Pylori Infection Research Articles

Factors associated with precancerous stomach lesions and progresion: A 7-year multi-center prospective cohort study on the low incidence of gastric cancer in central Saudi Arabia.

In Saudi Arabia (SA) no data are available on precancerous stomach lesions (PSLs) or the associated risk factors. We aimed to identify PSLs and investigate factors associated with PSLs and their progression. This 7-year prospective study screened for PSLs in asymptomatic Saudi patients aged 45-75 years in central SA (n = 35,640). Those who had high-sensitivity guaiac fecal occult blood tests (HSgFOBT+) and negative colonoscopy results (n = 1242) were subjected to upper GI endoscopy to identify PSLs and were followed up every 3 years or earlier, depending on the type of PSL. Factors associated with PSLs were investigated. The 7-year participation rate was 86.9% (1080/1242). The 7-year prevalence of PSLs was 30.9% (334/1080). The incidence rate of PSLs was 134 new cases/100,000 population/year, total population at risk - 35,640 and 44.3 new cases/1,000 persons/year among the 1080 participants with HSgFOBT+ and negative colonoscopy results. Among the 334 participants with PSLs, 8 (2.4%) had neoplastic progression to GC during the surveillance period. Age, Helicobacter pylori infection, smoking status, a diet with preserved salty foods, low income, and a family history of GC were associated with PSLs. The incidence of GC is low in central SA, but screening for PSLs among participants with HSgFOBT+ and negative colonoscopy findings may contribute to the early detection and subsequent treatment of GC. HP eradication, not smoking, normal body weight, and adhering to a healthy diet seem to be potential factors associated with the development of PSLs. Further studies are needed to search if such interventions would decrease the incidence of PSLs and progression to early GC.

Simplified Helicobacter pylori therapy for patients with penicillin allergy: a randomised controlled trial of vonoprazan-tetracycline dual therapy

Background and aimsThis study aimed to evaluate the efficacy and safety of vonoprazan and tetracycline (VT) dual therapy as first-line treatment for Helicobacter pylori infection in patients with penicillin allergy.MethodsIn...

Association between Helicobacter pylori antibodies and otolaryngological diseases

ObjectiveObservational studies have shown that Helicobacter pylori is related to some otolaryngological diseases. However, it is unclear if H. pylori infection causally affects these diseases. To elucidate H. pylori role in 12 common otolaryngological diseases, we conducted two-sample Mendelian randomization analysis. MethodsSingle-nucleotide polymorphisms associated with 7 H. pylori antibodies (IgG, CagA, Catalase, GroEL, OMP, UREA and Vac A) served as instrumental variables. We primarily employed random-effects inverse variance weighting for causal estimation, supplemented by MR Egger, weighted median, simple mode, and weighted mode. Sensitivity analyses, including heterogeneity, pleiotropy, and leave-one-out tests, validated robustness. ResultsMR analysis using inverse variance weighting (random effects) revealed genetically predicted H. pylori CagA antibodies correlated with increased risk of nonsuppurative otitis media (OR = 1.0778, 95% CI 1.0114–1.1487, p-value = 0.021). No causal relationship was observed between H. pylori antibodies and other common otolaryngological diseases. Sensitivity analyses found no pleiotropy or heterogeneity, affirming result reliability. ConclusionThis study suggests that the levels of H. pylori CagA antibodies may contribute to the development of nonsuppurative otitis media. Further studies are needed in the future to elucidate the specific mechanism of H. pylori in this disease. Level of evidenceLevel III.

Impact of Helicobacter pylori Eradication on Inflammatory Bowel Disease Onset and Disease Activity: To Eradicate or Not to Eradicate?

Helicobacter pylori infection has significant epidemiological relevance due to the carcinogenic nature of this bacterium, which is potentially associated with cancer. When detected, it should ideally be eradicated using a treatment that currently involves a combination of gastric acid suppressors and multiple antibiotics. However, this treatment raises questions regarding efficacy and safety profiles in patients with specific comorbidities, including inflammatory bowel diseases (IBD). Eradication therapy for H. pylori includes components associated with adverse gastrointestinal events, such as Clostridioides difficile colitis. This necessitates quantifying this risk through dedicated studies to determine whether this antimicrobial treatment could be significantly associated with IBD relapse or exacerbation of pre-existing IBD, as well as whether it could potentially lead to the de novo onset of IBD. Although the available evidence is reassuring about the safety of eradication therapy in patients with IBD, it is limited, and there are no specific recommendations for this particular situation in the leading international IBD and H. pylori guidelines. Therefore, studies need to evaluate the efficacy and safety profiles of the available antimicrobial regimens for H. pylori eradication in patients with IBD, both in clinical trial settings and in real-life studies.

Prevalence of Helicobacter pylori infection among patients with esophageal carcinoma.

Helicobacter pylori (H. pylori) is a widespread microorganism related to gastric adenocarcinoma (AC). In contrast, it has been reported that an inverse association exists between H. pylori infection and esophageal carcinoma. The mechanisms underlying this supposedly protective effect remain controversial. To determine the prevalence of H. pylori infection in esophageal carcinoma patients, we performed a retrospective observational study of esophageal tumors diagnosed in our hospital. We retrospectively reviewed the prevalence of H. pylori infection in a cohort of patients diagnosed with esophageal carcinoma. Concomitant or previous proton pump inhibitor (PPI) usage was also recorded. A total of 89 patients with esophageal carcinoma (69 males, 77.5%), with a mean age of 66 years (range, 26-93 years) were included. AC was the most frequent pathological variant (n = 47, 52.8%), followed by squamous cell carcinoma (n = 37, 41.6%). Fourteen ACs (29.8%) originated in the gastroesophageal junction and 33 (70.2%) in the esophageal body. Overall, 54 patients (60.7%) presented at stages III and IV. Previous H. pylori infection occurred only in 4 patients (4.5%), 3 with AC (6.3% of all ACs) and 1 with squamous cell carcinoma (2.7% of all squamous cell tumors). All patients with previous H. pylori infection had stage III-IV. Only one patient had received prior H. pylori eradication therapy, whereas 86 (96.6%) had received previous or concomitant PPI treatment. In our cohort of patients, and after histologic evaluation of paraffin-embedded primary tumors, we found a very low prevalence of previous H. pylori infection. We also reviewed the medical history of the patients, concluding that the majority had received or were on PPI treatment. The minimal prevalence of H. pylori infection found in this cohort of patients with esophageal carcinoma suggests a protective role.

Chronic cigarette smoke exposure masks pathological features of Helicobacter pylori infection while promoting tumor initiation.

Gastric cancer is the fifth most common cancer and the fifth leading cause of cancer deaths worldwide. Chronic infection by the bacterium Helicobacter pylori is the most prominent gastric cancer risk factor, but only 1-3% of infected individuals will develop gastric cancer. Cigarette smoking is another independent gastric cancer risk factor, and H. pylori- infected smokers are at a 2-11-fold increased risk of gastric cancer development, but the direct impacts of cigarette smoke on H. pylori pathogenesis remain unknown. In this study, male C57BL/6 mice were infected with H. pylori and began smoking within one week of infection. The mice were exposed to cigarette smoke (CS) five days/week for 8 weeks. CS exposure had no notable impact on gross gastric morphology or inflammatory status compared to filtered-air (FA) exposed controls in mock-infected mice. However, CS exposure significantly blunted H. pylori- induced gastric inflammatory responses, reducing gastric atrophy and pyloric metaplasia development. Despite blunting these classic pathological features of H. pylori infection, CS exposures increased DNA damage within the gastric epithelial cells and accelerated H. pylori- induced dysplasia onset in the INS-GAS gastric cancer model. These data suggest that cigarette smoking may clinically silence classic clinical symptoms of H. pylori infection but enhance the accumulation of mutations and accelerate gastric cancer initiation.

The protective effects of Helicobacter pylori: A comprehensive review

Previous reports have estimated that approximately half of the world’s population is infected with Helicobacter pylori, the most prevalent infectious agent responsible for gastrointestinal illnesses. Due to the life-threatening effects of H. pylori infections, numerous studies have focused on developing medical therapies for H. pylori infections, while the commensal relationship and positive impacts of this bacterium on overall human health have been largely overlooked. The inhibitory efficacy of H. pylori on the progression of several chronic inflammatory disorders and gastrointestinal diseases has recently raised concerns about whether this bacterium should be eradicated in affected individuals or maintained in an appropriate balance depending on the patient’s condition. This review investigates the beneficial effects of H. pylori in preventing various diseases and discusses the potential association of conditions such as inflammatory disorders with the absence of H. pylori.

Evaluation of the Rock1 and microRNA-148a expression in biopsies collected from patients with Helicobacter pylori induced gastritis

BackgroundHelicobacter pylori infection is one of the most common chronic bacterial infections, especially in developing countries. MicroRNA-148a is involved in the regulation of various genes, including Rock1, which is altered in gastric cancer. Decreased expression of mir-148a leads to tumor metastasis and increased Rock1 gene expression in gastric cancer. This study aimed to investigate the expression of these genes in biopsies collected from patients with H. pylori induced gastritis.MethodsInformed consent forms were gotten from the studied patients with gastritis who needed endoscopy. Gastric biopsies were taken by a gastroenterologist from patients with inflammation. Rapid urease test, stool antigen detection, and histopathological staining were used to determine the H. pylori infected patients. Real time PCR was used to evaluate the miRNA and Rock1 expression levels.ResultsThe Rock1 expression level in biopsies that were positive for H. pylori was significantly increased compared to our control gastritis group that were H. pylori-negative, but the results were not statistically significant. Moreover, the mir-148a expression level in H. pylori-positive patients with gastritis was increased compared to our control group. However, the results were not statistically significant. We did not find a significant relation between the expression levels of Rock1 and mir-148a in samples with gastritis infected or uninfected by H. pylori. This result may be due to the small sample size.ConclusionWe suggest that this test should be carried out with more samples, and the comparison should be done between biopsies with inflammation and no inflammation in a patient.

The Impact of TBXA2R Gene Variants on the Risk of Aspirin-Induced Upper Gastrointestinal Bleeding: A Case-Control Study.

Objective: Upper gastrointestinal bleeding (UGIB) has been identified as a potential adverse drug reaction associated with the use of low-dose aspirin (LDA). This study aimed to investigate the relationship between variants in the TBXA2R gene, which is involved in platelet aggregation, and the risk of UGIB in patients with cardiovascular diseases treated with LDA. Methods: A case-control study was conducted at a Brazilian hospital complex. Three groups were defined: (1) case group (n = 50): patients with cardiovascular disease who used LDA and were diagnosed with UGIB of non-variceal etiology, (2) LDA control group (n = 50): patients with cardiovascular disease who used LDA without developing UGIB, and (3) healthy control group (n = 189). Data were collected through face-to-face interviews, and blood samples were collected for the analysis of Helicobacter pylori infection and genotyping of 3 genetic variants [rs2238631 (C > T), rs4807491 (A > G), and rs1131882 (A > G)]. Results: The case group had a significantly higher frequency of carriers of the rs4807491.G allele compared to the control group of LDA users (P-value = .004). No significant difference was observed in the proportion of carriers of the rs2238631.T and 1131882.G variants between the studied groups. Carriers of rs2238631.T (OR: 4.515, 95% CI: 1.37-14.89) and rs4807491.G allele (OR: 3.232, 95% CI: 1.12-9.37) exhibited a higher risk of UGIB. Conclusion: These findings suggest that the presence of the rs2238631 and rs4807491 variant alleles is associates with a 3- to 4-fold increased risk of UGIB in patients with cardiovascular diseases treated with LDA. Future studies with larger sample sizes should confirm these results and to better identify individuals who may benefit from chronic LDA use.

Helicobacter pylori upregulates PAD4 expression via stabilising HIF-1α to exacerbate rheumatoid arthritis

ObjectiveHelicobacter pylori infection has been reported to aggravate rheumatoid arthritis (RA), but the relevant mechanism remains unclear. This study aimed to investigate the underlying pathogenic mechanism of H. pylori infection...

Causal associations between Helicobacter Pylori infection and the risk and symptoms of Parkinson's disease: a Mendelian randomization study.

Increasing evidence suggests an association between Helicobacter pylori (HP) infection and Parkinson's disease (PD) and its clinical manifestations, but the causal relationship remain largely unknown. To investigate the causal relationship between HP infection and PD risk, PD symptoms, and secondary parkinsonism, we conducted two-sample Mendelian randomization (MR). We obtained summary data from genome-wide association studies for seven different antibodies specific to HP proteins and five PD-related phenotypes. The inverse-variance weighted (IVW), weighted median, weighted mode, and MR-Egger methods were used to assess the causal relationships. Sensitivity analyses were performed to examine the stability of the MR results and reverse MR analysis was conducted to evaluate the presence of reverse causality. Genetically predicted HP antibodies were not causally associated with an increased risk of PD. However, HP cytotoxin-associated gene-A (CagA) and outer membrane protein (OMP) antibody level were causally associated with PD motor subtype (tremor to postural instability/gait difficulty score ratio; β = -0.16 and 0.46, P = 0.002 and 0.048, respectively). HP vacuolating cytotoxin-A (VacA) antibody level was causally associated with an increased risk of PD dementia [odds ratio (OR) = 1.93, P = 0.040]. Additionally, HP OMP antibody level was identified as a risk factor for drug-induced secondary parkinsonism (OR = 2.08, P = 0.033). These results were stable, showed no evidence of heterogeneity or directional pleiotropy, and no evidence of a reverse causal relationship. Our findings indicate that HP infection does not increase the risk of PD, but contributes to PD motor and cognitive symptoms. Different types of HP antibodies affect different symptoms of PD. Eradication of HP infection may help modulate and improve symptoms in PD patients.

Bidirectional relationship between Helicobacter pylori infection and nonalcoholic fatty liver disease: insights from a comprehensive meta-analysis.

Helicobacter pylori (H. pylori) infection and nonalcoholic fatty liver disease (NAFLD) represent significant concerns in global health. However, the precise relationship between H. pylori and NAFLD remains a subject of ongoing debate. This study endeavors to elucidate the association between H. pylori infection and the susceptibility to NAFLD. Furthermore, we aim to investigate the interplay among H. pylori infection, NAFLD, and metabolic syndrome (MetS). We conducted an extensive search of the PubMed, EMBASE, and Web of Science databases spanning from inception to January 2024. Our examination focused on rigorous studies investigating the correlation between H. pylori infection and NAFLD. Utilizing a random-effects model, we computed the pooled odds ratio (OR) and corresponding 95% confidence interval (CI). Additionally, we assessed statistical heterogeneity, performed sensitivity analyses, and scrutinized the potential for publication bias. Thirty-four studies involving 175,575 individuals were included in our meta-analysis. Among these, 14 studies (involving 94,950 patients) demonstrated a higher incidence of NAFLD in H. pylori infection-positive individuals compared to H. pylori infection-negative individuals [RR = 1.17, 95% CI (1.10, 1.24), Z = 4.897, P < 0.001]. Seventeen studies (involving 74,928 patients) indicated a higher positive rate of H. pylori infection in patients with NAFLD compared to those without NAFLD [RR = 1.13, 95% CI (1.02, 1.24), Z = 2.395, P = 0.017]. Sensitivity analyses confirmed the robustness of these findings, and funnel plot analysis revealed no significant publication bias. Furthermore, we observed associations between H. pylori infection or NAFLD and various metabolic factors, including body mass index (BMI), blood pressure, lipids, liver function, and kidney function. Our meta-analysis presents evidence supporting a reciprocal relationship between H. pylori infection and the susceptibility to NAFLD. Nevertheless, additional investigations are warranted to bolster this correlation and unravel the underlying mechanisms involved.

Causal association between Helicobacter pylori infection and Sjogren’s syndrome: a bidirectional Mendelian randomization analysis

BackgroundThe results of observational studies indicate a potential link between Helicobacter pylori infection and Sjogren’s syndrome (SS), but the causal relationship between them remains unknown. This study applied Mendelian randomization (MR) to evaluate this relationship.MethodGenome-wide association study (GWAS) summary statistics on H. pylori infection [sample size=8735 (EBI, https://gwas.mrcieu.ac.uk/)] and SS [sample size=368,028 (cases=2495, controls=365533) (FinnGen, https://r9.finngen.fi/)] were analyzed. We used bidirectional MR to evaluate the association between H. pylori infection and SS and identify causation. The major MR analysis method was inverse-variance weighted (IVW) MR, supplemented by MR‒Egger and weighted median approaches. In addition, the stability and reliability of the results were tested using the retention method, heterogeneity test, and horizontal gene pleiotropy test.ResultsEvidence of the impact of H. pylori infection on SS risk was found in the IVW results [odds ratio (OR)=1.6705; 95% confidence interval (CI)=1.0966 to 2.5446; P=0.0168]. Evidence of the impact of SS on H. pylori infection risk was also found (OR=1.0158; 95% CI=1.0033 to 1.0285; P=0.0128).ConclusionThe results of MR analysis support a causal association between H. pylori infection and SS and indicate that SS can lead to a greater risk of H. pylori infection. Our research will support the development of novel approaches for continued H. pylori and SS-related research and therapy that consider the genetic relationship between H. pylori infection and SS.

Exploring the Underlying Mechanisms of Preventive Treatment Related to Dietary Factors for Gastric Diseases.

Gastric diseases have emerged as one of the main chronic diseases in humans, leading to considerable health, social, and economic burdens. As a result, using food or "food and medicinal homologous substances" has become an effective strategy to prevent gastric diseases. Diet may play a crucial role in the prevention and mitigation of gastric diseases, particularly long-term and regular intake of specific dietary components that have a protective effect on the stomach. These key components, extracted from food, include polysaccharides, alkaloids, terpenoids, polyphenols, peptides, probiotics, etc. The related mechanisms involve regulating gastric acid secretion, protecting gastric mucosa, increasing the release of gastric defense factors, decreasing the level of inflammatory factors, inhibiting Helicobacter pylori infection, producing antioxidant effects or reducing oxidative damage, preventing gastric oxidative stress by inhibiting lipid peroxides, activating Nrf2 signaling pathway, and inhibiting NF-κB, TLR4, and NOS/NO signaling pathways.

Use of bidirectional Mendelian randomization to unveil the association of Helicobacter pylori infection and autoimmune thyroid diseases.

Previous observational studies found associations between Helicobacter pylori infection and autoimmune thyroid diseases (AITDs), but the causal nature of this association is still uncertain. We investigated the causal effect of six crucial antibodies against H. pylori on AITDs using a bidirectional Mendelian randomization (MR). We found that anti-H. pylori outer membrane protein (OMP) significantly increased the risk of hyperthyroidism and Graves' disease (GD). In addition, our reverse MR analysis indicated that hyperthyroidism could increase the levels of cytotoxin-associated gene A and OMP antibodies. We also observed causal roles of GD on anti-H. pylori OMP. Our analyses indicate the mutual effects of H. pylori infection and AITDs, suggesting the existence of a gut-thyroid axis. These results also provide evidence of the bidirectional causal association between anti-H. pylori OMP with hyperthyroidism and GD, resulting in a vicious circle.

Targeting gut-microbiota for gastric cancer treatment: a systematic review.

Preclinical research has identified the mechanisms via which bacteria influence cancer treatment outcomes. Clinical studies have demonstrated the potential to modify the microbiome in cancer treatment. Herein, we systematically analyze how gut microorganisms interact with chemotherapy and immune checkpoint inhibitors, specifically focusing on how gut bacteria affect the pharmacokinetics and pharmacodynamics of cancer treatment. This study searched Web of Science, Scopus, and PubMed until August 2023. Studies were screened by their title and abstract using the Rayyan intelligent tool for systematic reviews. Quality assessment of studies was done using the JBI critical appraisal tool. Alterations in the gut microbiome are associated with gastric cancer and precancerous lesions. These alterations include reduced microbial alpha diversity, increased bacterial overgrowth, and decreased richness and evenness of gastric bacteria. Helicobacter pylori infection is associated with reduced richness and evenness of gastric bacteria, while eradication only partially restores microbial diversity. The gut microbiome also affects the response to cancer treatments, with higher abundances of Lactobacillus associated with better response to anti-PD-1/PD-L1 immunotherapy and more prolonged progression-free survival. Antibiotic-induced gut microbiota dysbiosis can reduce the anti-tumor efficacy of 5-Fluorouracil treatment, while probiotics did not significantly enhance it. A probiotic combination containing Bifidobacterium infantis, Lactobacillus acidophilus, Enterococcus faecalis, and Bacillus cereus can reduce inflammation, enhance immunity, and restore a healthier gut microbial balance in gastric cancer patients after partial gastrectomy. Probiotics and targeted interventions to modulate the gut microbiome have shown promising results in cancer prevention and treatment efficacy.Systematic review registration: https://osf.io/6vcjp.

Association of triglyceride-glucose index with helicobacter pylori infection and mortality among the US population

BackgroundLimited research has explored the potential association between the Triglyceride-Glucose (TyG) and mortality, especially in individuals with Helicobacter pylori (H. pylori) infection. This study seeks to investigate the correlation between the TyG index and H. pylori infection and investigate whether the associations between the TyG index exposure and all-cause mortality are mediated by H. pylori infection.MethodsThe study utilized data from the National Health and Nutrition Examination Survey (NHANES) 1999–2018, incorporating a final sample size of 2,187 participants. Both univariable and multivariable-adjusted logistic regression analyses were employed to examine the relationship between H. pylori infection and relevant covariates. To assess the association between TyG index, and all-cause mortality in individuals with or without H. pylori infection, Cox regression analysis, and restricted regression cubic spline analysis were implemented.ResultsA significant positive correlation was observed between the TyG index and an elevated risk of H. pylori infection [OR 1.157, 95% CI (1.383 ~ 1.664)]. This correlation persisted even after adjusting for confounding factors [OR 1.189, 95% CI (1.003, 1.411), P < 0.05]. Furthermore, in patients with positive H. pylori infection, a noteworthy nonlinear correlation between the TyG index and all-cause mortality was identified (P = 0.0361). With an increase in the TyG index, all-cause mortality exhibited a corresponding rise, particularly following adjustment for all potential confounding factors. Conversely, in patients with negative H. pylori infection, no significant association was observed between the TyG index and all-cause mortality after adjusting for potential confounding factors.ConclusionA higher TyG index was linked to increased H. pylori infection risks. Participants in the higher quantile group of the TyG index are positively associated with higher all-cause mortality compared to the higher quantile group of the TyG index in H. pylori-positive participants instead of H. pylori-negative participants.

Causal relationships of infection with Helicobacter pylori and herpesvirus on periodontitis: A Mendelian randomization study

BackgroundTo explore the causal association between Helicobacter pylori (H. pylori) infection, herpesvirus infection and periodontitis (PD) from a genetic perspective using Mendelian randomization (MR). MethodsThe PD data were derived from genome-wide association study (GWAS) from the Dental Endpoints (GLIDE) consortium, and the FinnGen Biobank provided data on H. pylori and herpesvirus infections. In addition, we examined GWAS data for subtypes of H. pylori and herpesvirus infection. Inverse variance weighting (IVW) was selected as a major analysis technique, and weighted median (WM), weighted model, simple model, and MR-Egger regression were added as supplementary methods. To verify the findings, the effects of pleiotropy and heterogeneity were assessed. ResultsGenetically predicted H. pylori infection (OR = 0.914, 95%CI = 0.693–1.205, P = 0.523), anti-H. pylori VacA (OR = 0.973, 95%CI = 0.895–1.057, P = 0.515), anti-H. pylori CagA (OR = 1.072, 95%CI = 0.986–1.164; P = 0.102), Epstein-Barr virus (EBV) infection (OR = 1.026, 95%CI = 0.940–1.120, P = 0.567), Herpes simplex virus (HSV) infection (OR = 0.962, 95%CI = 0.883–1.048, P = 0.372), cytomegalovirus (CMV) infection (OR = 1.025, 95%CI = 0.967–1.088, P = 0.415), EBV nuclear antigen-1 (EBNA1) (OR = 1.061, 95%CI = 0.930–1.209, P = 0.378), EBV virus capsid antigen (VCA) (OR = 1.043, 95CI% = 0.890–1.222, P = 0.603), HSV-1 (OR = 1.251, 95%CI = 0.782–2.001, P = 0.351), HSV-2 (OR = 1.020, 95%CI = 0.950–1.096, P = 0.585), CMV IgG (OR = 0.990, 95CI% = 0.882–1.111, P = 0.861) were not associated with PD, indicated that H. pylori and herpesvirus infection had no causal relationship to PD. Reverse studies also found no cause effect of PD on H. pylori or herpesvirus infection. The results of the sensitivity analysis suggested the robustness of the MR results. ConclusionThis study offered preliminary proof that H. pylori and herpesvirus infections were not causally linked to PD, and vice versa. However, more robust instrumental variables (IVs) and larger samples of GWAS data were necessary for further MR analysis.

High galectin expression in Helicobacter pylori-infected gastric mucosa in childhood

BackgroundMild Th1 and Th17 immune responses in childhood against Helicobacter pylori are presumed to be responsible for H. pylori colonization and mucosal atrophy reduction. However, the mechanism remains unclear. In this study, we aimed to investigate the childhood-specific immune responses observed after H. pylori infection by analyzing galectin expression in the gastric mucosa. We focused on galectin-1 (Gal-1) and galectin-9 (Gal-9), which function to suppress Th1 and Th17 immune responses. MethodsWe analyzed changes in the expression of Gal-1 and Gal-9 in the gastric mucosa of pediatric patients with H. pylori infection. Ten pediatric patients with and ten patients without H. pylori infection who underwent biopsy to assess the cause of chronic abdominal symptoms using esophagogastroduodenoscopy were evaluated. Gal-1 and Gal-9 expression in the biopsy tissues of the gastric antrum and corpus was analyzed by immunohistochemical staining. ResultsGal-1 expression was significantly increased in the stromal cells of the corpus owing to H. pylori infection. No alterations in Gal-1 expression due to H. pylori infection were observed in the antral tissue. Helicobacter pylori infection considerably increased Gal-9 expression in all tissues. According to previous reports, the increased expression of Gal-9 associated with H. pylori infection is not observed in adults. Therefore, the increased expression of Gal-9 associated with H. pylori infection is specific to pediatric patients. ConclusionThe increased expression of Gal-1 and Gal-9 may suppress Th1 and Th17 immune responses against H. pylori infection during childhood, promote H. pylori colonization, and reduce inflammation in the gastric mucosa of pediatric patients.

Risk factors for Helicobacter pylori infection in children with gastrointestinal symptoms in Vietnam

ObjectivesTo investigate the prevalence and risk factors associated with Helicobacter pylori infection in Vietnamese children. MethodsChildren under 16 years old with gastrointestinal symptoms underwent esophagogastroduodenoscopy and H. pylori infection was diagnosed using rapid urease test. ResultsA total of 246 children with gastrointestinal symptoms were included. The mean age was 8.4 ± 2.6 years. A total 81.3% tested positive for H. pylori. Children infected with H. pylori had a lower rate of nausea but a higher rate of lesions in the duodenal bulb and nodular lesions than children without H. pylori infection (26.5% vs 45.6%, P <0.01; 40.0% vs 23.9%; P = 0.04; and 68.5% vs 30.3%, P <0.0001, respectively). Compared with children aged under 5 years, children aged 11 years and older were four times more likely to be infected with H. pylori, with odds ratio (OR) 3.50, 95% confidence interval (CI) 1.07-11.39, P = 0.04. Washing hands with soap was associated with a reduced risk of H. pylori infection by three times (OR 0.35, 95% CI 0.17-0.69, P = 0.002). Children living in a family where members had a history of H. pylori infection were nine times more likely to be infected with H. pylori (OR 8.87, 95% CI 1.15-68.45, P = 0.04). ConclusionsThe prevalence of H. pylori infection in Vietnamese children with gastroenteritis is high. Our results identified several risk factors and emphasize the role of handwashing with soap before eating and after using the toilet in reducing the risk of H. pylori infection in children.