Helicobacter pylori infection as a possible risk factor for respiratory system disease: a review of the literature

Aiding gastrointestinal diagnostic laboratory by designing a device for the non invasive detection of peptic ulcer

Peptic ulcer (PU) has been recognized as an utmost gastrointestinal problem that affects the lining of the stomach and duodenum, specifically triggering soreness. It is a life-threatening condition, while roots of the infection are not identified yet. There are various risk factors for the cause of peptic ulcer disease, but the most significant is "Helicobacter pylori" (H. pylori). The detection of this disease involves different invasive procedures which are painful and not feasible for everyone. The aim of this device is to identify the peptic ulcer non-invasively by unmasking the presence of H. Pylori bacterium by monitoring crucial parameters of the disease which include respiration rate, heart rate, ECG, pH of Saliva, and temperature. Multiple investigations related to PU authenticate the alteration in these physicochemical aspects of the body. The increase in the level of stomach acid in PU is responsible for belching and bloating. Heart rate, temperature, and respiratory rate are also elevated during peptic ulcers while the pH of Saliva is decreased toward the acidic side. The disturbance in the QRS complex of the ECG wave is also observed. These biosignals are examined as analog input from the body, sent into MCP3008, and converted into digital input signals. Then these digital inputs are directed toward Raspberry pi 3 which processes, received inputs, and shows output on the LCD. The values of parameters obtained are then compared with standard values and a conclusion is made that whether a patient has a peptic ulcer or not.

The human microbiome: A promising target for lung cancer treatment

Lung cancer is the leading cause of cancer-related deaths worldwide, and insights into its underlying mechanisms as well as potential therapeutic strategies are urgently needed. The microbiome plays an important role in human health, and is also responsible for the initiation and progression of lung cancer through its induction of inflammatory responses and participation in immune regulation, as well as for its role in the generation of metabolic disorders and genotoxicity. Here, the distribution of human microflora along with its biological functions, the relationship between the microbiome and clinical characteristics, and the role of the microbiome in clinical treatment of lung cancer were comprehensively reviewed. This review provides a basis for the current understanding of lung cancer mechanisms with a focus on the microbiome, and contributes to future decisions on treatment management.

Helicobacter pylori Infection Maybe a Risk Factor for Cardiac Syndrome X

Purpose

Cardiac syndrome X (CSX) is a condition with normal coronary angiography but angina pectoris. Chronic inflammation caused by Helicobacter pylori (H. pylori) infection may play a pathogenic role in CSX. Therefore, we conducted a meta-analysis to explore the relationship between H. pylori infection and risk of CSX.

Methods

A systematic search in the Web of Science, Medline, Embase and Chinese databases (CNKI and Wanfang) was conducted up to October 2021. Articles on the association between H. pylori infection and the risk of CSX were included and were analyzed by R software (version 4.1.0).

Results

Ten case-control studies involving 703 CSX patients and 731 healthy controls were included. H. pylori infection was associated with an increased risk of CSX (OR: 8.29, 95% CI: 4.64–14.82). We also found a significant association in those 25–40 years of age (OR: 1.34, 95% CI: 1.04–1.72), those 40–50 years of age (OR: 11.27, 95% CI: 4.29–29.61), those over 50 years of age (OR: 7.18, 95% CI: 3.59–14.36), those in developing countries [Iran (OR: 12.99, 95% CI: 8.61–19.60) and China (OR: 5.14, 95% CI: 3.09–8.56)]. However, this association was not apparent in a developed country [Italy (OR: 0.93, 95% CI: 0.37–2.33)].

Conclusions

Our study suggested a possible association between H. pylori infection and the risk of CSX. Its pathogenicity is stronger in middle-aged individuals and some developing countries. However, more studies are needed to further investigate whether early eradication of H. pylori can reduce the incidence rate of CSX, especially in middle-aged individuals and some developing countries.

Associations of lung cancer risk with biomarkers of Helicobacter pylori infection

Helicobacter pylori infection has been suggested to be associated with lung cancer risk. However, information is lacking on whether the association differs by H. pylori antigen. We conducted a nested case-control study within the Southern Community Cohort Study, including 295 incident lung cancer cases and 295 controls. Helicobacter pylori multiplex serology assay was performed to detect antibodies to 15 H. pylori proteins. Conditional logistic regression was used to estimate odds ratios (ORs) and confidence intervals (95% CIs) after adjustment for covariates. Overall H. pylori+ was associated with a non-statistically significant increased risk of lung cancer (OR: 1.29; 95% CI: 0.85-1.95). Significant associations, however, were observed for H. pylori+ VacA+ (OR: 1.64; 95% CI: 1.02-2.62) and H. pylori+ Catalase+ (OR: 1.75; 95% CI: 1.11-2.77). The positive association of H. pylori+ Catalase+ with lung cancer risk was predominantly seen among African Americans (OR: 2.09; 95% CI: 1.11-3.95) but not European Americans (OR: 1.20; 95% CI: 0.56-2.54). Among participants who smoked ≥ 30 pack-years, overall H. pylori+ (OR: 1.85; 95% CI: 1.02-3.35), H. pylori+ CagA+ (OR: 2.77; 95% CI: 1.35-5.70), H. pylori+ VacA+ (OR: 2.53; 95% CI: 1.25-5.13) and H. pylori+ HP1564+ (OR: 2.01; 95% CI: 1.07-3.77) were associated with increased risk of lung cancer. Our study provides novel evidence that associations of H. pylori infection with lung cancer risk differ by H. pylori biomarker, may be more evident among African Americans and may be modified by smoking habits. Furthermore, studies are warranted to confirm our findings.

Microbiome Crosstalk in Immunotherapy and Antiangiogenesis Therapy

The human body and its microbiome constitute a highly delicate system. The gut microbiome participates in the absorption of the host's nutrients and metabolism, maintains the microcirculation, and modulates the immune response. Increasing evidence shows that gut microbiome dysbiosis in the body not only affects the occurrence and development of tumors but also tumor prognosis and treatment. Microbiome have been implicated in tumor control in patients undergoing anti- angiogenesis therapy and immunotherapy. In cases with unsatisfactory responses to chemotherapy, radiotherapy, and targeted therapy, appropriate adjustment of microbes abundance is considered to enhance the treatment response. Here, we review the current research progress in cancer immunotherapy and anti- angiogenesis therapy, as well as the unlimited potential of their combination, especially focusing on how the interaction between intestinal microbiota and the immune system affects cancer pathogenesis and treatment. In addition, we discuss the effects of microbiota on anti-cancer immune response and anti- angiogenesis therapy, and the potential value of these interactions in promoting further research in this field.

Rheumatic Heart Disease and Its Association with H. pylori Infection

Acute rheumatic fever (ARF) triggered by Group A streptococcus bacterium due to post-infectious and non-supportive pharyngeal infection. Depending on certain conditions, such as genetic predisposition to the disease, the prevalence of various cases of rheumatism and socioeconomic status in different regions, ARF can have different clinical manifestations. The disease typically manifested by one or more acute episodes, whereas 30-50% of all repeated ARF status can result in chronic rheumatic heart disease (RHD) with gradual and irreversible heart valve damage and also have been found to be correlated with a raised risk of myocardial infarction (MI), cardiovascular disease (CVD) and dyslipidemia. The RHD is the only long-term consequence of ARF and the most serious. The development to chronic RHD is determined by many factors, most notably the frequent episodes of rheumatic fever (RF). The RHD is known socially and economically as being the most frequent heart disease in vulnerable populations. H.pylori infection has been proposed to be involved RHD greater than that of the normal healthy people. H.pylori can be considered as one of the probable risk factor for RHD.It was concluded that patients with H. Pylori should be advised to follow up in cardiology clinics to avoid any complications.

Metagenomic sequencing and evaluation of the host response in the pediatric aerodigestive population

OBJECTIVES

To assess the diagnostic utility of metagenomic sequencing in pediatric aerodigestive clinic patients being evaluated for chronic aspiration. We hypothesize that using a metagenomics platform will aid in the identification of microbes not found on standard culture.

STUDY DESIGN AND METHODS

Twenty-four children referred to an aerodigestive clinic were enrolled in a prospective, single-site, cross-sectional cohort study. At the time of clinical evaluation under anesthesia, two samples were obtained: an upper airway sample and a sample from bronchoalveolar lavage (BAL). Samples were sent for routine culture and analyzed using Explify® Respiratory, a CLIA Laboratory Developed Test which identifies respiratory commensals and pathogens through RNA and DNA sequencing. Since RNA was sequenced in the course of the metagenomic analysis to identify organisms (RNA viruses and bacteria), the sequencing approach also captured host derived messenger RNA during sample analysis. This incidentally obtained host transcriptomic data were analyzed to evaluate the host immune response. The results of these studies were correlated with the clinical presentation of the research subjects.

RESULTS

In 10 patients, organisms primarily associated with oral flora were identified in the BAL. Standard culture was negative in three patients where clinical metagenomics led to a result with potential clinical significance. Transcriptomic data correlated with the presence or absence of dysphagia as identified on prior videofluoroscopic evaluation of swallowing.

CONCLUSIONS

Clinical metagenomics allows for simultaneous analysis of the microbiota and the host immune response from BAL samples. As the technologies in this field continue to advance, such testing may improve the diagnostic evaluation of patients with suspected chronic aspiration.

Network pharmacology to dissect the mechanisms of Yinlai Decoction for pneumonia

BACKGROUND

Pneumonia is a common respiratory disorder, which brings an enormous financial burden to the medical system. However, the current treatment options for pneumonia are limited because of drug resistance and side effects. Our previous study preliminarily confirmed that Yinlai Decoction (YD), a common prescription for pneumonia in clinical practice, can regulate the expression of inflammatory factors, but the mechanisms are unknown yet.

METHODS

In our work, a method named network pharmacology was applied, which investigated the underlying mechanisms of herbs based on a variety of databases. We obtained bioactive ingredients of YD on TCMSP database and collected potential targets of these ingredients by target fishing. Then the pneumonia-related targets database was built by TTD, Drugbank, HPO, OMIM, and CTD. Based on the matching targets between YD and pneumonia, the PPI network was built by STRING to analyze the interactions among these targets and then input into Cytoscape for further topological analysis. DAVID and KEGG were utilized for GO and pathway enrichment analysis. Then rat model based on LPS stimulated pneumonia was used to verify the possible mechanism of YD in treating pneumonia.

RESULTS

Sixty-eight active ingredients, 103 potential targets and 8 related pathways, which likely exert a number of effects, were identified. Three networks were constructed using Cytoscape, which were herb-component-network, YD-pneumonia target network, and herb-component-YD target-pneumonia network. YD was verified to treat LPS-induced pneumonia by regulating the inflammatory factor IL-6, which was a predicted target.

CONCLUSION

Network analysis indicated that YD could alleviate the symptoms and signs of pneumonia through regulating host immune inflammatory response, angiogenesis and vascular permeability, the barrier function of the airway epithelial cells, hormone releasing and cell growth, proliferation, and apoptosis.

Human Lung Microbiome on the Way to Cancer

Recent research on cancer-associated microbial communities led to the accumulation of data on the interplay between bacteria, immune and tumor cells, the pathways of bacterial induction of carcinogenesis, and its meaningfulness for medicine. Microbial communities that have any kind of impact on tumor progression and microorganisms associated with tumors have been defined as oncobiome. Over the last decades, a number of studies were dedicated to Helicobacter pylori and its role in the progression of stomach tumors, so this correlation can be regarded as proven. Involvement of bacteria in the induction of lung cancer has been largely ignored for a long time, though some correlations between this type of cancer and lung microbiome were established. Despite the fact that in the present the microbial impact on lung cancer progression has many confirmations, the underlying mechanisms are poorly understood. Microorganisms can contribute to tumor initiation and progression through production of bacteriotoxins and other proinflammatory factors. The purpose of this review is to organize the available data on lung cancer microbiome and its role in malignant tumor progression.

Association of endothelial dysfunction and cytotoxin-associated gene A-positive Helicobacter pylori in patients with cardiac syndrome X

Background

Existence of coronary endothelial dysfunction has been demonstrated in patients with cardiac syndrome X (CSX). In addition, Helicobacter pylorus (H. pylori) has been associated with CSX. We aimed to assess the possible association of endothelial dysfunction and cytotoxin-associated gene A-positive H. pylori (CagA+) infection in CSX patients.

Methods

Fifty-six patients with CSX (23 male/33 female; age: 51.25 ± 8.86 years) who were anti-H. pylori IgG-positive [H. pylori(+)] and 24 CSX patients (7 male/17 female; age: 52.79 ± 9.88 years) who were H. pylori(−) were included. Also, anti-H. pylori IgG-positive patients were determined by the presence of IgG antibody to CagA. Levels of endothelin-1 (ET-1), E-selectin and intercellular adhesion molecule-1 (ICAM-1) were measured.

Results

Endothelial dysfunction biomarkers were higher in H. pylori(+) than in H. pylori(−) patients (ET-1: 54.60 ± 25.39 vs. 42.59 ± 18.37 pg/ml, p = 0.04; E-selectin: 42.68 ± 14.26 vs. 31.72 ± 8.26 ng/ml, p = 0.001; ICAM-1: 339.68 ± 135.8 vs. 266.51 ± 125.1 ng/ml, p = 0.02). Among H. pylori(+) subjects, 28 cases were CagA(+) and 28 cases were CagA(−). There were significant differences in measured levels of E-selectin between CagA(+) and CagA(−) groups (48.00 ± 16.37 vs. 37.37 ± 9.37 ng/ml, p = 0.004). For ET-1 and ICAM-1 levels, the difference between CagA(+) and CagA(−) was insignificant (p = 0.174 and p = 0.07, respectively).

Conclusion

High levels of endothelial dysfunction biomarkers are found in CSX patients with anti-CagA(+). These findings suggest the infection with CagA(+) H. pylori strain may play a role as a risk factor in development of CSX through provocation of endothelial dysfunction. Therefore, a long term follow up to investigate the outcomes of these patients is proposed.

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.

Detection of Helicobacter pylori in the Bronchoalveolar Lavage of Patients with Lung Cancer Using Real-Time PCR

Background

Lung cancer is one of the most common causes of death worldwide. Although smoking and environmental pollutants are the most important risk factors of lung cancer, the role of infectious causes should also be considered in the pathogenesis and progress of lung cancer.

Objectives

This study examined the relationship between Helicobacter pylori and lung cancer through serology, real-time PCR, and urease tests.

Methods

This descriptive cross-sectional study was conducted on 52 adult patients with lung cancer who were selected after having their history taken and being physically examined by a pulmonologist. Then, the patients underwent a bronchoscopy, a BAL, and biopsy sampling. A urease test was run for each biopsy sample, real-time PCR was used for each BAL sample, and H. pylori serology was used for each patient’s serum.

Results

The patients’ average age was 60.65 ± 9.15 years; 11.5% were female and 88.5% were male. The prevalence of H. pylori in lung cancer patients was 11.5% according to the BAL PCR test, 92.3% according to the serology test, and 3.8% according to the urease test.

Conclusions

The results demonstrated an association between of lung cancer and H. Pylori infection via the hypothesis of direct damage and chronic inflammation through inhalation and aspiration and the systematic immune response induced by H. pylori colonization. Helicobacter pylori, together with a host’s genetic predisposition and other environmental risk factors, could be attributed to the induction of lung cancer.

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.

Helicobacter pylori seroprevalence in children with sleep-disordered breathing

OBJECTIVE

Chronic Helicobacter pylori (HP) infection is considered to be a factor involved in obstructive sleep apnea syndrome (OSAS). This cross-sectional study examined the seroprevalence of HP in children with sleep-disordered breathing (SDB) in respect to OSAS severity and in reference to other common pediatric medical conditions.

METHODS

Overnight polysomnography with pH-metry (PSG) was performed at a Sleep Laboratory (in the years 2008-2011). OSAS severity was determined based on Obstructive Apnea Index (OAI). Subjects were classified into primary snoring group (OAI < 1/hours), mild - moderate OSAS (OAI: 1-5/hour), and severe OSAS (OAI: ≥5/hour). HP IgG was tested by an enzyme-linked immunosorbent assay in the SDB (n = 115) and reference (n = 387) groups [reference group consisted of 4 subgroups based on ICD-10 diagnoses encompassing conditions affecting the skin, respiratory system, food hypersensitivity, and gastrointestinal tract]. Analyses were performed by nonparametric statistical tests.

RESULTS

HP seropositivity was 10.4% (12/115) in the SDB group and 11.6% (45/387) in the reference group. HP positive and negative subjects did not differ in PSG, acid gastro-esophageal reflux index nor in age, sex, nutritional status (BMI-z score), and hematological indices in the SDB group. Seropositivity was found in 16.7% of the primary snoring group, 10.2% of mild-moderate OSAS, and in 11.1% of severe OSAS (chi(2) p = 0.832).

CONCLUSIONS

Children with SDB are not more predisposed to a chronic HP infection than children with other common chronic pediatric conditions. HP seropositivity does not influence OSAS severity but possible infection should none-the-less be considered on a case-by-case basis.

Screening for Helicobacter pylori in Idiopathic Pulmonary Fibrosis Lung Biopsies

BACKGROUND

Increasing evidence suggests a role of gastro-oesophageal reflux (GER) in idiopathic pulmonary fibrosis (IPF) pathogenesis. Recently, an association between serum Helicobacter pylori (HP) antibody positivity and more severe disease was described, but HP has not been directly analysed in lung tissue so far.

OBJECTIVE

To investigate the presence of HP in the lung tissue of IPF patients.

METHODS

Two tertiary interstitial lung disease care centre databases were screened for available lung biopsy material from IPF patients. Clinical and radiological data, including presence of GER and antiacid medication, were evaluated. HP-specific PCR was carried out on the IPF lung biopsy specimens.

RESULTS

A total of 39 IPF patients were included, of whom 85% were male. The patients' median age was 66 years, their vital capacity was 79% predicted, and their diffusing capacity for carbon monoxide was 53% predicted. In all, 82% of the lung biopsies were surgical and 18% transbronchial. Comorbidities were GER disease in 23% (n = 9), sleep apnoea in 13% (n = 5) and hiatal hernia in 38% of the cases (n = 15). Proton pump inhibitors were prescribed at the time of biopsy in 21% of the cases (n = 9). After a median follow-up of 25 months (range 6-69), there were 1 death, 1 lung transplantation and 8 acute exacerbations without relevant differences between the GER and non-GER subgroups. HP DNA was not detected in any of the lung tissue samples.

CONCLUSION

The fact that no HP DNA was detected in the lung tissues calls into question the proposed relevance of HP to the direct pathogenesis of IPF.

Increased risk of chronic obstructive pulmonary disease among patients with Helicobacter pylori infection: a population-based cohort study

BACKGROUND

Increasing evidence suggests that Helicobacter pylori infection (HPI) may have extragastric manifestations, including the respiratory system. This study investigated the role of HPI in increasing the subsequent risk of chronic obstructive pulmonary disease (COPD) in a nationwide population.

METHODS

We conducted this retrospective cohort study using data from the Longitudinal Health Insurance Database, which is derived from the Taiwanese National Health Insurance Research Database. A total of 5941 adults who were newly diagnosed with HPI between 2005 and 2006 were selected. Healthy patients without HPI were selected from the general population and frequency matched as a ratio of 4:1, according to age, sex, and index years. Both cohorts were followed up from the index date to the end of 2011 to measure the incidence of COPD. Cox proportional hazard regression analysis was used to assess the hazard ratio (HR) of COPD between the HPI cohort and non-HPI cohorts.

RESULTS

The overall HR of COPD was 1.84 (95% confidence intervals = 1.57-2.17) for the HPI cohort, compared with the non-HPI cohort, after adjusting for age, sex, and comorbidities. Although the incidence of COPD was substantially higher in the elderly participants (age, ≥ 65 years) than that in younger participants, the highest HR (4.05, 95% confidence intervals = 1.39-11.8) of COPD was observed in the youngest (age, 20-49 years) participants.

CONCLUSION

In this study, the patients with HPI exhibited a significantly higher risk of COPD than those without HPI did.

The effect of Helicobacter pylori eradication on proteinuria in patients with primary glomerulonephritis

INTRODUCTION

Glomerulonephritis is still the primary cause among the diseases causing end stage renal disease. Helicobacter pylori (HP), also having a local proinflammatory effect on gastric mucosa, can trigger a local and systemic inflammatory response, and consequently have a role in the development of extragastrointestinal defects.

MATERIAL AND METHODS

The study was composed of patients diagnosed with primary glomerulonephritis who had dyspeptic complaints throughout the diagnosis. Patients who received endoscopic biopsy upon the determination of pathologic findings in their upper gastrointestinal endoscopy were HP positive in their biopsy material. A triple eradication therapy was initiated for HP.

RESULTS

The study included 14 female and 19 male patients, 33 in total, whose biopsy material was determined to be HP positive. Before the eradication for HP, we found serum albumin to be 34.0 (19.0-51.0) g/l, serum total protein 58.6 ±12.9 g/l, serum creatinine 0.9 (0.5-1.2) and proteinuria 3069 (652-12392) mg/day in 24-hour urine. After the eradication, however, serum albumin was found to be 40 (20-52) g/l, serum total protein 62.3 ±11.1 g/l, serum creatinine 1.02 (0.6-1.29) mg/dl and proteinuria was 2850 (172-15181) mg/day in 24-hour urine. A comparison of the results showed that a statistically significant difference is established between the serum albumin, total protein and creatinine values (p = 0.001, p = 0.001 and p = 0.021, respectively), but not between proteinuria values in 24-hour urine (p = 0.990).

CONCLUSIONS

Patients with primary glomerulonephritis, HP eradication treatment has an effect on serum albumin levels.

Association Between Chronic Respiratory Diseases and Helicobacter pylori: A Meta-Analysis

BACKGROUND

The prevalence of chronic respiratory diseases (CRDs), including chronic bronchitis and chronic obstructive pulmonary disease (COPD), has increased significantly over the past decades. Several studies suggest that Helicobacter pylori infection may be related to the development of CRDs, but the results were not consistent. We carried out a meta-analysis to evaluate the potential association of H.pylori infection with CRDs.

METHODS

We conducted a systematic literature search in PubMed, Embase, Ovid, Google Scholar and CNKI from inception to October 31, 2013. The following search terms were used: "chronic respiratory disease," "chronic bronchitis," "chronic obstructive pulmonary disease" or "COPD" in combination with "Helicobacter pylori" or "Campylobacter pylori." According to established inclusion criteria, we selected all eligible published papers and then extracted essential data. To evaluate the association of H.pylori with chronic bronchitis and COPD, an overall analysis and subgroup analyses were conducted.

RESULTS

A total of 9 case-control studies comprising 782 cases and 815 controls were included in the study. Pooled ORs were 2.30 (95%CI: 1.85-2.85) in the overall analysis, 2.90 (95%CI: 2.04-4.13) in the chronic bronchitis subgroup, and 2.11 (95%CI: 1.35-3.29) in the COPD subgroup.

CONCLUSIONS

The results of the overall analysis and subgroup analyzed suggest a significant association between H.pylori and CRDs. Further studies are needed to clarify the pathogenetic mechanisms involved.

Helicobacter pylori infection and lung cancer: a review of an emerging hypothesis

Helicobacter pylori (Hp) is one of the most common bacteria infecting humans. Recently, certain extragastric manifestations, linked to Hp infection, have been widely investigated, suggesting that Hp infection might be a 'systemic' disease. Accumulating, yet limited, evidence points to a potential association between Hp infection and lung cancer risk. Epidemiologic studies have shown that odds ratios (estimated relative risks) of lung cancer with Hp infection range from 1.24 to 17.78 compared with the controls, suggesting an increased lung cancer risk in the population exposed to Hp infection although far from supporting a causal relationship between Hp and lung cancer. Many studies have demonstrated the existence of Hp in the mucosa of the upper respiratory tract with no direct evidence of Hp-localization in lung tissue in the published literatures, rendering the possible functional mechanism underlying the association an open question. We followed the classic hypothesis-generating path, where we have thoroughly reviewed the publications on lung cancer and Hp infection from serological association to possible mechanisms as: (i) p130cas activated by Src kinase following Hp-host communication and p130cas-related carcinogenesis as in various malignancies; and (ii) gastroesophageal reflux and inhalation of urease or gastrin, which are Hp-related carcinogenic factors and present in lung tissues. We propose rigorous investigations regarding the Hp-lung cancer association and, if confirmed, the mechanisms of Hp infection leading to lung cancer development and progression. Clarification on Hp-lung cancer association is important for the understanding of lung cancer beyond tobacco-smoking-related carcinogenesis.

Helicobacter pylori Infection and Risk of Lung Cancer: A Meta-Analysis

Background. Recent evidence showed that Helicobacter pylori seropositivity is a risk factor for gastric and several other cancers. However, evidence on H. pylori infection and risk of lung cancer has been controversial, with a limited number of underpowered studies. We therefore examined the association between H. pylori infection and risk of lung cancer. Methods. A comprehensive literature search was performed using PubMed, EMBASE (until October 2012) for studies investigating an association between Helicobacter pylori (H. pylori) infection and risk of lung cancer. Pooled odds ratio (OR) was calculated using random-effects model. Subgroup and sensitivity analysis were also done. Results. A total of seven studies (6 case-control and 1 cohort study) were included for the analysis. There was a significant heterogeneity among the studies, but no publication bias was observed. We found that H. pylori infection was associated with significantly increased risk of lung cancer (pooled OR, 2.29 (95% CI, 1.34–3.91) P = 0.01). Conclusions. Our meta-analysis suggests a significant increased risk of lung cancer in patients with H. pylori infection. Further research is needed to confirm these findings and to identify the underlying biological mechanisms.

Urease and Helicobacter spp. antigens in pulmonary granuloma

Pulmonary sarcoidosis, a human disease of unknown cause, has no animal model. Sarcoidosis patients have serum antibodies specific for Helicobacter pylori and its surface enzyme urease. H. pylori do not survive in the high-oxygen pulmonary atmosphere, but urease may access the lung by oesophageal reflux. A model was established in rats to study gastro-oesophageal reflux of urease into the airways. Pathology in tissues from human sarcoidosis patients was compared with that in the rat model. Changes observed in the rat model included prominent peribronchial lymphocytic infiltration, which is seen occasionally in human sarcoidosis. Granulomas, pathognomonic for human sarcoidosis, occurred occasionally in the lungs of rats given urease protein intratracheally, but were widespread when urease was coupled to microbeads and administered intravenously. Biomarkers associated with human sarcoidosis (interleukin1-β and platelet-activating factor) were up-regulated acutely in the rat model. Further investigations with this model may provide significant insights into the origin and pathogenesis of pulmonary diseases in man and other species that carry gastric Helicobacter spp. and its associated enzyme.

Association of inflammation and cytotoxin-associated gene a positive strains of helicobacter pylori in cardiac syndrome x

BACKGROUND

Cardiac syndrome X (CSX) is a condition in which patients have the pain of angina despite normal coronary angiogram. Helicobacter pylori (H. pylori) infection causes chronic inflammation which may play a pathogenic role in CSX. We surveyed the association of inflammation with H. pylori and its virulent strain (cytotoxin-associated gene A positive; CagA+) infections with CSX.

MATERIAL AND METHODS

Sixty patients with CSX (38 women/22 men; mean age: 51.8 ± 12.3) and 60 age- and gender-matched healthy controls (39 women/21 men; mean age: 48.9 ± 6.3) were enrolled. Plasma samples were tested for the presence of IgG antibody to H. pylori using enzyme linked immunosorbent assay (ELISA) method. IgG- positive patients were determined by the presence of IgG antibody to CagA, also by ELISA method. Also, plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were measured by ELISA method.

RESULTS

Patients with CSX were detected to have significantly higher plasma IL-6 and TNF-α level in comparison with normal controls (33.6 ± 3.5 vs 3.2 ± 0.4 and 24.2 ± 2.3 vs 3.1 ± 0.4, respectively; p < 0.01). The plasma levels of these inflammatory factors in CgA+ were significantly higher than those in CagA- (CSX: IL-6: 43.05 ± 5.04 vs 23.97 ± 4.58 and TNF-α: 31.43 ± 3.13 vs 16.47 ± 2.93, CONTROLS: IL-6: 3.52 ± 1.39 vs 2.90 ± 0.67 and TNF-α: 5.39 ± 1.17 vs 2.22 ± 0.43, respectively; p < 0.05).

CONCLUSION

The CagA+ strain of H. pylori, can not only be a trigger, and may also have a role via chronic inflammation in the pathogenesis of CSX.

Helicobacter pylori seropositivity and risk of lung cancer

Lung cancer is the leading cause of cancer mortality worldwide. Helicobacter pylori (H. pylori) is a risk factor for distal stomach cancer, and a few small studies have suggested that H. pylori may be a potential risk factor for lung cancer. To test this hypothesis, we conducted a study of 350 lung adenocarcinoma cases, 350 squamous cell carcinoma cases, and 700 controls nested within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC) cohort of male Finnish smokers. Controls were one-to-one matched by age and date of baseline serum draw. Using enzyme-linked immunosorbent assays to detect immunoglobulin G antibodies against H. pylori whole-cell and cytotoxin-associated gene (CagA) antigens, we calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations between H. pylori seropositivity and lung cancer risk using conditional logistic regression. H. pylori seropositivity was detected in 79.7% of cases and 78.5% of controls. After adjusting for pack-years and cigarettes smoked per day, H. pylori seropositivity was not associated with either adenocarcinoma (OR: 1.1, 95% CI: 0.75–1.6) or squamous cell carcinoma (OR: 1.1, 95% CI: 0.77–1.7). Results were similar for CagA-negative and CagA-positive H. pylori seropositivity. Despite earlier small studies suggesting that H. pylori may contribute to lung carcinogenesis, H. pylori seropositivity does not appear to be associated with lung cancer.

Future candidates for indications of Helicobacter pylori eradication: do the indications need to be revised?

Since the discovery of Helicobacter pylori in 1982, the development of several treatment guidelines has allowed a consensus on the indications for H. pylori eradication. Beyond these currently accepted indications, including various upper gastrointestinal disorders and extragastric diseases, a significant amount of new information regarding H. pylori eradication is emerging. Certain types of acute gastritis, such as nodular gastritis, hypertrophic gastritis, Ménétrier's disease, hemorrhagic gastritis, and granulomatous gastritis are reversible after H. pylori eradication. Further, for chronic gastritis, closed-type atrophic gastritis and complete-type intestinal metaplasia appear to be more reversible after H. pylori eradication than open-type atrophic gastritis and incomplete-type intestinal metaplasia. Eradication can also be considered in subjects younger than 40 years who have a family history of gastric cancer and in subjects with long-term medications that might lead to bleeding (antiplatelet agents) or atrophy (proton pump inhibitors). Emerging evidence indicates that H. pylori eradication could be an effective treatment for some extragastric diseases that are unresponsive to conventional therapy. In such conditions, routine screening for eradication of H. pylori has not previously been recommended; a "test-and-treat" approach is suggested in the aforementioned situations. Given that H. pylori eradication is effective when the gastritis is reversible, future indications should be expanded to include acute gastric lesions that show marked improvement upon H. pylori eradication rather than just focusing on chronic gastric lesions. Future indications for H. pylori eradication should focus more on reversible lesions before preneoplastic conditions develop.

Is Helicobacter pylori infection associated with asthma risk? A meta-analysis based on 770 cases and 785 controls

OBJECTIVE

Helicobacter pylori (H. pylori) infection has been thought to play a critical role in disorders such as gastric and lung cancer. A number of studies have been devoted to the relationship between H. pylori infection and asthma risk, which have generated inconclusive results. In this study we aimed to derive a more precise estimation of the relationship.

METHODS

Meta-analyses evaluating the association of H. pylori infection and asthma risk were conducted and subgroup analyses on ethnicity and source of controls as well as CagA status were further conducted. Eligible studies were identified for the period up to Jul 2012.

RESULTS

A total of five case-control studies comprising 770 cases and 785 controls were lastly selected for analysis. The overall data failed to indicate a significant association of H. pylori infection and asthma risk (OR=1.01; 95%CI=0.82-1.24). Likewise, in the subgroup analysis regarding ethnicity, source of controls and CagA status, no associations could be observed.

CONCLUSIONS

The pooled data failed to suggest a marked association between H. pylori infection and asthma risk. Future studies are needed to confirm this conclusion.

Association between Helicobacter pylori Seropositivity and the Coronary Artery Calcium Score in a Screening Population

BACKGROUND/AIMS

Helicobacter pylori causes numerous extragastric manifestations, including coronary heart disease. The coronary artery calcification (CAC) score, measured using computed tomography (CT) has been used as a screening test for coronary atherosclerosis. This study investigated the association between H. pylori seropositivity and CAC scores in a screening population.

METHODS

Patients who underwent a health checkup between October 2003 and July 2007 and who did not have a history of ischemic heart disease were enrolled in the study. Subjects were screened with a multidetector CT scan to determine the CAC score and for anti-H. pylori antibody immunoglobulin G; traditional risks for coronary heart disease were evaluated using a structured questionnaire, anthropometric measurements, and laboratory tests.

RESULTS

Of the 2,029 subjects enrolled (1,295 males), 1,214 (59.8%) subjects were H. pylori positive and 815 were H. pylori negative. There were no significant differences in the baseline characteristics of the seropositive and seronegative patients. When the CAC presence or absence scores were considered, multivariate analysis revealed that H. pylori seropositivity was statistically associated with the presence of CAC and that this association was stronger in the mild CAC score category.

CONCLUSIONS

H. pylori seropositive patients are at a higher risk for coronary atherosclerosis regardless of traditional cardiovascular risk factors. This association is particularly applicable for early coronary atherosclerosis.

Association between Helicobacter pylori Seropositivity and the Coronary Artery Calcium Score in a Screening Population

BACKGROUND/AIMS

Helicobacter pylori causes numerous extragastric manifestations, including coronary heart disease. The coronary artery calcification (CAC) score, measured using computed tomography (CT) has been used as a screening test for coronary atherosclerosis. This study investigated the association between H. pylori seropositivity and CAC scores in a screening population.

METHODS

Patients who underwent a health checkup between October 2003 and July 2007 and who did not have a history of ischemic heart disease were enrolled in the study. Subjects were screened with a multidetector CT scan to determine the CAC score and for anti-H. pylori antibody immunoglobulin G; traditional risks for coronary heart disease were evaluated using a structured questionnaire, anthropometric measurements, and laboratory tests.

RESULTS

Of the 2,029 subjects enrolled (1,295 males), 1,214 (59.8%) subjects were H. pylori positive and 815 were H. pylori negative. There were no significant differences in the baseline characteristics of the seropositive and seronegative patients. When the CAC presence or absence scores were considered, multivariate analysis revealed that H. pylori seropositivity was statistically associated with the presence of CAC and that this association was stronger in the mild CAC score category.

CONCLUSIONS

H. pylori seropositive patients are at a higher risk for coronary atherosclerosis regardless of traditional cardiovascular risk factors. This association is particularly applicable for early coronary atherosclerosis.

Expression of inflammatory mediators in the otitis media induced by Helicobacter pylori antigen in mice

Helicobacter pylori is a Gram-negative bacterium that is recognized as one of the key factors in gastric diseases such as gastritis, peptic ulcer and gastric cancer. Recent studies have shown relationships between H. pylori and extra-digestive diseases, and the presence of H. pylori in the middle ear and upper respiratory tract has been reported. However, the role of H. pylori in middle ear disease remains unclear. The present study demonstrated that H. pylori whole-cell protein directly induces macrophage migration inhibitory factor, macrophage inflammatory protein 2, interleukin 1 beta and tumor necrosis factor alpha in middle ear epithelium in mice, and severe proliferation of inflammatory cells was observed in middle ear cavity inoculated with H. pylori whole-cell protein. In addition, trans-tympanic injection of macrophage migration inhibitory factor up-regulated expression of macrophage inflammatory protein 2 in the middle ear. These findings indicate that H. pylori infection causes immunological inflammation in middle ear epithelium, and H. pylori may play a significant role in otitis media.

[Does Helicobacter pylori infection play a role in extragastric diseases?]

Since the discovery of Helicobacter pylori (H. pylori), numerous studies have considered the possibility that it plays a role in different extragastric diseases. Most of these studies may be classified as epidemiological studies or investigations of H. pylori eradication, but there are also case reports and in vitro studies. This review reveals the limitations common to most of them. Idiopathic thrombocytopenic purpura is the disease for which the strongest association with H. pylori infection has been shown. Data are also accumulating about the role of H. pylori infection in idiopathic iron deficiency anemia and chronic idiopathic urticaria. Interesting results show that H. pylori infection affects atherosclerosis and is weakly associated with ischemic heart disease and stroke. Moreover, CagA-positive H. pylori strains may play a role in the natural history of atherosclerotic stroke. Recent studies suggest a link between H. pylori and Parkinson's disease. Preliminary data indicate that H. pylori infection impairs gastric ghrelin production and may influence nutritional status. The association between H. pylori infection and other extragastric diseases remains controversial. H. pylori infection may cause extragastric manifestations directly or indirectly, by various mechanisms including atrophic gastritis, the release of inflammatory mediators, molecular mimicry, and systemic immune response. Evidence suggests that anti-H. pylori therapy improves idiopathic thrombocytopenic purpura (significant increase of platelet count in half of the cases), iron-deficiency anemia, and chronic urticaria (30% remission rate), but the data from randomized controlled trials are insufficient to confirm these positive effects.