Gastric histology, serological markers and age as predictors of gastric acid secretion in patients infected with Helicobacter pylori

Chronic atrophic gastritis and risk of incident upper gastrointestinal cancers: a systematic review and meta-analysis

BACKGROUND

Previous literature has explored the relationship between chronic atrophic gastritis (CAG) and isolated cancers within the upper gastrointestinal cancers; However, an integrative synthesis across the totality of upper gastrointestinal cancers was conspicuously absent. The research objective was to assess the relationship between CAG and the risk of incident upper gastrointestinal cancers, specifically including gastric cancer, oesophageal cancer, and oesophagogastric junction cancer.

METHODS

Rigorous systematic searches were conducted across three major databases, namely PubMed, Embase and Web of Science, encompassing the timeline from database inception until August 10, 2023. We extracted the necessary odds ratio (OR) and their corresponding 95% confidence interval (CI) for subsequent meta-analysis. Statistical analyses were conducted using Stata 17.0 software.

RESULTS

This meta-analysis included a total of 23 articles encompassing 5858 patients diagnosed with upper gastrointestinal cancers. CAG resulted in a statistically significant 4.12-fold elevated risk of incident gastric cancer (OR = 4.12, 95% CI 3.20-5.30). Likewise, CAG was linked to a 2.08-fold increased risk of incident oesophageal cancer (OR = 2.08, 95%CI 1.60-2.72). Intriguingly, a specific correlation was found between CAG and the risk of incident oesophageal squamous cell carcinoma (OR = 2.29, 95%CI 1.77-2.95), while no significant association was detected for oesophageal adenocarcinoma (OR = 0.62, 95%CI 0.17-2.26). Moreover, CAG was correlated with a 2.77-fold heightened risk of oesophagogastric junction cancer (OR = 2.77, 95%CI 2.21-3.46). Notably, for the same type of upper gastrointestinal cancer, it was observed that diagnosing CAG through histological methods was linked to a 33-77% higher risk of developing cancer compared to diagnosing CAG through serological methods.

CONCLUSION

This meta-analysis indicated a two- to fourfold increased risk of gastric cancer, oesophageal cancer, and oesophagogastric junction cancer in patients with CAG. Importantly, for the same upper gastrointestinal cancer, the risk of incident cancer was higher when CAG was diagnosed histologically compared to serological diagnosis. Further rigorous study designs are required to explore the impact of CAG diagnosed through both diagnostic methods on the risk of upper gastrointestinal cancers.

Pathophysiology of gastro-oesophageal reflux disease: implications for diagnosis and management

Gastro-oesophageal reflux disease (GERD) is a common gastrointestinal disorder in which retrograde flow of gastric content into the oesophagus causes uncomfortable symptoms and/or complications. It has a multifactorial and partially understood pathophysiology. GERD starts in the stomach, where the refluxate material is produced. Following the trajectory of reflux, the failure of the antireflux barrier, primarily the lower oesophageal sphincter and the crural diaphragm, enables the refluxate to reach the oesophageal lumen, triggering oesophageal or extra-oesophageal symptoms. Reflux clearance mechanisms such as primary and secondary peristalsis and the arrival of bicarbonate-rich saliva are critical to prevent mucosal damage. Alterations of the oesophageal mucosal integrity, such as macroscopic oesophagitis or microscopic changes, determine the perception of symptoms. The intensity of the symptoms is affected by peripheral and central neural and psychological mechanisms. In this Review, we describe an updated understanding of the complex and multifactorial pathophysiology of GERD. It is now recognized that different GERD phenotypes have different degrees of reflux, severity of mucosal integrity damage and type, and severity of symptoms. These variations are probably due to the occurrence of a predominant pathophysiological mechanism in each patient. We also describe the main pathophysiological mechanisms of GERD and their implications for personalized diagnosis and management.

Application of serum gastric function markers and digestive tumor indices to the diagnosis of early gastric cancer and precancerous lesions

OBJECTIVES

To study the levels of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 199, CA724, CA242, pepsinogen (PG) I, PGII, gastrin-17 (G-17), the PGI/PGII ratio (PGR), as well as the expression of p27 and Ki67, in patients suffering from early gastric cancer and intraepithelial neoplasia and to provide new markers for the diagnosis of early gastric cancer and precancerous lesions.

METHODS

A retrospective study where the blood serum concentration of CEA, CA199, CA724, CA242, PGI, PGII, G-17 and PGR were tested and also the protein expression of p27 and Ki67 was detected in patients tissues by immunohistochemistry in the Gastrointestinal Endoscopy Center of the Affiliated Hospital of Xuzhou Medical University, Xuzhou, China, from March 2018 to March 2021.

RESULTS

Carbohydrate antigen 242 and CA199 levels in tumor tissue significantly differed among the groups. Pepsinogen I levels decreased with increasing disease severity, G-17 levels increased with the aggravation of severity, and p27 expression decreased with the severity.

CONCLUSION

The combination of serum gastric function markers (PGI and G-17) and p27 digestive tumor indices can serve as markers for the diagnosis of early gastric cancer and intraepithelial neoplasia.

Metabolic alterations in patients with Helicobacter pylori-related gastritis: The H. pylori-gut microbiota-metabolism axis in progression of the chronic inflammation in the gastric mucosa

PURPOSE

To characterize the serum metabolism in patients with Helicobacter pylori-positive and H. pylori-negative gastritis.

METHODS

Clinical data and serum gastric function parameters, PGI (pepsinogen I), PGII, PGR (PGI/II), and G-17 (gastrin-17) of 117 patients with chronic gastritis were collected, including 57 H. pylori positive and 60 H. pylori negative subjects. Twenty cases in each group were randomly selected to collect intestinal mucosa specimens and serum samples. The gut microbiota profiles were generated by 16S rRNA gene sequencing, and the serum metabolites were analyzed by a targeted metabolomics approach based on liquid chromatography-mass spectrometry (LC-MS) technology.

RESULTS

Altered expression of 20 metabolites, including isovaleric acid, was detected in patients with HPAG. Some taxa of Bacteroides, Fusobacterium, and Prevotella in the gut microbiota showed significant correlations with differentially expressed metabolites between H. pylori positive and H. pylori negative individuals. As a result, an H. pylori-gut microbiota-metabolism (HGM) axis was proposed.

CONCLUSION

Helicobacter pylori infection may influence the progression of mucosal diseases and the emergence of other complications in the host by altering the gut microbiota, and thus affecting the host serum metabolism.

Modern Approaches to <i>H. pylori</i> Eradication Therapy in Adults (Literature Review and Resolution of Experts Council)

Aim: to analyze current approaches to H. pylori eradication therapy in adults and present the materials of Experts Council held on December 9, 2022 in Moscow.

General statements. H. pylori infection is the main etiological factor of gastritis, peptic ulcer, and gastric cancer. Eradication of H. pylori is recognized as a necessary measure to reduce the incidence of these diseases. The approaches to selecting an eradication regimen should be optimized to take into account epidemiological trends and achieve better treatment outcomes. The updated Maastricht VI Consensus Report presents the means to overcome the difficulties in selecting an approach to the treatment of H. pylori infection. However, eradication therapy remains challenging due to adverse events (primarily antibiotic-associated diarrhea), poor treatment tolerance and patient compliance. Eradication therapy can be optimized by supplementing treatment regimens with strain-specific probiotics that reduce adverse events, improve patient compliance and eradication rates, such as Saccharomyces boulardii CNCM I-745 strain with established efficacy.

Conclusion. The inclusion of certain probiotics in eradication regimens improves treatment tolerance, reduces the risk of adverse events, improves patient compliance and eradication rates.

Modern Approaches to <i>H. pylori</i> Eradication Therapy in Adults (Literature Review and Resolution of Experts Council)

Aim: to analyze current approaches to H. pylori eradication therapy in adults and present the materials of Experts Council held on December 9, 2022 in Moscow.

General statements. H. pylori infection is the main etiological factor of gastritis, peptic ulcer, and gastric cancer. Eradication of H. pylori is recognized as a necessary measure to reduce the incidence of these diseases. The approaches to selecting an eradication regimen should be optimized to take into account epidemiological trends and achieve better treatment outcomes. The updated Maastricht VI Consensus Report presents the means to overcome the difficulties in selecting an approach to the treatment of H. pylori infection. However, eradication therapy remains challenging due to adverse events (primarily antibiotic-associated diarrhea), poor treatment tolerance and patient compliance. Eradication therapy can be optimized by supplementing treatment regimens with strain-specific probiotics that reduce adverse events, improve patient compliance and eradication rates, such as Saccharomyces boulardii CNCM I-745 strain with established efficacy.

Conclusion. The inclusion of certain probiotics in eradication regimens improves treatment tolerance, reduces the risk of adverse events, improves patient compliance and eradication rates.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

The Synergistic Role of Tip α, Nucleolin and Ras in Helicobacter pylori Infection Regulates the Cell Fate Towards Inflammation or Apoptosis

Infection with Helicobacter pylori (H. pylori) leads to a fork in the road situation where it is critical and complex to judge the fate of the cell. We propose for the first time an in silico representation of a protein level network model that can unfold the mystery behind the cell fate decision between inflammation or cell proliferation or cell death. Upon infection TNF inducible protein α (Tip α) is internalised after binding with the cell surface receptor Nucleolin which is overexpressed on the cell surface thereby activating the Ras pathway. Tip α, Nucleolin and Ras decides the cell fate for apoptosis or abnormal cell proliferation along with ulcers in the gastric tract, hence we term it as the "death triad", which otherwise triggers the inflammatory pathway through downstream signalling of NF-κβ. A series of proteins involved in the signalling cascade are portrayed through compartmentalization of the bacteria and the gut wall. The depicted network works synchronously toward an overarching goal of deciding between apoptosis or inflammation or proliferation. The model has been validated by simulating it with existing transcriptomic data along with clinical findings from patients infected with H. pylori across different regions in India. The results clearly indicate that for a short period of time there is increased binding of Tip α to Nucleolin and the receptor starts to saturate. This increases the tenacity of binding and the cell triggers an inflammatory cascade reaction which involves proinflammatory cytokines such as TNF α thereby progressing to inflammation by activating NF-κβ downstream. On the other hand, Ras involved in interaction with nucleolin can be present both in its activated or inactivated state. Binding of Tip α as a monomer leads to desensitization of Nucleolin leading to cell survival and proliferation.

DIAGNOSTIC ACCURACY OF GASTROPANEL® FOR ATROPHIC GASTRITIS IN BRAZILIAN SUBJECTS AND THE EFFECT OF PROTON PUMP INHIBITORS

BACKGROUND

It has been proposed that the combination of gastrin-17 (G-17), pepsinogens I and II (PGI and PGII), and anti-Helicobacter pylori (H. pylori) antibodies (GastroPanel®, BIOHIT HealthCare, Helsinki, Finland) could serve as biomarkers of atrophic gastritis.

OBJECTIVE

This study aimed to ensure the diagnostic accuracy of GastroPanel® and evaluate the effect of proton pump inhibitors (PPIs) on these biomarkers.

METHODS

Dyspeptic patients who underwent gastrointestinal endoscopy were enrolled in the present study. Histological findings, which were the gold standard to stratify groups, were as follows: no atrophy (controls); antrum atrophy; corpus atrophy; multifocal atrophy; and neoplasia. G-17, PGI, PGII, and anti-H. pylori immunoglobulin (Ig)G antibodies were assayed using commercially available kits. The ratio of PGI/PGII was calculated.

RESULTS

Among 308 patients, 159 (51.6%) were PPI users. The overall prevalence of atrophy was 43.8% (n=135). Ninety-two (29.9%) patients were H. pylori positive according to anti-H. pylori IgG levels. G-17 levels were not low in those with antrum atrophy but were high in those with corpus and multifocal atrophies. PGI levels were significantly lower in those with corpus and multifocal atrophies. The sensitivity of PGI <30 µg/L to detect corpus atrophy was 50% (95% CI 27.8-72.1%), with a specificity of 93.2% (95% CI 84.3-97.5%), a positive likelihood ratio of 7.4 (95% CI 2.9-19.2), and a negative likelihood ratio of 0.5 (95% CI 0.3-0.8). A small number of subjects (n=6) exhibited moderate to intense atrophy (4%), among whom 66.7% exhibited decreased PGI levels. PPI significantly increased the levels of G-17 and PGI, except in those with corpus and multifocal atrophies, in whom PGI levels were not increased by PPIs.

CONCLUSION

GastroPanel® (Gastrin-17, PGI, and PGI/PGII ratio) did not demonstrate high sensitivity for detecting gastric atrophy.

Gastric Peptides-Gastrin and Somatostatin

Gastric acid secretion (i) facilitates digestion of protein as well as absorption of micronutrients and certain medications, (ii) kills ingested microorganisms, including Helicobacter pylori, and (iii) prevents bacterial overgrowth and enteric infection. The principal regulators of acid secretion are the gastric peptides gastrin and somatostatin. Gastrin, the major hormonal stimulant for acid secretion, is synthesized in pyloric mucosal G cells as a 101-amino acid precursor (preprogastrin) that is processed to yield biologically active amidated gastrin-17 and gastrin-34. The C-terminal active site of gastrin (Trp-Met-Asp-Phe-NH₂ ) binds to gastrin/CCK₂ receptors on parietal and, more importantly, histamine-containing enterochromaffin-like (ECL) cells, located in oxyntic mucosa, to induce acid secretion. Histamine diffuses to the neighboring parietal cells where it binds to histamine H₂ -receptors coupled to hydrochloric acid secretion. Gastrin is also a trophic hormone that maintains the integrity of gastric mucosa, induces proliferation of parietal and ECL cells, and is thought to play a role in carcinogenesis. Somatostatin, present in D cells of the gastric pyloric and oxyntic mucosa, is the main inhibitor of acid secretion, particularly during the interdigestive period. Somatostatin exerts a tonic paracrine restraint on gastrin secretion from G cells, histamine secretion from ECL cells, and acid secretion from parietal cells. Removal of this restraint, for example by activation of cholinergic neurons during ingestion of food, initiates and maximizes acid secretion. Knowledge regarding the structure and function of gastrin, somatostatin, and their respective receptors is providing novel avenues to better diagnose and manage acid-peptic disorders and certain cancers. Published 2020. Compr Physiol 10:197-228, 2020.

Assessment of Gastric Acidity by Conventional Endoscopy With Serological Gastric Markers

Background

Gastric acidity could determine Helicobacter pylori (H. pylori)-associated gastritis patterns. In reverse, H. pylori infection could lead disturbance in gastric acid secretion. We attempted to elucidate gastric acid status by conventional endoscopy with pepsinogen test.

Methods

A total of 196 subjects who visited our health promotion center were consecutively enrolled and evaluated by conventional endoscopy, and blood examinations with pepsinogen I, II, and fasting serum gastrin were conducted. As a Japanese study suggested that in H. pylori-positive subjects the cutoff value was PG I/II ratio ≤ 2.7 for hypochlorhydia, PG I/II ratio ≥ 3.3 for hyperchlorhydria. Based on these serological data, we compared conventional endoscopic images with each acid level.

Results

It showed that for hypoacidity, older age, and most of the H. pylori-associated endoscopic appearances featuring mucosal inflammation and more atrophy of corpus or antrum were in favor of hypoacidity in closed type. Mucosal appearances showing severe corpus atrophy and remnant gastritis with advanced background atrophy determine hypoacidity in open type. For hyperacidity, mucosal appearances featuring intact mucosa and less severe atrophy were associated with hyperacid status. Male gender, antrum camouflage were also involved in hyperacidity.

Conclusions

Conventional endoscopy with pepsinogen test could be useful in gastric acid assessment.

Psychological effects of Helicobacter pylori-associated atrophic gastritis in patients under 50 years: A cross-sectional study

BACKGROUND

While gastrointestinal function is known to be closely related to psychological status, the influence of Helicobacter pylori-associated atrophic gastritis is currently unknown. We aimed to determine whether atrophic gastritis status or H. pylori infection is associated with psychological distress or depressed mood.

MATERIALS AND METHODS

We performed a cross-sectional, observational study involving 975 Japanese individuals (503 females; mean age, 44 ± 8 years) who underwent a health checkup. Psychological distress was defined as a Kessler-6 Scale score ≥13 and depressive mood as a Center for Epidemiological Studies Depression Scale score ≥ 16. The odds ratios with 95% confidence intervals assessing the risk of psychological distress or depressive mood associated with H. pylori infection (H. pylori-specific immunoglobulin G levels >10 U/mL) and atrophic gastritis status (pepsinogen I levels < 70 μg/L and pepsinogen I/II ratio < 3) were calculated using multiple logistic analysis adjusting for several covariates.

RESULTS

Individuals with atrophic gastritis had a significantly higher risk of experiencing psychological distress, with younger females (<50 years) displaying the highest risk for psychological distress and depressive mood regardless of H. pylori infection status. Among females aged <50 years, H. pylori-seropositive participants with atrophic gastritis (HP+AG+) showed the highest risk of psychological distress (OR, 16.4; 95% CI, 3.45-94.9) and depression (OR, 2.86; 95% CI, 1.31-6.05), using HP-AG- status as the reference.

CONCLUSIONS

Our findings support the results of previous animal studies regarding the psychological response to gastritis in humans. Further studies are needed to elucidate whether H. pylori eradication provides psychological benefits.

Changes with aging in gastric biomarkers levels and in biochemical factors associated with Helicobacter pylori infection in asymptomatic Chinese population

AIM

To observe changes in gastric biomarker levels with age and effects of Helicobacter pylori (H. pylori) infection in a healthy population, and explore factors associated with gastric biomarkers.

METHODS

Three hundred and ninety-five subjects were selected and underwent physical examinations, biochemical tests, and measurement of serum pepsinogen (PG) I and II, gastrin-17 (G-17) and H. pylori antibody levels. Analyses were made by Student’s t-test, ANOVA, Pearson’s correlation and multiple linear regressions.

RESULTS

PGII levels were higher in the ≥ 65-years-old age group (P < 0.05) and PGI/PGII were lower in the ≥ 75-years-old age group (P = 0.035) compared to the 35-44-years-old age group. Levels of low-density lipoprotein cholesterol (LDL-C) were higher (P = 0.009) in H. pylori-infected subjects that were male. LDL-C levels were higher in 55-74-years-old age group (P < 0.05) for H. pylori-infected subjects and 45-64-years-old age group (P < 0.05) for non-infected subjects compared to 35-44-years-old age group. Hp-IgG level positively correlated with PGI, PGII and G-17 (P < 0.001, P < 0.001, P = 0.006), and negatively correlated with PGI/PGII (P < 0.001). Creatinine positively correlated with PGI, PGII and G-17 (P < 0.001, P < 0.001, P < 0.001). Fasting blood glucose (FBG) positively correlated with PGI/PGII and G-17 (P < 0.001, P = 0.037). Age positively correlated with PGII and G-17 (P = 0.005, P = 0.026).

CONCLUSION

PGII levels increased while PGI/PGII declined with age in a healthy population. H. pylori infection had an effect on raising LDL-C levels to increase the risk of atherosclerosis in males, especially those of elderly age. Age, H. pylori infection, levels of renal function and FBG were associated with levels of pepsinogens and gastrin.

Helicobacter pylori and gut microbiota in multiple sclerosis versus Alzheimer's disease: 10 pitfalls of microbiome studies

Alteration of microbiota has been associated with intestinal, inflammatory, and neurological diseases. Abundance of "good bacteria" such as Bifidobacterium, or their products have been generally believed to be beneficial for any diseases, while "bad bacteria" such as pathogenic Helicobacter pylori are assumed to be always detrimental for hosts. However, this is not the case when we compare and contrast the association of the gut microbiota with two neurological diseases, multiple sclerosis (MS) and Alzheimer's disease (AD). Following H. pylori infection, pro-inflammatory T helper (Th)1 and Th17 immune response are initially induced to eradicate bacteria. However, H. pylori evades the host immune response by inducing Th2 cells and regulatory T cells (Tregs) that produce anti-inflammatory interleukin (IL)-10. Suppression of anti-bacterial Th1/Th17 cells by Tregs may enhance gastric H. pylori propagation, followed by a cascade reaction involving vitamin B₁₂ and folic acid malabsorption, plasma homocysteine elevation, and reactive oxygen species induction. This can damage the blood-brain barrier (BBB), leading to accumulation of amyloid-β in the brain, a hallmark of AD. On the other hand, this suppression of pro-inflammatory Th1/Th17 responses to H. pylori has protective effects on the hosts, since it prevents uncontrolled gastritis as well as suppresses the induction of encephalitogenic Th1/Th17 cells, which can mediate neuroinflammation in MS. The above scenario may explain why chronic H. pylori infection is positively associated with AD, while it is negatively associated with MS. Lastly, we list "10 pitfalls of microbiota studies", which will be useful for evaluating and designing clinical and experimental microbiota studies.

High Serum Pepsinogen I and beta Helicobacter pylori Infection Are Risk Factors for Aspirin-Induced Gastroduodenal Injury

BACKGROUND

Whether gastric hyperchlorhydria and Helicobacter pylori infection contribute to aspirin-induced gastroduodenal injury still lacks evidence. Because serum pepsinogens (PGs) and gastrin-17 (G17) can reflect gastric acid secretion, this study intended to elucidate whether serum PGs, serum G17, and H. pylori infection are associated with aspirin-induced gastrointestinal injury.

SUMMARY

A total of 60 patients taking low-dose aspirin for more than 1 month were enrolled in this study. Serum PG I, PG II, and G17 were determined using ELISA. A 14C-urea breath test was used for the detection of an H. pylori infection. The modified Lanza score was used to evaluate the degree of gastroduodenal injury under endoscopy. The median serum PG I level was significantly higher in the intensive gastroduodenal injury (IGI) group compared to that in the mild gastroduodenal injury group (155.0 vs. 116.6 ng/mL, p = 0.006). The H. pylori infection rate was significantly higher in the IGI group (73 vs. 40%, p = 0.037). Receiver operator characteristic curves analysis revealed that the cutoff value of PG I was 123 ng/mL, with 80% sensitivity and 61.4% specificity. H. pylori infection combined with PG I at >123 ng/mL had an OR (95% CI) of 15.8 (2.4 ± 104.5) for the prediction of aspirin-induced gastroduodenal injury. Key Messages: Serum PG I and H. pylori infection could be used to identify potential high-risk aspirin-induced gastroduodenal injury patients.

A Chronological Increase in Gastric Acid Secretion from 1995 to 2014 in Young Japanese Healthy Volunteers under the Age of 40 Years Old

Gastric acid secretion levels are an important determinant of the manifestation of acid-related upper GI diseases such as gastroesophageal reflux disease. We recently reported that gastric acid secretion levels did not change from the 1990s to 2010s in H. pylori-negative asymptomatic Japanese outpatients with a mean age of 63 years old. However, because young people have a quite different lifestyle, including dietary pattern, from elderly people in Japan, it is worth investigating any chronologic changes in gastric acid secretion in younger generations. The aim of this analysis is to investigate the potential changes in gastric acid secretion from 1995 to 2014 in young Japanese healthy volunteers. Eighty-eight young Japanese healthy volunteers under the age of 40 with a mean age of 26 were extracted from a database accumulated from 1995 to 2014 for the present analysis. Their gastrin-stimulated gastric acid level was determined with the endoscopic gastrin test. In 76 H. pylori-negative subjects, gastric acid secretion levels showed a significant positive correlation with the calendar year when the test was performed (r = 0.27, p < 0.01). A similar trend was observed in 12 H. pylori-positive subjects. A chronological 5-year time period showed a significant positive association with gastric acid secretion in univariate and multivariate analyses (p < 0.01 and p = 0.01, respectively). Gastric acid secretion levels have been increasing in young Japanese healthy volunteers during the last 20 years. We need to monitor future trends in the prevalence of acid-related diseases such as gastro-esophageal reflux disease in Japan.

Imbalance of Gastrointestinal Microbiota in the Pathogenesis of Helicobacter pylori-Associated Diseases

The development of new nucleotide sequencing techniques and advanced bioinformatics tools has opened the field for studying the diversity and complexity of the gastrointestinal microbiome independent of traditional cultural methods. Owing largely to the gastric acid barrier, the human stomach was long thought to be sterile. The discovery of Helicobacter pylori, the gram-negative bacterium that infects upwards of 50% of the global population, has started a major paradigm shift in our understanding of the stomach as an ecologic niche for bacteria. Recent sequencing analysis of gastric microbiota showed that H. pylori was not alone and the interaction of H. pylori with those microorganisms might play a part in H. pylori-associated diseases such as gastric cancer. In this review, we summarize the available literature about the changes of gastrointestinal microbiota after H. pylori infection in humans and animal models, and discuss the possible underlying mechanisms including the alterations of the gastric environment, the secretion of hormones and the degree of inflammatory response. In general, information regarding the composition and function of gastrointestinal microbiome is still in its infancy, future studies are needed to elucidate whether and to what extent H. pylori infection perturbs the established microbiota. It is assumed that clarifying the role of gastrointestinal communities in H. pylori-associated diseases will provide an opportunity for translational application as a biomarker for the risk of serious H. pylori diseases and perhaps identify specific organisms for therapeutic eradication.

Endoscopic gastritis, serum pepsinogen assay, and Helicobacter pylori infection

Endoscopic findings of the background gastric mucosa are important in the Helicobacter pylori-seroprevalent population. It is strongly correlated not only with the risk of gastric cancer, but also with the excretion ability of gastric mucosa cells. In noninfected subjects, common endoscopic findings are regular arrangement of collecting venules, chronic superficial gastritis, and erosive gastritis. In cases of active H. pylori infection, nodularity on the antrum, hemorrhagic spots on the fundus, and thickened gastric folds are common endoscopic findings. The secreting ability of the gastric mucosa cells is usually intact in both noninfected and actively infected stomachs, and the intragastric condition becomes hyperacidic upon inflammation. Increased serum pepsinogen II concentration correlates well with active H. pylori infection, and also indicates an increased risk of diffuse-type gastric cancer. In chronic inactive H. pylori infection, metaplastic gastritis and atrophic gastritis extending from the antrum (closed-type chronic atrophic gastritis) toward the corpus (open-type chronic atrophic gastritis) are common endoscopic findings. The intragastric environment is hypoacidic and the risk of intestinal-type gastric cancer is increased in such conditions. Furthermore, there is a decrease in serum pepsinogen I concentration when the secreting ability of the gastric mucosa cells is damaged. Serologic and endoscopic changes that occur upon H. pylori infection are important findings for estimating the secreting ability of the gastric mucosa cells, and could be applied for the secondary prevention of gastric cancer.

Worldwide Inverse Association between Gastric Cancer and Esophageal Adenocarcinoma Suggesting a Common Environmental Factor Exerting Opposing Effects

OBJECTIVES

The incidence of esophageal adenocarcinoma (EAC) is increasing while adenocarcinoma of the stomach is decreasing. We have investigated whether the incidences of these two cancers and their time trends might be inversely related pointing to a common environmental factor exerting opposite effects on these cancers.

METHODS

For cross-sectional analyses data were abstracted from "Cancer Incidence in Five Continents" (CI5) Volume X and GLOBOCAN 2012. Relevant ICD-10 codes were used to locate esophageal and gastric cancers anatomically, and ICD-O codes for the histological diagnosis of EAC. For longitudinal analyses, age standardized rates (ASRs) of EAC and total gastric cancer (TGC) were extracted from CI5C-Plus.

RESULTS

Estimated (2012) ASRs were available for 51 countries and these showed significant negative correlations between EAC and both TGC (males: correlation coefficient (CC)=-0.38, P=0.006, females: CC=-0.41, P=0.003) and non-cardia gastric cancer rates (males: CC=-0.41, P=0.003 and females: CC=-0.43, P=0.005). Annual incidence trends were analyzed for 38 populations through 1989-2007 and showed significant decreases for TGC in 89% and increases for EAC in 66% of these, with no population showing a fall in the latter. Significant negative correlation between the incidence trends of the two cancers was observed in 27 of the 38 populations over the 19-50 years of available paired data. Super-imposition of the longitudinal and cross-sectional data indicated that populations with a current high incidence of EAC and low incidence of gastric cancer had previously resembled countries with a high incidence of gastric cancer and low incidence of EAC.

CONCLUSIONS

The negative association between gastric cancer and EAC in both current incidences and time trends is consistent with a common environmental factor predisposing to one and protecting from the other.

Association of Hay Fever with the Failure of Helicobacter pylori Primary Eradication

Objective Recently, the number of patients receiving Helicobacter pylori eradication treatment has dramatically increased in Japan, although the eradication rate has gradually decreased. Patient characteristics could affect the eradication rate. Our aim in this study was to investigate the association between failed first-line eradication therapy and hay fever. Methods We researched 356 patients who visited a pharmacy adjacent to the Internal Medicine clinic with a prescription for first-line H. pylori eradication treatment and investigated whether the patients had hay fever using a questionnaire. We separated these patients into 2 groups based on the success or failure of eradication according to the clinical data and performed a logistic regression analysis to investigate the influence of hay fever on first-line eradication failure. Results The eradication rate of patients with and without hay fever was 65.6% and 77.7%, respectively. The adjusted odds ratios according to which patients with hay fever would fail eradication therapy gradually lowered with increasing patient age [≤50 years, odds ratio (OR) 6.81, p=0.089; 51-60 years, OR 2.75, p=0.145; 61-70 years, OR 1.60, p=0.391; >70 years, OR 1.02, p=0.979]. A significant relationship was found for all patients (OR 1.88, p=0.047) and the age group ≤70 years (OR 2.31, p=0.024). Conclusion Patients with hay fever have difficulty with first-line eradication, especially younger patients. The existence of clarithromycin-resistant bacteria is suspected, and other factors may also be involved. When a hay fever sufferer receives first-line treatment, eradication might be difficult and other treatment may be required.

Time series analysis of gastric acid secretion over a 20-year period in normal Japanese men

BACKGROUND

The gastric acid secretion level is an important determinant for the manifestation of the gastroesophageal reflux disease spectrum, finally leading to the development of esophageal adenocarcinoma (EAC). Although the incidence of EAC has remained low in Asia, understanding the recent trend in gastric acid secretion should be helpful in estimating future incidences of EAC in that area. We investigated the latest chronological change (1995-2014) in gastric acid secretion in normal Japanese patients.

METHODS

A total of 307 asymptomatic Japanese men who attended the clinic for annual endoscopic checkups from 1995 to 2014 were enrolled in this analysis. Gastrin-stimulated gastric acid secretion was estimated with the endoscopic gastrin test. The association between gastric acid secretion and chronological period was assessed with a multivariate linear regression analysis.

RESULTS

Overall gastric acid secretion gradually increased over the 20-year period in the entire cohort in the unadjusted analysis (p < 0.05). However, the apparent increase was largely related to the relative decreasing rate of H. pylori infection, which profoundly inhibited gastric acid secretion. Gastric acid secretion did not change over the 20-year period in H. pylori-negative subjects, and it showed only a mild increase during this period in H. pylori-positive subjects.

CONCLUSIONS

Considering that gastric acid secretion remained unchanged in H. pylori-negative Japanese men over a 20-year period at a level much lower than that in Occidental subjects, upper gastrointestinal disease profiles in the Japanese population will differ from those in Western countries in the post-H. pylori era.

No increase in gastric acid secretion in healthy Japanese over the past two decades

BACKGROUND

The prevalence of gastroesophageal reflux disease (GERD) has been increasing worldwide over recent decades. A previous study demonstrated that gastric acid secretion, thought to be an important factor in the increase in the rate of GERD, in Japanese individuals increased in the era from the 1970s to the 1990s. The aim of this study was to evaluate whether gastric acid secretion has altered over the past two decades with and without the influence of Helicobacter pylori infection in nonelderly and elderly Japanese.

METHODS

Gastric acid secretion, the concentrations of serum gastrin, pepsinogen I, and pepsinogen II, and H. pylori infection were determined in 78 healthy Japanese subjects. The findings were compared with data obtained in the 1990s.

RESULTS

Basal acid output (BAO) and maximal acid output (MAO) gradually decreased with age in H. pylori-negative subjects. In addition, those with H. pylori infection tended to show decreased gastric acid secretion as compared with those without infection, particularly in the elderly group. MAO decreased gradually with age in males, whereas it remained unchanged with age in females. MAO in H. pylori-negative subjects has not changed over the past two decades (17.7 mEq/h vs 17.6 mEq/h in nonelderly subjects, and 15.2 mEq/h vs 12.7 mEq/h in elderly subjects).

CONCLUSIONS

In contrast to the increased prevalence of GERD, gastric acid secretion has not increased over the past two decades in Japanese. However, secretion has decreased with age in males but not in females, which may partly explain the sex difference in the age-related GERD prevalence.

Endoscopic findings for predicting gastric acid secretion status

BACKGROUND AND AIM

Gastric acidic abnormalities are related to various types of diseases in Helicobacter pylori (H. pylori) infection status. However, no studies have shown correlations between many tiny endoscopic findings and the acid secretion level simultaneously. In the present study, we investigated predictive tiny endoscopic findings of hyperchlorhydria and hypochlorhydria.

METHODS

A total of 223 subjects without organic diseases who underwent esophagogastroduodenoscopy and endoscopic gastrin test (EGT) for estimating gastrin-stimulated gastric acid secretory response between 1999 and 2012 at our institution were retrospectively analyzed. Two blinded expert endoscopists reviewed the images independently and recorded the endoscopic findings.

RESULTS

According to the EGT values, the enrolled subjects were categorized into hyperchlorhydria, normal acid secretion, and hypochlorhydria groups. In all subjects, hematin (odds ratio [95% confidence interval] = 3.32 [1.40-7.84]) and antral erosion(2.88 [1.24-6.70]) were the predictive endoscopic findings for hyperchlorhydria, and swelling of areae gastricae (14.4 [5.74-36.1]) and open-type atrophy (15.1 [7.35-31.1]) were those for hypochlorhydria. In addition, the predictive endoscopic findings for hyperchlorhydria differed according to the H. pylori infection status, hematin in H. pylori-positive subjects and antral erosion in H. pylori-negative subjects, in contrast to those for hypochlorhydria, which were the same irrespective of the H. pylori infection status.

CONCLUSIONS

We could predict the acid secretion status based on the endoscopic findings regardless of H. pylori infection status, which would be of some help for evaluating the risk for acid-related diseases.

Helicobacter pylori-Mediated Protection against Extra-Gastric Immune and Inflammatory Disorders: The Evidence and Controversies

A large number of studies link H. pylori infection with a reduced risk of developing extra-gastric conditions such as allergy, asthma, inflammatory bowel disease, coeliac disease and multiple sclerosis. The strength of the evidence for these protective associations is quite variable, and published studies often do not agree. This review article discusses some of the reasons for these discrepancies, and the difficulties faced when designing studies. Examples of some protective disease associations are described in detail, where the evidence is most abundant and thought to be more reliable. The most convincing of these are supported by published mechanistic data, for example with animal models, or incidence of disease exacerbation in humans following H. pylori eradication. Although controversial, this field is very important as the prevalence of H. pylori is decreasing throughout the world whilst many chronic diseases are becoming more common. These trends are likely to continue in the future, therefore it is important that we fully understand if and how H. pylori confers protection.

Identification of a high-risk group for low-dose aspirin-induced gastropathy by measuring serum pepsinogen in H. pylori-infected subjects

BACKGROUND

We recently demonstrated in humans that the extent of low-dose aspirin (LDA)-induced gastropathy was directly related to the individual gastric acid secretion level. We also established reliable cutoff serum pepsinogen (PG) values to predict gastric acid secretion status. In this study, we investigated the clinical usefulness of measuring the serum pepsinogen values for identifying a high-risk group for gastric mucosal injury among chronic LDA users.

METHODS

One hundred long-term LDA users were enrolled in this analysis. Serum from each subject was subjected to determination of H. pylori status and measurement of pepsinogen values. According to our recent report, a PG I value ≥ 50 ng/mL was defined as estimated hyperchlorhydria in H. pylori-negative subjects, while a PG I/II ≥ 3.3 was defined as estimated hyperchlorhydria in H. pylori-positive subjects. The grade of gastric mucosal injury was assessed endoscopically, and multiple logistic regression analyses were used to estimate the risk.

RESULTS

Estimated hyperchlorhydria was a strong independent risk for intensive gastric mucosal injury with an OR (95% CI): 34.0 (4.5-259) and for gastric ulcer with an OR (95% CI): 10.2 (1.8-58.3) in H. pylori-positive subjects, while it was not a significant risk in H. pylori-negative subjects. The association persisted even after excluding those with conventional risks for LDA-gastropathy such as ulcer histories.

CONCLUSION

Using simple serum measurement of H. pylori antibody and pepsinogen concentrations, an extremely high-risk group for LDA-induced gastropathy could be extracted, and these patients should become a therapeutic target for prevention of LDA-induced gastropathy.

Cutoff serum pepsinogen values for predicting gastric acid secretion status

Measurement of the gastric acid secretion is useful for estimating the risk for various diseases in the upper gastro-intestinal tract; however, the procedure causes significant distress to the subjects. Pepsinogens I and II are secreted from the gastric fundic glands, and thus, the serum pepsinogen levels reflect the gastric functional statuses. The aim of this study is to establish appropriate serum pepsinogen cutoff points for predicting the gastric acid secretion status. In a total of 627 Japanese subjects, gastric acid secretion was measured with an endoscopic gastrin test, and the serum pepsinogen values and serum Helicobacter (H.) pylori-IgG antibody were also measured. After checking the correlation between gastric acid secretion and serum pepsinogen, the receiver operating characteristics analyses were employed for determining the most suitable cutoff points of serum pepsinogen for the gastric acid secretion status (i.e., hypochlorhydria, profound hypochlorhydria, and hyperchlorhydria). The pepsinogen I/II ratio and pepsinogen I showed the best correlation with gastric acid secretion in H. pylori-positive and H. pylori-negative subjects, respectively. The serum pepsinogen I/II ratio (or pepsinogen I in cases of H. pylori-negative subjects) was useful to determine the gastric acid secretion status with acceptable to outstanding diagnostic accuracy (the range of the area under the curve: 0.79-0.93). The diagnostic accuracy was further improved after stratifying the subjects by H. pylori-infection status. Estimating gastric acid secretion levels by simple measurement of serum pepsinogens will have significant clinical implications in estimating the risks for various diseases of the upper gastrointestinal tract.

A comprehensive evaluation of fasting serum gastrin-17 as a predictor of diseased stomach in Chinese population

BACKGROUND AND AIM

Fasting serum gastrin-17 (FsG17) is considered as a noninvasive biomarker reflecting the structure and functional status of gastric mucosa, but its clinical utility remains unclear. This study aimed to evaluate FsG17 comprehensively: establish the ranges and cut-off points of FsG17 levels in different gastric diseases, identify their influencing factors, and investigate the accuracy of FsG17 for identifying diseased stomach.

METHODS

The study included 4064 participants from Northern China between 2008 and 2013. FsG17 and serum Helicobacter pylori IgG antibody levels were measured by enzyme-linked immunosorbent assay. Diagnostic accuracy was assessed by receiver operator characteristic curves. Multivariate logistic regression analysis was performed to determine the best predictors of gastric histopathological conditions.

RESULTS

Median FsG17 levels in healthy, non-atrophic, atrophic, and cancerous stomachs were 1.8, 4.0, 3.8, and 6.1 pmol/l, respectively. Age, smoking status, alcohol consumption, H. pylori infection, and predominant lesion site were factors that affected FsG17 levels. The optimal cut-off values for FsG17 were 3.0 pmol/l (sensitivity of 59.3% and specificity of 67.3%) for discriminating between healthy stomach and diseased stomach and 10.7 pmol/l (sensitivity of 37% and specificity of 83.7%) for discriminating between cancerous stomach and cancer-free stomach; the screening accuracy was higher (sensitivity of 50.0% and specificity of 83.0%) for gastric cancer in the corpus. Multivariate analysis showed that FsG17, gender, age, and H. pylori infection were independent predictors of cancerous stomach.

CONCLUSION

With the progression from health stomach to malignancy, FsG17 levels significantly increased and were influenced by other factors. FsG17 combined with age, gender, and H. pylori infection could distinguish between cancerous stomach and cancer-free stomach. The results will enhance our understanding of the potential clinical utility of FsG17.

Interaction between Helicobacter pylori infection, nonsteroidal anti-inflammatory drugs and/or low-dose aspirin use: Old question new insights

Previous reports clearly demonstrated that Helicobacter pylori (H. pylori) infection, nonsteroidal anti-inflammatory drugs (NSAID) or low dose aspirin (ASA) use significantly and independently increased the risk for the development of peptic ulcer disease. Today, the presence of H. pylori infection associated with low dose ASA and/or NSAID use in the same patient is becoming more frequent and therefore the potential interaction between these factors and the consequences of it has important implications. Whether NSAID intake in the presence of H. pylori infection may further increase the risk of peptic ulcer carried by the presence of only one risk factor is still a matter of debate. Studies on the interaction between the two risk factors yielded conflicting data and no consensus has been reached in the last years. In addition, the interaction between H. pylori infection and low-dose ASA remains even more controversial. In real clinical practice, we can find different clinical scenarios involving these three factors associated with the presence of different gastrointestinal and cardiovascular risk factors. These huge variety of possible combinations greatly hinder the decision making process of physicians.

Lifestyle and gastric function

The stomach has a range of functions, including chemical digestion and mechanical breakdown of food, temporary storage of bulk intake, and regulation of the passage of nutrients into the duodenum. Further gastric functions are the nonspecific defense against microbes entering the gastrointestinal tract, preparation of ions as well as liberation of protein-bound cobalamin and production of intrinsic factor for uptake further along the tract, and finally limited absorption of water, alcohol, and some fat-soluble food components including some drugs. These functions are influenced by various lifestyle factors, such as smoking and alcohol intake with interference by Helicobacter pylori colonization. This paper focuses on the interaction between lifestyle and gastric function.

Helicobacter pylori infection affects immune responses following vaccination of typhoid-naive U.S. adults with attenuated Salmonella typhi oral vaccine CVD 908-htrA

BACKGROUND

 We examined the association between Helicobacter pylori infection and the immune response following oral immunization of US adults with attenuated Salmonella Typhi vaccine CVD 908-htrA.

METHODS

 Baseline sera from 74 volunteers without a history of typhoid fever who were immunized orally with CVD 908-htrA were tested by enzyme-linked immunosorbent assay for immunoglobin G (IgG) antibodies to H. pylori, hepatitis A antibodies (a marker of low socioeconomic status and exposure to enteric infections), and pepsinogen (PG) I and II levels (measures of gastric inflammation). IgG against S. Typhi lipopolysaccharide (LPS) O and flagella was measured before and 28 days following immunization; a ≥4-fold increase in titer from baseline constituted seroconversion.

RESULTS

 Seroconversion of S. Typhi IgG LPS antibodies was significantly higher among vaccinees infected with H. pylori versus uninfected subjects: adjusted odds ratio (OR) 3.8, 95% confidence interval (CI), 1.1-12.6 (P = .03). A low PG I:PG II ratio (<5), indicating more advanced corpus gastritis, increased the odds of seroconversion of IgG S. Typhi flagella antibody (adjusted OR 6.4, 95% CI, 1.3-31.4; P = .02). Hepatitis A infection did not influence the immune response to CVD 908-htrA.

CONCLUSIONS

 H. pylori infection and gastric inflammation may enhance humoral immunity to oral attenuated S. Typhi vaccine.

Serum ghrelin; a new surrogate marker of gastric mucosal alterations in upper gastrointestinal carcinogenesis

Background

A few studies have indicated inverse relationships between serum ghrelin and gastric and esophageal cancers but those associations have been restricted to specific populations, including smokers and overweight individuals. We examined the association between ghrelin and gastroesophageal cancers and atrophic gastritis in a population-based setting.

Methods

In total 220 gastroesophageal cancers, comprising non-cardia and cardia gastric cancer, esophageal adenocarcinoma, esophageal squamous cell carcinoma (SCC) and age and gender-matched controls were recruited. Serum ghrelin, pepsinogen I/II ratio (PGI/II) and anti-H.pylori IgG antibodies were measured. Relationships between ghrelin and gastroesophageal cancers, after adjustment for PGI/II ratio, H.pylori status and smoking, were tested using logistic regression. Furthermore, in 125 endoscopically normal volunteers, with and without histological atrophic gastritis, the relationship with ghrelin was compared.

Results

Serum ghrelin (lowest vs. highest quintile) was inversely associated with gastric cancer: OR (95% CI) 8.71 (1.70–44.59) for cardia and 6.58 (1.26–34.46) for non-cardia cancer. Lower serum ghrelin was also associated with esophageal SCC: OR (95% CI) 5.69 (1.36–23.78), but not with esophageal adenocarcinoma. A similar association was observed between gastric cancer (cardia and non-cardia) and esophageal SCC when serum ghrelin was analysed as a continuous scaled variable. In endoscopically-normal volunteers, extensive atrophic gastritis was associated with low serum ghrelin [OR (95% CI) 0.25 (0.10–0.64)].

Conclusion

Inverse associations between ghrelin and some gastroesophageal cancers suggest a potential role for serum ghrelin as a biomarker of upper gastrointestinal cancers and atrophic gastritis. In areas with a high incidence of gastric and/or esophageal cancer, screening might be more effectively targeted to individuals with low serum ghrelin in addition to the PGI/II ratio.

Barrett's esophagus: prevalence-incidence and etiology-origins

Although the prevalence of Barrett's esophagus (BE) is rising no data exist for racial minorities on prevalence in the general population. Minorities have a lower prevalence than Caucasians, and yet age, smoking, abdominal obesity, and Helicobacter pylori are all risk factors. Metabolic changes induced by adipocytokines and the apparently strong association between obesity, central adiposity, and BE may lead to reconsideration of some aspects of the natural history of BE. There is lack of experimental evidence on acid sensitivity and BE, which is hyposensitive compared to esophageal reflux disease. Reactive nitrogen and oxygen species lead to impaired expression of tumor suppressor genes, which can lead to cancer development; thus, antioxidants may be protective. Gastroesophageal reflux disease may be considered an immune-mediated disease starting at the submucosal layer; the cytokine profile of the mucosal immune response may explain the different outcome of gastroesophageal reflux.

The prevalence and incidence of Helicobacter pylori-associated peptic ulcer disease and upper gastrointestinal bleeding throughout the world

Due to heightened awareness regarding testing for and eradication of infection, the prevalence and incidence of H pylori infection (and by extension the prevalence and incidence of peptic ulcer disease) appear to have declined in recent years. However, antimicrobial resistance is mounting and traditional clarithromycin- or metronidazole-containing triple therapies may no longer be highly effective at eradicating the infection. Combined bismuth- and metronidazole-containing quadruple therapy or sequential 4-drug therapy may be better choices for first-line treatment against this unique pathogen that is ideally suited to survive in the human stomach.

Pepsinogen I and II, Gastrin and Cag A Serum Levels in Shiraz

BACKGROUND Despite the similar rate of HP infection, the rate of gastric cancer (GC) differs in different regions of the country. There are conflicting reports for using a panel of serologic tests such as pepsinogens I, II (PG I and PG II), and gastrin for population screening. We designed this study to assess healthy appearing adults in Shiraz, southern Iran in order to evaluate the correlation of these serological tests with demographics and lifestyle in a region with a low rate of gastric malignancy. METHODS In a population-based study, 846 out of 1978 subjects who were selected by cluster random sampling based on postal code division in Shiraz agreed to participate in the present study. A questionnaire that included age, gender, weight and height, lifestyle such as physical activity, smoking and the use of nonsteroidal anti inflammatory drugs (NSAIDs) was completed. A blood sample was taken after overnight fasting for measurements of PG I, PG II and Cag A status by enzyme-linked immunosorbant assay (ELISA). Gastrin level was measured by radioimmunoassay (RIA). RESULTS The study included 305 men and 541 women. Their mean age was 50.53+11.4 (range: 35-99 years). The level of PG I was significantly more in males than females (116.6±57.1 vs. 103.1±55.8, p < 0.001), lower in older age groups (p = 0.01), and rural compared with urban residents (110.3+55.7 vs. 100.2+58.1, p = 0.02). The serum level of PG II was less in obese subjects (p = 0.5). There was no significant correlation between PG I, PG II, smoking, NSAID use and activity. Gastrin level were not correlated with any of the demographic characteristics. The level of Cag A was significantly different between males and females (30.5±37 vs. 37.7±41.7, p < 0.001), more in older subjects (p = 0.007) and non smokers (p = 0.001). The serum levels of PG I and PG I/PG II ratio decreased significantly in subjects with positive Cag A serology (p < 0.05). The ratio of PG I/PG II was lower than 3 in 35 (4.1%) subjects. CONCLUSION In this area, the PG I/PG II ratio is less than 3 in 4% of subjects of which most are positive for Cag A serology and older than 50. We recommend comparison of these findings with high GC mortality regions.

High prevalence of duodenal ulcer in a tertiary care hospital in the city of São Paulo, SP, Brazil

CONTEXT: In spite of Helicobacter pylori infection being the etiological cause of peptic ulcer and its high prevalence in Brazil, the prevalence of peptic ulcer disease has been poorly studied. OBJECTIVES: To verify the peptic ulcer disease prevalence in patients of a tertiary care hospital. METHODS: Diagnostic findings from 1,478 consecutive endoscopies were correlated with the urease test results for H. pylori infection diagnosis and demographic data in a total of 3,779 endoscopies performed in 2005. The mean age of the patients was 51.14 ± 16.46, being 613 (41.5%) men. RESULTS: Peptic ulcer was diagnosed in 494 (33.4%) patients with a mean age of 54.86 ± 14.53, 205 (52%) were men, being 391 (26.5%) duodenal ulcer and 103 (7%) gastric ulcer. Normal endoscopy was found in 272 (18.4%) patients with a mean age of 38.4 ± 15.22, being 49 (18%) men. The comparison of peptic ulcer group with the patients that had normal endoscopy revealed that H. pylori infection [P = 0.005; OR = 1.70; 95% CI = 1.17-2.47][ign], male gender [P<0.0001; OR = 5.53; 95%CI = 3.67-8.34][ign] and older age [P<0.0001; OR = 1.08; 95%CI = 1.06-1.09] increased the risk of peptic ulcers. The overall H. pylori prevalence was 53% (786). CONCLUSIONS: Prevalence of duodenal ulcer is high in a Brazilian population that had H. pylori infection associated with older age and male gender as important determinants to gastrointestinal diseases outcome. Future prospective studies should confirm these findings.

Low serum levels of pepsinogen and gastrin 17 are predictive of extensive gastric atrophy with high-risk of early gastric cancer

Atrophic gastritis (AG) is a well-recognized high-risk condition for developing gastric cancer (GC). Gastrin 17 (G17), a hormone secreted from antral G cells, regulates gastric acid secretion, and its serum level is a possible indicator of antral atrophy. Serum pepsinogen is well established as the indicator of AG involving the corpus. Here we investigated whether serum PG and G17 levels would be useful for determining the topographic pattern of AG and estimating the risk of GC. Enrolled were 122 Japanese patients with early GC (114 well- to moderate-differentiated cancers and 8 poorly-differentiated cancers). In addition, 178 subjects without GC were recruited as control from those undergoing endoscopic examination (non-GC group). All subjects were histologically assigned to the following four groups: non-AG, antrum-predominant AG, corpus-predominant AG, and multifocal AG, affecting the antrum and corpus. Serum concentrations of pepsinogen and G17 were determined using ELISA. Multifocal AG was more frequent in the GC group than in the adjusted non-GC group, and had the highest risk of GC (OR 25.1). Serum G17 was significantly decreased with the exacerbation of antral atrophy in the coexistence of corpus atrophy. Serum biomarker profiles showed that the low levels of pepsinogen and G17 could discriminate between multifocal AG and other types of AG, but not with pepsinogen level alone. Serologically defined multifocal AG had the highest cancer risk among other serologically defined AG groups (OR 26.9). In conclusion, the low serum levels of pepsinogen and G17 are predictive of extensive gastric atrophy with high-risk of early GC.

Serum level of pepsinogen significantly associated with gastric distress induced by amino-bisphosphonates

To elucidate whether serum levels of pepsinogens are associated with the occurrence of gastrointestinal adverse events induced by amino-bisphosphonates (amino-BP), the serum levels of pepsinogen were measured in amino-BP users. Our results indicate that measurement of pepsinogen I is useful in predicting gastric distress induced by amino-BP in osteoporosis.

INTRODUCTION

To elucidate whether serum levels of pepsinogens are associated with the occurrence of gastrointestinal adverse events induced by amino-BP, the serum levels of pepsinogen I and II were measured in amino-BP users.

METHODS

When the patients complained of gastric distress symptoms during the first 6 months after amino-BP use resulting in discontinuation of the drug, endoscopical examinations were performed to assess whether gastric lesions were present. A total of 223 amino-BP users were enrolled in the study, of which 47 patients refused to take the drug due to gastric distress symptoms. The remaining 176 patients did not complain of any gastric distress.

RESULTS

Among 47 patients, eight patients showed obvious gastric lesions such as gastric or duodenal ulcers and acute gastric mucosal lesions in the endoscopical examination. The remaining 39 patients did not show any gastric lesions. The possible confounding factors, such as a Helicobactor pylori infection or concurrent use of ulcerogenic agents, did cause not affect gastric distress in amino-BP users. The serum pepsinogen I level was significantly associated with severity of the gastric lesion 46.8 ± 27.7, 60.8 ± 32.4, and 103.4 ± 49.2 ng/ml for patients without any gastric distress, with gastric distress accompanied no gastric lesions, and with gastric distress accompanied gastric lesions, respectively.

CONCLUSIONS

ROC analysis revealed that the cutoff value of pepsinogen I for expectation of gastric regions was 76.8 ng/ml. The results clearly indicate that measurement of pepsinogen I may be useful in predicting gastric distress induced by amino-BP in osteoporosis.

Anti-acid medication as a risk factor for food allergy

An important feature for oral allergens is their digestion-resistance during gastrointestinal transit. For some oral allergens, digestion stability is an innate feature, whereas digestion-labile antigens may only persist in times of impairment of the digestive system. In this review, we collect evidence from mouse and human studies that besides the inherent molecular characteristics of a food protein, the stomach function is decisive for the allergenic potential. Gastric acid levels determine the activation of gastric pepsin and also the release of pancreatic enzymes. When anti-ulcer drugs inhibit or neutralize gastric acid, they allow persistence of intact food allergens and protein-bound oral drugs with enhanced capacity to sensitize and elicit allergic reactions via the oral route. Mouse studies further suggest that maternal food allergy arising from co-application of a food protein with anti-acid drugs results in a Th2-biased immune response in the offspring. Especially, anti-ulcer drugs containing aluminum compounds act as Th2 adjuvants. Proton pump inhibitors act on proton secretion but also on expression of the morphogen Sonic hedgehog, which has been related to the development of atrophic gastritis. On the other hand, atrophic gastritis and resulting hypoacidity have previously been correlated with enhanced sensitization risk to food allergens in elderly patients. In summary, impairment of gastric function is a documented risk factor for sensitization against oral proteins and drugs.

Patients with Helicobacter pylori infection have less severe gastroesophageal reflux disease: a study using endoscopy, 24-hour gastric and esophageal pH metry

BACKGROUND AND AIM

The relationship between gastroesophageal reflux disease (GERD) and Helicobacter pylori is controversial. We evaluated endoscopic, 24-h gastric and esophageal acid profile among patients with GERD in relation to H. pylori, as the latter might alter gastric acid secretion.

METHODS

Patients with GERD (n = 123), who were not on acid-suppressive drugs, and had not received anti-H. pylori therapy, underwent gastroduodenoscopy and tests for H. pylori detection. Esophageal manometry, 24-h pH metry, serum pepsinogen-I (PG-I), PG-II and gastrin-17 ELISA were done in all these patients. Univariate and multivariate analyses were performed to assess independent predictors for erosive esophagitis (EE).

RESULTS

Of 123 patients (mean age 40.5 [13.1] years, 85 [69.1%] men), 59 (47.9%) had H. pylori infection. EE was more common in H. pylori non-infected than infected (49 vs. 32, p < 0.001). Among patients older than 40 years, absence of H. pylori was associated with lower esophageal pH and longer reflux (p = 0.02 and p < 0.001, respectively). PG-I/PG-II ratio was lower in H. pylori infected subjects (p < 0.001). In patients with higher LA grade of esophagitis, elevated PG-I levels and PG-I/PG-II ratio were associated with more acidic stomach (p = 0.04 and p = 0.01, respectively). Multivariate analyses showed low gastrin-17 (p = 0.016), higher age (p = 0.013), hiatus hernia (p = 0.004) and absence of H. pylori (p = 0.03) were independent predictors for risk of EE.

CONCLUSION

H. pylori infection is associated with less acidic stomach and less severe GERD. Low gastrin-17, higher age, hiatus hernia and absence of H. pylori were the best predictors for EE risk.

Prevalence of atrophic gastritis in dyspeptic patients in Piedmont. A survey using the GastroPanel test

BACKGROUND

Chronic atrophic gastritis (CAG) is a precursor of the intestinal type of gastric cancer, the second leading cause of cancer-related death worldwide. GastroPanel is a recently marketed serological kit for the non-invasive diagnosis of CAG, defined by some authors "even more reliable than biopsy histology". The goal of this study was 1) to evaluate the agreement between the serum gastric profile provided by GastroPanel (PGI, PGII, G-17, AbHp) and histology over CAG diagnosis, and 2) to evaluate the prevalence of CAG by means of GastroPanel in a Northern Italian dyspeptic population.

METHODS

Basal blood samples for GastroPanel parameters evaluation (Biohit Plc, Finland) were collected after an overnight fast from 1387 dyspeptic patients (age range: 18-80 years; F 704). Gastroscopy with two biopsies each of the antrum and corpus was offered to a group of the first 400 consecutive patients (age 18-80 years, F 214) to compare the results of histology and GastroPanel in CAG.

RESULTS

Agreement between GastroPanel and histology for corpus-prevalent CAG was 94%, with a sensitivity and specificity of 80% and 96%, respectively. In our series of 1387 dyspeptic patients, the prevalence of corpus-prevalent CAG, of antral-prevalent CAG and of multifocal CAG (antrum+ corpus) was 10.7%, 3.6% and 2.4%, respectively. Out of the 34 patients with multifocal atrophic gastritis, 12% were under 30 years of age.

CONCLUSIONS

GastroPanel is a reliable non-invasive test for diagnosis of CAG and deserves consideration for current use in clinical practice as a valuable diagnostic tool.

Helicobacter pylori immunoproteomics in gastric cancer and gastritis of the carcinoma phenotype

Helicobacter pylori infection is linked to the development of gastric cancer. Atrophic body gastritis is considered the first important step in the histogenesis of such neoplasia. H. pylori infection is involved in the induction of atrophic body gastritis, but documentation of H. pylori infection is difficult because of the progressive disappearance of the bacterium. Host-pathogen interactions may be investigated by means of immunoproteomics, which provides global information regarding the host humoral response to H. pylori infection and allows the identification of relevant specific and nonspecific antigens, and can be used for diagnostic or prognostic purposes. In the present review, we describe how several research groups used H. pylori immunoproteomics to investigate highly immunoreactive bacterial antigens related to the development of gastric cancer.

High efficacy of bismuth subcitrate for Helicobacter pylori eradication in pangastritis

BACKGROUND

The influence of gastritis patterns in Helicobacter pylori eradication rates has been poorly investigated.

AIMS

To compare the efficacy of bismuth or proton pump inhibitors triple therapy for H. pylori eradication in pangastritis.

PATIENTS AND METHODS

One hundred and eight patients with pangastritis were assigned to either lansoprazole 30 mg once a day (n=54) or bismuth 240 mg bis in die (n=54) for 14 days combined, for the first week, with amoxicillin 1g plus metronidazole 250 mg tris in die. Eradication was confirmed by (13)C-urea breath test.

RESULTS

With bismuth, successful eradication was observed in 75.9% (41/54) in the intention-to-treat analysis and 78.8% (41/52) in the per-protocol analysis. With lansoprazole, the eradication rates were respectively 46.3% (25/54) and 51.0% (25/49). Bismuth had a significant higher efficacy according to both intention-to-treat analysis (p=0.0029) and per-protocol analysis (p=0.0038) with OR of 3.66 (95% CI: 1.61-8.32) and 3.58 (95% CI: 1.50-8.54) respectively. At regression analysis, the only independent variable affecting eradication was the type of regimen (p=0.026) with an OR of 3.31 (95% CI: 1.16-9.44).

CONCLUSIONS

In pangastritis patients, bismuth is more effective than PPI in first-line eradication. For improving the overall eradication rates, an evaluation of gastritis extent might need to be considered.

Serum pepsinogens and risk of esophageal squamous dysplasia

Pepsinogens are a class of endopeptidases that are secreted by the gastric epithelium and released into the circulation. Low serum pepsinogen I (PGI) and low serum pepsinogen I/pepsinogen II ratio (PGI/II ratio) are markers of gastric fundic atrophy, and have recently been shown to be associated with increased risk of esophageal squamous cell carcinoma (ESCC). We conducted the current study to test whether these markers are also associated with esophageal squamous dysplasia (ESD), the precursor lesion of ESCC. We measured serum PGI and PGII, using enzyme-linked immunosorbent assays, in 125 case subjects (patients with moderate or severe ESD) and 250 sex-matched control subjects (no ESD) selected from an endoscopic screening study in Linxian, China. We used conditional logistic regression models adjusted for age, smoking and place of residence to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). Serum PGI showed no statistically significant association with ESD, whether analyzed as a dichotomous, ordinal (quartiles) or continuous variable. Lower serum PGI/II ratio, however, showed a dose-response association with increased risk of ESD, with an adjusted OR (95% CI) of 2.12 (1.08-4.18), comparing the lowest versus the highest quartile. The association between the lower serum PGI/II ratio and log OR of ESD was nearly linear, and the p-value for the continuous association was 0.03. Lower serum PGI/II ratio was linearly associated with higher risk of ESD. This result is consistent with recent findings that gastric atrophy may increase the risk of ESCC.

Barrett's esophagus is characterized by the absence of Helicobacter pylori infection and high levels of serum pepsinogen I concentration in Japan

BACKGROUND AND AIM

It has been reported that patients with Barrett's esophagus (BE) may have gastric acid hypersecretion. Serological markers such as serum pepsinogen or gastrin have been used to estimate the gastric secretory function. The aim of this study was to compare the serum pepsinogen and gastrin concentrations in view of Helicobacter pylori infection status between BE patients and the controls.

METHODS

Thirty-six patients with long-segment BE were enrolled in this study. Three age- and sex-matched controls were assigned to each patient. Serum pepsinogen and gastrin concentrations were measured by radioimmunoassay and H. pylori infection was determined by histology and serum IgG antibodies.

RESULTS

Helicobacter pylori infection was present in 4 of 36 patients (11%) with BE and in 80 of 108 controls (74%), being less prevalent in BE patients than in the controls (P < 0.0001). When examined in the H. pylori-negative subjects, both the serum pepsinogen I and pepsinogen II concentrations in BE patients were significantly higher than those in the controls (mean pepsinogen I:BE 51.0 +/- 14.0 ng/mL vs control 38.9 +/- 13.5 ng/mL, P = 0.0012; mean pepsinogen II:BE 10.8 +/- 4.0 ng/mL vs control 7.9 +/- 2.0 ng/mL, P = 0.0097). There was no significant difference in the serum gastrin levels between BE patients and the controls irrespective of the H. pylori infection status.

CONCLUSIONS

Most of the Japanese BE patients are characterized by the absence of H. pylori infection and high levels of serum pepsinogen. Determination of the serum pepsinogen level in combination with the H. pylori infection status could be a useful serological marker for BE screening.

The role of Sp1 in IL-1beta and H. pylori-mediated regulation of H,K-ATPase gene transcription

Helicobacter pylori infection of the gastric body induces transient hypochlorhydria and contributes to mucosal progression toward gastric carcinoma. Acid secretion is mediated by parietal cell H,K-ATPase, in which the catalytic alpha-subunit (HKalpha) promoter activity in transfected gastric epithelial [gastric adenocarcinoma (AGS)] cells is repressed by H. pylori through NF-kappaB p50 homodimer binding to the promoter. IL-1beta, an acid secretory inhibitor whose mucosal level is increased by H. pylori, upregulates HKalpha promoter activity in AGS cells. Because IL-1beta also activates NF-kappaB signaling, we investigated disparate HKalpha regulation by H. pylori and IL-1beta, testing the hypothesis that IL-1beta-induced HKalpha promoter activation is mediated by the transcription factor Sp1. DNase I footprinting revealed Sp1 binding to the HKalpha promoter at -56 to -39 bp. IL-1beta stimulated the activity of three HKalpha promoter constructs containing NF-kappaB and Sp1 sites transfected into AGS cells and also stimulated a construct containing only an Sp1 site. This stimulation was abrogated by mutating the HKalpha promoter Sp1 binding site. Gelshift assays showed that IL-1beta increased Sp1 but not p50 binding to cognate HKalpha probes and that Sp1 also interacts with an HKalpha NF-kappaB site when bound to its cognate HKalpha cis-response element. H. pylori did not augment Sp1 binding to an HKalpha Sp1 probe, and small interfering RNA-mediated knockdown of Sp1 expression abrogated IL-1beta-induced HKalpha promoter stimulation. We conclude that IL-1beta upregulates HKalpha gene transcription by inducing Sp1 binding to HKalpha Sp1 and NF-kappaB sites and that the H. pylori perturbation of HKalpha gene expression is independent of Sp1-mediated basal HKalpha transcription.

Non-invasive tests in gastric diseases

Although the gastric cancer incidence is decreasing, this neoplasia remains one of the major causes of oncological mortality. Because of an insidious development, gastric cancer is often diagnosed in an advanced stage and consequently with a poor prognosis. Accurate non-invasive tests should be extremely useful in order to detect gastric neoplasm in an early phase. In clinical practice, there is no reliable bio-marker for detecting this malignant disease. However, intestinal as well as diffuse types of gastric cancer are preceded by gastric mucosa inflammation. Furthermore, the intestinal type of the neoplasia is, generally, related to chronic atrophic gastritis, especially if associated with intestinal metaplasia. In particular, the risk of the neoplasm is linked to both extension and severity of gastric atrophy. Serological parameters such as serum pepsinogens I (PGI) and II (PGII), gastrin-17 (G-17) cytokines (e.g. IL-8), antiparietal cells, IgG anti-Hp and CagA antibodies and lastly ghrelin supply information about either atrophic or inflammatory conditions characterising gastric mucosa. Low PGI and PGI/PGII ratio levels, especially if combined with high G-17 levels, are recognised bio-markers of corpus atrophic gastritis. Low G-17 levels could be, also, suggestive of antral atrophic gastritis. Furthermore, plasmatic ghrelin levels seem to be also a bio-marker of corpus atrophy. Anti-Hp IgG and CagA antibodies as well as PGII levels are able to detect gastric inflammation. Serological parameters could select subjects at risk for gastric mucosa alterations such as inflammation or atrophy, rather than gastric cancer itself. This review analyses the information derived from serological bio-markers as well as the involved clinical studies.

Control of gastric acid secretion in health and disease

Recent milestones in the understanding of gastric acid secretion and treatment of acid-peptic disorders include the (1) discovery of histamine H(2)-receptors and development of histamine H(2)-receptor antagonists, (2) identification of H(+)K(+)-ATPase as the parietal cell proton pump and development of proton pump inhibitors, and (3) identification of Helicobacter pylori as the major cause of duodenal ulcer and development of effective eradication regimens. This review emphasizes the importance and relevance of gastric acid secretion and its regulation in health and disease. We review the physiology and pathophysiology of acid secretion as well as evidence regarding its inhibition in the management of acid-related clinical conditions.

International variation in Helicobacter pylori infection and rates of oesophageal cancer

AIM

To examine the association between gastric atrophy, Helicobacter pylori and CagA status, and ratio of oesophageal squamous cell carcinoma to oesophageal adenocarcinoma (OSCC:OAC) amongst international heterogeneous populations.

METHODS

Standardised protocols were used to collect and process questionnaire data and serum samples for PgA and PgC levels and H. pylori and CagA serology. The OSCC:OAC were used to construct appropriate models.

RESULTS

There were significant correlations between the OSCC:OAC and both rates of low PgA:PgC ratios and serological markers of H. pylori infection, in males, but not females. A significant correlation between OSCC:OAC and overall CagA-seropositivity was seen in males, but not females, but this was not independently associated with increasing OSCC:OAC.

CONCLUSIONS

In males, populations with higher rates of gastric atrophy or H. pylori infection have a higher OSCC:OAC. CagA seropositivity rates seem to have no additional effect.