Association Between Helicobacter pylori Exposure and Decreased Odds of Eosinophilic Esophagitis-A Systematic Review and Meta-analysis

Epidemiologic and Clinical Clues to the Etiology of Eosinophilic Esophagitis

Despite the rising prevalence and incidence of eosinophilic esophagitis (EoE), the etiology and pathophysiology remain unknown. Studies to date suggest that complex interactions between genetic and environmental risk factors result in the development and presentation of disease. Examining environmental factors both in the early life and later life exposures offers potential clues for the development of EoE, although challenges exist in making causal inferences due to diagnostic delay and access, ascertainment biases, and misclassification of cases. The authors review studies supporting early life factors as etiologic factors in the development of EoE.

Helicobacter pylori and oral-gut microbiome: clinical implications

More than half of the world's population are colonized with H. pylori; however, the prevalence varies geographically with the highest incidence in Africa. H. pylori is probably a commensal organism that has been associated with the development of gastritis, ulcers, and gastric cancer. H. pylori alone is most probably not enough for the development of gastric carcinoma, but evidence for its association with the disease is high and has, therefore, been classified by the International Agency for Research on Cancer as a Class 1 carcinogen. Bacteroidetes and Fusobacteria positively coexisted during H. pylori infection along the oral-gut axis. The eradication therapy required to treat H. pylori infection can also have detrimental consequences for the gut microbiota, leading to a decreased alpha diversity. Therefore, therapy regimens integrated with probiotics may abolish the negative effects of antibiotic therapy on the gut microbiota. These eradication therapies combined with probiotics have also higher rates of eradication, when compared to standard treatments, and are associated with reduced side effects, improving the patient's compliance. The eradication therapy not only affects gut microbiome but also affects the oral microbiome with robust predominance of harmful bacteria. However, there have been reports of a protective role of H. pylori in Barrett's esophagus, esophageal adenocarcinoma, eosinophilic esophagitis, IBD, asthma, and even multiple sclerosis. Therefore, eradication therapy should be carefully considered, and test to treat policy should be tailored to specific communities especially in highly endemic areas. Supplementation of probiotics, prebiotics, herbals, and microbial metabolites to reduce the negative effects of eradication therapy should be considered. After failure of many eradication attempts, the benefits of H. pylori eradication should be carefully balanced against the risk of adverse effects especially in the elderly, persons with frailty, and intolerance to antibiotics.

Review article: Emerging insights into the epidemiology, pathophysiology, diagnostic and therapeutic aspects of eosinophilic oesophagitis and other eosinophilic gastrointestinal diseases

BACKGROUND

Eosinophilic gastrointestinal diseases (EGIDs) are chronic, immune-mediated disorders characterised clinically by gastrointestinal symptoms and histologically by a pathologic increase in eosinophil-predominant inflammation in the gastrointestinal tract, in the absence of secondary causes of eosinophilia.

AIMS

To highlight emerging insights and research efforts into the epidemiology, pathophysiology, diagnostic and therapeutic aspects of eosinophilic oesophagitis (EoE) and non-EoE EGIDs, and discuss key remaining knowledge gaps.

METHODS

We selected and reviewed original research, retrospective studies, case series, randomised controlled trials, and meta-analyses.

RESULTS

Standardised nomenclature classifies EGIDs as EoE, eosinophilic gastritis (EoG), eosinophilic enteritis (EoN), and eosinophilic colitis (EoC). Incidence and prevalence of EoE are rising, emphasising the need to better understand how environmental risk factors and genetic features interact. Advances in understanding EoE pathophysiology have led to clinical trials of targeted therapy and the approval (in the United States) of dupilumab for EoE. Several therapies that are under investigation hope to satisfy both histologic and clinical targets. For non-EoE EGIDs, efforts are focused on better defining clinical and histopathologic disease determinants and natural history, as well as establishing new therapies.

CONCLUSIONS

Unmet needs for research are dramatically different for EoE and non-EoE EGIDs. In EoE, non-invasive diagnostic tests, clinicopathologic models that determine the risk of disease progression and therapeutic failure, and novel biologic therapies are emerging. In contrast, in non-EoE EGIDs, epidemiologic trends, diagnostic histopathologic thresholds, and natural history models are still developing for these more rare disorders.

Helicobacter pylori infection is associated with decreased odds for eosinophilic esophagitis in Mexican patients

BACKGROUND

The incidence of eosinophilic esophagitis (EoE) is increasing in some regions of the world. Retrospective studies have found an inverse association with Helicobacter pylori infection (H. pylori). A recent prospective study has questioned this relationship. We aimed to evaluate this relationship in Mexican patients.

PATIENTS AND METHODS

We evaluated adult patients without prior eradication of H. pylori. Cases were defined by the presence of esophageal symptoms and >15 eosinophils/high power field (HPF) in the esophageal biopsy. Controls were defined by the presence of <15 eosinophils/HPF in esophageal biopsy. H. pylori infection was defined by histology. Patients were matched by age and gender assigning four controls per case.

RESULTS

We included 190 patients: 38 cases and 152 controls. Cases had higher frequency of atopy, dysphagia, food impaction, peripheral eosinophilia, and endoscopic EoE abnormalities. The overall prevalence of H. pylori was 63.6%. Cases had significantly lower prevalence of H. pylori than controls (36.8% vs. 70.4%, OR 0.21 95% CI 0.08-0.69, p = 0.001). Atopic patients had lower prevalence of H. pylori than non-atopic: 13.1% vs. 50.5% (OR 0.20, 95% CI 0.06-0.69, p < 0.001), particularly allergic rhinitis and food allergy.

CONCLUSIONS

We observed an inverse relationship between H. pylori and EoE as well as atopy. Studies in experimental models of EoE that clarify the role of H. pylori in this interaction are required, as well as robust studies that include other factors (socioeconomic, cultural, microbiota, etc.) in order to clarify this relationship.

Update on the association between Helicobacter pylori infection and asthma in terms of microbiota and immunity

H. pylori is a gram-negative bacterium that is usually acquired in childhood and can persistently colonize the gastric mucosa of humans, affecting approximately half of the world's population. In recent years, the prevalence of H. pylori infection has steadily reduced while the risk of allergic diseases has steadily climbed. As a result, epidemiological research indicates a strong negative association between the two. Moreover, numerous experimental studies have demonstrated that eradicating H. pylori increases the risk of allergic diseases. Hence, it is hypothesized that H. pylori infection may act as a safeguard against allergic diseases. The hygiene hypothesis, alterations in gut microbiota, the development of tolerogenic dendritic cells, and helper T cells could all be involved in H. pylori's ability to protect against asthma. Furthermore, Studies on mice models have indicated that H. pylori and its extracts are crucial in the management of asthma. We reviewed the in-depth studies on the most recent developments in the relationship between H. pylori infection and allergic diseases, and we discussed potential mechanisms of the infection's protective effect on asthma in terms of microbiota and immunity. We also investigated the prospect of the application of H. pylori and its related components in asthma, so as to provide a new perspective for the prevention or treatment of allergic diseases.

Global Incidence and Prevalence of Eosinophilic Esophagitis, 1976-2022: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

Owing to 2018 expanded diagnostic criteria for eosinophilic esophagitis (EoE) and thus a possible increase in diagnosis, previous studies on the global incidence and prevalence of EoE may need to be updated. We aimed to describe global, regional, and national trends in the incidence and prevalence of EoE from 1976 to 2022 and analyze their associations with geographic, demographic, and social factors through a systematic review.

METHODS

We searched the PubMed/MEDLINE, Embase, CINAHL, Google Scholar, and Cochrane databases from their inception dates to December 20, 2022, for studies that reported the incidence or prevalence of EoE in the general population. We calculated the global incidence and prevalence of EoE using pooled estimates with 95% confidence intervals (CIs) and performed subgroup analysis based on age, sex, race, geographical area, World Bank income group, and diagnostic criteria of EoE.

RESULTS

Forty studies met the eligibility criteria, including over 288 million participants and 147,668 patients with EoE from 15 countries across the five continents. The global pooled incidence and prevalence of EoE were 5.31 cases per 100,000 inhabitant-years (95% CI, 3.98-6.63; number of studies, 27; sample population, 42,191,506) and 40.04 cases per 100,000 inhabitant-years (95% CI, 31.10-48.98; number of studies, 20; sample population, 30,467,177), respectively. The pooled incidence of EoE was higher in high-income countries (vs low- or middle-income countries), males, and North America (vs Europe and Asia). The global prevalence of EoE followed a similar pattern. The pooled prevalence of EoE gradually increased from 1976 to 2022 (1976-2001; 8.18; 95% CI, 3.67-12.69 vs 2017-2022; 74.42; 95% CI, 39.66-109.19 cases per 100,000 inhabitant-years).

CONCLUSIONS

The incidence and prevalence of EoE have increased substantially and vary widely across the world. Further research is needed to evaluate the incidence and prevalence of EoE in Asia, South America, and Africa.

Forty years of Helicobacter pylori infection and changes in findings at esophagogastroduodenoscopy

BACKGROUND

It is 40 years since the discovery of Helicobacter pylori infection. Over that time major changes have occurred in esophagogastroduodenoscopy (EGD) findings. The aim of this review is to describe these changes, and the important role H. pylori infection has played in their evolution.

METHODS

References were identified through searches of PubMed using the search terms-endoscopy time trends, peptic ulcer disease, gastroesophageal reflux disease, upper gastrointestinal cancer, gastric polyps, H. pylori, eosinophilic gastrointestinal disorders, and celiac disease, from 1970 through December 2021.

RESULTS

The prevalence of H. pylori infection has fallen and consequently, H. pylori-positive peptic ulcer disease has become rare. Gastroesophageal reflux disease is now the commonest disorder diagnosed at EGD, and Barrett's esophagus has increased in parallel. Cancer of the distal stomach has fallen while esophageal adenocarcinoma and reflux-related cardia cancer have risen. Gastric polyps have changed from hyperplastic and adenomas to sporadic fundic gland polyps. Antimicrobial resistance has made H. pylori infection more difficult to eradicate. Eosinophilic gastrointestinal disorders, particularly eosinophilic esophagitis, have emerged as important new allergic disorders. Celiac disease has changed and increased.

CONCLUSIONS

EGD findings appear to have changed from features suggesting a H. pylori-positive "phenotype" 40 years ago to a H. pylori-negative "phenotype" today. These changes have major implications for the management of gastrointestinal disorders.

Helicobacter pylori Found Incidentally During Upper Endoscopy Performed for Diagnosis of Common Pediatric Gastrointestinal Diseases

BACKGROUND

Helicobacter pylori ( H. pylori ) gastritis may be an incidental finding during upper endoscopy performed to diagnose celiac disease (CeD), inflammatory bowel disease (IBD) and eosinophilic esophagitis (EoE). We aimed to describe the incidence of H. pylori in children undergoing endoscopy for CeD, IBD and EoE and determine the indications for treatment.

METHODS

A retrospective, single-center study based on the review of endoscopy reports of pediatric patients, diagnosed with CeD, IBD and EoE, between January 2017 and December 2021. Data collected included; age, gender, hematologic parameters, endoscopic, histologic and H. pylori culture results, and information on eradication treatment.

RESULTS

H. pylori gastritis was diagnosed in 120 of 558 (21.5%) children [72 (60%) female, mean age 10.6 years] during gastroscopy performed for the diagnosis of other GI diseases. H. pylori was present in 87 of 404 (21.5%) CeD, 27 of 113 (23.9%) IBD and 6 of 41 (14.6%) EOE patients ( P = 0.46). The main indication for treatment was the presence of ulcers, in 4 of 120 (3.3%), and erosions in 17 of 120 (14.2%). Eradication treatment was recommended in 22 of 120 (18.3%) patients, 8 of 87 (9.2%) CeD, 10 of 27 (37%) IBD and 4 of 6 (66.7%) EoE patients, P < 0.001. Four independent positive treatment predictors were identified; age above 10 years {odds ratio (OR) = 10.57 [95% confidence interval (CI) 1.88-59.36], P = 0.007} the presence of nodular gastritis (OR = 5.03 [95% CI 1.09-23.15], P = 0.38), erosions [OR = 49.21 (95% CI 8.19-295.83), P < 0.000] and ulcers [OR = 22.69 (95% CI 1.25-410.22), P = 0.035]. CeD was a strong negative predictor for treatment [OR = 0.23 (95% CI 0.002-0.241), P = 0.002].

CONCLUSIONS

H. pylori gastritis is a common incidental finding during endoscopy. The indications for treatment are not well defined and should be further investigated.

The association between Helicobacter pylori infection and inflammatory bowel disease in children: A systematic review with meta-analysis

BACKGROUND

Available literature has reported the association of Helicobacter pylori (H pylori) infection with inflammatory bowel disease (IBD) in adults. However, only a few studies have addressed the disease in children.

AIM

To ascertain the correlation of H pylori infection with IBD among children.

METHODS

The aim of this systematic review and meta-analysis is to assess the association between H pylori infection and IBD in children. We searched databases including Cochrane, EMBASE, Google Scholar, PubMed, Medline, and Web of Science to select relevant studies. Ultimately, based on predetermined inclusion criteria, we included 6 studies that met the requirements. Review Manager and Stata software were used to extract and analyze the data from the relevant studies. In the methods, we employed both qualitative and quantitative approaches for comprehensive analysis. Qualitative analysis involved describing study designs, sample characteristics, and results, while quantitative analysis involved statistical tests such as calculating pooled risk ratios and 95% confidence intervals to evaluate the association between H pylori infection and IBD in children. Lastly, by combining the results of the individual studies, our objective is to provide a comprehensive understanding of the relationship between H pylori infection and IBD in children.

RESULTS

In totality, we involved 2236 participants that were recruited in 6 studies. We detected no significant difference in H pylori prevalence (9.8% vs 12.7%, P = .12) by comparing the children IBD group to controls. Among the IBD children, we estimated odds ratio (OR) of H pylori infection to 0.62 [(95% confidence interval (CI) of 0.34-1.12)]. In children suffering from ulcerative colitis (UC) and Crohn disease (CD), the H pylori infection rates were higher than in those with IBD-unclassified (IBDU).When analyzed stratified by disease of study design, In CD group [OR = 1.42, 95% CI: 0.72-2.80)] (I2 = 0%, P = .64). but no significant difference in CD group.

CONCLUSIONS

No correlation was found between H pylori infection and the occurrence of IBD in children.

Helicobacter pylori in children: think before you kill the bug!

Since the discovery of Helicobacter pylori (H. pylori) as the causative organism for gastric and duodenal ulcers four decades ago and subsequent recognition as class 1 gastric carcinogen, countless numbers of studies have been conducted and papers published, on the efficacy of various management strategies to eradicate the infection. In adults, a global consensus by the experts in the field concluded that H. pylori gastritis is an infectious disease and requires treatment irrespective of the presence or absence of symptoms due to the potential for serious complication like peptic ulcer disease and gastric neoplasia. However, although more than half the world's population harbors H. pylori, these serious complications occur only in a small minority of the infected population, even less so in childhood. More importantly, there is accumulating evidence for beneficial role of H. pylori against many chronic health conditions, from several epidemiological and laboratory studies. No doubt, eradication therapy is indicated in children with H. pylori-related peptic ulcer disease. Even though the pediatric guidelines from various learned societies recommend against a "test and treat" strategy, this is not always adhered to. With the accumulating evidence of the possible beneficial role of H. pylori, it is time to pause and think, are we causing more harm than good by eradicating H. pylori in every child who has this bug?

Barrett's Esophagus in Eosinophilic Esophagitis in Swiss Eosinophilic Esophagitis Cohort Study (SEECS)

INTRODUCTION

There is a complex interrelationship between gastroesophageal reflux disease (GERD) and eosinophilic esophagitis (EoE) potentially promoting the occurrence and modulating severity of each other reciprocally. Presence of Barrett's esophagus (BE) is a defining factor for the diagnosis of GERD. While several studies investigated the potential impact of concomitant GERD on the presentation and course of EoE, little was known with regards to BE in EoE patients.

METHODS

We analyzed prospectively collected clinical, endoscopic, and histological data from patients enrolled in the Swiss Eosinophilic Esophagitis Cohort Study (SEECS) regarding differences between EoE patients with (EoE/BE+) versus without BE (EoE/BE-) and determined the prevalence of BE in EoE patients.

RESULTS

Among a total of 509 EoE patients included in our analysis, 24 (4.7%) had concomitant BE with a high male preponderance (EoE/BE+ 83.3% vs. EoE/BE- 74.4%). While there were no differences in dysphagia, odynophagia was significantly (12.5 vs. 3.1%, p = 0.047) more common in EoE/BE+ versus EoE/BE-. General well-being at last follow-up was significantly lower in EoE/BE+. Endoscopically, we observed an increased incidence of fixed rings in the proximal esophagus in EoE/BE+ (70.8 vs. 46.3% in EoE/BE-, p = 0.019) and a higher fraction of patients with a severe fibrosis in the proximal histological specimen (8.7 vs. 1.6% in EoE/BE, p = 0.017).

CONCLUSION

Our study reveals that BE is twice as frequent in EoE patients compared to general population. Despite many similarities between EoE patients with and without BE, the finding of a more pronounced remodeling in EoE patients with Barrett is noteworthy.

Eosinophilic Esophagitis—What Do We Know So Far?

Eosinophilic esophagitis is a Th-2 antigen-mediated disease in which there is an influx of eosinophils to all layers of the esophagus, triggering an inflammatory response. Chronic inflammatory process causes esophageal remodeling, leading to difficulties in swallowing. Food impaction, heartburn, and chest pain are other characteristic (but not pathognomonic) symptoms in adults. Although the disease has only been described since in the early 1970s, its incidence and prevalence are rapidly growing, especially in Western countries. According to the diagnostic guidelines, there should be at least 15 eosinophils visible per high-power field in biopsies obtained from different sites in the esophagus upon endoscopy with relevant esophageal symptoms. Other diseases that can cause esophageal eosinophilia should be ruled out. Eosinophilic esophagitis treatment may be challenging; however, new methods of management have recently emerged. The currently used proton pump inhibitors, topical corticosteroids, and elimination diet are combined with biological treatment. New methods for disease diagnostics and clinical course assessment are also available. This review presents current knowledge about the disease, supported by the latest research data.

Discussion on the common controversies of Helicobacter pylori infection

BACKGROUND

Helicobacter pylori ( H. pylori ) can persistently colonize on the gastric mucosa after infection and cause gastritis, atrophy, metaplasia, and even gastric cancer (GC).

METHODS

Therefore, the detection and eradication of H. pylori are the prerequisite.

RESULTS

Clinically, there are some controversial issues, such as why H. pylori infection is persistent, why it translocases along with the lesser curvature of the stomach, why there is oxyntic antralization, what the immunological characteristic of gastric chronic inflammation caused by H. pylori is, whether H. pylori infection is associated with extra-gastric diseases, whether chronic atrophic gastritis (CAG) is reversible, and what the potential problems are after H. pylori eradication. What are the possible answers?

CONCLUSION

In the review, we will discuss these issues from the attachment to eradication in detail.

Breastfeeding Is Associated with Lower Likelihood of Helicobacter Pylori Colonization in Babies, Based on a Prospective USA Maternal-Infant Cohort

BACKGROUND

Mother-to-child transmission of Helicobacter pylori (H. pylori) is the primary source of intrafamilial spread in early childhood in regions of high H. pylori prevalence. However, early-in-life H. pylori colonization and associated protective or risk factors have not been fully evaluated in lower prevalence regions, such as the USA.

AIMS

Therefore, from a well-characterized prospective US cohort, we selected women who provided fecal samples during pregnancy and had paired fecal samples from their babies up to 24 months postpartum. We evaluated maternal and baby factors associated with likelihood of H. pylori colonization in the babies. Fecal antigen testing was used to determine H. pylori status. We also evaluated the association between maternal breastmilk cytokines and H. pylori colonization in breastfed babies.

RESULTS

Among included mother-baby pairs (n = 66), H. pylori prevalence was 31.8% in mothers and 19.7% in their babies. Dominant breastfeeding (adjusted odds ratio [aOR] 0.17, 95% CI 0.03-0.98) and maternal IBD (aOR 0.05, 95% CI 0.01-0.27) were associated with significantly lower likelihood of H. pylori colonization among babies; no other clinical factors were associated with H. pylori colonization in the babies. Matrix metalloproteinase-10 (MMP-10) and tumor necrosis factor-related activation-induced cytokine expression were significantly higher in breastmilk of mothers with H. pylori positive vs negative babies.

CONCLUSIONS

Consistent with data from high H. pylori prevalence regions, our findings suggest dominant breastfeeding may protect against early H. pylori colonization. Downregulation of pro-inflammatory cytokines such as MMP-10 may be relevant in mediating this protection among breastfed babies, but more data are needed.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for 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 various clinical fields.

Low Prevalence of Extraesophageal Gastrointestinal Pathology in Patients with Eosinophilic Esophagitis

BACKGROUND

Limited data are available to support current guidelines recommendations on obtaining gastric and duodenal biopsies of patients with clinical and histologic manifestations consistent with eosinophilic esophagitis (EoE) to rule out eosinophilic gastritis (EG) or duodenitis (EoD). Our study examined the prevalence of concomitant extraesophageal, gastrointestinal pathology to better characterize the diagnostic yield of additional biopsies.

METHODS

This was a single-center, retrospective study which utilized ICD 9 codes (530.13) and search queries of pathology reports ("Eosinophilic esophagitis," "EoE") to identify EoE patients. Patient endoscopy reports, pathology reports, and office notes were manually reviewed to characterize cases.

RESULTS

The electronic health record search yielded 1,688 EoE adults. In those who had extra-esophageal biopsies obtained, EG was identified in 34 (3.4%), H. pylori in 45 (4.6%), EoD in 27 (3.3%), and histology consistent with celiac disease in 20 (2.5%). Endoscopic abnormalities were found in the stomach of 92% of patients with EoE and EG and in the duodenum of 50% of patients with EoE and EoD. Symptoms of dyspepsia and/or abdominal pain occurred in a significantly greater proportion of patients with extraesophageal disease (64% vs. 19% in EoE group, p < 0.001). Overall, extraesophageal pathology would have been missed in 1.4% of patients lacking either symptoms or endoscopic signs suggestive of extraesophageal disease.

CONCLUSIONS

The yield of gastric and duodenal biopsies in adults with EoE is low, with 6.5% of patients demonstrating histologic features of celiac disease, Helicobacter pylori, EG, and/or EoD. Biopsies of extraesophageal, gastrointestinal sites in patients with suspected or previously diagnosed EoE should consider symptom and endoscopy manifestations as well as the potential impact of histopathologic findings on clinical management.

[Diagnosis and Treatment of Eosinophilic Esophagitis]

Eosinophilic esophagitis (EoE) is a chronic, immune/antigen-mediated esophageal disease characterized by symptoms of esophageal dysfunction and eosinophil-predominant inflammation. The diagnostic criteria for EoE have changed with our growing knowledge over the past two decades. Esophageal eosinophilia, which responds histologically to a proton pump inhibitor (PPI) is not a distinct disease but a subset of EoE. An endoscopic scoring system that relies on the assessment of exudates, rings, edema, furrows, and strictures is a useful tool for assessing endoscopic severity. PPIs are regarded as safe and effective first-line treatments for EoE. Oral topical corticosteroids or dietary therapy are also options for first-line treatment. Endoscopic dilation is effective for relieving the dysphagia symptoms of a patient with an esophageal stricture.

Type 2 Inflammation in Eosinophilic Esophagitis: From Pathophysiology to Therapeutic Targets

Eosinophilic esophagitis (EoE) is a chronic immune-mediated disease of the esophagus characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation, whose incidence is rising. It significantly affects patients’ quality of life and, if left untreated, results in fibrotic complications. Although broad consensus has been achieved on first-line therapy, a subset of patients remains non-responder to standard therapy. The pathogenesis of EoE is multifactorial and results from the complex, still mostly undefined, interaction between genetics and intrinsic factors, environment, and antigenic stimuli. A deep understanding of the pathophysiology of this disease is pivotal for the development of new therapies. This review provides a comprehensive description of the pathophysiology of EoE, starting from major pathogenic mechanisms (genetics, type 2 inflammation, epithelial barrier dysfunction, gastroesophageal reflux, allergens, infections and microbiota) and subsequently focusing on the single protagonists of type 2 inflammation (involved cells, cytokines, soluble effectors, surface proteins and transcription factors) that could represent present and future therapeutic targets, while summarizing previous therapeutic approaches in literature.

Epidemiology of Helicobacter pylori

In many countries alike, the time trends of gastric cancer, gastric and duodenal ulcer, ulcerative colitis, Crohn's disease, and colorectal cancer are characterized by similar birth-cohort patterns. Mortality from these diagnoses rose in cohorts born during the 19th century and then fell in subsequent cohorts born during the 20th century.

Immunogenetic, Molecular and Microbiotic Determinants of Eosinophilic Esophagitis and Clinical Practice-A New Perspective of an Old Disease

Eosinophilic oesophagitis (EoE) is a chronic, allergic disease associated with a T-lymphocyte response inducing esophageal eosinophilic infiltration in the esophagus. Inflammation and tissue fibrosis are responsible for the main clinical symptoms such as food impaction and dysphagia. The etiopathogenesis is multifactorial in which genetic and environmental factors coexist. The most common trigger is a non-IgE-mediated food allergy to milk, wheat, egg, soybean, nuts, fish, and seafood. The second factor we focus on is the contribution of genetic variation to the risk of EoE, describing the expression profile of selected genes associated with eosinophilic oesophagitis. We raise the topic of treatment, aiming to eliminate inflammation through an elimination diet and/or use of pharmacologic therapy with the use of proton pump inhibitors or steroids and endoscopic procedures to dilate the esophagus. We demonstrate that early diagnosis and effective treatment prevent the development of food impaction and decreased quality of life. The increasing presence of EoE requires bigger awareness among medical specialists concerning clinical features, the course of EoE, diagnostic tools, and management strategies.

Clinical Characteristics and Treatment Outcomes of Patients with Eosinophilic Esophagitis and Eosinophilic Gastroenteritis

BACKGROUND

Eosinophilic esophagitis (EoE) and eosinophilic gastroenteritis (EGE), part of the spectrum of eosinophilic gastrointestinal disorders (EGID), share pathogenic similarities. We examined differences regarding clinical characteristics and treatment outcomes between EoE and EGE cases.

METHODS

Two-hundred fifteen EGID patients, including 181 with EoE and 34 with EGE, diagnosed at Shimane University Hospital between February 2011 and March 2019 were enrolled. Information regarding clinical parameters and treatment outcomes was reviewed.

RESULTS

EoE showed significant male predominance (82.3%) as compared with EGE (50.0%) (p < 0.001). Furthermore, patients with EoE were significantly older and had a higher body mass index (24.8 ± 4.0 vs. 22.2 ± 4.3, p < 0.05). Over 90% of the EoE patients were initially given proton pump inhibitor (PPI) treatment, of whom 73.2% showed clinical and histological remission. Vonoprazan, a more potent acid inhibitor than PPI, was effective in two-thirds of the nonresponsive EoE patients initially treated with a PPI. In contrast, oral glucocorticoid administration was mainly given to patients with EGE (58.8%). Of 13 EGE patients treated with a food-elimination diet, responsible foods were successfully identified in 9, with 7 controlled in a state of remission without glucocorticoid therapy.

CONCLUSIONS

We found different clinical characteristics and treatment strategies in the present EoE and EGE cases. Most of the EoE patients responded to and were maintained by acid suppressive therapy, using PPI or vonoprazan. For EGE patients, glucocorticoid administration was mainly used though food-elimination diet therapy also showed beneficial effects.

Eosinophils and Bacteria, the Beginning of a Story

Eosinophils are granulocytes primarily associated with TH2 responses to parasites or immune hyper-reactive states, such as asthma, allergies, or eosinophilic esophagitis. However, it does not make sense from an evolutionary standpoint to maintain a cell type that is only specific for parasitic infections and that otherwise is somehow harmful to the host. In recent years, there has been a shift in the perception of these cells. Eosinophils have recently been recognized as regulators of immune homeostasis and suppressors of over-reactive pro-inflammatory responses by secreting specific molecules that dampen the immune response. Their role during parasitic infections has been well investigated, and their versatility during immune responses to helminths includes antigen presentation as well as modulation of T cell responses. Although it is known that eosinophils can present antigens during viral infections, there are still many mechanistic aspects of the involvement of eosinophils during viral infections that remain to be elucidated. However, are eosinophils able to respond to bacterial infections? Recent literature indicates that Helicobacter pylori triggers TH2 responses mediated by eosinophils; this promotes anti-inflammatory responses that might be involved in the long-term persistent infection caused by this pathogen. Apparently and on the contrary, in the respiratory tract, eosinophils promote TH17 pro-inflammatory responses during Bordetella bronchiseptica infection, and they are, in fact, critical for early clearance of bacteria from the respiratory tract. However, eosinophils are also intertwined with microbiota, and up to now, it is not clear if microbiota regulates eosinophils or vice versa, or how this connection influences immune responses. In this review, we highlight the current knowledge of eosinophils as regulators of pro and anti-inflammatory responses in the context of both infection and naïve conditions. We propose questions and future directions that might open novel research avenues in the future.

Similarity and difference in the characteristics of eosinophilic esophagitis between Western countries and Japan

Over the past two decades, the incidence and prevalence of eosinophilic esophagitis (EoE) have risen rapidly, especially in Western countries, with cases in Japan also showing a gradual increase in recent years. However, similarities and differences regarding the characteristics of EoE between Western countries and Japan remain to be clearly elucidated. The current clinical guidelines for diagnosis include symptoms related to esophageal dysfunction and dense eosinophilic infiltration in the esophageal epithelium. Most affected patients in Japan are diagnosed incidentally during a medical health check-up and asymptomatic cases with typical endoscopic findings suggestive of EoE are frequently encountered. Clinical characteristics of EoE in Japanese are similar to those seen in Western populations. The predominant symptom is dysphagia, with food impaction extremely rare in Japanese cases. Linear furrows are the most frequently reported characteristic endoscopic finding, while an esophageal stricture or narrow caliber is rarely observed. Treatment strategies for EoE include drugs, dietary restrictions, and endoscopic dilation when the disease is advanced with stricture formation. Although single therapy using a proton-pump inhibitor has been shown to achieve symptomatic and histological response in the majority of patients in Japan, no prospective randomized control studies that evaluated drug or elimination diet therapy have been presented. Overall, EoE has similar clinical characteristics between Japanese and Western populations, while disease severity seems to be milder in Japan. Additional studies are necessary to determine genetic factors, natural history of the disease, and treatment efficacy of drugs and elimination diet as compared to Western populations.

Eosinophilic esophagitis-established facts and new horizons

Despite dramatic advances in our understanding of the pathogenesis and course of disease in the relatively short timeframe since the discovery and first description of eosinophilic esophagitis (EoE) less than three decades ago, many open questions remain to be elucidated. For instance, we will need to better characterize atypical clinical presentations of EoE and other forms of esophageal inflammatory conditions with often similar clinical presentations, nut fulfilling current diagnostic criteria for EoE and to determine their significance and interrelationship with genuine EoE. In addition, the interrelationship of EoE with other immune-mediated diseases remains to be clarified. Hopefully, a closer look at the role of environmental factors and their interaction with genetic susceptibility often in context of atopic predisposition may enable identifying the candidate substances/agents/allergens and potentially earlier (childhood) events to trigger the condition. It appears plausible to assume that in the end—comparable to current concepts in other immune-mediated chronic diseases, such as for instance inflammatory bowel disease or asthma bronchiale—we will not be rewarded with the identification of a “one-and-only” underlying pathogenetic trigger factor, with causal responsibility for the disease in each and every EoE patient. Rather, the relative contribution and importance of intrinsic susceptibility, i.e., patient-driven factors (genetics, aberrant immune response) and external trigger factors, such as food (or aero-) allergens as well as early childhood events (e.g., infection and exposure to antibiotics and other drugs) may substantially differ among given individuals with EoE. Accordingly, selection and treatment duration of medical therapy, success rates and extent of required restriction in dietary treatment, and the need for mechanical treatment to address strictures and stenosis require an individualized approach, tailored to each patient. With the advances of emerging treatment options, the importance of such an individualized and patient-centered assessment will increase even further.

MALT lymphoma and eosinophilic oesophagitis: incidental finding- review of possible factors influencing the aetiopathogenesis of eosinophilic oesophagitis

An 11-year-old boy with a history of atopy and allergic rhinitis under treatment with sublingual immunotherapy was referred following several episodes of food impaction. Diagnosis of eosinophilic oesophagitis, chronic gastritis and gastric mucosa-associated lymphoid tissue (MALT) lymphoma associated to Helicobacter pylori were confirmed. Results of the extension study were negative and the lymphoma was resolved with eradicating treatment for H. pylori No improvement was observed in the oesophagitis after the withdrawal of immunotherapy and treatment with high proton pump inhibitor doses or following the omission of several foods to which subclinical sensitisation was confirmed. Oesophagitis was finally resolved by removing cow's milk protein. After 10 years, neither eosinophilic oesophagitis nor MALT lymphoma was observed.Gastric MALT lymphoma associated to H. pylori is a rare disorder in children. Although coexisting H. pylori infection is common in patients with eosinophilic oesophagitis, the association of gastric MALT lymphoma with eosinophilic oesophagitis has not been reported before.

Eosinophilic Esophagitis and Microbiota: State of the Art

Eosinophilic esophagitis (EoE) is a chronic, food-triggered, immune-mediated disease of the oesophagus, clinically characterized by symptoms referred to oesophagal dysfunction, and histologically defined by an eosinophil productive inflammation of the oesophagal mucosa, among other cell types. The involvement of an adaptive Th2-type response to food antigens in EoE was known since 2000; several cytokines and chemokines promote food-specific responses, during which local production of IgE, but also IgG4 derived from plasma cells in lamina propria of oesophagal mucosa might play an important role. Evidence pointing towards a possible role for the innate immunity in EoE has arisen recently. Together, this evidence gives rise to a potential role that the innate immune system in general, and also the microbial pattern recognition receptors (PRRs) might play in EoE pathogenesis. Among PRRs, Toll-like receptors (TLRs) are type-I transmembrane receptors expressed both on epithelial and lamina propria cells with the capacity to distinguish between pathogen and commensal microbes. As TLRs in the different intestinal epithelia represent the primary mechanism of epithelial recognition of bacteria, this evidence underlines that oesophagal TLR-dependent signaling pathways in EoE support the potential implication of microbiota and the innate immune system in the pathogenesis of this disease. The oesophagal mucosa hosts a resident microbiota, although in a smaller population as compared with other districts of the gastrointestinal tract. Few studies have focused on the composition of the microbiota of the normal oesophagus alone. Still, additional information has come from studies investigating the oesophagal microbiota in disease and including healthy patients as controls. Our review aims to describe all the evidence on the oesophagal and intestinal microbiota in patients with EoE to identify the specific features of dysbiosis in this condition.

Extra-Gastric Manifestations of Helicobacter pylori Infection

Helicobacter Pylori (H. pylori) is a Gram-negative flagellated microorganism that has been extensively studied since its first isolation due to its widespread diffusion and association with numerous diseases. While the bacterium is proved to be a causative factor for a number of gastric diseases such as gastritis, gastric adenocarcinoma, and MALT-lymphoma, its role at other gastrointestinal levels and in other systems is being thoroughly studied. In this article, we reviewed the latest published clinical and laboratory studies that investigated associations of H. pylori with hematologic diseases such as Vitamin B12- and iron-deficiency anemia, primary immune thrombocytopenia, and with a number of dermatologic and ophthalmic diseases. In addition, the putative role of the bacterium in inflammatory bowel diseases, esophageal disorders, metabolic, diseases, neurologic diseases and allergy were outlined.

Epidemiology and risk factors for eosinophilic esophagitis: lessons for clinicians

INTRODUCTION

The rapid expansion in the epidemiology of eosinophilic esophagitis (EoE) is being documented, along with cumulative research assessing environmental exposures associated with EoE and susceptibility due to genetic variants.

AREAS COVERED

Incidence rates for EoE of 5-10 new cases per 100,000 inhabitants annually have shown an increase in recent reports of up to 20 in some countries; the highest prevalence being reported for Europe and North America, where EoE now affects more than 1 out of 1,000 people. EoE has been shown to be associated with several disorders, Th2-mediated atopies being the most common. Patients with EoE exhibit increased frequency of asthma, allergic rhinitis and eczema, and EoE has been considered as a late component of the atopic march. Risk variants in TSLP, CAPN14 and LRCC32 genes, among others, have all been related to EoE, and interact with prenatal and early life exposure potentially modifying abundance and composition of gut microbiome. Dysregulated interactions between bacteria and mucosal immunity emerge as leading causes of EoE.

EXPERT OPINION

The expanding epidemiology of EoE, the resources needed and subsequent increasing healthcare costs require additional effort to optimize cost-effective management and unveil mechanisms that enhance the development of future preventive strategies.

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.

Review - Helicobacter pylori and non-malignant upper gastro-intestinal diseases

This review takes into account recent publications focusing on the relationship between Helicobacter pylori infection and non-malignant diseases of the upper gastro-intestinal tract. The authors have summarized current knowledge on associations between the H pylori infection and non-malignant upper GI conditions including gastroesophageal reflux disease (GERD), Barrett's esophagus, eosinophilic esophagitis (EOE), peptic ulcer disease (PUD), H pylori gastritis, celiac disease and functional dyspepsia. In the field of GERD, current data focusing on different locations of H pylori infection detect significant differences between antrum- and corpus predominant gastritis explainable by different changes in acid secretion in different gastric niches. High volume studies from Sweden and Brazil underline the safety of H pylori eradication concerning the risk of Barret's esophagus or adenocarcinoma. The relationship betweenH pylori infection and EOE remains uncertain, but current data supports the concept of expected positive and protective effects of H pylori exposure reducing the risk of EOE. Analyzing biomarkers might be helpful to identify subjects under risk for the development of precancerous lesions after H pylori infection, where microRNAs, IL-9 and IL-4, and also Tc17/9 and Th17/9 and microbiota profiles showed promising results to identify subgroups under risk.

Review: Extragastric diseases and Helicobacter pylori

The involvement of Helicobacter pylori infection in many extra-gastroduodenal manifestations remains a fascinating field of investigation. However, for several of these supposed associations, the potential pathogenic mechanism remains unclear. The present review highlights the main associations of H pylori with extra-gastroduodenal manifestations reported during the last year. We searched for the most relevant studies on this topic, published between April 2019 and March 2020, identified using the term "Helicobacter" in the MEDLINE/Pubmed database. Consistent data emerged from studies investigating metabolic syndrome and ischaemic cardiovascular diseases. Other reported fields of investigation were hepatology, especially focused on non-alcoholic steatohepatitis, neurology, including Parkinson's disease and Alzheimer's disease, as well as dermatology. Inflammatory bowel disease (IBD), that comprises Crohn's disease and ulcerative colitis, may originate from a dysregulation of the host's immune response to commensal bacteria in individuals with genetic predisposition. The reduction of biodiversity and other specific imbalances in the faecal microbiome composition of IBD patients compared to that of healthy controls support this hypothesis. In this context, an inverse correlation between H pylori infection and IBD prevalence has been confirmed. Similar results were found in patients with kidney diseases and allergic manifestations. There are indications of the possible involvement of H pylori infection in metabolic syndrome and ischaemic cardiovascular diseases. However, due to a series of factors linked to study designs and the multifactorial pathogenesis of some diseases, further studies are needed.

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.

Systematic review: gastrointestinal infection and incident inflammatory bowel disease

BACKGROUND

The initiating events of chronic gastrointestinal (GI) inflammation in Crohn's disease (CD) and ulcerative colitis (UC) are not well-defined, but GI infections are implicated.

AIMS

To define the role of GI infections in risk of incident inflammatory bowel disease (IBD) and synthesise the current body of relevant translational data to provide biological context for associations between GI infections and IBD risk.

METHODS

We systematically reviewed electronic databases through February 2020. Clinical studies that provided risk estimates of the association between GI infections and incident IBD were included. Inclusion criteria were broader for translational studies aiming to define mechanisms of GI infections and predisposition to or protection from IBD.

RESULTS

Of the studies identified, 63 met full inclusion criteria. Among studies of clinical gastroenteritis, bacteria-specifically, Salmonella species, Campylobacter species and Clostridioides difficile-demonstrated consistent positive associations with risk of incident IBD. Of viruses, norovirus was associated with increased risk of incident CD. Regarding inverse associations with incident IBD, Helicobacter pylori and helminth infections were associated with a generally consistent reduced risk of IBD. Based on a qualitative analysis of the translational data, putative mechanisms involve multiple microbial and immunologic pathways.

CONCLUSIONS

Based on this systematic review, certain enteric pathogens are associated with an increased risk of incident IBD, while others are potentially protective. Prospective studies are required to clarify the clinical implications of these enteric pathogens on the risk and course of IBD, and possible therapeutic or preventative benefit.

Association between H. pylori infection and health Outcomes: an umbrella review of systematic reviews and meta-analyses

OBJECTIVE

Systematic reviews and meta-analyses have revealed the associations between H. pylori infection and various health outcomes. We aimed to evaluate the strength and breadth of evidence on the associations.

DESIGN

Umbrella review of systematic reviews and meta-analyses.

SETTING

No settings.

PARTICIPANTS

No patients involved.

DATA SOURCES

Embase, PubMed, Web of Science, Cochrane Library Databases, CNKI, VIP database and Wangfang database from inception to February 1, 2019.

OUTCOMES MEASURES

Diverse diseases (such as cancer and ischaemic heart disease).

RESULTS

Sixty articles reporting 88 unique outcomes met the eligible criteria. 74 unique outcomes had nominal significance (p<0.05). Of the outcomes with significance, 61 had harmful associations and 13 had beneficial associations. Furthermore, 73% (64) of the outcomes exhibited significant heterogeneity . Of the these meta-analyses, 32 had moderate to high heterogeneity (I²=50%-75%) and 24 had high heterogeneity (I²>75%). Moreover, 20% exhibited publication bias (p<0.1). In addition, 97% of the methodological qualities were rated 'critically low'. 36% of the evidence qualities of outcomes were rated 'low', 56% of the evidence qualities were rated 'very low' and 8% of the evidence qualities were rated 'moderate'. H. pylori infection may be associated with an increased risk of five diseases and a decreased risk of irritable bowel syndrome.

CONCLUSION

Although 60 meta-analyses explored 88 unique outcomes, moderate quality evidence only existed for six outcomes with statistical significance. H. pylori infection may be associated with a decreased risk of irritable bowel syndrome and an increased risk of hypertriglyceridemia, chronic cholecystitis and cholelithiasis, gestational diabetes mellitus, gastric cancer and systemic sclerosis.

TRIAL REGISTRATION

CRD42019124680.

Diagnosis and treatment of Helicobacter pylori infections in children and elderly populations

Helicobacter pylori (H. pylori) infection is associated with various gastric and extra-gastric diseases. Importantly, this infection is the strongest known risk factor for gastric cancer (GC). H. pylori eradication can effectively prevent H. pylori infection-associated diseases in H. pylori-positive patients, including children and elderly subjects. However, a limited selection of antibiotics, a higher reinfection rate, and certain spontaneous clearance rates, to some extent, restrict the choice of H. pylori treatments in pediatrics. In addition, it is imperative to perform an accurate diagnosis of H. pylori infection in children by determining the presence of the H. pylori infection and the underlying cause of symptoms. In elderly patients, poor tolerance to drugs and higher sensitivity to adverse effects are major concerns during H. pylori therapy. Recent studies have demonstrated that H. pylori eradication could significantly lower the GC risk in the elderly population. The benefit and risk of H. pylori eradication in elderly patients should be comprehensively considered and balanced. If available, susceptibility-based tailored therapies may be preferable in eradicating H. pylori. In addition, to increase the eradication rate and reduce adverse effects, new therapeutic strategies (e.g., probiotic supplementation, berberine supplementation, dual therapy) for H. pylori infection are being extensively investigated. The impact of H. pylori eradication with antibiotics on the microbiota in children has been explored, but further high-quality studies are crucial to delineate the extent of H. pylori eradication affecting the microbial community in children. In this review, we summarize the current understanding of H. pylori diagnosis and treatment in children and the elderly population and aim to provide insights into the efficient management and treatment implementation in these populations.

Eosinophilic esophagitis: pitfalls and controversies in diagnosis and management

Formerly considered a rare disorder, eosinophilic esophagitis (EoE) has emerged as a leading cause of feeding problems in children and an increasingly recognized cause of dysphagia and food impaction in adults. Our understanding of EoE and its complex interplay with gastro-esophageal reflux disease (GERD) has evolved over the past decade and culminated in the introduction of proton pump inhibitor (PPI) responsive EoE as a distinct entity which has added to this complexity. It is now clear that this entity is on the same spectrum as the original EoE, and that PPIs should be considered as part of treatment protocol and should not be recommended as a diagnostic tool. As such, removing the PPI trial from the diagnostic algorithm has been encouraged recently. Recent guidelines and reviews thoroughly address various aspects in EoE pathogenesis and diagnostic workup as well as management endpoints, treatment options and novel therapies. However, despite the recent extensive study and the advances in our knowledge of this disease, unmet needs and pitfalls in diagnostic workup and management of these patients are still to be clarified and will be under focus in this review.

Review: Helicobacter pylori and non-malignant upper gastrointestinal diseases

This review covers recent publications investigating the relationship between Helicobacter pylori infection and gastroesophageal reflux disease, Barrett's esophagus, eosinophilic esophagitis, peptic ulcer disease (PUD), H pylori gastritis, and functional dyspepsia. In the area of gastroesophageal reflux disease, new data suggest that reflux may have a role in the transmission of H pylori infection. In addition to several observational studies, data on alterations in esophageal physiology in patients with H pylori infection are presented. Further evidence for the inverse relationship between H pylori infection and Barrett's esophagus is available in the form of a meta-analysis from the North American Barrett's and Esophageal Carcinoma Consortium. The relationship between H pylori infection and eosinophilic esophagitis remains uncertain. Although new data do not indicate a significantly lower prevalence of H pylori among patients with eosinophilic esophagitis, a meta-analysis showed a 37% reduced risk of eosinophilic esophagitis among H pylori-infected patients. Novel data are presented on the genetic variability of bacterial virulence factors and their relationship with PUD. We also report data on plasma biomarkers, which may detect progression to gastric cancer in H pylori-associated PUD. A new meta-analysis was published, which assessed the risk of PUD in low-dose aspirin users with H pylori infection. Finally, we report on the ongoing attempts to stratify patients with gastritis using endoscopic methods when compared to standard biopsy examination.

Systematic review with meta-analysis: association between Helicobacter pylori CagA seropositivity and odds of inflammatory bowel disease

BACKGROUND

Accumulating data support a protective role of Helicobacter pylori against inflammatory bowel diseases (IBD), which might be mediated by strain-specific constituents, specifically cagA expression.

AIM

To perform a systematic review and meta-analysis to more clearly define the association between CagA seropositivity and IBD.

METHODS

We identified comparative studies that included sufficient detail to determine the odds or risk of IBD, Crohn's disease (CD) or ulcerative colitis (UC) amongst individuals with vs without evidence of cagA expression (eg CagA seropositivity). Estimates were pooled using a random effects model.

RESULTS

Three clinical studies met inclusion criteria. cagA expression was represented by CagA seropositivity in all studies. Compared to CagA seronegativity overall, CagA seropositivity was associated with lower odds of IBD (OR 0.31, 95% CI 0.21-0.44) and CD (OR 0.25, 95% CI 0.17-0.38), and statistically nonsignificant lower odds for UC (OR 0.68, 95% CI 0.35-1.32). Similarly, compared to H pylori non-exposed individuals, H pylori exposed, CagA seropositive individuals had lower odds of IBD (OR 0.26, 95% CI 0.16-0.41) and CD (OR 0.23, 95% CI 0.15-0.35), but not UC (OR 0.66, 0.34-1.27). However, there was no significant difference in the odds of IBD, CD or UC between H pylori exposed, CagA seronegative and H pylori non-exposed individuals.

CONCLUSION

We found evidence for a significant association between CagA seropositive H pylori exposure and reduced odds of IBD, particularly CD, but not for CagA seronegative H pylori exposure. Additional studies are needed to confirm these findings and define underlying mechanisms.