Eradication of gastric cancer is now both possible and practical

In 1994, Helicobacter pylori was declared a human carcinogen. Evidence has now accumulated to show that at least 95% of gastric cancers are etiologically related to H. pylori. An extensive literature regarding atrophic gastritis and its effects on acid secretion, gastric microflora, and its tight association with gastric cancer has been rediscovered, confirmed, and expanded. Methods to stratify cancer risk based on endoscopic and histologic findings or serologic testing of pepsinogen levels and H. pylori testing have been developed producing practical primary and secondary gastric cancer prevention strategies. H. pylori eradication halts progressive mucosal damage. Cure of the infection in those with non-atrophic gastritis will essentially prevent subsequent development of gastric cancer. For all, the age-related progression in cancer risk is halted and likely reduced as eradication reduces or eliminates mucosal inflammation and reverses or reduces H. pylori-associated molecular events such aberrant activation-induced cytidine deaminase expression, double strand DNA breaks, impaired DNA mismatch repair and aberrant DNA methylation. Those who have developed atrophic gastritis/gastric atrophy however retain some residual risk for gastric cancer which is proportional to the extent and severity of atrophic gastritis. Primary and secondary cancer prevention starts with H. pylori eradication and cancer risk stratification to identify those at higher risk who should also be considered for secondary cancer prevention programs. Japan has embarked on population-wide H. pylori eradication coupled with surveillance targeted to those with significant remaining risk. We anticipate that countries with high gastric cancer burdens will follow their lead. We provide specific recommendations on instituting practical primary and secondary gastric cancer prevention programs as well identifying research needed to make elimination of gastric cancer both efficient and cost effective.

Is there any relationship between Le(b) antigen expression and Helicobacter pylori infection?

INTRODUCTION

Helicobacter pylori infection is one of the main causes of peptic ulcer. There are some blood groups acting as receptors for the pathogen. Based on this view and previous attempts, we tried to examine the relationship between Lewis blood group and H. pylori infection.

MATERIALS AND METHOD

Blood and saliva samples were collected from 60 patients with established peptic ulcer induced by H. pylori. Secretory status of each patient was determined by both direct agglutination and saliva tests.

RESULTS

Seventy-two percent of the patients were secretor and expressed Lewis B antigen. This rate in control group was 61%. Statistical analysis showed no significant difference between the two groups.

CONCLUSION

This study did not find any correlation between Le(b) antigen expression and presence of H. pylori-induced peptic ulcer. It is now recommended that other factors like Lewis(x) and sialyl Lewis(x) should be investigated in binding, colonization and virulence of H. pylori infection in the future.

Helicobacter pylori-induced alteration of epithelial cell signaling and polarity: a possible mechanism of gastric carcinoma etiology and disparity

Gastric cancer, a disease of disparity associated with Helicobacter pylori (H. pylori) infection, is the world's second leading cause of cancer deaths. The pathogen H. pylori target the epithelial adhesion receptors, E-cadherin, and β1-integrin, to modulate the host cytoskeleton via disruption of the epithelial cell polarity necessary for maintaining the infection, but how this leads to the development of the carcinoma is widely unclear. While Rho family GTPases' signaling to the cytoskeleton and these receptors is required for initiating and maintaining the infection, the responsible effectors, and how they might influence the etiology of the carcinomas are currently unknown. Here we discuss the potential role of the Cdc42-IQGAP1 axis, a negative regulator of the tumor suppressors E-cadherin and β1-integrin, as a potential driver of H. pylori-induced gastric carcinoma and propose avenues for addressing its disparity. Chronic dysfunction of the IQGAP1-signaling pathway, resulting from H. pylori-induced disruption of cell polarity, can explain the pathogenesis of the carcinoma, at least, in subsets of infected population, and thus could provide a potential means for personalized medicine.

Diagnosis of the infection by the Helicobacter pylori through stool examination: method standardization in adults

OBJECTIVES

Infection caused by Helicobacter pylori (H. pylori) is one of the most common causes of chronic infection in the world. The presence of the infection is strongly associated with the neoplasia of the gastrointestinal tract, and its diagnosis is easily made by means of invasive or non-invasive methods. Among such methods, the H. pylori antigen detection in stool through ELISA technique is easily performed and it is an alternative to endoscopy in children, since this exam is not usually indicated in this age group. The aim of the current study is to establish the standardization of the ELISA method for the detection of H. pylori in stool specimens in Brazil.

DESIGN AND METHODS

Patients between 18 and 70 years of age were randomly selected in the gastroenterology ambulatory center at Faculdade de Medicina do ABC between 2007 and 2009. They all answered a questionnaire to investigate possible dyspeptic symptoms and then underwent endoscopy and detection of H. pylori through no more than 4 methods. Besides the gastric biopsy, established as the gold standard test, the urease test, the stool ELISA test and serology were also methods applied.

RESULTS

The sensitivity and specificity of the exams in this sample were respectively 87.2% and 44% for the stool ELISA test, 41.9% and 64% for serology, 65.6% and 58.8% for the urease test and 100% and 80.8% for the clinical analysis.

CONCLUSIONS

The ROC curve showed a good correlation between the compared methods. In Brazil the standardization of the ELISA test for the detection of H. pylori in stool specimens constitutes a non-invasive diagnostic alternative.

Association between vitamin B12 level and anti-parietal cells and anti-intrinsic factor antibodies among adult Jordanian patients with Helicobacter pylori infection

OBJECTIVE

Evaluate the association of Helicobacter pylori infection with anti-parietal cell antibodies (APCA) and anti-intrinsic factor antibodies (AIFA) and their impact on vitamin B12 serum level.

PATIENTS AND METHODS

One hundred patients (M/F: 43/57; age 46.5±17.5 years) who underwent upper gastrointestinal endoscopy at King Abdullah University Hospital, Irbid, Jordan were enrolled in the study. The patients were grouped as H. pylori-infected (n=81) or H. pylori negative (n=19) by histopathological examination. Fasting serum vitamin B12 levels, anti-parietal cell antibodies and anti-intrinsic factor antibodies for patients and controls were determined.

RESULTS

Anti-parietal cell antibodies and anti-intrinsic factor antibodies were positive in 9.9% and 18.5% of H. pylori-positive patients respectively. None of the H. pylori negative subjects had anti-parietal cell antibodies or anti-intrinsic factor antibodies. Serum vitamin B12 level was lower in the H. pylori-infected patients (275±70.4pg/mL) than in controls (322.9±60.7pg/mL; p<0.05). H. pylori was positive in 94% of the low-vitamin B12 group compared with 64.6% of the normal-vitamin B12 group (p<0.5).

CONCLUSION

Patients with H. pylori infection are more likely to have anti-parietal cell antibodies and anti-intrinsic factor antibodies. There was an association between H. pylori infection and lower vitamin B12 levels. H. pylori infection might be a significant factor in the pathogenesis of autoimmune gastritis.

Bioactivity and immunological evaluation of LPS from different serotypes of Helicobacter pylori

BACKGROUND AND OBJECTIVES

Helicobacter pylori is the causative agent of peptic ulcer disease and a co-factor in development of gastric malignancies. LPS are among toxic substances produced by H. pylori exhibiting low endotoxic activity compared to typical bacterial LPS. The aim of this study was to investigate bioactivity of LPS produced by different serotypes of Helicobacter pylori compared to Escherichia coli and Brucella abortus LPS.

MATERIALS AND METHODS

Bacterial LPS was extracted by the hot phenol-water method. Biological activities of LPS were determined via the limulus lysate assay, pyrogenic assay, and blood pressure and PBMC induction test in rabbits.

RESULTS

Biological activity of O2 serotype LPS of H. pylori was less than the biological activity of other H. pylori serotypes.

CONCLUSION

Our data supported the hypothesis that the unique bacterial LPS of the O2 serotype must be included in the formulation of a multivalent H. pylori vaccine.

Gene methylation in gastric cancer

Gastric cancer is one of the most common malignancies and remains the second leading cause of cancer-related death worldwide. Over 70% of new cases and deaths occur in developing countries. In the early years of the molecular biology revolution, cancer research mainly focuses on genetic alterations, including gastric cancer. Epigenetic mechanisms are essential for normal development and maintenance of tissue-specific gene expression patterns in mammals. Disruption of epigenetic processes can lead to altered gene function and malignant cellular transformation. Recent advancements in the rapidly evolving field of cancer epigenetics have shown extensive reprogramming of every component of the epigenetic machinery in cancer, including DNA methylation, histone modifications, nucleosome positioning, noncoding RNAs, and microRNAs. Aberrant DNA methylation in the promoter regions of gene, which leads to inactivation of tumor suppressor and other cancer-related genes in cancer cells, is the most well-defined epigenetic hallmark in gastric cancer. The advantages of gene methylation as a target for detection and diagnosis of cancer in biopsy specimens and non-invasive body fluids such as serum and gastric washes have led to many studies of application in gastric cancer. This review focuses on the most common and important phenomenon of epigenetics, DNA methylation, in gastric cancer and illustrates the impact epigenetics has had on this field.

Searching the H. pylori; serology & PCR in children with adenoid hypertrophy and rhino sinusitis: a cross sectional study, Tehran, Iran

OBJECTIVE

Searching the H. pylori -DNAs in adenoid and IgA, IgG antibodies in serum of children.

METHODS

A cross- sectional study had done upon 53 children (Mean age 8 ±1.9 years) with adenoid surgery in ENT and Pediatric Department of Rasul Akram Hospital (2008-2010). Of 53 cases with adenoid surgery, 40 cases had rhino sinusitis (in sinus CT scan). The resected adenoid tissues (n=40) centrifuged and homogenized and its DNAs extracted and searched for H. pylori- DNAs by qualitative PCR. Serum H. pylori antibodies (IgG &IgA ELISA) calculated quantitatively. Chi square values (p < 0.05) calculated for all categorical variables. The agreement between serologic test and PCR was assessed by the calculation of kappa statistic.

RESULTS

Positive PCR for H. pylori detected in 15%of cases; regardless of sex and age of cases. Positive IgA: 17.5% (7/40) and IgG: 20% (8/40) respectively. All cases with positive H. pylori- IgG were female; p=0.003 and meaningful differences in mean age of cases observed for positive IgA (p=0.001) and IgG (p=0.01). Poor agreement observed between positive PCR and serum IgG&IgA (Fisher's Exact test=0.3; 0.5).

CONCLUSION

Positive PCR in adenoid tissue (15%) was very close to positive serum IgA (15%) but without any agreement for each case. The H. pylori infection may have a relative role at least in 15% of children with adenoid surgery. Chronic sinusitis and ear infection might be added to infected adenoid tissue as a reservoir for bacteria. The search by specific culture may elucidate better the role of H. pylori infections in both gastric and adenoid tissues. The decision for use of antibiotics to eradicate the H. pylori infection in recurrent or chronic adenotonsillar infections (with rhinosinusitis) before adenoid surgery needs Randomized Control Trial (RCT) studies. Drug of choice for eradication of H. pylori dependent to antibiotic sensitivity test in each country.

Helicobacter, Inflammation, and Gastric Cancer

Helicobacter pylori infection leads to long-lasting chronic inflammation and represents the most common risk factor underlying gastric cancer. Recently, new insights into the mechanisms through which H. pylori and mucosal inflammation lead to cancer development have emerged. H. pylori virulence factors, in particular specific CagA genotypes, represent main factors in gastric cancer, inducing altered intracellular signaling in epithelial cells. The chronic nature of H. pylori infection appears to relate to the VacA virulence factor and Th17/Treg mechanisms. A role of H. pylori infection in epigenetic and microRNA deregulation has been shown. Mutation of the epithelial cell genome, a hallmark of cancer, was demonstrated to accumulate in H. pylori infected stomach partly due to inadequate DNA repair. Gastric stem cells were shown to be targets of oxidative injury in the Helicobacter-inflammatory milieu. Recent advances emphasizing the contribution of bacterial factors, inflammatory mediators, and the host epithelial response in gastric carcinogenesis are reviewed.

Diversity of Helicobacter Pylori cagA and vacA Genes and Its Relationship with Clinical Outcomes in Azerbaijan, Iran

PURPOSE

The purpose of this research was to analyze cagA and vacA genotypes status in H. pylori isolates and relationship with clinical outcomes.

METHODS

Gastric biopsy specimens were cultured for H. pylori isolation and cagA and vacA genes were detected in these isolates. Data were collected and the results were analyzed using χ2 and Fishers exact tests by SPSS software version. 16.

RESULTS

Of the total 115 H. pylori isolates, 79 (68.7 %) were cagA positive and 82 (71.3%) of isolates contained the s1 allele which 33 (28.7%) were subtype s2. s1m2 was the most frequent vacA allelic combination in the H. pylori isolates examined (63 cases), followed by s2m2 (31 cases), s1m1 (19 cases) and s2m1 (2 case). Strains cagA positive were more frequent in peptic ulcer diseases patients than non ulcer diseases patients, as 47 (59.5%) and 32 (40.5%), while cagA negative were low, as 15 (41.7%) and 21 (58.3%), respectively.

CONCLUSION

We found that the cagA and vacA status were not related to clinical outcomes in this area. Overall, in the present study, vacA s1/m2, cagA-positive strains were predominant irrespective of clinical outcome, but s2/m1 was rare.

Association of the virulence factors of Helicobacter pylori and gastric mucosal interleukin-17/23 mRNA expression in dyspeptic patients

The molecular pathways that control Helicobacter pylori (Hp)-associated inflammatory reaction are complex, but locally induced cytokines and virulence factors seem to have a major role in maintaining the ongoing inflammation. Therefore this study was aimed to evaluate the association of the virulence factors of Hp and gastric mucosal interleukin-17/23 mRNA expression in dyspeptic patients. Mucosal IL-17 and IL-23 mRNA expression in H. pylori infected and non-infected gastric biopsies were determined by real-time RT-PCR. Virulence factors, vac-A and cag-A were evaluated using PCR. There was no significant difference in mucosal IL-17 and IL-23 mRNA expression between H. pylori infected and non-infected patients. Their expression in mucosa did not correlate with chronic gastritis and chronic active gastritis. IL-17 and IL-23 mRNA expression in mucosa of patients with vacA m1 were significantly higher than those observed in patients with vacA m2. The severity of polymorphonuclear infiltration and chronic active gastritis was higher in cag-A positive than cag-A negative patients. H. pylori infections carrying the vacA m1 allele have higher IL-17 and IL-23 mRNA and the current study suggests that the virulence factor vacA allele's m1 are important for the severe gastric inflammation.

Symptom-histopathology relation in upper GI endoscopy

OBJECTIVE

The purpose of this article is to examine the correlation between information obtained from patients before endoscopy and histopathological findings.

MATERIAL AND METHODS

One thousand, five hundred and thirty-six patients underwent upper GI endoscopy between January 2011-September 2012, without distinction of age and sex were included in the study. Patients with alarm symptoms, dyspepsia, epigastric pain, gastroesophageal reflux were recorded. Tissue samples taken for histopathological examination and H. pylori screening were evaluated by Giemsa stain. The information given by the patients and histopathological findings were comparatively evaluated.

RESULTS

Six hundred and twenty-four patients (40.6%) were male and 912 (59.4%) were female. Mean age was 45 years (18-90). H. pylori was positive in 416 patients with dyspepsia (58.8%), 172 patients with epigastric pain (54.4%), 52 patients with GER symptoms (28.3%) and 128 patients with alarm symptoms (50.8%). Four patients with dyspepsia (0.6%) and 20 patients with alarm symptoms (7.9%) were diagnosed with stomach cancer.

CONCLUSION

The main factor should be considered as the presence of at least one of the alarm symptoms when planning an upper GI endoscopy in a patient. In the presence of at least one of the alarm symptoms, an upper GI endoscopy should be performed regardless of age. Under the age of 50 and for patients without alarm symptoms, medical treatment can be tried before performing upper GI endoscopy. Patients with GER symptoms but not diagnosed as reflux esophagitis, should be treated long-term even when symptoms decline with initial treatment.

Agreement rate of rapid urease test, conventional PCR, and scorpion real-time PCR in detecting helicobacter pylori from tonsillar samples of patients with chronic tonsillitis

Background:

Helicobacter pylori is capable of inducing systemic inflammatory reactions through immunological processes. There are several methods to identify the presence of H. pylori in clinical samples including rapid urease test (RUT), conventional polymerase chain reaction (PCR), and the Scorpion real-time PCR.

Aim:

The aim of the present study is to compare the agreement rate of these tests in identifying H. pylori in tonsillar biopsy specimens collected from patients with chronic tonsillitis.

Materials and Methods:

A total of 103 tonsil biopsy samples from patients with clinical signs of chronic tonsillitis were examined with RUT, PCR, and Scorpion real-time PCR. The degree of agreement between the three tests was later calculated.

Results:

There was a poor degree of agreement between RUT and PCR and also RUT and Scorpion real-time PCR (Kappa=0.269 and 0.249, respectively). In contrast with RUT, there was a strong degree of agreement between PCR and Scorpion real-time PCR (Kappa=0.970).

Conclusion:

The presence of a strong agreement between the Scorpion real-time PCR and PCR as well as its technical advantage over the conventional PCR assay, made the Scorpion real-time PCR an appropriate laboratory test to investigate the presence of H. pylori in tonsillar biopsy specimens in patients suffering from chronic tonsillitis.

Mucosal IgA & IL-1β in Helicobacter pylori Infection

Helicobacter pylori infection stimulates strong local inflammatory and specific IgA antibody production. The influence of antibodies on the bacterial colonization is not clear. Here, we have analysed the association between the mucosal IgA level and IL-1β in various manifestations of the infection seen endoscopically. Antral biopsies of 57 dyspeptic patients were taken for culture, histology and estimation of mucosal levels of anti-H. pylori IgA and IL-1β. Mean mucosal IgA level was higher in patients with normal mucosa compared to all other groups and lower IgA level was associated with higher bacterial density. IL-1β was higher in ulcer patients and suspicious malignancy group as compared to normal group and higher level of IL-1β was associated with higher grades of metaplasia. Present study indicates that local immunity seems to have a protective role against H. pylori infection and higher level of IL-1β induced by the pathogen may be associated with metaplasia and carcinogenesis.

MALT Lymphoma of Caecum Presenting as Acute Intestinal Obstruction: A Case Report

Mucosa-associated lymphoid tissue lymphomas (MALT lymphoma) are well known, but colonic MALT lymphomas are extremely rare. We report the first case of mucosa-associated lymphoid tissue (MALT) lymphoma in the cecum from India presenting as acute intestinal obstruction with mass in right iliac fossa showing diffuse thickening of ascending colon and caecum with obliterated lumen along with nodular mass on CECT scan of abdomen. On video colonoscopy, circumferential ulcerated growth was seen at cecum, and the rest of the colon was normal. Multiple biopsies from growth suggested malignancy. Right hemicolectomy was performed. The histopathology of resected specimen demonstrated low-grade B-cell MALT lymphoma of the cecum, and the depth of invasion was up to the muscular layer. This was confirmed by immunohistochemistry.

Case-control study of dietary pattern and other risk factors for gastric cancer

BACKGROUND

The rates of gastric cancer reported from Ardabil Province of Iran, are among the highest in the world. The aim of this study was to investigate the risk factors for gastric cancer in Ardabil Province.

METHODS

This case-control study was conducted on 128 adults with mean age of 56.5 ± 12.8 yr old in Ardebil City, Iran in 2010 - 2011. Forty-two people with gastric cancer and 86 healthy people were recruited. Participants were interviewed using a structured questionnaire. Fasting blood samples were taken for measurement of IgG and IgA indices against Helicobacter pylori infection. Data were analyzed using the Chi-square and Independent sample t-test. 

RESULTS

Diet and H. pylori infection indices had the significant relationship with gastric cancer (P<0.05). Among dietary patterns, drinking hot tea, low intake of fresh vegetables and fruits, and unsaturated fat were the most significant risk factors (P<0.05). In gastric cancer patients, the levels of serum IgG and IgA as indicator of H. pylori infection were significantly (P<0.05) higher than the healthy subjects (IgG 37.7 ± 29.3 vs. 16.9 ± 11.1 U/ml and IgA 50.5 ± 44.7 vs. 22.9 ± 15.8 U/ml). No significant relationship was observed between tobacco smoking and alcohol consumption with gastric cancer.

CONCLUSION

Dietary pattern especially drinking hot tea and low consumption of unsaturated fat, fresh vegetables, and fruits, as well as H. pylori infection were the most important risk factors in gastric cancer patients.

Efficacy of esomeprazole in treating acid-related diseases in Japanese populations

Esomeprazole (Nexium^®; AstraZeneca), the S-isomer of omeprazole, is the first proton pump inhibitor (PPI) to be developed as an optical isomer. Compared with omeprazole, esomeprazole has an improved pharmacokinetic profile with regards to CYP2C19 (S-mephenytoin 4′-hydroxylase) genotype, showing increased systemic exposure and less interindividual variability. Further, esomeprazole is a more potent acid inhibitor than other currently available PPIs and is therefore used as a first-line drug for acid-related diseases. While esomeprazole has been available in a number of countries worldwide, the compound only received authorized permission to be marketed in Japan in September 2011. The standard esomeprazole dose in Japan for the treatment of peptic ulcers and gastroesophageal reflux disease (GERD) is 20 mg. Other advised dosages are 10 mg for nonerosive reflux disease and 20 mg twice-daily dosing for eradication of Helicobacter pylori. In Japanese, the effective rate of esomeprazole 20 mg during 24 weeks for GERD patients is 92.0% (88.0%–96.0%), while the prevention of peptic ulcer development using 20 mg for 24 weeks in patients treated with nonsteroidal anti-inflammatory drugs is 96.0% (92.8%–99.1%). Although clinical data are limited, the usefulness of esomeprazole is expected in Japanese subjects given the reduced prevalence of CYP2C19 rapid metabolizers in Japan compared with Western countries.

Outer membrane biogenesis in Escherichia coli, Neisseria meningitidis, and Helicobacter pylori: paradigm deviations in H. pylori

The bacterial pathogen Helicobacter pylori is capable of colonizing the gastric mucosa of the human stomach using a variety of factors associated with or secreted from its outer membrane (OM). Lipopolysaccharide (LPS) and numerous OM proteins have been shown to be involved in adhesion and immune stimulation/evasion. Many of these factors are essential for colonization and/or pathogenesis in a variety of animal models. Despite this wide array of potential targets present on the bacterial surface, the ability of H. pylori to vary its OM profile limits the effectiveness of vaccines or therapeutics that target any single one of these components. However, it has become evident that the proteins comprising the complexes that transport the majority of these molecules to the OM are highly conserved and often essential. The field of membrane biogenesis has progressed remarkably in the last few years, and the possibility now exists for targeting the mechanisms by which β-barrel proteins, lipoproteins, and LPS are transported to the OM, resulting in loss of bacterial fitness and significant altering of membrane permeability. In this review, the OM transport machinery for LPS, lipoproteins, and outer membrane proteins (OMPs) are discussed. While the principal investigations of these transport mechanisms have been conducted in Escherichia coli and Neisseria meningitidis, here these systems will be presented in the genetic context of ε proteobacteria. Bioinformatic analysis reveals that minimalist genomes, such as that of Helicobacter pylori, offer insight into the smallest number of components required for these essential pathways to function. Interestingly, in the majority of ε proteobacteria, while the inner and OM associated apparatus of LPS, lipoprotein, and OMP transport pathways appear to all be intact, most of the components associated with the periplasmic compartment are either missing or are almost unrecognizable when compared to their E. coli counterparts. Eventual targeting of these pathways would have the net effect of severely limiting the delivery/transport of components to the OM and preventing the bacterium's ability to infect its human host.

Mechanism of H. pylori intracellular entry: an in vitro study

The majority of Helicobacter pylori reside on gastric epithelial cell surfaces and in the overlying mucus, but a small fraction of H. pylori enter host epithelial and immune cells. To explore the role of the nudA invasin in host cell entry, a ΔnudA deletion derivative of strain J99 was constructed and transformants were verified by PCR and by fluorescence in situ hybridization. AGS cells were inoculated with either wild type (WT) strain J99 or its ΔnudA mutant to determine the fraction of bacteria that were bound to the cells and were present inside these cells using the gentamicin protection assay. We observed no significant difference between either the density of H. pylori bound to AGS cell membranes or the density of intracellular H. pylori. To further explore this finding, separate chambers of each culture were fixed in glutaraldehyde for transmission electron microscopy (TEM) and immunogold TEM. This addition to the “classical” gentamicin assay demonstrated that there were significantly more intracellular, and fewer membrane-bound, H. pylori in WT-infected AGS cells than in ΔnudA allele infected cells. Thus, the sum of intracellular and membrane-bound H. pylori was similar in the two groups. Since no other similar TEM study has been performed, it is at present unknown whether our observations can be reproduced by others Taken together however, our observations suggest that the “classical” gentamicin protection assay is not sufficiently sensitive to analyze H. pylori cell entry and that the addition of TEM to the test demonstrates that nudA plays a role in H. pylori entry into AGS cells in vitro. In addition, deletion of the invasin gene appears to limit H. pylori to the AGS cell surface, where it may be partly protected against gentamicin. In contrast, this specific environment may render H. pylori more vulnerable to host defense and therapeutic intervention, and less prone to trigger normal immune, carcinogenic, and other developmental response pathways.

Helicobacter pylori in Iran: A systematic review on the association of genotypes and gastroduodenal diseases

BACKGROUND

Helicobacter pylori (H. pylori) infection is known as a major etiologic factor for a variety of gastroduodenal diseases. In Iran, with a high rate of H. pylori infection close to 90%, numerous studies have revealed many aspects of interaction between the bacterium, mucosal surface and induction of disease outcome. The organism is genetically diverse and several virulence factors are attributed to the more virulent strains. The well-characterized virulence factors of H. pylori are cytotoxin associated gene A and vacuolating cytotoxin gene A. The distribution pattern of H. pylori genotypes and its association with disease status varies geographically. The present review focused on the virulence factors and genotyping of H. pylori in relation to gastroduodenal disorders in different regions of Iran.

METHODS

In total, 398 studies were reported on different aspects related to H. pylori in our electronic search from 1995-2011. H. pylori infection and its virulence factors in association with disease status were investigated in 159 reports. Looking specifically at the gastrointestinal tract disorders, the most relevant reports including 37 papers were selected.

RESULTS

We found no correlation of cagA genotype and disease status in the majority of studies, whereas vacA was demonstrated as a useful marker in predicting the disease outcome. The results of reports on other virulence factors of H. pylori such as blood group antigen-binding adhesion gene A, the induced by contact with epithelium gene A, the outer inflammatory protein A, the duodenal ulcer promoting gene A, and Helicobacter outer membrane gene and their relation with disease status were contradictory.

CONCLUSIONS

Although different markers of H. pylori were emphasized as useful when predicting disease outcomes in some studies, the inconsistent researches and the scarcity of data made any conclusion or even comparison impossible. Considering the gap of information observed during our search relating to genotyping and other aspects of H. pylori infection, further investigations are suggested.

Imprint cytology: a simple, cost effectiveness analysis for diagnosing Helicobacter pylori, in west of Iran

BACKGROUND

This study was to determine the sensitivity, specificity, positive predictive value (PPV), negative predictive values (NPV) and agreement between two methods of the stained gastric imprint cytology smears and stained gastric specimen biopsy mucosal methods for detection of H. pylori.

METHODS

Air-dried imprint smears of gastric biopsies from 330 patients were stained by the Grunwald-Giemsa method in the endoscopy suite and examined for H. pylori, providing results within minutes. The grade of H pylori infection was documented. The same biopsy was processed and stained with H&E and Grunwald-Giemsa stains, and reviewed by two different pathologists blind to the imprint cytology results.

RESULTS

Ninety-four of the 238 patients were male with a mean age of 46 (±16.4) years. Based on histology, the H. pylori prevalence was very high at 77.87% and according to cytology H.Pylori prevalence was high at 75.45% in this region our country. The sensitivity and specificity of imprint cytology in the detection of H. pylori were 96.88% and 90.12%, respectively. The PPV and NPV were 96.88% and 90.12%, respectively. The agreement between two diagnostic methods was 95.26% which confirms reliability of imprint cytology method for ion of H.pylori detection.

CONCLUSION

Gastric imprint smears stained with Grunwald-Giemsa method is a rapid and cost effective method in addition to histology for detecting H. pylori in patients undergoing upper gastrointestinal endoscopy and biopsy. It does not require any additional biopsy.

Helicobacter Pylori DNA in Liver Tissues From Chronic Hepatitis C Egyptian Patients

Background

Hepatitis C virus (HCV) is considered the most common etiology of chronic liver disease in Egypt, which may progress to cirrhosis and hepatocellular carcinoma (HCC). Previous studies have documented an association between Helicobacter pylori (H. pylori) infection and liver cirrhosis with or without HCC. This study aimed to investigate the presence of H. pylori DNA in the liver tissue of Egyptian patients with chronic hepatitis C (CHC).

Methods

Fifty-two CHC Egyptian patients were enrolled in this study. Plasma anti-H. pylori IgG was assessed with ELISA. Liver biopsies were tested for presence of Helicobacter DNA using genus specific nested polymerase chain reaction (PCR) and species was identified by sequencing.

Results

Anti-H. pylori IgG was detected in 31/52 (59.6%) CHC patients while Helicobacter DNA was detected in 6 (11.5%) patients, all were H. Pylori by sequencing. Helicobacter DNA was more frequent in patients with high stage liver fibrosis (33.3%) than in those with low stage fibrosis (2.7%) (P = 0.006). There was no association between the presence of H. pylori DNA in the liver and age, gender of patients, liver function tests, AFP levels or viral load.

Conclusions

These data confirm the presence of H. pylori DNA in liver of some CHC Egyptian patients and suggest an association of this bacterium with progression of liver fibrosis.

Relation between ABO blood groups and Helicobacter pylori infection in symptomatic patients

Epidemiological studies have demonstrated higher frequencies of the O blood group and the nonsecretor phenotype of ABH antigens among patients suffering from peptic ulcers. Since Helicobacter pylori has been established as the main etiological factor in this disease, controversies about the associations of the ABO and Lewis blood group phenotypes and secretor and nonsecretor phenotypes in relation to susceptibility towards infection by this bacillus have been presented. The aim of this study was to verify the frequencies of ABO and Rhesus (Rh) blood groups in H. pylori seropositive symptomatic patients. The study included (n = 1108) patients with dyspepsia symptoms referred from an outpatient clinic in Erbil city for investigation. Age, sex, and residency were recorded as a routine laboratory framework. Patients underwent SD Bioline (Standard Diagnostics Inc, Kyonggi-do, South Korea) and enzyme-linked immunosorbent assay serologic tests for H. pylori. ABO blood group phenotypes were determined by a standard hemagglutination test. Results showed that 64.8% of patients (n = 718/1108) were seropositive for H. pylori infection, and (35.2%) (n = 390/1108) were seronegative. Of the seropositive patients, 40.8% (n = 293/718) were male and 59.2% (n = 425/718) were female; while of the seronegative patients, 46.7% (n = 182/390) were male and 53.3% (n = 208/390) were female. The mean age for seropositives and seronegatives was (38.0 ± 14.6) years and (37.6 ± 15.7) years respectively. The frequency of the ABO and Rh-positive (Rh+) blood groups among seropositive patients was (A = 32.0%, B = 19.5%, AB = 6.7%, O = 41.8%, and Rh+ = 92.5%) and was (A = 32.3%, B = 28.2%, AB = 8.0%, O = 31.5%, and Rh+ = 92.5%) in seronegatives. The results of this study suggest that ABO blood groups, age, and gender influence seropositivity for H. pylori infection.

Helicobacter pylori bab genes during chronic colonization

Helicobacter pylori BabA adhesin metastability could yield variants with potential for periodic activation and deactivation of their mediated adherence. babA/B or babB/A chimeras could play an important role in translational regulation. We investigated the frequency of different bab gene profiles in paired isolates from antrum and corpus recovered from patients with chronic gastritis. Isolates from 174 biopsies from 34 patients were included, and bab genes at the three common chromosomal loci were investigated. Inter-micro-niche variation was found in 1/4 patients, counting duplicate copies of babA or babB, babB/A or babA/B chimeras, opposite location of babA and babB or babC and babB, and absence of babB ATG translational codon. Truncated BabA was identified in 2/34 patients without inter-micro-niche variation. Isolates from 12/34 patients harbored babA/B or babB/A chimeras -either in one, several or all micro-niches indicating that chimera formation is a common mechanism to control BabA expression. To note, babA gene was absent in 11/34 patients, and in this population, babA/B chimeras which lack expression predominated over babB/A, able to exhibit Le(b) binding phenotype.