Helicobacter pylori colonization of the adenotonsillar tissue: fact or fiction?

Prevalence of Helicobacter pylori in routine adult tonsillectomies

Helicobacter pylori, a curved bacterial rod and causative agent of peptic ulcer and gastric adenocarcinoma, is found as an infectious agent in the stomach of over half of the global population. H. pylori has been identified in oral biofilms and its presence in adenotonsillar tissues has been suggested, with variations in testing methodology both proving and disproving its presence. The current study employed 119 formalin-fixed paraffin-embedded tonsillar tissues from an adult population (n=86) in a major metropolitan city with immunohistochemistry procedures using a monoclonal antibody to determine the incidence of H. pylori in the tonsils. H. pylori was identified in 72.1% of the patients and was associated with Actinomyces spp. in 92.0% of those cases. The high incidence of H. pylori in patients undergoing tonsillectomy suggests that H. pylori may be a contributing factor for tonsillitis and tonsillar hypertrophy. Furthermore, the reservoir for H. pylori in the tonsils may explain why some persons remain refractory to antibiotic treatment for gastric H. pylori.

Unveiling the Enigmatic Adenoids and Tonsils: Exploring Immunology, Physiology, Microbiome Dynamics, and the Transformative Power of Surgery

Within the intricate realm of the mucosal immune system resides a captivating duo: the adenoids (or pharyngeal tonsils) and the tonsils (including palatine, tubal, and lingual variations), which harmoniously form the Waldeyer's ring. As they are strategically positioned at the crossroads of the respiratory and gastrointestinal systems, these exceptional structures fulfill a vital purpose. They function as formidable "gatekeepers" by screening microorganisms-both bacteria and viruses-with the mission to vanquish local pathogens via antibody production. However, under specific circumstances, their function can take an unsettling turn, inadvertently transforming them into reservoirs for pathogen incubation. In this review, we embark on a fascinating journey to illuminate the distinctive role of these entities, focusing on the local immune system inside their tissues. We delve into their behavior during inflammation processes, meticulously scrutinize the indications for surgical intervention, and investigate the metamorphosis of their microbiota in healthy and diseased states. We explore the alterations that occur prior to and following procedures like adenoidectomy, tonsillectomy, or their combined counterparts, particularly in pediatric patients. By comprehending a wealth of data, we may unlock the key to the enhanced management of patients with otorhinolaryngological disorders. Empowered with this knowledge, we can embrace improved therapeutic approaches and targeted interventions/surgeries guided by evidence-based guidelines and indications.

Possible Role of Helicobacter pylori in Ear Nose and Throat Diseases

Background

Helicobacter pylori is assumed to cause many gastric and extragastric diseases. We aimed to assess the possible association role of H. pylori in Otitis media with effusion (OME), nasal polyps and adenotonsillitis.

Patients and Methods

A total of 186 patients with various ear, nose and throat diseases were included. The study comprised 78 children with chronic adenotonsillitis, 43 children with nasal polyps and 65 children with OME. OME patients were assigned to two subgroups: those who have and those who did not have adenoid hyperplasia. Among the patients with bilateral nasal polyps, 20 individuals had recurrent nasal polyps and 23 had de novo nasal polyps. Patients who have chronic adenotonsillitis were divided into three groups: those with chronic tonsillitis and those who underwent tonsillitis, those with chronic adenoiditis and adenoidectomy was performed, and those with chronic adenotonsillitis and underwent adenotonsillectomy. In addition to examination of H. pylori antigen in stool samples of all included patients, real-time polymerase chain reaction (RT-PCR) for detection of H. pylori in the effusion fluid was performed, additionally, Giemsa stain was used for detection of H. pylori organism within the tissue samples when available.

Results

Frequency of H. pylori in effusion fluid was 28.6% in patients with OME and adenoid hyperplasia, while in those with OME it was only 17.4% with a p value of 0.2. Nasal polyp biopsies were positive in 13% patients of denovo, and 30% patients with recurrent nasal polyps, p=0.2. De novo nasal polyps were more prevalent in the positive stools than recurrent ones, p=0.7. All adenoid samples were negative for H. pylori, only two samples of tonsillar tissue (8.3%) were positive for H. pylori, and stool analysis was positive in 23 patients with chronic adenotonsillitis.

Conclusion

Lack of association between Helicobacter pylori and occurrence of OME, nasal polyposis or recurrent adenotonsillitis.

The role of Helicobacter Pylori and laryngopharyngeal reflux in recurrent tonsillitis

OBJECTIVES

To detect Helicobacter Pylori [HP] in tonsillar tissue of recurrent tonsillitis cases and assess the possible role of Laryngopharyngeal reflux [LPR] in tonsillar HP infection.

METHODS

A prospective study was done on the cited subject in a sample size of 50 paediatric patients [Age group: 6-18 years] suffering from recurrent tonsillitis. LPR was diagnosed by Reflux Symptom index [RSI] and Reflux Finding score [RFS]. A score of more than 7 and 13 was regarded as significant for RFS and RSI respectively. Patients with both scores significant were regarded to be suffering from LPR. Tonsillar specimen after tonsillectomy were subjected to urease test, histopathology [ Modified Giemsa Staining] and culture to detect HP. A minimum of two positive tests of the mentioned three were taken as gold standard to diagnose colonization of HP. Tabulated data was statistically analysed.

RESULTS

We recorded an incidence of 9% [18 cases] for LPR in recurrent tonsillitis. No case of HP colonization of tonsils was detected in this case series, even in patients of LPR.

CONCLUSION

We conclude that tonsils are not an extra gastric reservoir of HP. In addition, there is no aetiological relationship between recurrent tonsillitis and HP. And lastly, LPR is not a significant factor for colonization of tonsils by HP.

Helicobacter pylori in Otorhinolaryngology: Cause or Bystander

The bacteria Helicobacter pylori (H. pylori) have been identified in the extragastric tissues in the head and neck. The origin and pathogenicity of these bacteria in the head and neck are not known. Gastric reflux and nasal or oral routes are the possible modes of spread. In many sinonasal, pharyngeal, laryngeal, and middle ear disorders, laryngopharyngeal reflux has been identified as a contributing or causative factor. One possible mode by which laryngopharyngeal reflux may contribute is by seeding of the extragastric mucosa with H. pylori. The clinical significance of the discovery of H. pylori in extragastric tissues in the head and neck is unclear. There is no evidence of a pathologic or active role of H. pylori in otorhinolaryngological disorders. The suggestion that the sinonasal cavities and pharynx may serve as a reservoir for H. pylori and that reinfection of the stomach occurs after eradication therapy awaits further studies for confirmation. No connection was observed between H. pylori found in the stomach and H. pylori found in the head and neck. Also, these bacteria, found in the head and neck tissues, may be accidental or innocent bystanders that do not affect the pathways of otolaryngological and gastroduodenal diseases. This review examines the evidence for a possible relationship of H. pylori with otorhinolaryngological diseases.

Paired analysis of the microbiota between surface tissue swabs and biopsies from pediatric patients undergoing adenotonsillectomy

INTRODUCTION

Culture-independent methods, based on bacterial 16 S rRNA gene sequencing, have been used previously to investigate the adenotonsillar microbiota. However, these studies have focused on a single sampling site (usually a surface swab). We aimed to investigate potential differences in adenotonsillar microbiota according to sampling location, both on and within the adenoids and palatine tonsils.

METHODS

Pediatric patients (n = 28, mean age five years) undergoing adenotonsillectomy were recruited for this study. At the time of surgery, a mucosal adenoid surface swab and an adenoid tissue biopsy was collected. Immediately following surgery, the crypts of the right and left tonsils were swabbed, and a surface and core tissue sample from the right tonsil were also collected. Bacterial 16 S rRNA gene-targeted amplicon sequencing was used to determine the bacterial composition of the collected samples.

RESULTS

There was no significant difference in diversity or composition of the adenoid microbiota based on sampling site. However, the Shannon-Wiener and Inverse-Simpson diversity indices differed significantly (p < 0.05) between the microbial communities of the three different tonsil sampling sites. There was a higher average relative abundance of members from the genera Streptococcus, Actinobacillus, and Neisseria in the tonsil crypts when compared with surface and core tonsil tissue samples.

CONCLUSION

Our results indicate that there is variation in bacterial diversity and composition based on sampling sites in the tonsils but not the adenoids. The difference in microbiota between the surface and the tissue may have implications for our understanding of the pathogenesis of recurrent tonsillitis and have treatment implications.

Adenotonsillar microbiome: an update

Pathogenic bacteria associated with the adenoids and tonsils cause much morbidity in the paediatric population. Hyperplasia of the adenoids is associated with otitis media with effusion and hyperplasia of the palatine tonsils is associated with both recurrent tonsillitis and obstructive sleep apnoea. Most current knowledge of the microbiology of the upper airways has been derived from culture-based studies, which usually reflect only a small fraction of the bacteria present on the mucosal surface. Culture-independent molecular surveys based on 16S ribosomal RNA sequencing are now being employed to determine the microbiota on the surface and within the tissue of adenoids and palatine tonsils. This review describes the new techniques applied in determining the microbiome and summarises the results of studies employing these techniques.

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.

Adenoid hypertrophy and chronic rhinosinusitis: Helicobacter pylori on antral lavages, adenoid tissue and salival inmunoglobuline A on paediatric patients

OBJECTIVE

To determine Helicobacter pylori presence on antral lavages, adenoids and salival inmunoglobuline A on paediatric patients with chronic rhinosinusitis without nasal polyps (CRSsNP) and adenoid hypertrophy.

METHODS

Adenoid tissue, liquid obtained from antral lavages and saliva from 28 children diagnosed with CRSsNP, from the paediatric otorhinolaryngology practice of "Dr. Domingo Luciani" Hospital was taken and processed by means of polymerase chain reaction (PCR) using cagA, vacA and babA primers, also anatomopathological examination using Giemsa stain of the adenoids, determination of salivary specific secretory inmunoglobuline A (sIgA), socio-economic condition using the Graffar scale and associated gastrointestinal symptoms were assessed.

RESULTS

No evidence of Helicobacter pylori neither in antral lavages liquid nor adenoid tissue was found using PCR and Giemsa stain. sIgA was present in 28.6% of the subjects. The most frequently found symptoms were, diarrhea in 17.9%, distension and abdominal pain in 10.7%, 64.3% of the patients were in working (28.6%) and low middle (35.7%) classes.

CONCLUSIONS

Helicobacter pylori is not present neither in maxillary sinuses nor adenoid tissue of the evaluated patients, sIgA it is a non-invasive method for assessment of immunologic challenge with the bacteria, not the presence of acute or chronic infection.

Associations between peripheral vertigo and gastroesophageal reflux disease

We hypothesize that peripheral vertigo is associated with gastroesophageal reflux disease (GERD). Two mechanisms could be considered – gastric acids may directly irritate the respiratory mucosa and cause inflammation, or Helicobacter pylori (H. pylori) could be present and cause local infection. Reflux material (Hydrochloric acid (HCl) and pepsin) could get into the middle ear via Eustachian tube and affect osseous structures directly. Disturbance of ossicles could cause tinnitus, which is more common for peripheral vertigo. H. pylori could also get in the esophagus and in the upper respiratory tract via gastroesophageal reflux, and could cause tympanosclerosis and fixation of ossicles. In our study group, 120 of 153 (78.4%) patients had gastroesophageal reflux disease (GERD). Diagnostic tests of H. pylori (rapid urease test or blood antibody test) were performed for 96 of 120 (80%) patients with GERD and were found positive for 32 of 96 (33.3%) patients. Peripheral vertigo was present in 93 of 120 (77.6%) patients with GERD compared to 33 of 126 (26%) patients without GERD (χ(2)=9.016, p=0.003). H. pylori and peripheral vertigo coexisted in 26 of 126 patients (20.6%) (OR 1.36; 95% CI 0.49-3.74, p=0.55). Our study demonstrated statistically significant association between peripheral vertigo and GERD but not between peripheral vertigo and H. pylori. Further more extensive investigations are needed in order to explore our hypothesis.

Prevalence of the Helicobacter pylori in the tonsils and adenoids

Introduction

There is an ongoing debate about the existence and effects of Helicobacter pylori (Hp) in adenotonsillar tissue.

Objective

A clinical study was conducted to assess the existence of Hp in the adenoid and/or adenotonsillar tissues, which were surgically excised due to chronic adenotonsillitis.

Methods

Phosphoglucosamine mutase gene for the detection of Hp and cytotoxin-associated gene as virulence gene were examined in 84 adenotonsillar tissues obtained from 64 patients and patients’ serum by using polymerase chain reaction.

Results

Hp IgG was detected in 57 (89%) patients’ serum. A total of seven tissue samples from 64 patients (10.9%) were found positive for Hp DNA, of which five were adenoids and two were tonsil tissues. All polymerase chain reaction positive samples were also positive for the cytotoxin-associated gene, which is a virulence determinant for the organism.

Conclusion

This study suggests that children are exposed to Hp at an early age of their life in this province. Hp may have a role in the pathogenesis of chronic adenotonsillitis, especially in endemic areas.

Prevalence of H. Pylori in Tonsillar Tissue of Patients with Chronic Recurrent Tonsillitis Using Rapid Urease Test in a Tertiary Referral Hospital in Sub Saharan Africa

There has been conflicting results regarding the presence of H. pylori in tonsillar tissue. Our objective was to analyze for the presence of H. pylori in tonsillar tissue in patients undergoing tonsillectomy for chronic recurrent tonsillitis using rapid urease test in a Tertiary care academic medical center in a sub Saharan hospital. A prospective cross-sectional analysis of 39 consecutive cases of patients undergoing tonsillectomy secondary to chronic recurrent tonsilitis was done. Rapid urease test was conducted on each tonsillectomy tissue and results were determined using color change at specific time intervals within 24 h. Average age of the patients was 4.3 years. Among the 39 tonsillar tissues analysed using rapid urease test, H. pylori was present in 30.5 % of the samples. Colonisation by H. pylori of the palatine tonsils is a new frontier with conflicting results depending on the accuracy of the test method used and population studied. More studies need to be performed to ascertain the different rates of colonisation based on geographical regions.

Helicobacter pylori infection - recent developments in diagnosis

Considering the recommended indications for Helicobacter pylori (H. pylori) eradication therapy and the broad spectrum of available diagnostic methods, a reliable diagnosis is mandatory both before and after eradication therapy. Only highly accurate tests should be used in clinical practice, and the sensitivity and specificity of an adequate test should exceed 90%. The choice of tests should take into account clinical circumstances, the likelihood ratio of positive and negative tests, the cost-effectiveness of the testing strategy and the availability of the tests. This review concerns some of the most recent developments in diagnostic methods of H. pylori infection, namely the contribution of novel endoscopic evaluation methodologies for the diagnosis of H. pylori infection, such as magnifying endoscopy techniques and chromoendoscopy. In addition, the diagnostic contribution of histology and the urea breath test was explored recently in specific clinical settings and patient groups. Recent studies recommend enhancing the number of biopsy fragments for the rapid urease test. Bacterial culture from the gastric biopsy is the gold standard technique, and is recommended for antibiotic susceptibility test. Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available, while molecular methods have gained attention mostly for detecting antibiotic resistance.

An association between Helicobacter pylori and upper respiratory tract disease: Fact or fiction?

Helicobacter pylori (H. pylori) is a major cause of chronic gastritis and gastric ulcers and considerable evidence supports the notion that infection with this bacterium is also associated with gastric malignancy in addition to various other conditions including pulmonary, vascular and autoimmune disorders. Gastric juice infected with H. pylori might play an important role in upper respiratory tract infection. Although direct and/or indirect mechanisms might be involved in the association between H. pylori and upper respiratory tract diseases, the etiological role of H. pylori in upper respiratory tract disorders has not yet been fully elucidated. Although various studies over the past two decades have suggested a relationship between H. pylori and upper respiratory tract diseases, the findings are inconsistent. The present overview describes the outcomes of recent investigations into the impact of H. pylori on upper respiratory tract and adjacent lesions.

Prevalence of Helicobacter pylori in adenotonsillar hypertrophy in children

CONCLUSION

Our results encourage the notion that the pharynx could be an extragastric reservoir of Helicobacter pylori (HP). The study confirmed the presence of HP in adenotonsillar tissue in children. It could have importance in the pathophysiology of upper respiratory diseases. However, its precise role in these processes remains unclear and requires further studies.

OBJECTIVE

A prospective study was carried out to evaluate the presence of HP in tonsillar and adenoid tissue in children. The study focused on real-time PCR analyzing CagA and VacA genotypes of HP strains.

METHODS

A total of 37 consecutive pediatric patients with adenotonsillar hypertrophy indicated for surgery were observed in a prospective study. Adenoidectomy and/or tonsillectomy was performed in each patient; 49 specimens were taken, 32 from adenoids and 17 from tonsils. The presence of HP and its genotype were tested in all samples by real-time PCR analysis.

RESULTS

Of 49 samples analyzed, 48 were positive for the presence of HP (98%), so only 1 sample was negative. While the genotype VacAs1bm2 was definitely dominant in adenoid tissue, wider distribution was observed in tonsillar tissue. Cag(+) strains represented one-fifth of all samples (21%).

Oral immunization with recombinant Lactobacillus acidophilus expressing the adhesin Hp0410 of Helicobacter pylori induces mucosal and systemic immune responses

Helicobacter pylori infection is relatively common worldwide and is closely related to gastric mucosa-associated lymphoid tissue (MALT) lymphoma, chronic gastritis, and stomach ulcers. Therefore, a safe and effective method for preventing H. pylori infection is urgently needed. Given that developing an effective vaccine against H. pylori is one of the best alternatives, H. pylori adhesin Hp0410 was expressed in the food-grade bacterium Lactobacillus acidophilus. The recombinant live bacterial vaccine was then used to orally vaccinate mice, and the immunoprotective effects of Hp0410-producing strains were investigated. H. pylori colonization in the stomach of mice immunized with the recombinant L. acidophilus was significantly reduced, in comparison with that in control groups. Furthermore, mucosal secretory IgA antibodies were elicited in the mucosal tissue of mice immunized with the recombinant bacteria, and specific anti-Hp0410 IgG responses were also detected in mouse serum. There was a significant increase in the level of protection against gastric Helicobacter infection following a challenge with H. pylori Sydney strain 1 (SS1). Our results collectively indicate that adhesin Hp0410 is a promising candidate vaccine antigen, and recombinant L. acidophilus expressing Hp0410 is likely to constitute an effective, low-cost, live bacterial vaccine against H. pylori.

Helicobacter pylori CagA: From Pathogenic Mechanisms to Its Use as an Anti-Cancer Vaccine

Helicobacter pylori colonizes the gastric mucosa of more than 50% of the human population, causing chronic inflammation, which however is largely asymptomatic. Nevertheless, H. pylori-infected subjects can develop chronic gastritis, peptic ulcer, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Chronic exposure to the pathogen and its ability to induce epithelial to mesenchymal transition (EMT) through the injection of cytotoxin-associated gene A into gastric epithelial cells may be key triggers of carcinogenesis. By deregulating cell-cell and cell-matrix interactions as well as DNA methylation, histone modifications, expression of micro RNAs, and resistance to apoptosis, EMT can actively contribute to early stages of the cancer formation. Host response to the infection significantly contributes to disease development and the concomitance of particular genotypes of both pathogen and host may turn into the most severe outcomes. T regulatory cells (Treg) have been recently demonstrated to play an important role in H. pylori-related disease development and at the same time the Treg-induced tolerance has been proposed as a possible mechanism that leads to less severe disease. Efficacy of antibiotic therapies of H. pylori infection has significantly dropped. Unfortunately, no vaccine against H. pylori is currently licensed, and protective immunity mechanisms against H. pylori are only partially understood. In spite of promising results obtained in animal models of infection with a number of vaccine candidates, few clinical trials have been conducted so far and with no satisfactory outcomes. However, prophylactic vaccination may be the only means to efficiently prevent H. pylori-associated cancers.

Relationship between Helicobacter pylori Adenotonsillar Colonization and Frequency of Adenotonsillitis in Children

BACKGROUND

There are insufficient data in the literature on the presence of Helicobacter pylori in tonsil and adenoid tissue of patients with only airway obstruction. This study examined the presence of H. pylori in surgical cases with airway obstruction or recurrent infection.

AIMS

To investigate the relationship between H. pylori adenotonsillar colonisation and the frequency of adenotonsillitis and to compare paediatric and adult patients according to H. pylori tonsillar colonisation.

STUDY DESIGN

Prospective clinical trial.

METHODS

PATIENTS SCHEDULED FOR ADENOIDECTOMY OR TONSILLECTOMY WERE CLASSIFIED INTO THREE GROUPS BASED ON INDICATIONS: paediatric infection (n=29), paediatric obstruction (n=29) and adult infection (n=12). Tissue samples obtained from patients were examined for the presence of H. pylori by culture, rapid urease test and polymerase chain reaction.

RESULTS

Forty-nine tonsil tissues were examined. Positive results were found in two specimens with the rapid urease test (4.1%) and three with polymerase chain reaction examination (6.1%). Only three positive polymerase chain reaction results (5.8%) were identified in 52 adenoid tissue samples. There were no statistically significant differences in the presence of H. pylori between paediatric infection and obstruction groups or between paediatric infection and adult infection groups.

CONCLUSION

In our study, there was a low incidence of H. pylori colonisation in tonsil and adenoid tissues. Regarding H. pylori colonisation, there was no significant difference between paediatric infection and obstruction groups. Also, no significant difference was found between adult and paediatric cases.

Presence of different genotypes of Helicobacter pylori in patients with chronic tonsillitis and sleep apnoea syndrome

Helicobacter pylori, a well-known gastric pathogen, has been detected in the oral cavity and oropharynx in tonsillar tissue. In our study, the presence of H. pylori in the tonsillar tissue of patients with chronic tonsillitis and sleep apnoea syndrome (SAS) was investigated. The aim was to detect and genotype H. pylori for a collection of data supporting the possible role of H. pylori in the aetiology of chronic tonsillitis and SAS. Helicobacter pylori was detected by real-time polymerase chain reaction (rt-PCR). 89 patients, 60 with a diagnosis of chronic tonsillitis and 29 with SAS, were tested. In the chronic tonsillitis group, Helicobacter was detected in 48 (80 %) specimens, cagA gene was detected in 12 samples (25 %) and 12 samples were negative. In SAS group, Helicobacter was found in 24 samples (82.76 %), cagA gene was detected in 5 (20.83 %) and 5 samples (17.24 %) were negative. Helicobacter pylori-specific immunoglobulins were tested by ELISA in the serum of 57 patients only with 41 (71.93 %) showing positive. Our results on H. pylori DNA detection and H. pylori seropositivity show 26.32 % discrepancy, slightly in favour of rt-PCR (15.79 % compared to 10.53 %). The H. pylori presence in tonsillar tissue does not depend on the type of oropharyngeal disease (p = 0.756). This study shows that oropharynx constitutes an extragastric reservoir of H. pylori infection which could serve as an aetiopathogenetic factor for chronic tonsillitis and tonsillar hyperplasia by SAS. No conclusion has yet been drawn about the mechanism of the process.

Genipin-cross-linked fucose-chitosan/heparin nanoparticles for the eradication of Helicobacter pylori

Helicobacter pylori is a significant human pathogen that recognizes specific carbohydrate receptors, such as the fucose receptor, and produces the vacuolating cytotoxin, which induces inflammatory responses and modulates the cell-cell junction integrity of the gastric epithelium. The clinical applicability of topical antimicrobial agents was needed to complete the eradication of H. pylori in the infected fundal area. In the present study, we combined fucose-conjugated chitosan and genipin-cross-linking technologies in preparing multifunctional genipin-cross-linked fucose-chitosan/heparin nanoparticles to encapsulate amoxicillin of targeting and directly make contact with the region of microorganism on the gastric epithelium. The results show that the nanoparticles effectively reduced drug release at gastric acids and then released amoxicillin in an H. pylori survival situation to inhibit H. pylori growth and reduce disruption of the cell-cell junction protein in areas of H. pylori infection. Furthermore, with amoxicillin-loaded nanoparticles, a more complete H. pylori clearance effect was observed, and H. pylori-associated gastric inflammation in an infected animal model was effectively reduced.

Epidemiology of Helicobacter pylori infection and public health implications

This review summarizes studies on the epidemiology and public health implications of Helicobacter pylori published in peer-reviewed journals from April 2010 through March 2011. Prevalence rates vary widely between different geographical regions and ethnic groups. An interesting study from the USA identified the degree of African ancestry as an independent predictor of H. pylori infection. Two studies have demonstrated early childhood as the period of transmission of infection and identified an infected sibling as an important risk factor. An oral-oral route of spread has been substantiated with several studies showing the presence of H. pylori in the oral cavity. Studies have shown the presence of H. pylori in drinking water and the role of poor living conditions and sanitation in H. pylori infection, supporting an oral-fecal route of spread. Screening for H. pylori as a gastric cancer pre-screening strategy has been described in Japan, and the importance of H. pylori eradication as a gastric cancer-prevention strategy has now been further emphasized in Japanese guidelines. Two studies have shown a decrease in the burden of dyspepsia and peptic ulcer disease with H. pylori eradication.

Epidemiology of Helicobacter pylori infection and public health implications

This review summarizes studies on the epidemiology and public health implications of Helicobacter pylori published in peer-reviewed journals from April 2010 through March 2011. Prevalence rates vary widely between different geographical regions and ethnic groups. An interesting study from the USA identified the degree of African ancestry as an independent predictor of H. pylori infection. Two studies have demonstrated early childhood as the period of transmission of infection and identified an infected sibling as an important risk factor. An oral-oral route of spread has been substantiated with several studies showing the presence of H. pylori in the oral cavity. Studies have shown the presence of H. pylori in drinking water and the role of poor living conditions and sanitation in H. pylori infection, supporting an oral-fecal route of spread. Screening for H. pylori as a gastric cancer pre-screening strategy has been described in Japan, and the importance of H. pylori eradication as a gastric cancer-prevention strategy has now been further emphasized in Japanese guidelines. Two studies have shown a decrease in the burden of dyspepsia and peptic ulcer disease with H. pylori eradication.