Antigenic mimicry between Helicobacter pylori and gastric mucosa in the pathogenesis of body atrophic gastritis

Gastric Non-Hodgkin Lymphoma in a Helicobacter pylori-Infected Patient

Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) is a rare gastric malignant neoplasm. While the association between Heliobacter pylori infection and gastric mucosa-assisted lymphoid tissue lymphoma is well established, data supporting its association with DLBCL are less robust. Here we present a rare case of PG-DLBCL diagnosed with H. pylori. An 82-year-old man presented to clinic with complaints of worsening epigastric pain. He underwent an endoscopy which revealed 1 large nonbleeding gastric ulcer. Histopathological and immunohistochemical analysis confirmed PG-DLBCL. He was started on H. pylori eradication (HPE) and subsequently completed 6 cycles of R-mini-CHOP chemotherapy. Since then, the patient maintained clinical and radiological remission for more than a year without recurrence. PG-DLBCL is an aggressive Non-hodgkin lymphoma (NHL) that usually presents late. It has been shown that HPE without chemotherapy in DLBCL codiagnosed with H. pylori is not an effective strategy. Thus, the standard of care for patients would be HPE and chemotherapy as in our patient. More research is needed to better understand association between H. pylori and DLBCL.

RE.GA.IN.: the Real-world Gastritis Initiative-updating the updates

At the end of the last century, a far-sighted 'working party' held in Sydney, Australia addressed the clinicopathological issues related to gastric inflammatory diseases. A few years later, an international conference held in Houston, Texas, USA critically updated the seminal Sydney classification. In line with these initiatives, Kyoto Global Consensus Report, flanked by the Maastricht-Florence conferences, added new clinical evidence to the gastritis clinicopathological puzzle.The most relevant topics related to the gastric inflammatory diseases have been addressed by the Real-world Gastritis Initiative (RE.GA.IN.), from disease definitions to the clinical diagnosis and prognosis. This paper reports the conclusions of the RE.GA.IN. consensus process, which culminated in Venice in November 2022 after more than 8 months of intense global scientific deliberations. A forum of gastritis scholars from five continents participated in the multidisciplinary RE.GA.IN. consensus. After lively debates on the most controversial aspects of the gastritis spectrum, the RE.GA.IN. Faculty amalgamated complementary knowledge to distil patient-centred, evidence-based statements to assist health professionals in their real-world clinical practice. The sections of this report focus on: the epidemiology of gastritis; Helicobacter pylori as dominant aetiology of environmental gastritis and as the most important determinant of the gastric oncogenetic field; the evolving knowledge on gastric autoimmunity; the clinicopathological relevance of gastric microbiota; the new diagnostic horizons of endoscopy; and the clinical priority of histologically reporting gastritis in terms of staging. The ultimate goal of RE.GA.IN. was and remains the promotion of further improvement in the clinical management of patients with gastritis.

Outcome and patterns of relapse in primary gastric diffuse large B cell lymphoma treated with RCHOP

OBJECTIVES

Patterns and predictors of relapse in primary gastric diffuse large B cell lymphoma (DLBCL) were variably reported. Our study aims to evaluate the patterns and predictors of relapse in early-stage gastric DLBCL treated with Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisolone (RCHOP).

METHODS

From 2005 to 2019, the medical records of 72 patients with stage I or stage II gastric DLBCL treated with six cycles of RCHOP without radiotherapy were reviewed. Different variables were correlated with progression free survival (PFS), overall survival (OS), and local relapse free survival (LRFS).

RESULTS

64 (88.1%) patients achieved a complete response (CR), while 8 (11.9%) had refractory disease. After CR, 9 (14%) patients relapsed; 7 (78%) relapses were loco-regional. Abnormal LDH (p = 0.028), H. pylori negative (p = 0.032) and, stage adjusted international prognostic index (sa-IPI) > 1 (p = 0.013) correlated with loco-regional failure. The 5-year PFS, OS, and LRFS were 74.8%, 75.3%, and 87.5%, respectively, after a median follow-up of 58 (range: 6-185) months. The median time to progression or relapse was 9 months (range: 5-54 months). In multivariate analysis, a sa-IPI >1 (HR: 3.56, CI: 1.35-8.8, p = 0.01) was associated with PFS while low albumin (HR: 8.85, CI: 1.09-71.4, p = 0.041) was associated with worse OS. None of the variables were associated with LRFS.

CONCLUSION

Treatment of primary gastric DLBCL with RCHOP results in a high CR rate. The majority of treatment failures were loco-regional. Sa-IPI and H. pylori status may be used to identify patients who may benefit from combined modality treatment.

Update on Serum Biomarkers in Autoimmune Atrophic Gastritis

BACKGROUND

Autoimmune atrophic gastritis (AAG) is a persistent, corpus-restricted immune-mediated destruction of the gastric corpus oxyntic mucosa with reduced gastric acid and intrinsic factor secretion, leading to iron deficiency and pernicious anemia as a consequence of iron and cobalamin malabsorption. Positivity toward parietal cell (PCA) and intrinsic factor (IFA) autoantibodies is very common. AAG may remain asymptomatic for many years, thus making its diagnosis complex and often delayed. Due to the increased risk of gastric neoplasms, a timely diagnosis of AAG is clinically important.

CONTENT

The gold standard for AAG diagnosis is histopathological assessment of gastric biopsies obtained during gastroscopy, but noninvasive, preendoscopic serological screening may be useful in some clinical scenarios. Serum biomarkers for AAG may be divided into 2 groups: gastric autoimmunity-related biomarkers, such as PCA and IFA, and gastric corpus atrophy/reduced gastric acid secretion-related biomarkers, such as serum gastrin and pepsinogens. The present review focuses on the clinical significance and pitfalls of serum biomarkers related to gastric autoimmunity and gastric corpus atrophy, including some discussion of analytical methods.

SUMMARY

Serum assays for PCA, IFA, gastrin, and pepsinogen I show good diagnostic accuracy for noninvasive diagnostic work-up of AAG. Diagnostic performance may increase by combining >1 of these tests, overcoming the problem of seronegative AAG. However, appropriately designed, comparative studies with well-characterized patient cohorts are needed to better define the reliability of these biomarkers in the diagnosis of patients with AAG. Currently, positive serum tests should always be followed by the state-of-art diagnostic test, that is, histopathological assessment of gastric biopsies obtained during gastroscopy to definitively confirm or rule out AAG and eventually neoplastic complications.

Increased Prevalence of Autoimmune Gastritis in Patients with a Gastric Precancerous Lesion

Background: Autoimmune gastritis (AIG), characterized with the presence of anti-parietal-cell antibodies (APCA), is a risk factor for gastric cancer. However, AIG may go underdiagnosed, especially in the case of H. pylori infection and the presence of gastric precancerous lesions (GPL), due to the ambiguous pathology and delayed symptom onset. Aim: Investigate the prevalence and characteristics of AIG in GPL patients. Methods: Prevalence of AIG was determined with the presence of APCA in patients with GPL (n = 256) and the control group (n = 70). Pathological characteristics and levels of gastrin 17 (G17), pepsinogen (PG) I and II and anti-Helicobacter pylori IgG were assessed in GPL cases, and the severity of intestinal metaplasia and gastric atrophy was scored by expert pathologists. Results: APCA positivity was observed in 18% of cases vs. 7% of controls (p = 0.033). Only 3/256 patients were previously diagnosed with AIG. The presence of APCA was associated with corpus-limited and extended GPL. A receiver operating curve analysis demonstrated that the G17 and PGI/II ratio could identify APCA-positive patients within GPL cases (AUC: 0.884). Conclusions: The prevalence of AIG is higher in patients with GPL but goes undiagnosed. Using G17 and PG I/II as diagnostic markers can help to identify patients with AIG and improve surveillance programs for patients with GPL.

Helicobacter pylori and the Role of Lipopolysaccharide Variation in Innate Immune Evasion

Helicobacter pylori is an important human pathogen that infects half the human population and can lead to significant clinical outcomes such as acute and chronic gastritis, duodenal ulcer, and gastric adenocarcinoma. To establish infection, H. pylori employs several mechanisms to overcome the innate and adaptive immune systems. H. pylori can modulate interleukin (IL) secretion and innate immune cell function by the action of several virulence factors such as VacA, CagA and the type IV secretion system. Additionally, H. pylori can modulate local dendritic cells (DC) negatively impacting the function of these cells, reducing the secretion of immune signaling molecules, and influencing the differentiation of CD4⁺ T helper cells causing a bias to Th1 type cells. Furthermore, the lipopolysaccharide (LPS) of H. pylori displays a high degree of phase variation and contains human blood group carbohydrate determinants such as the Lewis system antigens, which are proposed to be involved in molecular mimicry of the host. Lastly, the H. pylori group of outer membrane proteins such as BabA play an important role in attachment and interaction with host Lewis and other carbohydrate antigens. This review examines the various mechanisms that H. pylori utilises to evade the innate immune system as well as discussing how the structure of the H. pylori LPS plays a role in immune evasion.

Pernicious Anemia: The Hematological Presentation of a Multifaceted Disorder Caused by Cobalamin Deficiency

Pernicious anemia is still a neglected disorder in many medical contexts and is underdiagnosed in many patients. Pernicious anemia is linked to but different from autoimmune gastritis. Pernicious anemia occurs in a later stage of autoimmune atrophic gastritis when gastric intrinsic factor deficiency and consequent vitamin B₁₂ deficiency may occur. The multifaceted nature of pernicious anemia is related to the important role of cobalamin, which, when deficient, may lead to several dysfunctions, and thus, the proteiform clinical presentations of pernicious anemia. Indeed, pernicious anemia may lead to potentially serious long-term complications related to micronutrient deficiencies and their consequences and the development of gastric cancer and type 1 gastric neuroendocrine tumors. When not recognized in a timely manner or when pernicious anemia is diagnosed with delay, these complications may be potentially life-threatening and sometimes irreversible. The current review aimed to focus on epidemiology, pathogenesis, and clinical presentations of pernicious anemia in an attempt to look beyond borders of medical specialties. It aimed to focus on micronutrient deficiencies besides the well-known vitamin B₁₂ deficiency, the diagnostic approach for pernicious anemia, its long-term complications and optimal clinical management, and endoscopic surveillance of patients with pernicious anemia.

The role of advanced endoscopy in the management of inflammatory digestive diseases (upper gastrointestinal tract)

The Japan Gastroenterological Endoscopy Society held four serial symposia between 2019 and 2020 on the state-of-the-art of issues related to upper GI inflammatory diseases. This review discusses some of the topics addressed in these symposia. The papers regarding nonerosive reflux disease, recent improvements in intraesophageal pH-impedance monitoring and endoscopic diagnosis using image-enhanced endoscopy have been published. Many publications have addressed its usefulness in endoscopic treatment of gastroesophageal reflux disease such as anti-reflux mucosectomy. In the management of eosinophilic esophagitis, since the symptoms are subjective, objective indicators have been sought, and ultrasonography and high-resolution manometry may be useful tools for evaluation. The natural course of this condition, especially of asymptomatic cases, is not well clarified. Some newly developed anti-acid or anti-inflammatory medicines are now under investigation. With regard to autoimmune gastritis, because of widespread medical examinations, diagnosis of asymptomatic cases has been increasing. Recently, its endoscopic characteristics have become clear and the natural history of these conditions is being elucidated. The Kyoto Classification of Gastritis has been reported to be useful not only for Helicobacter pylori diagnosis but also for identification of risks of gastric cancer. Its usefulness is now recognized in Asia and Europe.

Two Distinct Etiologies of Gastric Cancer: Infection and Autoimmunity

Gastric cancer is a leading cause of mortality worldwide. The risk of developing gastric adenocarcinoma, which comprises >90% of gastric cancers, is multifactorial, but most associated with Helicobacter pylori infection. Autoimmune gastritis is a chronic autoinflammatory syndrome where self-reactive immune cells are activated by gastric epithelial cell autoantigens. This cause of gastritis is more so associated with the development of neuroendocrine tumors. However, in both autoimmune and infection-induced gastritis, high risk metaplastic lesions develop within the gastric mucosa. This warrants concern for carcinogenesis in both inflammatory settings. There are many similarities and differences in disease progression between these two etiologies of chronic gastritis. Both diseases have an increased risk of gastric adenocarcinoma development, but each have their own unique comorbidities. Autoimmune gastritis is a primary cause of pernicious anemia, whereas chronic infection typically causes gastrointestinal ulceration. Both immune responses are driven by T cells, primarily CD4⁺ T cells of the IFN-γ producing, Th1 phenotype. Neutrophilic infiltrates help clear H. pylori infection, but neutrophils are not necessarily recruited in the autoimmune setting. There have also been hypotheses that infection with H. pylori initiates autoimmune gastritis, but the literature is far from definitive with evidence of infection-independent autoimmune gastric disease. Gastric cancer incidence is increasing among young women in the United States, a population at higher risk of developing autoimmune disease, and H. pylori infection rates are falling. Therefore, a better understanding of these two chronic inflammatory diseases is needed to identify their roles in initiating gastric cancer.

Gastritis: The clinico-pathological spectrum

The inflammatory spectrum of gastric diseases includes different clinico-pathological entities, the etiology of which was recently established in the international Kyoto classification. A diagnosis of gastritis combines the information resulting form the gross examination (endoscopy) and histology (microscopy). It is important to consider the anatomical/functional heterogeneity of the gastric mucosa when obtaining representative mucosal biopsy samples. Gastritis includes self-limiting and non-self-limiting (long-standing) inflammatory diseases, and the latter are epidemiologically, biologically and clinically linked to the onset of gastric cancer (i.e. "inflammation-associated cancer"). Different biological models of inflammation-associated gastric oncogenesis have been proposed. Helicobacter pylori (H. pylori) gastritis is the most prevalent worldwide, and H. pylori is classified as a first-class carcinogen. On these bases, eradicating H. pylori is mandatory for the primary prevention of gastric cancer. Non-self-limiting gastritis may also be triggered by the immune-mediated destruction of gastric parietal cells, resulting in autoimmune gastritis. In both H. pylori-related and autoimmune gastritis, the non-self-limiting inflammation results in atrophy of the gastric mucosa, which is the main factor promoting gastric cancer. Long-term follow-up studies consistently demonstrate the prognostic impact of the histological staging of gastritis in gastric cancer secondary prevention strategies.

Gastritis, Gastric Polyps and Gastric Cancer

Gastric cancer is still an important disease causing many deaths worldwide, although there has been a marked reduction in prevalence during the last few decades. The decline in gastric cancer prevalence is due to a reduction in Helicobacter pylori infection which has occurred for at least 50 years. The most probable mechanism for the carcinogenic effect of H. pylori is hypergastrinemia since H. pylori infected individuals do not have increased risk of gastric cancer before the development of oxyntic atrophy. When atrophy has developed, the carcinogenic process continues independent of H. pylori. Autoimmune gastritis also induces oxyntic atrophy leading to marked hypergastrinemia and development of ECL cell neoplasia as well as adenocarcinoma. Similarly, long-term treatment with efficient inhibitors of acid secretion like the proton pump inhibitors (PPIs) predisposes to ECL cell neoplasia of a different degree of malignancy. Contrasting the colon where most cancers develop from polyps, most polyps in the stomach have a low malignant potential. Nevertheless, gastric polyps may also give rise to cancer and have some risk factors and mechanisms in common with gastric cancer. In this overview the most common gastric polyps, i.e., hyperplastic polyps, adenomatous polyps and fundic gland polyps will be discussed with respect to etiology and particularly use of PPIs and relation to gastric carcinogenesis.

The Role of Gastric Mucosal Immunity in Gastric Diseases

Gastric mucosa plays its immune function through innate and adaptive immunity by recruiting immune cells and releasing corresponding cytokines, which have an inseparable relationship with gastric diseases. Whether infective gastric diseases caused by Helicobacter pylori, Epstein-Barr virus or other microbe, noninfective gastric diseases, or gastric cancer, gastric mucosal immunity plays an important role in the occurrence and development of the disease. Understanding the unique immune-related tissue structure of the gastric mucosa and its role in immune responses can help prevent gastric diseases or treat them through immunotherapy. In this review, we summarize the basic feature of gastric mucosal immunity and its relationship with gastric diseases to track the latest progress of gastric mucosal immunity, update relevant knowledge and provide theoretical reference for the prevention and treatment of gastric diseases based on the gastric mucosal immunity.

Autoimmune gastritis

Autoimmune gastritis (AIG) is an increasingly prevalent, organ-specific, immune-mediated disorder characterized by the destruction of gastric parietal cells, leading to the loss of intrinsic factor and reduced acid output. These alterations result in malabsorption of iron, vitamin B₁₂ (pernicious anaemia) and potentially other micronutrients. For several years, most studies have focused on pernicious anaemia only, generating confusion between the two entities. In AIG, the gastric proton pump, H⁺/K⁺ ATPase, is the major autoantigen recognized by autoreactive T cells. The T cell-dependent activation of B cells stimulates the production of anti-parietal cell antibodies, the serological hallmark of AIG. The role of Helicobacter pylori infection in activating or favouring the autoimmune process is still uncertain. Early histopathological alterations allowing a more precise and prompt recognition have recently been described. AIG is burdened by a substantial diagnostic delay as it can present with varied clinical signs including, among others, gastrointestinal symptoms and neuropsychiatric manifestations. In advanced stages, AIG might progress to neuroendocrine tumours and gastric adenocarcinoma. Management includes early detection through a proactive case-finding strategy, micronutrient supplementation and endoscopic surveillance. This Primer comprehensively describes the most important insights regarding the epidemiology, pathophysiology, diagnosis and management of AIG, focusing on the most controversial, outstanding issues and future directions.

Anti-Glycan Autoantibodies Induced by Helicobacter pylori as a Potential Risk Factor for Myocardial Infarction

A number of epidemiological studies have evaluated the potential association between H. pylori and cardiovascular disease, but with contrasting results. We have previously shown that Helicobacter pylori infection is able to induce in mice and humans autoantibodies cross-reacting with histo–blood group Lewis antigens, expressed in different organs and in plasma glycoproteins and glycolipids. The aim of this study was to assess whether immunization of animals with H. pylori might induce myocardial histopathological changes. We have retrospectively examined, in detail, the histology of archived organs from mice and rabbits immunized with H. pylori in our previous studies. Human sera and cross-reacting monoclonal antibodies were also tested against bacterial preparations and tissue sections. Areas of myocardial necrosis, associated with coronary thrombotic occlusion, were found in 5 of 20 mice and 2 of 5 rabbits previously immunized with suspensions of H. pylori. No similar lesions were found in control animals, suggesting a causal link with H. pylori immunization. The animals bearing myocardial lesions had not been infected but only immunized months earlier with parenteral injections of dead H. pylori cells. This strongly suggests that immunization, by itself, might play a causative role. We propose that the cross-reactive autoimmune response induced by H. pylori could promote thrombotic occlusion through direct endothelial damage or by perturbing the coagulation process.

Aim2-mediated/IFN-β-independent regulation of gastric metaplastic lesions via CD8+ T cells

Development of gastric cancer is often preceded by chronic inflammation, but the immune cellular mechanisms underlying this process are unclear. Here we demonstrated that an inflammasome molecule, absent in melanoma 2 (Aim2), was upregulated in patients with gastric cancer and in spasmolytic polypeptide-expressing metaplasia of chronically Helicobacter felis-infected stomachs in mice. However, we found that Aim2 was not necessary for inflammasome function during gastritis. In contrast, Aim2 deficiency led to an increase in gastric CD8+ T cell frequency, which exacerbated metaplasia. These gastric CD8+ T cells from Aim2-/- mice were found to have lost their homing receptor expression (sphingosine-1-phosphate receptor 1 [S1PR1] and CD62L), a feature of tissue-resident memory T cells. The process was not mediated by Aim2-dependent regulation of IFN-β or by dendritic cell-intrinsic Aim2. Rather, Aim2 deficiency contributed to an increased production of CXCL16 by B cells, which could suppress S1PR1 and CD62L in CD8+ T cells. This study describes a potentially novel function of Aim2 that regulates CD8+ T cell infiltration and retention within chronically inflamed solid organ tissue. This function operates independent of the inflammasome, IFN-β, or dendritic cells. We provide evidence that B cells can contribute to this mechanism via CXCL16.

Chronic atrophic gastritis: Natural history, diagnosis and therapeutic management. A position paper by the Italian Society of Hospital Gastroenterologists and Digestive Endoscopists [AIGO], the Italian Society of Digestive Endoscopy [SIED], the Italian Society of Gastroenterology [SIGE], and the Italian Society of Internal Medicine [SIMI]

Chronic atrophic gastritis (CAG) is an underdiagnosed condition characterised by translational features going beyond the strict field of gastroenterology as it may manifest itself by a variable spectrum of gastric and extra-gastric symptoms and signs. It is relatively common among older adults in different parts of the world, but large variations exist. Helicobacter pylori-related CAG [multifocal] and autoimmune CAG (corpus-restricted) are apparently two different diseases, but they display overlapping features. Patients with cobalamin and/or iron deficiency anaemia or autoimmune disorders, including autoimmune thyroiditis and type 1 diabetes mellitus, should be offered screening for CAG. Pepsinogens, gastrin-17, and anti-H. pylori antibodies serum assays seem to be reliable non-invasive screening tools for the presence of CAG, helpful to identify individuals to refer to gastroscopy with five standard gastric biopsies in order to obtain histological confirmation of diagnosis. Patients with CAG are at increased risk of developing gastric cancer, and they should be estimated with histological staging systems (OLGA or OLGIM). H. pylori eradication may be beneficial by modifying the natural history of atrophy, but not that of intestinal metaplasia. Patients with advanced stages of CAG (Stage III/IV OLGA or OLGIM) should undergo endoscopic surveillance every three years, those with autoimmune CAG every three-five years. In patients with CAG, a screening for autoimmune thyroid disease and micronutrient deficiencies, including iron and vitamin B₁₂, should be performed. The optimal treatment for dyspeptic symptoms in patients with CAG remains to be defined. Proton pump inhibitors are not indicated in hypochlorhydric CAG patients.

Gastric cancer in autoimmune gastritis: A case-control study from the German centers of the staR project on gastric cancer research

Objectives

Patients with autoimmune gastritis (AIG) are reported to have an increased risk of developing gastric cancer (GC). In this study, we assess the characteristics and outcomes of GC patients with AIG in a multicenter case-control study.

Methods

Between April 2013 and May 2017, patients with GC, including cancers of the esophagogastric junction (EGJ) Siewert type II and III, were recruited. Patients with histological characteristics of AIG were identified and matched in a 1:2 fashion for age and gender to GC patients with no AIG. Presenting symptoms were documented using a self-administered questionnaire.

Results

Histological assessment of gastric mucosa was available for 572/759 GC patients. Overall, 28 (4.9%) of GC patients had AIG (67 ± 9 years, female-to-male ratio 1.3:1). In patients with AIG, GC was more likely to be localized in the proximal (i.e. EGJ, fundus, corpus) stomach (odds ratio (OR) 2.7, 95% confidence interval (CI) 1.0–7.1). In GC patients with AIG, pernicious anemia was the leading clinical sign (OR 22.0, 95% CI 2.6–187.2), and the most common indication for esophagogastroduodenoscopy (OR 29.0, 95% CI 7.2–116.4). GC patients with AIG were more likely to present without distant metastases (OR 6.2, 95% CI 1.3–28.8) and to be treated with curative intention (OR 3.0, 95% CI 1.0–9.0). The five-year survival rates with 95% CI in GC patients with and with no AIG were 84.7% (83.8–85.6) and 53.5% (50.9–56.1), respectively (OR 0.25, 95% CI 0.08–0.75, p = 0.001).

Conclusions

Pernicious anemia leads to earlier diagnosis of GC in AIG patients and contributes significantly to a better clinical outcome.

α-Lipoic Acid Inhibits IL-8 Expression by Activating Nrf2 Signaling in Helicobacter pylori-infected Gastric Epithelial Cells

Helicobacter pylori (H. pylori) causes gastritis and gastric cancers. Oxidative stress is involved in the pathological mechanism of H. pylori-induced gastritis and gastric cancer induction. Therefore, reducing oxidative stress may be beneficial for preventing the development of H. pylori-associated gastric diseases. Nuclear factor erythroid-2-related factor 2 (Nrf2) is a crucial regulator for the expression of antioxidant enzyme heme oxygenase-1 (HO-1), which protects cells from oxidative injury. α-Lipoic acid (α-LA), a naturally occurring dithiol, shows antioxidant and anti-inflammatory effects in various cells. In the present study, we examined the mechanism by which α-LA activates the Nrf2/HO-1 pathway, suppresses the production of pro-inflammatory cytokine interleukine-8 (IL-8), and reduces reactive oxygen species (ROS) in H. pylori-infected AGS cells. α-LA increased the level of phosphorylated and nuclear-translocated Nrf2 by decreasing the amount of Nrf2 sequestered in the cytoplasm by complex formation with Kelch-like ECH1-associated protein 1 (KEAP 1). By using exogenous inhibitors targeting Nrf2 and HO-1, we showed that up-regulation of activated Nrf2 and of HO-1 results in the α-LA-induced suppression of interleukin 8 (IL-8) and ROS. Consumption of α-LA-rich foods may prevent the development of H. pylori-associated gastric diseases by decreasing ROS-mediated IL-8 expression in gastric epithelial cells.

Prognostic significance of helicobacter pylori-infection in gastric diffuse large B-cell lymphoma

Background

Helicobacter pylori (H. pylori) is thought to have an oncogenic effect on the development of gastric malignancies. However, the effect of H. pylori status on the prognosis of gastric diffuse large B-cell lymphoma (DLBCL) remains unconfirmed. This study aimed to identify the prognostic importance of H. pylori infection in de novo gastric DLBCL.

Methods

One hundred and twenty-nine patients diagnosed with primary de novo gastric DLBCL at the West China Hospital of Sichuan University from 1st January 2009 to 31st May 2016 were included. The clinical features of the patients were documented. H. pylori status was assessed via urease breath tests and histologic examinations. The prognostic value of H. pylori was verified via univariate and multivariate analyses.

Results

Over a median follow-up of 52.2 months (range 4–116), the 5-year overall survival (OS) for all patients was 78.7%. Patients with H. pylori infections had significantly better 5-year PFS and OS than did the H. pylori-negative subgroup (5-year PFS, 89.3% vs. 74.1%, P = 0.040; 5-year OS, 89.7% vs. 71.8%, P = 0.033). Negative H. pylori status and poor ECOG performance were independent negative prognostic indicators for both PFS and OS (PFS, P = 0.045 and P = 0.001, respectively; OS, P = 0.021 and P < 0.001, respectively).

Conclusions

H. pylori status in de novo gastric DLBCL can be a promising predictor of disease outcome, and patients with negative H. pylori status require careful follow-up since they tend to have a worse outlook.

Insights Into Pediatric Autoimmune Gastritis: Is There a Role for Helicobacter pylori Infection?

OBJECTIVES

Autoimmune gastritis (AIG) is a chronic inflammatory condition of the gastric mucosa, mainly described in adults presenting with pernicious anemia. It results from antibody-mediated destruction of parietal cells, but the precise initiating event is unknown. The pathogenicity of Helicobacter pylori (H pylori) has been suggested but not established. This study aimed to better characterize AIG in pediatric patients and to address the possible role of H pylori infection.

METHODS

Descriptive single-center study, retrospectively describing 20 patients with a diagnosis of AIG based on positivity for anti-parietal cell autoantibodies, in addition to analytical and/or histological findings of oxyntic mucosa atrophy.

RESULTS

In the majority (18/20), AIG diagnosis was suggested during investigation of refractory iron-deficient anemia. One patient had dyspepsia and none of the others had gastrointestinal symptoms. Fifty-five percent (11/20) were H pylori positive, but there were no significant differences regarding mean hemoglobin values at presentation (10.6 ± 2.5 vs 9.5 ± 1.0 g/dL, P > 0.05), analytical indicators of gastric atrophy (gastrin, 564.4 ± 184 vs 721.2 ± 220.6 pg/mL, P > 0.05), or in the presence or the grade of oxyntic mucosa atrophy.

CONCLUSIONS

Our findings highlight that AIG may have an age-dependent presentation; thus, we can consider a pediatric phenotype that in contrast to adults, is manifested by refractory iron-deficient anemia and associated with parietal cell autoantibody positivity, but not intrinsic factor autoantibodies. A correlation between H pylori and AIG was not evident in the current study and it is still unclear whether H pylori is a trigger for AIG.

Gastric Neuroendocrine Tumor and Duodenal Gastrinoma With Chronic Autoimmune Atrophic Gastritis

Our group observed the first case of synchronous gastric neuroendocrine tumor (NET) and duodenal gastrinoma with autoimmune chronic atrophic gastritis (CAG), in the absence of Helicobacter pylori infection. Demographic, clinical, endoscopic, and pathologic data were abstracted from the electronic medical record at Mount Sinai Hospital from 2013 to 2015. The patient's anonymity was carefully protected, and informed consent was obtained for publication of protected health information. A 53-year-old woman with hypertension presented to Mount Sinai Hospital in June 2013 for a second opinion for management of gastric and duodenal NETs. After evaluation by gastroenterology and surgery, repeat upper endoscopy with ultrasound and fine-needle aspiration revealed multiple diminutive type I gastric NETs and 2 duodenal NETs, against a background of autoimmune CAG, with biopsy pathology negative for H. pylori. She subsequently underwent a transduodenal resection of the duodenal NETs, confirming low-grade, gastrin-positive, stage T2 duodenal NET. On routine follow-up over the next 2 years, clinical, radiographic, and endoscopic surveillance revealed no recurrent or metastatic gastric or duodenal disease. This first report of synchronous duodenal gastrinoma and gastric NET in the setting of autoimmune CAG can broaden our understanding of gastric NET pathophysiology.

Acid and the basis for cellular plasticity and reprogramming in gastric repair and cancer

Subjected to countless daily injuries, the stomach still functions as a remarkably efficient digestive organ and microbial filter. In this Review, we follow the lead of the earliest gastroenterologists who were fascinated by the antiseptic and digestive powers of gastric secretions. We propose that it is easiest to understand how the stomach responds to injury by stressing the central role of the most important gastric secretion, acid. The stomach follows two basic patterns of adaptation. The superficial response is a pattern whereby the surface epithelial cells migrate and rapidly proliferate to repair erosions induced by acid or other irritants. The stomach can also adapt through a glandular response when the source of acid is lost or compromised (that is, the process of oxyntic atrophy). We primarily review the mechanisms governing the glandular response, which is characterized by a metaplastic change in cellular differentiation known as spasmolytic polypeptide-expressing metaplasia (SPEM). We propose that the stomach, like other organs, exhibits marked cellular plasticity: the glandular response involves reprogramming mature cells to serve as auxiliary stem cells that replace lost cells. Unfortunately, such plasticity might mean that the gastric epithelium undergoes cycles of differentiation and de-differentiation that increase the risk of accumulating cancer-predisposing mutations.

Review: Impact of Helicobacter pylori on Alzheimer's disease: What do we know so far?

BACKGROUND

Helicobacter pylori has changed radically gastroenterologic world, offering a new concept in patients' management. Over time, more medical data gave rise to diverse distant, extragastric manifestations and interactions of the "new" discovered bacterium. Special interest appeared within the field of neurodegenerative diseases and particularly Alzheimer's disease, as the latter and Helicobacter pylori infection are associated with a large public health burden and Alzheimer's disease ranks as the leading cause of disability. However, the relationship between Helicobacter pylori infection and Alzheimer's disease remains uncertain.

METHODS

We performed a narrative review regarding a possible connection between Helicobacter pylori and Alzheimer's disease. All accessible relevant (pre)clinical studies written in English were included. Both affected pathologies were briefly analyzed, and relevant studies are discussed, trying to focus on the possible pathogenetic role of this bacterium in Alzheimer's disease.

RESULTS

Data stemming from both epidemiologic studies and animal experiments seem to be rather encouraging, tending to confirm the hypothesis that Helicobacter pylori infection might influence the course of Alzheimer's disease pleiotropically. Possible main mechanisms may include the bacterium's access to the brain via the oral-nasal-olfactory pathway or by circulating monocytes (infected with Helicobacter pylori due to defective autophagy) through disrupted blood-brain barrier, thereby possibly triggering neurodegeneration.

CONCLUSIONS

Current data suggest that Helicobacter pylori infection might influence the pathophysiology of Alzheimer's disease. However, further large-scale randomized controlled trials are mandatory to clarify a possible favorable effect of Helicobacter pylori eradication on Alzheimer's disease pathophysiology, before the recommendation of short-term and cost-effective therapeutic regimens against Helicobacter pylori-related Alzheimer's disease.

Association between Helicobacter Pylori Infection and Alopecia Areata: A Study in Iranian Population

BACKGROUND Alopecia areata is an immune mediated inflammatory hair loss, which occurs in all ethnic and age groups, and both sexes. However no significant etiology has been known for this disease. Helicobacter pylori (H. pylori) , is an organism colonized in gastric mucosa. This bacterium has been associated with certain extra-digestive dermatological conditions. The causal relationship between alopecia areata and H. pylori infection has been discussed in literature. Therefore, we conducted this study to evaluate the prevalence of H. pylori infection in patients with alopecia areata and assess the risk of this infection in patients with this disease in order to determine its potential roles in the physiopathology of this disease. METHODS Between 2014 and 2015, we prospectively studied 81 patients with alopecia areata and 81 healthy volunteers with similar age and sex. Patients without any history of H. pylori infection were included in the study and underwent urease breath test. All results were analyzed using SPSS software (version 21.0) and p value<0.05 was considered as statistically significant. RESULTS 81 patients and 81 controls with the mean age of 34.9±11.6 and 38.2±13.4 years were studied (p=0.097). 48 (59.3%) and 45 (55.6%) individuals were male, in cases and control groups respectively (p =0.634). The result of urea breath test (UBT) was positive in 43 (53.1%) patients in cases and 27 (33.3%) individuals in control group, which was significantly different (p =0.011). The risk of H. pylori infection in alopecia areata was 2.263 (95% CI: 1.199-4.273). CONCLUSION The results of our study showed significant difference between H. pylori infection in individuals with and without alopecia areata, which shows that H. pylori contamination may be effective in physiopathology of alopecia areata. Therefore these results should be tested in large multivariable cohorts and controlled trials to reach more accurate evidence in the future and to generalize this idea to larger population.

Autoimmune atrophic gastritis: current perspectives

At present there is no universally accepted classification for gastritis. The first successful classification (The Sydney System) that is still commonly used by medical professionals was first introduced by Misiewicz et al in Sydney in 1990. In fact, it was the first detailed classification after the discovery of Helicobacter pylori by Warren and Marshall in 1982. In 1994, the Updated Sydney System was proposed during the International Workshop on the Histopathology of Gastritis followed by the publication in The American Journal of Surgical Pathology by Dixon et al. Using the new classification, distinction between atrophic and nonatrophic gastritis was revised, and the visual scale grading was incorporated. According to the Updated Sydney System Classification, atrophic gastritis is categorized into multifocal (H. pylori, environmental factors, specific diet) and corpus-predominant (autoimmune). Since metaplasia is a key histological characteristic in patients with atrophic gastritis, it has been recommended to use the word “metaplastic” in both variants of atrophic gastritis: autoimmune metaplastic atrophic gastritis (AMAG) and environmental metaplastic atrophic gastritis. Although there are many overlaps in the course of the disease and distinction between those two entities may be challenging, the aim of this review article was to describe the etiology, epidemiology, pathogenesis, diagnosis, clinical manifestations and treatment in patients with AMAG. However, it is important to mention that H. pylori is the most common etiologic factor for the development of gastritis in the world.

Role of Dietary Metabolites in Regulating the Host Immune Response in Gastrointestinal Disease

The host immune response to gastrointestinal (GI) infections, hypersensitivity reactions, or GI cancers comprises numerous pathways that elicit responses on different host cells. Some of these include (1) the stimulation of mast cells via their IgE receptor, (2) the production of antibodies leading to antibody-mediated cytotoxic T/natural killer cell killing, (3) the activation of the complement pathway, and (4) the activation of the adaptive immune response via antigen-presenting cell, T cell, and B cell interactions. Within the plethora of these different responses, several host immune cells represent major key players such as those of myeloid lineage (including neutrophils, macrophages, myeloid-derived suppressor cells) or lymphoid lineage (including T and B cells). In this review, we focus on newly identified metabolites and metabolite receptors that are expressed by either myeloid or lymphoid lineages. Irrespective of their source, these metabolites can in certain instances elicit responses on a wide range of cell types. The myeloid-expressed metabolic enzymes and receptors which we will discuss in this review include arginase 2 (Arg2), indoleamine-2,3-dioxygenase 1 (IDO1), hydroxycarboxylic acid receptor 2 (Hcar2; also called GPR109A), and immunoresponsive gene 1 (Irg1). We will also review the role of the lymphoid-expressed metabolite receptor that binds to the sphingosine-1-phosphate (S1P) sphingolipid. Moreover, we will describe the synthesis and metabolism of retinoic acid, and its effect on T cell activation. The review will then discuss the function of these metabolites in the context of GI disease. The review provides evidence that metabolic pathways operate in a disease- and context-dependent manner-either independently or concomitantly-in the GI tract. Therefore, an integrated approach and combinatorial analyses are necessary to devise new therapeutic strategies that can synergistically improve prognoses.

Lipopolysaccharide Structure and Biosynthesis in Helicobacter pylori

This review covers the current knowledge and gaps in Helicobacter pylori lipopolysaccharide (LPS) structure and biosynthesis. H. pylori is a Gram-negative bacterium which colonizes the luminal surface of the human gastric epithelium. Both a constitutive alteration of the lipid A preventing TLR4 elicitation and host mimicry of the Lewis antigen decorated O-antigen of H. pylori LPS promote immune escape and chronic infection. To date, the complete structure of H. pylori LPS is not available, and the proposed model is a linear arrangement composed of the inner core defined as the hexa-saccharide (Kdo-LD-Hep-LD-Hep-DD-Hep-Gal-Glc), the outer core composed of a conserved trisaccharide (-GlcNAc-Fuc-DD-Hep-) linked to the third heptose of the inner core, the glucan, the heptan and a variable O-antigen, generally consisting of a poly-LacNAc decorated with Lewis antigens. Although the glycosyltransferases (GTs) responsible for the biosynthesis of the H. pylori O-antigen chains have been identified and characterized, there are many gaps in regard to the biosynthesis of the core LPS. These limitations warrant additional mutagenesis and structural studies to obtain the complete LPS structure and corresponding biosynthetic pathway of this important gastric bacterium.

Review: Molecular mimicry of host structures by lipopolysaccharides of Campylobacter and Helicobacter spp.: implications in pathogenesis

Molecular mimicry of host structures by the saccharide portion of lipopolysaccharide (LPS) contributes to the virulence of certain strains of mucosal pathogens. Mimicry by the low molecular weight (low-Mr) LPSs of Neisseria and Haemophilus spp. have been the most extensively studied. However, studies within the last decade have revealed other types of mimicry within the saccharide moieties of LPSs of the enteric pathogen Campylobacter jejuni and the gastroduodenal pathogen Helicobacter pylori. The core oligosaccharides of low-Mr LPSs of C. jejuni serotypes which are associated with the development of Guillain-Barré syndrome (GBS), a neurological disorder, exhibit mimicry of gangliosides. Cross-reactive antibodies between LPSs and gangliosides which are induced during antecedent C. jejuni infection are considered to play an important role in GBS pathogenesis. The O-polysaccharide chains of high-Mr LPSs of a number of H. pylori strains mimic Lewisx and/or Lewisy blood group antigens. This mimicry may camouflage the bacterium in the gastric mucosa upon initial infection. With the progression of infection, the mimicry may play a role in immune response regulation and the induction of autoantibodies against the gastric proton pump, a glycoprotein that also expresses Lewis antigens.

Serum antibody response against Helicobacter pylori NCTC 11637 smooth- and rough-lipopolysaccharide phenotypes in patients with H. pylori-related gastropathy

The antigenicity of the Helicobacter pylori lipopolysaccharide (LPS) molecule during the course of natural H. pylori infection in humans was investigated. The IgG and IgA responses against smooth (S)- and rough (R)-form LPS were evaluated in H. pylori positive patients with chronic gastritis (CG, n = 30) and duodenal ulcer disease (DU, n = 16), and in 15 H. pylori-negative dyspeptic subjects. The results demonstrated that anti H. pylori LPS IgG and IgA antibody levels were significantly enhanced in both groups of H. pylori-positive patients compared with H. pylori-negative subjects, thus confirming that H. pylori LPS is part of the immunogenic antigen profile of the bacterium. In addition, a marked response against R-LPS, which significantly correlated with that observed against S-LPS, was found for both IgG and IgA, thus indicating that core oligosaccharide plays a powerful immunogenic role. Since the O-side chain of LPS from H. pylori NCTC 11637 contains epitopes which mimic Lewis x (Lex) antigens, the presence of antibodies to monomeric, trimeric, and polymeric Lex was also investigated. Antibodies against polymeric Lex were detected in two patients suffering from chronic atrophic gastritis and active chronic gastritis, respectively.

Lipopolysaccharide modification in Gram-negative bacteria during chronic infection

The Gram-negative bacterial lipopolysaccharide (LPS) is a major component of the outer membrane that plays a key role in host-pathogen interactions with the innate immune system. During infection, bacteria are exposed to a host environment that is typically dominated by inflammatory cells and soluble factors, including antibiotics, which provide cues about regulation of gene expression. Bacterial adaptive changes including modulation of LPS synthesis and structure are a conserved theme in infections, irrespective of the type or bacteria or the site of infection. In general, these changes result in immune system evasion, persisting inflammation and increased antimicrobial resistance. Here, we review the modifications of LPS structure and biosynthetic pathways that occur upon adaptation of model opportunistic pathogens (Pseudomonas aeruginosa, Burkholderia cepacia complex bacteria, Helicobacter pylori and Salmonella enterica) to chronic infection in respiratory and gastrointestinal sites. We also discuss the molecular mechanisms of these variations and their role in the host-pathogen interaction.

Activation of NF-κB and AP-1 Mediates Hyperproliferation by Inducing β-Catenin and c-Myc in Helicobacter pylori-Infected Gastric Epithelial Cells

PURPOSE

In the gastric mucosa of Helicobacter pylori (H. pylori)-infected patients with gastritis or adenocarcinoma, proliferation of gastric epithelial cells is increased. Hyperproliferation is related to induction of oncogenes, such as β-catenin and c-myc. Even though transcription factors NF-κB and AP-1 are activated in H. pylori-infected cells, whether NF-κB or AP-1 regulates the expression of β-catenein or c-myc in H. pylori-infected cells has not been clarified. The present study was undertaken to investigate whether H. pylori-induced activation of NF-κB and AP-1 mediates the expression of oncogenes and hyperproliferation of gastric epithelial cells.

MATERIALS AND METHODS

Gastric epithelial AGS cells were transiently transfected with mutant genes for IκBα (MAD3) and c-Jun (TAM67) or treated with a specific NF-κB inhibitor caffeic acid phenethyl ester (CAPE) or a selective AP-1 inhibitor SR-11302 to suppress activation of NF-κB or AP-1, respecively. As reference cells, the control vector pcDNA was transfected to the cells. Wild-type cells or transfected cells were cultured with or without H. pylori.

RESULTS

H. pylori induced activation of NF-κB and AP-1, cell proliferation, and expression of oncogenes (β-catenein, c-myc) in AGS cells, which was inhibited by transfection of MAD3 and TAM67. Wild-type cells and the cells transfected with pcDNA showed similar activities of NF-κB and AP-1, proliferation, and oncogene expression regardless of treatment with H. pylori. Both CAPE and SR-11302 inhibited cell proliferation and expression of oncogenes in H. pylori-infected cells.

CONCLUSION

H. pylori-induced activation of NF-κB and AP-1 regulates transcription of oncogenes and mediates hyperproliferation in gastric epithelial cells.

Current views of the relationship between Helicobacter pylori and Henoch-Schonlein purpura in children

Helicobacter pylori (H. pylori) is one of the factors involved in the pathogenesis of various gastrointestinal diseases and may play a potential role in certain extra-intestinal diseases. H. pylori infection are mainly acquired during childhood, and it has been reported that in endemic areas of China the infection rates are extraordinarily higher in HSP children, particular those with abdominal manifestations. Furthermore, eradication therapy may ameliorate Henoch-Schonlein purpura (HSP) manifestations and decrease the recurrence of HSP. Therefore, results suggested that detection of H. pylori infection by appropriate method ought to be applied in HSP children. Current evidences indicate that local injury of gastric mucosa and immunological events induced by H. pylori infection are involved in the development of HSP. Increased serum IgA, cryoglobulins, C3 levels, autoimmunity, proinflammatory substances and molecular mimicry inducing immune complex and cross-reactive antibodies caused by H. pylori infection might play their roles in the course of HSP. However, there are no investigations confirming the causality between H. pylori infection and HSP, and the pathogenesis mechanism is still unclear. More bench and clinical studies need to be executed to elaborate the complex association between H. pylori and HSP.

Evaluation of the Correlation Between Childhood Asthma and Helicobacter pylori in Kashan

Background:

Asthma is a chronic inflammatory air-way disease with increasing prevalence rate during the recent years. There are studies about the relationship between asthma and infectious diseases, including the association between asthma and Helicobacter pylori. According to the latest studies, there is an epidemiological correlation between asthma prevalence and prevalence of H. pylori.

Objectives:

The aim of this research was to study the correlation between H. pylori and asthma by biopsy in five to eighteen year-old children who had undergone endoscopy at Shahid Beheshti Hospital.

Patients and Methods:

Three hundred children (5 to 18 years old) undergoing endoscopy owing to gastro-intestinal problems at Shahid Beheshti Hospital were observed for childhood asthma using the Gina 2010 questionnaire which included 24 questions with “yes” and “no” answers to identify asthmatic patients with five positive answers. Next, the patients were referred to an allergy and asthma specialist for clinical examinations, spirometry and post bronchodilator test (Post BD).

Results:

Among 138 H. pylori positive patients, eight cases (5.8 %) were asthmatic while of the 162 H. pylori negative patients 28 (17.3%) were asthmatic. This difference was statistically significant (P Value = 0.002). The correlation between H. pylori and asthma was studied after controlling the confounding variables including, gender, age and family history. The results obtained for the above-mentioned variables were significant (P Values of 0.004, 0.005 and 0.002, and Odd-Ratio Mantel Haenszel (ORMH) of 3.38, 3.24 and 4.06, respectively).

Conclusions:

Our findings showed that there is an inverse correlation between H. pylori and asthma. Performing more studies with larger sample sizes is necessary to confirm these results.

Autoimmune gastritis in autoimmune thyroid disease

BACKGROUND

Autoimmune gastritis leads to oxyntic gastric atrophy, a condition at increased risk for gastric cancer. Autoimmune gastritis in conjunction with autoimmune thyroid disease has been reported previously.

AIM

In a case-control study in patients with autoimmune thyroid disease to evaluate the usefulness of serum pepsinogens for the identification of oxyntic gastric atrophy, and to determine the relationship of Helicobacter pylori with oxyntic gastric atrophy.

METHODS

Patients with autoimmune thyroid disease (cases) and goitre (controls) were prospectively enrolled in the study. Pepsinogen (PG) I levels ≤25 μg/mL and PG I/II ratio ≤3 were indicative for oxyntic gastric atrophy. Antibodies against H. pylori, CagA and parietal cells were also determined. Esophagogastroduodenoscopy with biopsies was offered to patients with serological oxyntic gastric atrophy.

RESULTS

In total, 34 autoimmune thyroid disease patients and 30 controls were enrolled. Serological oxyntic gastric atrophy was present only in autoimmune thyroid disease patients (8/34, 23.5%, OR 8.3, 95% CI = 1.9-36.2). In all eight patients oxyntic gastric atrophy was confirmed by histology. OLGA stage I, II, III and IV was described in 0%, 33%, 50% and 17% of the cases, respectively. About, 89% and 11% of oxyntic gastric atrophy patients were seropositive for antibodies against parietal cells or H. pylori infection, respectively. Gastric atrophy involved the angulus/antrum in 50% of patients with autoimmune gastritis.

CONCLUSIONS

The seroprevalence of oxyntic gastric atrophy is high in patients with autoimmune thyroid disease, and testing of serum pepsinogens should be included in the clinical assessment of these patients. H. pylori infection is unlikely to be a principal factor in the pathogenesis of oxyntic gastric atrophy in patients with autoimmune thyroid disease. In autoimmune gastritis, gastric atrophy can spread from the oxyntic towards the antral mucosa.

Serum OPN expression for identification of gastric cancer and atrophic gastritis and its influencing factors

Background

Most studies have found that osteopontin (OPN) expression level is related to the poor prognosis of gastric cancer. However, few studies have examined the relationship between OPN expression and gastric precancerous diseases, and the potential role of OPN in the formation and development of GC. We investigated the relationships between serum OPN levels and the risks of gastric cancer (GC) and its precancerous disease, to explore the diagnostic efficacy of serum OPN level for GC and atrophic gastritis and its influencing factors.

Methods

A total of 1,452 patients were enrolled, including 609 with mild superficial gastritis (SG), 594 with atrophic gastritis (AG) and 249 with GC. The levels of serum OPN and serum Helicobacter pylori IgG antibody were detected by enzyme-linked immunosorbent assay.

Results

Serum OPN levels increased from mild SG (1.99±1.91 ng/ml) to AG (2.37±2.27 ng/ml) to GC (5.94±4.52 ng/ml) (P≤0.002), along with increasing severity of gastric disease. OPN levels were significantly higher in patients with GC compared with the non-cancer population (2.17±2.10, P<0.0001). Serum OPN level was positively correlated with age and was higher in men than women, but was not correlated with H. pylori infection status. The area under the receiver operating characteristic curve was 0.805, the optimal cutoff was 2.56 ng/ml and the sensitivity and specificity were 74.3% and 71.8%, respectively, for the ability of serum OPN to discriminate GC.

Conclusions

Serum OPN expression was closely related to the risks of GC and AG, and it might be a useful marker for the discrimination of GC. OPN level was positively correlated with age and male sex, but was not affected by H. pylori infection, and it was promoted by smoking and drinking, in patients with mild SG.

Association between Helicobacter pylori infection and migraine: A meta-analysis

AIM: To quantify the association between Helicobacter pylori (H. pylori) infection and migraine.

METHODS: A systematic literature search of PubMed and EMBASE was conducted from inception to December 2013. Studies that provided data dealing with H. pylori infection in patients with migraine, as well as healthy controls, were selected. Meta-analysis was carried out using the odds ratio (OR) with a fixed or random effects model, and a 95%CI for the OR was calculated. An unconditional logistic regression model was used to analyze potential parameters related to H. pylori prevalence. Subgroup analyses were conducted as methods of detection and evidence grade.

RESULTS: Five case-control studies published between 2000 and 2013 were finally identified, involving 903 patients, with a total H. pylori infection rate of 39.31%. The prevalence of H. pylori infection was significantly greater in migraineurs than in controls (44.97% vs 33.26%, OR = 1.92, 95%CI: 1.05-3.51, P = 0.001). A sensitivity test indicated that no single study dominated the combined results. Univariate regression analysis found that publication year, geographical distribution and evidence grade were relevant to the results and were the main reason for the heterogeneity. Subgroup analysis found a significantly greater infection rate of H. pylori in Asian patients with migraine, but no statistically significant infection rate in European patients. The ORs were 3.48 (95%CI: 2.09-5.81, P = 0.000) and 1.19 (95%CI: 0.86-1.65, P = 0.288), respectively.

CONCLUSION: The pooled data suggest a trend of more frequent H. pylori infections in patients with migraine.

Clinical features and management of type I gastric carcinoids

Type I gastric carcinoids (TIGCs) are related to chronic atrophic gastritis and are characterized by hypergastrinemia and hyperplasia of enterochromaffin-like cells. TIGCs are the most frequently diagnosed of all gastric carcinoids, accounting for about 70-80 %. Endoscopically, TIGCs are present as small (<10 mm), polypoid lesions or, more frequently, as smooth, rounded submucosal lesions. Histologically, TIGCs arise in the deep mucosa, with some invading the submucosa. Most TIGCs are well-differentiated tumors, with metastasis being rare. Therefore, patients with TIGCs generally have an excellent prognosis. Among the currently available treatment options are total gastrectomy, partial resection, antrectomy, endoscopic resection, and endoscopic surveillance, although no consensus has been reached on their optimal management. Further studies are needed to develop better management options for patients with TIGC.

Autoimmune atrophic gastritis--pathogenesis, pathology and management

Autoimmune gastritis is a chronic progressive inflammatory condition that results in the replacement of the parietal cell mass by atrophic and metaplastic mucosa. A complex interaction of autoantibodies against the parietal cell proton pump and sensitized T cells progressively destroy the parietal cells, inducing hypochlorhydria and then achlorhydria, while autoantibodies against the intrinsic factor impair the absorption of vitamin B₁₂. The resulting cobalamin deficiency manifests with megaloblastic anaemia and neurological and systemic signs and symptoms collectively known as pernicious anaemia. Previously believed to be predominantly a disease of elderly women of Northern European ancestry, autoimmune gastritis has now been recognized in all populations and ethnic groups, but because of the complexity of the diagnosis no reliable prevalence data are available. For similar reasons, as well as the frequent and often unknown overlap with Helicobacter pylori infection, the risk of gastric cancer has not been adequately assessed in these patients. This Review summarizes the epidemiology, pathogenesis and pathological aspects of autoimmune metaplastic atrophic gastritis. We also provide practical advice for the diagnosis and management of patients with this disease.

Prevalence of virulent Helicobacter pylori strains in patients affected by idiopathic dysrhythmias

Helicobacter pylori virulent strains have been shown to affect cardiovascular diseases through molecular mimicry mechanisms. Silent autoimmune myocarditis has been hypothesized to be the cause of idiopathic dysrhythmias (IA). The aim of this study is to assess the prevalence of virulent H. pylori strains in patients affected by IA. In this study,54 patients (40 men, mean age 44 ± 17 years) affected by IA and 50 healthy subjects (34 men, mean age 45 ± 9) were evaluated. IA, defined as dysrhythmias with no evidence of other cardiac pathology, were either supraventricular (SVA, 23 patients; mean age 45 ± 15 years) or ventricular (VA, 31 patients; mean age 42 ± 18 years). H. pylori infection and gastrointestinal (GI) symptoms were evaluated. H. pylori strains expressing the cytotoxin-associated gene A (cagA) and the vacuolating-cytotoxin A (vacA) were also assessed through western blot. The prevalence of H. pylori is similar in IA patients and in controls (42 vs. 44%; p > 0.05); H. pylori infection is observed in 48 and 39% of the patients are affected by SVA and VA, respectively. The prevalence of CagA-positive strains is increased in IA patients compared to controls (65 vs. 42%; p < 0.01); similarly, the prevalence of VacA-positive strains is also increased in IA patients (74 vs. 46%; p < 0.006). Excluding belching, infected patients did not show any difference in GI symptoms, when compared to non-infected subjects. From this study it is concluded that there is an epidemiological link between CagA and VacA-positive H. pylori strains in IA patients.

Is Helicobacter pylori infection associated with Henoch-Schonlein purpura in Chinese children? a meta-analysis

BACKGROUND

The prevalence of Helicobacter pylori (H. pylori) infection is high in China. It not only causes the damage of gastric epithelium, but also plays a potential pathogenic role in several extraintestinal diseases. Henoch-Schonlein purpura (HSP) is one of the most common vasculitis syndromes affecting children. Although its cause is unclear, HSP is often considered to be associated with infectious agents. This metaanalysis of previously published studies was conducted using a predefined protocol to evaluate the underlying association between H. pylori infection and HSP in Chinese children.

METHODS

Predefined search strategy and inclusion criteria were set up to select studies reporting the prevalence of H. pylori infection among HSP children and control groups. Included studies were subjected to quality assessment and data extraction by two independent reviewers. The pooled odds ratio (OR) was calculated as the effect size via both traditional and cumulative meta-analysis. Heterogeneity was investigated by subgroup analysis, and the nonparametric "trim and fill" method was performed to adjust the overall estimate for the existence of publication bias.

RESULTS

Ten eligible studies covering 749 HSP children and 560 controls were included for metaanalysis. Observational epidemiology studies clearly aimed at detecting the potential association between H. pylori infection and HSP with retrospective data collection from the children enrolled consecutively. Overall, 49.27% (369/749) of HSP children had evidence of H. pylori infection compared with 23.39% (131/560) of children in the control group. The pooled OR of H. pylori infection in HSP children (10 studies with 749 HSP children) was 3.80 [95% confidence interval (CI): 2.54-5.68, P<0.001], and the overall estimate from the cumulative meta-analysis confirmed the association with more narrow confidence interval (OR=3.35, 95% CI: 2.95-3.81). In HSP children mainly with abdominal manifestations (8 studies with 337 HSP children), the pooled OR was 4.62 (95% CI: 2.66-8.01, P<0.001). The adjusted pooled OR was 2.04 (95% CI: 1.48-2.82, P<0.001), determined by the nonparametric "trim-andfill" method for eliminating the effect of publication bias. H. pylori eradication therapy (4 studies with 266 HSP children) was capable of reducing the recurrence of HSP (RR=0.38, 95% CI: 0.25-0.58, P<0.001). Although the subgroup analysis for heterogeneity suggested that diagnostic methods and geographical diversity might be account for the heterogeneity, statistical analysis of differences revealed no differences between subgroups, indicating their limited impact on the overall estimates.

CONCLUSIONS

These results suggest the necessity of screening H. pylori infection in HSP children, particularly in those with gastrointestinal manifestations in China. Eradication therapy may reduce the recurrence of HSP in children with H. pylori infection. However, further mechanistic and more clinical studies in different populations and regions are needed to confirm this association and the effect of eradication of H. pylori in HSP children.