Helicobacter pylori: a poor man's gut pathogen?

Exploring the Molecular Mechanisms of Macrolide Resistance in Laboratory Mutant Helicobacter pylori

Resistance to clarithromycin, a macrolide antibiotic used in the first-line treatment of Helicobacter pylori infection, is the most important cause of treatment failure. Although most cases of clarithromycin resistance in H. pylori are associated with point mutations in 23S ribosomal RNA (rRNA), the relationships of other mutations with resistance remain unclear. We examined possible new macrolide resistance mechanisms in resistant strains using next-generation sequencing. Two resistant strains were obtained from clarithromycin-susceptible H. pylori following exposure to low clarithromycin concentrations using the agar dilution method. Sanger sequencing and whole-genome sequencing were performed to detect resistance-related mutations. Both strains carried the A2142G mutation in 23S rRNA. Candidate mutations (T1495A, T1494A, T1490A, T1476A, and G1472T) for clarithromycin resistance were detected in the Mutant-1 strain. Furthermore, a novel mutation in the gene encoding for the sulfite exporter TauE/SafE family protein was considered to be linked to clarithromycin resistance or cross-resistance, being identified as a target for further investigations. In the Mutant-2 strain, a novel mutation in the gene that encodes DUF874 family protein that can be considered as relevant with antibiotic resistance was detected. These mutations were revealed in the H. pylori genome for the first time, emphasizing their potential as targets for advanced studies.

Helicobacter pylori Diagnosis and Treatment in Africa: The First Lagos Consensus Statement of the African Helicobacter and Microbiota Study Group

BACKGROUND

Helicobacter pylori (H. pylori) infection is the most prevalent type of bacterial infection. Current guidelines from different regions of the world neglect specific African conditions and requirements. The African Helicobacter and Microbiota Study Group (AHMSG), founded in 2022, aimed to create an Africa-specific consensus report reflecting Africa-specific issues.

SUMMARY

Eighteen experts from nine African countries and two European delegates supported by nine African collaborators from eight other countries prepared statements on the most important African issues in four working groups: (1) epidemiology, (2) diagnosis, (3) indications and prevention, and (4) treatment. Limited resources, restricted access to medical systems, and underdeveloped diagnostic facilities differ from those of other regions. The results of the individual working groups were presented for the final consensus voting, which included all board members.

KEY MESSAGES

There is a need for further studies on H. pylori prevalence in Africa, with diagnosis hinged on specific African situation. Treatment of H. pylori in the African setting should be based on accessibility and reimbursement, while indication and prevention should be defined in specific African countries.

Frequency and seasonality of viable Helicobacter pylori in drinking water in Dhamar Governorate, Yemen

Helicobacter pylori is an important and common bacterial pathogen in humans. The accumulated evidence of the existence of H. pylori in water from different environmental sources suggests a water-borne transmission route. This study aimed to investigate the occurrence of H. pylori in different water sources used by human populations in Dhamar Governorate, Yemen. 250 samples were randomly collected from the municipal water supply network, wells, and springs. The samples were processed, plated onto modified campy-blood agar, and incubated under microaerobic conditions for 4-10 days. Bacterial identification was based on morphological properties and biochemical tests. Bacteriological analysis showed that 9.6% and 13.2% of tap and surface water samples were contaminated with H. pylori, respectively. Despite a higher frequency in samples from rural areas, these were not significantly (p=0.068) more contaminated than the samples from urban areas. Regarding the seasonal variations of H. pylori detection, 85.71% of positive samples were detected in the late winter and spring seasons (February to May). To conclude, H. pylori transmission through water is likely to occur in Dhamar Governorate. Further prospective studies are highly recommended to provide further evidence and a clearer picture of H. pylori transmission.

Sero- and Feco-Prevalence of Helicobacter pylori Infection and Its Associated Risk Factors among Adult Dyspeptic Patients Visiting the Outpatient Department of Adet Primary Hospital, Yilmana Densa District, Northwest Ethiopia

Background

Most gastric cancers in the world are attributed to Helicobacter pylori (H. pylori) infections. The prevalence of H. pylori infection is influenced by socioeconomic status, hygiene, and lifestyle of the population. This study aimed to assess sero- and feco-prevalence of H. pylori infections and its associated risk factors among adult dyspeptic patients visiting the outpatient department of Adet Primary Hospital, Yilmana Densa District, northwest Ethiopia.

Methods

A hospital-based cross-sectional study was conducted from February 10, 2022 to April 10, 2022. The study participants were selected using a systematic random sampling technique. The data were collected by pretested questionnaires. Blood and stool specimens were collected from each patient for antibody and H. pylori antigen tests, respectively. The data were analyzed using Statistical Package for Social Science (SPSS) version 26.0. A logistic regression model was used to assess the strength of association between H. pylori positivity and risk factors.

Results

The sero- and feco-prevalence of H. pylori infection was 62% and 51.1%, respectively. In those patients who had a positive result with either the antibody (Ab) or antigen (Ag) test, rural residence (AOR = 5.55; 95% CI: 2.34-13.14; p < 0.001), alcohol consumption (AOR = 12.34; 95% CI: 2.29-66.51; p=0.003), having no awareness about H. pylori transmission (AOR = 4.76; 95% CI: 1.86-12.15; p=0.001), using pond/river as a source of drinking water (AOR = 5.22; 95% CI: 1.91-14.27; p=0.001), and open field defecation (AOR = 4.19; 95% CI: 1.67-10.52; p=0.002) were the explanatory risk factors significantly associated with H. pylori infection.

Conclusion

This study showed that the prevalence of H. pylori infection was very high. Most cases of gastric cancers are ascribed to H. pylori infection. Therefore, education should be given to communities so as to increase their awareness of the infection and the associated major explanatory risk factors identified in the present study.

Gastric troubles in Iran: The role of social and economic factors in Helicobacter pylori infection

Background

Helicobacter pylori infection is a major risk factor for gastric cancer in Iran, but the impact of socioeconomic factors on its prevalence is poorly understood. This study aimed to assess the socioeconomic inequalities and risk factors associated with H. pylori infection in Iran.

Methods

This cross-sectional study was conducted based on the PERSIAN cohort study. A total of 20460 individuals aged 35 to 70 years in Ardabil, Iran were included in the study. H. pylori infection was determined based on stool tests and clinical records. Multilevel logistic regression models with random intercepts at household and community levels were used to identify risk factors associated with H. pylori prevalence. The concentration index (CIn) and concentration curve (CC) were employed to assess socioeconomic-related inequality.

Results

In this study, 70.4% (CI 69.6-71.0) of the participants were infected with H. pylori, with a higher prevalence in women (71.2%) than men (69.6%). Age (OR: 1.37, CI: 1.17-1.61), sex (OR: 1.20, CI: 1.12-1.28), level of education (OR: 1.33, CI: 1.17-1.49), cardiac disease (OR: 1.32, CI:1.18-1.46), and BMI groups (OR: 2.49, CI: 1.11-5.58) were significantly associated with H. pylori infection based on the multivariable logistic regression. The results of the CIn and CC indicated that H. pylori were more prevalent among economically disadvantaged groups (CIn: -0.1065; [-0.1374 to -0.0755]).

Conclusion

The prevalence of H. pylori in Iran is higher than in other developing countries, and significant socioeconomic inequality exists between the poor and the rich. To reduce the rate of gastric cancer, socio-economic and demographic factors, especially the poor and people with low levels of education, should be considered.

The Role of Adhesion in Helicobacter pylori Persistent Colonization

Helicobacter pylori (H. pylori) has coevolved with its human host for more than 100 000 years. It can safely colonize around the epithelium of gastric glands via their specific microstructures and proteins. Unless patients receive eradication treatment, H. pylori infection is always lifelong. However, few studies have discussed the reasons. This review will focus on the adhesion of H. pylori from the oral cavity to gastric mucosa and summarize the possible binding and translocation characteristics. Adhesion is the first step for persistent colonization after the directional motility, and factors related to adhesion are necessary. Outer membrane proteins, such as the blood group antigen binding adhesin (BabA) and the sialic acid binding adhesin (SabA), play pivotal roles in binding to human mucins and cellular surfaces. And this may offer different perspectives on eradication.

School-based Hygiene Intervention to Prevent HelicObacter Pylori infection among childrEn (SHIP HOPE): protocol for a cluster-randomised controlled trial

INTRODUCTION

Helicobacter pylori infection rates are high in China and worldwide, and maintaining good hygiene is effective in preventing H. pylori infection. Childhood is a critical stage for developing good hygiene practices. Therefore, in this study, we aimed to explore whether a comprehensive hygiene intervention can prevent H. pylori infection in primary schools in China.

METHODS AND ANALYSIS

The School-based Hygiene Intervention to Prevent HelicObacter Pylori infection among childrEn study is a cluster-randomised controlled trial, which will include approximately 2400 children in grades 2-4 from 60 classes in 10 primary schools of Linqu County, Shandong Province. Schools will be randomly assigned (1:1) via a computer-generated list, to receive either comprehensive hygiene intervention (intervention) or the usual health education lessons (control), with stratification by area (urban or rural). The interventions will include the following: (1) Children's education: lessons and cartoon books designed to provide basic knowledge about hygiene, H. pylori, hand hygiene, diet and oral hygiene will be provided to children; (2) Caregiver's education: children will be empowered to share hygiene-related knowledge with their caregivers as homework; caregivers will be also invited to the school for hygiene lessons; (3) School hygiene promotion: suggestions will be provided for improving the hygienic environment. Children in control schools will receive usual health education lessons according to the arrangements of each school. The primary outcome is the prevalence and incidence of H. pylori infection among children at 1-year follow-up. The secondary outcomes are H. pylori and hygiene knowledge, family eating customs and hygiene practices among children and their caregivers, as well as school absences owing to diarrhoea. Additionally, growth in children is set as an exploratory outcome. General linear mixed models will be used to analyse differences between the intervention and control schools.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the Institution Review Board of Tsinghua University (No: 20220020). Written informed consent will be obtained from each child and one of their caregivers. The findings of this study will be actively disseminated through scientific publications and conference presentations.

TRIAL REGISTRATION NUMBER

ChiCTR2200056191.

Recombinant Helicobacter pylori Vaccine Delivery Vehicle: A Promising Tool to Treat Infections and Combat Antimicrobial Resistance

Antimicrobial resistance (AMR) has become a global public health threat. Experts agree that unless proper actions are taken, the number of deaths due to AMR will increase. Many strategies are being pursued to tackle AMR, one of the most important being the development of efficient vaccines. Similar to other bacterial pathogens, AMR in Helicobacter pylori (Hp) is rising worldwide. Hp infects half of the human population and its prevalence ranges from <10% in developed countries to up to 90% in low-income countries. Currently, there is no vaccine available for Hp. This review provides a brief summary of the use of antibiotic-based treatment for Hp infection and its related AMR problems together with a brief description of the status of vaccine development for Hp. It is mainly dedicated to genetic tools and strategies that can be used to develop an oral recombinant Hp vaccine delivery platform that is (i) completely attenuated, (ii) can survive, synthesize in situ and deliver antigens, DNA vaccines, and adjuvants to antigen-presenting cells at the gastric mucosa, and (iii) possibly activate desired compartments of the gut-associated mucosal immune system. Recombinant Hp vaccine delivery vehicles can be used for therapeutic or prophylactic vaccination for Hp and other microbial pathogens.

International trends in esophageal cancer incidence rates by histological subtype (1990-2012) and prediction of the rates to 2030

BACKGROUND

We provide an up-to-date overview of recent international trends (1990-2012) and predicted trends (2013-2030) in the incidence rates of esophageal cancer.

METHODS

We used data from the Cancer Incidence in Five Continents (CI5plus) database that contains annual incidence data by cancer site, age, and sex as well as corresponding populations. The age-standardized esophageal cancer incidence rates of each country were calculated and plotted from 1990 through 2012 and were predicted to 2030 using a Bayesian age-period-cohort model.

RESULTS

Globally, esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) showed opposing trends between 1990 and 2012; ESCC showed a decreasing trend, with an AAPC of - 1.5 (95% CI - 2.4, - 0.7), yet EAC showed an increasing trend, with an AAPC of 5.2 (95% CI 4.2, 6.2). The increasing trend in EAC was commonly observed in high-income countries. The predicted trend to 2030 indicated that most countries will continue to experience a decreasing trend or a stable trend in esophageal cancer incidence, except Denmark, the Netherlands, and the UK, where the overall esophageal cancer incidence rates, mainly driven by EAC, are predicted to increase.

CONCLUSIONS

Decreasing trends in ESCC have been observed worldwide in both low- and middle-income countries and high-income countries, which may have been offset by increasing trends in EAC in high-income countries. The changing patterns of these two main subtypes of esophageal cancer may call for interventions, especially innovative interventions, to address obesity, GERD, and Barrett's esophagus.

miR-30c Increases the Intracellular Survival of Helicobacter pylori by Inhibiting Autophagy

Persistent Helicobacter pylori infection causes a variety of gastrointestinal diseases and even gastric cancer. H. pylori invades gastric epithelial cells to survive and proliferate, which is one of the key factors in persistent colonization. A Published study has confirmed that cells can eliminate intracellular H. pylori through xenophagy to maintain intracellular balance. However, a growing body of evidences indicate that H. pylori can inhibit xenophagy by miRNA through regulating the expression of key autophagy-related genes. Through western blot analysis, mRFP-GFP-LC3 transfection assay, and transmission electron microscopy, we found that H. pylori infection obstructed autophagy flux degradation stage in GES-1 cell lines. Gentamicin protection assay confirmed that inhibit xenophagy is benefit for intracellular H. pylori survive. miR-30c-1-3p and miR-30c-5p were upregulated in GES-1 cell lines after infecting with H. pylori, resulting in the negative regulation on xenophagy. Further studies through bioinformatics analysis and dual-luciferase reporter assays confirmed that ATG14 and ULK1 were the target genes of miR-30c-1-3p and that ATG12 was the target gene of miR-30c-5p. The overexpression of miR-30c-1-3p and miR-30c-5p reduces the expression of ATG14, ULK1, and ATG12 at mRNA level and also decreased intracellular H. pylori elimination in GES-1 cells. The above results suggested that the inhibition on xenophagy by miR-30c-1-3p and miR-30c-5p through ATG14, ULK1, and ATG12 targeting benefitted intracellular H. pylori in the evasion of xenophagy clearance.

Helicobacter pylori Pathogenicity Islands and Giardia lamblia Cysteine Proteases in Role of Coinfection and Pathogenesis

Helicobacter pylori is a well-known human-specific stomach pathogen that infects more than half of the world’s population. The infection with this bacterium can cause a variety of gastrointestinal problems, including chronic gastritis, peptic ulcers, and even cancer. H. pylori is a highly infectious bacterium. H. pylori causes an increase in gastric mucosa pH or gastric mucosa intestinal metaplasia. These modifications in the stomach environment are necessary for G. lamblia colonization to occur. Giardia lamblia is a flagellate protozoan parasite that can cause giardiasis in humans and other mammals. It dwells in the duodenum and upper jejunum. Globally, over 280 million cases of human giardiasis are predicted to occur each year. Simultaneous human colonization by G. lamblia and H. pylori is a typical occurrence since the viruses’ predisposing factors are similar in both groups. Giardiasis is a parasitic infection that affects both children and adults worldwide. Infection with Giardia is more common in underdeveloped countries. Globally, more than 200 million cases of giardiasis are detected each year. In contrast, the presence of G. lamblia in the host body triggers an immunological response comparable to that of H. pylori, with lymphocytes strongly polarized towards Th1. As a result, their combined presence exacerbates host tissue damage. The major goal of this seminar is to describe the pathophysiology, immunology, and clinical aspects of G. lamblia and H. pylori coinfection using a comprehensive search of PubMed, Lancet, and Google Scholar sources. Upper gastrointestinal problems such as upper abdominal pain, abdominal bloating, nausea, vomiting, epigastric pain/burning, and belching are all caused by both organisms. Differentiation by physical examination is impossible in people infected with both bacteria. For this coinfection distinction, a laboratory diagnosis is required. G. lamblia and H. pylori, when present together, have a synergistic effect on the host and can cause serious damage. As a result, researchers should delve deeper into the mechanics underlying this potential microbial interaction.

Helicobacter pylori Prevalence and Risk Factors in Three Rural Indigenous Communities of Northern Arizona

Helicobacter pylori (H. pylori) is one of the most common bacterial stomach infections and is implicated in a majority of non-cardia gastric cancer. While gastric cancer has decreased in the United States (US), the incidence in the Navajo Nation is nearly four times higher than surrounding Non-Hispanic White populations. Little is known about H. pylori prevalence in this population or other Indigenous communities in the lower 48 states. In this cross-sectional study, 101 adults representing 73 households from three Navajo Nation chapter communities completed surveys and a urea breath test for active H. pylori. Accounting for intrahousehold correlation, H. pylori prevalence was 56.4% (95% CI, 45.4–66.8) and 72% of households had at least one infected person. The odds of having an active infection in households using unregulated water were 8.85 (95% CI, 1.50–53.38) that of the use of regulated water, and males had 3.26 (95% CI, 1.05–10.07) higher odds than female. The prevalence of H. pylori in Navajo is similar to that seen in Alaska Natives. Further investigation into factors associated with prevention of infection is needed as well as understanding barriers to screening and treatment.

Helicobacter pylori virulence factors: relationship between genetic variability and phylogeographic origin

Background

Helicobacter pylori is a pathogenic bacteria that colonize the gastrointestinal tract from human stomachs and causes diseases including gastritis, peptic ulcers, gastric lymphoma (MALT), and gastric cancer, with a higher prevalence in developing countries. Its high genetic diversity among strains is caused by a high mutation rate, observing virulence factors (VFs) variations in different geographic lineages. This study aimed to postulate the genetic variability associated with virulence factors present in the Helicobacter pylori strains, to identify the relationship of these genes with their phylogeographic origin.

Methods

The complete genomes of 135 strains available in NCBI, from different population origins, were analyzed using bioinformatics tools, identifying a high rate; as well as reorganization events in 87 virulence factor genes, divided into seven functional groups, to determine changes in position, number of copies, nucleotide identity and size, contrasting them with their geographical lineage and pathogenic phenotype.

Results

Bioinformatics analyses show a high rate of gene annotation errors in VF. Analysis of genetic variability of VFs shown that there is not a direct relationship between the reorganization and geographic lineage. However, regarding the pathogenic phenotype demonstrated in the analysis of many copies, size, and similarity when dividing the strains that possess and not the cag pathogenicity island (cagPAI), having a higher risk of developing gastritis and peptic ulcer was evidenced. Our data has shown that the analysis of the overall genetic variability of all VFs present in each strain of H. pylori is key information in understanding its pathogenic behavior.

Effect of gastric microbiota on quadruple Helicobacter pylori eradication therapy containing bismuth

BACKGROUND

Helicobacter pylori (H. pylori) is an important pathogen that can cause a variety of diseases. Yet, full eradication of H. pylori remains a significant challenge in clinical practice. H. pylori and other microbial communities have complex interactions in the unique gastric microecological environment. However, it is not clear whether the interactions have any effect on the therapeutic effect of H. pylori.

AIM

The aim was to investigate the characteristics of the gastric microbiota with H. pylori infection and the influence on the H. pylori eradication treatment.

METHODS

Patients with H. pylori infection underwent gastroscopy and received treatment for eradication. The prescription included esomeprazole 20 mg bid, Livzon Dele 220 mg bid, amoxicillin 1000 mg bid, and clarithromycin 500 mg bid for 14 d. Patients who did not respond to treatment and failed eradication were compared with those who achieved eradication by 1:2 propensity matching. High-throughput sequencing of the gastric mucosal microbiota was performed, and the results were evaluated by alpha diversity analysis, beta diversity analysis, species correlation analysis, and metabolic pathway correlation analysis.

RESULTS

The eradication rate of all the patients was 95.5% (171/179). Twenty-four patients were enrolled in the study after propensity-matched scoring. There were eight cases in the failure group (patients who did not respond well to therapy) and 16 cases in the success group. The majority phyla in the two groups were the same, and included Proteobacteria, Bacteroides, Firmicutes, Actinomycetes, and Fusobacteria. The microbial diversity in the failure group had a decreasing trend (P = 0.092) and the species abundance was significantly lower (P = 0.031) compared with the success group. The high rate of H. pylori eradication was associated with Rhodococcus, Lactobacillus, and Sphingomonas, as they were significantly enriched in the successful group (P < 0.05). Veronococcus and Cilium were enriched in the mucosa of chronic atrophic gastritis patients compared with chronic superficial gastritis patients (P = 0.0466 and 0.0122, respectively). In both study groups, H. pylori was negatively correlated with other bacterial genera. More bacterial genera were directly related to H. pylori in the successful group compared with the failure group.

CONCLUSION

The effectiveness of quadruple H. pylori eradication therapy containing bismuth depended on gastric microbiota, and the high rate of H. pylori eradication was associated with the presence of Rhodococcus, Lactobacillus, and Sphingomonas.

Helicobacter pylori prevalence in healthy Mexican children: comparison between two non-invasive methods

Background

Helicobacter pylori detection in asymptomatic children with suspected infection or with symptoms that suggest gastric pathology is problematic, since most of the methods depend on the endoscopic study, an invasive and expensive method. Non-invasive methods can be a feasible alternative but must be validated. The purpose of this study was to evaluate the concordance between H. pylori DNA detection in saliva and dental plaque by PCR, with antigen detection in stool by immunochromatography, among asymptomatic children in the state of Guerrero, Mexico.

Methods

Dental plaque, saliva, and stool samples were obtained from 171 children between 6 and 12 years old. H. pylori detection in saliva and dental plaque was performed by PCR using specific primers for the 16S rRNA gene, while the detection in stool samples was performed by immunochromatography using the CerTest kit.

Results

We found an overall H. pylori prevalence of 59.6% (102/171). Of the H. pylori positive children 18% (20/111) were positive in saliva samples, 28.1% (34/121) in dental plaque samples, and 50.4% (71/141) in stool samples. A higher prevalence was found in girls (64.7%, p = 0.002). Although some of the children declared some dyspeptic symptoms, these were no related to H. pylori. In conclusion, we found a high prevalence of H. pylori in asymptomatic children and the highest proportion was detected by stool antigen test, which was the most feasible method to detect H. pylori infection.

Heterogeneity of Helicobacter pylori Strains Isolated from Patients with Gastric Disorders in Guiyang, China

Purpose

Chronic Helicobacter pylori infection causes peptic ulcers in a subpopulation of individuals and is a risk factor for the development of gastric cancer. Multiple infections and heteroresistant H. pylori contribute to poor treatment efficacy. Here, we investigated the extent of genetic diversity among H. pylori strains within a given host and its influence on the results of antibiotic (metronidazole, levofloxacin, clarithromycin, amoxicillin, and tetracycline) susceptibility testing.

Materials and Methods

Gastric mucosa biopsy samples were obtained from patients with gastric disorders, including 48 H. pylori positive patients, who were never previously treated for H. pylori infection. Five potential H. pylori colonies isolated from each sample were subcultured for enrichment. Enriched H. pylori colonies were identified through Gram staining and assays for urease, oxidase, and catalase. For each H. pylori monoclonal colony, the antibiotic susceptibility was assessed, genomic DNA was sequenced, and the cytotoxin-associated gene A (cagA) genotype was verified. Co-infection with multiple H. pylori strains was determined using random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR).

Results

Thirteen gastric mucosa biopsy samples were positive for H. pylori. Five monoclonal strains isolated from each of these 13 patients were identified as H. pylori. RAPD-PCR indicated that intra-patient monoclonal strains of H. pylori in 10 of the 13 samples exhibited heterogeneity. Among the 13 patients, intra-patient monoclonal strains isolated from 4 patients had identical cagA genotype, whereas intra-patient monoclonal strains isolated from the other 9 patients harbored more than one cagA genotype. The antibiotic susceptibility of five intra-patient monoclonal strains from seven patients was inconsistent.

Conclusion

The existence of heterogeneous H. pylori strains with resistance to different drugs and virulence were common within the gastric mucosa of an individual patient.

Prevalence of Helicobacter pylori infection and the incidence of the associated malignant and peptic ulcer disease (PUD) at Nelson Mandela Academic Hospital: a retrospective analysis

BACKGROUND

H. pylori infection is associated with both benign and malignant gastrointestinal diseases. However, no studies have been conducted locally describing the prevalence of H. pylori and its associated GIT diseases. The objectives of this study are to determine the prevalence of H. pylori, and the incidence of PUD and gastric malignancies among patients who are infected with H. pylori or who have the stigmata of previous exposure to H. pylori.

MATERIAL AND METHODS

Data was collected retrospectively from files of adult patients with upper gastro-intestinal symptoms from January to December, 2012. The gastric mucosal biopsy specimens were analyzed for the presence of H. pylori, chronic gastritis, PUD, and gastric malignancies.

RESULTS

Of 156 records there were 70 (45%) males and 86 (55%) females, with a median age of 56.5. The prevalence of H. pylori was 54.5%; 95% of 156 had chronic gastritis (CG). Ninety-sever percent of the 85 H. pylori positive and 93% of the 71 H. pylori negative patients had CG. However, the difference was not statistically significant (97% vs 93%, p = 0.322). The incidence of PUD was 16% and 10 (6.4%) had gastric malignancies, of which four (2.7%) and three (2%) were antral intestinal-type and proximal diffuse types, respectively. Three (2%) had gastric MALT lymphoma. The risk of both gastric malignancies and PUD was demonstrated to increase with advancing age.

DISCUSSION AND CONCLUSION

The prevalence of H. pylori was equivalent to the global prevalence; however, high prevalence of CG may be indicative of high local infection rate. The incidence of H. pylori and/or chronic gastritis-associated intestinal-type gastric adenocarcinoma, MALT lymphoma, and PUD is equivalent to that reported globally. Advancing age and active H. pylori infection or stigmata of past exposure thereto are associated with increased risk of peptic ulcers and malignant gastric diseases.

Global Burden, Risk Factors, and Trends of Esophageal Cancer: An Analysis of Cancer Registries from 48 Countries

Simple Summary

Esophageal cancer is the seventh most common cancer globally. Preventive measures and clinical management differ based on histologic subtype. However, information has been lacking on its most recent patterns according to histological subtype, associated risk factors, and epidemiological trends on a global scale. This study is a global analysis of the incidence/mortality trends of esophageal cancer in more than 48 countries/regions based on high quality population-based registries. We conclude that adenocarcinoma has already surpassed squamous cell carcinoma as the most frequent type of esophageal cancer in some western countries and is expected to increase in other countries. It is important to closely monitor and slow down the growing rates of obesity and metabolic syndrome, which are the important risk factors for adenocarcinoma. With the development of more advanced and less invasive technology, population-based targeted screening endoscopy would be recommended for high-risk individuals.

Abstract

This study aimed to examine the global burden, risk factors, and trends of esophageal cancer based on age, sex, and histological subtype. The data were retrieved from cancer registries database from 48 countries in the period 1980–2017. Temporal patterns of incidence and mortality were evaluated by average annual percent change (AAPC) using joinpoint regression. Associations with risk factors were examined by linear regression. The highest incidence of esophageal cancer was observed in Eastern Asia. The highest incidence of adenocarcinoma (AC) was found in the Netherlands, the United Kingdom, and Ireland. A higher AC/squamous cell carcinoma (SCC) incidence ratio was associated with a higher prevalence of obesity and elevated cholesterol. We observed an incidence increase (including AC and SCC) in some countries, with the Czech Republic (female: AAPC 4.66), Spain (female: 3.41), Norway (male: 3.10), Japan (female: 2.18), Thailand (male: 2.17), the Netherlands (male: 2.11; female: 1.88), and Canada (male: 1.51) showing the most significant increase. Countries with increasing mortality included Thailand (male: 5.24), Austria (female: 3.67), Latvia (male: 2.33), and Portugal (male: 1.12). Although the incidence of esophageal cancer showed an overall decreasing trend, an increasing trend was observed in some countries with high AC/SCC incidence ratios. More preventive measures are needed for these countries.

Predictive Effect of Helicobacter pylori in Gastric Carcinoma Development: Systematic Review and Quantitative Evidence Synthesis

Helicobacter pylori (H. pylori) is a bacterial pathogen implicated in gastritis, gastric ulceration, and gastric carcinoma. This study aimed to synthesize literature in providing evidence on the causative role of H. pylori in gastric carcinoma development. This study is based on assessing public literature using an applied meta-analysis, namely, quantitative evidence synthesis (QES). The analytic procedure uses DerSimonian-Laird, including assessing heterogeneity. The QES also utilizes meta-regression and the environmental effect associated with H. pylori in gastric cancer development. Eighteen studies are included in the QES. There is increased prevalence of H. pylori exposure among the cases. The heterogeneity between the CES and individual effect sizes is also significant. Despite controlling for the confoundings, there is increased exposure to H. pylori among the gastric cancer cases, regardless of the differences in the geographic location. H. pylori in this synthesized literature illustrates the contributory role of this microbe in gastric carcinoma. Additionally, regardless of geographic locale, namely, South Korea or Spain, H. pylori is implicated in gastric cancer development.

Identification of New Helicobacter pylori Subpopulations in Native Americans and Mestizos From Peru

Region-specific Helicobacter pylori subpopulations have been identified. It is proposed that the hspAmerind subpopulation is being displaced from the Americans by an hpEurope population following the conquest. Our study aimed to describe the genomes and methylomes of H. pylori isolates from distinct Peruvian communities: 23 strains collected from three groups of Native Americans (Asháninkas [ASHA, n = 9], Shimaas [SHIM, n = 5] from Amazonas, and Punos from the Andean highlands [PUNO, n = 9]) and 9 modern mestizos from Lima (LIM). Closed genomes and DNA modification calls were obtained using SMRT/PacBio sequencing. We performed evolutionary analyses and evaluated genomic/epigenomic differences among strain groups. We also evaluated human genome-wide data from 74 individuals from the selected Native communities (including the 23 H. pylori strains donors) to compare host and bacterial backgrounds. There were varying degrees of hspAmerind ancestry in all strains, ranging from 7% in LIM to 99% in SHIM. We identified three H. pylori subpopulations corresponding to each of the Native groups and a novel hspEuropePeru which evolved in the modern mestizos. The divergence of the indigenous H. pylori strains recapitulated the genetic structure of Native Americans. Phylogenetic profiling showed that Orthogroups in the indigenous strains seem to have evolved differentially toward epigenomic regulation and chromosome maintenance, whereas OGs in the modern mestizo (LIM) seem to have evolved toward virulence and adherence. The prevalence of cagA⁺/vacA s1i1m1 genotype was similar across populations (p = 0.32): 89% in ASHA, 67% in PUNO, 56% in LIM and 40% in SHIM. Both cagA and vacA sequences showed that LIM strains were genetically differentiated (p < 0.001) as compared to indigenous strains. We identified 642 R-M systems with 39% of the associated genes located in the core genome. We found 692 methylation motifs, including 254 population-specific sequences not previously described. In Peru, hspAmerind is not extinct, with traces found even in a heavily admixed mestizo population. Notably, our study identified three new hspAmerind subpopulations, one per Native group; and a new subpopulation among mestizos that we named hspEuropePeru. This subpopulation seems to have more virulence-related elements than hspAmerind. Purifying selection driven by variable host immune response may have shaped the evolution of Peruvian subpopulations, potentially impacting disease outcomes.

Particular Morphological Features in the Diagnosis of Pediatric Helicobacter pylori Gastritis: A Morphometry-Based Study

Background: Current pediatric guidelines recommend the use of the Updated Sydney Classification for gastritis to assess histological changes caused by Helicobacter pylori (H. pylori) infection. The purpose of this study was to investigate the morphometric alterations of the antral mucosa in relation to pediatric H. pylori infection. Methods: A total of 65 cases were considered eligible. Apart from scoring the biopsies according to the recommendations, foveolar hyperplasia (FH) was assessed. The following measurements were performed on digital slides: total mucosal thickness, foveolar and glandular length, number of glandular cross sections per 40X field, glandular diameter, and distance between glands. Results: The thickness of the antral mucosa increased along with the bacterial density and the intensity of inflammation in H. pylori-infected children (p < 0.05). FH was significantly associated with the presence of H. pylori (p < 0.001) and also exhibited a greater length of the foveolar and glandular structures and an increased glandular diameter (p < 0.05), but without influencing the thickness of the mucosa. Conclusions: Our results reinforce the fact that FH is not only an important histologic characteristic of gastropathy, but is also a significant change observed in H. pylori infection in children and may be considered for reporting when evaluating pediatric gastric biopsies.

Characteristics of Helicobacter pylori strains isolated from Mauritanian patients

BACKGROUND

Helicobacter pylori (H pylori) is responsible for various diseases including cancer It co-evolved with humans, and human migrations shaped the expansion and the diversity of strains around the world. The risk of developing a disease depends on virulence factors, mainly the cytotoxin-associated gene A protein (CagA). The aim of this study was to determine the cagA status in H pylori strains from Mauritanian patients and to search for a relationship with endoscopic and histologic findings.

MATERIAL AND METHODS

H pylori was searched in gastric biopsies taken during endoscopy in patients with gastro-duodenal symptoms. RT-PCR was used for the diagnosis and resistance to clarithromycin. The cagA status was determined with PCR and the EPIYA-cagA polymorphism with sequencing.

RESULTS

At all, 76/78 (97.4%) biopsies were positive. The rate of clarithromycin resistance was 4/76 (5.26%) due to the A2143G mutation, with a mixed population in 2 cases. The cagA gene was present in 23/76 (30.26%) biopsies, and the EPIYA motif was ABC in 21 (91.3%). High bacterial load and inflammation were significantly associated with cagA-positive status (P < .01). Phylogenetic analysis of the glmM and hspA genes highlighted a mixture of African and European genes in strains of H pylori isolated from patients of Moor origin.

CONCLUSION

We report a high prevalence of H pylori infection in Mauritanian patients, a low rate of clarithromycin resistance (5.26%) and high bacterial load and inflammation associated with cagA-positive status. The phylogenetic analysis highlights the mix of different populations leading to the Moor ethnicity.

Data-Driven Development of an Institutional "Gross-Only" Policy for the Examination of Select Surgical Pathology Specimens

OBJECTIVES

To determine diagnostic, workflow, and economic implications of instituting a gross-only policy at our institution.

METHODS

Retrospective (2017) key word searches were performed to identify "gross-only" cases for which microscopic evaluation could potentially be omitted, but was performed, and those who underwent gross evaluation per surgeon request. Cases were evaluated for type(s), part(s), block volume, turnaround time, demographics, and diagnosis. Laboratory costs and reimbursement were evaluated.

RESULTS

In total, 448 potential gross-only cases with 472 specimens consisted of atherosclerotic plaques (33.5%), bariatric stomach/bowel (32.6%), hernia (15.7%), heart valves (12.7%), and other (5.9%). Four (2.6%) bariatric surgery cases had Helicobacter pylori infection; these were the only cases with "significant" histologic findings. Cost analysis revealed that converting all potential gross-only specimens to gross only would result in overall losses based on average reimbursements, most influenced by bariatric specimens (Current Procedural Terminology code 88307), comprising 65.2% of estimated loss.

CONCLUSIONS

Establishing a gross-only policy should be guided by established recommendations but institutionally individualized and data driven. It was reasonable for us to establish a gross-only policy for most evaluated specimens, while excluding bariatric stomach specimens in which microscopic pathology could be missed, given the lack of H pylori screening at our institution.

Helicobacter pylori infection in children with celiac disease: Multi-center, cross-sectional study

BACKGROUND

An inverse association has been suggested between celiac disease (CD) and Helicobacter pylori (Hp) infection in children; however, there are inconsistent data. The purpose of this multi-center study is to evaluate the association between Hp and CD in childhood.

METHODS

Children who underwent endoscopy between July 2016 and November 2017 in four pediatric gastroenterology centers were included in the study. Patients with a history of previous Hp eradication, antibiotic or acid-suppressive drug therapy in the last 4 weeks, and any underlying chronic disease were excluded. The presence of Hp infection was confirmed by both histopathology and the rapid urease test. The ones who had the diagnosis of CD were compared with the children who underwent endoscopy during the same period and had another diagnosis. Duodenal histopathology of children with CD was categorized according to the modified Marsh classification.

RESULTS

Of 3056 endoscopies performed in the study period, 2484 cases were eligible for the study. A total of 482 CD patients (mean age: 9.71 ± 4.63 years, 58.5% girls) and 2060 controls (mean age: 9.92 ± 4.66 years, 54.6% girls) were included in the study. The rate of Hp infection was significantly lower in CD group (26.3% vs 50.1%, P < .01). The difference was prominent even in children younger than 6 years old (P < .01). There was no correlation between Hp infection and the modified Marsh scores in CD (P > .05).

CONCLUSION

In this cross-sectional study, where Hp infection is common even in the pediatric population, the frequency of Hp infection was significantly lower in children with CD compared with the controls. Systematic cohort studies are necessary to clarify causal association between Hp infection and the development of celiac disease.

Colonization by Pseudomonas aeruginosa and Staphylococcus aureus of Antral Biopsy Specimens from Gastritis Patients Uninfected with Helicobacter Pylori

Purpose

Roles and incidence of some microorganisms that transiently or permanently colonize the human stomach are still unknown despite advances in gastroenterology. We aimed to examine the incidence of four microorganisms, Helicobacter pylori, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis, in the antral biopsy specimens of patients with gastroduodenal conditions.

Patients and Methods

Patients (67 females, 33 males; mean age = 49.5 years) were initially examined and diagnosed by a gastroenterologist at the Mehrad Hospital, Tehran, Iran. We enrolled those who underwent the upper gastrointestinal endoscopy because of gastroduodenal conditions. Two antral biopsy samples were taken by endoscopy; the first sample was used for the “rapid urease test” to confirm H. pylori. The second was used for DNA extraction and PCR analyses with specific, corresponding primer sets to establish the presence of the four microorganisms. Our study was approved by the Ethics Committee at the Tarbiat Modares University, Tehran.

Results

Based on pathology and endoscopy findings, we divided the patients into three groups: 62 presented with gastritis, 18 with duodenal ulcer, and 20 gastric ulcer. The number of patients with P. aeruginosa but without H. pylori significantly differed from the number of those co-infected with both microorganisms (P = 0.03). Additionally, a similar significance was found between the incidence of S. aureus in patients without H. pylori and those with both infections (P = 0.04). Our results indicated that a significant number of patients with gastritis were colonized with P. aeruginosa or S. aureus without being co-infected with H. pylori (P < 0.001). Interestingly, the incidence of colonization by P. aeruginosa of patients without H. pylori (45/49, 91.8%) was higher than that by S. aureus (28/49, 57%).

Conclusion

The number of patients without H. pylori but with P. aeruginosa or with S. aureus infection significantly differed from that with both infections, respectively. Our study thus shows that patients without H. pylori infection are prone to be colonized by P. aeruginosa or S. aureus, indicating that targeted antibiotic regimens are necessary for clinically treating them.

Is the Utilization of Helicobacter pylori Stool Antigen Tests Appropriate in an Urban Canadian Population?

OBJECTIVES

Helicobacter pylori stool antigen test (HpSAT) appropriateness was investigated by assessing its testing and positivity rates in Calgary, Canada.

METHODS

The laboratory information system was accessed for all patients who received an HpSAT in 2018. Testing volume, test results, age, and sex of patients were collected. Sociodemographic risk factors and geospatial analysis were performed by matching laboratory data to the 2016 census data. Testing appropriateness was defined as a concordance between testing and positivity rates for each sociodemographic variable.

RESULTS

In 2018, 25,518 H pylori stool antigen tests were performed in Calgary, with an overall positivity rate of 14.7%. Geospatial mapping demonstrated significant distribution variations of testing and positivity rates of HpSAT in the city. Certain sociodemographic groups studied (eg, recent immigrants) appeared to be appropriately tested (testing rate relative risk [RR] = 2.26, positivity rate RR = 4.32; P < .0001), while other groups (eg, male) may have been undertested (testing rate RR = 0.85, positivity rate RR = 1.14; P < .0001).

CONCLUSIONS

Determining concordance of testing and positivity rate of a laboratory test can be used for assessing testing appropriateness for other diseases in other jurisdictions. This study demonstrated some at-risk patients may be missed for H pylori testing.

Association between infection and delayed growth in children: A meta-analysis

Helicobacter pylori (H. pylori) infection is associated with extra-gastrointestinal diseases in children. The present study aimed to investigate the potential association between H. pylori infection and growth in children. The PubMed, Exerpta Medica dataBASE, Cochrane Library and Chinese Biomedical Literature Database databases were comprehensively searched for relevant publications dated between January 1st 1994 and January 1st 2019. Delayed childhood growth was defined according to the age-appropriate criteria in the World Health Organization Child Growth Charts (2006 edition). The odds ratios (ORs) and 95% CIs were pooled using the fixed-effects model and subgroup and sensitivity analyses were performed using Review Manager (version 5.3; Cochrane) and STATA (version 12.0; StataCorp LP) software. A total of 15 observational studies comprising 4,199 subjects were included in the present study. A higher frequency of delayed growth was observed in H. pylori-positive children compared with that in H. pylori-negative children (OR, 1.51; 95% CI, 1.28-1.78), particularly for linear growth (OR, 1.63; 95% CI, 1.32-2.00). The aforementioned association was only observed when H. pylori infection was detected using ¹³C-urea breath tests (OR, 1.72; 95% CI, 1.22-2.40) or serum IgG antibodies targeted against H. pylori (OR, 1.81; 95% CI, 1.35-2.44). H. pylori infection was also associated with delayed childhood growth in studies with a H. pylori prevalence of ≤30% (OR, 1.71; 95% CI, 1.31-2.23) or >30% but not >50% (OR, 1.43; 95% CI, 1.10-1.86). The association between infection and growth was only statistically significant in the cross-sectional (OR, 1.43; 95% CI, 1.18-1.73) and case-control (OR, 1.81; 95% CI, 1.23-2.67) studies. No significant heterogeneity among studies was identified in the present analysis. According to Begg's and Egger's linear regression methods for funnel plots and quantification assessments, no publication bias was identified. The trim and fill method further suggested that H. pylori-positive children were prone to delayed linear growth. Therefore, the present study suggested that preventing and detecting H. pylori infection in children may be critical to ensure normal growth and development during childhood.

Dental problems and chronic diseases in mentally ill homeless adults: a cross-sectional study

Background

Dental problems (DPs) and physical chronic diseases (CDs) are highly prevalent and incident in people with low socioeconomic status such as homeless individuals. Yet, evidence on the association between DPs and physical CDs in this population is limited. In the present study, we assessed the association between DPs and type and number of CDs in individuals experienced chronic homelessness and serious mental health problems.

Methods

We analyzed cross-sectional baseline data from 575 homeless adults with serious mental health problems participating in the Toronto site of the At Home/Chez Soi randomized controlled trial. Chronic DPs (lasting at least 6 months) were the primary exposure variable. Presence of self-reported CDs, including heart disease, effect of stroke, hypertension, diabetes, asthma, chronic bronchitis/emphysema, stomach or intestinal ulcer, inflammatory bowel disease, migraine, thyroid problems, arthritis, kidney/bladder problems, liver disease (other than hepatitis), and iron-deficiency anemia, were the primary outcomes. The total number of CDs was also analyzed as a secondary outcome.

Logistic regression models were used to assess the association between DPs with each of the studied CDs, and negative binomial regression was used to test the association between DPs with the number of CDs.

Results

In our 575 homeless participants (68.5% males) with mean age 40.3 (11.8) years, a high proportion had DPs (42.5%). The presence of DPs was positively associated with heart disease (adjusted odds ratio (AOR):4.19,1.67–10.52), diabetes (AOR:2.17,1.13–4.17), chronic bronchitis (AOR:2.34,1.28–4.29), stomach or intestinal ulcer (AOR:3.48,1.80–6.73), inflammatory bowel disease (AOR:2.52,1.38–4.60), migraine (AOR:1.80,1.20–2.72), arthritis (AOR:2.71,1.71–4.29), kidney/bladder problems (AOR:2.43,1.30–4.54), and iron-deficiency anemia (AOR:3.28,1.90–5.65). DPs were also associated with a higher number of CDs (IRR: 1.62,1.38–1.90).

Conclusion

Dental health problems in homeless individuals with serious mental disorders are associated with several CDs. Dental care should be better integrated into existing social and health programs serving this population to improve their overall health status.

The AH/CS study is registered with the International Standard Randomized Control Trial Number Register (ISRCTN42520374).

Helicobacter pylori Gastritis in Children-The Link between Endoscopy and Histology

Background: The management of Helicobacter pylori (H. pylori) infection raises important challenges, still being the most common chronic infection worldwide in all age groups. In high-prevalence regions, paediatric patients need a specific focus, as the acquisition of the infection takes place in childhood. The objective of this study was to analyze the endoscopic and histopathologic changes of the gastric mucosa in H. pylori infected children. Material and Methods: A retrospective study was performed on consecutive paediatric patients, ranging from 0 to 18 years of age, who underwent an upper gastrointestinal endoscopy (UGE) for a period of 5 years, regardless of their symptomatology. Endoscopy reports and histological slides were reviewed and clinical, endoscopic, and histologic data were recorded. Results: A total of 248 patients were included in the study, 82 (33.06%) of them being H. pylori infected. There was no difference in age and symptoms between the infected and noninfected group. A significant association was found between the H. pylori infection and histopathological parameters such as acute and chronic inflammatory infiltrate. The bacterial load influences the intensity of inflammation (p < 0.001). The chronic inflammation was predominant, only 23.2% of the patients displayed acute inflammation (p < 0.0001). The topographic distribution of inflammation was dominated by pangastritis (p = 0.04) with 58.6% of the patients presenting similar degrees of inflammation both in the antrum and corpus. Conclusion: Endoscopic features such as nodularity of the antral mucosa (p < 0.05) along with histological findings as lymphoid follicles (p < 0.05) are suggestive of H. pylori infection. However, the concordance between the endoscopic and histological diagnosis is still far from perfect (Cohen’s k coefficient = 0.42), maintaining the need for an invasive approach in children.

Risk factors for gastric precancerous and cancers lesions in Latin American counties with difference gastric cancer risk

OBJECTIVE

To evaluate the risk factors associated with pre-neoplastic lesions and gastric cancer in countries with different cancer risk in Latin America.

METHODS

1222 questionnaires of risk factors related to pre-neoplastic lesions and gastric cancer were obtained from patients from Mexico (N = 559), Colombia (N = 461) and Paraguay (N = 202), who were treated at the gastroenterology or oncology service of participant hospitals. In addition, biopsies specimens to establish histological diagnosis and blood to detect IgG antibodies against Helicobacter-pylori (H. pylori) whole-cell antigens and CagA protein using an ELISA were collected. These consisted of 205 gastric cancer, 379 pre-neoplastic (intestinal metaplasia (IM) / atrophic gastritis) and 638 control (normal /non-atrophic gastritis) cases. The odds ratio (OR) and 95% confidence intervals (CI) associated with potential risk factors were estimated by polynomial logistic regression model.

RESULTS

Seropositivity to H. pylori was associated with risk of pre-neoplastic lesions, with OR = 1.9 (CI 95% 1.2-2.9; p = 0.006). Grain / cereal intake (OR = 1.6, 95% CI 1.0-2.5 ; p = 0.049) and egg intake (OR = 1.7 95% CI 1.1-2.6 ; p = 0.021) were related to gastric cancer. Among, people who did not developed gastric cancer, smoking more than five cigarette per day had the highest risk of being infected by H. pylori (OR = 1.9; CI 95% 1.1-3.3 ; p = 0.028).

CONCLUSION

The present study in Latin American countries confirmed that similar environmental factors such as smoking and grain/cereal consumption were associated with H. pylori infection and its induced gastric lesions as reported in other regions where dominant H. pylori strains differ.

Helicobacter pylori Infection, Virulence Genes' Distribution and Accompanying Clinical Outcomes: The West Africa Situation

Data on Helicobacter pylori (H. pylori) infection and virulence factors in countries across West Africa are scattered. This systematic review seeks to present an update on the status of H. pylori infection focusing on prevalence rate, distribution of virulent genes, and their link to clinical outcomes across countries in the western part of Africa. This information is expected to broaden the knowledge base of clinicians and researchers regarding H. pylori infection and associated virulence factors in West African countries. Search Method. A comprehensive search of the scientific literature in PubMed and ScienceDirect was conducted using the search terms including “Helicobacter pylori infection in West Africa”. Databases were sourced from January 1988 to December 2018. Results. Data on the incidence of H. pylori infection and related pathological factors were found for some countries, whereas others had no information on it. Smoking, alcohol, exposure to high levels of carcinogens and diet were reported to be involved in the pathogenesis of gastroduodenal diseases and gastric cancer. Besides the environmental factors and genetic characteristics, there are important characteristics of H. pylori such as the ability to infect, replicate, and persist in a host that have been associated with the pathogenesis of various gastroduodenal diseases. Concluding Remarks. This systematic search has provided information so far available on H. pylori virulence factors and clinical outcomes in West Africa. Accordingly, this piece has identified gaps in the body of knowledge highlighting the need for more studies to clarify the role of H. pylori virulence factors and associated clinical outcomes in the burden of this bacterial infection in West Africa, as data from these countries do not give the needed direct relation.

Phylogenetic analysis of clinical strains of Helicobacter pylori isolated from patients with gastric diseases in Tibet

BACKGROUND

Helicobacter pylori (H. pylori) is a Gram-negative pathogenic bacterium that causes chronic gastritis and other gastric diseases in humans. In Tibet, China, the infection of H. pylori is an important risk factor that caused gastric cancer.

METHODS

To understand the characteristics of this pathogen in Tibet, five strains of H. pylori were isolated from three patients' oral cavity or stomach who had either a gastric ulcer or gastritis. We performed genome sequences of these five clinical strains on Illumina Hiseq, and 55,016-63666 SNVs/InDels were identified by comparing to the reference strain of H. pylori 26995.

RESULTS

The phylogenetic analysis with multi-locus sequence typing (MLST) showed that five Tibetan strains were defined as hpEurope population and their proteins encoded by the cagA gene also presented a western type. Also, the strains that were isolated from the same patients' oral cavity and stomach exhibited homology in molecular evolution.

CONCLUSIONS

This is the first study to investigate the phylogenetic population structure of the epidemic strains of H. pylori in Tibet, which may improve cognition of Tibetan strains and confirm the homology of the strains from oral cavity and stomach.

Potential transmission sources of Helicobacter pylori infection: detection of H. pylori in various environmental samples

PURPOSE

Helicobacter pylori is one of the most common human infectious agents which may be transmitted via water. This study was designed to test H. pylori presence via molecular methods in various aquatic environments as well as sewage sludge (SS) to understand the role of these environments in the pathogen's transmission.

METHODS

specific primers for the 16S rRNA and ureA genes of H. pylori were used in a nested and semi-nested PCR, respectively. Detection sensitivity of H. pylori in environmental samples by semi-nested PCR was also compared with real-time PCR. Analysis of fecal coliforms (FC) as pollution indicator bacteria was also performed.

RESULTS

H. pylori 16S rRNA gene was detected in 36% (14/39) of wastewater samples and 8% (2/25) of water samples, while amplification of ureA gene yielded only two positive results. None of the SS samples were positive for H. pylori and real-time PCR could not identify H. pylori in any of the samples. The results showed no correlation between the presence of H. pylori and FC.

CONCLUSIONS

Our result revealed the widespread presence of H. pylori in wastewater samples which indicates wastewater may be a source for dissemination and transmission of H. pylori infection. Further research is needed to determine the risk of H. pylori in wastewater reuse for irrigation of crops.

TIME TRENDS OF HELICOBACTER PYLORI PREVALENCE IN ITAJAÍ - SC: A RETROSPECTIVE STUDY OF 25 YEARS BASED ON ENDOSCOPIC DATABASE

BACKGROUND

The bacterium Helicobacter pylori is strongly associated with the development of gastric adenocarcinoma. Currently, the prevalence in developed countries is 40%, but this value increases considerably in developing countries, which can reach rates bigger than 90%.

OBJECTIVE

The objective of this study was to determine the mean and annual prevalence of Helicobacter pylori infection in patients from Itajaí during the period from July 1992 to April 2016, as well as the gender and age groups most affected.

METHODS

After consent of the clinical director of the Gastroclinica Itajaí and confidentiality commitment about the research, the database of the Endoscopy Service of the clinic was evaluated. All the patients who underwent their first upper digestive endoscopy with urease test and/or histological analysis were included. The data were submitted to statistical analysis of prevalence by gender, age group and years of study, with subsequent correction through the confidence interval.

RESULTS

The mean prevalence of Helicobacter pylori infection thru all years of study was 50.07%. With the calculation of the annual prevalences, it was evident the gradual reduction of infection in the population of Itajaí, that was 81.3% in 1992, declining to 33% in the year of 2016. When classifying the prevalence of infection by gender, it was higher in males (53.59%), and gender distribution by age group showed no statistically significant difference among genders between the ages of 40 and 80 years. In relation to the age group, the highest prevalence was in the group between 40 and 49 years.

CONCLUSION

Although this study is retrospective and based on endoscopic database analysis, without access to clinical data of patients such as prior use of proton pump inhibitor and antibiotics to endoscopy, its results are important because they may reflect the current panorama of Helicobacter pylori infection in the city under study, where it has been presenting a gradual reduction of prevalence over the years, with current rates similar to that of developed countries (33%). Future studies are needed to confirm our data.

Molecular evolution of the VacA p55 binding domain of Helicobacter pylori in mestizos from a high gastric cancer region of Colombia

The stomach bacterium Helicobacter pylori is one of the most prevalent pathogens in humans, closely linked with serious diseases such as gastric cancer. The microbe has been associated with its host for more than 100,000 years and escorted modern humans out of Africa. H. pylori is predominantly transmitted within families and dispersed globally, resulting in distinct phylogeographic patterns, which can be utilized to investigate migrations and bioturbation events in human history. Latin America was affected by several human migratory waves due to the Spanish colonisation that drastically changed the genetic load and composition of the bacteria and its host. Genetic evidence indicates that independent evolutionary lines of H. pylori have evolved in mestizos from Colombia and other countries in the region during more than 500 years since colonisation. The vacuolating cytotoxin VacA represents a major virulence factor of the pathogen comprising two domains, p33 and p55, the latter of which is essential for binding to the host epithelial cell. The evolution of the VacA toxin in Colombia has been strongly biased due to the effects of Spanish colonization. However, the variation patterns and microevolution of the p55 domain have not yet been described for this population. In the present study, we determined the genetic polymorphisms and deviations in the neutral model of molecular evolution in the p55 domain of 101 clinical H. pylori isolates collected in Bogotá, a city located in Andean mountains characterized by its high gastric cancer risk and its dominant mestizo population. The microevolutionary patterns of the p55 domain were shaped by recombination, purifying and episodic diversifying positive selection. Furthermore, amino acid positions 261 and 321 in the p55 domain of VacA show a high variability among mestizos clinical subsets, suggesting that natural selection in H. pylori may operate differentially in patients with different gastric diseases.

The Diagnostic Tests for Detection of Helicobacter pylori Infection

Helicobacter pylori causes one of the most common infections in human populations. The role of this bacterium in chronic gastritis, gastric ulcer, gastric cancer, as well as extra-digestive diseases such as ischemic heart disease and chronic obstructive pulmonary diseases, is well known. Prevention and control of these diseases can occur by early diagnosis and eradication of H. pylori infection. At present, different methods have been established to detect H. pylori infection. The biopsy-based tests, which are known as invasive methods, such as rapid urease test and histology, have the highest specificity among the others. Similarly, culture of biopsy samples is used for diagnosis of H. pylori infection. It has a high specificity value, and also allows us to perform antibiotic sensitivity testing. On the contrary, polymerase chain reaction and other molecular methods have good sensitivity and specificity, and can be used for detection of H. pylori infection, its virulence factors, and eradication success after treatment. While serological tests are more appropriate for epidemiological studies, their main weakness for clinical use is low specificity. Overall, specificity and sensitivity, cost, usefulness, and limitation of tests should be considered for selection of detection methods of H. pylori in each country.

Etiologic and Clinicopathological Correlates of Gastric Carcinoma in the Egyptian Delta

We aimed at evaluation of the clinicoepidemiologic data of patients with gastric carcinoma in the Egyptian Delta as regards the etiologic factors, behavior, presenting symptoms, and tumor location, grade, and stage with highlighting of the treatment modalities, survival, and prognostic factors. Three hundred cases with gastric carcinoma were enrolled, diagnosed, and treated in a tertiary oncology center in the Egyptian Delta. Data were collected as regards the etiology, presenting symptoms, family history, comorbid conditions, treatment modalities, responses, recurrences, and survival outcomes. Univariate and multivariate analyses were done to correlate the different clinicopathologic factors with the overall and disease-free survivals. Male to female ratio was 2:1. The median age was 43 years. The main tumor location was in the gastric body. Pain was the commonest presenting symptom (36%). Most of the cases were stage IV (42.0%). Only 49% of cases were operable. On multivariate analysis, age more than 60 years, performance status 3-4, high grade, diffuse type, T4 lesions, N2 and N3, and the presence of metastasis were independently associated with worse OS. We report a clinic-epidemiologic study of gastric carcinoma in the Egyptian delta; the age at presentation was a decade earlier than that recorded in the USA and Europe; most of the cases were sporadic, located mostly at the body. Most of the cases were presented at stage IV with poor response to neoadjuvant therapy with a poorer overall survival than that recorded in the USA and Europe.

Accounting for Bacterial Overlap Between Raw Water Communities and Contaminating Sources Improves the Accuracy of Signature-Based Microbial Source Tracking

Microbial source tracking (MST) analysis is essential to identifying and mitigating the fecal pollution of water resources. The signature-based MST method uses a library of sequences to identify contaminants based on operational taxonomic units (OTUs) that are unique to a certain source. However, no clear guidelines for how to incorporate OTU overlap or natural variation in the raw water bacterial community into MST analyses exist. We investigated how the inclusion of bacterial overlap between sources in the library affects source prediction accuracy. To achieve this, large-scale sampling - including feces from seven species, raw sewage, and raw water samples from water treatment plants - was followed by 16S rRNA amplicon sequencing. The MST library was defined using three settings: (i) no raw water communities represented; (ii) raw water communities selected through clustering analysis; and (iii) local water communities collected across consecutive years. The results suggest that incorporating either the local background or representative bacterial composition improves MST analyses, as the results were positively correlated to measured levels of fecal indicator bacteria and the accuracy at which OTUs were assigned to the correct contamination source increased fourfold. Using the proportion of OTUs with high source origin probability, underpinning a contaminating signal, is a solid foundation in a framework for further deciphering and comparing contaminating signals derived in signature-based MST approaches. In conclusion, incorporating background bacterial composition of water in MST can improve mitigation efforts for minimizing the spread of pathogenic and antibiotic resistant bacteria into essential freshwater resources.

Prevalence of Helicobacter pylori in asymptomatic patients at surgical outpatient department: Harare hospitals

Background

Helicobacter pylori infection is present in more than 50% of the world's population. The estimated life time risk of peptic ulcer disease is 20 percent and of gastric cancer is 1–2 percent.

Materials and methods

A cross sectional study was done at two Central hospitals in Harare, Zimbabwe, with the objective being to estimate the prevalence of Helicobacter pylori infection in asymptomatic individuals. Other objectives were to determine the association of the Helicobacter pylori infection with potential risk factors.

Four hundred and fifty patients visiting the outpatient surgical clinics for other complaints other than upper gastrointestinal symptoms were recruited in the study. Drops of whole blood were obtained by fingertip puncture from each patient. The Onsite H. pylori Combo Rapid Test was used to confirm the presence or absence of antibodies against Helicobacter pylori. A questionnaire was used to record the sociodemographics of the participants.

Results

Three hundred patients, 186 males (62%) and 114 females (38%) participated. The prevalence of Helicobacter pylori infection was 67.7 percent (203/300). The prevalence of H pylori infection was significantly correlated with increasing age (p = 0.012), sharing of a bed with siblings during childhood (p = 0.013) and the mode of sanitation methods (p = 0.023). There was no association found between H pylori infection and other risk factors such as; gender, level of education, employment status or number of rooms in a house.

Conclusion

H. pylori infection prevalence was significantly associated with increasing age, sharing of a bed with siblings during childhood and the mode of sanitation used. Clinicians and the public have to be aware of the important role of H pylori in upper gastrointestinal disease. Use of better sanitation methods, appropriate hygiene, avoidance of over-crowding amongst other measures should be encouraged as a means to reduce the acquisition and transmission of H pylori.

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Prevalence of H. pylori infection is 67.7%.

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The results are from Zimbabwe.

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It is associated with increasing age and the mode of sanitation.

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It is associated with sharing of a bed with siblings during childhood.

First-time serological and molecular detection of Helicobacter pylori in milk from Algerian local-breed cows

AIM

The present study was conducted to detect and identify Helicobacter pylori within local cow breeds in the central region of Algeria.

MATERIALS AND METHODS

Two hundred (n=200) cows from three provinces of the central region of Algeria were studied, between January 2016 and September 2017. Each cow was subject to stool, milk, and blood sampling. Milk and fecal samples were used to detect and identify H. pylori using bacteriology culture method. Blood and milk samples were used to detect H. pylori immunoglobulin G (IgG) antibody using enzyme-linked immunosorbent assay. Polymerase chain reaction was used to confirm the abundance of H. pylori in milk by detecting glmM gene.

RESULTS

Out of 200 sera and 200 milk samples, 12% (24) and 4% (8/200) were positive for the H. pylori IgG antibody. glmM gene was detected in the milk of 13% of cows and was confirmed in all cows presenting IgG in milk.

CONCLUSION

From the present study, we concluded that the glmM gene is an important marker for detecting H. pylori in milk. Moreover, Algerian local-breed cows are a source of H. pylori and could be responsible for serious zoonosis.

Unpacking Hispanic Ethnicity-Cancer Mortality Differentials Among Hispanic Subgroups in the United States, 2004-2014

Introduction: National data on the epidemiology of cancer are commonly reported by broad racial/ethnic categories, such as "Hispanic." However, few studies have disaggregated Hispanic groups and explored mortality differentials in this heterogeneous population. This paper aims to further examine cancer mortality differentials among Hispanic subgroups in the U.S. Materials and Methods: The study examined cancer deaths in the United States from 2004 to 2014 among decedents classified as Mexican, Puerto Rican, Cuban, Dominican, Central/South American and non-Hispanic white on the death certificate among those who were 20 years or older at the time of death. Data were obtained from the National Vital Statistics System. Sex-specific age-adjusted mortality rates were computed for a 10-year period and each individual year, for all cancers combined. Differences by age group, cancer sites, and age distribution were also assessed. Results: A total of 296,486 Hispanic cancer deaths were identified. Mortality rates of the Hispanic subgroups compare favorably with those of non-Hispanic whites. The mortality rates for Mexicans are very similar to those of all Hispanics combined, whereas the rates for Cuban and Puerto Ricans are higher. Dominicans and Central/South Americans had the overall lowest mortality rates. Statistically significant decreases in cancer mortality rates were noted in some sub-groups, but rates increased among Dominican women. Age-adjusted mortality rates by cancer site varied among Hispanics subgroups and gender. Among Cubans, only 5% of cancer deaths occurred before the age of 50 compared to 16% of cancer deaths among Central/South American. Conclusion: While it is common to present data on the burden of cancer among Hispanics as an aggregate group, this study illustrates that the burden of cancer varies by Hispanic subgroups. The disaggregation of Hispanics by ancestry/country of origin allows for a clearer understanding of the health status of this growing population and is needed if health disparities are to be adequately identified, understood and addressed.

Magnitude of Helicobacter pylori among Dyspeptic Patients Attending at University of Gondar Hospital, Gondar, Northwest Ethiopia

Background

Helicobacter pylori (H.pylori) infection is predominantly acquired in childhood from family members. The infection can cause dypepepsia, chronic and acute gastritis and gastric cancer. Dyspepsia is the most common illness in the Ethiopian population visiting outpatient department of health facilities, and it has also been associated with H.pylori infection. The aim of this study was to assess the magnitude of H.pylori and its associated factors among dyspeptic patients who visited University of Gondar Hospital Outpatient Department.

Materials and Methods

An institutional-based cross-sectional study was conducted on 354 dyspeptic patients. A systematic random sampling technique was employed to select study participants. Data were collected by using structured questionnaire via face-to-face interview. H.pylori infection was diagnosed using stool antigen test method. The data were entered into Epi info version 3.5.3 and transferred to Statistical Package for Social Sciences version 20. Both Bivariable and multivariable binary logistic regression analyses were performed to see the effect of independent variables on the dependent variable.

Result

Of the total study participants, 201(56.8%), 195(55.1%) and 182(51.4%) were married, urban residents and females, respectively. The overall magnitude of H.pylori infection was 37.6%. In bivariable logistic regression analysis, sex and marital status were significantly associated with H.pylori infection, but in multivariable logistic regression analysis only marital status was significantly associated with H.pylori infection.

Conclusion

The magnitude of H.pylori infection is high indicating that it is a public health problem in the study to area. According to this study, none of the variables were significantly associated with H.pylori infection. Hence, effective preventive, control and screening strategies need to be designed to reduce the burden of the disease.

Prevalence of CagA and antimicrobial sensitivity of H. pylori isolates of patients with gastric cancer in Egypt

BACKGROUND

Helicobacter pylori (H. pylori) infection has been recognized as a significant threat for gastric cancer. However, studies that investigated the oncogenic factors and antimicrobial resistance of H. pylori in Egyptian isolates with gastric cancer are rare. The current study aimed to examine: (1) The pattern of antimicrobial resistance of H. pylori isolates of Egyptian gastric cancer patients, and (2) the prevalence of Cytotoxin-associated gene A (CagA).

METHODS

Samples were collected from patients with gastric cancer. Isolation of H. pylori was performed using Columbia blood agar supplemented with 10% horse blood, and selective supplement of H. pylori for 3 to 5 days at 37 °C under microaerophilic condition. Isolates were identified by biochemical traits of H. pylori: oxidase, urease and catalase tests. Antimicrobial susceptibility of H. pylori isolates was examined against five antimicrobial agents using disc diffusion method. After that, extraction of DNA and Polymerase Chain Reaction (PCR) were performed to amplify the target genes.

RESULTS

Twelve samples were collected from six males and six females Egyptian patients with cancer with an age range from 22 to 65 years. These cases are scarce and samples were collected over a period of almost eleven months. All isolates were confirmed as positive H. pylori through colony morphology and biochemical tests. The most effective antibiotic found was ciprofloxacin whereas all isolates showed resistance to metronidazole and erythromycin. The target CagA oncogene gene with expected product size was reported and seven (out of twelve) isolates (58%) were identified as CagA positive.

CONCLUSION

The current study is unique in two main aspects. First, it reported the pattern of antimicrobial susceptibility and prevalence of CagA gene in H. pylori from Egyptian patients. Second, it exclusively recruited isolates from gastric cancer patients which were confirmed by clinical and laparoscopic examination. The moderately high prevalence of CagA gene in Egyptian cancer patients calls for more vigilance against that oncogene.

Rapid evolution of the Helicobacter pylori AlpA adhesin in a high gastric cancer risk region from Colombia

To be able to survive, Helicobacter pylori must adhere to the gastric epithelial cells of its human host. For this purpose, the bacterium employs an array of adhesins, for example, AlpA. The adhesin AlpA has been proposed as a major adhesin because of its critical role in human stomach colonization. Therefore, understanding how AlpA evolved could be important for the development of new diagnostic strategies. However, the genetic variation and microevolutionary patterns of alpA have not been described in Colombia. The study aim was to describe the variation patterns and microevolutionary process of alpA in Colombian clinical isolates of H. pylori. The existing polymorphisms, which are deviations from the neutral model of molecular evolution, and the genetic differentiation of the alpA gene from Colombian clinical isolates of H. pylori were determined. The analysis shows that gene conversion and purifying selection have shaped the evolution of three different variants of alpA in Colombia.

Is There a Role for the Non-Helicobacter pylori Bacteria in the Risk of Developing Gastric Cancer?

Helicobacter pylori is the most abundant bacterium in the gastric epithelium, and its presence has been associated with the risk of developing gastric cancer. As of 15 years ago, no other bacteria were associated with gastric epithelial colonization; but thanks to new methodologies, many other non-H. pylori bacteria have been identified. It is possible that non-H. pylori may have a significant role in the development of gastric cancer. Here, we discuss the specific role of H. pylori as a potential trigger for events that may be conducive to gastric cancer, and consider whether or not the rest of the gastric microbiota represent an additional risk in the development of this disease.

Dietary habits and Helicobacter pylori infection: a cross sectional study at a Lebanese hospital

BACKGROUND

To examine the association between dietary habits and Helicobacter pylori (H. pylori) infection among patients at a tertiary healthcare center in Lebanon.

METHODS

This cross-sectional study was conducted on 294 patients in 2016, at a hospital in Northern Lebanon. Participants were interviewed using a structured questionnaire to collect information on socio-demographic and lifestyle characteristics; dietary habits were ascertained via a short food frequency questionnaire (FFQ). H. pylori status (positive vs. negative) was determined after upper GI endoscopy where gastric biopsy specimens from the antrum, body, and fundus region were collected and then sent for pathology analysis. Multivariable logistic regression was conducted to identify the association between socio-demographic, lifestyle, dietary and other health-related variables with H pylori infection.

RESULTS

The prevalence of H. pylori infection was found to be 52.4% in this sample. Results of the multivariable analysis showed that H. pylori infection risk was higher among participants with a university education or above (OR = 2.74; CI = 1.17-6.44), those with a history of peptic ulcers (OR = 3.80; CI = 1.80-8.01), gastric adenocarcinoma (OR = 3.99; CI = 1.35-11.83) and vitamin D level below normal (OR = 29.14; CI = 11.77-72.13). In contrast, hyperglycemia was protective against H. pylori (OR = 0.18; CI = 0.03-0.89). No relationship between dietary habits and H. pylori infection was found in the adjusted analysis.

CONCLUSIONS

Socio-demographic and clinical variables are found to be associated with H. pylori, but not with dietary factors. Further studies are needed to investigate the effect of diet on H. pylori risk.

The fraction of cancer attributable to modifiable risk factors in England, Wales, Scotland, Northern Ireland, and the United Kingdom in 2015

BACKGROUND

Changing population-level exposure to modifiable risk factors is a key driver of changing cancer incidence. Understanding these changes is therefore vital when prioritising risk-reduction policies, in order to have the biggest impact on reducing cancer incidence. UK figures on the number of risk factor-attributable cancers are updated here to reflect changing behaviour as assessed in representative national surveys, and new epidemiological evidence. Figures are also presented by UK constituent country because prevalence of risk factor exposure varies between them.

METHODS

Population attributable fractions (PAFs) were calculated for combinations of risk factor and cancer type with sufficient/convincing evidence of a causal association. Relative risks (RRs) were drawn from meta-analyses of cohort studies where possible. Prevalence of exposure to risk factors was obtained from nationally representative population surveys. Cancer incidence data for 2015 were sourced from national data releases and, where needed, personal communications. PAF calculations were stratified by age, sex and risk factor exposure level and then combined to create summary PAFs by cancer type, sex and country.

RESULTS

Nearly four in ten (37.7%) cancer cases in 2015 in the UK were attributable to known risk factors. The proportion was around two percentage points higher in UK males (38.6%) than in UK females (36.8%). Comparing UK countries, the attributable proportion was highest in Scotland (41.5% for persons) and lowest in England (37.3% for persons). Tobacco smoking contributed by far the largest proportion of attributable cancer cases, followed by overweight/obesity, accounting for 15.1% and 6.3%, respectively, of all cases in the UK in 2015. For 10 cancer types, including two of the five most common cancer types in the UK (lung cancer and melanoma skin cancer), more than 70% of UK cancer cases were attributable to known risk factors.

CONCLUSION

Tobacco and overweight/obesity remain the top contributors of attributable cancer cases. Tobacco smoking has the highest PAF because it greatly increases cancer risk and has a large number of cancer types associated with it. Overweight/obesity has the second-highest PAF because it affects a high proportion of the UK population and is also linked with many cancer types. Public health policy may seek to mitigate the level of harm associated with exposure or reduce exposure levels-both approaches may effectively impact cancer incidence. Differences in PAFs between countries and sexes are primarily due to varying prevalence of exposure to risk factors and varying proportions of specific cancer types. This variation in turn is affected by socio-demographic differences which drive differences in exposure to theoretically avoidable 'lifestyle' factors. PAFs at UK country level have not been available previously and they should be used by policymakers in devolved nations. PAFs are estimates based on the best available data, limitations in those data would generally bias toward underestimation of PAFs. Regular collection of risk factor exposure prevalence data which corresponds with epidemiological evidence is vital for analyses like this and should remain a priority for the UK Government and devolved Administrations.