Immunological Perspective: Helicobacter pylori Infection and Gastritis.

Helicobacter pylori is a spiral-shaped gram-negative bacterium. Its infection is mainly transmitted via oral-oral and fecal-oral routes usually during early childhood. It can achieve persistent colonization by manipulating the host immune responses, which also causes mucosal damage and inflammation. H. pylori gastritis is an infectious disease and results in chronic gastritis of different severity in near all patients with infection. It may develop from acute/chronic inflammation, chronic atrophic gastritis, intestinal metaplasia, dysplasia, and intraepithelial neoplasia, eventually to gastric cancer. This review attempts to cover recent studies which provide important insights into how H. pylori causes chronic inflammation and what the characteristic is, which will immunologically explain H. pylori gastritis.

Glucocorticoids and Androgens Protect From Gastric Metaplasia by Suppressing Group 2 Innate Lymphoid Cell Activation.

BACKGROUND & AIMS: The immune compartment is critical for maintaining tissue homeostasis. A weak immune response increases susceptibility to infection, but immune hyperactivation causes tissue damage, and chronic inflammation may lead to cancer development. In the stomach, inflammation damages the gastric glands and drives the development of potentially preneoplastic metaplasia. Glucocorticoids are potent anti-inflammatory steroid hormones that are required to suppress gastric inflammation and metaplasia. However, these hormones function differently in males and females. Here, we investigate the impact of sex on the regulation of gastric inflammation. METHODS: Endogenous glucocorticoids and male sex hormones were removed from mice using adrenalectomy and castration, respectively. Mice were treated with 5α-dihydrotestosterone (DHT) to test the effects of androgens on regulating gastric inflammation. Single-cell RNA sequencing of gastric leukocytes was used to identify the leukocyte populations that were the direct targets of androgen signaling. Type 2 innate lymphoid cells (ILC2s) were depleted by treatment with CD90.2 antibodies. RESULTS: We show that adrenalectomized female mice develop spontaneous gastric inflammation and spasmolytic polypeptide-expressing metaplasia (SPEM) but that the stomachs of adrenalectomized male mice remain quantitatively normal. Simultaneous depletion of glucocorticoids and sex hormones abolished the male-protective effects and triggered spontaneous pathogenic gastric inflammation and SPEM. Treatment of female mice with DHT prevented gastric inflammation and SPEM development when administered concurrent with adrenalectomy and also reversed the pathology when administered after disease onset. Single-cell RNAseq of gastric leukocytes revealed that ILC2s expressed abundant levels of both the glucocorticoid receptor (Gr) and androgen receptor (Ar). We demonstrated that DHT treatment potently suppressed the expression of the proinflammatory cytokines Il13 and Csf2 by ILC2s. Moreover, ILC2 depletion protected the stomach from SPEM development. CONCLUSIONS: Here, we report a novel mechanism by which glucocorticoids and androgens exert overlapping effects to regulate gastric inflammation. Androgen signaling within ILC2s prevents their pathogenic activation by suppressing the transcription of proinflammatory cytokines. This work revealed a critical role for sex hormones in regulating gastric inflammation and metaplasia.

Inflammation-Associated Senescence Promotes Helicobacter pylori-Induced Atrophic Gastritis.

BACKGROUND & AIMS: The association between cellular senescence and Helicobacter pylori-induced atrophic gastritis is not clear. Here, we explore the role of cellular senescence in H pylori-induced atrophic gastritis and the underlying mechanism. METHODS: C57BL/6J mice were infected with H pylori for biological and mechanistic studies in vivo. Gastric precancerous lesions from patients and mouse models were collected and analyzed using senescence-associated beta-galactosidase, Sudan Black B, and immunohistochemical staining to analyze senescent cells, signaling pathways, and H pylori infection. Chromatin immunoprecipitation, luciferase reporter assays, and other techniques were used to explore the underlying mechanism in vitro. RESULTS: Gastric mucosa atrophy was highly associated with cellular senescence. H pylori promoted gastric epithelial cell senescence in vitro and in vivo in a manner that depended on C-X-C motif chemokine receptor 2 (CXCR2) signaling. Interestingly, H pylori infection not only up-regulated the expression of CXCR2 ligands, C-X-C motif chemokine ligands 1 and 8, but also transcriptionally up-regulated the expression of CXCR2 via the nuclear factor-κB subunit 1 directly. In addition, CXCR2 formed a positive feedback loop with p53 to continually enhance senescence. Pharmaceutical inhibition of CXCR2 in an H pylori-infected mouse model attenuated mucosal senescence and atrophy, and delayed further precancerous lesion progression. CONCLUSIONS: Our study showed a new mechanism of H pylori-induced atrophic gastritis through CXCR2-mediated cellular senescence. Inhibition of CXCR2 signaling is suggested as a potential preventive therapy for targeting H pylori-induced atrophic gastritis. GEO data set accession numbers: GSE47797 and GSE3556.

Autoantibodies Toward ATP4A and ATP4B Subunits of Gastric Proton Pump H+,K+-ATPase Are Reliable Serological Pre-endoscopic Markers of Corpus Atrophic Gastritis.

INTRODUCTION: Noninvasive assessment of corpus atrophic gastritis (CAG), a condition at increased risk of gastric cancer, is based on the measurement of pepsinogens, gastrin, and Helicobacter pylori antibodies. Parietal cell autoantibodies (PCAs) against the gastric proton pump (ATP4) are potential serological biomarkers of CAG. The purpose of this study was to compare the diagnostic performance of PCA and pepsinogen I tests in patients with clinical suspicion of CAG with the histopathological evaluation of gastric biopsies as reference standard. METHODS: A prospective case-finding study was performed on 218 naive adult patients (131 women, median age 65 years) who underwent gastric biopsies to confirm/exclude CAG. Patients with histopathological CAG were defined as cases, conversely as controls. Autoantibodies against the individual alpha (ATP4A) and beta (ATP4B) subunits of ATP4 were measured by luciferase immunoprecipitation, and global PCA and pepsinogen I by enzyme-linked immunosorbent assay. RESULTS: Histopathology classified 107 subjects (49%) as cases (CAG+, autoimmune 81.2%, and multifocal extensive 18.8%) and 111 subjects (51%) as controls (CAG-). In cases, ATP4A, ATP4B, and PCA titers were increased compared with controls, whereas pepsinogen I was reduced (P < 0.0001 for all). ATP4B, ATP4A, and pepsinogen I tests showed sensitivities of 77%, 75%, and 73% and specificities of 88%, 88%, and 80%, respectively. The receiver operating characteristic (ROC) area under the ROC curve (AUC) of these serological biomarkers confirmed their ability to discriminate cases from controls (ATP4B = 0.838, ATP4A = 0.826, pepsinogen I = 0.775, and PCA = 0.805), whereas the partial ROC-pAUC90 analysis showed that the ATP4B test had the best diagnostic performance (P = 0.008 vs ATP4; P = 0.0002 vs pepsinogen I). The presence of autoimmune or extensive gastritis was not significantly different between ATP4B positive or negative cases (P = 0.217). DISCUSSION: PCAs are promising serological biomarkers for the identification of CAG in high-risk individuals, particularly in an autoimmune pattern but also in an extensive-multifocal atrophy pattern.

Low Pepsinogen I/II Ratio and High Gastrin-17 Levels Typify Chronic Atrophic Autoimmune Gastritis Patients With Gastric Neuroendocrine Tumors.

INTRODUCTION: Chronic atrophic autoimmune gastritis (CAAG) can lead to the development of gastric neuroendocrine tumors (gNETs) and can be accompanied by other autoimmune diseases. This study aimed to determine, in CAAG patients, the association of gNET development, the prevalence of autoimmune diseases other than CAAG, the association of autoimmunity, and gNET development with pepsinogen I, II, gastrin-17, and Helicobacter pylori infection analysis. METHODS: We determined the prevalence of gNETs and other autoimmune diseases and analyzed pepsinogen I and II, gastrin-17 serum levels, and H. pylori infection in all patients diagnosed with CAAG at our hospital between 2013 and 2017. RESULTS: A total of 156 patients were studied and in 15.4% was observed concomitant gNET. Approximately 68.6% had at least 1 other autoimmune disease at diagnosis of CAAG. Approximately 60.9% had autoimmune thyroiditis, followed by diabetes (19.9%) and autoimmune polyendocrine syndrome (12.8%). CAAG patients with and without gNET had similar rates of comorbidity with other autoimmune diseases, but the pepsinogen I/II ratio was lower in patients with gNET (1.6 vs 4.5, P = 0.018). Receiver operating characteristic curve analyses identified a pepsinogen I/II ratio <2.3 and gastrin-17 levels >29.6 pmol/L as cutoffs distinguishing CAAG patients with gNET from those without. The combined use of these cutoff correctly identified 16 of the 18 CAAG patients with gNET (P = 0.007). H. pylori infection was observed in 28.7% of cases tested but did not associate with gNET. DISCUSSION: This study suggests that a low pepsinogen I/II ratio and high gastrin-17 levels characterize patients with CAAG and gNET and confirms the frequent coexistence of CAAG with other autoimmune diseases.

Single-Cell Transcriptional Analyses Identify Lineage-Specific Epithelial Responses to Inflammation and Metaplastic Development in the Gastric Corpus.

BACKGROUND & AIMS: Chronic atrophic gastritis can lead to gastric metaplasia and increase risk of gastric adenocarcinoma. Metaplasia is a precancerous lesion associated with an increased risk for carcinogenesis, but the mechanism(s) by which inflammation induces metaplasia are poorly understood. We investigated transcriptional programs in mucous neck cells and chief cells as they progress to metaplasia mice with chronic gastritis. METHODS: We analyzed previously generated single-cell RNA-sequencing (scRNA-seq) data of gastric corpus epithelium to define transcriptomes of individual epithelial cells from healthy BALB/c mice (controls) and TxA23 mice, which have chronically inflamed stomachs with metaplasia. Chronic gastritis was induced in B6 mice by Helicobacter pylori infection. Gastric tissues from mice and human patients were analyzed by immunofluorescence to verify findings at the protein level. Pseudotime trajectory analysis of scRNA-seq data was used to predict differentiation of normal gastric epithelium to metaplastic epithelium in chronically inflamed stomachs. RESULTS: Analyses of gastric epithelial transcriptomes revealed that gastrokine 3 (Gkn3) mRNA is a specific marker of mouse gastric corpus metaplasia (spasmolytic polypeptide expressing metaplasia, SPEM). Gkn3 mRNA was undetectable in healthy gastric corpus; its expression in chronically inflamed stomachs (from TxA23 mice and mice with Helicobacter pylori infection) identified more metaplastic cells throughout the corpus than previously recognized. Staining of healthy and diseased human gastric tissue samples paralleled these results. Although mucous neck cells and chief cells from healthy stomachs each had distinct transcriptomes, in chronically inflamed stomachs, these cells had distinct transcription patterns that converged upon a pre-metaplastic pattern, which lacked the metaplasia-associated transcripts. Finally, pseudotime trajectory analysis confirmed the convergence of mucous neck cells and chief cells into a pre-metaplastic phenotype that ultimately progressed to metaplasia. CONCLUSIONS: In analyses of tissues from chronically inflamed stomachs of mice and humans, we expanded the definition of gastric metaplasia to include Gkn3 mRNA and GKN3-positive cells in the corpus, allowing a more accurate assessment of SPEM. Under conditions of chronic inflammation, chief cells and mucous neck cells are plastic and converge into a pre-metaplastic cell type that progresses to metaplasia.

Analysis of clinical characteristics of 2243 with positive anti-gastric parietal cell antibody.

BACKGROUND: To facilitate the early detection of chronic diseases, we analyzed the clinical characteristics of anti-gastric parietal cell antibody (PCA)-positive population, revealed the early characteristics of the population. METHODS: According to the retrospective analysis, current situation investigation and comparative analysis of the clinical characteristics and medical history of the subjects, the comparison between the groups was performed. RESULT: (a) The positive rate of PCA detection in department of gastroenterology in our hospital was 35.80%. Among the individuals who underwent PCA, esophagogastroduodenoscopy (EGD) and pathological examination at the same time, 33.59% of the patients with PCA positive were diagnosed as atrophic gastritis by gastroscopy, which was much higher than 9.09% of the patients with PCA negative. (b) The incidence of gastroesophageal reflux, hypertension, ischemic heart disease (IHD) and cerebral ischemia in PCA-positive population were 65.45%, 81.63%, 15.43%, and 31.61%, respectively, which were significantly higher than those in the control group. (c) The incidence rates of decreased red blood cells (RBC) and increased homocysteine (HCY) in laboratory-related tests were 38.30% and 69.15%, respectively, which were much higher than those in control group. CONCLUSION: PCA has predictive value for a variety of chronic diseases and timely detection is of great significance.

Mechanism of berberine in treating Helicobacter pylori induced chronic atrophic gastritis through IRF8-IFN-γ signaling axis suppressing.

AIMS: In this study, we will investigate the therapeutic effects of berberine (BBR) in Helicobacter pylori (H. pylori) induced chronic atrophic gastritis (CAG). Furthermore, potential mechanisms of BBR in regulating IRF8-IFN-γ signaling axis will also be investigated. MATERIALS AND METHODS: H. pylori were utilized to establish CAG model of rats. Therapeutic effects of BBR on serum supernatant indices, and histopathology of stomach were analyzed in vivo. Moreover, GES-1 cells were infected by H. pylori, and intervened with BBR in vitro. Cell viability, morphology, proliferation, and quantitative analysis were detected by high-content screening (HCS) imaging assay. To further investigate the potential mechanisms of BBR, relative mRNA, immunohistochemistry and protein expression in IRF8-IFN-γ signaling axis were measured. KEY FINDINGS: Results showed serum supernatant indices including IL-17, CXCL1, and CXCL9 were downregulated by BBR intervention, while, G-17 increased significantly. Histological injuries of gastric mucosa induced by H. pylori also were alleviated. Moreover, cell viability and morphology changes of GES-1 cells were improved by BBR intervention. In addition, proinflammatory genes and IRF8-IFN-γ signaling axis related genes, including Ifit3, Upp1, USP18, Nlrc5, were suppressed by BBR administration in vitro and in vivo. The proteins expression related to IRF8-IFN-γ signaling axis, including Ifit3, IRF1 and Ifit1 were downregulated by BBR intervention.

[Chronic autoimmune gastritis : a multidisciplinary management]. / La gastrite chronique auto-immune : une prise en charge multidisciplinaire.

Chronic autoimmune gastritis (CAG) is a continuum of histological changes in gastric mucosa including: atrophy, intestinal metaplasia, dysplasia and finally, the occurrence of a neoplasm (gastric Neuroendocrine Tumors -NETs- and adenocarcinoma). The association with Hashimoto and Graves-Basedow disease is known as the thyrogastric autoimmune syndrome. While Helicobacter pylori (Hp) infection may be associated with CAG, the role of the gastric microbiota is ill-defined. The gastric hypochlorhydria determines a malabsorption of different micronutrients (iron, magnesium, calcium, vitamin B12) as well as drugs (thyroxine, etc.). Pernicious anemia is favoured by the deficit of parietal intrinsic factor that contributes to B12 malabsorption. Serology for Hp, serum pepsinogen I/II, increased gastrin levels, the presence of parietal cell antibodies and intrinsic factor antibodies may reveal CAG. High definition endoscopy associated with virtual chromoendoscopy seems promising for CAG diagnosis and follow-up. NETs type 1 treatment includes: endoscopic and surgical resection, somatostatin analogues and the recent availability of netazepide, a gastrin antagonist. We review herein advances in the treatment and diagnosis of CAG and associated autoimmune disorders, which may involve, in a multidisciplinary way, all practitioners.

La gastrite chronique auto-immune (GAI) est un continuum d'altérations de la muqueuse gastrique incluant : atrophie, métaplasie intestinale, dysplasie et, enfin, la survenue d'une néoplasie (tumeurs neuroendocrines [NETs] gastriques et adénocarcinome). L'association avec la maladie de Hashimoto et de Graves-Basedow est connue comme syndrome thyrogastrique auto-immun. Alors que l'Helicobacter pylori (Hp) peut s'associer avec la GAI, le rôle du microbiote gastrique est mal défini. L'hypochlorhydrie gastrique détermine une malabsorption de micronutriments (fer, magnésium, calcium, vitamine B12) et de médicaments (thyroxine et autres). L'anémie de Biermer est favorisée par le déficit de production du facteur intrinsèque pariétal, contribuant à la malabsorption de B12. Un rapport diminué de pepsinogène I/II, une augmentation de la gastrine, la présence d'anticorps anti-cellule pariétale, les anticorps anti-facteur intrinsèque et la sérologie pour Hp contribuent à révéler précocement le diagnostic de GAI. L'endoscopie haute définition, associée à la chromoendoscopie virtuelle, semble prometteuse dans le diagnostic et dans le suivi. Le traitement des NETs gastriques de type 1, favorisées par la GAI, inclut : la résection endoscopique/chirurgicale, les analogues de la somatostatine et l'antagoniste de la gastrine nétazépide. Nous résumons ici les avancées diagnostiques et thérapeutiques dans la GAI et dans les affections associées : elles impliquent, de façon multidisciplinaire, l'ensemble des praticiens.

Subacute Combined Degeneration of the Spinal Cord and Hydrocephalus Associated with Vitamin B12 Deficiency.

BACKGROUND: This study aimed to report the case of a patient who presented with depression, cognitive impairment, ataxic gait, and urinary incontinence associated with vitamin B12 deficiency. CASE DESCRIPTION: Serum vitamin B12 level was low in this patient, and anti-intrinsic factor antibody was positive. Neuroimaging revealed abnormal hyperintense signals in the cerebellum and dorsal and lateral columns of the spinal cord, and obstructive hydrocephalus. A biopsy of the stomach revealed chronic gastritis, intestinal metaplasia, and atrophy. After 3 months of initiating methylcobalamin therapy, significant improvement was noticed clinically, and brain magnetic resonance imaging was near to normal. CONCLUSIONS: This study was novel in reporting subacute combined degeneration of the spinal cord and hydrocephalus associated with vitamin B12 deficiency in adults.

Prevalence and determinants of serological evidence of atrophic gastritis among Arab and Jewish residents of Jerusalem: a cross-sectional study.

OBJECTIVE: Understanding the correlates of premalignant gastric lesions is essential for gastric cancer prevention. We examined the prevalence and correlates of serological evidence of atrophic gastritis, a premalignant gastric condition, using serum pepsinogens (PGs) in two populations with differing trends in gastric cancer incidence. METHODS: In a cross-sectional study, using ELISA we measured serum PGI and PGII concentrations (Biohit, Finland), Helicobacter pylori serum IgG and cytotoxin-associated gene A (CagA) antigen IgG antibodies in archived sera of 692 Jews and 952 Arabs aged 25-78 years, randomly selected from Israel's population registry in age-sex and population strata. Multivariable logistic regression analyses were performed. RESULTS: Using cut-offs of PGI <30µg/L or PGI:PGII <3.0, the prevalence of atrophic gastritis was higher among Arab than Jewish participants: 8.8% (95% CIs 7.2% to 10.8%) vs 5.9% (95% CI 4.4% to 7.9%), increasing with age in both groups (p<0.001 for trend). Among Jewish participants, infection with H. pylori CagA phenotype was positively related to atrophic gastritis: adjusted OR (aOR) 2.16 (95% CI 0.94 to 4.97), but not to non-CagA infections aOR 1.17 (95% CI 0.53 to 2.55). The opposite was found among Arabs: aOR 0.09 (95% CI 0.03 to 0.24) for CagA positive and aOR 0.15 (95% CI 0.06 to 0.41) for Cag A negative phenotypes (p<0.001 for interaction). Women had a higher atrophic gastritis prevalence than men. Obesity and smoking were not significantly related to atrophic gastritis; physical activity tended to be inversely associated in Arabs (p=0.08 for interaction). CONCLUSIONS: The prevalence of atrophic gastritis was higher among Arabs than Jews and was differently associated with the CagA phenotype.

Nuclear magnetic resonance-based metabolomics approach to evaluate preventive and therapeutic effects of Gastrodia elata Blume on chronic atrophic gastritis.

Chronic atrophic gastritis (CAG) is one of the most common digestive system diseases worldwide which defined by WHO as initial step of cancer. Gastrodia elata Blume (GEB) is a traditional herbal with multiple pharmacological activities which was widely used in Asian countries. This study aims to explore the preventive and therapeutical effects of Gastrodia elata Blume on auto-immune induced CAG in rats. Tissues of stomachs were collected and submitted to 1H NMR-based metabolomics analysis and histopathological inspection. The biochemical indexes of MDA, SOD, GSH, NO and XOD were measured. Gastrodia elata Blume could apparently ameliorate the damaged gastric glands and the biochemical parameters, enhance gastric acid secretion, and significantly relieve the inflammation of the stomach. Orthogonal signal correction-partial least squares-discriminant analysis (OSC-PLS-DA) of NMR profiles and correlation network analysis revealed that Gastrodia elata Blume could effectively treat CAG via regulating energy and purine metabolisms, and by anti-oxidation and anti-inflammation effects.

Gastritis autoinmune: diagnóstico y manejo de una entidad subdiagnosticada / Autoimmune gastritis: diagnosis and management of an underdiagnosed disease

Autoimmune gastritis (AIG) or chronic atrophic gastritis type A, is a chronic inflammatory disease that affects the body and fundus mucosa of the stomach. It is an underdiagnosed entity, whose clinical presentation has a broad spectrum, which may include asymptomatic patients; hematological manifestations such as iron deficiency anemia, vitamin B12 deficiency anemia (so called pernicious); non-specific digestive symptoms like dyspepsia; neurological and psychiatric manifestations. AIG is associated with other autoimmune diseases, mainly hypothyroidism ("Tyrogastric Syndrome") and type 1 diabetes. It is characterized by the development of anti-parietal cell and anti-intrinsic factor antibodies, decrease in pepsinogen I (PGI) level with low PGI/PGII ratio (< 3), and high level of gastrin. Endoscopic findings are not sufficient for the diagnosis of gastric atrophy. The use of the Sydney pathological report protocol and the OLGA/OLGIM system to evaluate the severity of gastritis have improved their diagnosis and the possibility to establish the risk of developing gastric neoplasms. The importance of its diagnosis and surveillance is based on the development of type 1 neuroendocrine gastric neoplasms, in addition to an increased risk of the incidence of gastric adenocarcinoma. Currently, an individualized endoscopic surveillance seems reasonable, with a minimum interval of 3 years.

La gastritis autoinmune (GAI) o gastritis crónica atrófica tipo A, es una enfermedad inflamatoria crónica que afecta la mucosa del cuerpo y fondo del estómago. La GAI es una entidad subdiagnosticada, cuya presentación clínica es de amplio espectro, puede incluir pacientes asintomáticos; manifestaciones hematológicas, tales como anemia ferropriva, anemia por déficit de vitamina B12 (anemia perniciosa); digestivas inespecíficas tipo dispepsia; neurológicas y psiquiátricas. La GAI está asociada a otras enfermedades autoinmunes, principalmente hipotiroidismo ("síndrome tirogástrico") y diabetes tipo 1. Se caracteriza por el desarrollo de anticuerpos anti células parietales y anti factor intrínseco, bajo nivel de pepsinógeno I (PGI) con una baja relación PGI/PGII (< 3), e hipergastrinemia. Los hallazgos endoscópicos no son suficientes para el diagnóstico de atrofia gástrica. El uso de protocolo de Sydney de reporte patológico y sistema OLGA/OLGIM para evaluar la severidad de gastritis han mejorado su diagnóstico y objetivado su riesgo de desarrollar neoplasias gástricas. La importancia de su diagnóstico y seguimiento está basada en el desarrollo de neoplasias gástricas neuroendocrinas tipo 1, además de un riesgo incrementado de la incidencia de adenocarcinoma gástrico, entre otros. Actualmente, parece razonable un seguimiento endoscópico individualizado, siendo un intervalo mínimo de 3 años.

Chronic Atrophic Gastritis: A Review.

Chronic atrophic gastritis is a generally asymptomatic condition of great importance because it develops into gastric cancer in a number of patients. It is described as an atrophy of the gastric mucosa. There are two types of atrophic gastritis: a gastric body predominant type in patients with infection of Helicobacter pylori, and an autoimmune type, limited to the gastric body and fundus. The autoimmune type is quite rare and affects people of all ethnicities. Globally, H. pylori infection is very common and is considered a class I carcinogen due to the large number of patients who subsequently develop gastric cancer. The pathogenesis of the autoimmune type involves an antibody-mediated loss of parietal cells resulting in achlorhydria and an antibody-mediated loss of intrinsic factor that causes pernicious anemia. The diagnosis of H. pylori infection is based on endoscopy and culture of the organisms. Patients with atrophic gastritis as well as H. pylori infection should be treated with antibiotics to eradicate the organism. Patients with the autoimmune type need to be evaluated for anemia, and if present, treated with vitamin B12.

Comparison of the human gastric microbiota in hypochlorhydric states arising as a result of Helicobacter pylori-induced atrophic gastritis, autoimmune atrophic gastritis and proton pump inhibitor use.

Several conditions associated with reduced gastric acid secretion confer an altered risk of developing a gastric malignancy. Helicobacter pylori-induced atrophic gastritis predisposes to gastric adenocarcinoma, autoimmune atrophic gastritis is a precursor of type I gastric neuroendocrine tumours, whereas proton pump inhibitor (PPI) use does not affect stomach cancer risk. We hypothesised that each of these conditions was associated with specific alterations in the gastric microbiota and that this influenced subsequent tumour risk. 95 patients (in groups representing normal stomach, PPI treated, H. pylori gastritis, H. pylori-induced atrophic gastritis and autoimmune atrophic gastritis) were selected from a cohort of 1400. RNA extracted from gastric corpus biopsies was analysed using 16S rRNA sequencing (MiSeq). Samples from normal stomachs and patients treated with PPIs demonstrated similarly high microbial diversity. Patients with autoimmune atrophic gastritis also exhibited relatively high microbial diversity, but with samples dominated by Streptococcus. H. pylori colonisation was associated with decreased microbial diversity and reduced complexity of co-occurrence networks. H. pylori-induced atrophic gastritis resulted in lower bacterial abundances and diversity, whereas autoimmune atrophic gastritis resulted in greater bacterial abundance and equally high diversity compared to normal stomachs. Pathway analysis suggested that glucose-6-phospahte1-dehydrogenase and D-lactate dehydrogenase were over represented in H. pylori-induced atrophic gastritis versus autoimmune atrophic gastritis, and that both these groups showed increases in fumarate reductase. Autoimmune and H. pylori-induced atrophic gastritis were associated with different gastric microbial profiles. PPI treated patients showed relatively few alterations in the gastric microbiota compared to healthy subjects.

BREG cells in Hashimoto's thyroiditis isolated or associated to further organ-specific autoimmune diseases.

Hashimoto thyroiditis (HT) may occur isolated or associated with other non-endocrine autoimmune disorders (NEAD). No data are available about Breg cells in these disorders and this represented the aim of the study. Th17 and Breg cells subset were characterized on peripheral blood mononuclear cells isolated from 18 healthy donors (HD), 19 patients with isolated HT and 26 patients with HT+NEAD. Th17 were higher in patients with isolated HT than in HD but no further changes were seen in patients with HT+NEAD. CD24hiCD38hi unstimulated Breg cells were similar in HT patients and in HD, but significantly higher in patients with HT+NEAD than in both HT and in HD. CD19+CD24hiCD27+ Breg memory phenotype was similar in HD and in HT patients, but decreased in patients with HT+NEAD (23.4%vs38.5%). Upon CpG-stimulation, CD24hiCD38hi IL-10+ Breg cells were higher in HT patients than in HD (3.9%vs1.8%) but similar in patients with HT+NEAD (2.4%).

Autoimmune metaplastic atrophic gastritis in chinese: a study of 320 patients at a large tertiary medical center.

OBJECTIVES: Autoimmune metaplastic atrophic gastritis (AMAG) is an uncommon disease worldwide and may predispose to gastric carcinoid tumors or adenocarcinomas. The aims of this study were to outline the clinical characteristics of Chinese AMAG patients, including demographic pattern, hematologic features, and gastroscopic and histopathologic findings. PATIENTS AND METHODS: A total of 320 Chinese patients with AMAG, from January 2007 to December 2014, were reviewed in a regional hospital of China. RESULTS: Of the 320 AMAG patients, the mean age was 60.6 ± 12.3 years [range 26-86; 206 (64.4%) women]. The coarse annual detection rate was 0.9%. Anemia was present in only 19.3% patients (53/275) and 3.5% (11/315) AMAG patients also had primary biliary cirrhosis. One hundred and thirty-six had endoscopically identifiable lesions. These lesions consisted of 130 polypoid lesions (63 hyperplastic polyps, 2 oxyntic mucosa pseudopolyps, 2 intestinal-type gastric adenomas, 2 fundic gland polyps, 5 concurrent polyps, 14 well-differentiated neuroendocrine neoplasms, 7 submucosal tumors and 35 chronic gastritis), 6 adenocarcinomas. The detection rate of atrophy and intestinal metaplasia in antral mucosa were 47.2 and 37.5%, respectively. CONCLUSIONS: AMAG is more frequent than expected in China and display a female predominance, accompanied with other autoimmune disorders. AMAG should be paid more attention by clinicians through a multidisciplinary team approach.

Impact of Helicobacter pylori Immunoglobulin G Levels and Atrophic Gastritis Status on Risk of Metabolic Syndrome.

BACKGROUND: Helicobacter pylori (HP) infection is implicated in gastric and extra-gastric diseases. While gastritis-related chronic inflammation represents a known trigger of metabolic disturbances, whether metabolic syndrome (MetS) is affected by gastritis status remains unclear. We aimed to clarify the effect of HP-related gastritis on the risk of MetS. MATERIALS AND METHODS: We retrospectively enrolled patients undergoing screening for MetS between 2014 and 2015. Investigations included HP-specific immunoglobulin G (IgG) antibody assays to detect HP infection, and serum pepsinogen assays to evaluate atrophic gastritis status. The risk of MetS was evaluated via multiple logistic regression analyses with two covariates: serum HP infection status (IgG levels) and atrophic gastritis status (two criteria were applied; pepsinogen I/II ratio < 3 or both pepsinogen I levels ≤ 70 µg/L and pepsinogen I/II ratio < 3). RESULTS: Of 1,044 participants, 247 (23.7%) were HP seropositive, and 62 (6.0%) had MetS. HP seronegative and seropositive patients had similar risks of MetS. On the other hand, AG (defined in terms of serum PG I/II <3) was significant risk of MetS (OR of 2.52 [95% CI 1.05-7.52]). After stratification according to HP IgG concentration, patients with low HP infection status had the lowest MetS risk (defined as an odds ratio [OR] adjusted for age, sex, smoking, drinking and physical activity status). Taking this result as a reference, patients with negative, moderate, and high HP infection status had ORs (with 95% confidence intervals [CI]) of 2.15 (1.06-4.16), 3.69 (1.12-16.7), and 4.05 (1.05-26.8). CONCLUSIONS: HP-associated gastritis represents a risk factor for MetS. Research should determine why low and not negative HP infection status is associated with the lowest MetS risk.

Autoimmune gastritis.

Autoimmune gastritis is a chronic inflammatory disease with destruction of parietal cells of the corpus and fundus of the stomach. The known consequence is vitamin B12 deficiency and, consequently, pernicious anemia. However, loss of parietal cells reduces secretion of gastric acid which is also required for absorption of inorganic iron; thus, iron deficiency is commonly found in patients with autoimmune gastritis. This usually precedes vitamin B12 deficiency and is found mainly in young women. Patients with chronic iron deficiency, especially those refractory to oral iron therapy, should therefore be evaluated for the presence of autoimmune gastritis.