Kyoto global consensus report on Helicobacter pylori gastritis

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

The Application of the Rome IV Criteria to Functional Esophagogastroduodenal Disorders in Asia

The Rome criteria were amended as Rome IV. For functional esophageal disorders, the exclusion criteria have been more specifically revised based on further understanding of other esophageal disorders, including eosinophilic esophagitis and spastic and hypercontractile motor disorders. Another revised point is the more restrictive definition of gastroesophageal reflux disease, indicating that sensitivity to a physiological reflux burden may be placed more firmly within the functional group. For functional dyspepsia (FD), only minor changes were introduced, mainly to improve specificity. Among the major symptoms of FD, not only postprandial fullness, but also epigastric pain, epigastric burning, and early satiation should be "bothersome." Investigation on the effect of meal ingestion on symptom generation has indicated that not only postprandial fullness and early satiety, but also epigastric pain, epigastric burning sensation and nausea (not vomiting) may increase after meals. Helicobacter pylori infection is considered a possible cause of dyspepsia if successful eradication leads to sustained resolution of symptoms for more than 6 months, and such status can be termed as "H. pylori-associated dyspepsia." Prompt esophagogastroduodenoscopy and H. pylori testing and treatment would be more beneficial, especially in Asia, which has a high prevalence of gastric cancer. Acotiamide, tandospirone, and rikkunshito are the newly listed as treatment options for FD. For further therapeutic development, clinical studies based on the strict Rome IV criteria should be performed.

Risk of stomach cancer in Aotearoa/New Zealand: A Māori population based case-control study

Māori, the indigenous people of New Zealand, experience disproportionate rates of stomach cancer, compared to non-Māori. The overall aim of the study was to better understand the reasons for the considerable excess of stomach cancer in Māori and to identify priorities for prevention. Māori stomach cancer cases from the New Zealand Cancer Registry between 1 February 2009 and 31 October 2013 and Māori controls, randomly selected from the New Zealand electoral roll were matched by 5-year age bands to cases. Logistic regression was used to estimate odd ratios (OR) and 95% confidence intervals (CI) between exposures and stomach cancer risk. Post-stratification weighting of controls was used to account for differential non-response by deprivation category. The study comprised 165 cases and 480 controls. Nearly half (47.9%) of cases were of the diffuse subtype. There were differences in the distribution of risk factors between cases and controls. Of interest were the strong relationships seen with increased stomach risk and having >2 people sharing a bedroom in childhood (OR 3.30, 95%CI 1.95–5.59), testing for H pylori (OR 12.17, 95%CI 6.15–24.08), being an ex-smoker (OR 2.26, 95%CI 1.44–3.54) and exposure to environmental tobacco smoke in adulthood (OR 3.29, 95%CI 1.94–5.59). Some results were attenuated following post-stratification weighting. This is the first national study of stomach cancer in any indigenous population and the first Māori-only population-based study of stomach cancer undertaken in New Zealand. We emphasize caution in interpreting the findings given the possibility of selection bias. Population-level strategies to reduce the incidence of stomach cancer in Māori include expanding measures to screen and treat those infected with H pylori and a continued policy focus on reducing tobacco consumption and uptake.

Helicobacter pylori vacA genotype is a predominant determinant of immune response to Helicobacter pylori CagA

AIM

To evaluate the frequency of Helicobacter pylori (H. pylori) CagA antibodies in H. pylori infected subjects and to identify potential histopathological and bacterial factors related to H. pylori CagA-immune response.

METHODS

Systematic data to H. pylori isolates, blood samples, gastric biopsies for histological and molecular analyses were available from 99 prospectively recruited subjects. Serological profile (anti-H. pylori, anti-CagA) was correlated with H. pylori isolates (cagA, EPIYA, vacA s/m genotype), histology (Sydney classification) and mucosal interleukin-8 (IL-8) mRNA and protein expression. Selected H. pylori strains were assessed for H. pylori CagA protein expression and IL-8 induction in co-cultivation model with AGS cells.

RESULTS

Thirty point three percent of microbiologically confirmed H. pylori infected patients were seropositive for CagA. Majority of H. pylori isolates were cagA gene positive (93.9%) with following vacA polymorphisms: 42.4% vacA s1m1, 23.2% s1m2 and 34.3% s2m2. Anti-CagA-IgG seropositivity was strongly associated with atrophic gastritis, increased mucosal inflammation according to the Sydney score, IL-8 and cagA mRNA expression. VacA s and m polymorphisms were the major determinants for positive (vacA s1m1) or negative (vacA s2m2) anti-CagA serological immune response, which also correlated with the in vitro inflammatory potential in AGS cells. In vitro co-cultivation of representative H. pylori strains with AGS cells confirmed functional CagA translocation, which showed only partial correlation with CagA seropositivity in patients, supporting vacA as major co-determinant of the immune response.

CONCLUSION

Serological immune response to H. pylori cagA+ strain in H. pylori infected patients is strongly associated with vacA polymorphism, suggesting the crucial role of bacterial factors in immune and clinical phenotype of the infection.

Update on the first-line treatment for Helicobacter pylori infection - a continuing challenge from an old enemy

Because the prevalence of antibiotic resistance markedly increases with time worldwide, anti-H. pylori treatment is continuing to be a great challenge forsphysicians in clinical practice. The Real-world Practice & Expectation of Asia-Pacific Physicians and Patients in Helicobacter Pylori Eradication (REAP-HP) Survey demonstrated that the accepted minimal eradication rate of anti-H. pylori regimen in H. pylori-infected patients was 91%. The Kyoto Consensus Report on Helicobacter Pylori Gastritis also recommended that, within any region, only regimens which reliably produce eradication rates of ≥90% in that population should be used for empirical treatment. This article is aimed to review current first-line eradication regimens with a per-protocol eradication rate exceeding 90% in most geographic areas. In regions with low (≦15%) clarithromycin resistance, 14-day hybrid (or reverse hybrid), 10 ~ 14-day sequential, 7 ~ 14-day concomitant, 10 ~ 14-day bismuth quadruple or 14-day triple therapy can achieve a high eradication rate in the first-line treatment of H. pylori infection. However, in areas with high (>15%) clarithromycin resistance, standard triple therapy should be abandoned because of low eradication efficacy, and 14-day hybrid (or reverse hybrid), 10 ~ 14-day concomitant or 10 ~ 14-day bismuth quadruple therapy are the recommended regimens. If no recent data of local antibiotic resistances of H. pylori strains are available, universal high efficacy regimens such as 14-day hybrid (or reverse hybrid), concomitant or bismuth quadruple therapy can be adopted to meet the recommendation of consensus report and patients’ expectation.

Long-term effect of Helicobacter pylori eradication combined with folate in patients with chronic atrophic gastritis

AIM

To investigate the long-term effect of Helicobacter pylori (H. pylori) eradication combined with folate in patients with chronic atrophic gastritis (CAG).

METHODS

One hundred and twenty-three patients who underwent H. pylori eradication from July 2013 to June 2014 at our hospital were enrolled and divided into a combination group (n = 71) and a single eradication group (n = 52). Patients in the single eradication group were given standard triple H. pylori eradication therapy, and cases in the combination group were given folate for 3 mo after H. pylori eradication. All cases were followed at 2 years after treatment. The stages of operative link for gastric intestinal metaplasia assessment (OLGIM) and operative link for gastritis assessment (OLGA) were compared between the two groups before and after treatment. Patients in the combination group were further divided into an H. pylori successful eradication group (n = 49) and an H. pylori reinfection group (n = 22) according to the result of ¹³C urea breath test, and CAG lesion score was compared among the three groups before and after treatment.

RESULTS

The stages of OLGIM and OLGA in the combination group were significantly better than those in the single eradication group at 2 years after treatment (P < 0.05). CAG lesion scores in the H. pylori successful eradication group and single eradication group at 2 years after treatment were significantly lower than those before treatment in the same group (P < 0.05), but there was no significant difference in CAG lesion score between before and after treatment in the H. pylori reinfection group (P > 0.05). After treatment, CAG lesion score in the H. pylori successful eradication group was significantly lower than those in the H. pylori reinfection group and single eradication group (P < 0.05), although there was no significant difference in CAG lesion score between the H. pylori reinfection group and single eradication group after treatment (P > 0.05).

CONCLUSION

H. pylori eradication combined with folate treatment could significantly improve gastric mucosal atrophy and intestinal metaplasia in patients with CAG, and promote disease recovery, with satisfactory long-term effect, especially for patients with successful H. pylori eradication.

The Human Stomach in Health and Disease: Infection Strategies by Helicobacter pylori

Helicobacter pylori is a bacterial pathogen which commonly colonizes the human gastric mucosa from early childhood and persists throughout life. In the vast majority of cases, the infection is asymptomatic. H. pylori is the leading cause of peptic ulcer disease and gastric cancer, however, and these outcomes occur in 10-15% of those infected. Gastric adenocarcinoma is the third most common cause of cancer-associated death, and peptic ulcer disease is a significant cause of morbidity. Disease risk is related to the interplay of numerous bacterial host and environmental factors, many of which influence chronic inflammation and damage to the gastric mucosa. This chapter summarizes what is known about health and disease in H. pylori infection, and highlights the need for additional research in this area.

Helicobacter pylori-Induced Changes in Gastric Acid Secretion and Upper Gastrointestinal Disease

Appropriate management of Helicobacter pylori infection of the human stomach is evolving and remains a significant clinical challenge. Acute infection results in hypochlorhydria, whereas chronic infection results in either hypo- or hyperchlorhydria, depending upon the anatomic site of infection. Acute hypochlorhydria facilitates survival of the bacterium and its infection of the stomach. Interestingly, most patients chronically infected with H. pylori manifest a pangastritis with reduced acid secretion due to bacterial virulence factors, inflammatory cytokines, and various degrees of gastric atrophy. While these patients are predisposed to develop gastric adenocarcinoma (~1%), there is increasing evidence from population studies that they are also protected from gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), and esophageal adenocarcinoma (EAC). Eradication of H. pylori, in these patients, may provoke GERD in predisposed individuals and may be a contributory factor for the rising incidence of refractory GERD, BE, and EAC observed in Westernized societies. Only ~10% of chronically infected patients, mainly the young, manifest an antral predominant gastritis with increased acid secretion due to a decrease in somatostatin and increase in gastrin secretion; these patients are predisposed to develop peptic ulcer disease. H. pylori-induced changes in acid secretion, in particular hypochlorhydria, may allow ingested microorganisms to survive transit through the stomach and colonize the distal intestine and colon. Such perturbation of gut microbiota, i.e. dysbiosis, may influence human health and disease.

Management of Helicobacter pylori Infection: What Should the Surgeon Know?

Infection with Helicobacter pylori continues to represent a major global health care burden, and various national and international consensus reports and guidelines have aimed at tracking recent developments for their translation into an optimized clinical management. The most important 'innovation' is the definition of H. pylori gastritis as an infectious disease. This does imply the consideration of therapy of this condition even before the development of clinical manifestations including non-malignant and malignant gastroduodenal diseases, such as peptic ulcer disease, gastric cancer, and gastric mucosa-associated lymphoid tissue lymphoma. Treatment of H. pylori is facing an increasing number of failures, with the main reason being an increasing antibiotic resistance to some of the previously most effective antibiotics, i.e. clarithromycin and levofloxacin, for H. pylori strains. Several new treatment options or modifications of already established regimens have been introduced to overcome bacterial resistance and treatment failure. In this review, we provide an update on the current recommendations for a successful management of H. pylori infection, and in this context a special reference is made to the role of visceral surgeons.

Gastric adenocarcinoma

Gastric cancers, with gastric adenocarcinoma (GAC) as the most common histological type, impose a considerable global health burden. Although the screening strategies for early detection have been shown to be successful in Japan and South Korea, they are either not implemented or not feasible in most of the world, leading to late diagnosis in most patients. Helicobacter pylori infection contributes to the development of many endemic GACs, and pre-emptive eradication or early treatment of this bacterial infection might provide effective primary prevention. GACs are phenotypically and genotypically heterogeneous. Localized (clinical stage I) GAC is best treated either endoscopically or with limited surgical resection, but clinical stage II or stage III tumours require multidisciplinary adjunctive approaches in addition to surgery. Although GAC is highly treatable in its early stages, advanced (clinical stage IV) GAC has a median survival of just ∼9-10 months. However, detailed molecular and immune profiling of GAC is yielding promise; early studies with immune checkpoint inhibitors suggest that GAC is amenable to immune modulation. Molecular studies have yielded a vast quantity of new information for potential exploitation. Nevertheless, advances against GACs have lagged compared with other tumours of similar incidence, and more research is necessary to overcome the obstacles to prolong survival.

Consensus on the clinical management, screening-to-treat, and surveillance of Helicobacter pylori infection to improve gastric cancer control on a nationwide scale

BACKGROUND

Previous international consensus statements provided general policies for the management of Helicobacter pylori infection. However, there are geographic differences in the prevalence and antimicrobial resistance of H. pylori, and in the availability of medications and endoscopy. Thus, nationwide or regional consensus statements are needed to improve control of H. pylori infection and gastric cancer.

MATERIALS AND METHODS

This consensus statement for management of H. pylori in Taiwan has three major sections: (1) optimal diagnosis and indications; (2) current treatment strategies; and (3) screening-to-treat and surveillance for control of gastric cancer. The literature review emphasized recent data for development of draft statements and determination of levels of evidence. Twenty-five Taiwan experts conducted a consensus conference, by a modified Delphi process, to modify the draft statements. Consensus, defined as an agreement of least 80% of the experts, and recommendation grade were determined by anonymous voting.

RESULTS

There were 24 consensus statements. Section 1 has seven statements on recommendations for the diagnosis and indications for treatment of H. pylori infection. Section 2 has 10 statements that provide an updated treatment algorithm for first-line, second-line, and third-line regimens. Section 3 has seven statements regarding H. pylori eradication for reducing the risk of gastric cancer, with a cost-benefit analysis. After H. pylori eradication, the consensus highlights the use of endoscopic surveillance and/or chemoprevention to further reduce the burden of gastric cancer.

CONCLUSIONS

This consensus statement has updated recommendations for improving the clinical management of H. pylori infection in areas such as Taiwan, which have high prevalence of H. pylori infection and gastric cancer.

Vonoprazan improves the efficacy of Helicobacter pylori eradication therapy with a regimen consisting of clarithromycin and metronidazole in patients allergic to penicillin

BACKGROUND

Although all Helicobacter pylori (H. pylori)-positive patients should receive eradication therapy, the therapy is a challenge for patients allergic to penicillin. There have been a few reports on the efficacy of eradication therapy for such patients.

OBJECTIVE

To analyze the efficacy of vonoprazan or proton pump inhibitor (PPI)-based 7-day triple therapy in patients allergic to penicillin.

MATERIALS AND METHODS

A total of 88 consecutive patients allergic to penicillin who received H. pylori eradication therapy were retrospectively analyzed. Thirty-one patients had a history of failed eradication therapy. Four 7-day regimens were prescribed during the study period: clarithromycin-metronidazole-PPI (13 patients), clarithromycin-metronidazole-vonoprazan (14 patients), metronidazole-sitafloxacin-PPI (44 patients) and metronidazole-sitafloxacin-vonoprazan (17 patients). A ¹³ C-urea breath test was used for confirmation of eradication, and efficacy of eradication was evaluated by "intention-to-treat" analysis and "per-protocol" analysis.

RESULTS

Intention-to-treat and per-protocol eradication rates were 46.2%/54.6% for patients who received clarithromycin-metronidazole-PPI, 92.9/92.9% for patients who received clarithromycin-metronidazole-vonoprazan, 100/100% for patients who received metronidazole-sitafloxacin-PPI and 88.2/93.8% for patients who received metronidazole-sitafloxacin-vonoprazan. For first eradication, vonoprazan significantly raised the intention-to-treat efficacy of the triple therapy including clarithromycin-metronidazole (vonoprazan: 92.9%, PPI: 46.2%, P=.0128). A 7-day regimen consisting of metronidazole and sitafloxacin was effective for patients allergic to penicillin with or without past failure of eradication.

CONCLUSION

For first eradication in patients allergic to penicillin, a 7-day triple therapy consisting of clarithromycin, metronidazole and vonoprazan could be a candidate eradication regimen.

Screening and treating Helicobacter pylori infection for gastric cancer prevention on the population level

Helicobacter pylori infection is the major cause of gastric cancer, and removal of H. pylori infection from a population could theoretically decrease the number of cases by about 89%. However, in real-life settings, few studies have reported the effect of screening and treating this pathogen in population-based programs. This is mainly because of the lack of an adequate infrastructure for delivery of systematic screening services to asymptomatic individuals, the lack of standardization to ensure that each subject receives the correct diagnostic testing and antibiotic treatment, and limited resources. We illustrate our method of implementing two population-based screen-and-treat programs in Taiwan, where the epidemiological characteristics of disease burden have changed from the traditionally Eastern pattern towards that of the Western countries. Our first example is a high-risk population that resides on an offshore island, in which a strategy of mass eradication of H. pylori was applied. The other example is an intermediate-risk population, which is representative of the general average-risk population, in which there is integration of the screen-and-treat method with the established framework of colorectal cancer screening using the fecal-occult blood test. The information provided here may be useful for integration of gastric cancer prevention measures into the healthcare priorities of populations with different gastric cancer risks, such as those with limited resources.

Real-world practice and Expectation of Asia-Pacific physicians and patients in Helicobacter Pylori eradication (REAP-HP Survey)

OBJECTIVE

The aims of the study were: 1, to survey the most popular anti-H. pylori regimens in Asia-Pacific region and the real-world effectiveness of these regimens; and 2, to investigate the expectation gaps of eradication rate between physicians and patients.

DESIGN

A questionnaire was distributed to Asia-Pacific physicians who attended the Asia-Pacific Digestive Week 2015 meeting. Reported eradication rates from the literatures were compared with real-world rates of surveyed popular regimens within the region. In addition, a questionnaire was distributed to H. pylori-infected patients in three regions of Taiwan.

RESULTS

A total of 691 physicians and 539 patients participated in the survey. The top five most commonly used regimens were 7-day clarithromycin-based standard triple therapy (50.4%), 14-day clarithromycin-based standard triple therapy (31.0%), 10-day sequential therapy (6.1%), 14-day bismuth quadruple therapy (3.9%), and 14-day hybrid therapy (3.6%). All countries except for China had a significant gap between the expectation of physicians on anti-H. pylori therapy and the real-world eradication rate of most commonly adopted regimens (all P value <.05). The expectation on minimal eradication rate among patients was higher than that of physicians (91.4% vs 86.5%, P<.001).

CONCLUSIONS

It is time for physicians in Asia-Pacific countries to adopt newer and more efficacious anti-H. pylori regimens to meet the Kyoto consensus recommendation and their patients' expectations.

Current prevalence of Helicobacter pylori infection in patients with dyspepsia treated in Warsaw, Poland

INTRODUCTION

The prevalence of Helicobacter pylori (Hp) infection in patients with dyspepsia has important clinical and epidemiological implications. However, the current prevalence of Hp infection among patients within Poland is unknown; the last data were collected a decade ago and the majority of previous studies showed the prevalence to be between 60% and 100%.

AIM

To establish the current prevalence of Hp infection among patients with dyspepsia in Warsaw, Poland.

MATERIAL AND METHODS

The study group comprised 148 patients (126 women and 22 men) with dyspepsia, treated in two outpatient clinics in Warsaw. The mean age in the group that tested positive for Hp was 45.8 years (SD = 14.86; median = 51; min = 19; max = 64). They were tested for Hp infection with a urea breath test that uses 13C-enriched urea and isotope ratio mass spectrometry.

RESULTS

Helicobacter pylori infection was found in 53 patients (44 women and 9 men), i.e. in 35.8% of the whole study group. We did not find any significant relationship between Hp infection and the patients' age, gender, or their body mass index.

CONCLUSIONS

The current prevalence of Hp infection among patients with dyspepsia treated in Warsaw is 35.8%. However, our data suggest almost a two-fold fall in the prevalence of Hp infection compared to the previous Polish studies.

Novel and Effective Therapeutic Regimens for Helicobacter pylori in an Era of Increasing Antibiotic Resistance

Helicobacter pylori (H. pylori) is a common gastrointestinal bacterial strain closely associated with the incidence of chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. A current research and clinical challenge is the increased rate of antibiotic resistance in H. pylori, which has led to a decreased H. pylori eradication rate. In this article, we review recent H. pylori infection and reinfection rates and H. pylori resistance to antibiotics, and we discuss the pertinent treatments. A PubMed literature search was performed using the following keywords: Helicobacter pylori, infection, reinfection, antibiotic resistance, bismuth, proton pump inhibitors, vonoprazan, susceptibility, quintuple therapy, dual therapy, and probiotic. The prevalence of H. pylori has remained high in some areas despite the decreasing trend of H. pylori prevalence observed over time. Additionally, the H. pylori reinfection rate has varied in different countries due to socioeconomic and hygienic conditions. Helicobacter pylori monoresistance to clarithromycin, metronidazole or levofloxacin was common in most countries. However, the prevalence of amoxicillin and tetracycline resistance has remained low. Because H. pylori infection and reinfection present serious challenges and because H. pylori resistance to clarithromycin, metronidazole or levofloxacin remains high in most countries, the selection of an efficient regimen to eradicate H. pylori is critical. Currently, bismuth-containing quadruple therapies still achieve high eradication rates. Moreover, susceptibility-based therapies are alternatives because they may avoid the use of unnecessary antibiotics. Novel regimens, e.g., vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, require further studies concerning their efficiency and safety for treating H. pylori.

Primary Antibiotic Resistance of Helicobacter pylori in China

BACKGROUND AND AIMS

Antibiotic resistance is the most important factor leading to the failure of eradication regimens; thus, it is important to obtain regional antibiotic resistance information. This review focuses on the prevalence of Helicobacter pylori primary resistance to clarithromycin, metronidazole, amoxicillin, levofloxacin, tetracycline, and furazolidone in China.

METHODS

We searched the PubMed, EMBASE, the China National Knowledge Infrastructure, and Chinese Biomedical databases from the earliest date of each database to October 2016. The search terms included the following: H. pylori, antibiotic (including clarithromycin, metronidazole, amoxicillin, levofloxacin, tetracycline, and furazolidone) resistance with or without China or different regions of China. The data analysis was performed using MedCalc 15.2.2. Each article was weighted according to the number of isolated H. pylori strains. A pooled proportion analysis was performed.

RESULTS

Twenty-three studies (14 studies in English and 9 in Chinese) were included in this review. A total of 6274, 6418, 3921, 5468, 2802, and 275 H. pylori strains were included in this review to evaluate the prevalence of H. pylori primary resistance to clarithromycin, metronidazole, levofloxacin, amoxicillin, tetracycline, and furazolidone, respectively. Overall, the primary resistance rates of clarithromycin, metronidazole, levofloxacin, amoxicillin, tetracycline, and furazolidone were 28.9, 63.8, 28.0, 3.1, 3.9, and 1.7%, respectively.

CONCLUSIONS

In China, the prevalence of H. pylori primary resistance to clarithromycin, metronidazole, and levofloxacin was high and increased over time, whereas the resistance rates to amoxicillin, tetracycline, and furazolidone were low and stable over time.

New opportunities for the prevention of gastric cancer

The approvals and provisions of the Management of Helicobacter pylori infection-the Maastricht V/ Florence Consensus Report and those of the Kyoto Global Consensus Conference on H. pylori-associated gastritis, concerning with the primary and secondary prevention of gastric cancer (GC), unambiguously suggest that H. pylori infection is the most important risk factor of GC. Accordingly, the basis for the primary and secondary prevention of GC is the optimization of H. pylori eradication therapy. The clear direct relationship of the risk of GC to the severity and extent of atrophic gastritis, intestinal metaplasia and dysplasia and no reversal of intestinal metaplasia and dysplasia in the presence of H. pylori eradication presume that gastroprotective agents should be used for primary and secondary prevention. Experimental and clinical findings can lead to the conclusion that rebamipide is a highly effective and safe agent for the primary and secondary prevention of GC in patients with and without H. pylori infection, by optimizing anti-Helicobacter therapy, its anti-inflammatory effect and ability to restore the cellular structure of the gastric epithelium.

Polaprezinc combined with clarithromycin-based triple therapy for Helicobacter pylori-associated gastritis: A prospective, multicenter, randomized clinical trial

The efficacy and safety of polaprezinc combined with triple therapy was compared with triple therapy alone in the eradication of Helicobacter pylori. A randomized, parallel-group, open-label, controlled, prospective multicenter study was conducted in 11 cities in China. Treatment-naive patients with H. pylori-associated gastritis were randomly assigned to one of three arms for a 14-day treatment: Arm A triple therapy (omeprazole 20 mg, amoxicillin 1 g, and clarithromycin 500 mg, each twice daily) plus polaprezinc 75 mg twice daily; Arm B triple therapy plus polaprezinc 150 mg twice daily, or Arm C triple therapy alone. The rate of H. pylori eradication was the primary endpoint. Secondary endpoints were symptom improvement and lower incidence of adverse events. 303 patients completed the study- 106, 96, and 101 patients in Arms A, B, and C, respectively. Intention-to-treat (ITT) analysis showed that the rate of H. pylori eradication was significantly higher for Arms A (77.0%) and B (75.9%) compared to Arm C (58.6%) (P < 0.01), whereas there was no difference between Arms A and B (P = 0.90). Per-protocol (PP) analysis showed that the rate of H. pylori eradication was significantly higher for Arms A (81.1%) and B (83.3%) compared to Arm C (61.4%) (P < 0.01), whereas there was no significant difference between Arms A and B (P = 0.62). All three groups reported significant symptom improvement at 7, 14, and 28 days after treatment, compared to baseline (P < 0.0001). The adverse event rate for Arm B (5.1%) was higher than for Arms A (2.8%) (P = 0.04) and C (1.9%) (P = 0.02). There were no serious adverse events in any group. It appears that standard dose polaprezinc combined with triple therapy can significantly improve the H. pylori eradication rate, without an increase in toxicity.

Transient receptor potential vanilloid 4 (TRPV4) silencing in Helicobacter pylori-infected human gastric epithelium

BACKGROUND

Helicobacter pylori (HP) infection induces methylation silencing of specific genes in gastric epithelium. Various stimuli activate the nonselective cation channel TRPV4, which is expressed in gastric epithelium where it detects mechanical stimuli and promotes ATP release. As CpG islands in TRPV4 are methylated in HP-infected gastric epithelium, we evaluated HP infection-dependent changes in TRPV4 expression in gastric epithelium.

MATERIALS AND METHODS

Human gastric biopsy samples, a human gastric cancer cell line (AGS), and a normal gastric epithelial cell line (GES-1) were used to detect TRPV4 mRNA and protein expression by RT-PCR and Western blotting, respectively. Ca²⁺ imaging was used to evaluate TRPV4 ion channel activity. TRPV4 methylation status was assessed by methylation-specific PCR (MSP). ATP release was measured by a luciferin-luciferase assay.

RESULTS

TRPV4 mRNA and protein were detected in human gastric biopsy samples and in GES-1 cells. MSP and demethylation assays showed TRPV4 methylation silencing in AGS cells. HP coculture directly induced methylation silencing of TRPV4 in GES-1 cells. In human samples, HP infection was associated with TRPV4 methylation silencing that recovered after HP eradication in a time-dependent manner.

CONCLUSION

HP infection-dependent DNA methylation suppressed TRPV4 expression in human gastric epithelia, suggesting that TRPV4 methylation may be involved in HP-associated dyspepsia.

The Gastric Microbiome and Its Influence on Gastric Carcinogenesis: Current Knowledge and Ongoing Research

Gastric malignancies are a leading cause of cancer-related death worldwide. At least 2 microbial species are currently linked to carcinogenesis and the development of cancer within the human stomach. These include the bacterium Helicobacter pylori and the Epstein-Barr virus. In recent years, there has been increasing evidence that within the human gastrointestinal tract it is not only pathogenic microbes that impact human health but also the corresponding autochthonous microbial communities. This article reviews the gastrointestinal microbiome as it relates primarily to mechanisms of disease and carcinogenesis within the upper gastrointestinal tract.

Epidemiology, clinical impacts and current clinical management of Helicobacter pylori infection

Helicobacter pylori infection is a major cause of morbidity and mortality worldwide. More than 50% of the global population is estimated to be infected. Differences in prevalence exist within and between countries, with higher prevalence seen among people with lower socio-economic status. Most transmission of infection occurs early in life, predominantly from person to person in the family setting. H. pylori is the cause of most peptic ulcer disease, gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and causes symptoms in a subset of patients with functional dyspepsia. Choice of diagnostic test depends on the clinical context; urea breath tests and endoscopy with biopsy are the major diagnostic tools. Evidence-based indications for eradication of H. pylori infection are well documented. The most widely used and recommended eradication therapy in Australia is triple therapy comprising a proton pump inhibitor, amoxycillin and clarithromycin, usually for 1 week. Effective alternative regimens are available for patients with proven allergy to penicillin. Antimicrobial resistance is the major determinant of the outcome of eradication therapy. Trends in antibiotic resistance need to be monitored locally, but individual patient susceptibility testing is not usually necessary as it rarely guides the choice of therapy. The outcome of treatment should be assessed not less than 4 weeks after therapy. This is usually done with a urea breath test if follow-up endoscopy is not required. When first-line therapy fails, several proven second-line therapies may be used. Repeat first-line therapy and ad hoc regimens should be avoided. Overall cumulative eradication rates should approach 99%.

Serum Level of Trefoil Factor 2 can Predict the Extent of Gastric Spasmolytic Polypeptide-Expressing Metaplasia in the H. pylori-Infected Gastric Cancer Relatives

BACKGROUND & AIMS

Gastric cancer has familial clustering in incidence, and the familial relatives of gastric cancer sufferers are prone to have spasmolytic polypeptide-expressing metaplasia (SPEM), and intestinal metaplasia (IM) after H. pylori infection. This study tested whether serum pepsinogen I/II and trefoil factor family (TFF) proteins can predict SPEM or IM in the H. pylori-infected relatives of patients with gastric cancer.

METHODS

We prospectively enrolled 119 H. pylori-infected relatives of gastric cancer patients of noncardiac gastric cancer patients, who then received panendoscopy to obtain gastric biopsy to define the presence of corpus gastritis index (CGI), SPEM, and IM. The advanced SPEM in histology was defined by TFF2 immunohistochemistry. Each patient also had checkups of serum TFF2, TFF3, and pepsinogen I/II by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The 119 H. pylori-infected relatives included 61 with SPEM, and 34 with IM. The presence of either IM or SPEM was not related to the serum TFF2, TFF3, and pepsinogen I/II levels (p > .05). Serum TFF2 levels were higher in relatives with CGI who also had advanced SPEM (p = .032). For relatives without CGI, the elevated serum TFF2 levels correlated with higher H. pylori density and more severe gastritis in antrum (p = .001).

CONCLUSION

The serum TFF2 level cannot predict SPEM or IM in H. pylori-infected relatives of patients with gastric cancer. For H. pylori-infected relatives with CGI, serum TFF2 levels may predict the advanced severity of SPEM. Elevated serum TFF2 levels may indicate severe H. pylori-related inflammation, at risk of development or progression of SPEM in relatives without CGI.

The internalization of Helicobacter pylori plays a role in the failure of H. pylori eradication

BACKGROUND

Helicobacter pylori (H. pylori) internalization involves invasion of cells by the bacterium. Several studies have shown that H. pylori can invade human gastric epithelial cells, immune cells, and Candida yeast in vivo and in vitro. Whether bacterial invasion plays a role in eradication failure is unclear.

AIM

To investigate the relationship between H. pylori invasion of GES-1 cells and H. pylori eradication failure.

MATERIALS AND METHODS

Forty-two clinical strains isolated from H. pylori-positive patients with different outcomes after treatment with furazolidone-based therapy were examined (17 failures and 25 successes). The H. pylori strains were shown to be susceptible to amoxicillin and furazolidone, and the patients also exhibited good compliance. Genotyping was performed for cagA and vacA (s and m). The antibiotic susceptibility of the strains to amoxicillin, furazolidone, clarithromycin, metronidazole, and levofloxacin was determined by E-tests. The levels of H. pylori invasion of GES-1 cells were detected by gentamicin colony-forming unit assays.

RESULTS

The internalization level in the eradication success group was 5.40±5.78 × 10^-3  cfu/cell, and the median was 6.194 × 10^-3  cfu/cell; the internalization level in the eradication failure group was 8.98±5.40 × 10^-3  cfu/cell, and the median was 10.28 × 10^-3  cfu/cell. The eradication failure group showed a greater invasion level than the eradication success group (P<.05). No significant difference was observed between the susceptible strains and the resistant strains when the internalization levels were compared (P>.05).

CONCLUSIONS

The results showed that H. pylori invasion of the gastric epithelia might play a role in eradication failure.

Role of the Mdm2 SNIP 309 Polymorphism in Gastric Mucosal Morphologic Patterns of Patients with Helicobacter pylori Associated Gastritis

BACKGROUND

The tumor suppressor p53 is as a regulator of cell proliferation, apoptosis and many other biological processes as well as external and internal stress responses. Mdm2 SNIP309 is a negative regulator of 53. Therefore, this study aimed to determine the role of the Mdm2 SNIP 309 polymorphism in the gastric mucosal morphological patterns in patients with Helicobacter pylori associated gastritis.

MATERIALS AND METHODS

A prospective cross-sectional study was carried out from November 2014 through November 2015. Biopsy specimens were obtained from patients and infection was proven by positive histology. Gastric mucosa specimens were sent to the Molecular Genetics Unit, Institute of Medicine, Suranaree University of Technology where they were tested by molecular methods to detect the patterns of Mdm2 SNIP 309 polymorphism using the real-time PCR hybridization probe method. The results were analyzed and correlated with gastric mucosal morphological patterns by using C-NBI endoscopy.

RESULTS

A total of 300 infected patients were enrolled and gastric mucosa specimens were collected. In this study the percentage of Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygous was 78% and 19 % respectively whereas Mdm2 SNIP309 G/G homozygous was 3%. Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygosity correlated with type 1 to type 3 gastric mucosal morphological patterns (P<0.01) whereas Mdm2 SNIP309 G/G homozygous correlated with type 4 and type 5 (P<0.01).

CONCLUSIONS

Our study finds the frequency of Mdm2 SNIP309 G/G in a Thai population is very low, and suggests that this can explain ae Thailand enigma. Types 1 to type 3 are the most common gastric mucosal morphological patterns according to the unique genetic polymorphism of MDM2 SNIP 309 in the Thai population.

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

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

Functional dyspepsia susceptibility is related to CD14, GNB3, MIF, and TRPV1 gene polymorphisms in the Greek population

BACKGROUND

Functional dyspepsia (FD) susceptibility might be influenced by polymorphisms of genes related to inflammation (CD14, macrophage migration inhibitory factor [MIF]), motor (GNB3), and sensory dysfunction (GNB3, TRPV1). We examined the association between CD14 rs2569190, GNB3 rs5443, MIF rs222747, and TRPV1 rs755622 gene polymorphisms with FD (Rome III criteria) in the Greek population.

METHODS

We genotyped 174 dyspeptics (115 with epigastric pain syndrome; 41% Helicobacter pylori positive) and 181 controls using polymerase chain reaction-based methods and we measured disease symptoms' burden with a modified Gastrointestinal Symptoms Related Scale.

KEY RESULTS

Homozygous for the TT genotype and the T allele of the CD14 gene were significantly associated (OR [95% CI]) with FD (2.65 [1.42-4.94] and 1.67 [1.23-2.26], respectively). The CT, TT genotypes, and T allele frequencies of GNB3 showed also significant association with FD (2.18 [1.35-3.54], 3.46 [1.30-9.23], and 2.18 [1.48-3.19]). While heterozygous GC MIF genotype was more common in dyspeptics (1.67 [1.07-2.60]), homozygous CC genotype and the C allele of TRPV1 gene were more prevalent in controls (0.47 [0.25-0.87] and 0.69 [0.51-0.92], respectively). None of the gene polymorphism was related either to dyspepsia clinical syndrome type or to the H. pylori infection. Among dyspeptics, CD14 TT genotype was related to lower epigastric pain burden score (p<.011); CD14 CT genotype was related to higher epigastric burning and nausea burden scores (p<.04) while belching score was lower (p=.027) in MIF CG dyspeptics.

CONCLUSION & INFERENCES

Functional dyspepsia susceptibility is related to CD14, GNB3, MIF, and TRPV1 gene polymorphisms, while CD14 and MIF gene variants are also associated with dyspepsia symptoms burden.

[Possibilities for optimization of eradication therapy for Helicobacter pylori infection in modern clinical practice]

A steady decline in the effectiveness of standard eradication therapy (ET) regimens for Helicobacter pylori infection necessitates a search for ways of their optimization, by enhancing the efficiency of treatment protocols and by improving their safety and tolerability. The review systematizes the data available in the literature on main accessible methods for optimizing ET regimens. Among the optimization methods that can considerably enhance the efficiency of ET regimens, one may identify their addition of a bismuth agent (by 10-20%), the use of rebamipide (by 11.9%), adjuvant therapy with probiotics (by 8.1-13%), or double-dose proton pump inhibitors (by 8%). Only adjuvant therapy with probiotics results in a significant decrease in the incidence of side effects from ET. In posteradication period, rebamipide should be used to potentiate gastric mucosal repair and to regress inflammatory processes.

Optimized high-dose amoxicillin-proton-pump inhibitor dual therapies fail to achieve high cure rates in China

Background\Aim: Quadruple daily administration of proton-pump inhibitor (PPI) therapy achieves potent acid inhibition, and combined with amoxicillin, with its pharmacodynamic and pharmacokinetic characteristics, may be efficient for Helicobacter pylori eradication. We compared the efficacy of two optimized high-dose dual therapies with a bismuth-containing quadruple regimen for treating H. pylori infection. Rabeprazole dosages for H. pylori eradication were also evaluated.

PATIENTS AND METHODS

Treatment-naive and H. pylori-positive subjects were recruited and randomly apportioned to three treatment groups: Group A (n = 87), rabeprazole 10 mg plus amoxicillin 750 mg (4 times/day for 14 days); Group B (n = 87), rabeprazole 20 mg plus amoxicillin 750 mg (4 times/day for 14 days); and Group C (n = 89), bismuth-containing quadruple regimen consisting of rabeprazole 20 mg, bismuth 220 mg, amoxicillin 1000 mg, and clarithromycin 500 mg (2 times/day for 14 days). Four weeks after treatment discontinuation, patients were examined for H. pylori infection by 13C-urea breath test. The rates of adverse effects, compliance, and eradication were evaluated.

RESULTS

Eradication rates in groups A, B, and C were 78.1, 81.6, and 84.3%, respectively, based on intention-to-treat analysis, or 79.1, 83.5, and 86.2%, according to per-protocol analysis. Rates of adverse events and compliance of the three groups were similar.

CONCLUSION

For treating H. pylori infection, optimized high-dose amoxicillin-PPI dual therapies failed to achieve high cure rates in China and held no advantage over a bismuth-containing quadruple regimen.

[Molecular genetic predictors of resistance to anti-Helicobacter pylori therapy]

In current clinical practice, there is no optimal empirical therapy for Helicobacter pylori (H. pylori) infection and there is a progressive decrease in the efficiency of classical eradication therapy (ET) regimens. The variability in the efficiency of ET in a specific patient is largely due to the heterogeneous molecular genetic mechanisms underlying the resistance of the microorganism to the components of the treatment regimens. The basis of the mechanisms for antibiotic resistance in H. pylori is mainly the point mutations in some genes, which determine alterations in the mechanisms of action of drugs, such as clarithromycin (domain V of 23S rRNA), metronidazole (rdxA, frxA), amoxicillin (pbp1A), tetracycline (16S rRNA), and levofloxacin (gyrA). The predictors of resistance to ET are also the CagA-negative status of the microorganism and the presence of the vacA s2 allele. There are a number of host genetic determinants (the CYP2C19 genotype (*1/*1, *1/*17, *17/*17) and the MDR1 3435 T/T genotype (in an Asian population)) that reduce the efficiency of ET, by altering the pharmacokinetics of proton pump inhibitors. In addition, the IL-1β-511 C/C polymorphism that affects gastric acid secretion is a predictor of the inefficiency of ET.

The Role of Duodenal Inflammation in Functional Dyspepsia

Functional dyspepsia (FD) is common and significantly impairs quality of life. Symptoms of FD are considered to originate from the gastroduodenal region, classified by the Rome criteria as disorders of brain-gut interaction without structural alteration. However, it is now apparent that FD is a number of syndromes, the epigastric pain syndrome (bothersome epigastric pain or epigastric burning) and the postprandial distress syndrome (with bothersome postprandial fullness or early satiation) and there are wide-ranging symptoms and severity. The origin of these troublesome symptoms is now considered to be a result of disrupted gastroduodenal neuropathophysiology. The complexity of the syndrome indicates that there must be different triggers, supported by the limited efficacy of the many treatments available. Current research based on evidence by association suggests that duodenal contents, including the duodenal microbiome, pathogens, and allergy may be triggers of FD. Recent studies have also shown that systemic responses of increased circulating lymphocytes and elevated proinflammatory cytokines and subtle inflammation in the duodenum may accompany the onset and persistence of symptoms. This inflammatory phenotype is characterized by innate inflammation, an eosinophil infiltrate in the duodenum in FD in those with postprandial distress syndrome. Routine histopathology practice does not quantify these cells so the status of FD is not yet appreciated as an inflammatory condition. Thus functional is becoming inflammatory and this breakthrough in understanding that functional does not necessarily mean no, but subtle pathology, may improve therapeutic options, which are currently aimed at symptom relief rather than targeted at underlying pathology.

The Effects of Synbiotic "Bifidobacterium lactis B94 plus Inulin" Addition on Standard Triple Therapy of Helicobacter pylori Eradication in Children

AIM

The aim of this study is to evaluate the effects of the synbiotic Bifidobacterium lactis B94 plus inulin addition to the standard triple therapy on Helicobacter pylori (H. pylori) infection eradication rates.

METHODS

Children aged 6-16 years who had biopsy proven H. pylori infection were randomly classified into two groups. The first group received the standard triple therapy consisting of amoxicillin + clarithromycin + omeprazole. The second group was treated with the standard triple therapy and Bifidobacterium lactis B94 (5 × 10⁹ CFU/dose) plus inulin (900 mg) for 14 days, concurrently. Eradication was determined by ¹⁴C-urea breath test 4-6 weeks after therapy discontinuation.

RESULTS

From a total of 69 H. pylori infected children (F/M = 36/33; mean ± SD = 11.2 ± 3.0 years), eradication was achieved in 20/34 participants in the standard therapy group and 27/35 participants in the synbiotic group. The eradication rates were not significantly different between the standard therapy and the synbiotic groups [intent-to-treat, 58.8% and 77.1%, resp., p = 0.16; per-protocol, 64.5% and 81.8%, resp., p = 0.19]. There was no difference between the groups in terms of symptom relief (p = 0.193). The reported side effects were ignorable.

CONCLUSION

Considering the eradication rates, synbiotic addition to therapy showed no superiority over the standard triple therapy conducted alone. This trial is registered with NCT03165253.

Helicobacter pylori screening: options and challenges

Helicobacter pylori gastritis is the most frequent infectious disease in the gastrointestinal tract. Clinical sequelae of the infection including peptic ulcer disease, sporadic gastric cancer (GC) and primary B-cell gastric lymphoma (MALT-lymphoma) may develop in up to 20% of the infected individuals. The H. pylori screen-and-treat strategy is addressed to members of communities with high GC incidence, and first-degree relatives of GC patients. For primary GC prevention, H. pylori screen-and-treat is most effective in patients without precancerous conditions. In populations at moderate risk, strategies for GC prevention need to be explored. A special clinical scenario for primary and secondary prevention of H. pylori related benign complications are patients on non-steroidal anti-inflammatory drugs and low-dose aspirin. Vaccination represents another option for eliminating H. pylori infection in the population and a new H. pylori vaccine has shown promising results. However, long-term effects with the use of vaccine are not available.

Surveillance of Helicobacter pylori Antibiotic Susceptibility in Indonesia: Different Resistance Types among Regions and with Novel Genetic Mutations

Information regarding Helicobacter pylori antibiotic resistance in Indonesia was previously inadequate. We assessed antibiotic susceptibility for H. pylori in Indonesia, and determined the association between virulence genes or genetic mutations and antibiotic resistance. We recruited 849 dyspeptic patients who underwent endoscopy in 11 cities in Indonesia. E-test was used to determine the minimum inhibitory concentration of five antibiotics. PCR-based sequencing assessed mutations in 23S rRNA, rdxA, gyrA, gyrB, and virulence genes. Next generation sequencing was used to obtain full-length sequences of 23S rRNA, infB, and rpl22. We cultured 77 strains and identified 9.1% with clarithromycin resistance. Low prevalence was also found for amoxicillin and tetracycline resistance (5.2% and 2.6%, respectively). In contrast, high resistance rates to metronidazole (46.7%) and levofloxacin (31.2%) were demonstrated. Strains isolated from Sumatera Island had significantly higher metronidazole resistance than those from other locations. Metronidazole resistant strains had highly distributed rdxA amino acid substitutions and the 23S rRNA A2143G mutation was associated with clarithromycin resistance (42.9%). However, one strain with the highest MIC value had a novel mutation in rpl22 without an A2143G mutation. Mutation at Asn-87 and/or Asp-91 of gyrA was associated with levofloxacin-resistance and was related to gyrB mutations. In conclusions, although this is a pilot study for a larger survey, our current data show that Indonesian strains had the high prevalence of metronidazole and levofloxacin resistance with low prevalence of clarithromycin, amoxicillin, and tetracycline resistance. Nevertheless, clarithromycin- or metronidazole-based triple therapy should be administered with caution in some regions of Indonesia.

Current status of Helicobacter pylori infection and evolution of treatment strategy in China

Infection with Helicobacter pylori (H. pylori) has become a common digestive disease and the prevalence of H. pylori infection remains high in the Chinese population. Recently, the Kyoto global consensus report on H. pylori gastritis and the Toronto consensus for the treatment of H. pylori infection in adults were issued. Therefore, it is essential to discuss the prevention and control of H. pylori infection in China. Due to severe resistance to antibiotics, toxic and host factors, the eradication rate in China has currently became lower than before. Therefore, whether to intervene H. pylori infection in the asymptomatic population and enlarge the indication for eradication and the cost-effect for this new strategy should be discussed. In addition, the implementation of the "test and treat" policy or not in China is debatable. Developing optimal treatment strategy has become a major challenge that clinicians face. This review focuses on the current H. pylori infection situation and the evolution of treatment strategies in China.

Effective and safe proton pump inhibitor therapy in acid-related diseases - A position paper addressing benefits and potential harms of acid suppression

BACKGROUND

The introduction of proton pump inhibitors (PPIs) into clinical practice has revolutionized the management of acid-related diseases. Studies in primary care and emergency settings suggest that PPIs are frequently prescribed for inappropriate indications or for indications where their use offers little benefit. Inappropriate PPI use is a matter of great concern, especially in the elderly, who are often affected by multiple comorbidities and are taking multiple medications, and are thus at an increased risk of long-term PPI-related adverse outcomes as well as drug-to-drug interactions. Herein, we aim to review the current literature on PPI use and develop a position paper addressing the benefits and potential harms of acid suppression with the purpose of providing evidence-based guidelines on the appropriate use of these medications.

METHODS

The topics, identified by a Scientific Committee, were assigned to experts selected by three Italian Scientific Societies, who independently performed a systematic search of the relevant literature using Medline/PubMed, Embase, and the Cochrane databases. Search outputs were distilled, paying more attention to systematic reviews and meta-analyses (where available) representing the best evidence. The draft prepared on each topic was circulated amongst all the members of the Scientific Committee. Each expert then provided her/his input to the writing, suggesting changes and the inclusion of new material and/or additional relevant references. The global recommendations were then thoroughly discussed in a specific meeting, refined with regard to both content and wording, and approved to obtain a summary of current evidence.

RESULTS

Twenty-five years after their introduction into clinical practice, PPIs remain the mainstay of the treatment of acid-related diseases, where their use in gastroesophageal reflux disease, eosinophilic esophagitis, Helicobacter pylori infection, peptic ulcer disease and bleeding as well as, and Zollinger-Ellison syndrome is appropriate. Prevention of gastroduodenal mucosal lesions (and symptoms) in patients taking non-steroidal anti-inflammatory drugs (NSAIDs) or antiplatelet therapies and carrying gastrointestinal risk factors also represents an appropriate indication. On the contrary, steroid use does not need any gastroprotection, unless combined with NSAID therapy. In dyspeptic patients with persisting symptoms, despite successful H. pylori eradication, short-term PPI treatment could be attempted. Finally, addition of PPIs to pancreatic enzyme replacement therapy in patients with refractory steatorrhea may be worthwhile.

CONCLUSIONS

Overall, PPIs are irreplaceable drugs in the management of acid-related diseases. However, PPI treatment, as any kind of drug therapy, is not without risk of adverse effects. The overall benefits of therapy and improvement in quality of life significantly outweigh potential harms in most patients, but those without clear clinical indication are only exposed to the risks of PPI prescription. Adhering with evidence-based guidelines represents the only rational approach to effective and safe PPI therapy. Please see related Commentary: doi: 10.1186/s12916-016-0724-1 .

Functional dyspepsia

PURPOSE OF REVIEW

Functional dyspepsia affects 10% of the population. Emerging data are beginning to unravel the pathogenesis of this heterogeneous disorder, and new data on treatment are helping to guide evidence-based practice. In this review, the latest advances are summarized and discussed.

RECENT FINDINGS

The Rome IV criteria were published in 2016 and are similar to Rome III but further emphasize the subtypes (postprandial distress syndrome and epigastric pain syndrome) rather than focussing on the syndrome as a whole, and conclude that gastroesophageal reflux disease and irritable bowel syndrome are part of the functional dyspepsia spectrum. Environment is dominant in the pathogenesis. New data implicate herbivore pets and antibiotic exposure for a nongastrointestinal infection but require confirmation. Further experimental data suggest duodenal eosinophils and mast cells can alter enteric neuronal structure and function in functional dyspepsia.

SUMMARY

Advances in our understanding of functional dyspepsia are changing clinical practice.

Gastric precancerous conditions and Helicobacter pylori infection in dyspeptic patients with or without endoscopic lesions

OBJECTIVE

In dyspeptic patients, esophagogastroduodenoscopy is often negative for visible lesions. Biopsies of the normal-appearing mucosa for Helicobacter pylori detection are not routinely obtained. Diagnostic gain of routine biopsies is still debated. This study aimed to assess the occurrence of H. pylori infection and related gastric premalignant conditions in dyspeptic patients without visible lesions at esophagogastroduodenoscopy and whether the presence/absence of endoscopically visible lesions may address the endoscopist to obtain gastric biopsies.

MATERIALS AND METHODS

Post hoc study on endoscopic-histological data from 589 patients with dyspepsia (median age 57 years) obtained during a prospective nationwide study. Patients with dyspepsia as indication for esophagogastroduodenoscopy, never treated for H. pylori, were included. All the patients underwent esophagogastroduodenoscopy with biopsies according to Sydney system. Clinical data were collected using a structured questionnaire.

RESULTS

In 66.4% patients, the gastricduodenal mucosa appeared normal at esophagogastroduodenoscopy. In patients with or without visible lesions at esophagogastroduodenoscopy, H. pylori infection (51.5% vs. 50.1%, p = 0.82) and atrophic-metaplastic gastritis (33.3% vs. 27.6%, p = 0.18) were similar. Endoscopically visible lesions were poor predictors for H. pylori infection or gastric precancerous conditions showing positive and negative predictive values of 51.5% and 49.8% for H. pylori and 33.3% and 72.3% for atrophic-metaplastic gastritis. At logistic regression, the presence of H. pylori infection showed a negative association with ongoing antisecretory treatment (OR: 0.67), the presence of visible gastroduodenal lesions was not associated.

CONCLUSIONS

Dyspeptic patients with or without visible endoscopic lesions had the same occurrence of H. pylori infection and related premalignant conditions, which might be missed without biopsies, in particular, in patients on anti-secretory treatment.

Usefulness of Endoscopic Imaging to Visualize Regional Alterations in Acid Secretion of Noncancerous Gastric Mucosa after Helicobacter pylori Eradication

Purpose

Endoscopic diagnosis of gastric cancer (GC) that emerges after eradication of Helicobacter pylori may be affected by unique morphological changes. Using comprehensive endoscopic imaging, which can reveal biological alterations in gastric mucosa after eradication, previous studies demonstrated that Congo red chromoendoscopy (CRE) might clearly show an acid non-secretory area (ANA) with malignant potential, while autofluorescence imaging (AFI) without drug injection or dyeing may achieve early detection or prediction of GC. We aimed to determine whether AFI might be an alternative to CRE for identification of high-risk areas of gastric carcinogenesis after eradication.

Materials and Methods

We included 27 sequential patients with metachronous GC detected during endoscopic surveillance for a mean of 82.8 months after curative endoscopic resection for primary GC and eradication. After their H. pylori infection status was evaluated by clinical interviews and ¹³C-urea breath tests, the consistency in the extension of corpus atrophy (e.g., open-type or closed-type atrophy) between AFI and CRE was investigated as a primary endpoint.

Results

Inconsistencies in atrophic extension between AFI and CRE were observed in 6 of 27 patients, although CRE revealed all GC cases in the ANA. Interobserver and intraobserver agreements in the evaluation of atrophic extension by AFI were significantly less than those for CRE.

Conclusions

We demonstrated that AFI findings might be less reliable for the evaluation of gastric mucosa with malignant potential after eradication than CRE findings. Therefore, special attention should be paid when we clinically evaluate AFI findings of background gastric mucosa after eradication (University Hospital Medical Information Network Center registration number: UMIN000020849).

Improved Detection of Helicobacter pylori Infection and Premalignant Gastric Mucosa Using "Site Specific Biopsy": a Randomized Control Clinical Trial

BACKGROUND

Helicobacter pylori infection and premalignant gastric mucosa can be reliably identified using conventional narrow band imaging (C-NBI) gastroscopy. The aim of our study was to compare standard biopsy with site specific biopsy for diagnosis of H. pylori infection and premalignant gastric mucosa in daily clinical practice.

MATERIALS AND METHODS

Of a total of 500 patients who underwent gastroscopy for investigation of dyspeptic symptoms, 250 patients underwent site specific biopsy using C-NBI (Group 1) and 250 standard biopsy (Group 2). Sensitivity, specificity, and positive and negative predictive values were assessed. The efficacy of detecting H. pylori associated gastritis and premalignant gastric mucosa according to the updated Sydney classification was also compared.

RESULTS

In group 1 the sensitivity, specificity, positive and negative predictive values for predicting H. pylori positivity were 95.4%, 97.3%, 98.8% and 90.0% respectively, compared to 92.9%, 88.6%, 83.2% and 76.1% in group 2. Site specific biopsy was more effective than standard biopsy in terms of both H. pylori infection status and premalignant gastric mucosa detection (P<0.01).

CONCLUSIONS

Site specific biopsy using C-NBI can improve detection of H. pylori infection and premalignant gastric mucosa in daily clinical practice.