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

Roles of the components of the cag-pathogenicity island encoded type IV secretion system in Helicobacter pylori

The Helicobacter pylori (H. pylori) cytotoxin-associated gene pathogenicity island (cagPAI) encodes 31 genes that assemble the cag type IV secretion system (T4SS) apparatus, which includes structures such as the outer membrane core complex, periplasmic ring, inner membrane complex and bacterial hairs. These proteins interact with each other to inject CagA into the host gastric epithelium. There are also individual unique functions that help H. pylori interfere with host cellular pathways, modulate the immune response and colonize the host for a long time. However, the functions of some of the proteins remain unclear. This review summarizes what is known about the structure and function of these auxiliary components and discusses their role in H. pylori pathogenesis.

Impact of Helicobacter pylori Eradication on Inflammatory Bowel Disease Onset and Disease Activity: To Eradicate or Not to Eradicate?

Helicobacter pylori infection has significant epidemiological relevance due to the carcinogenic nature of this bacterium, which is potentially associated with cancer. When detected, it should ideally be eradicated using a treatment that currently involves a combination of gastric acid suppressors and multiple antibiotics. However, this treatment raises questions regarding efficacy and safety profiles in patients with specific comorbidities, including inflammatory bowel diseases (IBD). Eradication therapy for H. pylori includes components associated with adverse gastrointestinal events, such as Clostridioides difficile colitis. This necessitates quantifying this risk through dedicated studies to determine whether this antimicrobial treatment could be significantly associated with IBD relapse or exacerbation of pre-existing IBD, as well as whether it could potentially lead to the de novo onset of IBD. Although the available evidence is reassuring about the safety of eradication therapy in patients with IBD, it is limited, and there are no specific recommendations for this particular situation in the leading international IBD and H. pylori guidelines. Therefore, studies need to evaluate the efficacy and safety profiles of the available antimicrobial regimens for H. pylori eradication in patients with IBD, both in clinical trial settings and in real-life studies.

Bibliometric analysis of the correlation between H. pylori and inflammatory bowel disease

Background

Helicobacter pylori (H. pylori) infection is prevalent and associated with the development of various gastric diseases. On the other hand, inflammatory bowel disease (IBD) is an immune-related intestinal disorder influenced by factors like gut microbiota imbalance, genetic predisposition, and environmental influences. Despite extensive research on the H. pylori-IBD relationship, a comprehensive bibliometric analysis in this area is lacking. Therefore, this study aims to use bibliometric methods to explore research trends, hotspots, and frontiers in H. pylori and IBD-related research, offering valuable insights for future research and clinical practice.

Methods

We retrieved relevant literature on H. pylori and IBD from the Web of Science Core Collection (WoSCC) and Scopus databases covering 2007 to 2024. We perform a comprehensive analysis within the WoSCC literature. We compare these findings with relevant results from Scopus.

Results

Research on H. pylori and IBD has remained prominent in recent years. The United States leads in output, with strong contributions from authors, institutions, and journals. China, despite being a developing country, shows rapid article growth, signaling growing research potential. Key topics include Crohn's disease, gut microbiota, H. pylori infection, and ulcerative colitis. Newer interests include health, cancer prevention, and chronic gastritis.

Conclusion

Over the past, research on H. pylori and IBD has primarily centered around epidemiology and clinical studies. The question of whether H. pylori definitively offers protective effects against IBD remains unresolved. Therefore, further investigation could explore the underlying mechanisms of their relationship or initiate long-term prospective cohort studies to gather more compelling evidence.

Immunological relationship between Helicobacter pylori and anti-tumor necrosis factor α agents in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a group of diseases characterized by refractory and chronic inflammation of the bowel, which can be treated with biologics in clinical practice. Anti-tumor necrosis factor α (TNF-α) agents, which are among the most widely used biologics, alleviate the inflammatory activity in a variety of ways. Helicobacter pylori is a Gram-negative bacterium that colonizes the gastric mucosa, which could cause chronic inflammation and even induce gastric cancer. However, it has been suggested that H. pylori has a potential protective role in IBD patients. Yet there has been limited research on the mechanisms of the effect of H. pylori infection in IBD patients, and whether there is an interaction between H. pylori and anti-TNF-α agents. This review aims to summarize the possible mechanisms of H. pylori and anti-TNF-α agents in the development and treatment of IBD, and to explore the possible interaction between H. pylori infection and anti-TNF-α agents.

Helicobacter pylori in Inflammatory Bowel Diseases: Active Protagonist or Innocent Bystander?

Helicobacter pylori (H. pylori) infection is a prominent entity within human infectious diseases which cause chronic gastritis, peptic ulcers, gastric malignancies, and extragastric disorders. Its persistent colonization can lead to a systemic inflammatory cascade, potentially instigating autoimmune responses and contributing to the pathogenesis of autoimmune diseases. While the specific etiopathogenesis of inflammatory bowel diseases (IBDs) is still unknown, it is widely recognized that immunological, genetic, and environmental factors are implicated. Various bacterial and viral pathogens have been implicated in the pathogenesis of IBDs. Numerous studies suggest a correlation between H. pylori infection and IBDs. While subject to debate, this link suggests that the bacterium's presence somehow impacts the progression of IBDs by modifying the diversity of the gut microbiota, consequently altering local chemical profiles and disrupting the pattern of gut immune response. However, epidemiological evidence indicates a protective role of H. pylori infection against the onset of autoimmune diseases. Additionally, laboratory findings demonstrate H. pylori's capacity to promote immune tolerance and restrict inflammatory reactions. The aim of this review is to elucidate the proposed mechanisms and confounding factors that underlie the potential association between H. pylori infection and IBDs.

Detecting potential causal relationship between inflammatory bowel disease and rosacea using bi-directional Mendelian randomization

The association between rosacea and inflammatory bowel disease (IBD) has been studied in previous observational studies. It is unclear, however, whether the association is causal or not. Independent genetic variants for IBD were chosen as instruments from published Genome-wide association studies (GWAS) studies involving 38,155 cases with an IBD diagnosis and 48,485 controls in order to investigate the causal effect of IBD on rosacea. Summarized data for rosacea were gathered from various GWAS studies that included 1195 cases and 211,139 controls without rosacea. Reverse-direction Mendelian randomization (MR) analysis was done to investigate the relationship between genetically proxied rosacea and IBD. With the use of the inverse variance-weighted (IVW), MR-Egger, and weighted median approaches, a 2-sample Mendelian randomization study was carried out. Analysis of heterogeneity and sensitivity was performed to examine the pleiotropy and robustness of effect estimates. The forward-direction of the MR study was to reveal that genetic predisposition to IBD including its two main subtypes: Crohn's disease (CD) and ulcerative colitis (UC) was associated with an increased risk of rosacea. The reverse-direction MR analyses did not demonstrate that a genetic predisposition to rosacea was associated with total IBD, UC and CD. Our findings provided evidence for a causal impact of IBD, UC, and CD on rosacea, but not vice versa. The elevated incidence of rosacea in patients with IBD should be recognized by doctors to make an early diagnosis and initiate specialized therapy.

Immune response modulation in inflammatory bowel diseases by Helicobacter pylori infection

Many studies point to an association between Helicobacter pylori (H. pylori) infection and inflammatory bowel diseases (IBD). Although controversial, this association indicates that the presence of the bacterium somehow affects the course of IBD. It appears that H. pylori infection influences IBD through changes in the diversity of the gut microbiota, and hence in local chemical characteristics, and alteration in the pattern of gut immune response. The gut immune response appears to be modulated by H. pylori infection towards a less aggressive inflammatory response and the establishment of a targeted response to tissue repair. Therefore, a T helper 2 (Th2)/macrophage M2 response is stimulated, while the Th1/macrophage M1 response is suppressed. The immunomodulation appears to be associated with intrinsic factors of the bacteria, such as virulence factors - such oncogenic protein cytotoxin-associated antigen A, proteins such H. pylori neutrophil-activating protein, but also with microenvironmental changes that favor permanence of H. pylori in the stomach. These changes include the increase of gastric mucosal pH by urease activity, and suppression of the stomach immune response promoted by evasion mechanisms of the bacterium. Furthermore, there is a causal relationship between H. pylori infection and components of the innate immunity such as the NLR family pyrin domain containing 3 inflammasome that directs IBD toward a better prognosis.

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?

Trends and Complication Rates in Ulcerative Colitis Patients With and Without Helicobacter pylori Infections

Background Previous studies have shown an inverse relationship between ulcerative colitis (UC) and Helicobacter pylori infections (HPI). Though these two conditions have opposite geographic distributions, there may also be a physiological explanation for the decreased incidence of H. pylori infections in patients with UC. The purpose of this study is to analyze trends and complication rates of ulcerative colitis patients with and without HPI. Materials and methods The National Inpatient Sample (NIS) database was queried for patients with a primary diagnosis of UC, stratified by the presence of H. pylori infection. Patient demographics, length of stay, total hospital charges, and mortality were compared by H. pylori status. Additionally, complication rates were also compared between the two groups. Chi-squared and independent t-tests were used to compare outcomes and demographics, and multiple logistic regression was used to analyze primary and secondary outcomes. Results Patients with UC and HPI had a lower mortality rate (8.22 vs. 3.48, P<0.05, adjusted odds ratio [AOR] 0.33) and lower hospital charges ($65,652 vs. $47,557, p<0.05, AOR 1) with similar length of stay. Patients with UC and HPI also had lower rates of intestinal perforation (2.16% vs. 1.12%, p=0.05, AOR 0.408) and intrabdominal abscess formation (0.89% vs. 0.12%, AOR 0.165, p=0.072), though this difference was not significant. From 2001 to 2013, the incidence of UC has increased while the incidence of HPI has decreased. Conclusions The lower hospital charges and mortality rate as well as decreased rates of intestinal perforation and abscess formation suggest that there may be a physiologic role that HPI plays in modulating UC. Further studies into the interaction of these two conditions would be beneficial in clarifying their relationship and may help guide treatment of UC.

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.

Helicobacter pylori and unignorable extragastric diseases: Mechanism and implications

Considered as the most popular pathogen worldwide, Helicobacter pylori is intensively associated with diverse gastric diseases, including gastric ulcers, chronic progressive gastritis, and gastric cancer. Aside from its pathogenic effect on gastric diseases, growing evidences reveal that H. pylori may be related to numerous extragastric diseases. In this article, we reviewed recent studies and systematically elucidated that H. pylori may interfere with many biological processes outside the stomach and influence the occurrence of various extragastric diseases. Many epidemiological studies have indicated that H. pylori plays a pathogenic role in COVID-19, atherosclerosis, hyperemesis gravidarum and several other extragastric diseases, while the effect of H. pylori is currently under investigation in gastroesophageal reflux disease, asthma, and inflammatory bowel disease. Moreover, we also summarized the possible pathogenic mechanisms of H. pylori that may be related to chronic systemic inflammation and molecular mimicker. Taken together, this review provides a new perspective on the role of H. pylori in extragastric diseases and explores the possible mechanisms, which may help guide clinical treatment.

Helicobacter pylori infection in patients with inflammatory bowel diseases: a single-centre, prospective, observational study in Egypt

OBJECTIVE

Conflicting results have been reported by numerous epidemiological studies investigating the association between Helicobacter pylori (H. pylori) infection and inflammatory bowel disease (IBD). We aimed in this study to assess the possible association between H. pylori infection and IBD and its effects on disease progression.

DESIGN

Prospective observational study.

SETTING

Specialised IBD care clinics at Alexandria University Student Hospital in northern Egypt, between March and June 2019.

PARTICIPANTS

182 patients with IBD.

ANALYSIS AND OUTCOME MEASURES

Participants with IBD were screened for H. pylori infection and clinically evaluated at the initial visit and bimonthly for 3 months to record any potential improvement/flare of the IBD condition.

RESULTS

Overall, 90 (49.5%) patients with IBD had evidence of H. pylori infection. The course of IBD did not significantly differ in association with H. pylori infection or IBD treatment strategy. Cox regression analysis revealed that patients aged 20-35 years (HR=6.20 (95% CI: 1.74 to 22.12)) and 35-55 years (557.9 (17.4-17 922.8)), high socioeconomic status (2.9 (1.11-7.8)), daily consumption of fibre-rich food (5.1 (1.32-19.5)), occasional consumption of snacks between meals (2.8 (2.5-70.5)) and eating four meals per day (13.3 (1.0-7.7)) were predictive of IBD flare. By contrast, eating fruits and vegetables showed a strongly protective association (HR=0.001 (95% CI: 0.0002 to 0.02)). The probabilities of improvement of IBD symptoms after 12 weeks of follow-up were comparable in assessments based on H. pylori infection status (0.793 for H. pylori negative vs 0.778 for H. pylori positive) and IBD treatment option (0.811 for conventional therapy vs 0.750 for biological therapy).

CONCLUSION

The association between IBD and H. pylori infection is unresolved and should be further investigated in the context of specific environmental exposures that can influence the development or relapse of IBD.

Helicobacter Pylori and Autoimmune Diseases: Involving Multiple Systems

The modern Gastroenterology have witnessed an essential stride since Helicobacter pylori was first found in the stomach and then its pathogenic effect was discovered. According to the researches conducted during the nearly 40 years, it has been found that this bacterium is associated with a natural history of many upper gastrointestinal diseases. Epidemiological data show an increased incidence of autoimmune disorders with or after infection with specific microorganisms. The researches have revealed that H. pylori is a potential trigger of gastric autoimmunity, and it may be associated with other autoimmune diseases, both innate and acquired. This paper reviews the current support or opposition about H. pylori as the role of potential triggers of autoimmune diseases, including inflammatory bowel disease, autoimmune thyroiditis, type 1 diabetes mellitus, autoimmune liver diseases, rheumatoid arthritis, idiopathic thrombocytopenic purpura, systemic lupus erythematosus, as well as Sjogren’s syndrome, chronic urticaria and psoriasis, and tried to explain the possible mechanisms.

Insights into the underlying mechanisms and clinical management of microscopic colitis in relation to other gastrointestinal disorders

Microscopic colitis (MC) is a chronic inflammatory disease of the large intestine and as a relatively late recognized condition, its relationship with other disorders of the gastrointestinal tract is gradually being understood and investigated. As a multifactorial disease, MC interacts with inflammatory bowel disease, celiac disease, and irritable bowel syndrome through genetic overlap, immunological factors, and gut microflora. The risk of colorectal cancer was significantly lower in MC, gastrointestinal infections increased the risk of developing MC, and there was an inverse association between Helicobacter pylori infection and MC. A variety of associations are found between MC and other gastrointestinal disorders, where aspects such as genetic effects, resemblance of immunological profiles, and intestinal microecology are potential mechanisms behind the relationships. Clinicians should be aware of these connections to achieve a better understanding and management of MC.

Exosomal CagA from Helicobacter pylori aggravates intestinal epithelium barrier dysfunction in chronic colitis by facilitating Claudin-2 expression

BACKGROUND

The chronic infection with Helicobacter pylori (H. pylori), especially cytotoxin-associated gene A-positive (CagA⁺) strains, has been associated with various extragastric disorders. Evaluating the potential impacts of virulence factor CagA on intestine may provide a better understanding of H. pylori pathogenesis such as colitis. The intestinal mucosal barrier is essential for maintaining its integrity and functions. However, how persistent CagA⁺ H. pylori colonization influences barrier disruption and thereby affects chronic colitis is not fully understood.

RESULTS

Chronic colitis models of CagA⁺ H. pylori-colonized mice treated with 2% Dextran sulphate sodium (DSS) were established to assess the disease activity and pertinent expression of tight junction proteins closely related to mucosal integrity. The aggravating effect of CagA⁺ H. pylori infection on DSS-induced chronic colitis was confirmed in mouse models. In addition, augmented Claudin-2 expression was detected in CagA⁺ H. pylori infection conditions and selected for mechanistic analysis. Next, GES-1 human gastric epithelial cells were cultured with CagA⁺ H. pylori or a recombinant CagA protein, and exosomes isolated from conditioned media were then identified. We assessed the Claudin-2 levels after exposure to CagA⁺ exosomes, CagA^- exosomes, and IFN-γ incubation, revealing that CagA⁺ H. pylori compromised the colonic mucosal barrier and facilitated IFN-γ-induced intestinal epithelial destruction through CagA-containing exosome-mediated mechanisms. Specifically, CagA upregulated Claudin-2 expression at the transcriptional level via a CDX2-dependent mechanism to slow the restoration of wounded mucosa in colitis in vitro.

CONCLUSIONS

These data suggest that exosomes containing CagA facilitate CDX2-dependent Claudin-2 maintenance. The exosome-dependent mechanisms of CagA⁺ H. pylori infection are indispensable for damaging the mucosal barrier integrity in chronic colitis, which may provide a new idea for inflammatory bowel disease (IBD) treatment.

Helicobacter pylori may participate in the development of inflammatory bowel disease by modulating the intestinal microbiota

Inflammatory bowel disease (IBD) is a non-specific inflammatory disease of the gastrointestinal (GI) tract that is generally accepted to be closely related to intestinal dysbiosis in the host. GI infections contribute a key role in the pathogenesis of IBD; however, although the results of recent clinical studies have revealed an inverse correlation between Helicobacter pylori (H. pylori) infection and IBD, the exact mechanism underlying the development of IBD remains unclear. H. pylori, as a star microorganism, has been a focus for decades, and recent preclinical and real-world studies have demonstrated that H. pylori not only affects the changes in the gastric microbiota and microenvironment but also influences the intestinal microbiota, indicating a potential correlation with IBD. Detailed analysis revealed that H. pylori infection increased the diversity of the intestinal microbiota, reduced the abundance of Bacteroidetes, augmented the abundance of Firmicutes, and produced short-chain fatty acid-producing bacteria such as Akkermansia. All these factors may decrease vulnerability to IBD. Further studies investigating the H. pylori-intestinal microbiota metabolite axis should be performed to understand the mechanism underlying the development of IBD.

The role of gastrointestinal pathogens in inflammatory bowel disease: a systematic review

The inflammatory bowel diseases (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), are chronic, progressive, inflammatory conditions of the gastrointestinal tract. Imbalance in the gut microbial community, or dysbiosis, and the subsequent immune response, represent the critical relationship between genetic susceptibility, microbes, and environment factors, that result in IBD. Gastrointestinal pathogens - a common cause of dysbiosis - have been implicated as an environmental trigger in new onset IBD, as well as flare of existing IBD. In this article, we systematically review clinical data regarding the association between specific gastrointestinal pathogens and IBD. Numerous bacteria, viruses, fungi, and parasites have been implicated in the pathogenesis of IBD, and exacerbations of existing disease. In this article, we will also specifically discuss the less recognized microbes that have an inverse association with IBD, including certain bacterial pathogens, such as Helicobacter pylori, and parasites, such as Trichuris species. Future prospective and experimental studies are required to establish causality and clarify potential mechanisms of enteric pathogens in modifying the risk and course of IBD.

The prevalence of Helicobacter pylori infection in inflammatory bowel disease in China: A case-control study

Background & aims

Helicobacter pylori (H. pylori) infection remains high in China though the incidence of inflammatory bowel disease (IBD) has increased. Our aim was to investigate the relationship between the prevalence of H. pylori and inflammatory bowel disease.

Methods

Hospitalized IBD patients including Crohn’s disease (CD) and ulcerative colitis (UC) who had tested H. pylori antibody were enrolled. Controls were chose from age- and sex- matched healthy physical examination people who had H. pylori antibody test in a 1:2 fashion (IBD patients:controls). IBD medical history was recorded. All patients were typed by the Montreal classification. Mayo Clinic score and the Harvey-Bradshaw Severity Index were used to evaluate their disease activity. Patients and controls that had H. pylori eradication therapy before were excluded.

Results

Two hundred and sixty IBD patients including 213 CD patients and 47 UC patients, and 520 controls were involved in this study. The prevalence of H. pylori infection in IBD patients (9.6%, 25/260) and IBD newly diagnosed patients (12.1%, 8/66), as well as CD patients (8.9%, 19/213) including CD newly diagnosed patients (10.6%, 5/47) and UC patients (12.8%, 6/47) was significantly lower than controls (29.8%, 155/520) (p = 2.796*10⁻¹⁰, 0.007, 5.723*10⁻⁹, 0.016, 0.014), while there was no statistically difference between UC newly diagnosed patients and the controls, and IBD patients with different disease type, disease activity and treatment history.

Conclusions

H. pylori infection had a negative association with IBD, especially CD.

Trends in the epidemiology of inflammatory bowel disease in Colombia by demographics and region using a nationally representative claims database and characterization of inflammatory bowel disease phenotype in a case series of Colombian patients

The incidence of inflammatory bowel disease (IBD) is on the rise in Latin America. The aims of this study were to examine epidemiologic trends of IBD in Colombia by demographics, region, urbanicity, and to describe the IBD phenotype in a large well-characterized Colombian cohort.We used a national database of 33 million adults encompassing 97.6% of the Colombian population in order to obtain epidemiologic trends of IBD using International Classification of Diseases 10codes for adults with ulcerative colitis (UC) and Crohn disease (CD). We calculated the incidence and prevalence of UC and CD from 2010-2017 and examined epidemiologic trends by urbanicity, demographics, and region. We then examined the IBD phenotype (using Montreal Classification), prevalence of IBD-related surgeries, and types of IBD-medications prescribed to adult patients attending a regional IBD clinic in Medellin, Colombia between 2001 and 2017.The incidence of UC increased from 5.59/100,000 in 2010 to 6.3/100,000 in 2017 (relative risk [RR] 1.12, confidence interval (CI) (1.09-1.18), P < .0001). While CD incidence did not increase, the prevalence increased within this period. The Andes region had the highest incidence of IBD (5.56/100,000 in 2017). IBD was seen less in rural regions in Colombia (RR=.95, CI (0.92-0.97), p < .01). An increased risk of IBD was present in women, even after adjusting for age and diagnosis year (RR 1.06 (1.02-1.08), P = .0003). The highest IBD risk occurred in patients 40 to 59 years of age. In the clinic cohort, there were 649 IBD patients: 73.7% UC and 24.5% CD. Mean age of diagnosis in CD was 41.0 years and 39.9 years in UC. UC patients developed mostly pancolitis (43%). CD patients developed mostly ileocolonic disease and greater than a third of patients had an inflammatory, non-fistulizing phenotype (37.7%). A total of 16.7% of CD patients had perianal disease. CD patients received more biologics than UC patients (odds ratio: 3.20, 95% CI 2.19-4.69 P < .001).Using both a national representative sample and a regional clinic cohort, we find that UC is more common in Colombia and is on the rise in urban regions; especially occurring in an older age cohort when compared to Western countries. Future studies are warranted to understand evolving environmental factors explaining this rise.

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: 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.

The effect of antibiotic resistance on Helicobacter pylori eradication efficacy: A systematic review and meta-analysis

BACKGROUND

The occurrence of antibiotic-resistant strains has been rapidly increasing due to the wide use of antibiotics. To evaluate the current effects of antibiotic resistance on Helicobacter pylori eradication efficacy, we conducted this systematic review and meta-analysis.

METHODS

Literature searches were conducted in the following databases: PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Statistical analysis was performed using STATA version 12.0 (StataCorp LP, College Station, TX, USA).

RESULTS

A total of 120 studies, including 28 707 patients, were assessed. Only first-line therapy was considered. The pooled RR of eradication rate in patients with Helicobacter pylori strains sensitive versus resistant to clarithromycin was 0.682 (95% CI: 0.636-0.731). The pooled RR of eradication rate in patients with Helicobacter pylori strains sensitive versus resistant to metronidazole was 0.843 (95% CI: 0.810-0.877). The pooled RR of eradication rate in patients with Helicobacter pylori strains sensitive versus resistant to levofloxacin was 0.794 (95% CI: 0.669-0.941). The pooled RR of eradication rate in patients with Helicobacter pylori strains sensitive versus resistant to dual clarithromycin and metronidazole was 0.674 (95% CI: 0.590-0.770).

CONCLUSION

Antibiotic resistance causes a decrease in the eradication rate of H pylori today. Quadruple concomitant therapy may overcome the declining H pylori eradication rate caused by metronidazole-only resistance.

The relationship between inflammatory bowel disease and Helicobacter pylori across East Asian, European and Mediterranean countries: a meta-analysis

Background

The current literature suggests a protective benefit of Helicobacter pylori (H. pylori) infection against inflammatory bowel disease (IBD). Here we assessed whether this effect varied by IBD subtype—Crohn’s disease (CD) or ulcerative colitis (UC)—and geographic region: East Asia, Europe (non-Mediterranean) or Mediterranean region.

Methods

A database search was performed up to July 2019 inclusive for all studies that compared H. pylori infection in IBD patients vs. non-IBD controls. The relative risk (RR) was used to quantify the association between IBD and H. pylori, and the effects were combined across studies using a mixed-effects meta-regression model, which included IBD subtype and geographic region as categorical moderator variables.

Results

Our meta-regression model exhibited moderate heterogeneity (I²=48.74%). Pooled RR depended on both region (P=0.02) and subtype (P<0.001). Pooled RRs were <1 for all subtype and region combinations, indicative of a protective effect of H. pylori against IBD. The pooled RR was 28% (9%, 50%; P=0.001) greater for UC vs. CD and 43% (4%, 96%; P=0.02) greater for Mediterranean countries vs. East Asia. The pooled RR was 18% (-13%, 60%; P=0.48) greater for Europe vs. East Asia and 21% (-13%, 68%; P=0.42) greater for Mediterranean vs. Europe, though these differences were not statistically significant.

Conclusions

The protective effect of H. pylori on IBD varied by both subtype (more protection against CD vs. UC) and region (East Asia more protected than Mediterranean regions). Variation due to these effects could provide insight into IBD etiology.

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.

Viewpoint: Inflammatory Bowel Diseases Among Immigrants From Low- to High-Incidence Countries: Opportunities and Considerations

The inflammatory bowel diseases [IBDs], inclusive of Crohn's disease [CD] and ulcerative colitis [UC], are chronic, progressive immune-mediated diseases associated with high morbidity and substantial economic impact. The pathogenesis implicates a complex interaction between environmental determinants and genetic susceptibility. Of concern, the incidence and prevalence of IBD are increasing globally, with the highest relative increase observed in developing and recently developed countries. One high-risk yet underappreciated population is immigrants from countries of low to high IBD incidence, as evidenced by epidemiologic studies demonstrating higher risk of IBD among second- versus first-generation and younger versus older immigrants from low- to high-incidence countries [LTHICs]. The reasons underlying these emerging patterns among immigrants are incompletely understood and provide enormous opportunities to better define the pathophysiology of IBD and move toward disease prevention or at least earlier diagnosis. The rapidity of this epidemiologic shift in the demographic profile of IBD, which was traditionally a disease of Caucasians in industrialized countries, strongly implicates non-genetic factors and gene-environment interactions in the pathophysiology of IBD among immigrants from LTHICs. The primary objectives of this Viewpoint are to [1] provide a focused overview of IBD epidemiology among immigrants from countries at differential IBD risk; [2] emphasize the potential to advance our understanding of IBD pathogenesis via targeted research efforts to delineate risk and protective determinants in this cohort; and [3] highlight disparities and barriers in IBD care, as well as the economic implications of the rising, yet underappreciated, disease burden among immigrants from LTHICs.

Hellenic consensus on Helicobacter pylori infection

The Hellenic Society of Gastroenterology recently organized the “Hellenic consensus on Helicobacter pylori (H. pylori) infection”. The aim of this publication is to report the guidelines in order to aid the national gastroenterology community in the management of H. pylori infection. Forty-one delegates from all Greek regions, including gastroenterologists, pathologists, clinical microbiologists, epidemiologists and basic scientists, were invited to this meeting. The participants were allocated to 1 of the 4 main topics of the meeting: i.e., H. pylori diagnosis and association with diseases; H. pylori and gastric cancer; H. pylori and extragastric associated disorders; and H. pylori treatment. The results of each subgroup were submitted to a final consensus vote that included all participants. Relevant data based on international and Greek publications were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. The cutoff level of 70% was considered as acceptance for the final statement. It is hoped that the recommendations and conclusions of this report will guide Greek doctors in their daily practice concerning the management of H. pylori infection.