NUD Patients Research Articles

Clinical profile and spectrum of Duodenal biopsy and other investigational abnormalities in NUD patients

Clinical profile and spectrum of Duodenal biopsy and other investigational abnormalities in NUD patients

Multiplex serology of Helicobacter pylori antigens in detection of current infection and atrophic gastritis - A simple and cost-efficient method

IntroductionHelicobacter pylori express a large array of antigens, each of which is duly responsible for successful colonization and pathogenesis. Here, we have studied host serum antibody responses to four of its immunodominant antigens in association with the infection status and the resulting clinical outcomes. MethodsFor this purpose, four individual H. pylori proteins (UreB, CagA, Tip-α and HP0175) were produced in recombinant forms. Serum antibody responses of 246 (75 GC and 171 NUD) patients, against the above antigens, were evaluated by multiplex immunoblotting. The associations between the resulting data and the infection status, as well as clinical outcomes were evaluated using logistic regression models. ResultsSerum antibodies to all four recombinant antigens increased the chances of detecting screening ELISA-positive subjects, in an escalating dose-dependent manner, ranging from 2.6 (1.5–4.7) for HP0175 to 14.3 for UreB (4.3–50.7), exhibiting the lowest and highest odds ratios, respectively (PAdj ≤ 0.001), such that 98.2% of the subjects with antibodies to all four antigens, were also positive by the screening ELISA (P < 0.0001). Among the screening ELISA-positive subjects, the three antigens of CagA, Tip-α, and HP0175 were able to segregate current from past H. pylori infection (P < 0.05). Accordingly, subjects with antibodies to one or more antigen(s) were at 5.4 (95% CI: 1.8–16.4) folds increased chances of having current infection, as compared to triple negatives (PAdj = 0.003). In reference to the clinical outcomes, those with serum antibodies to CagA were more prevalent among gastric cancer, as compared to NUD patients (ORAdj: 5.4, 95% CI: 2.4–12.2, PAdj < 0.0001). When NUD patients were categorized according to their histopathologic status, multiple antigen analysis revealed that subjects with serum antibodies to one or more of the 3 current infection-positive antigens (CagA, Tip-α, and HP0175) were at 9.7 (95% CI: 2.1–44.9, P = 0.004) folds increased risk of atrophic gastritis, in reference to triple negatives. ConclusionThe non-invasive multiplex serology assay, presented here, was able to not only detect subjects with current H. pylori infection, it could also screen dyspeptic patients for the presence of gastric atrophy. This simple and cost-efficient method can supplement routine screening ELISAs, to increase the chances of detecting current infections as well as atrophic gastritis.

Cigarette smoking status and Helicobacter pylori infection in non-ulcer dyspepsia patients

Background and objectiveThere is strong, if not conclusive, evidence that Helicobacter pylori plays a role in duodenal ulcer disease, gastric ulcer disease, and gastric adenocarcinoma. The potential association with nonulcer dyspepsia, however, still remains unclear despite the large number of studies that have attempted to elucidate it, smoking has been found to be related to a higher incidence of H. pylori in non-ulcer dyspepsia patients. Therefore we aimed to find out the incidence of H. pylori infection in our group of non-ulcer dyspepsia patients and to study the relationship between smoking status of the patients and H. pylori positivity in them. Patient and methodsAll patients presenting with dyspepsia in whom upper gastro-intestinal endoscopy had ruled out acute or chronic peptic ulceration, esophagitis, gastric cancer, and other structural and metabolic causes were taken as patients of non-ulcer dyspepsia. Urea breath test was used for all patients. The history was reviewed; especially their smoking statuses were recorded. ConclusionIn our study we found that the prevalence of H. pylori positivity was 43% and there was no statistically significant difference between smokers, non-smokers and ex smokers in the positivity rate of H. pylori in NUD patients.

Molecular detection of host cytokine expression in Helicobacter pylori infected patients via semi-quantitative RT-PCR

Background:Helicobacter pylori (Hp) is a bacterium recognised as a main causative agent for the development of chronic active gastritis, peptic ulcer disease, gastric adenocarcinoma and primary gastric lymphoma. Objective: Determination of the levels of IFN-γ (pro-inflammatory) and IL-4 (anti inflammatory) cytokine expression as indicators of Th1 and Th2 immune responses in gastric cancer (GC) and non gastric cancer (Non GC) dyspeptic patients by gene specific RT-PCR. Materials and Methods: Biopsy specimens were collected from three groups of gastric cancer (GC =18), non ulcer dyspepsia (NUD = 38) and peptic ulcer patients (PUD =20). Total RNA was extracted and complementary DNA was synthesised. PCR amplification was performed for HPRT, IFN-γ and IL-4 cytokines and the intensity of each band was measured by densitometry and normalized against HPRT expression as a house keeping gene. Results: Comparison of the results from different groups of patients indicated that IFN-γ gene expression was similar in nonGC dyspeptic patients (NUD and PUD groups; 3.38 ± 0.57,3.43 ± 0.41, respectively) whereas, in GC patients, it was significantly higher than others (5.52 ± 0.59; P < 0.0001). On the other hand, IL-4 gene expression showed no significant difference between NUD and GC patients (2.81 ± 0.43,2.3 ± 0.12 respectively), whereas the expression rate of this cytokine was significantly higher in PUD patients (3.7 ± 0.1; P 0.05). Our data indicate an association between Th1 and Th2 immune responses and the development of gastric cancer and peptic ulcer disease respectively.

Investigation of cagI and cagII in H. pylori Isolated from Dyspepsia Patients in Iran

Background: The major virulence factor of H. pylori is the cag pathogenicity island divided into two parts: the upstream cagII region and the downstream cagI region. The downstream region includes cagA, cagE, and themost important gene introduced in cagII is cagT. The aim of this study was to investigate the important markers of cagI and cagII regions in Helicobacter pylori isolated from Iranian peptic ulcer and non ulcer disease patients. Methods and materials: 80 clinical isolates of H. pyloriwere collected from 120 patients with gastric disorders. The genomic DNA was extracted from biopsy samples by the QIAgen kit. The PCR was performed for detection of cagA, cagE and cagT in cagPAI. Results: Among 80 H. pylori strains, 20 (25%) and 60 (75%) were isolated from PUD and NUD patients respectively. In PUD patients with rate of 14 (70%), all of isolates were cagA positive and distribution of cagE was 7 (35%) and cagT was 5 (25%). Also the prevalence of cagA, cagE and cagT in NUD patients was 48 (80%), 21 (35%) and 22 (36%) respectively. Discussion: Our results indicated that presence of cag PAI is very common in Iranian strains of H. pylori. The structural variety of the cag PAI might be related to the virulence of H. pylori. Present study showed that the prevalence of cagT, a marker for cagII, in PUD patients is less than NUD patients. In cagI region the presence of cagA in PUD patient is higher than cagE, so it may have an important role in peptic ulcer disease. According to our results it seems that it is not absolutely necessary to coexist of cagII and cagI in peptic ulcer patients.

Relationship Between Helicobacter pylori BabA and BabB Status with Other Virulence Factors and Their Correlation with Disease Outcome in Iran

Objectives: Helicobacter pylori (Hp) is an important human pathogen associated with gastrointestinal diseases such as gastritis, peptic ulcer disease (PUD) and gastric cancer. A number of pathogenic factors have been described for this bacterium, and some of them have been proposed as predictive markers of the clinical outcomes. However, with the exception of the cag and vacA status, there is no global consensus regarding the role of the other introduced virulence factors. Therefore, the aim of this study was to investigate the status of Hp strains regarding the Hp babA and babB (blood group antigen binding) adhesins and assess any existing association between the status of these genes and clinical outcomes in Iranian patients. Methods: Hp virulence genes were amplified by means of gene-specific polymerase chain reaction in clinical isolates of Hp from 72 Iranian patients (16 GC, 12 PUD, 44 NUD patients). Results: Eleven categories of genotypes were identified with the following frequencies: Group1: A+B+/cagA+/s1(38.0%); Group2: A+B+/cag+/s2(2.8%); Group3: A+B+/cag-/s1(1.4%); Group4: A+B-/cag+/s1(7%); Group5: A+B-/cag+/s2(2.8%); Group6: A-B+/cag+/s1(22.5%); Group7: A-B+/cag+/s2(14.1%); Group8: A-B+/cag-/s1(1.4%); Group9: A-B+/cag-/s2(4.2%); Group10: A-B-/cag+/s1(2.8%); Group11: A-B-/cag+/s2(2.8%). Frequency of Group1 in GC, NUD and PUD patients is 75%, 27.3% and 27.3% respectively and Group7 is prevalent in 36.4% of PUD patients. babA prevalence in GC, NUD and PUD patients was 75%, 47.7% and 33.3% and babB prevalence was 93.8%, 77.3% and 91.7% respectively. 75% of Hp isolates were babA/babB double positive in GC patients. Conclusion: Frequency of babB is higher among Iranian GC and PUD cases but babA frequency is limited to GC cases. Infecting strains from Groups 1 and 7 were found to be associated with GC and PUD respectively. Co-presence of cagA, s1vacA, babA and babB may work synergistically in exacerbating the resulting inflammation which may create grounds for development of intestinal metaplasia and eventually GC, whereas co-existence of cagA, s2vacA, babB may cause susceptibility to PUD development. In GC cases presence of babA/babB double positive are significantly prevalent (p = 0.044). Application of this analysis on additional samples will allow for a more concrete conclusion.

Helicobacter Pylori Diversity in Gastric Cancer and GERD Among Singapore Chinese Population

Introduction: H.pylori (Hp) infection leads to divergent clinical outcomes like PUD, chronic gastritis, gastric cancers (GC) and GERD. Bacterial factors, host factors, combination of both and environmental factors play major role in establishing the disease. We hypothesize that diverse genetic factors cause GC and GERD in our population. Aim: To determine various genotypes associated with GC and GERD among Singaporean Chinese population. Materials & Methods: H.pylori was cultured from 182 Chinese patients (52GC, 70 gastritis & 60 GERD) were analyzed in this prospective, on-going study. DNA was extracted, sequence analysis and genotyping was performed using specific gene primers of various virulence factors such as cagPAI, vacAs1, s2, m1, m2, cagE, babA2, sabA and oipA. Results: Univariate and multivariate analysis revealed that cagPAI, cagE, babA2, sabA and oipA were significant among GC when compared with gastritis (p < 0.001). oipA “on” status was significantly associated with expression of cagPAI and suppression of sabA (p < 0.01). Sequence analysis of representative Hp strains indicated that cagPAI, cagE, babA2, sabA and oipA oipA exhibited >92% identity to previously published data. Univariate analysis of GERD revealed that cagE, babA2 and oipA were significant (P < 0.01), whereas, multivariate analysis revealed that none of the genotypes were significant. Conclusion: Our on-going, prospective study indicates that Hp genetic diversity is related to clinical presentation. Virulence factors associated with GC were: CagPAI, CagE and outer membrane proteins (SabA, OipA, babA2). Host factors may have a moderating role in the clinical manifestation of Hp infection. Majority of oipA genotype is detected at functional status. The “on” status was significantly related to gastric cancer. This could probably be associated with enhanced interleukin-8 secretion and inflammation, important at initial stages of disease process. Further studies will be focused on measurement of levels of interleukin, OipA proteins or anti-OipA antibody in patients' sera, pathological assessment & oipA functional status and disease presentation. Hp strains from GERD patients did not significantly express any of the genotypes when compared to NUD patients. Our study suggests these genotypes may protect against the development of GERD in our population.

Cag PAI in H. pylori Isolated from Dyspeptic Patients in Tehran, Iran

Purpose: The aim of this study was to investigate the prevalence of cagPAI in H. Pylori isolated from gastritis patients in Tehran, Iran. Methods: A total of 70 H. pylori strain with positive PCR results for glmM gene were selected from dyspeptic patients in Tehran, Iran. DNA extraction from biopsies was performed by QIAamp® DNA Mini Kit (QIAGEN GERMAN). PCR amplification was used for four loci (cagA, cagG, cagM, cagT) of cag PAI. Results: Out of 70 biopsy samples with glmM-positive gene, cagA were detected in 74.3% (52 of 70) of patients. The prevalence of cagT, cagG genes were 15%, 10% respectively. cagM gene was not detected in studied isolates. Co-existence of cagA/cagT, and cagA/cagG were detected in 12 and 7 isolates respectively. We detected 6 H. pylori isolates with cagA negative; however they carried either cagG or cagT genes. There were 4 isolates which had three genes (cagA/cagG/cagT) together. Conclusion: The pathogenic role of the cag PAI as a whole or in part, in disease development, is not yet completely understood. Although the most studies were reported that there are correlations between genotyping of cagPAI and PUD or GC. Finding of this study showed all of isolates from NUD patients were carried at least one of cagG/cagT/cagA genes. According to result, the cagA gene could be served as a better marker for the cag PAI. However, the presence of this single gene does not necessarily indicate the presence of a complete set of cag PAI genes. Low prevalence of PUD samples may relate to lack of cagM, whose product is essential for type IV secretion system. At the end we suggest studding of more genes of cagPAI in patients with PUD and gastric cancer in large population.

Clinical Outcomes of Helicobacter pylori Infection in Relation to vacA and cagA Genotypes in Iranian Patients

Purpose: The aims of this study were to evaluate the role of vacA genotyping with respect to gastric inflammation and injury, and clinical presentation in Iranian populations. Methods: Genomic DNA from biopsy specimens from patients with gastritis, peptic ulcer disease and gastric cancer were characterized by ureC (glmM), cagA and vacA genotyping by polymerase chain reaction (PCR). Results: Our results showed that 96 (57%) of 167 patients with gastro duodenal diseases, 19 of 33 gastroduodenal ulcer and 3(60%) of 5 gastric cancer were infected with H. pylori. In this study 19.8% strains were isolated from patients with PUD and 68.7% from patients with NUD.s1m2 genotype was observed in 36.8%, of PUD and 40.5% NUD patients. Conclusion: Prevalence of cagA positive (76%) in Iran is close to that of Europe and North America (60–70%) than Asian countries (90%). Regarding the vacA gene, 97% (93 of 96) of H. pylori positive patients determined by ureC (glmM) PCR were successfully detect the vacA gene. The vacA s1m2 was predominant genotype in Iran (41%). The prevalence of s2m1 (8.3%) was high in Iranian isolates. Although individuals who infected with H. pylori possessing the cagA (+) gene and vacA m2 genotypes were more sensitive to development of gastroduodenal disease but we could not find any significant correlation between cagA status and PUD, because of similar high cagA gene positivity in the H. pylori strains isolated from PUD (78.6%) and NUD (74.3%). CagA status cannot be used as a useful marker to predict the outcome of the infection in patients in Iran.

Diagnostic Utility of Invasive Tests and Serology for the Diagnosis of Helicobacter pylori Infection in Different Clinical Presentations

Invasive and noninvasive tests are used for the diagnosis of Helicobacter pylori infection. The aim of this study was to determine the diagnostic utility of rapid urease test (RUT), culture, histology and serology for the diagnosis of H. pylori in patients with different clinical presentations. We studied 527 consecutive patients (mean age, 52.5 years; F:M, 1.3; age range 15-89 years) enrolled at the Hospital Universitario, Universidad Autónoma de Nuevo León. Patients had gastric cancer (GC, 9.1%), non-ulcer dyspepsia (NUD, 81.4%), or peptic ulcer disease (PUD, 9.1%). The infection by H. pylori was determined by histology, rapid urease test, culture, and serology. Patients were determined as infected with H. pylori if at least a) two invasive tests were positive and b) two tests were positive (invasive or non-invasive). Diagnostic utility was calculated for each assay. Prevalence of infection in the whole studied population was 50.9%. In NUD patients the prevalence was 51.3%, in PUD patients 58.3%, and in GC patients 39.6%. When we used the first diagnostic criteria, for the whole studied population, the RUT was the most reliable test, followed by the culture. Histology had the best sensitivity for the whole studied population and NUD patients and RUT had the best sensitivity value for the GC patients. In the whole studied population, NUD and GC patients, RUT and culture had the best specificity, accuracy and PPV. For PUD patients, serology had the best performance. When we used the second diagnostic criteria, histology and serology had a better performance compared with the results obtained with the first diagnostic criteria. Diagnostic utility of the tests varies according to the clinical presentations, which should be considered in the selection of the diagnostic test for the detection of H. pylori.

Helicobacter pylori Endemic and Gastric Disease

H. pylori infection of the stomach is widespread among human populations including Iranians and is considered to play a major role in the pathogenesis of gastric diseases such as peptic ulcer, adenocarcinoma, and MALT lymphoma. The association between H. pylorivirulence markers and disease has been studied in other populations around the world. The aim of this study was to investigate the distribution of H. pylori vacA and cagA genotypes and their association with clinical outcomes in Iran. H. pylori was cultured from gastric biopsy specimens obtained from 137 Iranian patients (58 with duodenal ulcer, 61 with nonulcer dyspeptic [NUD], and 18 with gastric adenocarcinoma). The vacA alleles and cagA genotypes were determined by PCR. The vacA sl allele was present in 107 of the 137 subjects (78%). Multiple strains (m1 and m2) were detected in H. pylori isolates from the patients. VacA s1 genotypes were more frequent in patients with peptic ulcer (46/58; 79%) than in NUD patients (47/61; 77%). CagA was present in 44% of the patients. NUD patients had a frequency of cagA positivity similar to that of the overall population (46%). CagA was present more frequently more than cagA-negative (20% vs. 8%, respectively) in patients with gastric carcinoma (20%) than cagA-negative in patients with gastric carcinoma (8%). This is the first comprehensive study to demonstrate the frequency of colonization with mixed strain, vacA s1, m1 and m2 as the dominant genotype in these Iranian patients, where a high rate of H. pylori infection exists and is similar to the region with a low rate of H. pylori infection. Therefore, host genetics, environmental factors, and the substantial genetic heterogeneity among different H. pylori strains may contribute to the different clinical outcomes.

Down-Regulation of Secretory Leukocyte Protease Inhibitor Expression in Gastric Mucosa Is a General Phenomenon in Helicobacter pylori-Related Gastroduodenal Diseases

Background: Secretory leukocyte protease inhibitor (SLPI) represents a multifunctional protein of the gastric mucosa exerting anti-microbial and anti-inflammatory effects. Recently, a local down-regulation of antral SLPI expression in Helicobacter pylori (Hp)-infected healthy volunteers was demonstrated. Aim: To analyze mucosal SLPI expression in patients with various gastroduodenal disorders. Methods: The prospective study included 90 patients with following gastroduodenal disorders diagnosed: gastric cancer (GC, n = 22), duodenal ulcer (DU, n = 17), Hp-positive dyspeptic patients (NUD, n = 31) and Hp-negative NUD (n = 20). During esophagogastroduodenoscopy, biopsies were taken each from antrum, corpus and tumor. SLPI expression was analyzed by quantitative RT-PCR and ELISA. Results: Antral SLPI levels were reduced in all Hp-infected patients (NUD, DU, GC) by about 75% (1,494–1,826 pg/50 µg protein) compared to Hp-negative NUD (6,563 pg/50 µg protein, p < 0.001, ANOVA). Tumor tissue had twofold higher SLPI levels than surrounding tumor-free gastric mucosa (3,900 vs. 1,826 pg/50 µg protein, p = 0.013), but revealed reduced SLPI levels compared to Hp-negative NUD patients (p = 0.067). No differences were found between SLPI expression of intestinal and diffuse GC. SLPI transcript levels were unchanged throughout all groups and locations implying that transcriptional regulation of SLPI is not involved. Conclusion: Local down-regulation of SLPI in antral mucosa is a general phenomenon of Hp-related diseases.

Characteristics of Helicobacter pylori-induced gastritis and the effect of H. pylori eradication in patients with chronic idiopathic thrombocytopenic purpura.

The association between Helicobacter pylori infection and idiopathic thrombocytopenic purpura (ITP) has been reported widely. We investigated the prevalence of H. pylori infection, its virulence profile and the effectiveness of its eradication in patients with ITP. Twenty patients with ITP, 20 with peptic ulcer (10 gastric ulcer (GU), 10 duodenal ulcer (DU)) and 20 with NUD were studied. The virulence profile of the strains was assessed by genotyping for cagA, vacA, iceA, and hpyIIIR/hrgA and by assaying for IL-8 and DNA fragmentation after incubation with AGS cells. Infected patients and two uninfected ITP patients received triple therapy and platelets were counted before and 1 month, 6 months, 1 year, and 2 years after eradication therapy. H. pylori infection was found in 17 ITP (85%), 20 ulcer (100%) and 13 NUD (65%) patients. Biopsies and strains were collected from five ITP, 20 ulcer and 13 NUD patients. The ITP patients had a pangastritis or corpus-predominant gastritis pattern. All H. pylori isolates, from ITP, ulcer and NUD patients, were cagA(+) and vacA s1/m1, and did not differ in levels of IL-8 induction or DNA fragmentation. Fifteen ITP (88%) and 17 ulcer (85%) patients had successful eradication of H. pylori. Ten of these 15 (67%) H. pylori-eradicated ITP patients had platelet recovery. There was no significant change in platelet count in the two ITP patients in whom eradication failed or in the two originally H. pylori-uninfected ITP patients, or in the treated ulcer patients. Age at onset of ITP was the main determinant of platelet recovery: 100% of patients diagnosed after the age of 60 recovered compared with only 22% of those diagnosed before 50. H. pylori-infected ITP patients have a corpus-predominant pattern of gastritis but the virulence profile of their strains does not differ from that of ulcer or NUD patients. Eradication of H. pylori infection is a good therapeutic option for some patients with chronic ITP, especially for those who develop ITP in older age.

Clarithromycin resistance, but not CYP2C-19 polymorphism, has a major impact on treatment success in 7-day treatment regimen for cure of H. pylori infection: a multiple logistic regression analysis.

Mutations in the gene encoding the CYP2C-19 enzyme for PPI metabolism have been shown to enhance the chance for a cure in a H. pylori-positive patients using a two-week dual-therapy regimen involving omeprazole and amoxicillin. However, the impact of CYP2C-19 genetic polymorphism on eradication rates of a one-week triple-therapy regimen has not been examined. In this cohort study, 156 H. pylori-positive peptic ulcer or NUD patients who presented to our university hospital were recruited. They were treated by one-week omeprazole-amoxicillin-clarithromycin therapy. Host and bacterial predictive factors including H. pylori susceptibility and CYP2C-19 genotyping, as well as cure rate for H. pylori infection, were studied. Cure rate was 85.9% (95% CI: 79-91%) on an intent to treat (ITT) basis. By multiple logistic regression analysis, only clarithromycin resistance had a significant impact on treatment success (odds ratio 28.7: 95% CI: 6-172). CYP2C-19 genetic polymorphism was not associated with a significant change in cure rate. These observations indicate only clarithromycin susceptibility, not CYP2C-19 polymorphism, has a major impact on the treatment success when using a seven-day OAC H. pylori treatment regimen.

CORRELATION OF PRESENCE OF H. PYLORI WITH HISTOLOGICAL AND SYMPTOMATIC SCORE IN PATIENTS WITH NON ULCER DYSPEPSIA (NUD)

BackgroundNon ulcer dyspepsia (NUD) is being postulated as one of the gastroduodenal manifestations of H. pylori infection. H. pylori infection may result in clinical symptoms as well as histological changes in (NUD).AimTo compare clinical symtoms score and histological changes in H. pylori (Hp) positive and negative untreated NUD patients.MethodsPatients with dyspeptic symptoms and abnormal UGI endoscopic examination were included in the study. During endoscopy 2 biopsies each were taken from antrum and corpus. These biopsies were used for rapid urease test (RUT) and histological evaluation. There were 2 group: Hp positive and Hp negative NUD patients. Patients were diagnosed to have H. pylori infection of either of the two test (RUT, histology) were positive. Clinical scoring using glasglow dyspepsia score (max 20) and histological analysis using Sydney system (max score 11) was done and compared for both the groups. Clinical scoring RUT &amp; histological scoring were blinded to each other.Resultsto patients (29 Hp + and 17 Hp ‐ve) were enrolled in the study. The results in both groups were: Hp +ve Hp ‐ve P value Glasgow clinical score 10.9 11.4 ns Chr. Gastritis Antrum 89.6% 94.1% ns Corpus 93.1% 76.1% ns Activity Antrum 41.3% 41.1% ns Corpus 41.1% 29.4% ns Lymphoid follicles Antrum 34.4% 11.7% ns Corpus 37.9% 5.8% P &lt; 05 Atrophy Antrum 24.1% 11.7% ns Corpus 20.6% 11.7% ns Int. Metaplasia Antrum 13.7% 5.8% ns Corpus 10.3% 0% ns Total Histological Antrum 3.37 1.76 0.0003 Corpus 3.68 1.29 0.0001 ConclusionClinical scoring does not correlate with presence of H. pylori or the histological severity. In NUD patients positive for H. pylori, there is a significant increase in the severity of gastritis both in the antrum and the corpus.

Helicobacter pylori Infection: Protection against Barrett’s Mucosa and Neoplasia?

Background: Since Helicobacter pylori (Hp) infection provokes intestinal and gastric metaplasia, the question arises whether the specialized metaplasia (Barrett’s mucosa (BM)) and dysplasia or carcinoma in Barrett’s epithelium seen in gastro-oesophageal reflux disease (GORD) might not also be correlated with Hp infection, or whether the latter offers protection against Barrett’s oesophagus and Barrett’s adenocarcinoma. Patients: Gastric and oesophageal biopsies obtained from a total of 2,201 patients were analysed retrospectively. 297 of these patients had GORD (age 53.5 ± 13.4 years; m:f ratio 2.1:1), 1,192 patients had BM (age 62.8 ± 14.6 years; m:f 2.3:1) with or without neoplasia. 1,054 of these patients were diagnosed as having BM alone, 138 patients having BM neoplasia (high-grade dysplasia or adenocarcinoma). Patients with BM and low-grade dysplasia were excluded from this study because of the uncertainty in differentiating low-grade dysplasia from regenerative epithelium. A total of 712 patients with non-ulcer dyspepsia (NUD; average age 40.0 ± 16.1 years; m:f 0.3:1) served as a control group. Results: The percentage of Hp infection did not differ between patients with GORD with (53.3%)/without BM (51.4%) and neoplasia (47.8%), but is statistically significantly lower than in patients with NUD (65.7%). Conclusion: Our analysis shows that patients with GORD and Hp infection have no increased risk for the development of BM or neoplasia in BM. Since Hp infection is significantly less frequent in GORD than in NUD patients, a protective effect of the Hp infection is a possibility worth discussing.

A novel real-time quantitative PCR assay for detection of Helicobacter pylori in the gastric mucosa

BACKGROUND: Although the assessment of the density of Helicobacter pylori (H. pylori) colonization may be important, precise quantitative evaluation of H. pylori in the gastric mucosa has been difficult. We have developed a novel real-time quantitative PCR technique based on 5' -3' exonuclease assay for detection of H. pylori. Using this system, we evaluated number of H. pylori organisms present in gastric biopsy specimens. METHODS: A primer pair for PCR amplification was made according to the reported sequence of ureA gene of H. pylori, and an oligonucleotide probe labeled with two fluorescent dyes (a reporter dye at the 5' end and a quencher dye at the 3' end) was also designed. While the probe is intact, the quencher dye greatly reduces the fluorescent signal by the reporter dye (Fluorescence resonance energy transfer phenomenon). During the PCR extension phase, the annealed probe is cleaved by 5' -3' exonuclease activity of Taq DNA polymerase, increasing the reporter dye signal. The reporter dye signal during a PCR assay was monitored with a ABI PRISM 7700 Sequence Detector (Perkin-Elmer). Purified PCR products of ureA gene were used as standard samples for making standard curves plotting log starting copy number and threshold cycle (Ct: PCR cycle number at which the reporter fluorescence signal reached above baseline). Biopsy specimens were collected from antral mucosa of consecutive 32 patients underwent gastroscopy (GU 9, DU 9, GC 1, NUD 13). Three biopsy specimens were obtained from each patient to avoid the effect of patchy distribution of H. pylori. DNA was extracted by conventional phenol-chloroform method. Since the size of each biopsy specimen was variable, quantitative PCR assay described above was performed using 0.5 ~tg of DNA extracted from each sample. !~_!LL_.T~: In each amplification reaction, a liner standard curve could be generated in a wide range of starting copy numbers (6xl07 to 6xl0 copies of the target sequences, R 2 > 0.99). Nine of 32 samples (DU 2, NUD 7) showed no increase in the fluorescence signal during PCR process, indicating the absence of H. pylori, which was also confirmed by histological examinations. In H. pylori positive patients, the detected ureA copy numbers (i.e. number of H. pylori organisms) were variable among patients (range 1.4x102 1.2x105 copies/0.5Mg DNA, mean 2.6x104 copies/0.51ag DNA). The average ureA copy numbers of samples from DU and GU patients were not significantly different from that of NUD patients [GU (2.1 _+ l.l)xl04, DU (1.8 _+ 0.6)xl04, NUD (2.6 + 1.1)xl04 copies/0.51ag DNA, respectively]. The sample of one GC patient showed high density of H. pylori colonization (1.2x105 copies/0.5Mg DNA). CONCLUSIONS: Accurate quantitation of H. pylori in biopsy specimens was possible with this PCR system, and it will be useful for 1-1. pylori research.

Epidermal Growth Factor and Transforming Growth Factor Alpha in Duodenal Ulcer and Non-Ulcer Dyspepsia Patients before and after Helicobacter pylori Eradication

Background

Duodenal ulcer, Helicobacter pylori, and gastric secretion.

Patients with chronic dyspepsia were categorised by macroscopic appearance at oesophagogastroduodenoscopy as having duodenal ulceration (DU), other diagnosed lesions such as reflux oesophagitis, carcinoma of stomach, etc, or no organic lesion (non-ulcer dyspepsia, NUD). Material was collected to identify gastric infection with Helicobacter pylori (H pylori) by CP urease test, culture, and histological examination and to make the microscopic diagnosis of active chronic gastritis. Each patient in the DU and NUD categories was then invited to volunteer for a gastric secretion study in which maximal gastric secretion in response to histamine was measured. Sixty two gastric secretion tests were performed (31 DU, 31 NUD). The presence of H pylori was associated with active chronic gastritis (100%). DU patients secreted more acid than the NUD patients. H pylori positivity was associated with decreased maximal gastric secretion in both groups. There was a positive correlation between smoking and maximal acid output shown only in H pylori negative but not in H pylori positive patients. These findings were clear cut when all corrections of maximal gastric secretion were made for pyloric loss, duodenogastric reflux, and stature. This study failed to show any aetiological link between H pylori and DU by increased maximal gastric secretion.

STUDY OF THE ELECTRICAL ACTIVITY OF THE STOMACH IN CHILDREN WITH NON—ULCER DYSPEPSIA (NUD)

Gastric contractions are coordinated by slow waves (SW), an omnipresent oscillating electrical potential, that emanate from the orad stomach and migrate distally at 3 cycles/min (cpm) in man. We wished to determine prevalence of gastric electrical abnormalities in children with NUD, that is characterized by recurrent vomiting, epigastric pain and bloating, early satiety, without structural or focal GI tract lesions. Eleven NUD patients (pts) (mean±SD age: 6.9±3.4 years) underwent cutaneous recording of gastric SW by electrodes (Red Dot 2256, 3M Co) located on the gastric region, for 1 hour before and after feeding a 300 cal mixed solid liquid meal (bread, egg, apple juice). Electrogastrograpny (EGG) signals were recorded on a Reega Minihuit Tr Alvar polygraph (lower and upper cutoff frequencies: 0.16 Hz and 30 Hz respectively) and later digitized on HP3852A and stored on HP Vectra RS80 for spectral analysis. Results: during fasting, 7 pts (group A) had significant electrical dysrhythmias (≥ 10% of the recording period) such as tachygastria (SW between 4 and 9 cpm, with regular rhythm), tachyarrhythmia (SW between 4 and 9 cpm with irregular rhythm), bradygastria (SW < 3 cpm), or flatline patterns; most dysrhythmic periods were coincident with dyspeptic symptoms such as nausea, epigastric pain and vomiting. In 4 pts (group B) electrical abnormalities were rarely detected, as well as in 5 age matched controls (7.1± 3.7 years). After feeding, only 3 group A pts had marked dysrhythmias. In all group A pts, antro-duodenal manometry, performed by perfused catheter, showed severe motor changes such as fasting and/or fed decreased and/or incoordinated gastrointestinal motility; no disturbed motility was recorded in group B pts. Furthermore, gastric emptying time (min.) (mean±SD), measured by ultrasonography after eating the same meal administered during EGG, was much more delayed in group A pts (187±45.3; range: 130-250) than in B group pts (100±13; range: 85-116). He conclude that gastric electrical abnormalities are found in a substantial proportion of children with non-ulcer dyspepsia. Our preliminary results support the hypotesis that gastric dysrhythmias can be the electrical counterpart of gastroduodenal motor abnormalities frequently detected in patients with NUD.