Sociodemographic determinants of prevalence and incidence of Helicobacter pylori infection in Portuguese adults

Higher frequency of gastric neoplasia in advanced chronic liver disease patients: Impact of screening endoscopy in an intermediate-high risk country

BACKGROUND

The Baveno VII guidelines were proposed to identify which patients could safely avoid screening esophagogastroduodenoscopy (EGD) for gastroesophageal varices. We aimed to evaluate the frequency of gastric neoplasia in compensated advanced chronic liver disease (cACLD) patients who underwent EGD for screening of gastroesophageal varices (GOEV) compared to a healthy population.

METHODS

Retrospective study that enrolled all cACLD patients who underwent EGD for GOEV screening (January 2008-June 2018) in a tertiary reference center. cACLD patients were compared with asymptomatic healthy individuals who underwent EGD in a private hospital setting (April 2017-March 2018).

RESULTS

We evaluated 1845 patients (481 cACLD patients, 1364 healthy individuals). A significantly higher frequency of gastric neoplasia was observed in patients with cACLD compared to healthy individuals (4.0% vs. 1.0 %; p < 0.001). Rare histopathological subtypes (WHO Classification) accounted for 28.7 % of gastric carcinoma cases in the cACLD cohort. Seven cases of gastric neoplasia (36.8 % of gastric neoplasia cases in the cACLD patients) were diagnosed in patients who, according to the Baveno VII criteria, would have not been submitted to EGD.

CONCLUSION

We found an increased frequency of gastric neoplasia in patients with cACLD in comparison with healthy individuals. In countries with intermediate-high risk for GC, continuing to perform EGD could be beneficial.

Evaluation of Antral Biopsies Obtained in Endoscopically Normal Esophagogastroduodenoscopy: A Retrospective Cohort Study

BACKGROUND

The requirement for routine biopsy sampling in esophagogastroduodenoscopy (EGD) with normal endoscopic findings is a subject of debate. In this study, patients who had normal endoscopic findings in EGD and underwent biopsy sampling were retrospectively analyzed.

METHODS

This single-center retrospective cohort study included 671 patients who underwent EGD between 2021 and 2023 in the Sisli Hamidiye Etfal Training and Research Hospital Surgical Endoscopy Unit. All patients had normal endoscopic findings and a sampling biopsy was performed on all patients included. Patients were evaluated based on demographic and clinicopathologic findings. This study was registered to ClinicalTrials.gov (NCT06269380).

RESULTS

Two hundred sixty patients (38.7%) have abnormal histopathologic findings. Helicobacter pylori positivity was detected in 200 (29.8%) patients. Intestinal metaplasia (IM) was present in 80 of 260 patients (30.8%). The frequency of IM was higher in older age groups and cases with mild gastritis ( P <0.001). The frequency and severity of gastritis were associated with increased H. pylori positivity and density ( P <0.001).

CONCLUSIONS

The biopsy sampling may contribute to the diagnosis and treatment process in cases where normal endoscopic findings are observed during EGD.

Total worker health® based Helicobacter pylori public health prevention strategy

Purpose of review

This review aims to explore the public health approach for Helicobacter pylori Infection Prevention within the Total Worker Health (TWH) framework strategy.

Recent findings

The review identifies certain occupations considered high-risk groups for H. pylori infection. It underscores primary, secondary, and tertiary public health preventive measures align with the TWH approach. Within this framework, the role of raising awareness, emphasizing infection control, worker hygiene, risk assessment, and ensuring healthcare accessibility is emphasized. The importance of early detection, treatment, eradication, and a TWH approach emerges as a central theme. The TWH approach offers a holistic perspective, intertwining occupation-related health risks with overall health and well being.

Summary

Adopting the TWH approach, coupled with household-based infection control and eradication strategies, can significantly reduce H. pylori prevalence, fostering a healthier workforce and diminishing long-term healthcare costs. The review underscores the importance of recognizing H. pylori as an occupational disease. It calls for further research into the "one-health" perspective on H. pylori transmission dynamics.

Helicobacter pylori infection in humans and phytotherapy, probiotics, and emerging therapeutic interventions: a review

The global prevalence of Helicobacter pylori (H. pylori) infection remains high, indicating a persistent presence of this pathogenic bacterium capable of infecting humans. This review summarizes the population demographics, transmission routes, as well as conventional and novel therapeutic approaches for H. pylori infection. The prevalence of H. pylori infection exceeds 30% in numerous countries worldwide and can be transmitted through interpersonal and zoonotic routes. Cytotoxin-related gene A (CagA) and vacuolar cytotoxin A (VacA) are the main virulence factors of H. pylori, contributing to its steep global infection rate. Preventative measures should be taken from people's living habits and dietary factors to reduce H. pylori infection. Phytotherapy, probiotics therapies and some emerging therapies have emerged as alternative treatments for H. pylori infection, addressing the issue of elevated antibiotic resistance rates. Plant extracts primarily target urease activity and adhesion activity to treat H. pylori, while probiotics prevent H. pylori infection through both immune and non-immune pathways. In the future, the primary research focus will be on combining multiple treatment methods to effectively eradicate H. pylori infection.

Prevalence of Helicobacter pylori genotypes: cagA, vacA (m1), vacA (s1), babA2, dupA, iceA1, oipA and their association with gastrointestinal diseases. A cross-sectional study in Quito-Ecuador

BACKGROUND

The most prevalent stomach infection in the world is caused by Helicobacter pylori (H. pylori). Several pathogenicity genes, including cagA, vacA, babA2, dupA, iceA, and oipA, are associated with an increased risk of gastrointestinal disease such as peptic ulcer and stomach cancer. This research aims to determine the prevalence of different H. pylori genotypes and correlate their risk in the development of gastrointestinal diseases in the Ecuadorian population.

METHODS

A cross-sectional research of 225 patients at the Calderón Hospital in Quito, Ecuador, was conducted. End point PCRs were run to determine the presence of 16S rRNA, cagA, vacA (m1), vacA (s1), babA2, dupA, iceA1, and oipA virulence genes. Chi-square test, odds ratios (OR) and 95% confidence intervals (CI) were utilized for the statistical analysis.

RESULTS

H. pylori infection was present in 62.7% of people. Peptic ulcers were seen in 22.2% and malignant lesions in 3.6% of patients. Genes oipA (93.6%), vacA (s1) (70.9%), and babA2 (70.2%) were the most prevalent. cagA/vacA (s1m1) and cagA/oipA (s1m1) combinations were found in 31.2% and 22.7% of the cases, respectively. Acute inflammation has a significant correlation with the genes cagA (OR = 4.96 95% CI: 1.1-22.41), babA2 (OR = 2.78 95% CI: 1.06-7.3), and the cagA/oipA combination (OR = 4.78, 95% CI: 1.06-21.62). Follicular hyperplasia was associated with iceA1 (OR = 3.13; 95% CI: 1.2-8.16), babA2 (OR = 2.56; 95% CI: 1.14-5.77), cagA (OR = 2.19; 95% CI: 1.06-4.52), and the cagA/oipA combination (OR = 2.32, 95% CI: 1.12-4.84). The vacA (m1) and vacA (s1m1) genes were associated with gastric intestinal metaplasia (OR = 2.71 95% CI: 1.17-6.29) (OR = 2.33 95% CI: 1.03-5.24). Finally, we showed that cagA/vacA (s1m1) gene combination increased the risk of duodenal ulcer development (OR = 2.89, 95% CI 1.10-7.58).

CONCLUSION

This study makes a significant contribution by offering genotypic information regarding H. pylori infection. The presence of several H. pylori genes was associated with the onset of gastrointestinal illness in the Ecuadorian population.

Single-capsule bismuth-based quadruple therapy as a rescue therapy for Helicobacter pylori eradication

INTRODUCTION

Helicobacter pylori (H. pylori) infection is highly prevalent in Portugal and its eradication is formally recommended. However, the indiscriminate use of antimicrobials has led to a drastic rise in antibiotic resistance, with the failure of traditional eradication schemes. A single-capsule bismuth-based quadruple therapy became recently available in Portugal. This study aims to evaluate the efficacy and safety of a bismuth-based quadruple therapy as a second-line or rescue therapy.

PATIENTS AND METHODS

This was a multicentric study. All consecutive patients that were treated with bismuth-based quadruple therapy, as second-line or salvage treatment between July 2017 and April 2019 were enrolled. Their medical records were reviewed and clinical and laboratorial parameters, as well as data on treatment efficacy and adverse events were retrieved. Patients were also contacted by phone after treatment to confirm compliance, adverse events, and global satisfaction with this specific therapy.

RESULTS

A total of 151 subjects were included (female-68.9%; mean age-56 ± 13.5 years). Patients were previously submitted to 212 eradication schemes (Median-1; 1-5; IQR:4): 33.5% triple clarithromycin-based, 25% sequential, 7.5% concomitant, 5.2% others, and in 28.8% it was not possible to know the previous eradication scheme(s) followed by the patient. The PPI of choice was esomeprazole (39.7%), followed by omeprazole (27.8%). Compliance was achieved in 93.4% and the overall eradication rate was 90.1% (95% CI: 84.6-94.2). Treatment-related adverse effects were experienced by 63 patients (41.7%; 95% CI: 34-49.7), being mild in 29, moderate in 19, and severe in 15. The main drawbacks of the treatment, from the patient's perspective, were the high price (47%) and the adverse effects (16.6%). Failure to eradicate H. pylori was correlated with the following: previous rifabutin-based scheme (0 vs. 100%; p = 0.010) and a higher number of previous treatment schemes (1.5 ± 0.7 vs. 2.3 ± 1.2; p < 0.001).

CONCLUSION

In this South-European country a single-capsule bismuth-based quadruple therapy is an excellent option as a second-line or rescue therapy, with acceptable compliance and side effects.

Multicentric Study to Assess Helicobacter pylori Incidence, Patient Reported Adverse Events, Compliance and Effectiveness, in Real-World Setting

Helicobacter pylori ( H. pylori) plays an important role in chronic gastritis and globally it is estimated to be present in half of the world's population. In Portugal, prevalence reaches 85% and its eradication is recommended using quadruple antibiotic therapy, with or without bismuth. We intended to characterize the prescribed treatments evaluating effectiveness, adverse outcomes and compliance in a real-world setting in a primary care unit. A prospective multicenter observational cohort study was developed in five primary care units of Braga, Portugal. Patients diagnosed with H. pylori infection from August 2021 to January 2022 were included. Data were collected by interview (3 weeks after treatment) and review of medical records. Comparison between two groups of treatment and multivariable analysis was conducted. We estimated 13.4 cases per 1000 adults/year from 185 diagnoses. Therapy with bismuth was the most prescribed (83.8%) with a 96.7% eradication rate. There were no significant differences between treatments. Adverse events were reported in 73.8% of inquiries and female patients were associated with higher reports of nausea (p = 0.03) and metallic taste (p = 0.02). Both eradication schemes were effective and secure. The higher rate of adverse outcomes should be validated but it could influence the debate concerning treating all patients, especially in low gastric cancer-prevalence regions.

Prevalence of Helicobacter pylori infection among asymptomatic children in southeastern Brazil: a cross-sectional study

BACKGROUND

The prevalence of Helico bacter pylori (H. pylori) infection is decreasing worldwide, but is still high in developing countries. We previously observed an H. pylori infection rate of 52% among children and adolescents with chronic non-ulcer dyspepsia.

OBJECTIVE

To investigate the prevalence of H. pylori infection among asymptomatic children living in a single region and to evaluate the risk factors for this infection.

DESIGN AND SETTING

Cross-sectional study in which 161 children aged 5-13 years (mean age 7.8 years), at a public school in Botucatu, state of São Paulo, southeastern Brazil, were assessed.

METHOD

The children's H. pylori infection status was determined through the urea breath test and the risk factors for acquisition of the infection were determined based on a sociodemographic questionnaire.

RESULTS

The overall prevalence of H. pylori infection was 20.5%: 18.7% among females and 22.2% among males. The results from the sociodemographic survey did not differ between children with and without H. pylori infection. 30.9% of the children had previous records of upper gastrointestinal symptoms, which consisted of H. pylori infection in only 26.5% of these cases. Family histories of gastritis and peptic ulcer disease were found in relation to 50% and 32.3% of the children with H. pylori infection respectively.

CONCLUSION

The prevalence of H. pylori infection among asymptomatic children in southeastern Brazil is lower than that recorded among symptomatic children in the same region and similar to the prevalence of H. pylori infection observed in developed countries.

Investigation the levels of endotoxin and 8-hydroxy-2'-deoxyguanosine in sera of patients with Helicobacter pylori-positive peptic ulcer

BACKGROUND

Peptic ulcer is considered an important public health problem and generally associated with complicated conditions such as bleeding and perforation. The aim of this study is to reflect the rate of oxidative damage in the body among dyspeptic patients with Helicobacter pylori-positive peptic ulcer by measuring 8-hydroxy-2'-deoxyguanosine (8-OHdG) level in serum samples and its association with the level of bacterial endotoxin.

METHODS

Patients referred to Harran University Gastroenterology Outpatient Clinic with dyspeptic complaints were enrolled in this study. According to gastrointestinal endoscopy findings, 43 dyspeptic patients with H pylori-positive peptic ulcer patients and 43 healthy volunteers were included in this study. Infection with H pylori was diagnosed by H pylori urea breath and stool antigen tests. Serum 8-OHdG and endotoxins were measured by ELISA.

RESULTS

A total of 43 dyspeptic patients with peptic ulcer (13 women and 30 men) and 43 healthy individuals (16 women and 27 men) were enrolled in the study. In biopsies taken endoscopically, H pylori severity was mild in 19 patients (43.9%), moderate in 21 patients (48.5%) and severe in 3 patients (7.6%). 8-OHdG was compared with the healthy and patient group. It was observed that there was a statistically significant difference (P < .01). In addition, a weak correlation was found between OHdG and bacterial endotoxin.

CONCLUSION

Serum 8-OHdG and endotoxin levels are only weakly associated implying that they reflect specific aspects of oxidative damage. Helicobacter pylori and its endotoxin have a significant role in peptic ulcer pathogenesis. The detection of serum 8-OHdG in dyspeptic patients may be used as a biomarker for the presence of peptic ulcers.

Guidelines in Gastroenterology: Careful Interpretation Is Essential

Introduction

Clinical practice guidelines (CPG) contain recommendations that aim to guide physicians in the diagnosis of and therapeutic approach toward patients affected by gastrointestinal (GI) pathologies. These CPG systematically combine scientific evidence and clinical judgment, culminating in recommendations that have been shown to improve patient care.

Material and Methods

European and North American guidelines published in the area of gastroenterology in 2018 and 2019 were considered for inclusion. To standardize the results, only guidelines that used GRADE as an evidence system were included. Thus, in the end, 1,233 recommendations from 29 guidelines published between 2018 and 2019 were analyzed.

Results

Of the 1,233 recommendations collected, 324 (26.3%) had a low level of evidence and 127 (10.3%) had a very low level of evidence, indicating little evidence or expert opinion. Of the 29 publications analyzed, 14 (48.3%) did not present any recommendation with a high level of evidence. Regarding the 1,233 individual recommendations expressed in these 29 publications, only 336 (27.25%) assumed a high level of evidence, with 277 (82.44%) referring to liver pathology. Of the recommendations evaluated, 77 were from North American societies and the remaining 1,156 were European recommendations. In relation to the first group, only 3 (3.9%) had a high level of evidence belonging to the Guidelines for Sedation and Anesthesia in GI Endoscopy.

Conclusions

More than 25% of all recommendations currently accepted to guide patients with gastroenterological disorders are based on low-quality evidence or expert opinion. Thus, these documents should guide our performance, but clinical sense and multidisciplinarity must not be overlooked in dubious cases and with weak scientific evidence. Research should focus on the development of randomized controlled trials and systematic reviews to improve the evidence supporting the guidelines that guide clinical practice.

An Overview of Helicobacter pylori Infection

Helicobacter pylori (H. pylori) represents one of the most widespread bacterial infections globally. Infection causes chronic gastritis and increases the risk of peptic ulcer disease, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. The pioneering discovery of H. pylori by Marshall and Warren in the early 1980s has initiated fervent research into H. pylori as a pathogen ever since. This chapter aims to provide an overview of our understanding of H. pylori infection and its management, with a focus on current options for diagnosis, the challenges associated with H. pylori eradication, and the need for alternative therapeutic strategies based on furthering our understanding of host: H. pylori interactions.

Procyanidin-Rich Extract from Grape Seeds as a Putative Tool against Helicobacter pylori

Strains of Helicobacter pylori (H. pylori) resistant to various antibiotics have increased in recent years. In this context, the search for new therapeutic approaches is crucial. The aim of the present study was to demonstrate the antibacterial activity of a procyanidin-rich extract obtained from food-grade winery grape seeds against 14 H. pylori strains and elucidate its phenolic composition. Ten strains (71.4%) showed resistance to at least some of the tested antibiotics, while four isolates (28.6%) were susceptible to all antibiotics. Resistance to more than one class of antibiotics was observed in six strains (42.9%). The extract was able to inhibit the growth of all H. pylori strains in a range of a minimum inhibitory concentration (MIC) from 0.015 mg/mL to 0.125 mg/mL, confirming also the existence of a strain-dependent effect. The phenolic composition determined by reverse phase high pressure liquid chromatography, photodiode array, and mass spectrometry detection (RP-HPLC-PAD-MS) analysis revealed the presence of 43 individual compounds and allowed the quantification of 41 of them, including seven procyanidin tetramers, seven procyanidin pentamers, and six galloylated procyanidin dimers, trimers, and tetramers. The extract was composed mainly by catechin and procyanidin oligomers with a total amount of 5801 mg/100 g, which represent 92% of the total individual phenolic content. Among them, the most abundant were catechins (2047 mg/100 g), followed by procyanidin dimers (1550 mg/100 g), trimers (1176 mg/100 g), tetramers (436 mg/100 g), and pentamers (296 mg/100 g) that represent 35, 27, 20, 8, and 5%, respectively of the total flavanol constituents. The composition profile information may help to improve the production process of useful antibacterial extracts against H. pylori.

Where to Biopsy to Detect Helicobacter pylori and How Many Biopsies Are Needed to Detect Antibiotic Resistance in a Human Stomach

This study aims to determine the gastric distribution, density, and diversity of Helicobacter pylori infection. Subtotal resection of the stomachs of three H. pylori-infected and asymptomatic obese patients were collected after a sleeve gastrectomy. Distribution and density of H. pylori were determined using culture and RT-PCR on multiple gastric sites (88, 176, and 101 biopsies per patient). Diversity of H. pylori strains was studied using antibiotic susceptibility testing, random amplified polymorphism DNA (RAPD) typing and cagA gene detection on single-colony isolates (44, 96, and 49 isolates per patient). H. pylori was detected in nearly all analyzed sites (354/365 biopsies, 97%). Antral density was higher in one patient only. The three stomachs were almost exclusively infected by an antibiotic-susceptible strain. One clarithromycin-resistant isolate in one biopsy was detected in two stomachs (1/44 and 1/49 isolates), while in the third one, eight (8/96 isolates) metronidazole-resistant isolates were detected. DNA typing showed infection with cagA-negative strains for one patient, cagA-positive strains for a second patient and the third patient was infected with two different strains of distinct cagA genotypes. Infection with H. pylori is shown to spread to the whole surface of the stomach, but a possibility of minor sub-population of antibiotic-resistant clones, undetectable in routine practice.

Helicobacter pylori patient isolates from South Africa and Nigeria differ in virulence factor pathogenicity profile and associated gastric disease outcome

Helicobacter pylori is a gram-negative, spiral-shaped bacterial pathogen and the causative agent for gastritis, peptic ulcer disease and classified as a WHO class I carcinogen. While the prevalence of H. pylori infections in Africa is among the highest in the world, the incidence of gastric cancer is comparably low. Little is known about other symptoms related to the H. pylori infection in Africa and the association with certain phenotypes of bacterial virulence. We established a network of study sites in Nigeria (NG) and South Africa (ZA) to gain an overview on the epidemiological situation. In total 220 isolates from 114 patients were analyzed and 118 different patient isolates examined for the presence of the virulence factors cagA, vacA, dupA, their phylogenetic origin and their resistance against the commonly used antibiotics amoxicillin, clarithromycin, metronidazole and tetracycline. We report that H. pylori isolates from Nigeria and South Africa differ significantly in their phylogenetic profiles and in their expression of virulence factors. VacA mosaicism is intensive, resulting in m1-m2 vacA chimeras and frequent s1m1 and s1m2 vacA subtypes in hpAfrica2 strains. Gastric lesions were diagnosed more frequent in Nigerian versus South African patients and H. pylori isolates that are resistant against one or multiple antibiotics occur frequently in both countries.

Helicobacter pylori-related risk predictors of gastric cancer: The latest models, challenges, and future prospects

Helicobacter pylori is known as an important determinant of preneoplastic lesions or gastric cancer (GC) risk. The bacterial genotypes may determine the clinical outcomes. However, the evidence for these associations has varied between and within continents, and the actual effect of each gene and corresponding allelic variants are still debatable. In recent years, two new models have been proposed to predict the risk of GC; the phylogeographic origin of H. pylori strains and a disrupted co-evolution between H. pylori and its human host, which potentially explain the geographic differences in the risk of H. pylori-related cancer. However, these models and earlier ones based on putative virulence factors of the bacterium may not fully justify differences in the incidence of GC, reflecting that new theories should be developed and examined. Notably, the new findings also support the role of ancestry-specific germline alteration in contributing to the ethnic/population differences in cancer risk. Moreover the high and low incidence areas of GC have shown differences in transmission ecology, largely affecting the composition of H. pylori populations. As a new hypothesis, it is proposed that any high-risk population may have its own specific risk loci (or variants) as well as new H. pylori strains with national/maybe regional gene pools that should be considered. The latter is seen in the Americas where the rapid evolution of distinct H. pylori subpopulations has been occurred. It is therefore proposed that the deep sequencing of both H. pylori and its human host is simultaneously performed in GC patients and age-sex-matched controls from high-risk areas. The expression and functional activities of the identified new determinants of GC must then be assessed and matched with human and pathogen ancestry, because some of risk loci are ancestry-specific. In addition, potential study-level covariates and moderator variables (eg physical conditions, life styles, gastric microbiome, etc) linked to causal relationships, and their impact, should be recognized and controlled.

Helicobacter pylori seroprevalence in Spain: influence of adult and childhood sociodemographic factors

Helicobacter pylori (H. pylori) chronic infection causes severe digestive diseases, including gastric cancer, and certain strains entail a higher risk. Risk factors for this infection are still not fully understood. The aim of this study was to describe the association of adult and childhood sociodemographic factors with the seroprevalence of H. pylori, and with CagA and VacA antigen-specific seropositivity among H. pylori-seropositive individuals in the Spanish adult population. Serum antibody reactivity to H. pylori proteins was evaluated using multiplex serology in 2555 population-based controls enrolled in the MCC-Spain study, a multicase-control study recruiting participants from 2008 to 2013 in different areas of Spain. H. pylori seroprevalence was defined as seropositivity against at least four bacterial proteins. Information on sociodemographics, lifestyles, and environmental exposures was collected through personal interviews. Prevalence ratios and 95% confidence intervals were estimated using Poisson regression models to assess the association of lifetime sociodemographic factors with H. pylori seroprevalence and with seropositivity for CagA and VacA. H. pylori seroprevalence was 87.2%. Seropositivity was statistically significantly higher in men, increased with age, BMI, and number of siblings, and decreased with education and socioeconomic family level at birth. Among H. pylori-seropositive individuals, seropositivity was 53.3% for CagA, 61.4% for VacA, and 38.8% for both CagA and VacA. Ever smokers had lower seroprevalence for CagA and VacA than never smokers. H. pylori seroprevalence among this Spanish adult population was high and one third of the population was seropositive for two well-known markers of gastric cancer risk: CagA and VacA. Sex, age, education, and BMI were associated with H. pylori seroprevalence.

Epidemiology and role of Helicobacter pylori virulence factors in gastric cancer carcinogenesis

Infection with Helicobacter pylori is associated with the development of gastric cancer. Although the prevalence of gastric cancer has declined throughout years due to improvement in early screening strategy, mortality due to gastric cancer has not changed. Incidence and mortality due to gastric cancer are higher in developing countries as compared to developed countries. Diagnosis and prognosis of gastric cancer are still poor with patients usually diagnosed with cancer at an advanced stage. Eradication of H. pylori is pertinent for the prevention of gastric cancer. However, the rise in antimicrobial resistance among H. pylori isolates has complicated the prevention strategy. H. pylori express multiple virulence factors for survival in the hostile acid gastric environment. The expression of oncogenic protein cytotoxin-associated gene A (CagA), vacuolating cytotoxin A (VacA), and outer inflammatory protein is essential for H. pylori to exert pathogenesis towards the host. Interestingly, <3% of H. pylori-infected subjects develop gastric cancer, suggesting a unique way of interaction between the host's immune response and H. pylori virulence factors. This article is aimed to review the epidemiology and role of H. pylori in gastric carcinogenesis. A better understanding of the interaction between H. pylori virulence factors and host is required for better gastric cancer prevention.

A comparative proteomic approach using metabolic pathways for the identification of potential drug targets against Helicobacter pylori

BACKGROUND

Helicobacter pylori is the most highlighted pathogen across the globe especially in developing countries. Severe gastric problems like ulcers, cancers are associated with H. pylori and its prevalence is widespread. Evolution in the genome and cross-resistance with different antibiotics are the major reason of its survival and pandemic resistance against current regimens.

OBJECTIVES

To prioritize potential drug target against H. pylori by comparing metabolic pathways of its available strains.

METHODS

We used various computational tools to extract metabolic sets of all available (61) strains of H. pylori and performed pan genomics and subtractive genomics analysis to prioritize potential drug target. Additionally, the protein interaction and detailed structure-based studies were performed for further characterization of protein.

RESULTS

We found 41 strains showing similar set of metabolic pathways. However, 19 strains were found with unique set of metabolic pathways. The metabolic set of these 19 strains revealed 83 unique proteins and BLAST against human proteome further funneled them to 38 non-homologous proteins. The druggability and essentiality testing further converged our findings to a single unique protein as a potential drug target against H. pylori.

CONCLUSION

We prioritized one protein-based drug target which upon subject to applied protocol was found as close homolog of the Saccharopine dehydrogenase. Our study has opened further avenues of research regarding the discovery of new drug targets against H. pylori.

Previous Helicobacter pylori infection-induced atrophic gastritis: A distinct disease entity in an understudied population without a history of eradication

Individuals with chronic atrophic gastritis who are negative for active H. pylori infection with no history of eradication therapy have been identified in clinical practice. By excluding false-negative and autoimmune gastritis cases, it can be surmised that most of these patients have experienced unintentional eradication of H. pylori after antibiotic treatment for other infectious disease, unreported successful eradication, or H. pylori that spontaneously disappeared. These patients are considered to have previous H. pylori infection-induced atrophic gastritis. In this work, we define these cases based on the following criteria: absence of previous H. pylori eradication; atrophic changes on endoscopy or histologic confirmation of glandular atrophy; negative for a current H. pylori infection diagnosed in the absence of proton-pump inhibitors or antibiotics; and absence of localized corpus atrophy, positivity for autoantibodies, or characteristic histologic findings suggestive of autoimmune gastritis. The risk of developing gastric cancer depends on the atrophic grade. The reported rate of developing gastric cancer is 0.31%-0.62% per year for successfully eradicated severely atrophic cases (pathophysiologically equal to unintentionally eradicated cases and unreported eradicated cases), and 0.53%-0.87% per year for spontaneously resolved cases due to severe atrophy. Therefore, for previous H. pylori infection-induced atrophic gastritis cases, we recommend endoscopic surveillance every 3 years for high-risk patients, including those with endoscopically severe atrophy or intestinal metaplasia. Because of the difficulty involved in the endoscopic diagnosis of gastric cancer in cases of previous infection, appropriate monitoring of the high-risk subgroup of this understudied population is especially important.

Esophagogastroduodenoscopy Findings in Patients on the Waiting List for Bariatric Surgery

BACKGROUND

Bariatric surgery (BS) is one of the most effective approaches to weight loss. Performing esophagogastroduodenoscopy (EGD) prior to BS is controversial but allows the detection and treatment of mucosal lesions that may affect surgical decision and type of surgery.

AIM

The aim of this study was to identify the frequency of gastric lesions and Helicobacter pylori (Hp) infection in a group of asymptomatic patients on the waiting list for BS.

METHODS

This is a retrospective descriptive study including patients undergoing EGD before BS.

RESULTS

A total of 360 patients were included with a mean age of 42.1 ± 10.8 years, 319 (88.6%) were females, with a mean body mass index of 42.8 ± 5.44 kg/m2. Regarding endoscopic findings, 25.6% presented no endoscopic lesions, 61.6% presented hyperemic gastropathy, 11.4% erosive gastropathy, 1.1% gastric polyp, and 0.3% gastric ulcer. Histologically, no changes were observed in 20.8% of the patients, 239 (66.4%) presented with superficial gastritis, 11.7% (n = 42) had chronic atrophic gastritis and intestinal metaplasia (n = 34 in the antrum, n = 1 in the body, and n = 7 in both the antrum and the body), and 1.7% (n = 6) had low-grade dysplasia. Hp was positive in 251 (69.7%) patients. We found that patients with metaplasia or dysplasia were more frequently submitted to surgical techniques that did not exclude the stomach (55.8 vs. 16.4%, p < 0.001).

CONCLUSION

EGD with histological analysis plays an important role in the pre-surgical evaluation in BS, with a high rate of pathological findings in asymptomatic patients. These findings may have an impact on the long-term management and outcomes of these patients.

Review of current diagnostic methods and advances in Helicobacter pylori diagnostics in the era of next generation sequencing

Helicobacter pylori (H. pylori) infection is highly prevalent in the human population and may lead to severe gastrointestinal pathology including gastric and duodenal ulcers, mucosa associated tissue lymphoma and gastric adenocarcinoma. In recent years, an alarming increase in antimicrobial resistance and subsequently failing empiric H. pylori eradication therapies have been noted worldwide, also in many European countries. Therefore, rapid and accurate determination of H. pylori’s antibiotic susceptibility prior to the administration of eradication regimens becomes ever more important. Traditionally, detection of H. pylori and its antimicrobial resistance is done by culture and phenotypic drug susceptibility testing that are cumbersome with a long turn-around-time. Recent advances in diagnostics provide new tools, like real-time polymerase chain reaction (PCR) and line probe assays, to diagnose H. pylori infection and antimicrobial resistance to certain antibiotics, directly from clinical specimens. Moreover, high-throughput whole genome sequencing technologies allow the rapid analysis of the pathogen’s genome, thereby allowing identification of resistance mutations and associated antibiotic resistance. In the first part of this review, we will give an overview on currently available diagnostic methods for detection of H. pylori and its drug resistance and their implementation in H. pylori management. The second part of the review focusses on the use of next generation sequencing technology in H. pylori research. To this end, we conducted a literature search for original research articles in English using the terms “Helicobacter”, “transcriptomic”, “transcriptome”, “next generation sequencing” and “whole genome sequencing”. This review is aimed to bridge the gap between current diagnostic practice (histology, rapid urease test, H. pylori culture, PCR and line probe assays) and new sequencing technologies and their potential implementation in diagnostic laboratory settings in order to complement the currently recommended H. pylori management guidelines and subsequently improve public health.

Prevalence and genotyping of Helicobacter pylori in endoscopic biopsy samples from a Chinese population

Background:

Helicobacter pylori inhabit the gastric mucosa of humans and are associated with several gastrointestinal diseases which include gastric cancer, peptic ulcer, chronic gastritis and gastric mucosa-associated lymphoid tissue lymphoma. Helicobacter pylori exhibit a high degree of genetic variability and are associated with its epidemiological, pathological characteristics and dynamics of transmission. The objective of the study was to determine the prevalence and genetic heterogeneity of H. pylori isolated from endoscopic biopsy samples from a Chinese population.

Methods:

Gastric biopsy samples from 86 patients (males, 55; females, 35) who presented to the endoscopic section for various gastrointestinal abnormalities were collected. The samples were subjected to a real-time polymerase chain reaction (PCR) and microbial culture for the isolation of H. pylori. Further, the isolates were subjected to randomly amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) analysis.

Results:

Of the 86 gastric biopsy samples, 61 (70.9%) samples were positive for rapid urease test and 37 (43%) samples (28 from male and nine from female) grew H. pylori. Among the biopsy samples subjected to real-time PCR, 39 (45.3%) samples were found to be positive for H. pylori. The RAPD analysis yielded 15 different patterns (four to 17 different sized fragments per strain). The phylogenetic analysis of RAPD yielded 22 clusters at a similarity level ranging from 63% to 100%. RFLP analysis yielded nine different patterns (two to six different sized fragments per strain). Two major restriction patterns were identified, of which 14 (37.8%) strains forms the most common pattern (genotype I) followed by five (13.5%, genotype II) strains with an intra-strain similarity of 100%.

Conclusions:

The overall prevalence of H. pylori was 45.3%. Despite reports on the declining trend in the prevalence of H. pylori infections, our prevalence rate was still higher than those reported from other developed countries. However, further studies involving a large sample size and covering more regions of China is highly warranted.

Study of rdxA and frxA genes mutations in metronidazole-resistant and -susceptible Helicobacter pylori clinical isolates from the central region of Portugal

OBJECTIVES

Helicobacter pylori is one of the most prevalent global pathogens colonising an estimated 50% of the world's population. Although metronidazole (MTZ) is an important antibiotic playing a relevant role in various H. pylori eradication therapies, its frequent consumption results in an increased frequency of resistance with a consequent negative impact on treatment efficacy. Mutations on genes encoding NADPH nitroreductases, commonly known as rdxA gene (oxygen-insensitive) and frxA gene (flavinreductase) have been associated to H. pylori resistance to metrodinazole. The aim of this study was to evaluate the mutation profile of rdxA and frxA genes in a population of 38 H. pylori isolates with phenotypic patterns of susceptibility and resistance to this antibiotic.

METHODS

Touchdown PCR with the purpose of amplifying rdxA and frxA genes in one PCR was used. Sequence data were made by pair-wise sequence alignment and were examined in terms of codons, and comparison was achieved regarding amino acids.

RESULTS

Although repeated mutations occurred in positions 118, 131, 172 and 183 of rdxA and in positions 72, 73, 110, 126 and 193 of frxA, it must be highlighted that the mutations are widespread along these two genes in this population. Furthermore, six MTZ-resistant isolates did not present any mutation in the frxA gene.

CONCLUSIONS

This work appears to confirm that mutations in rdxA and frxA alone are unable to explain MTZ resistance in H. pylori isolates and therefore additional mechanisms may exist and should be investigated.

Current and Future Treatment of Helicobacter pylori Infections

Helicobacter pylori is one of the most common human pathogens and it has been estimated that about 50% of the world's population is currently infected. The present consensus is that, unless there are compelling reasons, all H. pylori infections should be cured. Since the 1990s, different national and international guidelines for the management of H. pylori-related diseases have been published and periodically updated regarding indications for treatment, diagnostic procedures, and preferred treatment regimens. Most guidelines provide sophisticated meta-analyses examining the outcome of different regimens done in regions with variable, often high rates of resistance to antibiotics, for which the prevalence and effects of resistance was often ignored. Although successful antimicrobial therapy must be susceptibility-based, increasing antimicrobial resistance and general unavailability of susceptibility testing have required clinicians to generally rely on empiric regimens. Antibiotics resistance of H. pylori has reached alarming high levels worldwide, which has an effect to efficacy of treatment. The recommendations should provide regimes for multi-resistant infections or for those where susceptibility testing is unavailable or refused. The first rule is to use only proven locally effective therapies. Because of patient intolerances, drug allergies, and local experiences, the clinicians should have at least two options for first-line therapy. As with any antimicrobial therapy, a thorough review of prior antibiotic use is invaluable to identify the presence of probably resistance. The second key is patient education regarding potential and expected side-effects and the importance of completing the course of antibiotics. We also review here triple therapies, sequential-concomitant, hybrid therapies, bismuth therapies, dual therapy, vonoprazan, modern antibiotic treatments, probiotics and vaccination.

Helicobacter pylori antimicrobial resistance in a pediatric population

BACKGROUND

The increasing prevalence of Helicobacter pylori (H. pylori) antimicrobial resistance, primarily for clarithromycin decreases the success of treatment. The aim of this study is to determine the local pattern of first-line antimicrobials resistance and the eradication rate.

MATERIAL AND METHODS

Prospective cohort study of H. pylori infected patients (positive histological or cultural exams) treated at Centro Materno-Infantil do Norte from January of 2013 to October of 2017. Susceptibility to 4 antibiotics: amoxicilin, metronidazole, clarithromycin, and levofloxacin were analyzed by E-test (phenotypic resistance). The E-test was chosen because it is simple and cost-effective for routine susceptibility testing. Point mutations that confer clarithromycin resistance were surveyed (genotypic resistance). Eradication of H. pylori infection was defined by a negative urea breath test or fecal antigen 6-8 weeks after the end of treatment.

RESULTS

Of a total of 74 H. pylori infected patients, 16 were excluded because they had previous H. pylori treatment or severe systemic disease. Median age of infection cases was 15 years (3-17 years). Eradication regimen used in all patients combined the use of 3 antibiotics (amoxicillin and metronidazole or clarithromycin) and proton pump inibhitor for 14 days and was tailored according antimicrobial susceptibility. 79.5% of the patients completed the treatment. The resistance rate for metronidazole and clarithromycin was 3.3% and 23.3%, respectively. There was no resistance for amoxicilin and levofloxacin. The rate of genotypic resistance to clarithromycin was 37.2%. The eradication rate was 97.8%.

CONCLUSIONS

The authors found a high resistance rate of H. pylori for clarithromycin in this northern portuguese pediatric center. This factor should determine a change in local current treatment, contraindicating the use of clarithromycin as a first-line treatment for H. pylori infection in children. The high eradication rate maybe explained for the eradication treatment tailored according antimicrobial susceptibility.

Helicobacter pylori antibiotic resistance in Portugal: Systematic review and meta-analysis

BACKGROUND

Portugal presents both a high prevalence of Helicobacter pylori (Hp) infection and a high prevalence of antibiotic resistance. However, conclusive data on its magnitude are lacking. We aimed at summarizing the existing data.

MATERIALS AND METHODS

A systematic review was conducted after searching in two databases (PubMed and SciELO). Meta-analysis was performed, and comparison of resistance rates between children and adults and by type of resistance (primary and secondary) was made.

RESULTS

Eight cross-sectional studies assessing Hp resistance to antibiotics were included. Overall resistance rates were as follows: clarithromycin (CLA) 42% (95% CI: 30-54), metronidazole (MTZ) 25% (95% CI: 15-38), ciprofloxacin (CIP) 9% (95% CI: 3-18), levofloxacin (LVX) 18% (95% CI: 2-42), tetracycline (TTC) 0.2% (95% CI: 0-1), and amoxicillin (AMX) 0.1% (95% CI: 0-0.2). Multidrug resistance was also an important problem, with the following global resistance rates: CLA plus MTZ of 10% (adults 20% (95% CI: 15-26) vs children 6% (95% CI: 4-9)) and CLA plus CIP of 2% (primary resistance in children's group). High secondary resistance rates were found for all antibiotics. Resistance was higher among adults for all antibiotics, except CLA that had high resistance levels both among adults and children (42% 95% CI: 14-71 and 40% 95% CI: 33-47).

CONCLUSIONS

Hp resistance to the most widely used antibiotics is high in Portugal. Accordingly, our results suggest that the best therapeutic strategy for Hp in Portugal may be quadruple therapy with bismuth for adults and triple therapy including AMX plus MTZ or bismuth-based therapy for children.

Helicobacter pylori associated factors in the development of gastric cancer with special reference to the early-onset subtype

Nowadays, gastric cancer is one of the most common neoplasms and the fourth cause of cancer-related death on the world. Regarding the age at the diagnosis it is divided into early-onset gastric carcinoma (45 years or younger) and conventional gastric cancer (older than 45). Gastric carcinomas are rarely observed in young population and rely mostly on genetic factors, therefore provide the unique model to study genetic and environmental alternations. The latest research on early-onset gastric cancer are trying to explain molecular and genetic basis, because young patients are less exposed to environmental factors predisposing to cancer. In the general population, Helicobacter pylori, has been particularly associated with intestinal subtype of gastric cancers. The significant association of Helicobacter pylori infection in young patients with gastric cancers suggests that the bacterium has an etiologic role in both diffuse and intestinal subtypes of early-onset gastric cancers. In this paper we would like to ascertain the possible role of Helicobacter pylori infection in the development of gastric carcinoma in young patients. The review summarizes recent literature on early-onset gastric cancers with special reference to Helicobacter pylori infection.

The epidemiology of Helicobacter pylori infection in Europe and the impact of lifestyle on its natural evolution toward stomach cancer after infection: A systematic review

BACKGROUND

Helicobacter pylori is a recognized cause of stomach cancer, but only a fraction of infected subjects develop cancer. This systematic review 1, summarizes the prevalence of infection with this bacterium in Europe; and 2, reviews the possible impact of particular lifestyles in progression from infection to stomach cancer.

MATERIALS AND METHODS

A systematic literature search was conducted in two databases by two independent investigators. Studies describing prevalence of infection among European healthy adult populations and worldwide studies analyzing the impact of lifestyle factors in association with H. pylori on stomach cancer risk were included.

RESULTS

Variable H. pylori infection prevalence was observed depending on region and study period. The lowest infection prevalences were found in Northern Europe, while the highest were in Eastern and Southern Europe, up to 84% in Portugal and Poland. Studies on smoking, salt, and meat consumption demonstrated increased risks of developing stomach cancer among H. pylori-infected individuals, while studies relating the intake of fruit, vegetables, and vitamins demonstrated decreased risks, but the levels of significance differed importantly between studies. No significant interaction could be found for alcohol consumption or physical activity.

CONCLUSIONS

Recent data showed remaining high H. pylori infection rates in several European regions. This systematic review suggests that a number of correctable lifestyle factors could impact the disease progression toward H. pylori-associated stomach cancer. However, additional research is required to determine the potential role of targeted interventions in reducing stomach cancer development after H. pylori infection.

Assessing safety and feasibility of 'pure' laparoscopic total gastrectomy for advanced gastric cancer in the West. Review article

BACKGROUND

Gastric cancer is reported to be the fourth most common cancer and the second leading cause of cancer-related death worldwide. Minimally invasive surgical treatment for gastric cancer is a very challenging approach which offers undoubtedly important advantages.

MATERIALS AND METHODS

There is intense debate concerning the minimally invasive surgical approach for advanced gastric cancer especially in the Western population. A careful literature search was conducted in order to clarify the feasibility and safety of pure laparoscopic total gastrectomy in the West.

RESULTS

Herewith we aim to summarize the current scientific evidence assessing the feasibility and short-term outcomes of laparoscopic gastrectomy for advanced gastric cancer in the West. A lack of data from Western institutions regarding minimally invasive surgical approach for gastric cancer is yet a reality. Nevertheless, the laparoscopic procedure appears to provide satisfactory short-term oncologic outcomes and improved postoperative outcomes.

CONCLUSION

It is obvious that future well-conducted trials on long-term results are necessary for Western patients in order safe conclusions to be reached regarding a potential definitive 'place' for laparoscopy in the curative gastric cancer treatment.

Systematic review with meta-analysis: the worldwide prevalence of Helicobacter pylori infection

BACKGROUND

The epidemiology of Helicobacter pylori infection is poorly understood.

AIM

To establish the reported regional and national prevalence of H. pylori infection, stratified by age and gender.

METHODS

All relevant English publications from 2000 to 2017 cited by PubMed and Scopus were retrieved using comprehensive combinations of keywords. The overall prevalence of H. pylori was estimated using both random effect and fixed effect meta-analyses, and presented as prevalence rate (% and 95% CI). The analyses were extended by separation into gender and age groups.

RESULTS

A total of 14 056 records were obtained initially. After applying exclusion criteria in several steps, 183 studies were selected. Analysis of 410 879 participants from 73 countries in six continents revealed an overall prevalence of 44.3% (95% CI: 40.9-47.7) worldwide. This rate ranged from 50.8% (95% CI: 46.8-54.7) in developing countries compared with 34.7% (95% CI: 30.2-39.3) in developed countries. The global H. pylori infection rate was 42.7% (95% CI: 39-46.5) in females compared to 46.3% (95% CI: 42.1-50.5) in males. The prevalence in adults (≥18 years) was significantly higher than in children (48.6% [95% CI: 43.8-53.5] vs 32.6% [95% CI: 28.4-36.8], respectively). There was a statistically nonsignificant decrease in the prevalence in 2009-2016 compared with the 2000-2009 period.

CONCLUSIONS

The observed differences between countries appear to be due to economic and social conditions. H. pylori infection can be a benchmark for the socioeconomic and health status of a country. Further studies are suggested to investigate the natural history of the acquisition of H. pylori infection from childhood into adult life.

Trends in gastric cancer mortality and in the prevalence of Helicobacter pylori infection in Portugal

Portugal has the highest gastric cancer mortality rates in Western Europe, along with high prevalences of Helicobacter pylori infection. Monitoring their trends is essential to predict the burden of this cancer. We aimed to quantify time trends in gastric cancer mortality in Portugal and in each administrative region, and to compute short-term predictions, as well as to describe the prevalence of H. pylori infection, through a systematic review. Joinpoint analyses were used to identify significant changes in sex-specific trends in gastric cancer age-standardized mortality rates (ASMR) and to estimate annual percent changes (APC). The most recent trends were considered to compute estimates up to 2020 by adjusting Poisson regression models. We searched PubMed and IndexRMP to identify studies carried out in Portugal reporting the prevalence of H. pylori. Gastric cancer mortality has been decreasing in Portugal since 1971 in men (from ASMR=55.3/100 000; APC=-2.4, 95% confidence interval: -2.5 to -2.3) and since 1970 in women (from ASMR=28.0/100 000; APC=-2.8, 95% confidence interval: -2.9 to -2.7), although large regional differences were observed. Predicted ASMR for 2015 and 2020 were 18.8/100 000 and 16.7/100 000 for men and 8.5/100 000 and 7.4/100 000 for women, respectively. The prevalence of H. pylori varied from almost 5% at 0.5-2 years to just over 90% at 70 years or more. No consistent variation was observed since the 1990s. The downward trends in mortality rates are expected to remain in the next decades. The high prevalence of H. pylori infection across age groups and studies from different periods shows a large potential for decrease in the burden of gastric cancer in Portugal.

Efficacy and tolerability of culture-guided treatment for Helicobacter pylori infection

OBJECTIVE

The aim of this study was to evaluate the efficacy/tolerability of a culture-guided approach in the eradication of Helicobacter pylori and identify factors associated with antibiotic resistance/treatment failure.

PATIENTS AND METHODS

This retrospective single-center study included patients who underwent culture-guided treatment for H. pylori infection, after two ineffective eradication attempts, between October 2012 and December 2016. We assessed the following demographic and clinical data of the patients: sex, age, BMI, alcohol and tobacco consumption, history of dyspepsia, peptic ulceration and first-degree relatives with gastric cancer, antibiotic susceptibility results, treatment composition, tolerability, and success. The treatment success was confirmed by a monoclonal stool antigen test.

RESULTS

Culture-guided treatment was performed in 42 patients (57% women, mean age±SD: 48.9±11.4 years). The rates of antibiotic resistance were as follows: clarithromycin 86%, metronidazole 67%; levofloxacin 52%, tetracycline 2%, and amoxicillin and rifampicin 0%. Double resistance to clarithromycin and metronidazole was found in 59.5% of the patients. Most patients showed resistance to less than three antibiotics, but 31% were resistant to three or more. Intention-to-treat and per-protocol eradication rates were 59.5 and 61.5%. Adverse events occurred in 15 (35.7%) patients, but only two (4.8%) patients did not complete treatment because of adverse events. Only age more than 50 years was associated with resistance to three or more antibiotics. Having a first-degree relative with gastric cancer was associated with treatment failure and having a BMI of at least 25 kg/m protected from failure.

CONCLUSION

Third-line culture-guided treatment often fails to eradicate H. pylori infection. We need to find factors other than in-vitro antibiotic resistance to explain these suboptimal results.

Helicobacter pylori serological biomarkers of gastric cancer risk in the MCC-Spain case-control Study

BACKGROUND

Helicobacter pylori infection is one of the main risk factors for non-cardia gastric cancer. However, only a minority of infected persons develop the disease. This study aims at identifying H. pylori related serological biomarkers of risk for gastric cancer.

METHODS

Incident gastric cancer cases and population controls (age, sex and region frequency-matched) from the MCC-Spain multicase-control Study were included. Seroreactivities against 16H. pylori proteins were determined using multiplex serology. Infection was defined as seropositivity against≥4 proteins. Relation of serological results to non-cardia and cardia gastric cancer was assessed using multivariable mixed logistic regression and principal components analysis.

RESULTS

Seroprevalence was 88% among 2071 controls, 95% among 202 non-cardia gastric cancer cases (OR=1.9 (95% CI: 1.0-3.6)) and 85% among 62 cardia cancer cases (OR=0.5 (95% CI: 0.3-1.1)). In infected subjects, seropositivity for UreA, HP231, NapA and Cagδ was associated with lower non-cardia gastric cancer risk, while seropositivity for CagA and VacA was associated with higher risk. Seropositivity for CagA and seronegativity for Cagδ maintained the association after additional adjustment by serostatus of significant proteins. We identified two antibody reactivity patterns: the "virulent-pattern", related to a threefold higher risk of non-cardia gastric cancer and the "non-virulent pattern", related to a 60% decreased risk (4th vs. first quartile).

CONCLUSIONS

In our population, people seropositive for H. pylori were characterized by two patterns of antibody reactivity against H. pylori proteins: 1) Combined high seroreactivity against several proteins, associated with a lower non-cardia gastric cancer risk, and 2) High seroreactivity against CagA and VacA, associated with an increased risk.

Sex-differences in the prevalence of Helicobacter pylori infection in pediatric and adult populations: Systematic review and meta-analysis of 244 studies

BACKGROUND

The main outcome of Helicobacter pylori infection, i.e. gastric cancer, is more frequent in men, but there is no comprehensive synthesis of the evidence on a potential role of sex in the acquisition and/or persistence of infection.

AIMS

To quantify the association between sex and H. pylori infection in pediatric and adult populations, through systematic review and meta-analysis.

METHODS

PubMed^® was searched, from inception to September 2015, to identify population-based studies reporting the prevalence and/or incidence of H. pylori infection in both sexes. Odds ratios (OR) or data to compute them were extracted; adjusted estimates were preferred, whenever available. The DerSimonian and Laird method was used to compute summary estimates and respective 95% confidence intervals (95%CI), separately for children and adults.

RESULTS

Among a total of 244 studies, mostly cross-sectional, male sex was associated with a greater prevalence of H. pylori infection, both in children (102 studies, OR=1.06, 95%CI: 1.01, 1.12, I²=43.7%) and adults (169 studies, OR=1.12, 95%CI: 1.09, 1.15, I²=68.5%). An underrepresentation of studies showing a negative association between male sex and infection was observed (Egger's test: p=0.006).

CONCLUSIONS

Although further research is needed to understand the mechanisms by which sex may influence the acquisition and/or persistence of infection, our results support a small contribution of sex differences in the prevalence of infection to the male predominance of H. pylori-related outcomes, including gastric cancer.

Gastric Cancer in Southern Europe: High-Risk Disease

Gastric cancer is an aggressive disease. Several risk factors are involved in gastric cancer pathogenesis, likely Helicobacter pylori (H. pylori) infection, genetic factors in hereditary syndromes, lifestyle, and diet. However, well-implemented screening strategies are lacking in most countries, including those in Southern Europe. Nevertheless, gastric cancer outcomes are better in some Southern European countries than in others, likely because of the incidence and distribution of different histologic types. Robotic surgery has been gaining favor as a treatment of early-stage disease, and the need for perioperative chemotherapy or adjuvant chemoradiotherapy (CRT) for locally advanced disease has been debated. In the metastatic setting, trastuzumab in combination with chemotherapy has helped to extend survival compared with chemotherapy alone for HER2-positive disease. This article will describe how gastric cancer is assessed and treated in Southern Europe in an attempt to correlate these approaches from a global perspective.

Gastric Cancer in Southern Europe: High-Risk Disease

Gastric cancer is an aggressive disease. Several risk factors are involved in gastric cancer pathogenesis, likely Helicobacter pylori (H. pylori) infection, genetic factors in hereditary syndromes, lifestyle, and diet. However, well-implemented screening strategies are lacking in most countries, including those in Southern Europe. Nevertheless, gastric cancer outcomes are better in some Southern European countries than in others, likely because of the incidence and distribution of different histologic types. Robotic surgery has been gaining favor as a treatment of early-stage disease, and the need for perioperative chemotherapy or adjuvant chemoradiotherapy (CRT) for locally advanced disease has been debated. In the metastatic setting, trastuzumab in combination with chemotherapy has helped to extend survival compared with chemotherapy alone for HER2-positive disease. This article will describe how gastric cancer is assessed and treated in Southern Europe in an attempt to correlate these approaches from a global perspective.

The All-Age Prevalence of Helicobacter pylori Infection and Potential Transmission Routes. A Population-Based Study

BACKGROUND AND AIMS

Previous research on H. pylori epidemiology has mostly focused on adult populations. We have aimed to study H. pylori prevalence in all age groups including children and adolescents and to identify potential routes of transmission.

METHODS

Subjects from all age groups (children 0-11 years, adolescents 12-17 years and adults ≥18 years of age), recruited from both an urban and a rural community in Northern Norway, were invited to provide stool samples for the diagnosis of H. pylori antigen and to fill in a questionnaire (adult and adolescents only) on gastrointestinal symptoms, lifestyle factors and biometric data.

RESULTS

A total of 1 624 (35.3%) of the invited subjects, including 173 (39.3%) of the children, 46 (19.2%) of the adolescents, and 1 416 (36.1%) of the adults, responded to the invitation. H. pylori infection was nearly undetectable (0.6%) among the children, whereas the prevalence increased from 20% in adolescents toward a peak of 45% in the highest age group. Univariate analyses of possible risk factors of H. pylori infection showed significant associations to private well water, the use of outhouse toilet, and having farm animals in childhood, but the associations waned in multivariate analyses.

CONCLUSIONS

In our populations, with apparent high hygienic standards, the transmission of H. pylori infection may start not only in childhood, but also in adolescence, where potential transmission routes may be outdoor toilet use, private well water, and farm animals.

Trends in Gastric and Esophageal Cancer Incidence in Northern Portugal (1994-2009) by Subsite and Histology, and Predictions for 2015

Introduction

Gastric cancer (GC) and esophageal cancer (EC) share risk factors, and the incidence trends reflect differences in etiology according to their subtypes. We aimed to describe the incidence trends of GC (by topography) and EC (by histological type) in northern Portugal for 1994-2009 and to estimate the incidence for 2015. We further analyzed exposure to the main risk factors for these cancers in the region over the last decades.

Methods

GC and EC data were obtained from the North Region Cancer Registry of Portugal (RORENO). Joinpoint regression was used to compute annual percent changes (APC) in incidence trends. Poisson regression yielded estimates for 2015. A literature review up to 2014 provided data on exposure to risk factors.

Results

GC rates decreased in 1994-2009 (men, APC = −1.3; women, APC = −1.6); GC, unspecified subtype, had the steepest decline since the early 2000s (men, APC = −4.9; women, APC = −6.3). The incidence for 2015 will increase for EC in men (up to ≈190 cases) and stabilize in women (≈30) and for GC (≈730 men, ≈500 women). Increasing prevalence of tobacco smoking among women and overweight/obesity, fairly stable prevalence of alcohol, fruit and vegetable consumption, and no trend for Helicobacter pylori infection were observed.

Conclusions

The declining incidence of GC unspecified subtype indicated an improvement in cancer registration accuracy, but precluded a sound assessment of trends by subtype. Variations in the prevalence of exposure to some risk factors were consistent with observed incidence trends, and future studies should aim to quantify their contribution to the GC and EC burden in the region.

Relevance of Helicobacter pylori vacA 3'-end Region Polymorphism to Gastric Cancer

BACKGROUND

Helicobacter pylori vacA genotypes play an important role in the pathogenesis of severe gastrointestinal disease.

MATERIALS AND METHODS

We identified a novel polymorphic site in the 3'-end region of H. pylori vacA gene, denoted by c1/-c2 (c1: with deletion of 15 bp), and examined associations of this and the previous four sites as well as cagA status with gastroduodenal diseases, in a total of 217 Iranian H. pylori isolates. Histopathologic evaluations were performed and patients with gastric cancer (GC) were further classified based on the anatomic site of tumor, including cardia and noncardia GC, and the histopathologic type of tumor, including intestinal- and diffuse-type GC.

RESULTS

The vacA m1, i1, d1, c1, and cagA genotypes were significantly associated with an increased risk of GC, the odds ratio (95% confidence interval) was 4.29 (2.03-9.08), 6.11 (2.63-14.19), 3.18 (1.49-6.76), 15.13 (5.86-39.01), and 2.59 (1.09-6.12), respectively. The vacA c1 genotype had an increased age- and sex-adjusted risk for GC by the multiple logistic regression analysis; the OR was 38.32 (95% CI, 6.60-222.29). This association was independent of and larger than the associations of the m-, i-, and d-type of vacA or cagA status with GC. No significant correlation was found between s1, whether independently or in combination, and the risk of GC or peptic ulcer disease (PUD). The vacA i1 and cagA genotypes were linked to an increased risk of PUD; the OR (95% CI) was 2.80 (1.45-5.40) and 2.62 (1.23-5.61), respectively. The presence of both the vacA i1 and cagA genotypes further increased the risk of PUD; the OR was 5.20 (95% CI, 1.92-14.03).

CONCLUSION

The H. pylori vacA c1 genotype might therefore be one of the strongest risk predictors of GC in male patients aged ≥55 in Iran.

Pathological and Clinical Correlation between Celiac Disease and Helicobacter Pylori Infection; a Review of Controversial Reports

There are overwhelming reports and descriptions about celiac associated disorders. Although there is a clear genetic association between celiac disease (CD) and some gastrointestinal disorders, there are controversial reports claiming an association between CD and Helicobacter pylori (H. pylori) infection. Different studies indicated the possible association between lymphocytic gastritis and both CD and H. pylori infection, although this evidence is not consistently accepted. Also it was shown that an increase in intraepithelial lymphocytes count is associated with both H. pylori infection and celiac disease. Therefore the following questions may raise: how far is this infection actually related to CD?, which are the underlying patho-mechanisms for these associations? what are the clinical implications? what is the management? and what would be the role of gluten free diet in treating these conditions? PubMed (PubMed Central), Ovid, ISI of web knowledge, and Google scholar were searched for full text articles published between 1985 and 2015. The associated keywords were used, and papers described particularly the impact of pathological and clinical correlation between CD and H. pylori infection were identified. In this review we tried to answer the above questions and discussed some of the recent developments in the pathological and clinical aspects of CD and H. pylori infection.

Connecting the dots on health inequalities--a systematic review on the social determinants of health in Portugal

INTRODUCTION

Health inequalities are recognised as a public health issue worldwide, but only a few countries have developed national strategies to monitor and reduce them. Despite its considerable health inequalities, Portugal seems to lack a systematic strategy to tackle them, possibly due to the absence of organised evidence on the issue. We performed a systematic review that aimed to describe the available evidence on social inequalities in health in Portugal, in order to contribute towards a comprehensive and focused strategy to tackle them.

METHODS

We followed the PRISMA guidelines and searched Scopus, Web of Science and PubMed for studies that looked at the association between a measure of socioeconomic status and a health outcome in the Portuguese resident population since the year 2000. We excluded health behaviours and healthcare use from our search. We performed a qualitative description of the results.

RESULTS

Seventy-one publications were selected, all reporting observational analyses, most of them using cross-sectional data. These publications showed strong evidence for health inequalities related to education and gender, chiefly for obesity, self-rated health and mental health.

CONCLUSIONS

Analysis of the eligible publications showed that current research does not seem to have consistently covered the link between health and key Portuguese social problems. A strategy focusing on the monitoring of most prevalent diseases, most determining socioeconomic factors and vulnerable populations would be crucial to guide academic research in a country in which health inequalities are so ubiquitous and deeply rooted.

REGISTRATION

This systematic review is not registered.

Review article: the prevalence of Helicobacter pylori and the incidence of gastric cancer across Europe

BACKGROUND

There is little up-to-date review evidence on the prevalence of Helicobacter pylori across Europe.

AIM

To establish regional and national patterns in H. pylori prevalence across Europe. Secondly, to establish trends over time in H. pylori prevalence and gastric cancer incidence and, thirdly, to report on the relationship between H. pylori prevalence and age group across Europe.

METHODS

A review of H. pylori prevalence from unselected surveys of adult or general populations across 35 European countries and four European regions since 1990. Secondly, an analysis of trends over time in H. pylori prevalence and in gastric cancer incidence from cancer registry data.

RESULTS

Helicobacter pylori prevalence was lower in northern and western Europe than in eastern and southern Europe (P < 0.001). In 11 of 12 European studies that reported on trends, there were sharp reductions in H. pylori prevalence (mean annual reduction = 3.1%). The mean annual reduction in the incidence of gastric cancer across Europe from 1993 to 2007 was 2.1% with little variation regionally across Europe (north 2.2%, west 2.3%, east 1.9% and south 2.0%). Sharp increases in age-related prevalence of H. pylori often levelled off for middle age groups of about 50 years onwards, especially in areas with high prevalence.

CONCLUSIONS

This review shows that H. pylori prevalence is much higher in less affluent regions of Europe and that age-related increases in prevalence are confined to younger age groups in some areas. There were sharp reductions in both H. pylori prevalence and gastric cancer incidence throughout Europe.

Review article: the global emergence of Helicobacter pylori antibiotic resistance

BACKGROUND

Helicobacter pylori is one of the most prevalent global pathogens and can lead to gastrointestinal disease including peptic ulcers, gastric marginal zone lymphoma and gastric carcinoma.

AIM

To review recent trends in H. pylori antibiotic resistance rates, and to discuss diagnostics and treatment paradigms.

METHODS

A PubMed literature search using the following keywords: Helicobacter pylori, antibiotic resistance, clarithromycin, levofloxacin, metronidazole, prevalence, susceptibility testing.

RESULTS

The prevalence of bacterial antibiotic resistance is regionally variable and appears to be markedly increasing with time in many countries. Concordantly, the antimicrobial eradication rate of H. pylori has been declining globally. In particular, clarithromycin resistance has been rapidly increasing in many countries over the past decade, with rates as high as approximately 30% in Japan and Italy, 50% in China and 40% in Turkey; whereas resistance rates are much lower in Sweden and Taiwan, at approximately 15%; there are limited data in the USA. Other antibiotics show similar trends, although less pronounced.

CONCLUSIONS

Since the choice of empiric therapies should be predicated on accurate information regarding antibiotic resistance rates, there is a critical need for determination of current rates at a local scale, and perhaps in individual patients. Such information would not only guide selection of appropriate empiric antibiotic therapy but also inform the development of better methods to identify H. pylori antibiotic resistance at diagnosis. Patient-specific tailoring of effective antibiotic treatment strategies may lead to reduced treatment failures and less antibiotic resistance.

European Code against Cancer 4th Edition: Infections and Cancer

Of the 2,635,000 new cancer cases (excluding non-melanoma skin cancers) occurring in the European Union (EU) in 2012, it is estimated that approximately 185,000 are related to infection with human papillomaviruses (HPVs), hepatitis B and C viruses (HBV and HCV), and Helicobacter pylori (H. pylori). Chronic infection with these agents can lead to cancers of the cervix uteri, liver, and stomach, respectively. Chronic infection with HCV can also lead to B-cell non-Hodgkin lymphoma. Human immunodeficiency virus (HIV) infection continues to be of major public health importance in several EU countries and increases cancer risk via HIV-induced immunosuppression. The fourth edition of the European Code Against Cancer presents recommendations on effective and safe preventive interventions in order to reduce the risk of infection-related cancers in EU citizens. Based on current available evidence, the fourth edition recommends that parents ensure the participation of their children in vaccination programs against HBV (for newborns) and HPV (for girls). In the 'Questions and Answers' (Q&As) section about vaccination and infections in the website for the European Code Against Cancer, individuals who are at risk of chronic HBV or HCV are advised to seek medical advice about testing and obtaining treatment when appropriate. Individuals most at risk of HIV are advised to consult their doctor or healthcare provider to access counselling and, if needed, testing and treatment without delay. Information about H. pylori testing and treatment is also provided as testing might currently be offered in some high-risk areas in Europe. The rationale and supporting evidence for the recommendations on vaccination in the European Code Against Cancer, and for the main recommendations on vaccination and infection in the Q&As, are explained in the present review.