Helicobacter pylori eradication rates with concomitant and tailored therapy based on 23S rRNA point mutation: A multicenter randomized controlled trial

Rapid diagnosis and precision treatment of Helicobacter pylori infection in clinical settings

Helicobacter pylori is a gram-negative bacterium that colonizes the stomach of approximately half of the worldwide population, with higher prevalence in densely populated areas like Asia, the Caribbean, Latin America, and Africa. H. pylori infections range from asymptomatic cases to potentially fatal diseases, including peptic ulcers, chronic gastritis, and stomach adenocarcinoma. The management of these conditions has become more difficult due to the rising prevalence of drug-resistant H. pylori infections, which ultimately lead to gastric cancer and mucosa-associated lymphoid tissue (MALT) lymphoma. In 1994, the International Agency for Research on Cancer (IARC) categorized H. pylori as a Group I carcinogen, contributing to approximately 780,000 cancer cases annually. Antibiotic resistance against drugs used to treat H. pylori infections ranges between 15% and 50% worldwide, with Asian countries having exceptionally high rates. This review systematically examines the impacts of H. pylori infection, the increasing prevalence of antibiotic resistance, and the urgent need for accurate diagnosis and precision treatment. The present status of precision treatment strategies and prospective approaches for eradicating infections caused by antibiotic-resistant H. pylori will also be evaluated.

Culture-based susceptibility-guided tailored versus empirical concomitant therapy as first-line Helicobacter pylori treatment: A randomized clinical trial

BACKGROUND

With the increasing resistance to antimicrobial agents, susceptibility-guided tailored therapy has been emerging as an ideal strategy for Helicobacter pylori treatment. However, susceptibility-guided tailored therapy requires additional cost, time consumption, and invasive procedure (endoscopy) and its superiority over empirical quadruple therapy as the first-line H. pylori treatment remains unclear.

AIMS

To compare the efficacy of culture-based susceptibility-guided tailored versus empirical concomitant therapy as the first-line Helicobacter pylori treatment.

METHODS

This open-label, randomized trial was performed in four Korean institutions. A total of 312 Patients with H. pylori-positive culture test and naïve to treatment were randomly assigned in a 3:1 ratio to either culture-based susceptibility-guided tailored therapy (clarithromycin-based or metronidazole-based triple therapy for susceptible strains or bismuth quadruple therapy for dual-resistant strains, n = 234) or empirical concomitant therapy (n = 78) for 10 days. Eradication success was evaluated by 13C-urea breath test at least 4 weeks after treatment.

RESULTS

Prevalence of dual resistance to both clarithromycin and metronidazole was 8%. H. pylori eradication rates for tailored and concomitant groups were 84.2% and 83.3% by intention-to-treat analysis (p = 0.859), respectively, and 92.9% and 91.5% by per-protocol analysis, respectively (p = 0.702), which were comparable between the two groups. However, eradication rates for dual-resistant strains were significantly higher in the tailored group than in the concomitant group. All adverse events were grade 1 or 2 based on the Common Terminology Criteria for Adverse Events and the incidence was significantly lower in the tailored group. The proportion of patients discontinuing treatment for adverse events was comparable between the two groups (2.1% vs. 2.6%).

CONCLUSIONS

The culture-based susceptibility-guided tailored therapy failed to show superiority over the empirical concomitant therapy in terms of eradication rate. Based on these findings, the treatment choice in clinical practice would depend on the background rate of antimicrobial resistance, availability of resources and costs associated with culture and susceptibility testing.

Comparison of Helicobacter pylori eradication rates between 7 and 14 days of tailored therapy according to clarithromycin resistance test: A randomized, multicenter, non-inferiority study

BACKGROUND

Recently, a simple tailored therapy based on clarithromycin resistance has been implemented as Helicobacter pylori (H. pylori) eradication therapy. Nonetheless, despite the tailored therapy and frequent adverse events, studies on treatment period are lacking. This study aimed to compare the H. pylori eradication rates of 7-day and 14-day tailored therapy regimens according to clarithromycin resistance.

MATERIALS AND METHODS

This multicenter, prospective, randomized, noninferiority trial enrolled H. pylori-positive patients who were randomly assigned to 7-day and 14-day regimen groups, depending on the presence or absence of clarithromycin resistance by 23S rRNA gene point mutations. Standard triple therapy (STT) (20 mg rabeprazole, 1 g amoxicillin, and 500 mg clarithromycin twice daily) or bismuth quadruple therapy (BQT) (20 mg rabeprazole twice daily, 500 mg metronidazole thrice daily, 120 mg bismuth four times daily, and 500 mg tetracycline four times daily) was assigned by clarithromycin resistance. Eradication rates and adverse events were evaluated.

RESULTS

A total of 314 and 278 patients were included in the intention-to-treat (ITT) and per-protocol (PP) analyses, respectively; however, 31 patients were lost to follow-up, whereas five patients violated the protocol. Both the 7-day and 14-day regimens showed similar eradication rates in the ITT (7-day vs. 14-day: 78.3% vs. 78.3%, p > 0.99) and PP (87.9% vs. 89.1%, p = 0.851) analyses. Non-inferiority was confirmed (p < 0.025). A subgroup analysis according to clarithromycin resistance (clarithromycin resistance rate: 28.7%) revealed no significant difference in eradication rates between the 7-day and 14-day STT (90.0% vs. 90.1%, p > 0.99) and BQT (82.5% vs. 86.5%, p = 0.757). Furthermore, adverse events did not significantly differ between the two groups.

CONCLUSIONS

The 7-day triple and quadruple therapy according to clarithromycin resistance showed similar eradication rates, as compared to the 14-day therapy.

Detection of Clarithromycin Resistance in Helicobacter pylori Using MmaxSure™ H. pylori &amp; ClaR Assay

INTRODUCTION

Clarithromycin resistance is a crucial factor in the eradication of Helicobacter pylori. This study aimed to evaluate the performance of MmaxSure™ H. pylori & ClaR Assay (MmaxSure™) in the diagnosis and detection of clarithromycin resistance in H. pylori.

METHODS

Subjects who underwent esophagogastroduodenoscopy between April 2020 and October 2022 were enrolled. The diagnostic performances of MmaxSure™ and dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) were compared with the rapid urease test and culture. Secondary gene sequencing analysis was performed in discordant cases of PCR tests.

RESULTS

A total of 156 gastric biopsy samples were analyzed. In H. pylori detection, MmaxSure™ showed a 95.9% sensitivity (95% CI: 90.6-98.6), a 42.7% specificity (95% CI: 26.3-60.7), and a kappa value of 0.457. For the detection of A2143G mutation samples, MmaxSure™ showed a 91.2% sensitivity (95% CI: 76.3-98.1), a 93.4% specificity (95% CI: 87.5-97.1), and a kappa value of 0.804. There were a total of 10 discordant cases compared to gene sequencing in A2143G mutation detection for MmaxSure™.

CONCLUSION

In this study, MmaxSure™ showed comparable diagnostic performance to DPO-PCR in the detection of the H. pylori and A2143G mutation. Further research is needed to confirm the clinical effectiveness of the MmaxSure™ assay in H. pylori eradication.

Efficacy of genotypic susceptibility-guided tailored therapy for Helicobacter pylori infection: A systematic review and single arm meta-analysis

BACKGROUND AND AIM

The prevalence of antibiotic resistance for Helicobacter pylori (H. pylori) has been increasing over the year, making it more difficult for traditional empirical therapy to successfully eradicate H. pylori. Thus, tailored therapy (TT) guided by molecular-based antibiotic susceptibility testing (AST) has been frequently recommended. We conducted a single-arm meta-analysis to determine the efficacy of tailored therapy guided by molecular-based AST.

METHODS

A systematic literature review was performed on multiple databases, and studies on molecular-based TT were included. The eradication rates of TT by intention-to-treat (ITT) and per-protocol (PP) analyses were pooled respectively.

RESULTS

A total of 35 studies from 31 literature (4626 patients) were included in the single-arm meta-analysis. Overall, the pooled eradication rate of TT was 86.9% (95% CI:84.7%-89.1%) by the ITT analysis, and 91.5% (95% CI:89.8%-93.2%) by PP analysis. The pooled eradication rates of first-line TT and rescue TT were 86.6% and 85.1% by ITT analysis and 92.0% and 87.9% by PP analysis, respectively. When tailored rescue therapy was based on the genotypic resistance to at least four antibiotics, the pooled eradication rates reached 89.4% by ITT analysis and 92.1% by PP analysis. For genotype-susceptive strains, the pooled eradication rate of TT with targeted antibiotics was 93.1% (95% CI:91.3%-94.9%), among which the pooled eradication rate of tailored bismuth quadruple therapy was the highest (94.3%). Besides, the eradication rate of 7-day TT or tailored triple therapy without bismuth for genotype-susceptive strains could both reach more than 93.0%.

CONCLUSION

Tailored therapy guided by molecular-based AST can achieve somewhat ideal therapeutic outcomes. TT with a 7-day duration or without bismuth for genotype-susceptible strains can achieve good eradication efficacy. The effectiveness of TT can be improved to some extent by expanding the coverage of AST or by adding bismuth.

Optimizing Helicobacter pylori Treatment: An Updated Review of Empirical and Susceptibility Test-Based Treatments

As the rate of discovery of drug-resistant Helicobacter pylori cases increases worldwide, the relevant societies have updated their guidelines for primary eradication regimens. A promising strategy against drug-resistant H. pylori is tailored therapy based on the results of an antibiotic susceptibility test; however, it is difficult to apply this strategy to all cases. Although culture-based antibiotic susceptibility tests can assess resistance to any antimicrobial agent, their greatest disadvantage is the time required to draw a conclusion. In contrast, molecular-based methods, such as polymerase chain reaction, can rapidly determine the presence of resistance, although a single test can only test for one type of antimicrobial agent. Additionally, the limited availability of facilities for molecular-based methods has hindered their widespread use. Therefore, low-cost, minimally invasive, simple, and effective primary regimens are needed. Several studies have compared the efficacy of the latest primary eradication regimens against that of tailored therapies, and their results have shaped guidelines. This article reviews the latest research on empirical and tailored treatments for H. pylori infections. Evidence for the superiority of tailored therapy over empirical therapy is still limited and varies by region and treatment regimen. A network meta-analysis comparing different empirical treatment regimens showed that vonoprazan triple therapy provides a superior eradication effect. Recently, favorable results towards vonoprazan dual therapy have been reported, as it reached eradication levels similar to those of vonoprazan triple therapy. Both vonoprazan dual therapy and tailored therapy based on antibiotic susceptibility tests could contribute to future treatment strategies.

Empirical versus tailored therapy based on genotypic resistance detection for Helicobacter pylori eradication: a systematic review and meta-analysis

Background

The eradication rate of Helicobacter pylori infection with empirical therapy has decreased due to increased drug resistance. The latest guidelines recommend genotypic resistance-guided therapy, but its clinical efficacy remains unclear.

Objectives

The purpose of our study was to evaluate whether tailored therapy based on genotypic resistance is superior to empirical therapy for H. pylori infection.

Design

A systematic review and meta-analysis of randomized controlled trials (RCTs) comparing tailored therapy based on genotypic resistance with empirical therapy was performed.

Sources and methods

We retrieved relevant studies from PubMed, Embase, and the Cochrane Library. The primary outcome was H. pylori eradication rate and the adverse events (AEs) was the secondary outcome. A random-effect model was applied to compare pooled risk ratios (RRs) with related 95% confidence intervals (CIs).

Results

A total of 12 qualified RCTs containing 3940 patients were identified in our systematic review and meta-analysis. The pooled eradication rates of tailored therapy based on the detection of genotypic resistance were consistently higher than those in the empirical treatment group, with no statistical significance. In triple therapy, the eradication rate was significantly higher in the tailored group than in the empirical group by intention-to-treat analysis (ITT) and per-protocol analysis (PP) analysis (p < 0.0001, RR: 1.20; 95% CI: 1.12-1.29; p < 0.0001, RR: 1.20; 95% CI: 1.15-1.25). In quadruple therapy, the eradication rate was higher in the empirical group (p = 0.001, RR: 0.93; 95% CI: 0.89-0.97; p = 0.009, RR: 0.95; 95% CI: 0.92-0.99). And this result was true for both bismuth quadruple therapy (BQT) and non-BQT. Regarding total AEs, the pooled rate was 34% in the tailored group and 37% in the empirical group, and no difference between the two groups was found (p = 0.17, RR: 0.88; 95% CI: 0.74-1.06).

Conclusion

In conclusion, tailored therapy based on molecular methods may offer better efficacy than empirical triple therapy, but it may not be superior to empirical quadruple therapy in eradicating H. pylori infection. Larger and more individualized RCTs are needed to aid clinical decision-making.

Registration PROSPERO

CRD42023408688.

Helicobacter pylori in the post-antibiotics era: from virulence factors to new drug targets and therapeutic agents

Helicobacter pylori is considered one of the most prevalent human pathogenic microbes globally. It is the main cause of a number of gastrointestinal ailments, including peptic and duodenal ulcers, and gastric tumors with high mortality rates. Thus, eradication of H. pylori is necessary to prevent gastric cancer. Still, the rise in antibiotic resistance is the most important challenge for eradication strategies. Better consideration of H. pylori virulence factors, pathogenesis, and resistance is required for better eradication rates and, thus, prevention of gastrointestinal malignancy. This article is aimed to show the role of virulence factors of H. pylori. Some are involved in its survival in the harsh environment of the human gastric lumen, and others are related to pathogenesis and the infection process. Furthermore, this work has highlighted the recent advancement in H. pylori treatment, as well as antibiotic resistance as a main challenge in H. pylori eradication. Also, we tried to provide an updated summary of the evolving H. pylori control strategies and the potential alternative drugs to fight this lethal resistant pathogen. Recent studies have focused on evaluating the efficacy of alternative regimens (such as sequential, hybrid, concomitant treatment, vonoprazan (VPZ)-based triple therapy, high-dose PPI-amoxicillin dual therapy, probiotics augmented triple therapy, or in combination with BQT) in the effective eradication of H. pylori. Thus, innovating new anti-H. pylori drugs and establishing H. pylori databanks are upcoming necessities in the near future.

Approaches for detection of antibiotic resistance of Helicobacter pylori: Recent research advances

Helicobacter pylori (H. pylori) infection, a contagious disease, has affected approximately half of the global population. It is associated with the occurrence and development of many diseases, which seriously endangers human public health. Antibiotics play an important role in H. pylori eradication therapy, and the common regimens for H. pylori eradication contain one to three antibiotics. Antibiotic resistance is one of the main reasons for the failure of H. pylori eradication. Detection of antibiotic resistance can be helpful for individualized management, reduction of drug resistance, and improvement of H. pylori eradication. Methods to detect antibiotic resistance of H. pylori primarily consist of traditional drug sensitivity tests and molecular biology methods, such as polymerase chain reaction and its related techniques, DNA sequencing, fluorescence in situ hybridization, and gene chip. This paper reviews the recent advances in approaches for detection of antibiotic resistance of H. pylori.

Antibiotic Resistance, Susceptibility Testing and Stewardship in Helicobacter pylori Infection

Despite the declining trend of Helicobacter pylori (H. pylori) prevalence around the globe, ongoing efforts are still needed to optimize current and future regimens in view of the increasing antibiotic resistance. The resistance of H. pylori to different antibiotics is caused by different molecular mechanisms, and advancements in sequencing technology have come a far way in broadening our understanding and in facilitating the testing of antibiotic susceptibility to H. pylori. In this literature review, we give an overview of the molecular mechanisms behind resistance, as well as discuss and compare different antibiotic susceptibility tests based on the latest research. We also discuss the principles of antibiotic stewardship and compare the performance of empirical therapies based on up-to-date resistance patterns and susceptibility-guided therapies in providing effective H. pylori treatment. Studies and clinical guidelines should ensure that the treatment being tested or recommended can reliably achieve a pre-agreed acceptable level of eradication rate and take into account the variations in antibiotic resistance across populations. Local, regional and international organizations must work together to establish routine antibiotic susceptibility surveillance programs and enforce antibiotic stewardship in the treatment of H. pylori, so that it can be managed in a sustainable and efficient manner.

Molecular testing-guided therapy versus susceptibility testing-guided therapy in first-line and third-line Helicobacter pylori eradication: two multicentre, open-label, randomised controlled, non-inferiority trials

BACKGROUND

Helicobacter pylori infection is an important causal factor of gastric cancer and peptic ulcer disease and is associated with immune thrombocytopenic purpura and functional dyspepsia. In H pylori strains, point mutations in the 23S rRNA and gyrA genes are associated with clarithromycin resistance and levofloxacin resistance, respectively. Whether the efficacy of molecular testing-guided therapy is non-inferior to that of susceptibility testing-guided therapy for H pylori eradication is unclear. Therefore, we aimed to compare the efficacy and safety of molecular testing-guided therapy and traditional culture-based susceptibility testing-guided therapy in first-line and third-line treatment of H pylori infection.

METHODS

We did two multicentre, open-label randomised trials in Taiwan. In trial 1 (done at seven hospitals), treatment-naive individuals infected with H pylori who were aged 20 years or older were eligible for study inclusion. In trial 2 (done at six hospitals), individuals aged 20 years or older who failed treatment after two or more eradication therapies for H pylori infection were eligible for enrolment. Eligible patients were randomly assigned (1:1) to receive either molecular testing-guided therapy or susceptibility testing-guided therapy. The randomisation sequence was generated by computer using permuted block randomisation with a block size of 4. All investigators were masked to the randomisation sequence. Clarithromycin and levofloxacin resistance were determined by agar dilution test for measuring minimum inhibitory concentrations in the susceptibility testing-guided therapy group, and by PCR and direct sequencing for detection of 23S rRNA and gyrA mutations in the molecular testing-guided therapy group. Study participants received clarithromycin sequential therapy, levofloxacin sequential therapy, or bismuth quadruple therapy according to the resistance status to clarithromycin and levofloxacin. The 13C-urease breath test was used to determine the status of H pylori infection at least 6 weeks after eradication therapy. The primary outcome was the eradication rate by intention-to-treat analysis. The frequency of adverse effects was analysed in patients with available data. The prespecified margins for non-inferiority were 5% for trial 1 and 10% for trial 2. The trials are ongoing for post-eradication follow-up and registered with ClinicalTrials.gov, NCT03556254 for trial 1, and NCT03555526 for trial 2.

FINDINGS

Between March 28, 2018, and April 23, 2021, 560 eligible treatment-naive patients with H pylori infection were recruited and randomly assigned to the molecular testing-guided therapy group or the susceptibility testing-guided therapy group in trial 1. Between Dec 28, 2017, and Oct 27, 2020, 320 eligible patients with refractory H pylori infection were recruited and randomly assigned to the molecular testing-guided therapy group or the susceptibility testing-guided therapy group in trial 2. 272 men and 288 women were recruited for trial 1, and 98 men and 222 women were recruited for trial 2. In first-line H pylori treatment, infection was eradicated in 241 (86%, 95% CI 82-90) of 280 patients in the molecular testing-guided therapy group and 243 (87%, 83-91) of 280 patients in the susceptibility testing-guided therapy group by intention-to-treat analysis (p=0·81). In third-line H pylori treatment, infection was eradicated in 141 (88%, 83-93) of 160 patients in the molecular testing-guided therapy group and 139 (87%, 82-92) of 160 patients in the susceptibility testing-guided therapy group by intention-to-treat analysis (p=0·74). The difference in the eradication rate between the molecular testing-guided therapy group and the susceptibility testing-guided therapy group was -0·7% (95% CI -6·4 to 5·0; non-inferiority p=0·071) in trial 1 and 1·3% (-6·0 to 8·5; non-inferiority p=0·0018 in trial 2 by intention-to-treat analysis. We found no difference in adverse effects across both treatment groups in trial 1 and trial 2.

INTERPRETATION

Molecular testing-guided therapy was similar to susceptibility testing-guided therapy in first-line therapy and non-inferior to susceptibility testing guided therapy in third-line treatment of H pylori infection, supporting the use of molecular testing-guided therapy for H pylori eradication.

FUNDING

Ministry of Science and Technology of Taiwan, and Centre of Precision Medicine of the Higher Education Sprout Project by the Ministry of Education of Taiwan.

Current role of tailored therapy in treating Helicobacter pylori infections. A systematic review, meta-analysis and critical analysis

BACKGROUND AND AIMS

Recent guidelines dictate that all Helicobacter pylori (H. pylori) infected subjects should receive curative therapy. The efficacy of empirical regimens for H. pylori eradication might decline with bacterial, drug, and host factors. The necessity of a tailored therapy still remains controversial. Here we provide a meta-analysis of the current status of susceptibility-based (tailored) therapy in which susceptibility-based therapies were compared to the currently accepted choice of empiric therapy. In this rapidly closing era, neither the susceptibility nor empiric therapies were routinely optimized, such that we report the outcome of comparisons on the efficacy of unoptimized tailored vs. locally preferred empiric treatments.

METHODS

PubMed, Medline, and Embase databases were searched using suitable keywords. Individual and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using the fixed- or random-effects model as appropriate. Heterogeneity was calculated employing the Cochrane Q test and I² values, whereas the possibility of publication bias was examined by constructing funnel plots. Additionally, subgroup and sensitivity analyses were performed.

RESULTS

Thirty-four studies were included with a total of 9613 patients. Tailored therapy proved superior to empiric treatment [OR 2.07 (95% CI 1.53-2.79)]. However, tailored therapy achieved eradication rates >90% in only 15 (44%) studies and >95% in only 6 (17.6%).

CONCLUSIONS

Although tailored therapy performed better than empiric treatment, the lack of optimization of therapies failed to reliably achieve high cure rates (>90%). These results emphasize that H. pylori infection, like other infectious diseases, should utilize the principles of antimicrobial stewardship in relation to treatment guidance.

Personalized Approach in Eradication of Helicobacter pylori Infection

The increase in antibiotic resistance to Helicobacter pylori (H. pylori) is associated with a decrease in the effectiveness of eradication therapy. Although some success has been achieved by adjusting therapeutic regimens according to local data on resistance to certain antibiotics, a new approach is needed to ensure a better therapeutic response. Tailored therapy, based on sensitivity tests to antibiotics, is increasingly proving to be a superior therapeutic option, even as a first-line therapy. Moreover, the recently published Maastricht VI guidelines emphasize utilizing a susceptibility-guided strategy in respect to antibiotic stewardship as the first choice for eradication therapy. In addition, polymerase chain reaction (PCR) technology is becoming a standard tool in the diagnosis of H. pylori infections through non-invasive testing, which further optimizes the eradication process. We provide a review regarding the current position of the individualized approach in eradication therapy and its future prospects. Based on novel understandings, the personalized approach is an effective strategy to increase the successful eradication of H. pylori infections.

Tailored therapy for Helicobacter pylori eradication: A systematic review and meta-analysis

Background: Due to an increase in drug resistance, the eradication rate of H. pylori with empirical therapy has declined. Tailored therapy has been proposed as an alternative to standard empirical treatments. The necessity of personalized eradication therapy remains unclear. The aim of this study was to determine whether tailored therapy is superior to empirical therapy for H. pylori infection.

Methods: We searched for eligible randomized controlled trials in the PubMed, Embase (Ovid), Wanfang, and Cochrane Central Register of Controlled Trials databases up to 10 December 2021. A random effects model comparing pooled relative risks (RRs) with 95% confidence intervals (CIs) was applied in the meta-analysis.

Results: Twenty-one studies were included in the meta-analysis. In the first-line treatment, tailored therapy was more effective than empirical therapy (RR, 1.14 [95% CI, 1.08–1.21], I² = 72.2%). In the second-line therapy setting, the results did not reveal significant differences between the two treatments (RR, 1.05 [95% CI, 0.84–1.30], I² = 80.6%). A similar result was observed in mixed second- and third-line treatments (RR, 1.03 [95% CI, 0.96–1.11], I² = 0.0%). Regarding adverse events, no significant differences were found between the two treatments (RR, 0.90 [95% CI, 0.80–1.01], I² = 35.7%). Most of the results were highly heterogeneous.

Conclusion: A tailored approach might provide a better eradication rate than empirical methods in first-line treatment. There might be no obvious advantage in second-line or mixed second- and third-line treatments third-line treatment. Due to the high heterogeneity, the results should be interpreted with caution. Further clinical studies are needed and justified.

A randomized controlled trial to compare Helicobacter pylori eradication rates between the empirical concomitant therapy and tailored therapy based on 23S rRNA point mutations

BACKGROUND

Increasing clarithromycin resistance has led to changes in several guidelines for treatment of Helicobacter pylori infections. We compared the H. pylori eradication rates of the empirical concomitant therapy (CoT) and a tailored therapy (TaT) using dual-priming oligonucleotide-based polymerase chain reaction to detect mutations in the 23S rRNA gene that are related to clarithromycin resistance.

METHODS

Between June 2020 and May 2021, 290 patients were enrolled and randomly assigned to 2 groups. In the CoT group, the patients received rabeprazole 20 mg, amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg twice daily for 14 days. In the TaT group, point mutation-negative patients received rabeprazole 20 mg, amoxicillin 1 g, and clarithromycin 500 mg twice daily for 14 days and point mutation-positive patients received rabeprazole 20 mg twice daily, metronidazole 500 mg thrice daily, and bismuth 120 mg and tetracycline 500 mg 4 times daily for 14 days.

RESULTS

A total of 290 and 261 patients were included in the intention-to-treat (ITT) and per-protocol (PP) analyses, respectively. A2142G and/or A2143G point mutations were identified in 28.6% of the patients. No significant difference in eradication rates were observed between the 2 groups as per ITT (CoT, 82.8% and TaT, 85.5%, P = .520) and PP (CoT, 88.6% and TaT, 94.6%, P = .084) analyses. In point mutation-positive patients, the eradication rates in the CoT group were lower than those in the TaT group as per ITT (69.8% and 87.5%, respectively, P = .050) and PP (76.9% and 97.1%, respectively, P = .011) analyses.

CONCLUSION

CoT and TaT showed similar overall eradication rates for H. pylori. However, CoT eradication rate was suboptimal, especially in point mutation-positive patients.

Susceptibility testing alone will not reliably achieve high Helicobacter pylori cure rates: A systematic review and meta-analysis

BACKGROUND AND AIM

Not all the susceptibility-guided therapies for Helicobacter pylori (H. pylori) infection achieve excellent eradication rates. The aim of this study was to perform a systematic review and meta-analysis to identify the optimal regimen for H. pylori treatment based on antibiotic susceptibility.

METHODS

A systematic search was performed in multiple databases. Studies reporting eradication rates of H. pylori with susceptibility-guided therapies were selected. Meta-analysis was conducted to calculate the pooled eradication rate among the treatment regimens.

RESULTS

Forty-eight eligible studies with 101 susceptibility-guided treatment arms were included. The overall eradication rate in patients harboring susceptible strains was 95.0% (95% CI, 94.1-95.9%), but only 63.4% of treatment arms (64/101) achieved good eradication rates (≥ 90%). Pooled eradication rates in patients with susceptible strains were: 93.4% (95% CI, 92.0-94.8%) for clarithromycin, 99.0% (95% CI, 98.1-100%) for nitroimidazoles and 95.4% (95% CI, 93.6-97.2%) for fluoroquinolones. Among the arms using a triple therapy, 66.7% (28/42) using clarithromycin, 84.2% (16/19) using nitroimidazoles and 70.8% (17/24) using fluoroquinolones achieved good (≥ 90%) eradication rates. Of 13 arms using sequential therapy, ≥ 90% eradication was achieved in 14.3% (1/7) using clarithromycin, 25.0% (1/4) using nitroimidazoles and both arms (2/2) using fluoroquinolones.

CONCLUSIONS

Susceptibility testing alone seemed insufficient to reliably attain high H. pylori cure rates. The eradication rate in patients with nitroimidazoles susceptible strains was higher than those of fluoroquinolones and clarithromycin.

Empirical vs. Susceptibility-Guided Treatment of Helicobacter pylori Infection: A Systematic Review and Meta-Analysis

Background

Treating Helicobacter pylori infection according to antibiotic resistance has been frequently recommended. However, information on its real effectiveness is scarce.

Aim

The aim of this study is to perform a meta-analysis comparing empirical vs. susceptibility-guided treatment of H. pylori.

Methods

Selection of studies: Studies comparing empirical versus susceptibility-guided treatment were selected. Search strategy: electronic and manual up to August 2021. Data synthesis: by intention-to-treat (random-effects model).

Results

Overall, 54 studies were included (6,705 patients in the susceptibility-guided group and 7,895 in the empirical group). H. pylori eradication rate was 86 vs. 76%, respectively (RR: 1.12; 95% CI: 1.08-1.17; I 2: 83%). Similar results were found when only RCTs were evaluated (24 studies; RR: 1.16; 95% CI: 1.11-1.22; I 2: 71%) and when susceptibility testing was assessed by culture (RR: 1.12; 95% CI: 1.06-1.18) or PCR (RR: 1.14; 95% CI: 1.05-1.23). For first-line treatments (naïve patients; 30 studies), better efficacy results were obtained with the susceptibility-guided strategy (RR: 1.15; 95% CI: 1.11-1.20; I 2: 79%). However, for empirical first-line quadruple regimens, in particular (both with and without bismuth, excluding the suboptimal triple therapies), not based on CYP2C19 gene polymorphism, no differences in efficacy were found compared with the susceptibility-guided group (RR: 1.04; 95% CI: 0.99-1.09); this lack of difference was confirmed in RCTs (RR: 1.05; 95% CI: 0.99-1.12). For rescue therapies (13 studies, most 2nd-line), similar results were demonstrated for both strategies, including all studies (RR: 1.09; 95% CI: 0.97-1.22; I 2: 82%) and when only RCTs were considered (RR: 1.15; 95% CI: 0.97-1.36).

Conclusion

The benefit of susceptibility-guided treatment over empirical treatment of H. pylori infection could not be demonstrated, either in first-line (if the most updated quadruple regimens are prescribed) or in rescue therapies.

Study on the value of antibiotic-resistant gene detection in Helicobacter pylori in China

The aim of the present study was to explore the value of detecting antibiotic-resistant genes in Helicobacter pylori (H. pylori) and the association between genotype and antibiotic resistance. Two gastric mucosa samples from each H. pylori-positive patient were collected. Each patient's H. pylori sample was cultured in vitro, and the agar plate dilution method was conducted. In addition, all patient samples were analyzed for the detection of antibiotic resistance-related mutant genes and VacA gene genotypes. The association between VacA genotypes and antibiotic resistance was also determined and the value of mutant gene detection in predicting H. pylori resistance to antibiotics was evaluated. In total, 133 H. pylori-positive patients were enrolled. A total of 22 strains of H. pylori failed to grow in in vitro culture and 25 strains were negative in a H. pylori gene test. Among 108 strains detected by PCR, a total of 39 VacA s1m1 strains, 69 VacA s1m2 strains and no VacA s2 strain were identified. There was no significant association between VacA genotypes and antibiotic resistance. The mutation rates of G616A in the rdxA gene, T87A, G91A, A91G and G91T in the gyrA gene and A2143G and A2142G in the 23S rRNA gene were 32.1, 32.3, 22.6, 12.9, 6.5, 81.8 and 0.0%, respectively. Among these mutant sites, the mutation coincidence rates were as follows, according to the agar plate dilution method: rdxA G616A (81.8%), gyrA G91T (66.7%), gyrA G91A (54.5%), 23 S rRNA A2143G (49.1%), gyrA T87A (45.5%), gyrA A91G (33.3%), penicillin-binding protein 1 (PBP1) C556G (0.0%), PBP1 A562T (0.0%), PBP1 A562G (0.0%) and 16 S rRNA 926-927 (AT-GT) (0.0%). VacA m subtypes were not associated with H. pylori antibiotic resistance. In conclusion, the present findings suggested that the detection of related mutant genes had a clinical application value in predicting the antibiotic resistance of H. pylori, particularly resistance to clarithromycin and levofloxacin.

Bismuth-Based Quadruple Therapy versus Metronidazole-Intensified Triple Therapy as a First-Line Treatment for Clarithromycin-Resistant Helicobacter pylori Infection: A Multicenter Randomized Controlled Trial

Background/Aims

Clarithromycin resistance is a main factor for treatment failure in the context of Helicobacterpylori infection. However, the treatment regimen for clarithromycin-resistant H. pylori infection has not yet been determined. We aimed to compare the efficacy and cost-effectiveness of 14-day bismuth-based quadruple therapy versus 14-day metronidazole-intensified triple therapy for clarithromycin-resistant H. pylori infection with genotypic resistance.

Methods

This was a multicenter, randomized, controlled trial. A total of 782 patients with H. pylori infection examined using sequencing-based clarithromycin resistance point mutation tests were recruited between December 2018 and October 2020 in four institutions in Korea. Patients with significant point mutations (A2142G, A2142C, A2143G, A2143C, and A2144G) were randomly assigned to receive either 14-day bismuth-based quadruple therapy (n=102) or 14-day metronidazole-intensified triple therapy (n=99).

Results

The overall genotypic clarithromycin resistance rate was 25.7% according to the sequencing method. The eradication rate of 14-day bismuth-based quadruple therapy was not significantly different in the intention-to-treat analysis (80.4% vs 69.7%, p=0.079), but was significantly higher than that of 14-day metronidazole-intensified triple therapy in the per-protocol analysis (95.1% vs 76.4%, p=0.001). There were no significant differences in the incidence of side effects. In addition, the 14-day bismuth-based quadruple therapy was more cost-effective than the 14-day metronidazole-intensified triple therapy.

Conclusions

Fourteen-day bismuth-based quadruple therapy showed comparable efficacy with 14-day metronidazole-intensified triple therapy, and it was more cost-effective in the context of clarithromycin-resistant H. pylori infection.

Detection of clarithromycin resistance and 23SrRNA point mutations in clinical isolates of Helicobacter pylori isolates: Phenotypic and molecular methods

BACKGROUND AND OBJECTIVES

Peptic ulcer disease, chronic gastritis, and stomach cancer are all caused by H. pylori. The most notable drug for the treatment is the antibiotic clarithromycin, which is currently the drug of choice. H. pylori clarithromycin resistance has been associated with point mutations in 23srRNA, the most prominent of which are A2143 and A2144G. In H. pylori bacteria, methylase synthesis, macrolide-inactivating enzyme activity, and active efflux have all been found to be resistance mechanisms. The goal of the study is to determine how resistant H. pylori is to clarithromycin and what the minimum inhibitory concentration is for various antimicrobials. Furthermore, gastro-endoscopy will be performed on Iraqi patients to detect the presence of A2143G and A2144G point mutations in Helicobacter pylori infections, as diagnosed from the pyloric region and other anatomical regions.

METHODS

One hundred fifteen samples were collected from patients strongly suspected of H. pylori infection presented for upper gastrointestinal endoscopy at Ramadi Teaching Hospitals and Private Clinics for the period from January 2020 until February 2021. Specimens were cultured on brain heart infusion agar containing various antibiotics and were incubated at 37 °C under microaerophilic conditions. For identification of H. pylori, isolates of the biochemical tests and RT-PCR assay were applied. The Epsilometer test was used in the antibiotic susceptibility testing as dependent on the CLSI standard. The Restriction Fragment Length Polymorphism technique was used to determine point mutations.

RESULTS

In total, 55 (47.8%) Helicobacter pylori isolates were cultured from the 115 biopsy specimens, among which 16 (29.1%), 38 (69.1%), 20 (36.4%), and 40 (72.7%) revealed some degree of resistance to levofloxacin, clarithromycin, ciprofloxacin, and metronidazole, respectively. The frequency of A2144G and A2143 point mutations were 23 (60.5%) and 19 (50%), respectively.

CONCLUSIONS

According to our results, Helicobacter pylori showed high resistance to clarithromycin. Our results demonstrate the requirement for antibiotic susceptibility testing and molecular methods in selecting drug regimens.

Comparison of tailored Helicobacter pylori eradication versus modified bismuth quadruple therapy in Korea: a randomized controlled trial

OBJECTIVES

We aimed to compare the success rate, adverse drug events, and cost-effectiveness of tailored Helicobacter pylori eradication and modified bismuth-containing quadruple therapy.

METHODS

The diagnosis of H. pylori infection was randomly based on either rapid urease test (RUT) or dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) in 1:1 ratio. According to the presence of point mutations that cause clarithromycin resistance, patients in the tailored therapy (TT) group received standard triple therapy or classic bismuth quadruple therapy. Patients with positive RUT results received 40 mg pantoprazole, 1000 mg amoxicillin, 750 mg metronidazole, and 600 mg bismuth subcitrate twice daily for 14 days (PAM-B therapy).

RESULTS

Between the TT (n = 141) and PAM-B groups (n = 141), H. pylori eradication rate did not differ significantly according to intention-to-treat (TT: 80.9% vs. PAM-B: 85.8%, P = 0.262), modified intention-to-treat (TT: 89.1% vs. PAM-B: 91.0%, P = 0.606), and per-protocol (TT: 89.0% vs. PAM-B: 93.5%, P = 0.198) analyses. The average cost for successful eradication was higher in the TT group than in the PAM-B group ($340.7 vs. $263.9 per patient).

CONCLUSION

PAM-B therapy exhibits similar efficacy and improved cost-effectiveness compared to TT based on the results of DPO-PCR tests.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifier is NCT05002595.

Timing of prior exposure to antibiotics and failure of Helicobacter pylori eradication: a population-based study

BACKGROUND

The success rate of conventional Helicobacter pylori eradication therapy is declining, due to rising antibiotic resistance.

OBJECTIVES

To determine the temporal effects of prior antibiotic exposure on eradication outcome.

PATIENTS AND METHODS

This is a retrospective cohort study including all H. pylori-infected patients who received their first course of clarithromycin-containing triple therapy in 2003-18. Prior antibiotic exposures before H. pylori eradication therapy (up to 180 days, 1 year or 3 years) were retrieved. A logistic regression model was used to evaluate the association between different timings of previous antibiotic exposure, recent (within 30/60 days) or distant period, and the need for retreatment for H. pylori.

RESULTS

A total of 120 787 H. pylori-infected patients were included. Prior exposure to any antibiotics within 180 days was associated with a higher risk of retreatment (OR 1.18, 95% CI 1.13-1.24) and the risk progressively increased with longer duration of antibiotic use. The results were consistent for prior exposure up to 1 year (OR 1.26, 95% CI 1.20-1.31) or 3 years (OR 1.30, 95% CI 1.25-1.35). However, when compared with those without prior antibiotic exposure, recent exposure (within 30 days) did not increase the risk of retreatment, which was consistent for analysis with prior antibiotic exposure up to 3 years. Notably, recent use of cephalosporins within 30/60 days and nitroimidazole within 30 days had significantly lower risks of retreatment.

CONCLUSIONS

Any prior antibiotic exposure increased the risk of treatment failure of clarithromycin-containing triple therapy. Recent exposures to some classes of antibiotics may paradoxically increase treatment success.

Susceptibility-guided versus empirical treatment for Helicobacter pylori infection: A systematic review and meta-analysis

BACKGROUND AND AIM

Empirical therapy for Helicobacter pylori infection is limited by increasing antibiotic resistance and suboptimal eradication rates. Studies of the relative effectiveness of susceptibility-guided therapy have produced conflicting results. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine whether susceptibility-guided therapy is superior to empirical therapy for H. pylori infection.

METHODS

We searched articles listed in PubMed, MEDLINE, EMBASE, and Web of Science through May 25, 2020, RCTs comparing susceptibility-guided versus empirical therapy for H. pylori infection. Outcomes, including effectiveness and safety, were analyzed in a meta-analysis.

RESULTS

Our final analysis included 16 studies, comprising 2374 patients who received susceptibility-guided therapy and 2451 patients who received empirical treatment. In previously untreated subjects, susceptibility-guided therapy was slightly more effective than empirical therapy (intent to treat risk ratio [RR], 1.14; 95% confidence interval [CI], 1.07-1.21; P < 0.0001, I²  = 75%). Susceptibility-guided therapy was superior to first-line clarithromycin-based triple therapy only when clarithromycin resistance exceeded 20% (RR, 1.18; 95% CI, 1.07-1.30; P = 0.001, I²  = 81%). Susceptibility-guided therapy was not more effective than empirical quadruple therapy (RR, 1.02; 95% CI, 0.92-1.13; P = 0.759, I²  = 80%). Three RCTs were performed exclusively among previously treated subjects, and were highly heterogeneous.

CONCLUSIONS

Our findings suggest that susceptibility-guided treatment may be slightly superior to empirical first line triple therapy. Susceptibility- guided treatment does not appear to be superior to empirical first-line quadruple therapy or empirical rescue therapy.

Tailored eradication strategy vs concomitant therapy for Helicobacter pylori eradication treatment in Korean patients

BACKGROUND

Antibiotic resistance to Helicobacter pylori (H. pylori) infection, which ultimately results in eradication failure, has been an emerging issue in the clinical field. Recently, to overcome this problem, an antibiotic sensitivity-based tailored therapy (TT) for H. pylori infection has received attention.

AIM

To investigate the efficacy and safety profiles of TT for H. pylori infection treatment compared to a non-bismuth quadruple therapy, concomitant therapy (CT) regimen.

METHODS

We included patients (> 18 years) with an H. pylori infection and without a history of Helicobacter eradication who visited the Gil Medical Center between March 2016 and October 2020. After being randomly assigned to either the TT or CT treatment group in 1 to 1 manner, patient compliance, eradication success rate (ESR), and patient-reported side effects profiles were assessed and compared between the two groups. H. pylori infection was diagnosed using a rapid urease test, Giemsa stain, or dual priming oligonucleotide polymerase chain reaction (DPO-PCR). Tailored eradication strategy based through the presence of a 23S ribosomal RNA point mutation. For the TT group, a DPO-PCR test, which detected A2142G and/or A2143G point mutations, and a clarithromycin resistance test were performed. Patients in the clarithromycin-resistant group were treated with a bismuth-containing quadruple combination therapy, while those with sensitive results were treated with the standard triple regimen.

RESULTS

Of the 217 patients with a treatment naive H. pylori infection, 110 patients [mean age: 58.66 ± 13.03, men, n = 55 (50%)] were treated with TT, and 107 patients [mean age: 56.67 ± 10.88, men, n = 52 (48.60%)] were treated with CT. The compliance (TT vs CT, 100% vs 98.13%, P = 0.30), and follow-up loss rates (8.18% vs 9.35%, P = 0.95) were not significantly different between the groups. The ESR after treatment was also not statistically different between the groups (TT vs CT, 82.73% vs 82.24%, P = 0.95). However, the treatment-related and patient-reported side effects were significantly lower in the TT group than in the CT group (22.77% vs 50.52%, P < 0.001).

CONCLUSION

The DPO-based TT regimen shows promising results in efficacy and safety profiles as a first-line Helicobacter eradication regimen in Korea, especially when physicians are confronted with increased antibiotic resistance rates.

Efficacy of Seven-day High-dose Esomeprazole-based Triple Therapy versus Seven-day Standard Dose Non-esomeprazole-based Triple Therapy as the First-line Treatment of Patients with Helicobacter pylori Infection

Background/Aims

The rates of Helicobacter pylori (H. pylori) eradication have declined with the use of proton pump inhibitor- amoxicillin-clarithromycin as the first-line triple therapy. On the other hand, several studies have suggested that high gastric pH levels could affect the H. pylori eradication rate by enhancing the efficacy of antimicrobials. This study compared the efficacy of seven-day high-dose esomeprazole-based triple therapy (7-HEAC) for first-line H. pylori eradication with the seven-day standard dose non-esomeprazole-based triple therapy (7-NEAC) to identify the risk factors related to eradication failure.

Methods

This study included 223 patients who were diagnosed with a H. pylori infection and received 7-HEAC or 7-NEAC between June 2016 and January 2017. The H. pylori eradication rates, as well as demographic and clinical factors, were investigated retrospectively. H. pylori eradication was confirmed by a ¹³C-urea breath test or rapid urease test at least 4 weeks after the completion of therapy.

Results

The eradication rates were 67.7% (105/155; 95% CI 59.5-74.8%) in the 7-NEAC group and 80.9% (55/68; 95% CI 69.9-89.8%) in the 7-HEAC group (p=0.045). The adverse event rates were 5.8% (9/155) in the 7-NEAC group and 7.4% (5/68) in the 7-HEAC group (p=0.661). Multivariate analysis revealed being female (OR 2.08; 95% CI 1.15-3.76) to be associated with the failure of H. pylori eradication therapy.

Conclusions

The eradication rate of the 7-HEAC group was higher than that of the 7-NEAC group. Nevertheless, more effective first-line therapies may be necessary for H. pylori eradication in the near future.

The effect of previous eradication failure on antibiotic resistance of Helicobacter pylori: A retrospective study over 8 years in Beijing

BACKGROUND

Antibiotic resistance is the main cause of Helicobacter pylori (H. pylori) treatment failure. This study aimed to explore the characteristics of antibiotic resistance of H. pylori isolates in Beijing in the last 8 years and to estimate the impact of previous eradication failure on resistance patterns.

MATERIALS AND METHODS

This retrospective study included data from a single center in Beijing from 2013 to 2020. Antibiotic susceptibility of 365 clinical H. pylori isolates was tested for amoxicillin, clarithromycin, metronidazole, levofloxacin, moxifloxacin, and tetracycline. The characteristics of the included patients and their previous eradication history were collected. Primary and secondary resistance rates of H. pylori to the six antibiotics and the impact of previous eradication failure on antibiotic resistance patterns were analyzed.

RESULTS

The overall primary resistance rates of amoxicillin, clarithromycin, metronidazole, levofloxacin, moxifloxacin, and tetracycline were 0.7%, 55.2%, 68.0%, 49.7%, 64.5%, and 0%, with no significant increase during the observed period; while the secondary resistance rates were 3.2%, 96.7%, 90.7%, 93.1%, 80.0%, and 0%, respectively. The secondary resistance rate of clarithromycin (p < .001), metronidazole (p = .001), and levofloxacin (p < .001) significantly increased to 100% as the number of previous eradication therapies increased and exhibited a linear association. For strains naive to eradication, only 6.8% were susceptible to all the antibiotics, while 32.4% were single resistant, and 60.8% dual or multiple resistant. Clarithromycin+metronidazole+fluoroquinolone multiple resistance was the predominant pattern (0 course: 21.6%, 1 course: 37.5%, 2 courses: 56.1%, ≥3 courses: 71.1%; p < .001) for patients with treatment failure. The prevalence of dual or multiple-resistance patterns increased significantly as the number of previous therapies increased.

CONCLUSIONS

The prevalence of primary and secondary resistance rates of clarithromycin, metronidazole, moxifloxacin, and levofloxacin were high in Beijing. Multiple-resistance patterns were common after treatment failure. Resistance rates of amoxicillin and tetracycline remained low and stable.

Seven-day triple therapy is sufficient to eradicate infection caused by Helicobacter pylori without 23S rRNA point mutation

ABSTRACT

Tailored therapy based on dual priming oligonucleotide-based polymerase chain reaction (DPO-PCR) can be considered an alternative to overcome the low eradication rate in high clarithromycin-resistance areas. The triple therapy (TT) duration of the tailored approach in most studies was 7 days for patients without point mutation. However, recent western guidelines have recommended a treatment duration of 14 days. The aim of this study was to compare the success rate of 7 and 14 days of TT for eradicating Helicobacter pylori without point mutation, as determined by DPO-PCR.Between Feb 2016 and Feb 2019, medical records of patients who underwent DPO-PCR were reviewed. Patients without point mutation as determined by DPO-PCR were enrolled in this study. The eradication success rate and adverse events were evaluated.A total of 366 patients without A2142G and A2143G point mutation were enrolled. The success rates of 7-day and 14-day TT were 88.4% (168/190) and 85.9% (151/176) by intention to treat analysis (P = .453) and 90.8% (168/185) and 90.4% (151/167) by per-protocol analysis (P = .900), respectively. The adverse event rates showed no significant difference between the 2 groups.In patients without point mutation based on DPO-PCR results, 7-day TT is as effective as 14-day TT. Therefore, 7 days may be considered as a cost-effective treatment duration in Korea.

AGA Clinical Practice Update on the Management of Refractory Helicobacter pylori Infection: Expert Review

The purpose of this CPU Expert Review is to provide clinicians with guidance on the management of Helicobacter pylori after an initial attempt at eradication therapy fails, including best practice advice on specific regimen selection, and consideration of patient and systems factors that contribute to treatment efficacy. This Expert Review is not a formal systematic review, but is based upon a review of the literature to provide practical advice. No formal rating of the strength or quality of the evidence was carried out. Accordingly, a combination of available evidence and consensus-based expert opinion were used to develop these best practice advice statements.

Treatment of Refractory Helicobacter pylori Infection-Tailored or Empirical Therapy

The treatment of refractory Helicobacter pylori remains challenging in clinical practice. Factors that should be considered in the treatment of refractory H. pylori infection include treatment length, dosage of antibiotics and proton pump inhibitors (PPIs), number of drugs, and the selection of appropriate antibiotics. Extending the treatment length of triple therapy and non-bismuth quadruple therapy to 14 days may increase the eradication rate compared with a shorter period (7 or 10 days). The use of a higher dose of PPIs or vonoprazan may also increase the efficacy of triple therapy. Four-drug therapy, including bismuth or non-bismuth quadruple therapies, usually achieve higher eradication rates than triple therapy. The addition of bismuth or metronidazole to levofloxacin-amoxicillin-PPI therapy may also increase the eradication rate. Therefore, four-drug therapies containing a higher dose of PPIs for 14 days are recommended in the third-line treatment setting for refractory H. pylori infection. The selection of appropriate antibiotics may be guided by susceptibility testing or empirically by medication history. Tailored therapy guided by susceptibility testing or genotypic resistance is recommended whenever possible. However, properly designed empirical therapy based on prior medication history (i.e., avoid the reuse of clarithromycin or levofloxacin empirically) is an acceptable alternative to tailored therapy after considering accessibility, cost, and the preference of the patient.

Recent progress in Helicobacter pylori treatment

The main challenge in the field of Helicobacter pylori (H. pylori) infection is antibiotic resistance, which influences the efficacy of eradication regimens. Bismuth-containing quadruple therapy has been confirmed as an effective regimen for eradicating H. pylori, especially in strains with antibiotic resistance. High-dose proton-pump inhibitor-amoxicillin dual therapy could decrease the use of unnecessary antibiotics, which is a promising alternative approach. Adjuvant therapy (specific probiotic or vitamin) also showed good results, although more evidence is needed. Novel anti-H. pylori drugs are needed, and the establishment of the H. pylori database is an effective way to acknowledge the real-time information of H. pylori management. This review provides the recent progress of H. pylori treatment, and further studies are needed to address the role of different regimens in improving H. pylori eradication rate, especially in strains with antibiotics resistance.

Empirical or susceptibility-guided treatment for Helicobacter pylori infection? A comprehensive review

Although susceptibility-guided therapy is frequently recommended for Helicobacter pylori infection, the evidence available to date supporting this strategy is limited. The aim of the present article is to review the advantages and limitations of the susceptibility-guided and the empirical strategies to treat this infection. We performed a bibliographic search to identify studies investigating H. pylori susceptibility-guided therapy. Culture is not the only way to assess antibiotic resistance, as different polymerase chain reaction-based approaches have been developed as alternative methods. For detecting H. pylori antimicrobial resistance, a molecular approach based on a stool sample might enable more convenient, time-saving methods. Unfortunately, the antimicrobial susceptibility cannot be obtained in all cases. Furthermore, antibiotic susceptibility testing in clinical practice yields useful information only for a few antibiotics: clarithromycin, metronidazole, and quinolones. In addition, susceptibility towards clarithromycin and metronidazole in vitro does not necessarily lead to eradication in vivo. In the case of H. pylori therapy failure, we should not re-administer any of the antibiotics against which H. pylori has probably become resistant. Our updated meta-analysis showed that susceptibility-guided treatment is not better than empirical treatment of H. pylori infection in first-line therapy if the most updated quadruple regimens are empirically prescribed, and similar efficacy results were also demonstrated with the two strategies for second-line therapy. Cumulative H. pylori eradication rate with several successive rescue therapies empirically prescribed reaches almost 100%. Finally, the studies that have evaluated the cost-effectiveness of the susceptibility-guided treatment have achieved contradictory results. In summary, we can conclude that the evidence is too limited to support the generalized use of susceptibility-guided therapy for H. pylori treatment in routine clinical practice, either as first-line or as rescue treatment. Nevertheless, it would be recommended that susceptibility tests are performed routinely, even before prescribing first-line treatment, in specialized centers with an interest in H. pylori management.

Validation of loop-mediated isothermal amplification to detect Helicobacter pylori and 23S rRNA mutations: A prospective, observational clinical cohort study

Background

Identifying point mutations in 23S rRNA closely associated with clarithromycin resistance can increase the eradication rate of Helicobacter pylori (H pylori). In this study, we verified the sensitivity, specificity, and reliability of a newly developed loop‐mediated isothermal amplification (LAMP) assay kit to detect H pylori and 2143G and 2182C mutations in 23S rRNA.

Methods

LAMP assay to detect H pylori and a mutant strain with 2143G and 2182C was conducted with the Isopollo^®H pylori & ClaR kit. A prospective, open‐label, observational study was conducted to validate the reliability of the LAMP assay in both a development cohort and a bedside direct LAMP cohort.

Results

The LAMP assay had good sensitivity, as it could detect as few as 10–100 copies of H pylori and mutants with 2143G and 2182C in 23S rRNA, and good specificity, as it did not react with other bacterial species. In the development cohort with 622 participants, the LAMP assay showed good agreement with RUT for detecting H pylori (kappa value 0.923, P < .001) and had exactly the same results as sequencing analysis for 2143G and 2182C point mutations. The direct LAMP cohort including 93 patients had 97.7% (42/43) of concordance in detecting 2143G and 2182C point mutations compared to the PCR‐based sequencing analysis.

Conclusion

The Isopollo^®H pylori & ClaR LAMP assay was a valid method for detecting H pylori and for 2143G and 2182C point mutations in 23S rRNA in a clinical setting.

Treatment of Helicobacter pylori infection and its long-term impacts on gut microbiota

The rising prevalence of antibiotic resistance and the long-term safety following eradication therapy are important issues in the management of Helicobacter pylori infection. The prevalence of clarithromycin, levofloxacin, and metronidazole resistance of H. pylori has increased to 21%, 27%, and 45%, respectively, in the Asia-Pacific region. Personalized treatment guided by susceptibility testing may provide a reliably excellent eradication rate in the first-line treatment but is costly and not widely available. Population-specific empirical therapy according to the local prevalence of antibiotic resistance may be an alternative strategy. Levofloxacin-based therapy and bismuth quadruple therapy are the recommended second-line rescue therapy. Susceptibility testing or genotypic resistance-guided therapy is the preferred treatment for refractory H. pylori infection, but empirical therapy may be an acceptable alternative. Eradication of H. pylori leads to short-term perturbation of gut microbiota. The diversity of gut microbiota can be restored months after eradication therapy, but the speed of recovery varies with regimens. The short-term increases of antibiotic resistance of Escherichia coli and Klebsiella pneumoniae may be restored to basal states months after H. pylori eradication. Future studies that apply in-depth sequencing, such as shotgun metagenomics sequencing, are needed to clarify whether the compositions of gut microbiota at the species level are fully restored.

Optimized diagnosis of Helicobacter pylori and tailored eradication therapy for preventing gastric cancer: a proposal for SHAKE strategy

INTRODUCTION

To decrease gastric cancer-related mortality, the Korean National Cancer Screening Program provides biennial screening gastroscopy to all individuals aged >40 years. However, a test-and-treat strategy of Helicobacter pylori for preventing gastric cancer has not been established.

AREAS COVERED

In this review, we present up-to-date results of endoscopic findings of H. pylori gastritis, optimal sites for H. pylori detection, gastric cancer risk assessment using serum pepsinogen, tailored eradication based on the antimicrobial resistance against H. pylori, and post-eradication surveillance.

EXPERT OPINION

Here we propose approaches to H. pylori diagnosis and treatment for preventing gastric cancer, termed 'Screening for H. pylori in Korea and Eradication (SHAKE)' strategy. This strategy consists of the following: (1) optimized H. pylori diagnosis, (2) individualized management based on the H. pylori infection status, and (3) tailored eradication therapy. H. pylori gastritis can be diagnosed by endoscopic observation of the gastric mucosal pattern at the greater curvature of the corpus. Measurement of the serum pepsinogen I/II ratio is useful for assessing the risk of gastric cancer. As a first-line treatment, tailored eradication based on the results of molecular testing is effective in a country with a high rate of clarithromycin-resistant H. pylori.

Molecular Assessment of Resistance to Clarithromycin in Helicobacter pylori Strains Isolated from Patients with Dyspepsia by Fluorescent In Situ Hybridization in the Center of Iran

Background and Aims

Helicobacter pylori is a common infectious bacterium mostly found in gastroduodenal diseases. The increased prevalence of clarithromycin-resistant H. pylori strains is a major challenge in the successful treatment of infections caused by this organism. The present study is aimed at detecting the clarithromycin resistance pattern of H. pylori strains isolated from gastric biopsies and evaluating point mutations of the 23S rRNA gene. Patients and methods. In the present descriptive cross-sectional study, 165 patients with gastrointestinal disorders, who were referred to the Endoscopy Center of Dr. Shariati Hospital of Isfahan, Iran, were enrolled from April to July 2018. H. pylori infection was diagnosed by culture, and susceptibility of the isolates to clarithromycin was assessed by the E-test. Minimum inhibitory concentration (MIC) values were obtained based on EUCAST recommendations. Also, fluorescence in situ hybridization (FISH) was used to determine point mutations associated with clarithromycin resistance.

Results

By using culturing, H. pylori was isolated from 50.3% (83/165) gastric biopsy specimens. The overall frequency of resistance to clarithromycin was 25.3% (21/83) by the E-test. In the resistance genotypic analysis, 19 isolates had mutations. The prevalence of A2143G and A2144G mutations was 68.4% (13/19) and 31.5% (6/19), respectively. A2143C mutation was not tracked in any isolate. Two isolates with MIC > 0.5 μg/mL had no mutations that could be related to other mechanisms of resistance.

Conclusion

As presented in the study, the high prevalence of clarithromycin-resistant H. pylori due to point mutations of the 23S rRNA gene indicates the necessity of revising the standard treatment regimen based on antibiotic susceptibility pattern of each region.