Helicobacter pylori and extragastric diseases

Research progress on Helicobacter pylori infection related neurological diseases

Helicobacter pylori, a type of gram-negative bacterium, infects roughly half of the global population. It is strongly associated with gastrointestinal disorders like gastric cancer, peptic ulcers, and chronic gastritis. Moreover, numerous studies have linked this bacterium to various extra-gastric conditions, including hematologic, cardiovascular, and neurological issues. Specifically, research has shown that Helicobacter pylori interacts with the brain through the microbiota-gut-brain axis, thereby increasing the risk of neurological disorders. The inflammatory mediators released by Helicobacter pylori-induced chronic gastritis may disrupt the function of the blood-brain barrier by interfering with the transmission or direct action of neurotransmitters. This article examines the correlation between Helicobacter pylori and a range of conditions, such as hyperhomocysteinemia, schizophrenia, Alzheimer's disease, Parkinson's disease, ischemic stroke, multiple sclerosis, migraine, and Guillain-Barré syndrome.

Assessment of histology's performance compared with PCR in the diagnosis of Helicobacter pylori infection

Aim: Histology is the most widely used test to detect H. pylori. PCR is less used but allows the detection of both infection and antibiotics' resistance. Methods: We conducted a monocentric cross-sectional study, collecting 97 symptomatic patients to assess the diagnostic performance of histology in the detection of H. pylori infection compared with PCR. Results: Sensitivity of histology in comparison with PCR was 81.5% and specificity was 56.3%. A history of anti-H. pylori therapy intake, as well as the density of the bacterium on the gastric sample and the presence of gastric atrophy, were significantly correlated to the PCR's result in terms of H. pylori detection. Conclusion: Thus, histology can be considered as an efficient test compared with PCR in H. pylori detection.

The prospective multiple-centre randomized controlled clinical study of high-dose amoxicillin-proton pump inhibitor dual therapy for H. pylori infection in Sichuan areas

OBJECTIVES

To evaluate the safety and efficacy of high-dose amoxicillin-proton pump inhibitor dual therapy, and to provide a new eradication regimen as a first-line option for patients with H. pylori infection.

METHODS

A total of 971 H. pylori positive patients who received initial treatment were recruited from March to August 2020, and randomly divided into treatment group and control group. The treatment group received of 20 mg esomeprazole four times daily and 750 mg amoxicillin four times daily for 14 days. Control group received of 220 mg bismuth potassium citrate twice daily, 20 mg esomeprazole twice daily, 1000 mg amoxicillin twice daily and 250 mg clarithromycin capsule twice daily for 14 days. Four weeks after the end of treatment, the urea breath test was reviewed to detect whether H. pylori was eradicated.

RESULTS

There were no statistical differences in age, gender, the total clinical symptom scores before and after initial treatment, the compliance, and the degree of remission of symptoms before and after initial treatment between the two groups. The eradication rates of H. pylori between dual therapy and quadruple therapy were 88.31% and 85.26% (p=.158) by intention-to-treat (ITT) analysis, 88.66% and 85.44% (p=.186) by modified intention-to-treat (mITT) analysis, and 91.63% and 90.60% (p=.116) by PP analysis, respectively. Adverse events in dual therapy group were significantly lower than quadruple therapy group (13.3% vs. 28.2% (p<.01)).

CONCLUSIONS

For the initial treatment of H. pylori infection, the high-dose dual therapy regimen has the same efficacy as the bismuth-containing quadruple therapy regimen, good compliance, less adverse reactions and high safety, so it can be recommended as the empirical first-line treatment regimen for the eradication of H. pylori (KY2019173).

Gestational Antibodies to C. pneumoniae, H. pylori and CMV in Women with Preeclampsia and in Matched Controls

OBJECTIVES

Some research has suggested a possible role for past infection in the development of preeclampsia. The objective of this study was to explore the role of Helicobacter pylori, cytomegalovirus, and Chlamydophila pneumoniae in the development of preeclampsia in a prospective pregnancy sample.

METHODS

We conducted a nested case-control study in The Archive for Child Health (ARCH), a pregnancy cohort of 867 unselected women enrolled at the first prenatal visit with archived blood and urine in pregnancy. We matched 21 cases of preeclampsia to 52 unaffected controls on maternal age (±4 years), race, parity, and gestational age at blood draw. Using conditional logistic regression, we examined the association between preeclampsia status and immunoglobulins G (IgG) tested by indirect ELISA to each of the three microorganisms, adjusting for potential confounders.

RESULTS

No significant difference was found between cases and controls. The unadjusted odds ratio was 1.5 (95%CI: 0.2-9.1), 0.6 (95%CI: 0.2-1.9), and 1.9 (95%CI: 0.6-5.6) for H. pylori, cytomegalovirus and C. pneumoniae respectively. After controlling for confounders analysis found increased odds of H. pylori IgG (AOR: 1.9; 95% CI: 0.2-15.3) and C. pneumoniae IgG (AOR: 2.3; 95% CI: 0.6-9.2) for preeclampsia, albeit being not significant. Conversely, cytomegalovirus IgG had lower odds for preeclampsia (AOR: 0.4; 95% CI: 0.1-1.7).

CONCLUSIONS

Past infection with H. pylori, and C. pneumoniae in early pregnancy showed a higher risk of preeclampsia, but the findings failed to achieve statistical significance. Cytomegalovirus was not associated with preeclampsia in these data. These preliminary findings encourage future research in populations with high prevalence of these infections.

Magnitude of H. pylori and Its Association with Preeclampsia Among Pregnant Women in Ethiopia: A Case Control Study

Background

Helicobacter pylori infections are associated with many complications of pregnancy including preeclampsia. It has been suggested that H. pylori infection could contribute to the etiopathogenesis of preeclampsia by inducing a pro-inflammatory state.

Objective

To assess the magnitude of H. pylori infection and its association with preeclamptic and non-preeclamptic pregnant women attending antenatal care in Ethiopia.

Methods

Hospital-based case control study was conducted among clinically diagnosed preeclamptic and non-preeclamptic pregnant women. Stool samples were collected for H. pylori antigen test from study participants. The collected data were analyzed using statistical methods in SPSS version 23. Simple descriptive statistics were used to present the socio-demographic and clinical characteristics of the study subjects. Association between clinical variables, preeclampsia and H. pylori infection was performed with multivariate logistic regression. A p-value of <0.05 at 95% confidence level was considered as statistically significant in all the analyses.

Results

A total of 93 cases and 186 controls were included in this study. The overall prevalence of H. pylori infection in all study participants was 38.9% (16/272). The prevalence of H. pylori infection was higher in cases than controls, 54.3% (50/92) vs 31.1% (56/180), respectively. The mean age was 29.01 (SD±4.93) years in cases and 30.37 (SD± 6.2) years in control group. A positive association was found between H. pylori infection and preeclampsia (OR: 2.45; 95% CI: 2.41–4.10).

Conclusion

H. pylori infection has been found to be associated with preeclamptic pregnant women. In this study, the prevalence of H. pylori infection was higher in cases than in controls. Age group, educational status, occupational status and body mass index were significantly associated with preeclamptic women with H. pylori. The association of H. pylori with preeclampsia needs to be further explored.

Bone Fragility in Gastrointestinal Disorders

Osteoporosis is a common systemic disease of the skeleton, characterized by compromised bone mass and strength, consequently leading to an increased risk of fragility fractures. In women, the disease mainly occurs due to the menopausal fall in estrogen levels, leading to an imbalance between bone resorption and bone formation and, consequently, to bone loss and bone fragility. Moreover, osteoporosis may affect men and may occur as a sequela to different diseases or even to their treatments. Despite their wide prevalence in the general population, the skeletal implications of many gastrointestinal diseases have been poorly investigated and their potential contribution to bone fragility is often underestimated in clinical practice. However, proper functioning of the gastrointestinal system appears essential for the skeleton, allowing correct absorption of calcium, vitamins, or other nutrients relevant to bone, preserving the gastrointestinal barrier function, and maintaining an optimal endocrine-metabolic balance, so that it is very likely that most chronic diseases of the gastrointestinal tract, and even gastrointestinal dysbiosis, may have profound implications for bone health. In this manuscript, we provide an updated and critical revision of the role of major gastrointestinal disorders in the pathogenesis of osteoporosis and fragility fractures.

Association between helicobacter pylori infection and subclinical atherosclerosis: A systematic review and meta-analysis

BACKGROUND

The relationship between Helicobacter pylori (H. pylori) infection and subclinical atherosclerosis has been confirmed, but these conclusions are still controversial. Therefore, we have performed a systematic review and meta-analysis to assess the association between H. pylori infection and subclinical atherosclerosis.

METHODS

Databases including PubMed, Embase, Web of Science were searched for the articles on the association of carotid intima-media thickness or pulse wave velocity with H. pylori infection published up to January 1, 2020. Stata 12.0 was used to calculate standardized mean difference (SMD) and 95% confidence interval (95% CI); the I2 test was used to evaluate heterogeneity between studies and sensitivity analysis and subgroup analysis were used to explore the source of heterogeneity. Funnel plot, Begg test, and Egger test were used to estimate publication bias.

RESULTS

Data were extracted from 18 studies involving 6776 subjects with H. pylori positive and 7794 with H. pylori negative. H. pylori positive subjects is significantly associated with increased subclinical atherosclerosis as determined by carotid intima-media thickness (SMD: 0.376 mm; 95% CI: 0.178, 0.574; P < .001, I2 = 90.6%), pulse wave velocity (SMD: 0.320 m/s; 95% CI: 0.242, 0.398; P < .001, I2 = 52.6%), compared with H. pylori negative. Similar results were observed when subgroups analysis were stratified according to age, male ratio, geographical location, H. pylori diagnosis, and study design. Sensitivity analyses showed that our results were robust. The Begg test or Egger test showed no significant publication bias (all P > .05).

CONCLUSIONS

This meta-analysis confirmed a significant association between H. pylori and subclinical atherosclerosis, which will help H. pylori patients to establish effective strategies for the prevention and control of cardiovascular events.

Helicobacter pylori Infection and Extragastric Diseases-A Focus on the Central Nervous System

Helicobacter pylori (H. pylori) is most known to cause a wide spectrum of gastrointestinal impairments; however, an increasing number of studies indicates that H. pylori infection might be involved in numerous extragastric diseases such as neurological, dermatological, hematologic, ocular, cardiovascular, metabolic, hepatobiliary, or even allergic diseases. In this review, we focused on the nervous system and aimed to summarize the findings regarding H. pylori infection and its involvement in the induction/progression of neurological disorders. Neurological impairments induced by H. pylori infection are primarily due to impairments in the gut-brain axis (GBA) and to an altered gut microbiota facilitated by H. pylori colonization. Currently, regarding a potential relationship between Helicobacter infection and neurological disorders, most of the studies are mainly focused on H. pylori.

Three-Decade Failure to the Eradication of Refractory Helicobacter pylori Infection and Recent Efforts to Eradicate the Infection

BACKGROUND

Helicobacter pylori causes dangerous and deadly diseases such as gastric cancer and duodenal ulcers. Eradication and treatment of this bacterium are very important due to the deadly diseases caused by H. pylori and the high cost of treatment for countries.

METHODS

Thus, we present a complete list of the most important causes of failure in the treatment and eradication of H. pylori, and address new therapeutic methods that may be effective in controlling this bacterium in the future.

RESULTS

Many efforts have been made to control and eradicate this bacterium over the years, but no success has been achieved since its eradication is a complex process affected by the bacterial properties and host factors. Previous studies have shown that various factors are involved in the failure to eradicate H. pylori, such as new genotypes of the bacterium with higher pathogenicity, inappropriate patient cooperation, mutations, biofilm formation and dormant forms that cause antibiotic resistance, acidic stomach pH, high bacterial load, smoking, immunosuppressive features and intracellular occurrence of H. pylori. On the other hand, recent studies reported that the use of probiotics, nanoparticles, antimicrobial peptides, natural product and vaccines can be helpful in the treatment and eradication of H. pylori infections.

CONCLUSION

Eradication of H. pylori is crucial for the treatment of important diseases such as gastric cancer. Therefore, it seems that identifying the failure causes of treating this bacterium can be helpful in controlling the infections. Besides, further studies on new therapeutic strategies may help eradicate H. pylori in the future.

3-Pentylcatechol, a Non-Allergenic Urushiol Derivative, Displays Anti-Helicobacter pylori Activity In Vivo

We previously reported that 3-pentylcatechol (PC), a synthetic non-allergenic urushiol derivative, inhibited the growth of Helicobacter pylori in an in vitro assay using nutrient agar and broth. In this study, we aimed to investigate the in vivo antimicrobial activity of PC against H. pylori growing in the stomach mucous membrane. Four-week-old male C57BL/6 mice (n = 4) were orally inoculated with H. pylori Sydney Strain-1 (SS-1) for 8 weeks. Thereafter, the mice received PC (1, 5, and 15 mg/kg) and triple therapy (omeprazole, 0.7 mg/kg; metronidazole, 16.7 mg/kg; clarithromycin, 16.7 mg/kg, reference groups) once daily for 10 days. Infiltration of inflammatory cells in gastric tissue was greater in the H. pylori-infected group compared with the control group and lower in both the triple therapy- and PC-treated groups. In addition, upregulation of cytokine mRNA was reversed after infection, upon administration of triple therapy and PC. Interestingly, PC was more effective than triple therapy at all doses, even at 1/15th the dose of triple therapy. In addition, PC demonstrated synergism with triple therapy, even at low concentrations. The results suggest that PC may be more effective against H. pylori than established antibiotics.

Helicobacter pylori Related Diseases and Osteoporotic Fractures (Narrative Review)

Osteoporosis (OP) and osteoporotic fractures (OFs) are common multifactorial and heterogenic disorders of increasing incidence. Helicobacter pylori (H.p.) colonizes the stomach approximately in half of the world's population, causes gastroduodenal diseases and is prevalent in numerous extra-digestive diseases known to be associated with OP/OF. The studies regarding relationship between H.p. infection (HPI) and OP/OFs are inconsistent. The current review summarizes the relevant literature on the potential role of HPI in OP, falls and OFs and highlights the reasons for controversies in the publications. In the first section, after a brief overview of HPI biological features, we analyze the studies evaluating the association of HPI and bone status. The second part includes data on the prevalence of OP/OFs in HPI-induced gastroduodenal diseases (peptic ulcer, chronic/atrophic gastritis and cancer) and the effects of acid-suppressive drugs. In the next section, we discuss the possible contribution of HPI-associated extra-digestive diseases and medications to OP/OF, focusing on conditions affecting both bone homeostasis and predisposing to falls. In the last section, we describe clinical implications of accumulated data on HPI as a co-factor of OP/OF and present a feasible five-step algorithm for OP/OF risk assessment and management in regard to HPI, emphasizing the importance of an integrative (but differentiated) holistic approach. Increased awareness about the consequences of HPI linked to OP/OF can aid early detection and management. Further research on the HPI-OP/OF relationship is needed to close current knowledge gaps and improve clinical management of both OP/OF and HPI-related disorders.

Reconsidering the "protective" hypothesis of Helicobacter pylori infection in eosinophilic esophagitis

Since its discovery, Helicobacter pylori (H. pylori) has attracted attention in the biomedical world with its numerous pathophysiologic implications, both gastrointestinal and systemic. Beyond its well-established carcinogenic properties, emerging evidence also supports "harmful" proinflammatory and neurodegenerative roles of H. pylori. On the other hand, H. pylori infection has been proposed to be "protective" against several diseases, such as asthma and gastroesophageal reflux disease. Eosinophilic esophagitis (EoE) is a relatively new, allergen/immune-mediated disease, which has also been linked to these considerations. Main arguments are a postulated shift of immune responses by H. pylori from T helper 2 (T_H 2) to T_H 1 polarization, as well as a potential decline of the H. pylori burden with the dramatic parallel rise of ΕοΕ: a series of observational studies reported an inverse association. In this review, we counter these arguments by providing further epidemiological data, which point out that this generalization might be rather incomplete. We also discuss the limitations of the existing studies evaluating a possible association. Furthermore, we provide current evidence on common pathogenetic components, which share both entities. In summary, the claim that H. pylori is protective against EoE is rather incomplete, and further mechanistic studies are necessary to elucidate a possible association.

Association between Active Helicobacter pylori Infection and Glaucoma: A Systematic Review and Meta-Analysis

Background: Glaucoma is the second most common cause of blindness worldwide affecting almost 70 million individuals. Helicobacter pylori (H. pylori) is a widespread pathogen with systematic pathogenicity. This meta-analysis aimed to estimate the contradictory data regarding a potential association between active H. pylori infection and glaucoma. Materials and Methods: A research in MEDLINE/PubMed and Google Scholar was conducted and original studies investigating the relationship between H. pylori infection and glaucoma were included. Analysis was performed with random effects model. The main outcome was the odds ratio (OR) with 95% confidence intervals (CI) of H. pylori infection as a risk factor for glaucoma. A parallel analysis studied the role of active infection as indicated by histology and the titer of anti-H. pylori antibodies. For the anti-H. pylori antibody titers, weighted mean differences (WMD) were estimated between patients and controls. Results: Fifteen studies were included, with 2664 participants (872 patients with glaucoma and 1792 controls), divided into primary open-angle glaucoma (POAG), normal tension glaucoma (NTG) and pseudo-exfoliation glaucoma (PEG). The association between H. pylori infection and overall glaucoma was significant (OR = 2.08, CI 95% 1.48–2.93) with moderate heterogeneity (I² = 61.54%). After stratification by glaucoma subtype, heterogeneity was eliminated in the NTG subgroup. Studies with healthy controls, and controls with anemia yielded very low or no heterogeneity, respectively. Gastric biopsy to document active H. pylori infection yielded the highest OR (5.4, CI: 3.17–9.2, p < 0.001) and null heterogeneity. For anti-H. pylori antibody titers, there was a significant difference in WMD between patients and controls (WMD 15.98 IU/mL; 95% CI: 4.09–27.87; p = 0.008); values were greater in glaucoma patients, with high heterogeneity (I²: 93.8%). Meta-regression analysis showed that mean age had a significant impact on glaucoma (p = 0.037). Conclusions: Active H. pylori infection may be associated with glaucoma with null heterogeneity, as, beyond histology, quantified by anti-H. pylori titers and increases with age.

Association between Helicobacter pylori infection and kidney damage in patients with peptic ulcer

Background:Helicobacter pylori (H. pylori) is relevant to several renal diseases. Our previous research indicates that cytotoxin-associated gene A (CagA) of H. pylori increases secretion of serum immunoglobulin A1 (IgA1) and induces the underglycosylation of IgA1, one of the key factors causing IgA nephropathy. Here, we aimed to study the correlation between H. pylori infection and kidney damage in patients with peptic ulcer, and evaluate the effect of H. pylori eradication on kidney damage.

Methods:¹⁴C-urea breath test and rapid urease tests were applied to H. pylori infection detection. Random urine samples are subjected to the albumin–creatinine ratio (ACR) examination. The correlation between ACR and H. pylori infection was analyzed in patients with peptic ulcer and healthy controls. The levels of IgA and underglycosylated IgA1 in serum are also detected by enzyme-linked immunosorbent assay (ELISA) and Helix aspersa lectin (HAA) binding assay.

Results: (1) H. pylori infection rate in patients with peptic ulcer (88.14%) is significantly higher than that in healthy controls (42.68%). (2) There is a positive correlation between H. pylori infection and ACR abnormal in patients with peptic ulcer (p = .025), while showing a negative correlation in healthy individuals (p = .571). (3) Urinary ACR was uncorrelated with the severity of H. pylori infection in the 27 abnormal urinary ACR cases of the patients with peptic ulcer. (4) After H. pylori eradication, the ACR rates of H. pylori-positive patients with peptic ulcer were significantly decreased (p<.01).

Conclusions: (1) For the H. pylori-positive patients with peptic ulcer, H. pylori infection may be a risk factor resulting in kidney damage. (2) H. pylori eradication probably benefits to kidney damage relief and chronic kidney disease prevention.

Eradication of Helicobacter pylori: the power of nanosized formulations

Helicobacter pylori is a pathogen that is considered to cause several gastric disorders such as chronic gastritis, peptic ulcer and even gastric carcinoma. The current therapeutic regimens mainly constitute of a combination of several antimicrobial agents and proton pump inhibitors. However, the prevalence of antibiotic resistance has been significantly lowering the cure rates over the years. Nanocarriers possess unique strengths in this regard owing to the fact that they can protect the drugs (such as antibiotics) from the harsh environment in the stomach, penetrate the mucosal barrier and deliver drugs to the desired site. In this review we summarized recent studies of different antibacterial agents orally delivered by nanosized carriers for the eradication of H. pylori.

Association between Helicobacter pylori infection and arterial stiffness: Results from a large cross-sectional study

Background

Chronic systemic inflammation is an important causative factor in the pathogenesis of atherosclerosis. However, the effect of chronic Helicobacter pylori (Hp) infection on arterial stiffness, a predictor of cardiovascular events, remains unclear. We evaluated the association between Hp infection and arterial stiffness in asymptomatic healthy individuals.

Methods

Arterial stiffness was evaluated using the cardio-ankle vascular index (CAVI). We included subjects who underwent CAVI and anti-Hp IgG antibody evaluations, simultaneously, between March 2013 and July 2017. Demographic characteristics and metabolic and cardiovascular parameters were compared with respect to anti-Hp IgG antibody status. Multivariable logistic regression analyses were performed to determine the effect of Hp-seropositivity and conventional cardiovascular risk factors on arterial stiffness.

Results

Of 2,251 subjects, 1,326 (58.9%) were included in the Hp-seropositive group. Median age (P < 0.001) and systolic blood pressure (P = 0.027) were significantly higher in the Hp-seropositive than in the Hp-seronegative group. Levels of LDL-cholesterol were significantly higher in the Hp-seropositive than in the Hp-seronegative group (P = 0.016). Other serum metabolic parameters were not significantly different between the two groups. The median CAVI value and the proportion of subjects with a CAVI ≥ 8 were significantly higher in the Hp-seropositive than in the Hp-seronegative group (both P < 0.001). On multivariable logistic regression analyses, Hp-seropositivity, age, body mass index, waist circumference, smoking, hypertension, diabetes mellitus, and dyslipidemia were significantly associated with high CAVI values. In the subgroup analysis conducted according to age group, a tendency towards an increased association between Hp-seropositivity and CAVI was observed with increasing age, even though the difference did not reach the statistical significance.

Conclusions

Hp-seropositivity was significantly associated with arterial stiffness. Hp infection may contribute to the development of cardiovascular diseases.

Helicobacter pylori Vacuolating Cytotoxin A Causes Anorexia and Anxiety via Hypothalamic Urocortin 1 in Mice

Helicobacter pylori (Hp) infection is related to the pathogenesis of chronic gastric disorders and extragastric diseases. Here, we examined the anorexigenic and anxiogenic effects of Hp vacuolating cytotoxin A (VacA) through activation of hypothalamic urocortin1 (Ucn1). VacA was detected in the hypothalamus after peripheral administration and increased Ucn1 mRNA expression and c-Fos-positive cells in the hypothalamus but not in the nucleus tractus solitarius. c-Fos and Ucn1-double positive cells were detected. CRF1 and CRF2 receptor antagonists suppressed VacA-induced anxiety and anorexia, respectively. VacA activated single paraventricular nucleus neurons and A7r5 cells; this activation was inhibited by phospholipase C (PLC) and protein kinase C (PKC) inhibitors. VacA causes anorexia and anxiety through the intracellular PLC-PKC pathway, migrates across the blood-brain barrier, and activates the Ucn1-CRF receptor axis.

H. pylori infection and extra-gastroduodenal diseases

Helicobacter pylori infection is the principal cause of peptic ulcer disease, gastric adenocarcinoma and gastric mucosa-associated lymphoid tissue lymphoma. Recent studies have shown that it may interfere with many biological processes and determine or influence the occurrence of many diseases outside the stomach. Currently, the role of H. pylori in idiopathic thrombocytopenic purpura and iron deficiency anemia is well documented. Emerging evidence suggests that it may also contribute to vitamin B12 deficiency, insulin resistance, metabolic syndrome, diabetes mellitus and non-alcoholic liver disease. Additionally, it may increase the risk of acute coronary syndrome, cerebrovascular disease, neurodegenerative disease and other miscellaneous disorders. Different pathogenic mechanisms have been hypothesized, including the occurrence of molecular mimicry and the induction of a low-grade inflammation. This review summarizes the results of the most relevant studies on the extra-gastroduodenal manifestations of H. pylori infection.

Polymorphisms in the Helicobacter pylori NY43 strain and its prophage-cured derivatives

This study aimed to determine the characteristics of the Helicobacter pylori host NY43 strain and its prophage-cured derivative. H. pylori colonizing the human stomach cause many diseases. They show high genetic diversity, allowing the development of mutant strains that can form bacterial communities adapted to specific environmental conditions. Bacteriophage activities are associated with bacterial evolution, including pathogenicity development. Herein, we reported the complete genome sequence and genomic organization of two H. pylori prophages, KHP30 and KHP40; the effects of KHP30 on the behaviours of NY43 are not yet known. We showed that approximately 57 % prophage-cured derivatives spontaneously appeared in the exponential phase during liquid culture, and the biological characteristics of these derivatives differed from those of the host NY43. KHP30 reinfected the cured derivatives, and the curing ratio was influenced by culture conditions. KHP30 was shown to promote the development of a flexible H. pylori community with variable characteristics.

Furazolidone treatment for Helicobacter Pylori infection: A systematic review and meta-analysis

Antibiotic resistance is a major cause of Helicobacter pylori (H. pylori) treatment failures. Because the resistance rate of H. pylori to furazolidone is low, we aimed to assess the efficacy and safety of furazolidone. We searched the PubMed, Web of Science, Cochrane Library, and Embase databases and included randomized controlled trials (RCT) that either compared furazolidone to other antibiotics or changed the administered dose of furazolidone. A total of 18 articles were included in the meta-analysis. According to the intention-to-treat (ITT) analysis, the total eradication rates of furazolidone-containing therapy were superior to those of other antibiotic-containing therapies (relative risk [RR] 1.07, 95% confidence interval [CI] 1.01-1.14) (13 RCTs). Specifically, the eradication rates of furazolidone-containing therapy were better than those for metronidazole-containing therapy (RR 1.10, 95% CI: 1.01-1.21 for ITT). The eradication rate of furazolidone-containing bismuth-containing quadruple therapy was 92.9% (95% CI: 90.7%-95.1%) (PP). In addition, a higher daily dose of furazolidone increased the eradication rate (RR 1.17, 95% CI: 1.05-1.31). And the incidence of some adverse effects, such as fever and anorexia, was higher in the furazolidone group than in the control group, the overall incidences of total side effects and severe side effects showed no significant differences between the groups. Furazolidone-containing treatments could achieve satisfactory eradication rates and did not increase the incidence of total or severe adverse effects, but the incidence of milder side effects, such as fever and anorexia, should be considered when prescribing furazolidone-containing treatments to patients.

Fifth Chinese National Consensus Report on the management of Helicobacter pylori infection

BACKGROUND

Since the 'Fourth Chinese National Consensus Report on the management of H. pylori infection' was published in 2012, three important consensuses (Kyoto global consensus report on H. pylori gastritis, The Toronto Consensus for the Treatment of H. pylori Infection in Adults and Management of H. pylori infection-the Maastricht V/Florence Consensus Report) have been published regarding the management of H. pylori infection.

MATERIALS AND METHODS

A Delphi method was adopted to develop the consensus of relevant 'statements'. First, the established 'statements' were sent to experts via email. Second, after undergoing two rounds of consultation, the initial statements were discussed face to face and revised in the conference item by item on 16 December 2016. Finally, 21 core members of conferees participated in the final vote of statements. Voting for each statement was performed using an electronic system with levels of agreements shown on the screen in real time.

RESULTS

Consensus contents contained a total of 48 "statements" and related 6 parts, including indications for H. pylori eradication, diagnosis, treatment, H. pylori and gastric cancer, H. pylori infection in special populations, H. pylori and gastrointestinal microbiota.

CONCLUSIONS

Recommendations are provided on the basis of the best available evidence.

Review: Impact of Helicobacter pylori on Alzheimer's disease: What do we know so far?

BACKGROUND

Helicobacter pylori has changed radically gastroenterologic world, offering a new concept in patients' management. Over time, more medical data gave rise to diverse distant, extragastric manifestations and interactions of the "new" discovered bacterium. Special interest appeared within the field of neurodegenerative diseases and particularly Alzheimer's disease, as the latter and Helicobacter pylori infection are associated with a large public health burden and Alzheimer's disease ranks as the leading cause of disability. However, the relationship between Helicobacter pylori infection and Alzheimer's disease remains uncertain.

METHODS

We performed a narrative review regarding a possible connection between Helicobacter pylori and Alzheimer's disease. All accessible relevant (pre)clinical studies written in English were included. Both affected pathologies were briefly analyzed, and relevant studies are discussed, trying to focus on the possible pathogenetic role of this bacterium in Alzheimer's disease.

RESULTS

Data stemming from both epidemiologic studies and animal experiments seem to be rather encouraging, tending to confirm the hypothesis that Helicobacter pylori infection might influence the course of Alzheimer's disease pleiotropically. Possible main mechanisms may include the bacterium's access to the brain via the oral-nasal-olfactory pathway or by circulating monocytes (infected with Helicobacter pylori due to defective autophagy) through disrupted blood-brain barrier, thereby possibly triggering neurodegeneration.

CONCLUSIONS

Current data suggest that Helicobacter pylori infection might influence the pathophysiology of Alzheimer's disease. However, further large-scale randomized controlled trials are mandatory to clarify a possible favorable effect of Helicobacter pylori eradication on Alzheimer's disease pathophysiology, before the recommendation of short-term and cost-effective therapeutic regimens against Helicobacter pylori-related Alzheimer's disease.

Choroidal Thickness of Helicobacter-Positive Patients without Central Serous Chorioretinopathy

PURPOSE

To evaluate the effect of Helicobacter pylori (H. pylori) infection on subfoveal choroidal thickness (SFCT) in patients without clinical central serous chorioretinopathy (CSC).

MATERIALS AND METHODS

This prospective study included 50 patients with pathologically proven H. pylori infection (H. pylori (+)) and 50 patients without H. pylori infection (H. pylori (-)). All of the recruited patients were previously admitted to the Gastroenterology Department of the Namik Kemal University School of Medicine over the period of July 2014 to September 2015. All patients had 20/20 vision and underwent complete ophthalmological examination, macular optical coherence tomography (OCT), and enhanced depth imaging OCT.

RESULTS

All patients had 20/20 vision and similar macular thicknesses. The mean SFCT of patients in the H. pylori (+) group was 309 ± 41.1 µm and 315 ± 18.2 µm in the H. pylori (-) group (p = 0.174). The right and left eyes of patients in the H. pylori (+) and (-) groups were not statistically significantly different (p = 0.852, p = 0.937). The age, sex, and choroidal thicknesses of patients in the H. pylori (+) and (-) groups were not correlated.

CONCLUSION

H. pylori infection does not have an effect on choroidal thickness in patients without any ocular pathology.

Antibiotic resistance of Helicobacter pylori to 16 antibiotics in clinical patients

BACKGROUND

Resistance of Helicobacter pylori (H. pylori) to antibiotics is increasing worldwide. To determine the status of H. pylori resistance and its patterns in clinical patients, an investigation utilizing susceptibility testing for commonly used antibiotics was needed.

METHODS

Total of 2283 H. pylori strains were collected from 2013 to 2016. The resistance and its patterns of these strains were tested by agar dilution method. The resistance rate and minimal inhibition concentration (MIC) in different gender groups were also analyzed.

RESULTS

The overall resistance rates were as following: amoxicillin (1.58%), clarithromycin (22.73%), levofloxacin (24.75%), furazolidone (1.49%), doxycycline (9.20%), cefetamet (97.20%), ceftriaxone (49.60%), cefuroxime (25.20%), gentamicin (3.73%), azithromycin (85.60%), rifampicin (2.80%), metronidazole (92.53%), ornidazole (94.27%), tinidazole (87.20%), ciprofloxacin (43.20%), and moxifloxacin (38.53%). There were only 64.08% strains pan-susceptible to amoxicillin, clarithromycin, levofloxacin, and furazolidone, followed by mono resistance (23.17%), double resistance (11.13%), triple resistance (1.36%), and quadruple resistance (0.26%). Significant differences in the resistance rate and MIC were also observed in different gender groups.

CONCLUSION

Antibiotic resistance trends of H. pylori is increasing in clinical patients. With the increasing resistance, it is imperative to individualized therapy based on the results of drug susceptibility testing.

Relationship of Helicobacter pylori seroprevalence with the occurrence and severity of psoriasis

BACKGROUND

Psoriasis is a chronic inflammatory disease that affects the skin and joints and has a multifactorial etiology. Recently, it has been suggested that Helicobacter pylori infection may contribute as a trigger for the development of the disease.

OBJECTIVES

To determine the prevalence of H. pylori seropositivity in patients with psoriasis and to evaluate the relation between disease severity and H. pylori infection.

METHODS

H. pylori infection was assessed in psoriatic patients and controls by using H. pylori IgG quantitative enzyme immunoassay (ELISA test). The patients were classified according to the severity of the disease (PASI score).

RESULTS

One hundred and twenty six patients with psoriasis (73 females and 53 males); mean age 50.48 years; 65 patients (51.59%) had severe psoriasis, 40 (31.75%) moderate psoriasis and 21 (16.67%) mild psoriasis. Twenty one healthy volunteers included as a control group, mean age of 41.05 years, 13 females and 8 males. One hundred and eleven patients with psoriasis tested serologically, 80 (72.07%) were seropositive compared with 7 positive volunteers (33.33%; P=0.002). Forty-nine (75.38%) patients with severe psoriasis were positive, 25 (62.50%) with moderate psoriasis were positive and 6 (28.57%) with mild psoriasis were positive (P=0.045). Study limitations: none.

CONCLUSIONS

H. pylori infection influences the development of psoriasis and severity of the disease.

Helicobacter pylori infection, atrophic gastritis, and pancreatic cancer risk: A meta-analysis of prospective epidemiologic studies

BACKGROUND

To investigate the associations of Helicobacter pylori (Hp) infection and atrophic gastritis (AG) with pancreatic cancer risk.

METHODS

A literature search in PubMed was performed up to July 2017. Only prospective cohort and nested case-control studies enrolling cancer-free participants were eligible. Incident pancreatic cancer cases were ascertained during the follow-up. The risks of pancreatic cancer were compared between persons infected and noninfected with Hp, or between those with and without AG status at baseline. Odds ratios (ORs) or hazard ratios were combined. Subgroup and sensitivity analyses were performed, and publication bias was estimated.

RESULTS

Three cohort studies and 6 nested case-control studies, including 65,155 observations, were analyzed. The meta-analyses did not confirm the association between pancreatic cancer risk and Hp infection (OR = 1.09, 95% confidence interval [CI] = 0.81-1.47) or AG status (OR = 1.18, 95% CI = 0.80-1.72). However, particular subpopulations potentially had increased risks of pancreatic cancer. Cytotoxin-associated gene A (CagA)-negative strains of Hp might be a causative factor of pancreatic cancer (OR = 1.30, 95% CI = 1.05-1.62), but a sensitivity analysis by leave-one-out method did not fully warrant it (OR = 1.20, 95% CI = 0.93-1.56). In 1 nested case-control study, AG at stomach corpus in Hp-negative subpopulation might have increased risk of pancreatic cancer, but with a poor test power = 0.56. Publication biases were nonsignificant in the present meta-analysis.

CONCLUSION

Based on current prospective epidemiologic studies, the linkage of pancreatic cancer to Hp infection or AG status was not warranted on the whole. Nevertheless, prospective studies only focusing on those specific subpopulations are further required to obtain better power.

Helicobacter Pylori Infection in Texas Hispanic and Non-Hispanic White Men: Implications for Gastric Cancer Risk Disparities

Chronic Helicobacter pylori ( H. pylori) infection is a major gastric adenocarcinoma (GA) risk factor. GA disproportionately affects U.S. Hispanics compared with non-Hispanic Whites (NHWs). Since H. pylori infection studies in Hispanics are few, infection rates in Hispanic and NHW men in Bexar County were compared, and relationships with ethnicity and obesity examined. Age- and zip code-matched participants from a community-dwelling cohort were randomly selected. Sera from 284 men were analyzed by enzyme immunoassay for H. pylori antibodies. Adjusted risk ratio estimation for matched data was conducted to identify differences. Hispanics had a markedly higher prevalence of infection (30.3%) than NHWs (9.2%). Matched risk ratio (mRR) analyses revealed a strong association between H. pylori seropositivity and Hispanic ethnicity (mRR = 3.31; 95% CI [1.91, 5.73], adjusted by BMI, smoking status, and family history of cancer (mRR range = 3.28-3.89). BMI mRRs (range = 1.19-1.22) were significant in all models. In this cohort, Hispanic men had higher H. pylori infection rates than NHWs, and parallel the disproportionately higher rates of GA; obesity contributes to this higher prevalence. Future studies should address country of origin, acculturation, and other factors influencing obesity to further elucidate risk of GA in Hispanic populations.

Enterosalivary nitrate metabolism and the microbiome: Intersection of microbial metabolism, nitric oxide and diet in cardiac and pulmonary vascular health

Recent insights into the bioactivation and signaling actions of inorganic, dietary nitrate and nitrite now suggest a critical role for the microbiome in the development of cardiac and pulmonary vascular diseases. Once thought to be the inert, end-products of endothelial-derived nitric oxide (NO) heme-oxidation, nitrate and nitrite are now considered major sources of exogenous NO that exhibit enhanced vasoactive signaling activity under conditions of hypoxia and stress. The bioavailability of nitrate and nitrite depend on the enzymatic reduction of nitrate to nitrite by a unique set of bacterial nitrate reductase enzymes possessed by specific bacterial populations in the mammalian mouth and gut. The pathogenesis of pulmonary hypertension (PH), obesity, hypertension and CVD are linked to defects in NO signaling, suggesting a role for commensal oral bacteria to shape the development of PH through the formation of nitrite, NO and other bioactive nitrogen oxides. Oral supplementation with inorganic nitrate or nitrate-containing foods exert pleiotropic, beneficial vascular effects in the setting of inflammation, endothelial dysfunction, ischemia-reperfusion injury and in pre-clinical models of PH, while traditional high-nitrate dietary patterns are associated with beneficial outcomes in hypertension, obesity and CVD. These observations highlight the potential of the microbiome in the development of novel nitrate- and nitrite-based therapeutics for PH, CVD and their risk factors.

Helicobacter pylori colonization and pregnancies complicated by preeclampsia, spontaneous prematurity, and small for gestational age birth

BACKGROUND

Preeclampsia (PE), small for gestational age (SGA), and spontaneous preterm birth (PTB) each may be complications of impaired placental function in pregnancy. Although their exact pathogenesis is still unknown, certain infectious agents seem to play a role. Helicobacter pylori (H. pylori) colonization has been associated with increased risk for PE. Our aim was to assess the association between H. pylori colonization and PE, SGA, and PTB.

MATERIAL AND METHODS

We measured IgG anti-H. pylori and CagA antibodies in serum of pregnant women (median 20.5 weeks, range 16.5-29.4) who participated in a population-based prospective cohort study. Delivery and medical records were assessed. Information on demographics, education, and maternal risk factors was collected by questionnaire. We used multivariate logistic regression analyses to assess associations between H. pylori colonization and PE, SGA, and PTB.

RESULTS

In total, 6348 pregnant women were assessed. H. pylori positivity was found in 2915 (46%) women, of whom 1023 (35%) also were CagA-positive. Pregnancy was complicated by PE, SGA, or PTB in 927 (15%) women. H. pylori colonization was associated with PE (aOR 1.51; 95%CI 1.03-2.25). Differentiation according to CagA status revealed the same risk. H. pylori was positively related with SGA, mainly explained by CagA-positive strains (aOR 1.34; 1.04-1.71). No association was observed between H. pylori and PTB.

CONCLUSIONS

Our data suggest that H. pylori colonization may be a risk factor for PE and SGA. If these associations are confirmed by future studies and shown to be causal, H. pylori eradication may reduce related perinatal morbidity and mortality.

Binary mixture of Satureja hortensis and Origanum vulgare subsp. hirtum essential oils: in vivo therapeutic efficiency against Helicobacter pylori infection

BACKGROUND

Helicobacter pylori can cause many gastrointestinal and also extra-gastrointestinal disorders and is a major risk factor for gastric carcinoma and MALT lymphoma. Currently, numerous antibiotic-based therapies are available; however, these therapies have numerous drawbacks, mainly due to increasing prevalence of antibiotic resistant strains. Thus, there is an urgent need to develop novel therapeutic agents against H. pylori infections.

MATERIALS AND METHODS

In this study, the anti-H. pylori activity of 2:1 mixture of Satureja hortensis and Origanum vulgare subsp. hirtum essential oils (2MIX) was investigated in vivo. After screening in vitro cytotoxicity of 2MIX on mammalian cell lines, the therapeutic efficiency was studied in a mouse model, where changes in H. pylori colonization were detected by PCR and histology of gastric samples. The immune reaction of mice was tested based on cytokine and chemokine production, and the in vivo toxicity of 2MIX was also investigated by measuring ALT and AST enzyme activities and Cyp3a11 and HO-1 mRNA levels in livers of mice.

RESULTS

2MIX had not shown in vitro cytotoxicity against cell lines, only the highest concentration caused significant decrease in their survival rates. In the in vivo experiments, 2MIX successfully eradicated the pathogen in 70% of the mice. We could not detect toxicity or altered cytokine and chemokine balance after in vivo treatments in mice.

CONCLUSIONS

These results show that 2MIX is effective in reducing H. pylori colonization suggesting that this essential oil mixture has great potential as a new, effective, and safe therapeutic agent against H. pylori.

Management of Helicobacter pylori infection-the Maastricht V/Florence Consensus Report

Important progress has been made in the management of Helicobacter pylori infection and in this fifth edition of the Maastricht Consensus Report, key aspects related to the clinical role of H. pylori were re-evaluated in 2015. In the Maastricht V/Florence Consensus Conference, 43 experts from 24 countries examined new data related to H. pylori in five subdivided workshops: (1) Indications/Associations, (2) Diagnosis, (3) Treatment, (4) Prevention/Public Health, (5) H. pylori and the Gastric Microbiota. The results of the individual workshops were presented to a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in the various clinical scenarios.

Investigation of a common gene expression signature in gastrointestinal cancers using systems biology approaches

According to GLOBOCAN 2012, the incidence and the mortality rate of colorectal, stomach and liver cancers are the highest among the total gastrointestinal (GI) cancers.

The Role of H. pylori CagA in Regulating Hormones of Functional Dyspepsia Patients

Helicobacter pylori (H. pylori, Hp) colonizes the stomachs of approximately 20%–80% of humans throughout the world. The Word Healthy Organization (WHO) classified H. pylori as a group 1 carcinogenic factor in 1994. Recently, an increasing number of studies has shown an association between H. pylori infection and various extragastric diseases. Functional dyspepsia (FD) is considered a biopsychosocial disorder with multifactorial pathogenesis, and studies have shown that infection with CagA-positive H. pylori strains could explain some of the symptoms of functional dyspepsia. Moreover, CagA-positive H. pylori strains have been shown to affect the secretion of several hormones, including 5-HT, ghrelin, dopamine, and gastrin, and altered levels of these hormones might be the cause of the psychological disorders of functional dyspepsia patients. This review describes the mutual effects of H. pylori and hormones in functional dyspepsia and provides new insight into the pathogenesis of functional dyspepsia.

Increased Exhaled 8-Isoprostane and Interleukin-6 in Patients with Helicobacter pylori Infection

BACKGROUND

Helicobacter pylori (H. pylori) infection triggers both local inflammation, usually in gastric mucosa, and chronic systemic inflammation. It is assumed that this local and systemic inflammation is caused by extracellular products excreted by H. pylori. The aim of this study was to investigate the possible association between H. pylori infection and a local inflammatory response in the airway by using exhaled breath condensate technique.

MATERIALS AND METHODS

This study includes 41 H. pylori seropositive patients who have gastric symptoms and 27 healthy control subjects. Pulmonary function tests (PFT), chest X ray, and physical examination were performed in all patients and interleukin-6 (IL-6), 8-isoprostane and nitrotyrosine levels were measured in exhaled breath condensate.

RESULTS

Levels of IL-6 and 8-isoprostane in exhaled breath condensate (EBC) were significantly higher in H. pylori positive patients than control subjects (p < 0.05). Nitrotyrosine levels were also higher in H. pylori positive patients but the difference was not statistically significant. Both groups had similar leukocyte counts, C-reactive protein (CRP) levels and PFT parameters.

CONCLUSION

H. pylori infection causes an asymptomatic airway inflammation which can be detected by exhaled breath condensate. The clinical importance of this inflammation remains unclear.

Association between Helicobacter pylori seropositivity and mild to moderate COPD: clinical implications in an Asian country with a high prevalence of H. pylori

Background

Helicobacter pylori infection is a major cause of gastric diseases. The clinical implications of H. pylori infection in various diseases outside the gastrointestinal system have also been reported, including in some respiratory disorders. In this study, we investigated the seroprevalence of H. pylori in patients with mild to moderate COPD in an Asian country with a high prevalence of H. pylori infection. Also, we aimed to elucidate the association between the seroprevalence of H. pylori and the decline of lung function in patients with COPD.

Methods

Participants who underwent a medical checkup for H. pylori at a referral hospital in Korea were recruited for this study. All participants were tested for H. pylori infection using an immunoassay of the H. pylori-specific immunoglobulin G (IgG) concentration and a rapid urease test at the time of endoscopy with a gastric mucosal specimen. We assessed the decline in lung function using the spirometric data of those who underwent spirometry more than three times.

Results

In total, 603 participants (201 patients with COPD and 402 controls) were analyzed. The seroprevalence of H. pylori IgG in the patients and controls was 45.8% and 52.2%, respectively (P=0.134). The H. pylori IgG level in patients with COPD was not significantly different from that of the controls (114.8 and 109.6 units/mL, respectively; P=0.549). In addition, there were no significant differences in the annual forced expiratory volume in 1 second or forced vital capacity between the participants with H. pylori seropositivity and seronegativity.

Conclusion

This study showed no relationship between H. pylori infection and COPD in a country with a high burden of H. pylori infection. Furthermore, H. pylori infection did not affect the rate of lung function decline in this study population.

Diet and Helicobacter pylori infection

Helicobacter pylori infection has accompanied man for thousands of years. In some infected patients, a complex and dynamic pathogen-host reaction triggers pathogenic pathways resulting in development, inter alia, of atrophic gastritis, peptic ulcer disease (both gastric and duodenal), gastric adenocarcinoma, and MALT lymphoma. Large-scale eradication therapy is associated with a rapid increase in antibiotic resistance, gut flora composition disturbances, and increased risk of development, inter alia, of paediatric infectious diarrhoeas, atopic diseases, and oesophageal adenocarcinoma. Our diet contains many substances with potent antibacterial activity against H. pylori. Dietary interventions enable a decrease in H. pylori colonisation and result in a decrease in gastritis prevalence, thus potentially lowering the risk of gastric adenocarcinoma development.

Meta-analysis of relationship between Helicobacter pylori infection and type 1 diabetes mellitus

AIM: To investigate the association between Helicobacter pylori (H. pylori) infection and type 1 diabetes mellitus (T1DM).

METHODS: Online databases, including PubMed, Embase, Cochrane Library, Wanfang, VIP and CNKI, were searched for the articles on the association of H. pylori with type 1 diabetes mellitus from the inception of each database to November 2015. Data extraction and quality assessment were completed by two authors. Meta-analysis was performed using RevMan 5.3 software, and the odds ratio and 95% confidence interval (CI) were calculated.

RESULTS: Eleven papers were included for meta-analysis. The total sample size is 2982, with cases and controls being 1085 and 1897, respectively. Compared with the controls, H. pylori infection significantly increased the risk of developing type 1 diabetes mellitus with a pooled OR of 1.68 (95%CI: 1.09-2.59). Results from Meta-regression analyses showed that the distribution of residential areas and detection method being used were not potential influential factors. The results of publication bias and sensitivity analysis confirmed the reliability and stability of this Meta-analysis.

CONCLUSION: H. pylori infection may be associated with an increased risk of developing type 1 diabetes mellitus.

Structural Characteristics of Gastric Cell Populations in Chronic Gastritis and Chronic Hepatitis under Conditions of Helicobacter pylori Persistence

Helicobacter pylori persistence in patients with chronic gastritis is associated with a complex of nonspecific structural reactions, the type of these reactions correlates with the severity of infection: catarrhal fibrotic changes in the gastric mucosa predominate in cases with manifest colonization, while the absence of H. pylori is associated with predominance of fibrotic process. Analysis of the incidence of some pathomorphological phenomena (degeneration, atrophy, metaplasia, and dysplasia of the surface epithelium) shows no relationship between the presence of H. pylori and colonization intensity. In all patients with chronic hepatitis, the gastric mucosa is involved in the pathological process; fibrosis (gastropathy) was the most common process. No appreciable correlations between the structural changes and hepatitis activity and the presence of H. pylori were detected.

A Meta-Analysis of the Association between Helicobacter pylori Infection and Risk of Coronary Heart Disease from Published Prospective Studies

BACKGROUND

The association between helicobacter pylori (Hp) infection and coronary heart disease (CHD) has long been debated, and the results from previous meta-analysis are varied.

AIMS

The aim for this study was to identify the association between Hp and CHD using published perspective cohort studies.

MATERIALS AND METHODS

A systematic review and meta-analysis were performed on studies published from January, 1992 to April, 2014. All studies included used data from prospective cohort studies of CHD events or CHD deaths. Random effect models were applied in all estimations.

RESULTS

H. pylori infection increased the risk of CHD events by 11% (19 studies, n = 22,207, risk ratio (RR) = 1.11, 95% confidence interval (CI): 1.01-1.22). This effect was greater for studies that had less than 5 years' follow-up time (RR = 1.15, 95% CI: 1.00-1.32). However, this effect was not significant for studies that had follow-up times ≥10 years (n = 5100, RR = 1.04, 95% CI: 0.87-1.24). Neither Cag-A seropositive nor Cag-A seronegative strains of H. pylori were associated with a significantly increased risk of CHD events or deaths based on the current published data.

CONCLUSION

In conclusion, H. pylori infection increased the risk of CHD events, especially in a patient's early life, but this association was weaker or might be masked by other CHD risk factors in long-term observations.

Implication of Cytotoxic Helicobacter pylori Infection in Autoimmune Diabetes

Background. Type 1 diabetes (T1D) and type 2 diabetes (T2D) have been linked to Helicobacter pylori infection, although results are conflicting. No previous study addressed a possible link between H. pylori infection and latent autoimmune diabetes in adults (LADA). In this study, a correlation among H. pylori infection and the risk of autoimmune diabetes in comparison with T2D was investigated. Methods. Sera from 234 LADA patients, 105 patients with late-onset T1D, and 156 patients with T2D were analyzed for anti-H. pylori and the cytotoxin-associated antigen (CagA) IgG antibodies. Results. H. pylori seroprevalence was comparable in LADA (52%), late-onset T1D (45%), and T2D (49%) with no gender differences. The seroprevalence of CagA IgG was significantly higher in autoimmune diabetes (late-onset T1D: 45%, LADA: 40%) compared to T2D (25%; p < 0.028). Conclusions. Although H. pylori seroprevalence was similar in LADA, T1D, and T2D, anti-CagA positivity was significantly increased among patients with autoimmune diabetes, suggesting that more virulent H. pylori strains might be a trigger for immune mechanisms involved in their pathogenesis.

A Dormant Microbial Component in the Development of Preeclampsia

Preeclampsia (PE) is a complex, multisystem disorder that remains a leading cause of morbidity and mortality in pregnancy. Four main classes of dysregulation accompany PE and are widely considered to contribute to its severity. These are abnormal trophoblast invasion of the placenta, anti-angiogenic responses, oxidative stress, and inflammation. What is lacking, however, is an explanation of how these themselves are caused. We here develop the unifying idea, and the considerable evidence for it, that the originating cause of PE (and of the four classes of dysregulation) is, in fact, microbial infection, that most such microbes are dormant and hence resist detection by conventional (replication-dependent) microbiology, and that by occasional resuscitation and growth it is they that are responsible for all the observable sequelae, including the continuing, chronic inflammation. In particular, bacterial products such as lipopolysaccharide (LPS), also known as endotoxin, are well known as highly inflammagenic and stimulate an innate (and possibly trained) immune response that exacerbates the inflammation further. The known need of microbes for free iron can explain the iron dysregulation that accompanies PE. We describe the main routes of infection (gut, oral, and urinary tract infection) and the regularly observed presence of microbes in placental and other tissues in PE. Every known proteomic biomarker of "preeclampsia" that we assessed has, in fact, also been shown to be raised in response to infection. An infectious component to PE fulfills the Bradford Hill criteria for ascribing a disease to an environmental cause and suggests a number of treatments, some of which have, in fact, been shown to be successful. PE was classically referred to as endotoxemia or toxemia of pregnancy, and it is ironic that it seems that LPS and other microbial endotoxins really are involved. Overall, the recognition of an infectious component in the etiology of PE mirrors that for ulcers and other diseases that were previously considered to lack one.