Study of Helicobacter pylori genotype status in saliva,dental plaques,stool and gastric biopsy samples

AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens,CONCLUSION:Regard to high similarity in genotype of H.pylori isolates from saliva,stomach and stool,this study support the idea which fecal-oral is the main route of H.pylori transmission and oral cavity may serve as a reservoir for H.pylori,however,remarkable genotype diversity among stomach,saliva and stool samples showed that more than one H.pylori genotype may exist in a same patient.

Role of non-Helicobacter pylori gastric Helicobacters in helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma

Marginal zone lymphomas rank as the third most prevalent form of non-Hodgkin B-cell lymphoma,trailing behind diffuse large B-cell lymphoma and follicular lymphoma.Gastric mucosa-associated lymphoid tissue lymphoma(GML)is a low-grade B-cell neoplasia frequently correlated with Helicobacter pylori(H.pylori)-induced chronic gastritis.On the other hand,a specific subset of individuals diagnosed with GML does not exhibit H.pylori infection.In contrast to its H.pylori-positive counterpart,it was previously believed that H.pylori-negative GML was less likely to respond to antimicrobial therapy.Despite this,surprisingly,increasing evidence supports that a considerable proportion of patients with H.pylori-negative GML show complete histopathological remission after bacterial eradication therapy.Nonetheless,the precise mechanisms underlying this treatment responsiveness are not yet fully comprehended.In recent years,there has been growing interest in investigating the role of non-H.pylori gastric helicobacters(NHPHs)in the pathogenesis of H.pylori-negative GML.However,additional research is required to establish the causal relationship between NHPHs and GML.In this minireview,we examined the current understanding and proposed prospects on the involvement of NHPHs in H.pylori-negative GML,as well as their potential response to bacterial eradication therapy.

Helicobacter pylori and gastric mucosa-associated lymphoid tissue lymphoma:Recent progress in pathogenesis and management

Recent progress in the research regarding the molecular pathogenesis and management of gastric mucosa-associated lymphoid tissue (MALT) lymphoma is reviewed. In approximately 90% of cases, Helicobacter pylori (H. pylori) infection plays the causative role in the pathogenesis, and H. pylori eradication is nowadays the first-line treatment for this disease, which leads to complete disease remission in 50%-90% of cases. In H. pylori-dependent cases, microbe-generated immune responses, including interaction between B and T cells involving CD40 and CD40L co-stimulatory molecules, are considered to induce the development of MALT lymphoma. In H. pylori-independent cases, activation of the nuclear factor-&#x003ba;B pathway by oncogenic products of specific chromosomal translocations such as t(11;18)/API2-MALT1, or inactivation of tumor necrosis factor alpha-induced protein 3 (A20) are considered to contribute to the lymphomagenesis. Recently, a large-scale Japanese multicenter study confirmed that the long-term clinical outcome of gastric MALT lymphoma after H. pylori eradication is excellent. Treatment modalities for patients not responding to H. pylori eradication include a &#x0201c;watch and wait&#x0201d; strategy, radiotherapy, chemotherapy, rituximab immunotherapy, and a combination of these. Because of the indolent behavior of MALT lymphoma, second-line treatment should be tailored in consideration of the clinical stage and extent of the disease in each patient.

Comparative genomic study of gastric epithelial cells co-cultured with Helicobacter pylori

AIM:To identify genes potentially involved in Helicobacter pylori(H.pylori)-induced gastric carcinogenesis.METHODS:GES-1 cells were co-cultured with H.pylori strains isolated from patients with gastric carcinoma(GC,n = 10) or chronic gastritis(CG,n = 10) for in vitro proliferation and apoptosis assays to identify the most and least virulent strains.These two strains were cagA-genotyped and used for further in vivo carcinogenic virulence assays by infecting Mongolian gerbils for 52 wk,respectively;a broth free of H.pylori was lavaged as control.Genomic profiles of GES-1 cells cocultured with the most and least virulent strains were determined by microarray analysis.The most differentially expressed genes were further verified using quantitative real-time polymerase chain reaction in GES-1cells infected with the most and least virulent strains,and by immunohistochemistry in H.pylori positive CG,precancerous diseases,and GC biopsy specimens in an independent experiment.RESULTS:GC-derived H.pylori strains induced a potent proliferative effect in GES-1 cells in co-culture,whereas CG-derived strains did not.The most(from a GC patient) and least(from a CG patient) virulent strains were cagA-positive and negative,respectively.At week 52,CG,atrophy,metaplasia,dysplasia,and GC were observed in 90.0%,80.0%,80.0%,90%,and 60.0%,respectively,of the animals lavaged with the most virulent strain.However,only mild CG was observed in 90% of the animals lavaged with the least virulent strain.On microarray analysis,800 differentially expressed genes(49 up-and 751 down-regulated),involving those associated with cell cycle regulation,cell apoptosis,cytoskeleton,immune response,and substance and energy metabolisms,were identified in cells co-cultured with the most virulent strain as compared with those co-cultured with the least virulent strain.The six most differentially expressed genes(with a betweenness centrality of 0.1-0.2) were identified among the significant differential gene profile network,including JUN,KRAS,BRCA1,SMAD2,TRAF1,and HDAC6.Quantitative real-time polymerase chain reaction analyses verified that HDAC6 and TRFA1 mRNA expressions were significantly more up-regulated in GES-1 cells cocultured with the most virulent strain than in those cocultured with the least virulent strain.Immunohistochemistry of gastric mucosal specimens from H.pyloripositive patients with CG,intestinal metaplasia(IM),dysplasia,and GC showed that moderately positive and strongly positive HDAC6 expression was detected in 21.7% of CG patients,30.0% of IM patients,54.5% of dysplasia patients,and 77.8% of GC patients(P < 0.001).The up-regulation of TRAF1 expressions was detected in 34.8%,53.3%,72.7%,and 88.9% specimens of CG,IM,dysplasia,and GC,respectively(P < 0.001).CONCLUSION:The overexpression of HDAC6 and TRAF1 in GES-1 cells co-cultured with the GC-derived strain and in H.pylori-positive dysplasia and GC suggests that HDAC6 and TRAF1 may be involved in H.pyloriinduced gastric carcinogenesis.

Association of NOD1 and NOD2 genes polymorphisms with Helicobacter pylori related gastric cancer in a Chinese population

AIM:To investigate the association between the tag single nucleotide polymorphisms(TagSNPs) of NOD1 and NOD2 and the risk of developing gastric cancer.METHODS:We conducted a hospital-based case-control study including 296 incident gastric cancer patients and 160 gastritis controls.Eight TagSNPs in the NOD1 and NOD2 genes were selected from the Hapmap database using the haploview software and genotyped by the Sequenom MassArray system.The serum levels of anti-Helicobacter pylori(H.pylori) IgG were measured by enzyme-linked immunosorbent assay to indicate H.pylori infection.The odds ratios(OR) and 95% confidence intervals(CI) were calculated by unconditional logistic regression,including sex and age as confounding factors.RESULTS:The NOD1 rs2907749 GG genotype showed a decreased risk for gastric cancer(OR 0.50,95% CI:0.26-0.95,P = 0.04) while the rs7789045 TT genotype showed an increased risk(OR 2.14,95% CI:1.20-3.82,P = 0.01).An elevated susceptibility to gastric cancer was observed in the subjects with H.pylori infection and the NaOD1 rs7789045 TT genotype(OR 2.05,95% CI:1.07-3.94,P = 0.03) or the NOD2 rs7205423 GC genotype(OR 2.52,95% CI:1.05-6.04,P = 0.04).Haplotype analysis suggested that the distribution of AGT(rs2907749,rs2075820 and rs7789045) in NOD1 between the cases and control groups was significantly different(P corrected:0.04),and the diplotype AGT/AGT was associated with an elevated gastric cancer risk(OR 1.98,95% CI:1.04-3.79,P = 0.04).The association of the NOD1 rs7789045 TT genotype and the diplotype AGT/AGT was significant with H.pylori-related diffuse-type gastric cancer(OR 3.00,95% CI:1.38-6.53,P = 0.01;OR 4.02,95% CI:1.61-10.05,P < 0.01,respectively).CONCLUSION:Genetic polymorphisms in NOD1 and NOD2 may interact with H.pylori infection and may play important roles in promoting the development of gastric cancer in the Chinese population.

Helicobacter heilmannii sensu stricto-related gastric ulcers:A case report

A spiral bacterium (SH9), morphologically different from Helicobacter pylori (H. pylori), was found in a 62-year-old woman&#x02019;s gastric mucosa. Gastroscopic examination revealed multiple gastric ulcers near the pyloric ring; mapping gastric biopsy showed mild mononuclear infiltration with large lymphoid follicles in the antrum, without corpus atrophy. Urea breath test and H. pylori culture were negative, but Giemsa staining of biopsies revealed tightly coiled bacteria that immunostained with anti-H. pylori antibody. Sequencing of SH9 16S rRNA and the partial urease A and B subunit genes showed that the former sequence had highest similarity (99%; 1302/1315 bp) to Helicobacter heilmannii (H. heilmannii) sensu stricto (H. heilmannii s.s.) BC1 obtained from a bobcat, while the latter sequence confirmed highest similarity (98.3%; 1467/1493 bp) to H. heilmannii s.s. HU2 obtained from a human. The patient was diagnosed with multiple gastric ulcers associated with H. heilmannii s.s. infection. After triple therapy (amoxicillin, clarithromycin, and lansoprazole) with regimen for eradicating H. pylori, gastroscopy showed ulcer improvement and no H. heilmannii s.s. upon biopsy.

Serum pepsinogen Ⅱ is a better diagnostic marker in gastric cancer

AIM:To investigate screening makers for gastric cancer,we assessed the association between gastric cancer and serum pepsinogens(PGs).METHODS:The subjects comprised 450 patients with gastric cancer,111 individuals with gastric atrophy,and 961 healthy controls.Serum anti-Helicobacter pylori(H.pylori) immunoglobulin G(IgG),PGⅠand PG Ⅱ were detected by enzyme-linked immunosorbent assay.Gastric atrophy and gastric cancer were diagnosed by endoscopy and histopathological examinations.Odds ratios and 95%CIs were calculated using multivariate logistic regression.RESULTS:Rates of H.pylori infection remained high in Northeastern China.Rates of H.pylori IgG positivity were greater in the gastric cancer and gastric atrophy groups compared to the control group(69.1% and 75.7% vs 49.7%,P < 0.001).Higher levels of PG Ⅱ(15.9 μg/L and 13.9 μg/L vs 11.5 μg/L,P < 0.001) and lower PGⅠ/PG Ⅱ ratio(5.4 and 4.6 vs 8.4,P < 0.001) were found in patients with gastric cancer or gastric atrophy compared to healthy controls,whereas no correlation was found between the plasma PGⅠconcentration and risk of gastric cancer(P = 0.537).In addition,multivariate logistic analysis indicated that H.pylori infection and atrophic gastritis were independent risk factors for gastric cancer.Lower plasma PGⅠ/PG Ⅱ ratio was associated with higher risks of atrophy and gastric cancer.Furthermore,plasma PG Ⅱ?level?significantly?correlated?with?H.pyloriinfected gastric cancer.CONCLUSION:Serum PG Ⅱ concentration and PG Ⅰ/PG Ⅱ ratio are potential biomarkers for H.pyloriinfected gastric disease.PG Ⅱ is independently associated with risk of gastric cancer.

Analysis of ABC (D) stratification for screening patients with gastric cancer

AIM:To evaluate the value of ABC(D) stratification [combination of serum pepsinogen and Helicobacter pylori(H.pylori) antibody]of patients with gastric cancer.METHODS:Ninety-five consecutive patients with gastric cancer were enrolled into the study.The serum pepsinogenⅠ(PGⅠ) /pepsinogenⅡ(PGⅡ) and H.pylori antibody levels were measured.Patients were classified into five groups of ABC(D) stratification according to their serological status.Endoscopic findings of atrophic gastritis and histological differentiation were also analyzed in relation to the ABC(D) stratification.RESULTS:The mean patient age was(67.9±8.9) years.Three patients(3.2%) were classified into group A,7 patients(7.4%) into group A',27 patients(28.4%) into group B,54 patients(56.8%) into group C,and 4patients(4.2%) into group D,respectively.There were only three cases in group A when the patients taking acid proton pump inhibitors and those who had undergone eradication therapy for H.pylori(group A') were excluded.These three cases had mucosal atrophy in the grey zone according to the diagnostic manual of ABC(D) stratification.Histologically,the mean age of the patients with well differentiated adenocarcinoma was significantly higher than that of the patients with poorly differentiated adenocarcinoma(P<0.05) .There were no differences in the pattern of atrophy in the endoscopies between the well differentiated and poorly differentiated groups.CONCLUSION:ABC(D) stratification is a good method for screening patients with gastric cancers.Endoscopy is needed for grey zone cases to check the extent of mucosal atrophy.

Different risk factors influence peptic ulcer disease development in a Brazilian population

AIM: To investigate age, sex, histopathology and Helicobacter pylori (H. pylori) status, as risk factors for gastroduodenal disease outcome in Brazilian dyspeptic patients.tients submitted to upper gastroscopy at Hospital das Clinicas of Marilia, antral biopsy specimens were obtained and subjected to histopathology and H. pylori diagnosis. All patients presenting chronic gastritis (CG) and peptic ulcer (PU) disease localized in the stomach, gastric ulcer (GU) and/or duodenal ulcer (DU) were included in the study. Gastric biopsies (n = 668) positive for H. pylori by rapid urease test were investigated for vacuolating cytotoxin A (vacA ) medium (m) region mosaicism by polymerase chain reaction. Logistic regression analysis was performed to verify the association of age, sex, histopathologic alterations, H. pylori diagnosis and vacA m region mosaicism with the incidence of DU, GU and CG in patients. RESULTS: Of 1466 patients submitted to endoscopy, 1060 (72.3%) presented CG [male/female = 506/554; mean age (year) ± SD = 51.2 ± 17.81], 88 (6.0%) presented DU [male/female = 54/34; mean age (year) ± SD = 51.4 ± 17.14], and 75 (5.1%) presented GU [male/female = 54/21; mean age (year) ± SD = 51.3 ± 17.12] and were included in the comparative analysis. Sex and age showed no detectable effect on CG incidence (overall c 2 = 2.1, P = 0.3423). Sex [Odds ratios (OR) = 1.8631, P = 0.0058] but not age (OR = 0.9929, P = 0.2699) was associated with DU and both parameters had a highly significant effect on GU (overall c 2 = 30.5, P < 0.0001). The histopathological results showed a significant contribution of ageing for both atrophy (OR = 1.0297, P < 0.0001) and intestinal metaplasia (OR = 1.0520, P < 0.0001). Presence of H. pylori was significantly associated with decreasing age (OR = 0.9827, P < 0.0001) and with the incidence of DU (OR = 3.6077, P < 0.0001). The prevalence of m1 in DU was statistically significant (OR = 2.3563, P = 0.0018) but not in CG (OR = 2.678, P = 0.0863) and GU (OR = 1.520, P = 0.2863). CONCLUSION: In our population, male gender was a risk factor for PU; ageing for GU, atrophy and metapla-sia; and H. pylori of vacA m1 genotype for DU.

Lymphomatoidgastropathy mimicking extranodal NK/T cell lymphoma,nasal type:A case report

Extranodal natural killer(NK)/T-cell lymphoma,nasal type,exhibits aggressive tumor behavior and carries a poor prognosis.Recently,lymphomatoid gastropathy with NK/T cell infiltration into gastric mucosa has been recognized as a pseudo-malignant disease which regresses without treatment.Because the conventional immunohistochemical criteria of lymphomatoid gastropathy is similar to that of extranodal NK/T-cell lymphoma nasal type,it is difficult to distinguish between the two conditions by histopathological evaluation only.Here,we report a rare case of lymphomatoid gastropathy in a 57-year-old female.Gastroendoscopy on routine check-up revealed elevated reddish lesions < 1 cm in diameter in the gastric fornix and body.Although repeat endoscopies at 1 and 6 mo later revealed no gastric lesions at any locations without any treatments,at 12 mo later gastric lymphomatoid lesions recurred at gastric fornix and body.Histological examination of endoscopic biopsy specimens at 12 mo showed atypical NK cell infiltration with CD3+,CD4-,CD5-,CD7+,CD8-,CD20-,CD30-,CD56+,CD79a-and T-cell-restricted intracellular antigen-1+ into gastric mucosa.After treatment for Helicobacter pylori(H.pylori) eradication,the lesions disappeared in all locations of the gastric fornix and body over the subsequent 12 mo.Here,we report a case of H.pylori-positive lymphomatoid gastropathy with massive NK-cell proliferation,and also review the literature concerning newly identified lymphomatoid gastropathy based on comparison of extra nodal NK/T-cell lymphoma nasal type.In any case,these lesions are evaluated with biopsy specimens,the possibility of this benign entity should be considered,and excessive treatment should be carefully avoided.Close follow-up for this case of lymphomatoid gastropathy is necessary to exclude any underlying malignancy.