Barrett's esophagus and the presence of Helicobacter pylori

Disease trends after Helicobacter pylori eradication based on Japanese nationwide claims and the health check-up database

BACKGROUND

Helicobacter pylori (H. pylori) infection is a risk factor for many diseases, including peptic ulcer disease and gastric cancer. While H. pylori eradication therapy can prevent these diseases, potentially unfavorable effects of eradication therapy have also been reported in some diseases, such as gastroesophageal reflux disease (GERD), Barrett’s esophagus (BE), inflammatory bowel disease (IBD), allergic diseases, and metabolic diseases. Consequently, both positive and negative impacts should be considered when assessing the effects of H. pylori eradication therapy.

AIM

To compare the incidence of these diseases before and after H. pylori eradication and to comprehensively assess its effects.

METHODS

This retrospective cohort study used a Japanese nationwide health claims database (April 2009-March 2020), developed by the Japanese Ministry of Health, Labour and Welfare. The database contained almost all health insurance claims data issued in Japan, and specific health check-up data for individuals who took the check-ups. Descriptive statistics were used for the analyses. Patients who received primary eradication therapy were defined as those prescribed medi-cation for H. pylori eradication. New diagnoses, defined as incidence of upper gastrointestinal diseases and IBD, and prevalence of allergic diseases were compared before and after eradication. The incidence and prevalence of each disease were also compared between the 3-year period before eradication (from the 4^th to the 2^nd year prior to the year of eradication) and the 3-year period after eradication (from the 1^st to the 3^rd year after the year of eradication) based on the age category and calendar year and month. Changes in body mass index and proportion of patients with metabolic syndrome (MS) were examined before and after eradication.

RESULTS

We identified 5219731 patients who received primary eradication therapy. The 65-69 years age group had the greatest number of patients in both sexes. There was no significant increase in the incidence of GERD after eradication when considering the effects of aging and reporting period. However, the incidence of BE was higher in the 3-year period after eradication than in the 3-year period before eradication for all age categories (0.02%-0.10% vs < 0.01%-0.05%). The incidence of IBD and prevalence of allergic disease were also higher after eradication. In contrast, the incidence of gastric and duodenal ulcers and gastritis was reduced after eradication. In patients with at least one entry of health check-up data (1701111 patients), the percentage of patients with MS showed a slight increase following eradication (11.0% in the year of eradication and 12.2% after 5 years).

CONCLUSION

The results suggest that H. pylori eradication therapy reduces peptic ulcers and gastritis; however, it is associated with increased incidence of several other chronic diseases.

Association of Barrett's esophagus with Helicobacter pylori infection: a meta-analysis

Background and Aims:

Barrett’s esophagus (BE) is the only recognized precursor for esophageal adenocarcinoma. Helicobacter pylori (H. pylori) infection is a major contributing factor towards upper gastrointestinal diseases, but its relationship with BE remains controversial. Some previous studies suggested that H. pylori infection negatively correlated with BE, while others did not. This may be attributed to the difference in the selection of control groups among studies. The present meta-analysis aims to clarify their association by combining all available data from well-designed studies.

Methods:

The PubMed, EMBASE, and Cochrane Library databases were searched. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled by a random-effects model. Heterogeneity was evaluated using the Cochran’s Q test and I² statistics. Meta-regression, subgroup, and leave-one-out sensitivity analyses were employed to explore the sources of heterogeneity.

Results:

Twenty-four studies with 1,354,369 participants were included. Meta-analysis found that patients with BE had a significantly lower prevalence of H. pylori infection than those without (OR = 0.53, 95% CI = 0.45–0.64; p < 0.001). The heterogeneity was statistically significant (I² = 79%; p < 0.001). Meta-regression, subgroup, and leave-one-out sensitivity analyses did not find any source of heterogeneity. Meta-analysis of 7 studies demonstrated that CagA-positive H. pylori infection inversely correlated with BE (OR = 0.25, 95% CI = 0.15–0.44; p = 0.000), but not CagA-negative H. pylori infection (OR = 1.22, 95% CI = 0.90–1.67; p = 0.206). Meta-analysis of 4 studies also demonstrated that H. pylori infection inversely correlated with LSBE (OR = 0.39, 95% CI = 0.18–0.86; p = 0.019), but not SSBE (OR = 0.73, 95% CI = 0.30–1.77; p = 0.484).

Conclusion:

H. pylori infection negatively correlates with BE. More experimental studies should be necessary to elucidate the potential mechanisms in future.

Narrative review of the role of gastroenterologist in the diagnosis, treatment and palliation in gastric and gastroesophageal cancer

Esophageal cancer (EC) and gastric cancer (GC) carry a high mortality rate. Unfortunately, a majority of patients are asymptomatic and at the time of diagnosis, the disease may invariably be in its advanced stages with limited curative options. Thus, it is imperative to recognize certain risk factors including gastroesophageal reflux disease (GERD), male gender, pre-existing Barrett’s esophagus, smoking history, obesity, Helicobacter pylori infection, atrophic gastritis among others for both EC and GC, intervene on time with screening and surveillance modalities if indicated and optimize treatment plans. With advances in endoscopic techniques, early neoplastic lesions are increasingly managed by gastroenterologists, offering an alternative to surgery. The gold standard for diagnosis of EC and GC is high definition endoscopy with adequate targeted biopsies. Endoscopic ultrasound (EUS) is a key in the staging of early cancers dictating the pathway for treatment options. We also play a key role in palliation cases with the aim to reduce the symptoms like nausea, vomiting and even when possible, restore oral intake and improve nutrition in both advanced GC and EC. This review article discusses the risk factors, diagnostic and endoscopic treatment modalities of early EC and GC and palliation of advanced cancer where gastroenterologists play a key role.

Helicobacter pylori infection reduces the risk of Barrett's esophagus: A meta-analysis and systematic review

INTRODUCTION

The prevalence of Helicobacter pylori infection (HPI) has been decreasing in developed countries, with an increasing prevalence of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) at the same time. The aim of our meta-analysis was to quantify the risk of BE in the context of HPI.

METHODS

A systematic search was conducted in 3 databases for studies on BE with data on prevalence of HPI from inception until December 2016. Odds ratios for BE in HPI were calculated by the random effects model with subgroup analyses for geographical location, presence of dysplasia in BE, and length of the BE segment.

RESULTS

Seventy-two studies were included in the meta-analysis, including 84 717 BE cases and 390 749 controls. The overall analysis showed that HPI reduces the risk of BE; OR = 0.68 (95% CI: 0.58-0.79, P < .001). Subgroup analyses revealed risk reduction in Asia OR = 0.53 (95% CI: 0.33-0.84, P = .007), Australia OR = 0.56 (95% CI: 0.39-0.80, P = .002), Europe OR = 0.77 (95% CI: 0.60-0.98, P = .035), and North-America OR = 0.59 (95% CI: 0.47-0.74, P < .001). The risk was significantly reduced for dysplastic BE, OR = 0.37 (95% CI: 0.26-0.51, P < .001) for non-dysplastic BE, OR = 0.51 (95% CI: 0.35-0.75, P = .001), and for long segment BE, OR = 0.25 (95% CI: 0.11-0.59, P = .001) in case of HPI.

CONCLUSIONS

This extensive meta-analysis provides additional evidence that HPI is associated with reduced risk of BE. Subgroup analyses confirmed that this risk reduction is independent of geographical location. HPI is associated with significantly lower risk of dysplastic, non-dysplastic, and long segment BE.

Helicobacter pylori induces caudal-type homeobox protein 2 and cyclooxygenase 2 expression by modulating microRNAs in esophageal epithelial cells

Dysregulation of microRNAs (miRNAs) has been linked to virulence factors of Helicobacter pylori. The role of H. pylori in esophageal disease has not been clearly defined. We previously reported that H. pylori esophageal colonization promotes the incidence of Barrett's esophagus and esophageal adenocarcinoma in vivo. Here, we studied the direct effects of H. pylori on the transformation of esophageal epithelial cells, with particular focus on whether H. pylori exerts its effects by modulating miRNAs and their downstream target genes. The normal human esophageal cell line HET‐1A was chronically exposed to H. pylori extract and/or acidified deoxycholic acid for up to 36 weeks. The miRNA profiles of the esophageal epithelial cells associated with H. pylori infection were determined by microarray analysis. We found that chronic H. pylori exposure promoted acidified deoxycholic acid‐induced morphological changes in HET‐1A cells, along with aberrant overexpression of intestinal metaplasia markers and tumorigenic factors, including caudal‐type homeobox protein 2 (CDX2), mucin 2, and cyclooxygenase 2 (COX2). Helicobacter pylori modified the miRNA profiles of esophageal epithelial cells, particularly aberrant silencing of miR‐212‐3p and miR‐361‐3p. Moreover, in biopsies from Barrett's esophagus patients, esophageal H. pylori colonization was associated with a significant decrease in miR‐212‐3p and miR‐361‐3p expression. Furthermore, we identified COX2 as a target of miR‐212‐3p, and CDX2 as a target of miR‐361‐3p. Helicobacter pylori infection of esophageal epithelial cells was associated with miRNA‐mediated upregulation of oncoprotein CDX2 and COX2. Our observations provide new evidence about the molecular mechanisms underlying the association between H. pylori infection and esophageal carcinogenesis.

Effect of Helicobacter pylori infection on esophageal epithelial cells in vitro

AIM: To investigate the effect of Helicobacter pylori (H. pylori) exposure on esophageal cell line OE33 in vitro.

METHODS: Human esophageal adenocarcinoma cell line OE33 was cultured and treated with 200 mmol/L acidified deoxycholic acid (pH 6.0) or infected with H. pylori 26695. After treatment or infection, cell viability was tested by CCK-8 assay; cell apoptosis was determined by flow cytometric analysis with Annexin V-FITC/7-AAD; the mRNA expression of CDX2 and MUC2 was assessed by real time-PCR; nuclear factor-kB (NF-kB)-associated proteins were examined by Western blot; and the DNA binding activity of NF-kB was evaluated by electrophoretic mobility shift assay (EMSA).

RESULTS: The viability of OE33 cells was reduced significantly after treatment with acidified deoxycholic acid or infection with H. pylori compared with negative controls (both P < 0.01). Treatment with acidified deoxycholic acid or infection with H. pylori induced apoptosis and increased the mRNA expression of CDX2 and MUC2 (all P < 0.01). Both H. pylori infection and treatment with acidified deoxycholic acid enhanced the DNA binding activity of NF-kB and the protein expression of phosphorylated IkBa and P65 in esophageal epithelial cells.

CONCLUSION: H. pylori infection reduces cell viability, induces apoptosis, and increases the expression of CDX2 and MUC2 and the activation of NF-kB in esophageal epithelial cells.

The association between Barrett's esophagus and Helicobacter pylori infection: a meta-analysis

OBJECTIVE

The effect of Helicobacter pylori on Barrett's esophagus is poorly understood. We conducted a meta-analysis to summarize the existing literature examining the effect that H. pylori has on Barrett's esophagus.

DESIGN

 We performed a comprehensive search to identify studies pertaining to the association between H. pylori and Barrett's esophagus. We conducted meta-regression analyses to identify sources of variation in the effect of H. pylori on Barrett's esophagus.

RESULTS

 Our analysis included a total of 49 studies that examined the effect of H. pylori on Barrett's esophagus and seven studies that examined the effect of cag A positivity on Barrett's esophagus. Overall, H. pylori, and even more so cag A, tended to be protective for Barrett's esophagus in most studies; however, there was obvious heterogeneity across studies. The effect of H. pylori on Barrett's esophagus varied by geographic location and in the presence of selection and information biases. Only four studies were found without obvious selection and information bias, and these showed a protective effect of H. pylori on Barrett's esophagus (Relative risk = 0.46 [95% CI: 0.35, 0.60]).

CONCLUSIONS

 Estimates for the effect of H. pylori on Barrett's esophagus were heterogeneous across studies. We identified selection and information bias as potential sources of this heterogeneity. Few studies without obvious selection and information bias have been conducted to examine the effect of H. pylori on Barrett's esophagus, but in these, H. pylori infection is associated with a reduced risk of Barrett's esophagus.

High frequency of Helicobacter pylori in the esophageal mucosa of dyspeptic patients and its possible association with histopathological alterations

BACKGROUND

Helicobacter pylori gastric colonization is known to be high in symptomatic subjects. However, only a few reports on the presence of H. pylori in the esophageal mucosa have been published. The aim of this study was to assess the frequency of H. pylori in the esophagus of dyspeptic patients and its association with histopathology.

METHODS

The presence of H. pylori in the gastroesophageal mucosa was detected by fluorescence in situ hybridization (FISH) and PCR analysis of DNA extracted from gastric and esophageal biopsies of 82 symptomatic patients, using genus- and species-specific PCR primers. Alterations in the gastroesophageal mucosa were assessed by conventional histological techniques.

RESULTS

H. pylori in the stomach was detected by PCR and FISH, respectively, in 61% (n=43) and 90% (n=63) of dyspeptic patients, and in the esophagus in 70% (n=44) and 73% (n=46). The prevalence of cagA-positive strains by PCR varied from 50% (n=35) in the gastric mucosa to 65% (n=41) in the esophageal mucosa. By combining the results of both methods, H. pylori was present in the gastroesophageal mucosa in 86% (n=68) of patients. The association of the presence of bacteria, including H. pylori, in the esophageal mucosa with histopathological alterations was statistically significant between microabscesses and bacteria (r=0.656, p<0.0001) and PCR detection and pseudogoblet cells (r=0.25, p<0.047).

CONCLUSIONS

This is the first report of the occurrence of H. pylori in the esophageal mucosa from dyspeptic Venezuelan patients. These results demonstrate the high prevalence of H. pylori in the esophagus, and its presence was correlated with signs of inflammation.

Effect of Helicobacter pylori infection on Barrett's esophagus and esophageal adenocarcinoma formation in a rat model of chronic gastroesophageal reflux

OBJECTIVES

To investigate the relationship between Helicobacter pylori infection and Barrett's esophagus (BE), a rat model of chronic gastroesophageal reflux with H. pylori infection was established and the degree of inflammation, incidence of BE and esophageal adenocarcinoma (EA) were evaluated.

METHODS

Eight-week-old male specific-pathogen-free SD rats were divided into five groups randomly: pseudo-operation group; esophagojejunum anastomosis (EJA) group; EJA with H. pylori infection group; EJA with H. pylori infection and celecoxib-treated group; EJA with celecoxib-treated group. Rats were kept for 30 weeks after surgery. Esophageal lesion was evaluated grossly and microscopically. The expression of COX-2 and CDX2 was determined by RT-PCR and immunohistochemistry staining. The level of PGE₂ was assessed by enzyme-linked immunosorbent assay.

RESULTS

Esophageal mucosal injury in the group of EJA with H. pylori infection was decreased than that in EJA group (p < .05). The incidence of BE and EA in rats undergoing EJA with H. pylori infection was increased than in rats undergoing EJA with no statistical difference. Celecoxib treatment decreased the incidence of EA in rats undergoing EJA with H. pylori infection (p < .05). The expression of CDX2 mRNA was decreased in rats with H. pylori infection or treated with celecoxib than in the rats of pseudo-operation group (p < .05). When compared with those in rats of pseudo-operation group, the expression of COX-2 mRNA and the level of PGE₂ were upregulated in rats undergoing EJA irrespective of H. pylori infection (p < .05) and downregulated in rats treated with celecoxib (p < .05). When H. pylori colonized in esophagus, the severity of inflammation and the incidence of BE and EA were increased significantly. Higher levels of COX-2 expression and PGE₂ were detected in rats with esophageal H. pylori colonization.

CONCLUSIONS

When H. pylori infect in stomach, it may reduce the severity of inflammation. However, when colonizes in esophagus, H. pylori increases the severity of esophageal inflammation and the incidence of BE and EA. Celecoxib administration attenuates the incidence of EA by inhibiting COX-2 expression.

Helicobacter pylori and esophageal cancer risk: a meta-analysis

We conducted this meta-analysis to examine the association between Helicobacter pylori and esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma. We searched the PubMed database, the ISI database, and the references of the selected articles. Case-control or nested case-control studies were selected if they used serology or endoscopic methods to detect H. pylori in the stomach and if control subjects were not restricted to upper gastrointestinal tract cancer or peptic ulcer disease patients. A total of 19 studies were used for this analysis. Summary odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using the DerSimonian-Laird method. Q statistics and I(2) statistics were calculated to examine heterogeneity. Subgroup analyses were conducted by CagA status. For EAC, the summary OR (95% CI) was 0.56 (0.46-0.68). There was little heterogeneity among studies (I(2) = 15%). Further analysis showed that colonization with CagA-positive strains was inversely associated with EAC risk (OR, 0.41; 95% CI, 0.28-0.62) but colonization with CagA-negative strains was not (OR, 1.08; 95% CI, 0.76-1.53). For esophageal squamous cell carcinoma, the summary OR (95% CI) was 1.10 (0.78-1.55). However, there was substantial heterogeneity among studies (I(2) = 73%), with statistically significant associations in both directions. Our results suggest an inverse association between CagA-positive H. pylori colonization and risk of EAC. The prominent decline of H. pylori colonization in the past few decades may be partly responsible for the recent increase in EAC incidence in Western countries.

Helicobacter pylori infection and severity of reflux-induced esophageal disease in a cohort of patients with columnar-lined esophagus

The relationship between Helicobacter pylori infection and reflux-induced esophageal diseased is controversial. We examined esophageal disease severity in patients with columnar-lined esophagus and compared results between patients with and without Helicobacter pylori infection. Medical records of 1000 patients diagnosed with columnar-lined esophagus were examined. Endoscopic and histological findings of reflux-induced esophageal disease were compared between H. pylori-positive and H. pylori-negative patients. Four hundred twenty-nine patients (42.9%) showed evidence of H. pylori status, of whom 239 (55.7%) were positive and 190 (44.3%) negative. There were no significant differences in length of columnar-lined segment (P = 0.305), frequency of associated esophagitis (P = 0.583), or presence of gastroduodenal inflammation (P = 0.335, P = 0.131) between the two groups. Histological grade of esophageal disease severity was similar between them, with no statistically significant differences (P = 0.231). We conclude that in patients with established columnar-lined esophagus, there appears to be no difference in severity of reflux-induced esophageal disease between those with and those without H. pylori infection.

Bacterial factors that mediate colonization of the stomach and virulence of Helicobacter pylori

Helicobacter pylori is a Gram-negative microaerophilic organism that colonizes the gastric mucosa of humans. Helicobacter pylori is one of the most common infections in humans and results in the development of gastritis in all infected individuals, although the majority of people are asymptomatic. A subset of infected people develop serious disease including duodenal ulceration and gastric cancer. Helicobacter pylori exhibits many striking characteristics. It lives in the hostile environment of the stomach and displays a very strict host and tissue tropism. Despite a vigorous immune response, infection persists for the lifetime of the host unless eradicated with antimicrobials. Why H. pylori is so pathogenic in some individuals and not in others is unknown but is thought to be due to a variety of host, environmental and bacterial factors. In this review, some of the bacterial factors that mediate colonization of the gastric mucosa and play a role in the pathogenesis of this organism have been considered.

Bacterial biota in reflux esophagitis and Barrett's esophagus

AIM

To identify the bacterial flora in conditions such as Barrettos esophagus and reflux esophagitis to determine if they are similar to normal esophageal flora.

METHODS

Using broad-range 16S rDNA PCR, esophageal biopsies were examined from 24 patients [9 with normal esophageal mucosa, 12 with gastroesophageal reflux disease (GERD), and 3 with Barrettos esophagus]. Two separate broad-range PCR reactions were performed for each patient, and the resulting products were cloned. In one patient with Barrettos esophagus, 99 PCR clones were analyzed.

RESULTS

Two separate clones were recovered from each patient (total = 48), representing 24 different species, with 14 species homologous to known bacteria, 5 homologous to unidentified bacteria, and 5 were not homologous (<97% identity) to any known bacterial 16S rDNA sequences. Seventeen species were found in the reflux esophagitis patients, 5 in the Barrettos esophagus patients, and 10 in normal esophagus patients. Further analysis concentrating on a single biopsy from an individual with Barrettos esophagus revealed the presence of 21 distinct bacterial species. Members of four phyla were represented, including Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria. Microscopic examination of each biopsy demonstrated bacteria in intimate association with the distal esophageal epithelium, suggesting that the presence of these bacteria is not transitory.

CONCLUSION

These findings provide evidence for a complex, residential bacterial population in esophageal reflux-related disorders. While much of this biota is present in the normal esophagus, more detailed comparisons may help identify potential disease associations.

CagA in Barrett's oesophagus in Colombia, a country with a high prevalence of gastric cancer

BACKGROUND

In the USA, atrophic gastritis and gastric cancer are rare, whereas gastro-oesophageal reflux disease (GERD) is common. Infection with Helicobacter pylori, especially a CagA positive strain, is unusual in patients with GERD/Barrett's oesophagus in the USA.

AIM

To examine the relation between Barrett's oesophagus and CagA positive H pylori in Colombia, a country with a high prevalence of CagA positive H pylori associated atrophic gastritis and gastric cancer.

METHODS

Helicobacter pylori and CagA status was determined among Colombian patients with long segment Barrett's oesophagus and a control group with simple H pylori gastritis. Helicobacter pylori status was determined using a triple stain and CagA status was determined by immunohistochemistry using a specific rabbit anti-CagA serum.

RESULTS

Gastric and oesophageal mucosal biopsies were obtained from 51 patients--39 men (mean age, 57.8 years; SD, 13.1) and 12 women (mean age, 51.8 years; SD, 14.4)--with documented long segment Barrett's oesophagus. The results were compared with 24 Colombian patients with H pylori gastritis without oesophageal disease. Thirty two patients with Barrett's oesophagus had active H pylori infection. CagA status was evaluated in a subset of 23 H pylori infected patients with Barrett's oesophagus, and was positive in eight of these patients compared with 19 of 24 controls (p = 0.01).

CONCLUSIONS

Although most Colombian patients with Barrett's oesophagus had H pylori infection, CagA positive infections were unusual. These data illustrate how consistent corpus inflammation reduces acid secretion, which prevents Barrett's oesophagus among those with abnormal gastro-oesophageal reflux barriers.

Epidemiologic risk factors for Barrett's esophagus and associated adenocarcinoma

The incidence of esophageal adenocarcinoma (AC) has increased dramatically in the Western world over the past 20 years and the majority of these cancers arise on the background of the preinvasive lesion Barrett's esophagus. The epidemiologic factors that contribute to an individual's susceptibility for Barrett's esophagus and associated cancer are likely to be multifactorial. However, the short time frame over which the incidence of adenocarcinoma has increased, and the increase across populations, provides a strong argument for environmental factors as etiologic agents, perhaps interacting with genetically determined characteristics that define personal susceptibility. In this review we discuss the epidemiologic evidence for the proposed demographic and environmental risk factors for the development of both Barrett's esophagus and AC. The current evidence suggests that significant risk factors include male sex, Caucasian race, and the presence of duodenogastroesophageal reflux disease. The susceptibility for reflux disease may in turn be influenced by factors such as obesity, the use of drugs that lower the lower-esophageal sphincter tone, and a protective effect of Helicobacter pylori colonization. There appears to be a weak association between smoking and AC. The role of dietary factors has not been studied adequately and deserves further attention. An understanding of the factors that predispose to the development and progression of Barrett's esophagus is crucial to the implementation of effective screening and prevention programs.

The role of cagA Helicobacter pylori strains in gastro-oesophageal reflux disease

BACKGROUND AND AIMS

The role of Helicobacter pylori infection in gastro-oesophageal reflux disease is controversial. The aim of this study was to evaluate the prevalence of colonization by cagA-positive and cagA-negative H. pylori strains in the spectrum of gastro-oesophageal reflux disease.

METHODS

A total of 108 patients (50 male/58 female; mean age, 50.3 years) with dyspepsia and peptic ulcer or erosive gastritis/duodenitis were categorized into patients without reflux and patients with reflux oesophagitis graded from I to IV. All patients underwent upper endoscopy with biopsies of the antrum. H. pylori was detected by histology, urease test and polymerase chain reaction. The cagA status was diagnosed in the gastric biopsy by polymerase chain reaction.

RESULTS

The overall prevalence of H. pylori colonization in patients with reflux was 68.6% and was 70.2% in those without oesophageal disease (P = 0.862). Colonization by cagA-positive strains was also not statistically different between the two groups (31.4% versus 40.4%, P = 0.332). However, patients with grades II-IV reflux oesophagitis were less colonized by the bacterium (36.4%) than patients with grade I oesophagitis (77.5%) (P = 0.009). H. pylori cagA-positive strains were also less likely to colonize the stomach of patients with grades II-IV oesophagitis (0%), than grade I reflux oesophagitis (40%) patients and controls (40.4%).

CONCLUSIONS

Infection of the stomach by H. pylori and especially by H. pylori cagA strains may play a protective role against the development of the most severe forms of gastro-oesophageal reflux disease.

The implications of Helicobacter pylori infection for gastroesophageal reflux disease: studies presented at Digestive Disease Week 2003

The relationship between Helicobacter pylori infection and gastroesophageal reflux disease (GERD) remains controversial. Over 20 studies presented at the 2003 Digestive Disease Week meeting examined the implications of H. pylori infection for GERD. Although the findings were not uniform, most of the studies presented indicated a negative association between the presence of H. pylori and the presence of GERD symptoms, signs, or complications. In addition, eradication of H. pylori infection was related to the emergence of GERD and its complications. However, most studies favored a role for H. pylori rather than GERD in the development of pathologic changes in the gastric cardia. Finally, a few studies suggested the intriguing possibility that the modulation of GERD by H. pylori could be through the effects of H. pylori eradication on weight gain.

Are carcinomas of the cardia oesophageal or gastric adenocarcinomas?

There is a clear relationship between Barrett's oesophagus and oesophageal adenocarcinoma, and between Helicobacter pylori and gastric cancer, but the histogenesis of cardiac adenocarcinomas is unknown. Some clues as to possible disease associations may be provided by the pattern of gastritis. In our study, we analysed gastritis associated with oesophageal, cardiac and gastric adenocarcinomas according to the Sydney classification. Chronic gastritis was more common in gastric (88%) than in cardiac (56%) and oesophageal adenocarcinomas (38%). H. pylori was significantly more prevalent in gastric (73%) than in cardiac (34%) or oesophageal (21%) adenocarcinomas. Our results show that factors other than H. pylori must be involved in the histogenesis of cardiac adenocarcinomas. As the pattern of gastritis and the clinical features of cardiac adenocarcinomas are more comparable to oesophageal carcinomas than gastric carcinomas, we speculate that most of these tumours share similar aetiological factors with oesophageal carcinomas.

Effect of Helicobacter pylori infection in Barrett's esophagus and the genesis of esophageal adenocarcinoma

The relation between Helicobacter pylori and gastroesophageal reflux disease is unclear. Recent reports have suggested a possible protective role for H. pylori, particularly in preventing the complications of gastroesophageal reflux disease (GERD). The purpose of this article is to present a brief overview of the recent literature regarding the role of H. pylori in the genesis of the complications of GERD, focusing on Barrett's esophagus and esophageal adenocarcinoma. The prevalence of H. pylori infection in the population of the West is around 40% and is not different in cohorts of patients with GERD. When the infection induces pangastritis or corpus-predominant gastritis, there may be concomitant reduced gastric acid secretion. Eradication of the bacteria in this subgroup of patients may enhance gastric acid secretion and provoke reflux symptoms. H. pylori organisms do not colonize the specialized intestinal metaplasia characteristic of Barrett's esophagus. H. pylori infection rates in gastric mucosa of patients with Barrett's esophagus occur at a similar or slightly lower frequency than is found in controls. Gastric infection with cagA-positive strains of H. pylori appears to be uncommon in patients with Barrett's esophagus. Furthermore, epidemiologic studies indicate that cagA-positive strains are protective against esophageal adenocarcinoma. Several investigators have proposed that the decreasing prevalence of H. pylori infection might be an important factor in the rising incidence of this tumor.

The phenotype of gastric mucosa coexisting with Barrett's oesophagus

BACKGROUND/AIMS

Barrett's oesophagus complicates the gastro-oesophageal acid reflux. Helicobacter pylori infection, particularly with cagA positive strains, induces inflammatory/atrophic lesions of the gastric mucosa, which may impair acid output. No systematic study has investigated the phenotype of the gastric mucosa coexisting with Barrett's oesophagus. This study was designed to identify the phenotype of gastric mucosa associated with Barrett's oesophagus.

METHODS

In this retrospective case control study, the phenotype of the gastric mucosa was histologically characterised in 53 consecutive patients with Barrett's oesophagus and in 53 (sex and age matched) non-ulcer dyspeptic controls. Both patients and controls underwent extensive sampling of the gastric mucosa (two antral, one incisural, and two oxyntic biopsies). Intestinal metaplasia (IM) was categorised (type I, complete IM; types II and III, incomplete IM) by the high iron diamine stain; cagA status was ascertained by genotyping.

RESULTS

Helicobacter pylori was present in 19 of the 53 patients with Barrett's oesophagus and in 30 of the 53 controls (p < 0.02); eight of the 19 patients with Barrett's oesophagus and 28 of the 35 controls harboured cagA positive H pylori (p < 0.03). The histological severity of non-atrophic gastritis detected in the controls was significantly higher than that detected in the patients with Barrett's oesophagus (p < 0.0001). Multifocal atrophic gastritis was present in 4% of the patients with Barrett's oesophagus and in 23% of controls (p < 0.01). The odds ratio for the association between multifocal atrophic gastritis and Barrett's oesophagus was 0.20 (95% confidence interval, 0.006 to 0.60). Gastric IM was detected in 13.2% of the patients with Barrett's oesophagus and in 30.1% of the controls (p < 0.03). Type III IM at the gastric mucosa was only detected among controls.

CONCLUSIONS

Barrett's oesophagus is associated with a low prevalence of H pylori cagA positive infection and multifocal atrophic gastritis. This pathobiological pattern is considered to be associated with a low risk of distal gastric cancer.

Helicobacter pylori seropositivity and subsite-specific gastric cancer risks in Linxian, China

BACKGROUND

Helicobacter pylori carriage (i.e., persistent exposure to the organism without gastric epithelial cell invasion) is an established risk factor for noncardia gastric cancer. However, its association with the risk of cancer of the gastric cardia is controversial. Consequently, we designed this prospective, nested case-control study to further explore the subsite-specific gastric cancer risks associated with H. pylori seropositivity (a surrogate marker for persistent exposure).

METHODS

A total of 99 patients with gastric cardia cancer, 82 patients with noncardia gastric cancer, and 192 cancer-free subjects were selected from among the participants (n = 29 584) of a nutrition intervention trial previously conducted in Linxian, China. H. pylori seropositivity was determined by assaying for the presence of H. pylori whole cell and CagA antibodies in baseline serum samples from all subjects. Seropositivity was defined as one or both serum assays being positive. Odds ratios (ORs) for subsite-specific gastric cancer were estimated by multivariate logistic regression analyses. All statistical comparisons were two-sided (alpha =.05).

RESULTS

H. pylori seropositivity rates for subjects with gastric cardia cancer, noncardia gastric cancer, and gastric cardia and noncardia cancers combined were 70% (P =.02), 72% (P: =.01), and 71% (P =.003) compared with 56% for cancer-free control subjects. OR estimates for H. pylori seropositivity were 1.87 (95% confidence interval [CI] = 1.10 to 3.17) for gastric cardia cancer, 2.29 (95% CI = 1.26 to 4.14) for noncardia gastric cancer, and 2.04 (95% CI = 1.31 to 3.18) for gastric cardia and noncardia cancers combined.

CONCLUSIONS

H. pylori seropositivity was associated with increased risks for both gastric cardia cancer and noncardia gastric cancer in this well-characterized cohort. Thus, H. pylori carriage may increase the risk of cancer throughout the stomach.

A comprehensive review of the natural history of Helicobacter pylori infection in children

Across populations of children, Helicobacter pylori prevalence ranges from under 10% to over 80%. Low prevalence occurs in the U.S., Canada, and northern and western Europe; high prevalence occurs in India, Africa, Latin America, and eastern Europe. Risk factors include socioeconomic status, household crowding, ethnicity, migration from high prevalence regions, and infection status of family members. H. pylori infection is not associated with specific symptoms in children; however, it is consistently associated with antral gastritis, although its clinical significance is unclear. Duodenal ulcers associated with H. pylori are seldom seen in children under 10 years of age. H. pylori-infected children demonstrate a chronic, macrophagic, and monocytic inflammatory cell infiltrate and a lack of neutrophils, as compared with the response observed in adults. The effect of H. pylori infection on acid secretion in children remains poorly defined. The events that occur during H. pylori colonization in children should be studied more thoroughly and should include urease activity, motility, chemotaxis, adherence, and downregulation of the host response. The importance of virulence determinants described as relevant for disease during H. pylori infection has not been extensively studied in children. Highly sensitive and specific methods for the detection of H. pylori in children are needed, especially in younger pediatric populations in which colonization is in its early phases. Criteria for the use of eradication treatment in H. pylori-infected children need to be established. Multicenter pediatric studies should focus on the identification of risk factors, which can be used as prognostic indicators for the development of gastroduodenal disease later in life.

The gastric cardia in gastro-oesophageal disease

BACKGROUND

There have been conflicting reports concerning the use of cardia biopsies in screening patients for gastro-oesophageal disease.

AIM

To define the histopathological changes in the gastric cardia of patients with and without gastro-oesophageal disease.

METHODS

Topographically mapped gastric biopsy specimens were obtained from patients with gastro-oesophageal disease and from controls. Biopsies were scored on a visual analogue scale of 0 to 5 for Helicobacter pylori, intestinal metaplasia, pancreatic metaplasia, foveolar hyperplasia, and active inflammation. The presence or absence of cardiac glands was recorded.

RESULTS

Sixty-five patients with gastro-oesophageal disease and 71 controls were examined. Intestinal metaplasia was present in cardia biopsies of 10 patients with gastro-oesophageal disease and 11 controls. Only two patients with gastro-oesophageal disease and intestinal metaplasia in the cardia had no evidence of exposure to H pylori. Intestinal metaplasia was not found in the cardia of those with long segment Barrett's oesophagus. Carditis was strongly associated with active H pylori infection (p = 0.000) and resolved after treatment of the infection. A negative association was present between gastro-oesophageal disease and the presence of cardiac glands in cardiac biopsies (p = 0.003). Pancreatic metaplasia was found in 15 of 65 and foveolar hyperplasia in 19 of 65 cases but neither was related to gastro-oesophageal disease.

CONCLUSION

Intestinal metaplasia in the cardia is uncommon in gastro-oesophageal disease in the absence of H pylori infection. With chronic H pylori infection the junction between the cardia and corpus expands in a cardia-corpal direction.

Intestinal metaplasia is the probable common precursor of adenocarcinoma in barrett esophagus and adenocarcinoma of the gastric cardia

BACKGROUND

Intestinal metaplasia in the tubular esophagus is the recognized precancerous lesion of adenocarcinoma in Barrett esophagus. However, it is not yet clear whether adenocarcinoma of the gastric cardia arises from the same premalignant lesion, i.e., intestinal metaplasia of the gastric cardia. The purpose of this study was to compare adenocarcinomas in Barrett esophagus and adenocarcinomas of the gastric cardia at an early stage, when it was more likely that intestinal metaplasia had not been completely overgrown by the tumor.

METHODS

The authors compared the epidemiologic, clinical, and pathologic features of early stage adenocarcinoma in Barrett esophagus and adenocarcinoma of the gastric cardia from 42 patients who underwent resection surgery. The presence of intestinal metaplasia was assessed in the resected specimens by using Alcian blue (pH 2.5) staining.

RESULTS

Intestinal metaplasia was detected in the mucosa adjacent to neoplasia in 25 of 26 patients with adenocarcinoma in Barrett esophagus and in 11 of 16 (69%) patients with adenocarcinoma of the gastric cardia. Patient and tumor characteristics and survival were comparable in both groups.

CONCLUSIONS

Intestinal metaplasia is a very common finding in the mucosa adjacent to early stage adenocarcinoma of the gastric cardia. Adenocarcinoma in Barrett esophagus and adenocarcinoma of the gastric cardia may represent the same disease; the former arises from longer segments of intestinal metaplasia and the latter from intestinal metaplasia of the cardia.

Recent developments in Barrett's esophagus

Barrett's esophagus is a precancerous condition in which the squamous esophageal epithelium is replaced by a columnar epithelium. Although different types of columnar epithelium have been described, the most frequently encountered is specialized columnar epithelium or intestinal metaplasia. Most investigators believe that increased cancer risk is only associated with this type. Esophageal adenocarcinoma is increasing in frequency in the United States and in Western Europe. Recent studies highlight the importance of gastroesophageal reflux disease in esophageal adenocarcinoma. Bile-acid reflux may also play a role. Increasing interest has been expressed in short-segment (2-3 cm) Barrett's esophagus. The contribution of short-segment Barrett's esophagus to cancer at the gastroesophageal junction is currently being studied. Although regular surveillance is often recommended, the commonness of Barrett's esophagus makes such a practice impractical for every patient. Biomarker development is needed to identify patients at greatest risk, with p53 a promising candidate based on recent studies. Initial data suggest that redox mechanisms may be involved in Barrett's esophagus. Several methods have recently been described for reversing Barrett's esophagus to squamous epithelium, but the significance of this practice in terms of reducing cancer risk remains to be demonstrated.

Prevalence of Helicobacter pylori infection in 160 patients with Barrett's oesophagus or Barrett's adenocarcinoma

BACKGROUND

The role of Helicobacter pylori infection in the development of Barrett's oesophagus and its complications is uncertain. The aim of the present study was to determine the importance of H. pylori infection in this disease by comparing the frequency of oesophageal and gastric H. pylori infection in a group of patients with Barrett's oesophagus or adenocarcinoma, with the frequency of infection in a control group without Barrett's disease.

METHODS

The study group included 160 patients (123 male, 37 female; mean age: 61.2 years) who were classified (according to the highest grade pathological lesion in the oesophagus) as having Barrett's intestinal metaplasia (IM; 88 patients), Barrett's oesophagus with low-grade dysplasia (LGD; 28 patients), high-grade dysplasia (HGD; five patients), Barrett's indefinite for dysplasia (n = 4), and Barrett's adenocarcinoma (33 patients). A total of 91 of these patients had gastric antral specimens available for study. The control group consisted of 214 consecutive, prospectively enrolled symptomatic patients (122 male, 92 female; mean age: 57.2 years) who underwent upper gastrointestinal endoscopy and in whom Barrett's oesophagus or Barrett's adenocarcinoma was not found. A modified Warthin-Starry method was used to detect H. pylori infection.

RESULTS

Oesophageal H. pylori infection was found in eight of 160 (5%) patients with Barrett's oesophagus or Barrett's adenocarcinoma. Holicobacter pylori organisms in the oesophagus were found only on non-intestinalized cardiac or oxyntocardiac mucosa. All patients with oesophageal H. pylori infection and an antral biopsy available for study had antral H. pylori infection. Gastric antral H. pylori infection was significantly less prevalent in patients in the Barrett's study group (15/91, 16.5%) than in the non-Barrett's control group (67/214, 31.3%; Fisher's exact test, P = 0.01). Patients from the control group with an endoscopic diagnosis of duodenal ulcer, gastric ulcer, gastritis, or duodenitis had a significantly higher prevalence of infection compared with the Barrett's group, but there was no difference in the infection prevalence in patients in the Barrett's group and patients with reflux oesophagitis, hiatal hernia, no endoscopic abnormality, or any other diagnosis.

CONCLUSIONS

Oesophageal H. pylori infection is uncommon in patients with Barrett's IM, dysplasia, or adenocarcinoma, and may be restricted to non-intestinalized columnar epithelium. Gastric H. pylori infection may have a protective effect for the development of Barrett's oesophagus.