The Prevalence of Helicobacter pylori Infection Decreases with Older Age in Atrophic Gastritis

Endoscopic mucosal phenotypes and endoscopic Sydney system gastritis assessment in relation to Helicobacter pylori infection and upper digestive clinical signs: A 2-year study among patients with gastroduodenal disorders in Cameroon

Background and Aim

Helicobacter pylori represents the major pathogen in the pathophysiology of diverse gastrointestinal conditions. This study sought to determine the endoscopic aspect of the gastric mucosa in relation to H. pylori infection in Cameroon.

Methods

This study was conducted in three reference health facilities in Cameroon from October 2020 to October 2022. The study enrolled 494 consecutive volunteer dyspeptic patients attending to the gastroenterology department of the selected health facilities. A description of the aspect of gastric mucosa of all participants was performed during endoscopy examination, and biopsies were collected for H. pylori detection using rapid urease tests.

Results

Gastritis, ulcerated lesions, duodenitis, esophagitis, normal mucosa aspect, bulbitis, and gastric neoplastic lesions were found in 40.1, 22.3, 10.9, 10.3, 9.7, 6.3, and 0.40% of biopsy samples, respectively. Erythematous/exudative (45.9%) and enterogastric reflux (12.2%) were the main gastritis types recorded. H. pylori was present in 58.1, 46.3, 87.1, 66.7, and 61.8% in gastritis, duodenitis, bulbitis, esophagitis, and ulcerated lesions, respectively. A positive relationship was noticed between the presence of H. pylori and gastritis (1.037 [0.720-1.493]; P = 0.845), bulbitis (4.237 [1.602-11.235]; P = 0.004), esophagitis (1.515 [0.822-2.793]; P = 0.183), ulcerated lesions (1.233 [0.798-1.904]; P = 0.345), erythematous/exudative gastritis (1.354 [0.768-2.389]; P = 0.295), and enterogastric reflux gastritis (1.159 [0.492-2.733]; P = 0.736).

Conclusion

Gastritis and erythematous/exudative gastritis are the most frequent gastrointestinal pathophysiology conditions in dyspeptic patient in our milieu. H. pylori infection is responsible for 94.8% of the gastrointestinal pathophysiology conditions with bulbitis as the condition is significantly associated with this bacterium infection.

Impact of Helicobacter pylori eradication on the gastric microbiome

BACKGROUND

Helicobacter pylori (Hp) eradication has been used for many years. Yet, the impact of this eradication on the normal gastric microflora is not well understood. In this study, we explored the effect of eradication on the stomach microbial community and its recovery after successful Hp eradication.

METHODS

Among the 89 included patients, 23, 17, 40, and 9 were included in the Hp-negative, Hp-positive, successful eradication, and failed eradication groups, respectively. Four subgroups were further determined according to disease status (Hp-negative chronic gastritis [N-CG], Hp-negative atrophic gastritis [N-AG], successful-eradication chronic gastritis [SE-CG], and atrophic gastritis with successful eradication [SE-AG]). During the endoscopic examination, one piece of gastric mucosa tissue was obtained from the lesser curvature side of the gastric antrum and gastric corpus, respectively. In addition, 16S rDNA gene sequencing was used to analyze the gastric mucosal microbiome.

RESULTS

In the Hp-negative group, the gastric microbiota was dominated by five phyla: Firmicutes, Proteobacteria, Actinobacteria, Bacteroidetes, and Fusobacteria. After successfully eradicating Hp, the bacterial flora in the stomach recovered to a considerable extent. In the failed eradication group, the flora was similar to the flora in Hp-positive subjects based on the alpha and beta diversities. Among the groups, Curvibacter and Acinetobacter were enriched in the presence of Hp (i.e., failed eradication and Hp-positive groups), suggesting that these two genera could be used as biomarkers in the symbiotic flora in the presence of Hp. SE-CG was characterized by an increase in Firmicutes taxa and a decrease in Proteobacteria taxa compared with N-CG. SE-AG was characterized by a decrease in Firmicutes relative to N-AG. Finally, no differences were found in the pairwise comparisons of nitrate and nitrite reductase functions of the microflora among the four subgroups.

CONCLUSIONS

After Hp infection, the diversity and relative abundance of gastric microflora were significantly decreased. Yet, gastric microbiota could be partially restored to the Hp-negative status after eradication. Still, this effect was incomplete and might contribute to the long-term risks.

Prevalence and Potential Risk Factors of Helicobacter pylori Infection among Asymptomatic Individuals in Kazakhstan

BACKGROUND

Helicobacter pylori (H. pylori) infection is associated with several risk factors such as demographic, socioeconomic status and personal habits, which vary in different populations. This is the most up-to-date data on H. pylori prevalence and potential risk factors for H. pylori infection among asymptomatic middle-aged individuals in Kazakhstan.

METHODS

Apparently healthy individuals aged 40 to 64, who took part in the health control in the outpatient clinic, were invited to participate in the study; answered a questionnaire, donated a blood sample. The antibodies to H. pylori were analysed by latex agglutination method. The baseline characteristics of study subjects with or without H. pylori infection were compared using the Chi-square test. Odds ratio (OR) and 95% confidence intervals (CI) for the association between H. pylori infection and potential risk factors were estimated using multivariable logistic regression models.

RESULTS

Altogether 166 subjects (59% male; the median age - 51 years old) were included; 104 (62.7%) were H. pylori positive. There were no statistically significant differences between H. pylori positive and H. pylori negative groups in respect to the gender, anthropometric measurements, socioeconomic factors and personal habits. The multiple variable analysis showed that age (OR, 1.99; 95% CI, 1.03 - 3.86; P=0.04) and increased salt intake (OR, 2.21; 95% CI, 1.12 - 4.35; P=0.02) were associated with H. pylori infection.

CONCLUSIONS

More than half of the study subjects were infected with H. pylori in Kazakhstan. The prevalence of H. pylori infection was independently associated with older age and regular high salt consumption.

Novel treatment for gastric intestinal metaplasia, a precursor to cancer

BACKGROUND AND AIM

Gastric intestinal metaplasia (GIM) is precancerous with a worldwide prevalence of 25%. Eradicating Helicobacter pylori prevented about half of gastric cancers; failure to prevent the rest was attributed to GIM. GIM is irreversible and often extensive. There is no treatment. Existing endoscopic mucosal resection (EMR) is designed to treat early gastric cancer of usually <2 cm. We designed a two-endoscope technique of EMR for extensive lesions such as GIM.

METHODS

Forty patients with histologically confirmed moderate to severe GIM (operative link on GIM [OLGIM] classification) received the treatment in a daycare center. Chromoendoscopy with methylene blue was first performed to indicate the GIM. Submucosal saline injections were used to lift the stained mucosa to form multiple safety cushions, which were transformed into artificial polyps by suction and ligation, using a cap familiar to gastroenterologists for ligation of esophageal varices. EMRs were then achieved by snare polypectomy. By rotating two gastroscopes, one was designated to perform lift and snare and the other to perform suction and ligation; cycles of lift-ligate-snare were performed until all stained mucosa was removed. Assessment chromoendoscopy with ≥seven biopsies was performed at 6 months.

RESULTS

A total of 227 EMRs were performed, with a median of 3.5 per patient. Bleeding was uncommon and minimal. Gastric perforation ascribable to loss of a safety cushion occurred in one patient. Chromoendoscopy at 6 months in 36 willing patients showed no recurrence of GIM.

CONCLUSION

The two-endoscope technique of EMR for GIM was essentially safe and effective, with no recurrence at 6 months. It could be performed by endoscopists with standard skills.

Helicobacter pylori antibody and pepsinogen testing for predicting gastric microbiome abundance

Background

Although the high-throughput sequencing technique is useful for evaluating gastric microbiome, it is difficult to use clinically. We aimed to develop a predictive model for gastric microbiome based on serologic testing.

Methods

This study was designed to analyze sequencing data obtained from the Hanyang University Gastric Microbiome Cohort, which was established initially to investigate gastric microbial composition according to the intragastric environment. We evaluated the relationship between the relative abundance of potential gastric cancer-associated bacteria (nitrosating/nitrate-reducing bacteria or type IV secretion system [T4SS] protein gene-contributing bacteria) and serologic markers (IgG anti-Helicobacter pylori [HP] antibody or pepsinogen [PG] levels).

Results

We included 57 and 26 participants without and with HP infection, respectively. The relative abundance of nitrosating/nitrate-reducing bacteria was 4.9% and 3.6% in the HP-negative and HP-positive groups, respectively, while that of T4SS protein gene-contributing bacteria was 20.5% and 6.5% in the HP-negative and HP-positive groups, respectively. The relative abundance of both nitrosating/nitrate-reducing bacteria and T4SS protein gene-contributing bacteria increased exponentially as PG levels decreased. Advanced age (only for nitrosating/nitrate-reducing bacteria), a negative result of IgG anti-HP antibody, low PG levels, and high Charlson comorbidity index were associated with a high relative abundance of nitrosating/nitrate-reducing bacteria and T4SS protein gene-contributing bacteria. The adjusted coefficient of determination (R²) was 53.7% and 70.0% in the model for nitrosating/nitrate-reducing bacteria and T4SS protein gene-contributing bacteria, respectively.

Conclusion

Not only the negative results of IgG anti-HP antibody but also low PG levels were associated with a high abundance of nitrosating/nitrate-reducing bacteria and T4SS protein gene-contributing bacteria.

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

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

Evaluation of gastric microbiome and metagenomic function in patients with intestinal metaplasia using 16S rRNA gene sequencing

BACKGROUND

Despite recent advances in studies on the gastric microbiome, the role of the non-Helicobacter pylori gastric microbiome in gastric carcinogenesis remains unclear. We evaluated the characteristics of the gastric microbiome and metagenomic functions in patients with IM.

METHODS

Participants were classified into six groups according to disease status (chronic superficial gastritis [CSG], intestinal metaplasia [IM], and cancer) and H. pylori- infection status (H. pylori-positive and H. pylori-negative). The gastric microbiome was analyzed in mucosal tissues at the gastric antrum by 16S rRNA gene sequencing. Moreover, we assessed the metagenome including the type IV secretion system (T4SS) gene, as T4SS proteins are essential for transferring CagA from H. pylori- into the human gastric epithelium.

RESULTS

Among the 138 included patients, 48, 9, 23, 14, 12, and 32 were classified into the H. pylori-negative CSG, H. pylori-negative IM, H. pylori-negative cancer, H. pylori-positive CSG, H. pylori-positive IM, and H. pylori-positive cancer groups, respectively. Cyanobacteria were predominant in the H. pylori-negative CSG group compared to in the H. pylori-negative IM and H. pylori-negative cancer groups (H. pylori-negative CSG vs H. pylori-negative IM vs H. pylori-negative cancer: 14.0% vs 4.2% vs 0.04%, P < 0.001). In contrast, Rhizobiales were commonly observed in the H. pylori-negative IM group (H. pylori-negative CSG vs H. pylori-negative IM vs H. pylori-negative cancer: 1.9% vs 15.4% vs 2.8%, P < 0.001). The relative abundance of Rhizobiales increased as H. pylori-infected stomachs progressed from gastritis to IM. In the H. pylori-negative IM group, genes encoding T4SS were prevalent among the metagenome. Additionally, after H. pylori- eradication therapy, the gastric microbiome was similar to the microbiome observed after spontaneous clearance of H. pylori-.

CONCLUSIONS

The relative abundance of Rhizobiales was higher in patients with H. pylori-negative IM than in those with H. pylori-negative CSG or cancer. Additionally, T4SS genes were highly observed in the metagenome of patients with IM. Highly abundant T4SS proteins in these patients may promote gastric carcinogenesis.

Exploring current status of Helicobacter pylori infection in different age groups of patients with dyspepsia

Recent data from Asian countries including India has shown a significant decline in the frequency of peptic ulcer disease (PUD) compared to the past. H. pylori is considered the most important risk factor for PUD, and we aimed to explore the current frequency of H. pylori infection in different age groups of patients with dyspepsia. Patients >15 years of age with dyspeptic symptoms were prospectively recruited in this study from 2010 to 2014 after obtaining informed consent. Patients were divided into three age groups: 15-30 years, 31-50 years, and >50 years, and the minimum sample size required in the three groups with a power of 90% was 259, 256, and 188, respectively. All patients underwent upper gastrointestinal endoscopy; rapid urease test was done on gastric mucosal biopsy to detect H. pylori. The clinical, demographic features and socioeconomic status were recorded. The institute review board approved the study. We included 1000 patients with dyspepsia during the study period. Their mean age was 40.0+13.3 years, and 69.3% were males. Infection with H. pylori was detected in 419 (41.9%) patients. Among men, H. pylori was present in 45.7% while the frequency of infection in women was lower at 33.2% (p < 0.001). In the 15-30 years age group (n = 303), the frequency of infection was 42.6% while it was 48.3% in the 31-50 years group (n = 350) and 34.9% in the above 50 years group (n = 347). Male sex was a significant risk factor for H. pylori infection (p < 0.001). H. pylori infection, an important risk factor for PUD, was detected in less than half of the dyspeptic patients in the current study.

The prevalence of Helicobacter pylori is decreasing in Iranian patients

AIM

The objective of this study was to evaluate the time trend of Helicobacter pylori (H. pylori) prevalence and presence of intestinal Metaplasia over the period of seven years among gastritis Iranian patients.

BACKGROUND

H. pylori is the major causal factor in chronic gastritis. Its acquisition leads to a chronic, usually lifelong, inflammation of the gastric mucosa, which may gradually progress to atrophy with intestinal metaplasia in a significant proportion of infected individuals.

PATIENTS AND METHODS

H. pylori and intestinal Metaplasia data among 14,860 consecutive gastritis patients, who referred to the gastrointestinal department of Tehran's Taleghani Hospital in Iran from 2008 to 2014, was examined by sex and age group. The patients were divided into six age groups (16-30, 30-40, 40-50, 50-60 and >70). The chi-square test was used to compare the qualitative variables.

RESULTS

The overall prevalence rate among patient with H. pylori infection was 83.5% (12406/14860) and 11,394 (84.1%) of them were related to the gastritis. The prevalence rate of H. pylori among patient with severe gastritis was significantly higher (P<0.05) compared to mild and moderate gastritis. In addition, the prevalence of H. pylori decreased with age and has been declined in recent years. The presence of intestinal metaplasia increased with age (P<0.05).

CONCLUSION

The results of this study showed that the prevalence of H. pylori infection in Iranian population has been declined in recent years; nevertheless it seems to be highly prevalent in Iran. We also find a significant positive relationship between H. pylori infection and gastritis. There is no association between sex and infection, however in contrast with the most studies its prevalence decreased with age.