytics, PubMed, Scopus, EMBASE, DOAJ, and Google Scholar by April 2022, regardless of language restrictions and publication date. Quality of the included studies was assessed by the Newcastle-Ottawa scale. Statistical analysis of retrieved studies was fulfilled using Comprehensive Meta-Analysis software version 2.2. Following quality appraisal of eligible studies, potential association between the status of cagA and vacA genes with resistance to clarithromycin, metronidazole, amoxicillin, tetracycline, and levofloxacin was measured using odds ratio with 95% confidence interval. We also used sensitivity analyses and meta-regression to eliminate the source of heterogeneity from the overall estimates. Publication bias was assessed using funnel plot, Egger's test, Begg's test with the trim and fill procedure to assess the presence and magnitude of publication bias in the included studies.

RESULTS

Our findings suggested that a significant relationship between cagA status ‎and increase resistance ‎to metronidazole (OR: 2.69; 95% CI: 1.24-5.83‎‏‎). In subgroup analysis, we ‎found that in the Western ‎population, infection with cagA-positive strains could be led to increase in ‎the resistance to ‎metronidazole (OR: 1.59; 95% CI: ‎0.78-3.21‎‏‎), ‎amoxicillin (OR: ‎19.68‎; 95% CI: 2.74-‎‎141.18), ‎and ‎levofloxacin (OR: ‎11.33; 95% CI: ‎1.39-‎‎91.85). After implementation of trim and fill method, the adjusted OR was not significantly differed from original estimates which in turn represented our subgroup analysis was statistically robust. On the other hand, vacA ‎genotypes usually ‎reduce the antibiotic resistance of this bacterium, so that vacA s1m1 significantly reduces the ‎resistance to ‎metronidazole (OR: 0.41; 95% CI: 0.20-0.86‎‏‎). Surprisingly, resistance of vacA s2m2 strains to antibiotics was low, the reason may be due ‎to the non-inflammatory properties of strains containing vacA s2m2. The meta-regression and sensitivity analyses successfully reduced the effect of heterogeneity from the overall estimates. In addition, although the pooled OR is reduced after trim and fill adjustment but results do not change the conclusion regarding vacA genotypes and antibiotic resistance.

CONCLUSIONS

According to our findings, it was clearly demonstrated that cagA-positive strains are resistance to metronidazole, especially in Western countries. In Western countries, vacA s1m1 increases resistance to amoxicillin and levofloxacin. Based on the present findings, the vacA s1m1 genotype significantly increases resistance to metronidazole, while the vacA s1m2 decreases resistance to clarithromycin and metronidazole. Resistance to antibiotics in less virulent (vacA s2m2) strains is statistically significant lower than others.

Raman Spectroscopy: A Novel Technology for Gastric Cancer Diagnosis

Gastric cancer is usually diagnosed at late stage and has a high mortality rate, whereas early detection of gastric cancer could bring a better prognosis. Conventional gastric cancer diagnostic methods suffer from long diagnostic times, severe trauma, and a high rate of misdiagnosis and rely heavily on doctors’ subjective experience. Raman spectroscopy is a label-free molecular vibrational spectroscopy technique that identifies the molecular fingerprint of various samples based on the inelastic scattering of monochromatic light. Because of its advantages of non-destructive, rapid, and accurate detection, Raman spectroscopy has been widely studied for benign and malignant tumor differentiation, tumor subtype classification, and section pathology diagnosis. This paper reviews the applications of Raman spectroscopy for the in vivo and in vitro diagnosis of gastric cancer, methodology related to the spectroscopy data analysis, and presents the limitations of the technique.

Rejuvenation of Helicobacter pylori-Associated Atrophic Gastritis Through Concerted Actions of Placenta-Derived Mesenchymal Stem Cells Prevented Gastric Cancer

Chronic Helicobacter pylori infection causes gastric cancer via the progression of precancerous chronic atrophic gastritis (CAG). Therefore, repairing gastric atrophy could be a useful strategy in preventing H. pylori-associated gastric carcinogenesis. Although eradication of the bacterial pathogen offers one solution to this association, this study was designed to evaluate an alternative approach using mesenchymal stem cells to treat CAG and prevent carcinogenesis. Here, we used human placenta-derived mesenchymal stem cells (PD-MSCs) and their conditioned medium (CM) to treat H. pylori-associated CAG in a mice/cell model to explore their therapeutic effects and elucidate their molecular mechanisms. We compared the changes in the fecal microbiomes in response to PD-MSC treatments, and chronic H. pylori-infected mice were given ten treatments with PD-MSCs before being sacrificed for end point assays at around 36 weeks of age. These animals presented with significant reductions in the mean body weights of the control group, which were eradicated following PD-MSC treatment (p < 0.01). Significant changes in various pathological parameters including inflammation, gastric atrophy, erosions/ulcers, and dysplastic changes were noted in the control group (p < 0.01), but these were all significantly reduced in the PD-MSC/CM-treated groups. Lgr5+, Ki-67, H⁺/K⁺-ATPase, and Musashi-1 expressions were all significantly increased in the treated animals, while inflammatory mediators, MMP, and apoptotic executors were significantly decreased in the PD-MSC group compared to the control group (p < 0.001). Our model showed that H. pylori-initiated, high-salt diet-promoted gastric atrophic gastritis resulted in significant changes in the fecal microbiome at the phylum/genus level and that PD-MSC/CM interventions facilitated a return to more normal microbial communities. In conclusion, administration of PD-MSCs or their conditioned medium may present a novel rejuvenating agent in preventing the progression of H. pylori-associated premalignant lesions.

Helicobacter pylori-Induced Inflammation: Possible Factors Modulating the Risk of Gastric Cancer

Chronic inflammation and long-term tissue injury are related to many malignancies, including gastric cancer (GC). Helicobacter pylori (H. pylori), classified as a class I carcinogen, induces chronic superficial gastritis followed by gastric carcinogenesis. Despite a high prevalence of H. pylori infection, only about 1–3% of people infected with this bacterium develop GC worldwide. Furthermore, the development of chronic gastritis in some, but not all, H. pylori-infected subjects remains unexplained. These conflicting findings indicate that clinical outcomes of aggressive inflammation (atrophic gastritis) to gastric carcinogenesis are influenced by several other factors (in addition to H. pylori infection), such as gut microbiota, co-existence of intestinal helminths, dietary habits, and host genetic factors. This review has five goals: (1) to assess our current understanding of the process of H. pylori-triggered inflammation and gastric precursor lesions; (2) to present a hypothesis on risk modulation by the gut microbiota and infestation with intestinal helminths; (3) to identify the dietary behavior of the people at risk of GC; (4) to check the inflammation-related genetic polymorphisms and role of exosomes together with other factors as initiators of precancerous lesions and gastric carcinoma; and (5) finally, to conclude and suggest a new direction for future research.

Helicobacter pylori Infection: Comparison of Knowledge between Health Science and Non-Health Science University Students

Background: Helicobacter pylori (H. pylori), an important human pathogen, is classified as a human carcinogen. It is known to cause dyspepsia, peptic ulcers, and gastric cancer. Awareness regarding H. pylori infections in Saudi Arabia awaits investigation to reduce or even eliminate the infection that would ease the substantial burden of managing H. pylori among both malignant and non-malignant diseases. Aims: The study aims were to (1) assess the knowledge of H. pylori infection, testing, and management among undergraduate students in Saudi Arabia and (2) compare the H. pylori knowledge among health science and non-health science students. Methods: This study involved a cross-sectional online survey among 334 undergraduate students in health science and non-health science colleges at King Saud University, Saudi Arabia, using a valid and reliable author-developed survey. The survey had two sections: the socio-demographic factors and knowledge items regarding H. pylori. Data were collected during the 2019–2020 academic year. Data analysis included descriptive statistics, Chi-square, and Mann–Whitney U test. The knowledge scores were categorized as poor, fair, and good. Results: Less than 10% of the students in both groups had a good knowledge level about H. pylori. The comparison of the overall mean between both groups was non-significant. Moreover, the level of knowledge of the respondents was significantly associated with their university level (p < 0.001), family monthly income (p < 0.007), having heard about H. pylori infection (p < 000.1), and a previous history of H. pylori infection (p < 000.1). Conclusion: The overall knowledge level of Saudi undergraduate students about H. pylori infection was low. Thus, health awareness interventions through educational programs are recommended for improving their knowledge about H. pylori infection and its prevention.

The cost-effectiveness of sequential versus standard triple therapy for Helicobacter pylori eradication in Saudi Arabia

BACKGROUND

The utilization rate of different treatment regimens for Helicobacter pylori infection is believed to be high; however, the cost-effectiveness of these regimens has not been examined before. Therefore, the aim of this study was to examine the cost-effectiveness of the two commonly prescribed treatments for H. pylori infection.

METHODS

The data of.

an open-label, single-center, randomized trial that compared the efficacy of sequential therapy (SQT) (i.e., esomeprazole 20 mg twice daily for 10 days, amoxicillin 1000 mg twice daily for 5 days, then clarithromycin 500 mg and tinidazole 500 mg twice daily for 5 days) to standard triple therapy (STT) (i.e., esomeprazole 20 mg, amoxicillin 1000 mg, and clarithromycin 500 twice daily for 14 days) in the eradication of H. pylori, as confirmed by the negative urea breath test (UBT), were used. Propensity score matching bin bootstrapping, with 10,000 replications and bias correction was conducted to generate the 95% confidence limits. Moreover, probabilistic sensitivity analysis was conducted by varying both the eradication rates and the costs of treatment regimens.

RESULTS

There were 82 and 88 patients who were on SQT and STT, respectively. Patients' mean age was 47 years, and approximately 55% of them were females. The mean treatment costs were SAR 2,075.51 (USD 553.47) and SAR 2,629.26 (USD 701.14) for SQT and STT, respectively. The mean eradication rates for SQT and STT were 63.41% and 67.05%, respectively. The mean difference in costs and eradication rates for SQT versus STT were SAR - 550.75 (95% CI: -563.84- -537.69) and - 3.64% (95% CI: -6.98- 5.88). The use of SQT was more likely to be cost saving and more effective with 56.25% confidence level, in comparison to STT.

CONCLUSION

The use of SQT in the treatment of H. pylori seems to be more cost-effective than STT.

Analysis of the Primary and Post-Treatment Antibiotic Resistance of Helicobacter pylori in the Nanjing Area

BACKGROUND

Resistance of Helicobacter pylori (H. pylori) to antibiotics is increasing worldwide. The study was aimed to understand the current situation of antibiotic resistance in Nanjing and to provide a reasonable basis for clinical selection of antibiotics to cure H. pylori.

OBJECTIVE

To investigate the current status of H. pylori antibiotics resistance in the Nanjing area, and analyze the primary and post-treatment antibiotic resistance of H. pylori in this area.

METHODS

During the period from July 2017 to December 2019, 1533 gastric mucosal specimens from patients with positive H. pylori confirmed by a breath test or rapid urease test were collected for isolation and identification of H. pylori. The agar dilution method was used for the antibiotic resistance test.

RESULTS

The result showed that the resistance rates of H. pylori to amoxicillin, clarithromycin, levofloxacin, furazolidone, tetracycline and metronidazole were 2.74%, 47.03%, 33.59%, 0.91%, 0.52% and 80.76%, respectively in the period of July 2017 to December 2019. The resistance rates of H. pylori (primary vs. post-treatment) to amoxicillin, clarithromycin, levofloxacin, furazolidone, tetracycline and metronidazole were 1.83% vs. 6.08%, 38.62% vs. 77.81%, 27.41% vs. 56.23%, 0.58% vs. 2.13%, 0.33% vs. 1.22%, 78.57% vs. 88.75%, respectively.

CONCLUSION

Antibiotic resistance of H. pylori remained a problem for the effective eradication of this pathogen and its associated diseases in the Nanjing area. For post-treatment eradication patients, clinicians should take into account regional antibiotic resistance rate, personal antibiotic exposure history, economic benefit ratio, adverse antibiotic reactions, antibiotic availability and other aspects.

Chronic stress accelerates the process of gastric precancerous lesions in rats

Background: Gastrointestinal cancers account for 20% of all deaths worldwide. Gastric cancer (GC) patients are susceptible to psychological change, especially depression which is commonly induced by chronic stress. Gastric precancerous lesions (GPL) is an important prodromal stage in the occurrence of gastric cancer. Chronic stress influences the prognosis of GC and may influence the process of GPL as well. Methods: Sixty SD rats were randomly divided into a control group, GPL group, and GPL+CUMS group. In the GPL group, 200μg/mL N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) free drinking method combined with intermittent fasting was applied to establish the GPL animal model. Based on this, we combined the GPL rats with chronic unpredicted mild stress (CUMS) to establish a comprehensive model. We then evaluated their behavior by open field tests and sucrose preference tests. We tested the IL-6, IL-10, TNF-α, Ghrelin, Leptin and Somatostatin (SS) levels in serum and observed the expression of Ghrelin and Gastrokine 2(GKN2) in the gastric mucosa of rats with tumors by immunofluorescence. Results: Our results showed that GPL and GPL+CUMS rats all displayed a significantly decreased total distance and mean velocity traveled in the open field test. The percentages of sucrose preference were significantly decreased in the GPL+CUMS group compared to the control group. In addition, IL-6 and TNF-α were significantly increased in both the GPL and GPL+CUMS groups. Furthermore, the GPL+CUMS group showed significantly increased TNF-α levels in serum compared to the GPL rats. Our results showed that the expression of NF-κB, p53, and BCL-2 were significantly increased while BAX was reduced in the GPL and GPL+CUMS groups. Moreover, Ghrelin and Leptin levels in serum were significantly decreased in the GPL and GPL+CUMS groups. SS levels in serum were significantly increased in the GPL+CUMS group. Additionally, we found that the GPL+CUMS rats with tumors not only had strong expression of GKN2 on the luminal side and the lamina propria of the gastric mucosa and tumor, but also had expression of Ghrelin on the luminal side of the gastric mucosa. The areas that showed strong expression of GKN2 and Ghrelin, are all located around the blood vessels in the tumor. Conclusions: GPL rats under chronic stress would aggravate the conditions of GPL, shorten the process of GPL, and increase the risk of tumorigenesis. In addition, the close monitoring of the mental health of cancer survivors and precancerous lesion patients is suggested to be of great significance in the prevention and treatment of cancer.

Helicobacter pylori and association between its positivity and anatomotopographic settlement in the stomach with the host age range

Helicobacter pylori (H. pylori) is a Gram-negative, helically shaped flagellated bacterium. Major diseases associated with H. pylori infection include peptic ulcer, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. The incidence of H. pylori in the anatomotopographic regions of the stomach, such as antrum, corpus, fundus, and incisura angularis, has been investigated. Do the rates of H. pylori in the settlements change over time according to the age ranges of the hosts? Does this change affect the diseases caused by or related to H. pylori? It is estimated that the outcomes, which have been obtained, may provide a new perspective in terms of understanding the etiopathogenesis of H. pylori-induced diseases. A comprehensive literature search of PubMed/MEDLINE databases had been conducted using a combination of terms, “Helicobacter pylori,” “Sydney System,” “stomach,” “pyloric antrum,” “gastric corpus,” “stomach cancer,” and “Helicobacter pylori and age.” There are very few articles examining the relationship between the topographic locations of H. pylori and host age range in the English language literature. Therefore, it is also purposed to emphasize the outcomes of our current research about the mentioned topic. In our opinion, similar studies should reveal the settlement and age range in the different geographic locations and societies as in our study. We believe that these findings will contribute to the efforts for understanding overtly of H. pylori-induced disease of the stomach.

Changing prevalence of Helicobacter pylori infection in children and adolescents

Helicobacter pylori infection has declined over recent decades. However, its prevalence remains high, and nearly 50% of the global population has been infected. In Korea, seroprevalence has steadily decreased in adults, but the status of H. pylori infection in children is unknown. The current status or trend of H. pylori infection in children is important because it can help estimate H. pylori-related diseases including gastric cancer in later life. In this review, the authors discuss the change in H. pylori infection rate among children and adolescents based on literature reviews and our research.

Pathogenesis Mediated by Bacterial Membrane Vesicles

The release of extracellular vesicles (EVs) is a process conserved across the three domains of life. Amongst prokaryotes, EVs produced by Gram-negative bacteria, termed outer membrane vesicles (OMVs), were identified more than 50 years ago and a wealth of literature exists regarding their biogenesis, composition and functions. OMVs have been implicated in benefiting numerous metabolic functions of their parent bacterium. Additionally, OMVs produced by pathogenic bacteria have been reported to contribute to pathology within the disease setting. By contrast, the release of EVs from Gram-positive bacteria, known as membrane vesicles (MVs), has only been widely accepted within the last decade. As such, there is a significant disproportion in knowledge regarding MVs compared to OMVs. Here we provide an overview of the literature regarding bacterial membrane vesicles (BMVs) produced by pathogenic and commensal bacteria. We highlight the mechanisms of BMV biogenesis and their roles in assisting bacterial survival, in addition to discussing their functions in promoting disease pathologies and their potential use as novel therapeutic strategies.

Long-term follow up of serum pepsinogens in patients with gastric cancer or dysplasia after Helicobacter pylori eradication

BACKGROUND AND AIM

Few studies have evaluated the change in serum pepsinogen (sPG) levels after the eradication of Helicobacter pylori. The aim of this study was to evaluate the effect of H. pylori eradication on sPG levels in patients with gastric cancer/dysplasia in comparison to a control group.

METHODS

We prospectively enrolled 368 patients with gastric cancer/dysplasia and 610 control subjects. H. pylori status and sPG levels were measured before and after eradication. The follow-up time points were classified as < 12, 12-23, 24-35, and ≥ 36 months.

RESULTS

In 179 H. pylori-eradicated patients with gastric cancer/dysplasia and 168 control group subjects, sPG I significantly decreased, and the sPG I/II ratio significantly increased after eradication compared to baseline, and this improvement in sPG values was maintained during all follow-up time points. Significant differences in sPG I and the sPG I/II ratio were observed between the gastric cancer/dysplasia group and the control group < 24 months after eradication. However, these differences in sPG values disappeared after ≥ 24 months of follow up. Moreover, significant differences in the intestinal metaplasia grade were observed between these two groups before eradication until < 24 months after eradication. However, these differences in the intestinal metaplasia grade disappeared after ≥ 24 months of follow up in the corpus.

CONCLUSION

The sPG values and intestinal metaplasia grade (corpus) in the gastric cancer/dysplasia group became similar to those in the control group at long-term follow up after H. pylori eradication. It might be related with the reduction of metachronous gastric neoplasm.

CD103 Promotes the Pro-inflammatory Response of Gastric Resident CD4+ T Cell in Helicobacter pylori-Positive Gastritis

CD103 is considered as a surface marker for the resident immune cells. However, little is known about the intrinsic function of CD103 in infection and inflammation. In this study, we found that CD103 was highly expressed in CD4⁺T cells of the gastric mucosa from patients with H. pylori-positive gastritis. Mucosal resident CD103⁺CD4⁺T cells exhibited an increase in the CD45RO⁺CCR7⁻ effector memory phenotype and high expression of the chemokine receptors CXCR3 and CCR9 compared with those in CD103⁻CD4⁺T cells. An In vitro coculture study demonstrated that H. pylori-specific antigen CagA/VacA-primed dendritic cells (DCs) induced proliferation and IFN-γ, TNF as well as IL-17 production by CD103⁺CD4⁺T cells from patients with H. pylori-positive gastritis, while blocking CD103 with a neutralizing antibody reduced proliferation and IFN-γ, TNF, and IL-17 production by CD103⁺CD4⁺T cells cocultured with DCs. Moreover, immunoprecipitation revealed that CD103 interacted with TCR α/β and CD3ζ, and activation of CD103 enhanced the phosphorylation of ZAP70 induced by the TCR signal. Finally, increased T-bet and Blimp1 levels were also observed in CD103⁺CD4⁺T cells, and activating CD103 increased T-bet and Blimp1 expression in CD4⁺T cells. Our results explored the intrinsic function of CD103 in gastric T cells from patients with H. pylori-positive gastritis, which may provide a therapeutic target for the treatment of gastritis.

Changes in Seroprevalence of Helicobacter pylori Infection over 20 Years in Jinju, Korea, from Newborns to the Elderly

BACKGROUND

The objective of this study was to examine changes in the prevalence of cytotoxic-associated gene A (CagA) positive Helicobacter pylori infection in Jinju, Korea, over the last 20 years.

METHODS

Three cross-sectional analyses were conducted concurrently. A total of 1,305 serum samples were collected from 1994-1995, 2004-2005, and 2014-2015, respectively. The presence of immunoglobulin (Ig) G, IgA, and IgM antibodies against H. pylori CagA protein was examined by western blotting.

RESULTS

Overall, seropositivity for anti-CagA IgG antibody was significantly decreased from 63.2% to 42.5% over the last 20 years (P < 0.001). Anti-CagA IgG seropositivities in children and young adults aged 10-29 years decreased from 1994 (60.0%-85.0%) to 2015 (12.5%-28.9%). The age when plateau of increasing IgG seropositivity was reached in each study period shifted from the 15-19 year-old group in 1994-1995 (85.0%) to the 40-49 year-old group in 2014-2015 (82.5%). Overall seropositive rates of anti-CagA IgA and IgM antibodies did not change significantly either over the last 20 years.

CONCLUSION

H. pylori infection rate in children and young adults declined over 20 years in Jinju, probably due to improved sanitation, housing, or economy.

Compliance, adverse effects and effectiveness of first line bismuth-containing quadruple treatment (Pylera®) to eradicate Helicobacter pylori infection in 200 patients

INTRODUCTION AND OBJECTIVES

quadruple therapy with bismuth is recommended as a first line treatment for Helicobacter pylori (H. pylori) infection. The aim of this study was to evaluate the compliance, adverse effects and effectiveness of this treatment with the new galenic three-in-one capsule formulation containing bismuth subcitrate, metronidazole and tetracycline (Pylera®).

METHODS

a prospective, non-controlled, single center observational study was performed in a cohort of 200 consecutive patients with an untreated H. pylori infection; 58% were female. The subjects were treated for ten days with Pylera® of three capsules four times daily with meals and a proton pump inhibitor taken before breakfast and dinner. The Pylera® capsule contains 140 mg of bismuth subcitrate, 125 mg of metronidazole and 125 mg of tetracycline. The compliance and adverse effects of the treatment were evaluated via telephone contact and via an interview during the clinical revision. Eradication of infection was controlled for at least four weeks after treatment termination via the urea breath test, the stool antigen test with monoclonal antibodies or by histology.

RESULTS

treatment compliance was observed in 96% (192/200) of the patients. Only 28.5% (57/200) of the patients experienced adverse effects, which led to abandoning the treatment in only seven subjects. Severe adverse effects developed in only one case due to Clostridium difficile infection. The effectiveness based on intention to treat was 91.5% (183/200, 95% CI: 87.1-96.8) and per protocol was 95.2% (182/191, 95% CI: 90.9-98.9).

CONCLUSIONS

in our experience, Pylera® is an effective and safe treatment that should be considered as a first line therapeutic option for the eradication of H. pylori infection.

Helicobacter pylori: A Review of Current Diagnostic and Management Strategies

As one of the most prevalent infections globally, Helicobacter pylori (H. pylori) continues to present diagnostic and therapeutic challenges for clinicians worldwide. Diagnostically, the "test-and-treat" strategy is the recommended approach for healthcare practitioners when managing this potentially curable disease. The choice of testing method should be based on several factors including patient age, presenting symptoms, and medication use, as well as test reliability, availability, and cost. With rising antibiotic resistance, particularly of macrolides, care must be taken to ensure that therapy is selected based on regional resistance patterns and prior antibiotic exposure. In the USA, macrolide antibiotic resistance rates in some areas have reached or exceeded a generally accepted threshold, such that clarithromycin triple therapy may no longer be an appropriate first-line empiric treatment. Instead, bismuth quadruple therapy should be considered, while levofloxacin-based or alternative macrolide-containing therapies are also options. Once treated, it is essential to test for eradication as untreated H. pylori is associated with serious complications including peptic ulcer disease, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. This review article aims to consolidate current knowledge of H. pylori infection with a particular emphasis on diagnostic and treatment strategies.

Genetic polymorphisms in the cag pathogenicity island of Helicobacter pylori and risk of stomach cancer and high-grade premalignant gastric lesions

Helicobacter pylori (Hp) infects the stomach of about half of the human population and is strongly associated with the risk of gastric cancer (GC) and its premalignant precursors. The cag pathogenicity island (cagPAI) is a region of the Hp genome encoding for key molecular machinery involved in the infection process. Following a sequencing study, we selected 50 genetic polymorphisms located in seven cagPAI genes and tested their associations with the risk of advanced gastric premalignant lesions and GC in 1220 subjects from various Latin American populations showing the whole spectrum of phenotypes from gastritis to GC. We found that three polymorphisms of cagA are associated with the risk of advanced gastric premalignant lesions (incomplete intestinal metaplasia [ie, Type 2 and 3] or dysplasia), and that six polymorphisms located in cagA, cagL and cagI were associated with risk of GC. When corrected for multiple testing none of the associations were statistically significant. However, scores built by integrating the individual polymorphisms were significantly associated with the risk of advanced gastric premalignant lesions and GC. These results have the potential of establishing markers for risk stratification in the general population, in view of targeting Hp eradication to high-risk population groups.

Early diagnosis of gastric cancer based on deep learning combined with the spectral-spatial classification method

The development of an objective and rapid method that can be used for the early diagnosis of gastric cancer has important clinical application value. In this study, the fluorescence hyperspectral imaging technique was used to acquire fluorescence spectral images. Deep learning combined with spectral-spatial classification methods based on 120 fresh tissues samples that had a confirmed diagnosis by histopathological examinations was used to automatically identify and extract the "spectral + spatial" features to construct an early diagnosis model of gastric cancer. The model results showed that the overall accuracy for the nonprecancerous lesion, precancerous lesion, and gastric cancer groups was 96.5% with specificities of 96.0%, 97.3%, and 96.7% and sensitivities of 97.0%, 96.3%, and 96.6%, respectively. Therefore, the proposed method can increase the diagnostic accuracy and is expected to be a new method for the early diagnosis of gastric cancer.

Prevalence of Helicobacter pylori infection and antibiotic resistance profile in Armenia

Background

The prevalence of Helicobacter pylori infection was never assessed in Armenia, nor was the prevalence of H. pylori resistance against the main antibiotics concerned, despite the fact that these data are fundamental to establish evidence-based recommendations for management of this infection. We aimed to fill this gap by assessing prevalence of H. pylori among adult population in Armenia and resistance of H. pylori strains to clarithromycin and levofloxacin.

Methods

Helicobacter pylori seroprevalence was determined in 217 asymptomatic adult subjects submitted to a health checkup using an ELISA. Molecular methods were used to detect H. pylori in gastric biopsies from 91 adult dyspeptic patients [55 (60.4%) were positive] as well as the mutations associated with clarithromycin resistance by real-time PCR and with levofloxacin by sequencing the gyrA QRDR.

Results

Helicobacter pylori seropositivity was found to be 41.5% globally and increased with age from 13.6% (age 18–25 years) to 83.3% (age > 65 years). Only two cases were found with a A2142/43G mutation causing clarithromycin resistance, and 6 cases showed mutations associated with levofloxacin resistance.

Conclusions

Helicobacter pylori infection is estimated to be about 42% among adults in Armenia and the low clarithromycin resistance allows the use of the standard triple therapy as a first line therapy.

Electronic supplementary material

The online version of this article (10.1186/s13099-019-0310-0) contains supplementary material, which is available to authorized users.

Progress in prevention and treatment of gastric cancer with traditional Chinese medicine

Gastric cancer (GC) is one of the most common malignant tumors of the upper digestive tract, threatening the health of Chinese people seriously. It is often diagnosed at the late stage of the disease because of the lack of specific symptoms and signs in the early stage. However, traditional Chinese medicine (TCM) has good effects in the prevention and treatment of GC. This article reviews the etiology, pathogenesis, syndrome differentiation, and classification of GC, as well as the application of TCM in precancerous lesions of GC, preoperative neoadjuvant chemotherapy of GC, postoperative chemotherapy, and prolonging the life span of GC patients.

Inhibition of bacterial toxin recognition of membrane components as an anti-virulence strategy

Over recent years, the development of new antibiotics has not kept pace with the rate at which bacteria develop resistance to these drugs. For this reason, many research groups have begun to design and study alternative therapeutics, including molecules to specifically inhibit the virulence of pathogenic bacteria. Because many of these pathogenic bacteria release protein toxins, which cause or exacerbate disease, inhibition of the activity of bacterial toxins is a promising anti-virulence strategy. In this review, we describe several approaches to inhibit the initial interactions of bacterial toxins with host cell membrane components. The mechanisms by which toxins interact with the host cell membrane components have been well-studied over the years, leading to the identification of therapeutic targets, which have been exploited in the work described here. We review efforts to inhibit binding to protein receptors and essential membrane lipid components, complex assembly, and pore formation. Although none of these molecules have yet been demonstrated in clinical trials, the in vitro and in vivo results presented here demonstrate their promise as novel alternatives and/or complements to traditional antibiotics.

Helicobacter pylori infection in children: an overview of diagnostic methods

Children differ from adults regarding Helicobacter pylori (H. pylori) infection in many terms. H. pylori infection represents a key factor in the pathogenesis of duodenal ulcer and chronic gastritis in children. H. pylori infection causes some extraintestinal diseases as well as gastrointestinal diseases. Although, among these illnesses in children, symptoms like recurrent abdominal pain are not specific. Moreover, the role of the pathogen in the growth faltering, iron deficiency anemia, and asthma still remains controversial. A reliable method to detect H. pylori infection is a crucial issue, sand is still a matter of active debate. The tests applied for H. pylori diagnosis are grouped as either invasive or non-invasive methods. Invasive methods consist of endoscopic evaluation, the rapid urease test (RUT), histology, and bacterial culture. Non-invasive tests include the urea breath test (UBT), stool antigen test (SAT), serology, and molecular diagnostic approaches. Use of endoscopy is a pre-requisite for all invasive methods and poses difficulties in children as it is a difficult procedure and requires patient's cooperation. For this reason, the non-invasive tests have been commonly used in children, although their accuracy is not very reliable in some cases. Invasive tests may be opted to confirm the diagnosis as and when needed. This review presents the diagnostic tests used to detect H. pylori infection in children.

Helicobacter pylori-Induced DNA Damage Is a Potential Driver for Human Gastric Cancer AGS Cells

Helicobacter pylori is a major cause of gastric cancer. This study was aimed to explore the characteristic of DNA damage induced by H. pylori infection in gastric cancer AGS cells. After infection with H. pylori, the reactive oxygen species (ROS) levels in AGS cells were significantly higher than those in the uninfected cells. Cells with longer comet tails were detected after infection with H. pylori. The number of apurinic/apyrimidinic endonuclease 1- and phosphorylated H2AX-positive cells was significantly increased compared with the number of negative control cells. The expression of pChk1 and pChk2 was significantly upregulated by H. pylori infection. Cell growth was inhibited after H. pylori infection. All these results were dose dependent. The cell alterations were more significant upon infection with H. pylori at a multiplicity of infection (MOI) of 100:1 than at an MOI of 50:1. H. pylori infection can induce DNA single-strand breaks, DNA double-strand breaks, and cell cycle checkpoint activation after ROS generation in the gastric cancer cell line AGS, which is a potential driver for gastric cancer.

Helicobacter pylori Infection and Related Gastrointestinal Diseases in Southeast Asian Countries: An Expert Opinion Survey

Background:

Helicobacter pylori (H. pylori) infection is currently considered as an infectious disease irrespective of symptoms and stage of disease. This study aimed to survey the impact of H. pylori infection and the current management approaches in Southeast Asian countries.

Materials and methods:

This is a survey among 26 experts from 9 Southeast Asian countries (Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand and Vietnam), who attended a meeting to develop the ASEAN consensus on H. pylori management in November 2015.

Results:

The prevalence of H. pylori varied significantly from 20% to 69% among countries, highest in Myanmar and lowest in Malaysia. The rate of H. pylori infection in patients with gastritis, peptic ulcer disease and gastric cancer (GC) also varied significantly, not only among countries but also among regions within the same country. The most common method for H. pylori diagnosis before treatment was rapid urease test, followed by urea breath test. In multi-ethnic countries, some ethnic groups including Chinese, Batak and Minahasanese were considered as having higher risk of GC. There have been no national screening programs for GC in all countries, and a majority of patients with GC were diagnosed in advanced stages with very poor 5-year survival.

Conclusions:

The prevalence of H. pylori infection and its infection rates in related gastrointestinal diseases were significantly different among Southeast Asian countries. The prognosis of patients with GC in the region was very poor. The result of this survey is a platform for future international and regional research collaboration.

Increased H. pylori stool shedding and EPIYA-D cagA alleles are associated with gastric cancer in an East Asian hospital

BACKGROUND

Helicobacter pylori infection increases risk for gastric cancer. Geographic variation in gastric cancer risk has been attributed to variation in carriage and type of the H. pylori oncogene cagA. Colonization density may also influence disease and cagA has been associated with higher shedding in stool. However, the relationship between H. pylori load in the stool and in the stomach is not clear.

METHODS

To investigate possible differences in H. pylori load in the stomach and shedding in stool, H. pylori load and cagA genotype were assessed using droplet digital PCR assays on gastric mucosa and stool samples from 49 urea breath test-positive individuals, including 25 gastric cancer and 24 non-cancer subjects at Henan Cancer Hospital, Henan, China.

RESULTS

Quantitation of H. pylori DNA indicated similar gastric loads among cancer and non-cancer cases, but the gastric cancer group had a median H. pylori load in the stool that was six times higher than that of the non-cancer subjects. While the cagA gene was uniformly present among study subjects, only 70% had the East Asian cagA allele, which was significantly associated with gastric cancer (Fisher's Exact Test, p = 0.03).

CONCLUSION

H. pylori persists in a subset of gastric cancer cases and thus may contribute to cancer progression. In this East Asian population with a high prevalence of the cagA gene, the East Asian allele could still provide a marker for gastric cancer risk.

IMPACT

This study contributes to our understanding of H. pylori dynamics in the context of pathological changes.

Evidence for PTGER4, PSCA, and MBOAT7 as risk genes for gastric cancer on the genome and transcriptome level

Genetic associations between variants on chromosome 5p13 and 8q24 and gastric cancer (GC) have been previously reported in the Asian population. We aimed to replicate these findings and to characterize the associations at the genome and transcriptome level. We performed a fine‐mapping association study in 1926 GC patients and 2012 controls of European descent using high dense SNP marker sets on both chromosomal regions. Next, we performed expression quantitative trait locus (eQTL) analyses using gastric transcriptome data from 143 individuals focusing on the GC associated variants. On chromosome 5p13 the strongest association was observed at rs6872282 (P = 2.53 × 10⁻⁰⁴) and on chromosome 8q24 at rs2585176 (P = 1.09 × 10⁻⁰⁹). On chromosome 5p13 we found cis‐eQTL effects with an upregulation of PTGER4 expression in GC risk allele carrier (P = 9.27 × 10⁻¹¹). On chromosome 8q24 we observed cis‐eQTL effects with an upregulation of PSCA expression in GC risk allele carrier (P = 2.17 × 10⁻⁴⁷). In addition, we found trans‐eQTL effects for the same variants on 8q24 with a downregulation of MBOAT7 expression in GC risk allele carrier (P = 3.11 × 10⁻⁰⁹). In summary, we confirmed and refined the previously reported GC associations at both chromosomal regions. Our data point to shared etiological factors between Asians and Europeans. Furthermore, our data imply an upregulated expression of PTGER4 and PSCA as well as a downregulated expression of MBOAT7 in gastric tissue as risk‐conferring GC pathomechanisms.

Hydrotalcite Can Prevent the Damaging Effects of Helicobacter Pylori on Gastric Epithelial Cells

BACKGROUND

Helicobacter pylori is a major cause of gastric diseases including gastric cancer. This study was aimed to explore whether hydrotalcite can inhibit H. pylori infection of gastric epithelial cells.

METHODS

the gastric epithelial cell line GES-1 and the gastric cancer cell line BGC823 were infected with H. pylori at multiplicities of infections (MOIs) of 50:1 and 100:1. Hydrotalcite was added to cell cultures. Cell apoptosis and cell cycle analysis were performed to measure the situation of cell growth. The main changes of cell ultrastructure were observed by transmission electron microscopy. H. pylori cell adhesion was observed by scanning electron microscopy.

RESULTS

hydrotalcite could significantly inhibit cell apoptosis of GES-1 and cell proliferation of BGC823 induced by H. pylori infection at an MOI of 50:1. Hydrotalcite treatment protected gastric cells from H. pylori infection, and H. pylori adhesion to gastric cells was reduced. However, hydrotalcite could not reverse damage induced by H. pylori infection at an MOI of 100:1.

CONCLUSION

hydrotalcite can protect gastric cells from H. pylori infection when cell damage is not serious. It can weaken the damage of cells induced by H. pylori and decrease H. pylori adhesion to gastric cells.

IVTH BRAZILIAN CONSENSUS CONFERENCE ON HELICOBACTER PYLORI INFECTION

ABSTRACT Significant progress has been obtained since the III Brazilian Consensus Conference on H. pylori infection held in 2012, in Bento Gonçalves, Brazil, and justify a fourth meeting to establish updated guidelines on the current management of H. pylori infection. Therefore, the Núcleo Brasileiro para Estudo do Helicobacter pylori e Microbiota (NBEHPM), association linked to Brazilian Federation of Gastroenterology (FBG) held its fourth meeting again in Bento Gonçalves, RS, Brazil, on August 25-27, 2017. Twenty-six delegates, including gastroenterologists, endoscopists, and pathologists from the five regions of Brazil as well as one international guest from the United States, participated in the meeting. The participants were invited based on their knowledge and contribution to the study of H. pylori infection. The meeting sought to review different aspects of treatment for infection; establish a correlation between infection, dyspepsia, intestinal microbiota changes, and other disorders with a special emphasis on gastric cancer; and reassess the epidemiological and diagnostic aspects of H. pylori infection. Participants were allocated into four groups as follows: 1) Epidemiology and Diagnosis, 2) Dyspepsia, intestinal microbiota and other afections, 3) Gastric Cancer, and, 4) Treatment. Before the consensus meeting, participants received a topic to be discussed and prepared a document containing a recent literature review and statements that should be discussed and eventually modified during the face-to-face meeting. All statements were evaluated in two rounds of voting. Initially, each participant discussed the document and statements with his group for possible modifications and voting. Subsequently, during a second voting in a plenary session in the presence of all participants, the statements were voted upon and eventually modified. The participants could vote using five alternatives: 1) strongly agree; 2) partially agree; 3) undecided; 4) disagree; and 5) strongly disagree. The adopted consensus index was that 80% of the participants responded that they strongly or partially agreed with each statement. The recommendations reported are intended to provide the most current and relevant evidences to management of H. pylori infection in adult population in Brazil.

Demographic, Endoscopic and Histopathologic Features Among Stool H. pylori Positive and Stool H. pylori Negative Patients With Dyspepsia

Background

Dyspepsia is a common presentation for many patients in gastroenterology clinics. Helicobacter pylori (H. pylori) infection is endemic in many countries around the world and its relation to dyspepsia has long been questioned. This study aimed at comparing demographic, endoscopic and histologic features among dyspeptic patients with and without stool H. pylori antigen positivity.

Methods

One hundred and fifty-one consecutive patients with dyspepsia were divided into group I (n = 80) and group II (n = 71) according to positive or negative H. pylori stool antigen testing, respectively. All patients were subjected to history taking, clinical examination, laboratory investigations, abdominal ultrasonography, H. pylori stool antigen detection, and upper gastrointestinal tract endoscopy with four gastric mucosal biopsies for histopathologic examination.

Results

Stool H. pylori antigen negative group included more smokers and consumed much more fast and spicy food than the positive group. The most common endoscopic findings of both groups were gastritis, reflux esophagitis, gastric erosions, peptic ulcer, mucosal nodularity and hiatus hernia and were encountered in 100%, 74.2%, 23.2%, 15.2%, 13.9%, and 13.2% respectively with non-significant difference between both groups except for gastric erosions that were significantly higher in stool H. pylori negative group (P < 0.001). Histologic evidence of gastritis was reported in 100% and 92.9% of patients in group I and group II, respectively. Chronic active gastritis with neutrophil infiltration was significantly higher in group I (P < 0.001). H. pylori bacilli were histologically detected in 83.7% and 47.9% of patients in group I and group II, respectively (P < 0.001).

Conclusion

All patients with dyspepsia in this study had endoscopic evidence of gastritis. Most of these patients had histologic evidence of gastric mucosal inflammation. Consequently, it may be advisable to perform endoscopy on these patients and obtain gastric mucosal biopsies.

H. pylori infection and gastric cancer in Bangladesh: a case-control study

Background:

Like that of other Asian countries gastric cancer (GC) is also a leading cancer in Bangladesh and also a cause for cancer-related mortality. Infection with Helicobacter pylori (H. pylori) is the strongest recognized risk factor for gastric adenocarcinoma. The infection is also prevalent in common people. This case-control study was carried out to find an association between GC and H. pylori infection in the community.

Materials and Methods:

To evaluate association of H. pylori and carcinoma of stomach this study was conducted at National Institute of Cancer Research & Hospital, Dhaka from January 2013 to December 2014. H. pylori status was determined serologically by using H. pylori kit in the department of Biochemistry laboratory of Bangabandhu Sheikh Mujib Medical University. In total, 114 patients with GC and 520 patients not having GC were studied as controls. Logistic regression method was used to calculate the odds ratio.

Results:

Significantly more patients in the case group (86.8%) were found to be seropositive for H. pylori antigen in contrast to the control group (67.5%). All of the cases in the present study were in advanced stage. No significant association between H. pylori seropositivity and tumor location was found. It was noted that undifferentiated gastric carcinoma had slightly more association with H. pylori infection. Younger H. pylori–infected patients had been found to be at higher relative risk for GC than older patients.

Conclusion:

As there is a strong association found between GC and H. pylori infection special emphasis to eradicate H. pylori infection might reduce the incidence of this dreadly disease.

Long-term follow-up of pepsinogen I/II ratio after eradication of Helicobacter pylori in patients who underwent endoscopic mucosal resection for gastric cancer

BACKGROUND

Although the pepsinogen I/II (PGI/II) ratio after Helicobacter pylori eradication is recovered at short-term follow-up, long-term follow-up studies of PGI/II are rare.

METHODS

A total of 773 patients with gastric cancer who underwent endoscopic resection and pepsinogen and H. pylori tests were enrolled. H. pylori was eradicated in these patients. Endoscopic and pepsinogen tests were performed every year. A low PGI/II ratio was defined as ≤3.

RESULTS

The PGI/II ratio was higher in non-infected patients (n=275, 4.99) than infected patients (n=498, 3.53). After H. pylori eradication, the PGI/II ratio increased to 5.81 and 5.63 after 1 and 2 years (each p<0.05). The PGI/II ratio in the non-eradication group decreased to 3.94 and 2.75 after 1 and 2 years. The PGI/II ratio in the H. pylori eradication group became similar to that of the H. pylori-negative group at 3 (4.48 vs. 4.34), 4 (4.88 vs. 4.34), and 5 years (4.89 vs. 4.23). The adjusted odds ratios for a lower PG I/II ratio in the non-eradication group compared to the eradication group were 4.78 (95% CI 2.15-10.67) after 1year and 8.13 (95% CI 2.56-25.83) after 2 years.

CONCLUSIONS

After H. pylori eradication, the PGI/II ratio increased and was similar to that of H. pylori-negative controls for up to 5 years of follow-up.

Association between Helicobacter Pylori Infection and Alopecia Areata: A Study in Iranian Population

BACKGROUND Alopecia areata is an immune mediated inflammatory hair loss, which occurs in all ethnic and age groups, and both sexes. However no significant etiology has been known for this disease. Helicobacter pylori (H. pylori) , is an organism colonized in gastric mucosa. This bacterium has been associated with certain extra-digestive dermatological conditions. The causal relationship between alopecia areata and H. pylori infection has been discussed in literature. Therefore, we conducted this study to evaluate the prevalence of H. pylori infection in patients with alopecia areata and assess the risk of this infection in patients with this disease in order to determine its potential roles in the physiopathology of this disease. METHODS Between 2014 and 2015, we prospectively studied 81 patients with alopecia areata and 81 healthy volunteers with similar age and sex. Patients without any history of H. pylori infection were included in the study and underwent urease breath test. All results were analyzed using SPSS software (version 21.0) and p value<0.05 was considered as statistically significant. RESULTS 81 patients and 81 controls with the mean age of 34.9±11.6 and 38.2±13.4 years were studied (p=0.097). 48 (59.3%) and 45 (55.6%) individuals were male, in cases and control groups respectively (p =0.634). The result of urea breath test (UBT) was positive in 43 (53.1%) patients in cases and 27 (33.3%) individuals in control group, which was significantly different (p =0.011). The risk of H. pylori infection in alopecia areata was 2.263 (95% CI: 1.199-4.273). CONCLUSION The results of our study showed significant difference between H. pylori infection in individuals with and without alopecia areata, which shows that H. pylori contamination may be effective in physiopathology of alopecia areata. Therefore these results should be tested in large multivariable cohorts and controlled trials to reach more accurate evidence in the future and to generalize this idea to larger population.

Impact of Helicobacter pylori Immunoglobulin G Levels and Atrophic Gastritis Status on Risk of Metabolic Syndrome

Background

Helicobacter pylori (HP) infection is implicated in gastric and extra-gastric diseases. While gastritis-related chronic inflammation represents a known trigger of metabolic disturbances, whether metabolic syndrome (MetS) is affected by gastritis status remains unclear. We aimed to clarify the effect of HP-related gastritis on the risk of MetS.

Materials and Methods

We retrospectively enrolled patients undergoing screening for MetS between 2014 and 2015. Investigations included HP-specific immunoglobulin G (IgG) antibody assays to detect HP infection, and serum pepsinogen assays to evaluate atrophic gastritis status. The risk of MetS was evaluated via multiple logistic regression analyses with two covariates: serum HP infection status (IgG levels) and atrophic gastritis status (two criteria were applied; pepsinogen I/II ratio < 3 or both pepsinogen I levels ≤ 70 μg/L and pepsinogen I/II ratio < 3).

Results

Of 1,044 participants, 247 (23.7%) were HP seropositive, and 62 (6.0%) had MetS. HP seronegative and seropositive patients had similar risks of MetS. On the other hand, AG (defined in terms of serum PG I/II <3) was significant risk of MetS (OR of 2.52 [95% CI 1.05–7.52]). After stratification according to HP IgG concentration, patients with low HP infection status had the lowest MetS risk (defined as an odds ratio [OR] adjusted for age, sex, smoking, drinking and physical activity status). Taking this result as a reference, patients with negative, moderate, and high HP infection status had ORs (with 95% confidence intervals [CI]) of 2.15 (1.06–4.16), 3.69 (1.12–16.7), and 4.05 (1.05–26.8).

Conclusions

HP-associated gastritis represents a risk factor for MetS. Research should determine why low and not negative HP infection status is associated with the lowest MetS risk.

Sero-prevalence and associated factors of Helicobacter pylori infection among adult patients with dyspepsia attending the gastroenterology unit in a tertiary hospital in Mwanza, Tanzania

BACKGROUND

Prevalence of H.pylori infection varies greatly between populations in different countries. This study was conducted to determine the magnitude of H.pylori among adult patients with dyspepsia attending the gastroenterology unit at Bugando medical centre.

METHODS

A cross sectional study involving 202 dyspeptic patients was conducted between June and July 2014. A Standardized data collection tool was used to collect socio-demographic characteristics. H.pylori antibodies were detected using rapid immunochromatographic tests according to manufacturer's instructions.

RESULTS

The median age of study population was 42 (IQR: 33-54). Females 105 (51.9%) formed majority of the population studied. Of 202 participants; 119 (58.9%) were from rural areas. Seroprevalence of H.pylori infection was found to be 79/202 (39.1%, 95% CI: 32.3-45.7). As the age increased the risk of having H.pylori infection also increased (OR: 1.02 95% CI: 1-1.04, P=0.02). On multivariate logistic regression analysis untreated drinking water was found to predict H.pylori seropositivity (OR: 2.33, CI: 1.09-4.96, p=0.028).

CONCLUSION

The seroprevalence of H.pylori among dyspeptic patients is high in this setting. Therefore the community in Mwanza should be educated on the use of safe drinking water in order to minimize H. pylori infections.

Serum Helicobacter pylori KatA and AhpC antibodies as novel biomarkers for gastric cancer

AIM: To investigate catalase (KatA) and alkyl hydroperoxide reductase (AhpC) antibodies of Helicobacter pylori as biomarkers for gastric cancer (GC).

METHODS: This study included 232 cases and 264 controls. Recombinant KatA and AhpC proteins were constructed and the levels of antibodies were tested by indirect enzyme-linked immunosorbent assay (ELISA). Logistic regression was applied to analyze the relationships between KatA, AhpC and GC. The χ² trend test was used to evaluate the dose-response relationships between serum KatA and AhpC antibody levels and GC. Receiver operating characteristic (ROC) curve was used to evaluate the screening accuracy of KatA and AhpC as biomarkers. Combined analysis was used to observe screening accuracy of predictors for GC.

RESULTS: In all subjects, the association between KatA and AhpC and GC risk was significant (P < 0.001) with odds ratio (OR) = 12.84 (95%CI: 7.79-21.15) and OR = 2.4 (95%CI: 1.55-3.73), respectively. KatA and AhpC antibody levels were strongly related to GC risk with a dose-dependent effect (P for trend < 0.001). The area under the ROC (AUC) for KatA was 0.806, providing a sensitivity of 66.81% and specificity of 86.36%; and the AUC for AhpC was 0.615, with a sensitivity of 75.65% and specificity of 45.49%. The AUC was 0.906 for KatA and flagella protein A (FlaA) combined analysis.

CONCLUSION: Serum KatA and AhpC antibodies are associated with GC risk and KatA may serve as a biomarker for GC. KatA/FlaA combined analysis improved screening accuracy.

DIAGNOSTIC ACCURACY OF UREA BREATH TEST FOR HELICOBACTER PYLORI INFECTION IN CHILDREN WITH DYSPEPSIA IN COMPARISON TO HISTOPATHOLOGY

ABSTRACT Background - Helicobacter pylori infection is the gram negative bacillus with the close association with chronic antral gastritis. Objective - In this study, we evaluate the accuracy of urea breath test (UBT) with carbon isotope 13 in comparison with histopathology of gastric antrum for detection of H. pylori infection in children with dyspepsia. Methods - This cross-sectional study was performed at specialized laboratory of Shiraz Gastroenterohepatology Research Center and Nemazee Hospital, Iran, during a 12-months period. This study investigated the sensitivity, specificity, and positive and negative predictive values of UBT in comparison with biopsy-based tests. We included a consecutive selection of 60 children who fulfilled Rome III criteria for dyspepsia. All children were referred for performing UBT with carbon isotope 13 (C13) as well as endoscopy. Biopsies were taken from antrum of stomach and duodenum. The pathologic diagnosis was considered as the standard test. Results - The mean age of the participants was 10.1±2.6 (range 7-17 years). From our total 60 patients, 28 (46.7%) had positive UBT results and 32 (53.3%) had negative UBT results. Pathologic report of 16 (57.1%) out of 28 patients who had positive UBT were positive for H. pylori and 12 (42.9%) ones were negative. Sensitivity and specificity of C13-UBT for detection of H. pylori infection were 76.2% and 69.2% respectively. Conclusion - Sensitivity and specificity of C13-UBT for detection of H. pylori infection were 76.2% and 69.2% respectively. Another multicenter study from our country is recommended.

The expression of IGF-1R in Helicobacter pylori-infected intestinal metaplasia and gastric cancer

Overexpression of IGF-1R has been demonstrated in gastrointestinal cancers, and its expression is reported as the result of the loss of tumor suppressors. IL-16 is involved in the pathophysiological process of chronic inflammatory diseases. The aim of this study is to determine the changes in the expression of IGF-1R in intestinal metaplasia (IM) and gastric cancer (GC) as well as the effect of Helicobacter pylori (H. pylori) and IL-16 on cell proliferation and IGF-1R expression in gastric cells. AGS cells were incubated with combinations of IL-16 and H. pylori. Gastric cell proliferation was studied by BrdU uptake. In H. pylori infected mucosa, IGF-1R was significantly higher in IM than chronic gastritis (CG), and also higher in GC than CG and IM. H. pylori significantly decreased BrdU uptake. IL-16 increased BrdU uptake and IGF-1R on AGS cells which had been decreased by H. pylori. Co-incubation with IL-16 increased the expression of IGF-1R mRNA in H. pylori infected cells. We conclude that the expression of IGF-1R in H. pylori infected gastric mucosa may indicate an early stage of carcinogenesis. The IL-16 secretion by H. pylori can be a trigger for the expression of IGF-1R, and it may also be a factor for gastric carcinogenesis.