Ethnic difference of Helicobacter pylori gastritis: Korean and Japanese gastritis is characterized by male- and antrum-predominant acute foveolitis in comparison with American gastritis

Prevalence of Gastric Precursor Lesions in Countries With Differential Gastric Cancer Burden: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

The prevalence of precursor lesions for gastric cancer (GC) and the differential burden between countries of varying GC risk is not well-understood. We conducted a systematic review and meta-analysis to estimate the global prevalence of precursor lesions.

METHODS

We estimated the prevalence of atrophic gastritis (AG), gastric intestinal metaplasia (IM), and dysplasia in regions with low, medium, and high GC incidence. Because IM is an advanced manifestation of AG, we assessed the prevalence of less advanced precursors, regardless of the presence of more advanced lesions. Prevalence was sub-stratified by Helicobacter pylori infection, symptomatology, and period (<2000, 2000-2010, and >2010).

RESULTS

Among the 582 articles that underwent full-text review, 166 studies met inclusion criteria. The global prevalence estimates of AG, IM, and dysplasia were 25.4%, 16.2%, and 2.0%, respectively, on the basis of 126 studies that reported the prevalence of less advanced precursors, regardless of the presence of more advanced lesions. The prevalence of all precursor lesions was higher in high and medium compared with low GC incidence countries (P < .01). Prevalence of AG and IM was significantly higher among H pylori-infected individuals (P < .01) but not statistically different between symptomatic and asymptomatic individuals (P > .17). All precursors demonstrated a secular decrease in prevalence over time.

CONCLUSIONS

Gastric precursor lesions have differences in prevalence in regions with differential GC incidence and are associated with H pylori infection. Because of the substantial prevalence of precursor lesions in both symptomatic and asymptomatic individuals, symptomatic evaluation may not be sufficient to identify individuals at risk. These estimates provide important insights for tailoring GC prevention strategies.

Does enteral nutrition through a percutaneous endoscopic gastrostomy, attenuate Helicobacter pylori colonization?: is it worth mentioning?

OBJECTIVE

In patients who experience difficulties in oral feeding, alimentary intake can be supported by creating direct access into the stomach through a percutaneous endoscopic gastrostomy. The present study purposed to compare naïve and exchanged percutaneous endoscopic gastrostomy tubes in terms of Helicobacter pylori infection and other clinical characteristics.

METHODS

A total of 96 cases who underwent naïve or exchanged percutaneous endoscopic gastrostomy procedures with various indications were incorporated into the study. The patients' demographic data, such as age and gender, etiology of percutaneous endoscopic gastrostomy, anti-HBs status, Helicobacter pylori status, the presence of atrophy and intestinal metaplasia, biochemical parameters, and lipid profiles, had been analyzed. In addition, the anti-HCV and anti-HIV statuses had also been evaluated.

RESULTS

The most common indication for percutaneous endoscopic gastrostomy placement was dementia in 26 (27.08%) cases (p=0.033). The presence of Helicobacter pylori positivity was significantly lower in the exchange group compared to the naïve group (p=0.022). Total protein, albumin, and lymphocyte levels were significantly higher in the exchange group compared to the naïve group (both p=0.001), and the mean calcium, hemoglobin, and hematocrit levels were statistically significantly higher in the exchange group (p<0.001).

CONCLUSION

Preliminary outcomes of the present study revealed that enteral nutrition attenuates the incidence of Helicobacter pylori infection. Considering the acute-phase reactant, the significantly lower ferritin values in the exchange group suggest that there is no active inflammatory process in the patients and that immunity is sufficient.

Correlation between clarithromycin resistance, virulence factors and clinical characteristics of the disease in Helicobacter pylori infected patients in Shahrekord, Southwest Iran

The purpose of this study was to determine the mutations associated with clarithromycin resistance in Helicobacter pylori strains isolated from biopsy samples that were collected from the endoscopic ward of Shahrekord Hajar teaching Hospital and also to study the frequency of virulence factor and their correlation and pathological findings with clarithromycin resistance during the years 2019-2020. In this cross-sectional descriptive study, 152 patients with Helicobacter pylori infection were considered, and then, two common A2142G and A2143G mutations in the 23SrRNA gene associated with resistance were analyzed by Real-time PCR (Taq man). The presence of vacA, iceA1, iceA2, cagA, babA2, and oipA virulence genes was investigated by PCR and electrophoresis in 8% polyacrylamide gel. Then, data were analyzed using the relevant statistical tests. In this study, the frequency of Helicobacter pylori was 76% and the frequency of mutant isolates was 57.2%. The frequencies of A2142G and A2143G point mutations were 42.1% and 28.3%. There was a significant correlation among oipA, vacA, and iceA1 virulence factors, type of disease, chronic inflammatory score, and glandular atrophy with the antibiotic resistance to clarithromycin. There was no significant correlation between the age and sex of the patients with antibiotic resistance. According to the results of this study, it seems that the use of clarithromycin to combat this bacterium should be limited.

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

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

Role of TNF-α-Inducing Protein Secreted by Helicobacter pylori as a Tumor Promoter in Gastric Cancer and Emerging Preventive Strategies

The tumor necrosis factor-α (TNF-α)-inducing protein (tipα) gene family, comprising Helicobacter pylori membrane protein 1 (hp-mp1) and tipα, has been identified as a tumor promoter, contributing to H. pylori carcinogenicity. Tipα is a unique H. pylori protein with no similarity to other pathogenicity factors, CagA, VacA, and urease. American H. pylori strains cause human gastric cancer, whereas African strains cause gastritis. The presence of Tipα in American and Euro-Asian strains suggests its involvement in human gastric cancer development. Tipα secreted from H. pylori stimulates gastric cancer development by inducing TNF-α, an endogenous tumor promoter, through its interaction with nucleolin, a Tipα receptor. This review covers the following topics: tumor-promoting activity of the Tipα family members HP-MP1 and Tipα, the mechanism underlying this activity of Tipα via binding to the cell-surface receptor, nucleolin, the crystal structure of rdel-Tipα and N-terminal truncated rTipα, inhibition of Tipα-associated gastric carcinogenesis by tumor suppressor B-cell translocation gene 2 (BTG2/TIS21), and new strategies to prevent and treat gastric cancer. Thus, Tipα contributes to the carcinogenicity of H. pylori by a mechanism that differs from those of CagA and VacA.

Association of the Helicobacter pylori cagA, vacA, and iceA genotypes with chronic follicular gastritis in a Colombian population at high risk for gastric cancer

INTRODUCTION AND OBJECTIVE

Follicular gastritis is associated with Helicobacter pylori infection, but little is known of its relation to bacterial genotypes. Our aim was to establish the relation between follicular gastritis and different H. pylori strains.

MATERIALS AND METHODS

An analytic case-control study was conducted that included 36 patients with follicular gastritis (cases) and 83 with nonatrophic gastritis (controls). The sociodemographic information was obtained through a questionnaire. Biopsies were evaluated according to the Sydney System and the Wotherspoon scoring system. Helicobacter pylori genotyping was performed using the polymerase chain reaction technique. The quantitative variables were presented as mean and standard deviation and the qualitative variables as proportions and absolute frequency. The effect of each variable on outcome (follicular gastritis) was evaluated through the odds ratio and its 95% confidence interval. Statistical significance was set at a P<0.05.

RESULTS

Follicular gastritis was associated with Helicobacter pylori infection (OR: 13.41, CI: 1.7-103, P=0.01). The CagA+ genotype was present in 56.5% of the cases and 58% of the controls. The cytotoxic VacAs1m1strain was present in 82% of the isolates in both groups. IceA1 frequency was 34.8% in the cases and 26% in the controls and the difference was not statistically significant.

CONCLUSIONS

The population studied had elevated frequencies of cytotoxic Helicobacter pylori strains and the iceA1 genotype was more frequent in follicular gastritis.

Different Pathophysiology of Gastritis in East and West? A Western Perspective

Background

Gastritis results from multifactorial gastric mucosal injury. Helicobacter pylori (Hp) is the main cause, and associated diseases have typical underlying patterns of gastritis. Gastric ulcer and gastric cancer (GC) develop from chronic atrophic corpus gastritis (CAG) which therefore represents the most important pattern. GC incidences in East Asia are substantially higher than elsewhere, and this should be also reflected by higher prevalences of CAG and characteristic differences in pathophysiology compared to the West.

Summary

The few available comparative studies of gastritis in Eastern and Western patients are summarized. The main pathogenic factors of gastritis are discussed together with their limitations to explain local differences in disease outcome. Emphasis was put to also include less well-established pathogenic host and environmental factors of possible impact.

Conclusions

CAG is more prevalent in East Asian areas with high GC incidences than the West. Geographic heterogeneity of associated diseases is due to differences in Hp prevalence and virulence as well as modulating host and environmental factors. The following may contribute to the higher burden of CAG in the East: ABD type of CagA with vacA s1 and babA2 alleles of Hp, host Lewis(b) expression in sej/sej nonsecretors, H. heilmannii, low parietal cell mass, high sodium and nitrate intake, preferences in vegetable and fruit consumption, cigarette smoking, air pollution, alcohol. Conversely, green tea, nonfermented soy products and rice may confer protective effects. Hp is on the decline, but also in a world cleared from this bacterium, differences in host genetics will continue to modify gastric disease outcome together with maintained customs as part of cultural diversity.

Pathobiology of Helicobacter pylori-Induced Gastric Cancer

Colonization of the human stomach by Helicobacter pylori and its role in causing gastric cancer is one of the richest examples of a complex relationship among human cells, microbes, and their environment. It is also a puzzle of enormous medical importance given the incidence and lethality of gastric cancer worldwide. We review recent findings that have changed how we view these relationships and affected the direction of gastric cancer research. For example, recent data have indicated that subtle mismatches between host and microbe genetic traits greatly affect the risk of gastric cancer. The ability of H pylori and its oncoprotein CagA to reprogram epithelial cells and activate properties of stemness show the sophisticated relationship between H pylori and progenitor cells in the gastric mucosa. The observation that cell-associated H pylori can colonize the gastric glands and directly affect precursor and stem cells supports these observations. The ability to mimic these interactions in human gastric organoid cultures as well as animal models will allow investigators to more fully unravel the extent of H pylori control on the renewing gastric epithelium. Finally, our realization that external environmental factors, such as dietary components and essential micronutrients, as well as the gastrointestinal microbiota, can change the balance between H pylori's activity as a commensal or a pathogen has provided direction to studies aimed at defining the full carcinogenic potential of this organism.

Geographic differences in low-dose aspirin-associated gastroduodenal mucosal injury

Aspirin, even at low doses, has been known to cause upper gastro-intestinal complications, such as gastroduodenal ulcers, despite the definite benefits from its antithrombotic effects. Helicobacter pylori (H. pylori) is major pathogen responsible for gastroduodenal ulcer formation. There have been conflicting results about the potential interaction between these two ulcerogenic factors and the geographic areas involved. In Western countries, the prevalence of gastroduodenal ulcers is consistently higher in H. pylori-positive low-dose aspirin (LDA) users than in H. pylori-negative ones, suggesting that H. pylori infection exacerbates LDA-induced gastroduodenal mucosal injury in these geographic areas. Meanwhile, previous studies from Japan have generally reported a similar prevalence of LDA-induced gastroduodenal mucosal injury regardless of the presence of H. pylori infection, indicating that the infection is not an overall exacerbating factor for drug-induced injury. H. pylori infection could have a synergistic or antagonistic interaction with LDA use in adverse gastroduodenal events depending on gastric acid secretion. It is well-recognized that the net effect of H. pylori infection on gastric acid secretion shows considerable geographic variation at the population level. While gastric acid secretion levels were not decreased and were well-preserved in most patients with H. pylori infection from Western countries, the majority of Japanese patients with H. pylori infection exhibited decreased gastric acid secretion. Such large geographic differences in the net effect of H. pylori infection on gastric acid secretion could be at least partly responsible for the geographically distinct interaction between LDA use and H. pylori infection on adverse gastroduodenal lesions.

Different gastric mucosa and CagA status of patients in India and Japan infected with Helicobacter pylori

BACKGROUND AND AIM

Despite similar incidence of Helicobacter pylori infection, the frequency of gastric cancer is sevenfold higher in Japan than in India. The objective of this work was to define differences in H. pylori-induced gastritis and to identify the bacterial virulence factors involved.

MATERIALS AND METHODS

We prospectively enrolled 353 consecutive patients who underwent endoscopy and received three gastric biopsies in Tokyo, Japan, and Hyderabad, India. Immunohistochemistry against H. pylori and East Asian CagA and hematoxylin-eosin and Giemsa stain were used to examine gastric mucosal biopsy specimens. Histological scores were assessed in accordance with the updated Sydney System. Subjects with H. pylori infection were matched by age and sex to compare histopathology and bacterial virulence.

RESULTS

Sixty patients infected with H. pylori were prospectively selected. Median histological scores for neutrophil and mononuclear cell infiltration and for atrophy were significantly higher in Japan than in India (neutrophils 4.0 vs 3.0, p < 0.01; mononuclear cells 5.0 vs 4.5, p = 0.03; atrophy 3.0 vs 2.0, p < 0.01, respectively). Scores for H. pylori density and intestinal metaplasia were also higher in Japan, albeit without statistical significance (H. pylori 5.0 vs 3.0, p = 0.08; intestinal metaplasia 0.0 vs 0.0, p = 0.08). Prevalence of East Asian CagA-positive H. pylori was significantly higher in Japan (73.3 vs 0.0 %, p < 0.01).

CONCLUSION

The significantly higher prevalence of histologically severe gastritis and East Asian CagA in patients from Japan with H. pylori infection may be involved in the pathogenesis of gastric cancer.

Is continuation of antiplatelets until coronary artery bypass safe in Asians?

Background

Controversies have arisen about the risks of discontinuing antiplatelets prior to coronary artery bypass grafting.

Methods

We retrospectively studied the effects of different strategies of antiplatelet discontinuation prior to coronary artery bypass on perioperative bleeding and major adverse cardiovascular events in Asian patients in a single center in Singapore.

Results

402 patients were divided into 4 groups: group A had no antiplatelets before surgery; antiplatelets were stopped for 5–7 days in group B; 2–4 days in group C; and 0–1 day in group D. Compared to group B, group D had longer intensive care unit stays and more intraoperative transfusions of blood ( p = 0.006) and blood products ( p < 0.05). The 1-year major adverse cardiovascular event rate was higher in groups A and D ( p = 0.027). Stopping antiplatelets within 24 h of surgery was one of multiple independent predictors of intraoperative transfusion but not the 1-year major adverse cardiovascular event rate. Patients on aspirin alone had less intraoperative transfusion of platelets and postoperative minor bleeding than those on combined therapy.

Conclusion

Continuation of antiplatelets until 2 days before coronary artery bypass in Asian patients in our institution is unlikely to increase the risks of bleeding and perioperative transfusion. Taking antiplatelets within 24 h of surgery seems to be associated with a higher rate of 1-year major adverse cardiovascular events and bleeding, and an increased risk of blood product transfusion. Thirty-day and 1-year major adverse cardiovascular event rates were higher in patients without antiplatelet treatment.

Risk assessment and aspirin use in Asian and Western populations

Objective

The aim of this review was to examine aspirin utilization, cardiovascular risk estimation, and clinical evidence for aspirin prophylaxis in Asian versus Western countries.

Methods

A literature search was performed using PubMed and the key terms “aspirin” and “Asia” or “Western”.

Results

Despite the growing burden of cardiovascular disease (CVD), aspirin is underutilized in high-risk patients in both Asian and Western countries. A number of risk estimation scores are available; however, validation is needed in countries such as Japan, India, and in South Asia. Underutilization of aspirin in Asia may be linked to an overestimation of bleeding risks. It is possible that a higher prevalence of Helicobacter pylori infection and genetic differences may make Asians more susceptible to gastrointestinal bleeding. Very low aspirin doses and even the wider use of gastroprotective agents may be the optimal approach to high-risk patients in Asia.

Conclusions

Based on the current evidence, aspirin should be used for CVD prevention when the risk:benefit ratio is favorable. A number of trials are underway, including the Diabetic Atherosclerosis Prevention by Cilostazol and Japanese Primary Prevention Project, which will provide key data on the benefits of aspirin in Asian patients at risk of CVD, and may improve aspirin utilization and risk estimation.

Differences in peptic ulcer between the East and the West

PUD affects both the East and the West. The magnitude of the problem, however, varies within these regions. The study of peptic ulcer epidemiology is impeded by the paucity of general population-based data, invasiveness of diagnostic tests, and variable access to testing facilities. As such, direct comparisons of PUD epidemiology between the East and the West are difficult. The prevalence rates of H pylori are highly variable and depend greatly on the local sanitation conditions. The use of NSAIDs and aspirin is ubiquitous and increasing especially for the antiplatelet activity of aspirin in the prophylaxis of cardiovascular events. There is evidence that pharmacogenetics play a role in susceptibility to the ulcerogenic properties of NSAIDs. The prevalence of PUD parallels the risk factors, but emerging in both the East and the West is idiopathic PUD, now a substantial proportion of ulcers in areas of declining H pylori infection. Genetic polymorphisms affect the efficacy of treatment using PPIs. Local H pylori resistance rates also influence the eradication success rates.

Role of cyclooxygenase-2 functional gene polymorphisms in Helicobacter pylori induced gastritis and gastric atrophy

In India, the role of host genetic factors is poorly studied for Helicobacter pylori associated diseases. Therefore, we evaluated the association of functionally relevant COX-2 gene polymorphisms (-765 G>C and +8473 T>C) in gastritis and precancerous lesions susceptibility. After upper GI endoscopy, 130 rapid urease test positive patients with non-ulcer dyspepsia, also showed positivity for H. pylori using modified Geimsa staining and anti-CagA IgG serology were included. All patients and 260 asymptomatic controls were genotyped for COX-2 variations using PCR-RFLP. COX-2 -765 (GC+CC) genotypes, -765 C allele, +8473 CC genotype, +8473 (TC+CC) genotypes, +8473 C allele, and variant haplotypes imparted high risk for gastritis (P = 0.036, OR = 1.82; P = 0.007, 1.92; P = 0.025, OR = 2.13; P = 0.017, OR = 1.80; P = 0.017, OR = 1.45; P = 0.010, OR = 2.40; P = 0.023, OR = 1.50 and P = 0.012, OR = 2.20 folds, respectively). In contrast, COX-2 -765 C allele carriers had low risk for lymphocyte (P = 0.020, OR = 0.35), plasma cell infiltrations (P = 0.016, OR = 0.33), and gastric atrophy (GA) development (P = 0.019, OR = 0.35). In conclusion, COX-2 variant allele/genotype/haplotype carriers may be at high risk for gastritis. However, COX-2 -765 C allele carriers may be at low risk for GA development.

Genetic association of interleukin-1 haplotypes with gastritis and precancerous lesions in North Indians

BACKGROUND

We evaluated the association of functional variants of IL-1 genes with the development of gastritis and precancerous lesions, which are known to be influenced by inflammatory response against Helicobacter pylori.

METHODS

After upper gastrointestinal (GI) endoscopy, 120 patients with gastritis were tested for H. pylori infection using rapid urease test, modified Giemsa staining and IgG anti-CagA ELISA. All patients and 243 healthy controls were genotyped for IL-1B (-511 C/T) and IL-IRN (VNTR) genes using PCR-RFLP/PCR.

RESULTS

IL-1B: (-511 C/T) genotype/allele were not associated with gastritis. IL-1RN 1/2 genotype carriers had susceptibility to gastritis (p=0.025, OR=1.7). Individuals with the IL-1RN 1/1 genotype (p=0.05, OR=0.65) and IL-1B -511*T-IL-1RN *1 haplotype were at low risk for gastritis (p=0.043, OR=0.72). High secretor haplotype combinations (C1-/T2+, C1-T1+ and T1+/T2+) did not influence neutrophilic infiltration, glandular atrophy or intestinal metaplasia.

CONCLUSIONS

We identified that individuals with the IL-1RN 1/2 genotype had increased risk for gastritis. IL-1B -511*T-IL-1RN *1 (T1) haplotype carriers were at decreased risk for gastritis and no significant association was observed for precancerous lesions in North Indians.

TC1(C8orf4) correlates with Wnt/beta-catenin target genes and aggressive biological behavior in gastric cancer

PURPOSE

We have recently reported that TC1(C8orf4), a small protein present in vertebrates, functions as a novel regulator of the Wnt/beta-catenin pathway. TC1 up-regulates beta-catenin target genes that are implicated in the aggressive behavior of cancers. Our aim was to investigate the clinical and pathobiological relevance of TC1 in gastric cancer.

EXPERIMENTAL DESIGN

The expression of TC1 was analyzed using tissue microarray in correlation with clinicopathologic variables and beta-catenin target genes in 299 gastric cancers. The biological effects of TC1 on Matrigel invasiveness and the proliferation of cancer cells were analyzed. TC1 expression was analyzed in gastric cancer cells after serial peritoneal implantation in nude mice.

RESULTS

TC1 expression was present in 111 carcinomas (37.1%), correlating with tumor stage (P < 0.002), poor differentiation (P < 0.001), lymphatic infiltration (P < 0.005), and lymph node metastasis (P < 0.006). TC1 also correlated with poor survival in diffuse type carcinomas (P < 0.0001), and even in patients with lymph node metastasis (P < 0.0014). TC1 also correlated with the expression of beta-catenin target genes including laminin gamma2, metalloproteinase-7 and metalloproteinase-14, cyclin D1, c-Met, and CD44. TC1 enhanced Matrigel invasiveness and proliferation, supporting its role in the aggressive biological behavior of cancers. The expression of TC1 increased in MKN45 cells after serial peritoneal seeding in nude mice.

CONCLUSIONS

Our data suggests that TC1 coordinates the up-regulation of Wnt/beta-catenin target genes that are implicated in the aggressive biological behavior of cancers. The strong clinical relevance, even in patients with lymph node metastasis, suggested that TC1 could be a potential therapeutic target of advanced gastric cancers.

Association of Toll-like receptor-4 (Asp299Gly and Thr399Ileu) gene polymorphisms with gastritis and precancerous lesions

A Toll-like receptor-4 (TLR-4) Asp299Gly and Thr399Ileu substitution reduces responsiveness to Helicobacter pylori (H. pylori) lipopolysaccharide. CagA+ strains of H. pylori are known to be associated with gastroduodenal diseases. Therefore we aimed to evaluate association of TLR-4 substitutions and CagA seropositivity with gastritis and precancerous lesions in a northern Indian population. After upper gastrointestinal endoscopy, 130 rapid urease test (RUT)-positive patients with nonulcer dyspepsia (NUD) were included. Patients with NUD were also screened for H. pylori infection using modified Giemsa staining and anti-CagA IgG enzyme-linked immunoabsorbent assay. All patients and 200 asymptomatic control subjects were genotyped for TLR-4 substitutions using polymerase chain reaction-restriction fragment length polymorphism. We observed that frequencies of TLR-4 Asp299Gly variants were comparable between patients and control subjects, and also between positive and negative groups of precancerous lesions in patients. Frequencies of TLR-4 399Ileu allele (8% vs 3%, p = 0.008) and Asp299-Ileu399 haplotype (6.5% vs 3%, p = 0.022) were higher in patients than in control subjects at risk for gastritis (OR = 2.6 and 2.5, respectively). TLR-4 399Ileu allele carriers had higher risk for plasma cell infiltration (p = 0.023, OR = 10.6) that led to atrophy (p = 0.028, OR = 4.2) and intestinal metaplasia (p = 0.009, OR = 4.7). CagA positivity was more frequently associated with lymphoid follicle formation (p = 0.033, OR = 2.53). In conclusion TLR-4 Thr399Ileu substitution may be a risk factor for gastritis and precancerous lesions. CagA positivity may be a risk factor for lymphoid follicle development but not for other precancerous lesions in a northern Indian population.

Relationship of Helicobacter pylori to Bcl-2 family expression, DNA content, and pathological characteristics of gastric cancer

BACKGROUND

Despite the fact that the association of Helicobacter pylori with an increased risk of gastric cancer has been well documented, the exact mechanisms of this association have not been fully elucidated. Scarce data on H. pylori infection and its relationship with the different pathological characteristics are available in Egypt.

AIM OF THE STUDY

The rationale of the present study was to determine the prevalence of H. pylori in a group of gastric cancer patients and to analyze the relationship between H. pylori infection with the different pathological characteristics including the types of gastric cancer and tumor location within the stomach, in addition, to investigate the Bcl-2 and Bax expressions along with DNA flow cytometric analysis in the gastric cancer patients with and without H. pylori infection.

METHODS

Samples were obtained from 66 consecutive patients with gastric cancer (46 males and 20 females). The youngest patient was 20 yr old, the oldest 76 yr with mean age of 52.8 yr. The samples were subjected for histopathological characterization, H. pylori detection, DNA flow cytometric analysis, and Bcl-2 and Bax expressions detection, in addition to apoptosis analysis.

RESULTS

The obtained results showed that the H. pylori infection was found in 38/66 (57.6%) [Odds ratio=1.357 with 95% confidence interval (CI) 0.84-2.2]. There was a statistical significance for Bcl-2, Bax, and apoptosis with H. pylori status (p = 0.009, 0.008, 0.032, respectively). On the other hand, There was a statistical significance for H. pylori infection with the disease grade (p = 0.015) and lymph node metastasis (p = 0.05). No statistical significance was found between H. pylori status with the patients' age, gender, tumor site, tumor type, depth of invasion, and stromal reaction.

CONCLUSIONS

These data may indicate that the H. pylori infection not only contributes in the disease formation through the apoptosis dysregulation but also takes a part in the disease dissemination and progression. In addition, it may reflect a biologic, pathogenic, and ethnic background affecting the relationship of H. pylori infection to gastric cancer in the Egyptian patients. A high rate of smoking in Egypt and the diet are important factors that may affect such background. Further studies are warranted.

Helicobacter pylori infection is associated with a high incidence of intestinal metaplasia in the gastric mucosa of patients at inner-city hospitals in New York

Gastric carcinogenesis is a multistep process progressing from chronic gastritis, through glandular atrophy (GA), intestinal metaplasia (IM) and dysplasia. Infection of the stomach with H. pylori increases the risk of developing gastric cancer. Few studies have examined the degree to which Hp-induced changes occur in specific populations. In the present study, we examined the association between Hp infection and histological changes in the gastric mucosa of patients at two inner-city hospitals in New York. Patients enrolled in this study were undergoing endoscopy for gastrointestinal complaints. One antral biopsy was taken for detecting and genotyping Hp by PCR. Additional biopsies were taken from the antrum and fundic region for histological analysis and were scored with respect to acute and chronic inflammation, GA, IM and Hp infestation according to the Sydney classification. Hp strains infecting these patients were genotyped with respect to the expression of Hp virulence factors including VacA, CagA, and BabA2. Samples were collected from 126 patients at Kings County Hospital in Brooklyn and St. John's Episcopal Hospital in Queens. Hp infection rates were highest in Blacks (41.6%) and Hispanics (29.4%) and lowest in Caucasians (18.8%). Scores for acute and chronic inflammation and IM were higher in Hp-infected individuals in both the antrum and fundic regions, whereas Hp infection did not affect the incidence or intensity of GA. In Hp-infected individuals, the incidence of IM was greater in the antrum (Hp-infected 37.8% vs. non-infected 9.2%, p < 0.05) and fundic region (Hp-infected 15.1% vs. noninfected 1.8%, p < 0.05). Genotyping of the Hp strains infecting these patients revealed that the predominant VacA allele was s1 bm 1 and that the CagA gene was present in 69.8% of Hp-infected samples. Interestingly, the BabA2 gene was detected in only four samples (9.3%). The incidence of IM in the antrum was higher in CagA + samples when compared with CagA- samples (52.2% vs. 15.4%, respectively). Our findings indicate that the virulent Hp strain infecting minority patients treated at inner-city hospitals in New York City is associated with a high incidence of IM and that these patients may be at greater risk for developing gastric cancer than the general population.

H pylori infection among 1000 southern Iranian dyspeptic patients

AIM: To describe the frequency of H pylori infection among 1000 southern Iranian dyspeptic patients.

METHODS: A prospective study was performed in a referral hospital in south of Iran from 1999 to 2005. One thousand dyspeptic patients (518 males, mean ± SD age of 49.12 ± 12.82 years) consecutively underwent upper gastrointestinal endoscopy. Multiple gastric antral biopsy samples were taken from all patients for rapid urease test and histopathologic examination (96.9% satisfactory samples). Patients were considered H pylori-infected if one or both tests were positive.

RESULTS: Six hundred and seventy-one patients (67.1%, 95% confidence interval [CI]: 64.2%-70.0%) were H pylori-infected. H pylori positivity was significantly more frequent in patients with peptic ulcer disease (PUD) than in those with non-ulcer dyspepsia (P < 0.001). Male-to-female ratio for duodenal and gastric ulcers was 2.7:1 and 1.5:1, respectively. Moreover, the duodenal-to-gastric ulcer ratio was 1.95:1. The frequency of H pylori infection among those with endoscopic diagnosis of gastritis, duodenal ulcer, gastric ulcer, and normal mucosa was 70.1% (398/568), 86.2% (150/174), 71.9% (64/89), and 33.5% (54/161), respectively. H pylori infection, male sex, and older age were independently associated with PUD in multivariate analysis. H pylori positivity was associated with chronic gastritis, and chronic active gastritis with odds ratios of 34.21 (95% CI: 12.19%-96.03%) and 81.21 (95% CI: 28.85%-228.55%), respectively.

CONCLUSION: H pylori and PUD are highly frequent in dyspeptic patients from south of Iran. H pylori is a cardinal risk factor for chronic active or inactive gastritis.

Extensive intestinal metaplasia in gastric carcinoma and in other lesions requiring surgery: a study of 3,421 gastrectomy specimens from dwellers of the Atlantic and Pacific basins

BACKGROUND

Extensive intestinal metaplasia (EIM) has been reported in gastrectomies from patients dwelling in the Pacific and Atlantic basins.

AIMS

To compare all the results in an attempt to explain the findings.

METHOD

All sections from 3,421 gastrectomies were reviewed at various hospitals: 1946 in the Atlantic and 1475 in the Pacific basin. Sections with EIM showed IM encompassing one or more entire low power field (>or=5 mm in length/section) in one or more section.

RESULTS

In the Atlantic basin, EIM was present in 18.8% (153 of 814) of specimens with intestinal carcinoma (IC) and in 10.3% (65 of 630) of those with diffuse carcinoma (DC). In the Pacific basin, EIM was found in 62.9% (412 of 655) of gastrectomies with IC and in 33.3% (160 of 481) of those with DC. The numbers of specimens with EIM were significantly higher in the Pacific than in the Atlantic basin for both carcinoma phenotypes, particularly among elderly patients (>or=60 years).

CONCLUSIONS

The proportion of gastrectomies with EIM was higher among populations at a higher gastric cancer risk than in those with a lower cancer risk. EIM was mostly associated with IC rather than DC or with miscellaneous gastric diseases (841 control gastrectomies) in both basins. The proportion of gastrectomies with EIM was significantly higher in Vancouver than in New York and in Santiago de Chile than in Buenos Aires, even though these populations reside at approximately the same geographical latitude, but in different basins. Environmental factors seem to accelerate the evolution of EIM.