Deleterious effect of Helicobacter pylori infection on the course of acute pancreatitis in rats

Cornu aspersum mucin attenuates indomethacins-induced gastric ulcers in mice via alleviating oxidative stress and inflammation

In the past three decades, a significant progress has been made in the prevention and treatment of gastric ulcers. The incidence of the disease has decreased, but gastric ulcer is still a medical problem. Currently, the available drugs for gastric ulcer treatment have many side effects; therefore, searching for new and safe therapeutic agents is mandatory. The present study aims to investigate the gastroprotective potential of Cornu aspersum (C. aspersum) mucin against gastric ulcers, and the mechanisms related to oxidative stress and inflammation. C. aspersum mucin was collected from 50 snails. The characteristics of C. aspersum mucin (chemical and microbiological) were evaluated. Mice were pretreated with famotidine and C. aspersum mucin (7.5 and 15 ml/kg b.w.) for 5 days, and then gastric ulcers were induced by indomethacin. Macroscopic examination, biochemical estimations, and Quantitative real-time PCR were carried out. Also, histopathological and immunohistopathological examinations were evaluated. We found that the high dose of the mucin significantly decreased the gastric mucosal malondialdehyde (MDA) and nitric oxide (NO) contents as well as interleukin 1β (IL-1β) and nuclear factor kappa β (NF-ҡB) expression, and inducible nitric oxide synthase (iNOS) immunostaining. It also increased the gastric mucosal GSH and catalase contents as well as hemoxygenase-1 (HO-1) and nuclear factor-erythroid 2-related factor 2 (Nrf2) expressions with regressions in gastric mucosal lesions. In conclusion, C. aspersum mucin could be a potential therapeutic candidate to protect against gastric ulceration.

Helicobacter Species and Hepato-Biliary Tract Malignancies: A Systematic Review and Meta-Analysis

Helicobacter species may cause chronic inflammation of the biliary tract, but its relationship with cancer is controversial. We performed a systematic review and meta-analysis to evaluate the association between Helicobacter species and hepatobiliary tract malignancies. Twenty-six studies (4083 patients) were included in qualitative synthesis, and 18 studies (n = 1895 qualified for meta-analysis. All studies were at high-intermediate risk of bias. Most studies combined several direct microbiological methods, mostly PCR (23 studies), culture (8 studies), and/or CLOtest (5 studies). Different specimens alone or in combination were investigated, most frequently bile (16 studies), serum (7 studies), liver/biliary tissue (8 studies), and gastric tissue (3 studies). Patients with Helicobacter species infection had an increased risk of hepatobiliary tract malignancies (OR = 3.61 [95% CI 2.18-6.00]; p < 0.0001), with high heterogeneity in the analysis (I2 = 61%; p = 0.0003). This effect was consistent when Helicobacter was assessed in bile (OR = 3.57 [95% CI 1.73-7.39]; p = 0.0006), gastric tissue (OR = 42.63 [95% CI 5.25-346.24]; p = 0.0004), liver/biliary tissue (OR = 4.92 [95% CI 1.90-12.76]; p = 0.001) and serum (OR = 1.38 [95% CI 1.00-1.90]; p = 0.05). Heterogeneity was reduced in these sub-analyses (I2 = 0-27%; p = ns), except for liver/biliary tissue (I2 = 57%; p = 0.02). In conclusion, based on low-certainty data, Helicobacter species chronic infection is associated with a tripled risk of hepatobiliary tract malignancy. Prospective studies are required to delineate public health interventions.

Effect of Helicobacter pylori infection on prognosis of severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis progresses rapidly and has a high fatality rate. How to delay its progression and improve its prognosis is a major medical problem at present. In recent years, a number of studies have found that Helicobacter pylori (H. pylori) infection affects the occurrence and development of acute pancreatitis, but there are still few studies on whether it affects the prognosis of patients with severe acute pancreatitis.

AIM

To investigate the effect of H. pylori infection on the prognosis of severe acute pancreatitis.

METHODS

Patients with severe acute pancreatitis were divided into either an H. pylori infection group (group A) or a no H. pylori infection group (group B) according to the presence of H. pylori antigen or not. Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ), bedside index for severity in acute pancreatitis (BISAP), and modified CT severity index (MCTSI) were recorded and compared between the two groups at admission, 96 h after admission, and 2 wk after admission. The incidence of pancreatic infection, length of intensive care unit (ICU) stay, and total length of stay were also compared between the two groups.

RESULTS

APACHE Ⅱ, BISAP, and MCTSI scores were higher in group A than in group B at 2 wk after admission. ICU stay and total length of stay in group A were significantly longer than those in group B.

CONCLUSION

H. pylori infection may be one of the factors leading to the progression of severe acute pancreatitis.

Pre-Treatment with Grape Seed Extract Reduces Inflammatory Response and Oxidative Stress Induced by Helicobacter pylori Infection in Human Gastric Epithelial Cells

Helicobacter pylori (H. pylori) is a pathogenic bacteria identified as a potential risk factor for gastritis, gastric ulcers and gastric cancer. During the stomach colonization, H. pylori triggers a strong inflammatory response and subsequent oxidative stress, which are associated with tissue damage. For this reason, it is of particular interest to develop alternative natural tools that enable modulation of the associated damaging immune response. With this purpose, we obtained grape seed extract (GSE) from sweet (not fermented) food grade seeds. The aim of our study was to investigate the effect of GSE and its two enriched procyanidins fractions (OPC and PPC) on the inflammatory process and oxidative stress produced by different H. pylori strains in human gastric epithelial cells (AGS). Anti-inflammatory activity was evaluated by measuring the level of interleukin-8 (IL-8) secretion. IL-8 production was significantly reduced in H. pylori-infected human gastric epithelial cells pre-treated with GSE or its enriched fractions when compared with non-pre-treated infected cells (from 21.6% to 87.8%). Pre-treatment with GSE or its fractions significantly decreased intracellular reactive oxygen species (ROS) production in AGS cells after infection, depending on the H. pylori strain. Our results also showed that GSE and its fractions demonstrate antibacterial activity against all strains of H. pylori used in the study. This work demonstrates the effectiveness of GSE enriched in procyanidins against the main events associated with H. pylori infection.

Distinct Microbiota Dysbiosis in Patients with Non-Erosive Reflux Disease and Esophageal Adenocarcinoma

Non-erosive reflux disease (NERD) and esophageal adenocarcinoma (EAC) are often regarded as bookends in the gastroesophageal reflux disease spectrum. However, there is limited clinical evidence to support this disease paradigm while the underlying mechanisms of disease progression remain unclear. In this study, we used 16S rRNA sequencing and mass-spectrometer-based proteomics to characterize the esophageal microbiota and host mucosa proteome, respectively. A total of 70 participants from four patient groups (NERD, reflux esophagitis, Barrett’s esophagus, and EAC) and a control group were analyzed. Our results showed a unique NERD microbiota composition, distinct to control and other groups. We speculate that an increase in sulfate-reducing Proteobacteria and Bacteroidetes along with hydrogen producer Dorea are associated with a mechanistic role in visceral hypersensitivity. We also observed a distinct EAC microbiota consisting of a high abundance of lactic acid-producing bacteria (Staphylococcus, Lactobacillus, Bifidobacterium, and Streptococcus), which may contribute towards carcinogenesis through dysregulated lactate metabolism. This study suggests the close relationship between esophageal mucosal microbiota and the appearance of pathologies of this organ.

Linking gut microbiota with the human diseases

The human gut is rich in microbes. Therefore, it is of interest to document data to link known human diseases with the gut microbiota. Various factors like hormones, metabolites and dietary habitats are responsible for shaping the microbiota of the gut. Imbalance in the gut microbiota is responsible for the pathogenesis of various disease types including rheumatoid arthritis, different types of cancer, diabetes mellitus, obesity, and cardiovascular disease. We report a review of known data for the correction of dysbiosis (imbalance in microbe population) towards improved human health.

Anti-Inflammatory and Antioxidant Activities of Medicinal Plants Used by Traditional Healers for Antiulcer Treatment

For centuries, many kinds of native plants and their products have been used for the treatment of gastric ulcers by traditional healers in Phayao province. The current study aimed to investigate the polyphenol content in some of these medicinal plants and to point out the relationship between their antioxidant capacity and anti-inflammatory activities. Six species were selected based on ethnopharmacologic considerations: Punica granatum L., Psidium guajava L., Careya arborea Roxb., Gochnatia decora (Kurz) Cabr., Shorea obtusa Wall. ex Blume, and Ficus hispida L.f. The leaves or bark of these plants were extracted with 70% ethanol and water. Anti-inflammatory and antioxidant activities of the extracts were analyzed based on nitric oxide (NO) and proinflammatory cytokine production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and through the determination of scavenging activity. The results demonstrated that the ethanol extract from P. granatum and P. guajava leaves significantly inhibited NO production by suppressing nitric oxide synthase. The extracts also inhibited tumor necrosis factor-α, interleukin-1, and interleukin-6 in terms of both mRNA and protein levels and possessed high antioxidants. These extracts were shown to contain the highest amount of polyphenols. Our study concluded that among the plants studied, P. granatum and P. guajava have the most significant anti-inflammatory and antioxidant activities and polyphenols. These plants may have the potential for use in gastric ulcer therapy due to their indicated properties. Future research should focus on the isolation of their active compounds and their in vivo biological activities. Their beneficial applications need to be warranted by such evidence.

Microbiome-Gut-Brain Axis and Toll-Like Receptors in Parkinson's Disease

Parkinson’s disease (PD) is a progressively debilitating neurodegenerative disease characterized by α-synucleinopathy, which involves all districts of the brain-gut axis, including the central, autonomic and enteric nervous systems. The highly bidirectional communication between the brain and the gut is markedly influenced by the microbiome through integrated immunological, neuroendocrine and neurological processes. The gut microbiota and its relevant metabolites interact with the host via a series of biochemical and functional inputs, thereby affecting host homeostasis and health. Indeed, a dysregulated microbiota-gut-brain axis in PD might lie at the basis of gastrointestinal dysfunctions which predominantly emerge many years prior to the diagnosis, corroborating the theory that the pathological process is spread from the gut to the brain. Toll-like receptors (TLRs) play a crucial role in innate immunity by recognizing conserved motifs primarily found in microorganisms and a dysregulation in their signaling may be implicated in α-synucleinopathy, such as PD. An overstimulation of the innate immune system due to gut dysbiosis and/or small intestinal bacterial overgrowth, together with higher intestinal barrier permeability, may provoke local and systemic inflammation as well as enteric neuroglial activation, ultimately triggering the development of alpha-synuclein pathology. In this review, we provide the current knowledge regarding the relationship between the microbiota-gut⁻brain axis and TLRs in PD. A better understanding of the dialogue sustained by the microbiota-gut-brain axis and innate immunity via TLR signaling should bring interesting insights in the pathophysiology of PD and provide novel dietary and/or therapeutic measures aimed at shaping the gut microbiota composition, improving the intestinal epithelial barrier function and balancing the innate immune response in PD patients, in order to influence the early phases of the following neurodegenerative cascade.

Association between Peptic Ulcer Disease and Periodontitis: A Nationwide Population-Based Case-Control Study in Taiwan

Previous studies have suggested that peptic ulcer disease (PUD) including stomach and duodenal ulcers might be associated with periodontitis (PD); however, no clear conclusions have been reached thus far. In this retrospective case-control study, we aimed to investigate the association between PUD and PD by using a large population-based dataset in Taiwan. A population-based retrospective case control study was conducted using the Longitudinal Health Insurance Database 2010 (LHID2010) derived from the National Health Insurance Research database (NHIRD) in Taiwan from 2000 to 2013. The case and control group were matched with gender, age, urbanization level, socioeconomic status, and Charlson comorbidity index (CCI) by using the propensity score method at a 1:1 ratio. A total of 177,240 cases and 177,240 control patients were included in this study, with an average age of 46.96 ± 11.76 years. The risk of PUD for patients diagnosed with PD was 1.15-fold when compared with those without PD (OR, 1.15; 95% CI, 1.12–1.18). This population-based case control study demonstrated a significantly positive association between PUD and PD in Taiwan.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

Effects of Ganoderma lucidum polysaccharides on chronic pancreatitis and intestinal microbiota in mice

This study manifested the effects of polysaccharides from Ganoderma lucidum strain S₃ (GLP S₃) on chronic pancreatitis (CP) therapy and intestinal microbiota modulation in mice induced by diethyldithiocarbamate (DDC). The GLPS₃ was prepared from cultured mycelium and markedly alleviated the pancreatitis in mice through decreasing lipase, AMS, IFN-γ and TNF-α level as well as increasing SOD and total antioxidant activity. Furthermore, high throughput sequencing analysis revealed that GLPS₃ altered the composition and diversity of intestinal microbiota, especially, decreased the relative abundance of phylum Bacteroidetes and increased that of phylum Firmictutes. At the genus level, supplementation of GLPS₃ increased the relative abundance of the beneficial bacteria such as Lactobacillales, Roseburia and Lachnospiraceae. These results disclosed the potential therapy mechanism of GLPS₃ on chronic pancreatitis might be intestinal microbiota dependent.

Extragastric manifestations of Helicobacter pylori infection: Possible role of bacterium in liver and pancreas diseases

Helicobacter pylori (H. pylori) is an ancient microorganism that has co-evolved with humans for over 60000 years. This bacterium typically colonizes the human stomach and it is currently recognized as the most common infectious pathogen of the gastroduodenal tract. Although its chronic infection is associated with gastritis, peptic ulcer, dysplasia, neoplasia, MALT lymphoma and gastric adenocarcinoma, it has been suggested the possible association of H. pylori infection with several extragastric effects including hepatobiliary and pancreatic diseases. Since a microorganism resembling H. pylori was detected in samples from patients with hepatobiliary disorders, several reports have been discussed the possible role of bacteria in hepatic diseases as hepatocellular carcinoma, cirrhosis and hepatic encephalopathy, nonalcoholic fatty liver disease and fibrosis. Additionally, studies have reported the possible association between H. pylori infection and pancreatic diseases, especially because it has been suggested that this infection could change the pancreatic physiology. Some of them have related a possible association between the microorganism and pancreatic cancer. H. pylori infection has also been suggested to play a role in the acute and chronic pancreatitis pathogenesis, autoimmune pancreatitis, diabetes mellitus and metabolic syndrome. Considering that association of H. pylori to liver and pancreas diseases needs further clarification, our work offers a review about the results of some investigations related to the potential pathogenicity of H. pylori in these extragastric diseases.

Helicobacter pylori and pancreatic diseases

A possible role for Helicobacter pylori (H. pylori) infection in pancreatic diseases remains controversial. H. pylori infection with antral predomination leading to an increase in pancreatic bicarbonate output and inducing ductal epithelial cell proliferation could contribute to the development of pancreatic cancer via complex interactions with the ABO genotype, dietary and smoking habits and N-nitrosamine exposure of the host. Although the individual study data available so far is inconsistent, several meta-analyses have reported an increased risk for pancreatic cancer among H. pylori seropositive individuals. It has been suggested that H. pylori causes autoimmune pancreatitis due to molecular mimicry between H. pyloriα-carbonic anhydrase (α-CA) and human CA type II, and between H. pylori plasminogen-binding protein and human ubiquitin-protein ligase E3 component n-recognin 2, enzymes that are highly expressed in the pancreatic ductal and acinar cells, respectively. Future studies involving large numbers of cases are needed in order to examine the role of H. pylori in autoimmune pancreatitis more fully. Considering the worldwide pancreatic cancer burden, as well as the association between autoimmune pancreatitis and other autoimmune conditions, a complete elucidation of the role played by H. pylori in the genesis of such conditions could have a substantial impact on healthcare.

Relationship between Helicobacter pylori infection and vitiligo: a prospective study

BACKGROUND

Helicobacter pylori is a worldwide bacteria that may affect several extra-gastric systems, including the endocrine, hematologic, vascular, respiratory, immune, and skin. Several skin diseases, including chronic urticaria, alopecia areata, psoriasis, and systemic lupus erythematosis have been found to be associated with H. pylori infection.

AIM

To our knowledge, there are no data showing an association between H. pylori and vitiligo. Therefore, in this study, we wanted to evaluate the relationship between H. pylori and vitiligo.

METHODS

This study is a prospective study carried out in our Gastroenterology and Dermatology and Venereology departments of the Ankara Education and Research Hospital (Ankara, Turkey) between July 2013 and December 2013. Seventy-nine consecutive patients with vitiligo and 72 patients with telogen effluvium (TE) were recruited from the dermatology outpatient clinic. A total of 133 patients with vitiligo (n=68) and TE (n=65) [excluding 18 patients who had suspicious urea breath test (UBT) results] were included in the study. All individuals were tested for H. pylori IgG and CagA. Also, a UBT was performed to detect the presence of H. pylori infection.

RESULTS

There were significantly higher rates of H. pylori positivity, H. pylori CagA, and IgG in serum in the vitiligo group than in the TE group (p<0.05). The number of patients with dyspepsia was significantly higher in the vitiligo group than in the TE group. No statistically significant relationship was seen between H. pylori positivity, CagA, H. pylori IgG, dyspepsia, and the Vitiligo Disease Activity score (p>0.05). Also, when patients with vitiligo were divided into localized and generalized types of vitiligo, there was no association between vitiligo involvement pattern and H. pylori positivity, CagA, H. pylori IgG, and dyspepsia (p>0.05).

CONCLUSION

Additional studies are necessary to evaluate the effect of H. pylori eradication on the clinical course of vitiligo. Further studies are also needed to explain the relationship between H. pylori and the pathogenesis of vitiligo.

Early bacterial infection of the pancreas and course of disease in cerulein-induced acute pancreatitis in rats

BACKGROUND

Bacterial infection of the pancreas aggravates the course of acute pancreatitis. Since bacterial translocation from the gut is likely to be an early event, in an animal model of pancreatitis, we investigated the effect of early bacterial supra-infection of the pancreas on the course of the disease.

METHODS

Six hours after the induction of acute pancreatitis in male Wistar rats (n = 180) by supramaximal stimulation with cerulein (or placebo in a control group), the animals were operated and a suspension of Helicobacter pylori, Escherichia coli or saline were introduced either in the pancreatic duct or interstitium (12 groups of 15 rats each); after 24 h, animals were killed and the following parameters analysed: macroscopic and histologic appearance of the pancreas (score), wet-to-dry weight ratio, pancreas trypsinogen activation peptide level, serum amylase, interleukin-6 and phospholipase A2 activity.

RESULTS

All parameters were increased in rats with cerulein-induced pancreatitis in comparison to placebo. Interstitial and intraductal application of bacteria increased the pancreatic damage. This effect was more evident with the application of E. coli in both cerulein and placebo groups. Application of E. coli but not of H. pylori determined pancreatic activation of trypsinogen, increased mortality and induced the production of interleukin-6.

CONCLUSIONS

Bacterial invasion of the pancreas worsens the histologic and clinical picture of disease and induces a systemic inflammatory response.

Helicobacter species ribosomal DNA in the pancreas, stomach and duodenum of pancreatic cancer patients

AIM: To determine whether gastric and enteric Helicobacter species are associated with pancreatic cancer.

METHODS: Patients with exocrine pancreatic cancer (n = 40), neuroendocrine cancer (n = 14), multiple endocrine neoplasia type 1 (n = 8), and chronic pancreatitis (n = 5) were studied. Other benign pancreatic diseases (n = 10) and specimens of normal pancreas (n = 7) were included as controls. Pancreatic tissue specimens were analyzed by Helicobacter-specific PCR-assay and products were characterized by denaturing gradient electrophoresis and DNA-sequencing. From a subset of the pancreatic cancer patients, gastric and/or duodenal tissue as well as gallbladder and ductus choledochus tissue were analyzed. Gallbladder and choledochus samples were included as controls. Stomach and duodenum samples were investigated to analyze whether a gastric helicobacter might disseminate to the pancreas in pancreatic cancer patients. Pancreatic specimens were analyzed by Bacteroides-specific PCR for detecting the translocation of indigenous gut microbes to the diseased pancreas.

RESULTS: Helicobacter DNA was detected in pancreas (tumor and/or surrounding tissue) of 75% of patients with exocrine cancer, 57% of patients with neuroendocrine cancer, 38% of patients with multiple endocrine neoplasia, and 60% of patients with chronic pancreatitis. All samples from other benign pancreatic diseases and normal pancreas were negative. Thirty-three percent of the patients were helicobacter-positive in gastroduodenal specimens. Surprisingly, H. bilis was identified in 60% of the positive gastroduodenal samples. All gallbladder and ductus choledochus specimens were negative for helicobacter. Bacteroides PCR-assay was negative for all pancreatic samples.

CONCLUSION: Helicobacter DNA commonly detected in pancreatic cancer suggests a possible role of the emerging pathogens in the development of chronic pancreatitis and pancreatic cancer.

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Helicobacter pylori and Malignant Lymphoma in Spain

Helicobacter pylori has been associated with gastric adenocarcinoma and gastric lymphoma. We report on the systematic evaluation of serologic detection of H. pylori in a lymphoma case-control study. Methods: Cases (N = 536) were consecutive patients newly diagnosed with a lymphoid malignancy between 1998 and 2002 in four centers in Spain. Lymphomas were diagnosed and classified using the WHO Classification. Controls (N = 603) were hospitalized patients frequency-matched to the cases by 5-year age group, sex, and study center. Severe immunocompromised patients were excluded as controls. Patients underwent a personal interview and blood sampling. H. pylori infection was evaluated by the presence of IgG antibodies using the Premier enzyme immunoassay kit (Meridian Diagnostics Inc., Cincinnati, OH). Logistic regression analysis was used to estimate the odds ratios and 95% confidence intervals (OR, 95% CI) for lymphoma categories. Results: Anti-H. pylori antibodies were detected in 68.5% of the cases and 71.3% of the controls (P = 0.29) H. pylori was associated with a 3-fold excess risk of splenic marginal B-cell lymphoma (OR = 3.97, 95% CI = 0.92-17.16). H. pylori was not associated with an overall increased risk of extranodal lymphomas (OR = 0.73, 95% CI = 0.44-1.22) but when specific sites were explored, the four mucosa-associated lymphoid tissue and the six diffuse large B-cell lymphomas primary localized in the stomach were all H. pylori seropositive. Conclusion: Persistent infection with H. pylori may be implicated in the development of lymphomas of the gastric mucosa and of the spleen. These results could have clinical implications in the management of splenic marginal zone lymphomas.