Helicobacter pylori Infection and Gastric Autoimmune Diseases: Is There a Link?

Background. Helicobacter pylori is thought to be involved in atrophic body gastritis. We explored the prevalence of H. pylori infection in asymptomatic subjects with gastric parietal cell antibodies, as well as in patients with pernicious anemia, to evaluate a possible role of H. pylori gastric infection in gastric autoimmunity. Patients and Methods. We studied 79 consecutive asymptomatic subjects with parietal cell antibodies, 24 patients with pernicious anemia, and 66 parietal cell antibody‐negative controls. All patients underwent gastric biopsies for histology and detection of H. pylori. Red blood cell count and volume, serum levels of gastrin, pepsinogen I, iron, folic acid, vitamin B₁₂, and circulating antibodies to H. pylori and to intrinsic factor were also determined. Results. We found an atrophic body gastritis in 14 of the 79 asymptomatic subjects with parietal cell antibodies (18%) and in 2 of the 66 controls (3%) (p = .01). Mean levels of gastrin were increased (p < .0001), while those of pepsinogen were reduced (p < .001) compared with controls. H. pylori was identified at the gastric level and/or circulating anti‐H. pylori antibodies were detected in 46 parietal cell antibody‐positive subjects (58%) compared with 26 controls (39%) (p = .03). In patients with pernicious anemia we found an atrophic body gastritis in 18 of 24 cases (75%) (p < .001 vs. controls). Mean levels of gastrin were markedly increased (p < .0001) and those of pepsinogen I decreased (p < .0001) relative to controls. Only five of these patients (21%) had evidence of H. pylori infection compared with 46 of the parietal cell antibody‐positive subjects (58%) (p = .003) and 26 of the controls (39%). Considering all patients with gastric autoimmunity (i.e. with parietal cell antibodies and/or with pernicious anemia), H. pylori was found in 44 of 72 of those without atrophy (61%) but in 6 of 31 with gastric body atrophy (19%) (p < .001), indicating that H. pylori infection is greatly reduced when gastric acid secretion decreases. Conclusions. The frequent detection of H. pylori infection in subjects with early gastric autoimmunity, indicated by the presence of parietal cell antibodies, suggests that H. pylori could have a crucial role in the induction and/or the maintenance of autoimmunity at the gastric level.     

Is the Association Between Helicobacter pylori Infection and Anemia Age Dependent?

Background: The relationship between H. pylori infection and anemia in childhood is still unclear. The aim of the study was to examine the association between H. pylori infection and anemia or iron deficiency in school‐age children and in infants. Materials and Methods: Six‐ to 9‐ year‐old Israeli Arab children (N = 202) and infants (N = 197) were examined for hemoglobin and ferritin levels. ELISA was used to detect H. pylori antigens in stool specimens collected from the participants. Household characteristics were obtained through personal interviews with the mothers. Results: The prevalence of anemia was 15.5 versus 5.5% in H. pylori‐positive and ‐negative school‐age children, respectively and 34.5 versus 29.8% in H. pylori‐positive and ‐negative infants, respectively. The Mantel–Haenszel age‐adjusted prevalence ratio (PR) and 95% confidence intervals (CIs) were 1.6 (95%CI 1.0, 2.6). In multivariate analysis controlling for socioeconomic variables, H. pylori infection was associated with 2.8 higher prevalence of anemia only in school‐age children: adjusted PR 2.8 (95% CI 0.9, 9.3). The adjusted mean difference in hemoglobin levels between H. pylori infected school‐age children and uninfected ones was ?0.372 gr/dL (95% CI ?0.704, ?0.039) (p = .04). The respective mean ferritin difference was ?6.74 μg/L (95% CI ?13.38, ?.011) (p = .04). Such differences were not found in infants. Conclusions: H. pylori infection is associated with higher prevalence of anemia in school‐age children independently of socioeconomic variables. Such association was not observed in infants. These findings are of clinical and public health importance.     

Do women with acute myocardial infarction receive the same treatment as men?

OBJECTIVE--To determine whether women with acute myocardial infarction in the Nottingham health district receive the same therapeutic interventions as their male counterparts. DESIGN--Retrospective study. SETTING--University and City Hospitals, Nottingham. PATIENTS--All patients admitted with a suspected myocardial infarction during 1989 and 1990. MAIN OUTCOME MEASURES--Route and timing of admission to hospital, ward of admission, treatment, interventions in hospital, and mortality. RESULTS--Women with myocardial infarction took longer to arrive in hospital than men. They were less likely to be admitted to the coronary care unit and were therefore also less likely to receive thrombolytic treatment. They seemed to have more severe infarcts, with higher Killip classes, and had a slightly higher mortality during admission. They were less likely than men to receive secondary prophylaxis by being discharged taking beta blockers or aspirin. CONCLUSIONS--Survival chances both in hospital and after discharge in women with acute myocardial infarction are reduced because they do not have the same opportunity for therapeutic intervention as men.     

Is Helicobacter pylori a True Microaerophile?

BACKGROUND: There is no general consensus about the specific oxygen and carbon dioxide requirements of the human pathogen Helicobacter pylori. This bacterium is considered a microaerophile and consequently, it is grown under atmospheres at oxygen tensions 5-19% and carbon dioxide tensions 5-10%, both for clinical and basic and applied research purposes. The current study compared the growth of H. pylori in vitro, under various gas atmospheres, and determined some specific changes in the physiology of bacteria grown under different oxygen partial pressures. METHODS: Measurements of bacterial growth under various conditions were carried out employing classical solid and liquid culture techniques. Enzymatic activities were measured using spectrophotometric assays. RESULTS: H. pylori and all the other Helicobacter spp. tested had an absolute requirement for elevated carbon dioxide concentrations in the growth atmosphere. In contrast with other Helicobacter spp., H. pylori can tolerate elevated oxygen tensions when grown at high bacterial concentrations. Under 5% CO(2), the bacterium showed similar growth in liquid cultures under oxygen tensions from microaerobic (< 5%) to fully aerobic (21%) at cell densities higher than 5 x 10(5) cfu/ml for media supplemented with horse serum and 5 x 10(7) cfu/ml for media supplemented with beta-cyclodextrin. Evidence that changes occurred in the physiology of H. pylori was obtained by comparing the activities of ferredoxin:NADH (nicotinamide adenine dinucleotide) oxidoreductases of bacteria grown under microaerobic and aerobic atmospheres. CONCLUSIONS: H. pylori is a capnophile able to grow equally well in vitro under microaerobic or aerobic conditions at high bacterial concentrations, and behaved like oxygen-sensitive microaerophiles at low cell densities. Some characteristics of H. pylori cells grown in vitro under microaerobic conditions appeared to mimic better the physiology of organisms grown in their natural niche in the human stomach.     

Genetic variation between Helicobacter pylori strains: gene acquisition or loss?

Previously identified strain-specific genes of Helicobacter pylori were analysed for GC content and preference in codon usage. The results indicate that in H. pylori strain specificity is mainly driven by gene uptake. Incoming strains of Helicobacter or other species can occasionally donate genes but the identification of the donor species is hampered by ongoing evolutionary processes and the lack of an adequate number, or indeed a total absence, of gene homologues.     

Histological Classif ication of Gastritis and Helicobacter pylori Infection: An Agreement at Last?

An international workshop has assessed and revised the Sydney System for the reporting of gastritis. Much of the original approach was retained including division into acute , chronic and special forms, and grading of chronic inflammation, polymorph activity, atrophy, intestinal metaplasia and H. pylori density into mild, moderate and marked categories. Visual analog scales have been introduced as a simple guide to grading. The four biopsy sites have been changed to optimize detection of H. pylori , and supplemented by a fifth biopsy from the incisura angularis, the site which is most likely to yield premalignant changes. Chronic gastritis is classified into non-atrophic and atrophic forms with the latter divided into autoimmune (diffuse corpus atrophy) and multifocal . Histological reporting of gastritis should take into account the topographical pattern ( antral or corpus predominant ), and the final diagnostic term should ideally combine morphology and etiology to maximize the clinical value of gastric biopsy diagnosis.     

Is Sudden Infant Death Syndrome Associated with Helicobacter pylori Infection in Children?

Helicobacter pylori infection has recently been implicated in the pathogenesis of sudden infant death syndrome (SIDS). We investigated this association. Twenty-five pairs of gastric and tracheal tissue specimens obtained from autopsies of 25 children with previous diagnoses of SIDS were available for this study. The presence of H. pylori organisms was evaluated by three different methods: histology (hematoxylin-eosin or Giemsa staining), immunohistochemistry, and nested polymerase chain reaction technique. We were unable to confirm the presence of H. pylori organisms by the first two methods. H. pylori DNA was identified by nested polymerase chain reaction in six different tissue specimens (stomach, 4; trachea, 2). In no case was H. pylori DNA detected in both tissues. We concluded that H. pylori infection is most likely not associated with SIDS.     

Helicobacter pylori gastritis: a Th1 mediated disease?

Helicobacter pylori is now considered to be the main cause for most stomach diseases including ulcer, MALT lymphoma, adenocarcinoma and gastritis. The infection with this bacterium is chronic despite a local and systemic immune response towards it. Among the cellular infiltrate that arises during H. pylori-mediated gastritis, there is a considerable frequency of CD4+ Th1 cells producing IFNgamma, but not of Th2 cells producing IL-4. Since IFNgamma may induce binding of H. pylori to gastric epithelial cells followed by apoptosis of these cells, one may speculate that H. pylori-mediated diseases are in part autoimmune diseases initiated by H. pylori-specific Th1 cells infiltrating the gastric mucosa. Recent support for this hypothesis comes from an animal model in which mice are infected with H. pylori and display strongly reduced gastritis in the absence of IFNgamma.     

Heights and weights of Da-an boys: did sisters really make a difference?

This study further examined the negative association between boys' growth and the presence of sisters within a relatively affluent community in Taipei, Taiwan. Among 596 boys born in 1976-77, differences in height and log-transformed weight were judged using analysis of covariance (ANCOVA) with measurement age as a covariate, and parental education level (four levels), number of sisters (0, 1, 2 or 3+) and number of brothers (0, 1, 2+) as predictors. The relative importance of birth order and sibling sex was examined among the near majority of boys with one sibling (47%, 278/596). The sibling composition variable was defined using mutually exclusive categories representing individuals with one sibling: either one older or younger brother or sister. All boys contributed information before leaving middle school at a mean age of 14.9 +/- 0.4 years SD. The results were compared with similar analyses of data for 154 of these same boys for whom measurements were available from primary school entry at a mean age of 64 +/- 0.3 years SD onward. Results were also compared with data for a cohort of 153 boys who entered primary school later in 1986. Results confirm that boys from the Da-an area born in the mid-1970s who did not have sisters were significantly taller (2.2-2.5 cm, p < or = 0.008) and heavier (3.0-3.9 kg, p < or = 0.016) than those with one or two sisters. However, the 26 boys with three or more sisters, most of whom were last-born, were somewhat taller than those with one or two sisters. The same curvilinear relationships in height and weight appeared both among boys as they prepared to leave middle school and among the subset also measured just after entering primary school. When numbers of sisters were statistically controlled, the presence of two or more brothers was also significantly negatively associated with mean stature, but not weight, among middle school boys. Analyses among boys with one sibling revealed that birth order was associated with mean stature, but only if the sibling was female; an older sister was associated with a greater deficit in mean stature than a younger sister. Evidence of rising educational expectations, continued declines in family size with fewer gender-related differences in numbers of siblings, and a clear secular increase in body size in this community among children entering primary school from 1982 to 1986 suggest a possible explanatory model.     

Do natural enemies really make a difference? Field scale impacts of parasitoid wasps and hoverfly larvae on cereal aphid populations

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Thrombolysis after acute myocardial infarction: Are Canadian physicians up to the challenge?

Acute myocardial infarction (AMI) evolves as a time-dependent wave front of ischemia when the abrupt rupture of an unstable fatty plaque initiates coronary thrombosis. The prospect of salvaging potentially viable myocardial tissue has led to the development of reperfusion strategies using thrombolytic agents. The efficacy of thrombolytic therapy is determined in large measure by the speed with which it is initiated. It is therefore vital to minimize the "door-to-needle" time once a patient with AMI arrives at the emergency department. In this issue (see pages 497 to 505) Dr. Jafna L. Cox and associates report that Canadian centres participating in the GUSTO-I trial were significantly slower to initiate thrombolytic therapy than their US counterparts. In this editorial Cox and associates'' report is reviewed against the background of similar trials, and strategies to minimize delays in the initiation of thrombolytic therapy are suggested.     

Oxidative Stress in Helicobacter pylori Infection: Does Supplementation with Vitamins C and E Increase the Eradication Rate?

Aim: This study aims to assess the antioxidant property of vitamins E and C in Helicobacter pylori infection, and to determine if adding them to standard triple therapy plus bismuth subcitrate increases the H. pylori eradication rate. Methods: This study included 160 patients infected with H. pylori, who were randomized into one of two groups. Patients in group A (n = 80) received lansoprazole (30 mg, b.i.d.), amoxicillin (1000 mg, b.i.d.), clarithromycin (500 mg, b.i.d.), and bismuth subcitrate (300 mg, q.i.d.) for 14 days, while patients in group B (n = 80) received vitamin C (500 mg, b.i.d.) and vitamin E (200 IU, b.i.d.) for 30 days, in addition to lansoprazole (30 mg, b.i.d.), amoxicillin (1000 mg, b.i.d.), clarithromycin (500 mg, b.i.d.), and bismuth subcitrate (300 mg, q.i.d.) for 14 days. Total antioxidant capacity (TAC) was evaluated with a Randox kit. Success rate was calculated using both intention‐to‐treat (ITT) and per‐protocol (PP) analyses. Results: One hundred and sixty patients were analyzed using ITT analysis. One hundred and fifty‐three patients completed the study. In group A, H. pylori eradication was achieved in 48 (60%) of the 80 patients included in the ITT analysis, and in 48 (64%) of the 75 patients included in the PP analysis. In group B, H. pylori eradication was achieved in 73 (91.25%) of the 80 included in the ITT analysis and in 73 (93.5%) of the 78 patients included in the PP analysis. The eradication rate was significantly higher in group B than in group A (p < .005). TAC was at the lower limit of normal in both groups and the difference between them was not statistically significant (p > .05). Conclusion: In group B, H. pylori eradication rate was 91.25%, which is higher than the ideal 80% eradication rate. The results of the present study show that adding the prescribed doses of vitamins E and C to antimicrobial therapy is effective in eradicating H. pylori infection.     

Gastric epithelial cell death caused by Helicobacter suis and Helicobacter pylori γ-glutamyl transpeptidase is mainly glutathione degradation-dependent

Helicobacter (H.) suis is the most prevalent non-H. pylori Helicobacter species colonizing the stomach of humans suffering from gastric disease. In the present study, we aimed to unravel the mechanism used by H. suis to induce gastric epithelial cell damage. H. suis lysate induced mainly apoptotic death of human gastric epithelial cells. Inhibition of γ-glutamyl transpeptidase (GGT) activity present in H. suis lysate and incubation of AGS cells with purified native and recombinant H. suis GGT showed that this enzyme was partly responsible for the observed apoptosis. Supplementation of H. suis or H. pylori GGT-treated cells with glutathione strongly enhanced the harmful effect of both enzymes and resulted in the induction of oncosis/necrosis, demonstrating that H. suis and H. pylori GGT-mediated degradation of glutathione and the resulting formation of glutathione degradation products play a direct and active role in the induction of gastric epithelial cell death. This was preceded by an increase of extracellular H(2)O(2) concentrations, generated in a cell-independent manner and causing lipid peroxidation. In conclusion, H. suis and H. pylori GGT-mediated generation of pro-oxidant glutathione degradation products brings on cell damage and causes apoptosis or necrosis, dependent on the amount of extracellular glutathione available as a GGT substrate.     

‘No-reflow’ after acute myocardial infarction: direct visualisation of microvascular obstruction by gadolinium-enhanced CMR

Cardiovascular magnetic resonance is considered the standard imaging modality in clinical trials to monitor patients after acute myocardial infarction. However, limited data are available with respect to infarct size, presence and extent of microvascular injury (MVO) and changes over time, in relation to cardiac function in optimally treated patients. In the current study we prospectively investigate the change of infarct size over time, and the incidence and significance of MVO in a uniform, optimally treated patient group after AMI. (Neth Heart J 2008;16:179-81.)