Antimicrobial Susceptibility Testing for Helicobacter pylori Is Now Widely Available: When, How, Why

Helicobacter pylori Antimicrobial Resistance and the Role of Next-Generation Sequencing

Helicobacter pylori infection affects over half of the world's population and is a global health concern because it contributes to chronic and fatal gastrointestinal disorders, including peptic ulcer disease and gastric cancer. The escalating prevalence of antibiotic-resistant strains of H pylori necessitates a change in management. The conventional strategy of empiric-based treatments is becoming increasingly ineffective in both adult and pediatric populations; rates of eradication to common first-line regimens remain suboptimal and continue to decline. Culture-based susceptibility testing for H pylori has been underutilized and challenging to incorporate into practice. Next-generation sequencing (NGS), which can identify the genetic biomarkers that predict antimicrobial resistance and susceptibility patterns, offers a promising alternative. NGS may enable clinicians to tailor individual treatment regimens and contribute to epidemiologic surveillance across populations. As NGS technology advances and becomes more accessible, its integration into routine clinical practice holds the potential to transform H pylori management strategies and improve patient outcomes. This article reviews the literature describing antimicrobial resistance patterns in adult and pediatric practice in the United States and provides practical guidance on the current role of NGS in the management of H pylori.

Functional determination of site-mutations in rdxA involved in metronidazole resistance of Helicobacter pylori

Background

Metronidazole (MTZ) is among the first-line drugs against the human gastric pathogen Helicobacter pylori (H. pylori). MTZ is used as a prodrug that is activated by an oxygen-insensitive enzyme NADPH nitroreductase (RdxA). Loss-of-function mutations in rdxA make H. pylori MTZ resistant; however, experimental proof is lacking.

Methods

We collected 139 gastric biopsy samples from patients suspected of H. pylori infection in Shanghai, and amplified Hp-specific rdxA gene from 134 samples. All these rdxA genes were sequenced and phylogenetically compared. The effect of mutations on RdxA function was measured by expressing them in Escherichia coli DH5α by using the MTZ sensitivity test.

Results

In total, 134 gastric biopsy samples were identified as H. pylori positive. Of the 134 samples, 74 and 6 had point mutations at the various sites or promoter region of rdxA, generating truncated and extended fused proteins, respectively. The remaining 54 were full-length with single nucleotide variation (SNV) compared with the wild-type RdxA from H. pylori, with 49 clustering with hpEastAsia, 3 with hpEurope, and 2 with hpNEAfrica. All 134 rdxA were expressed in E. coli DH5α; 22 and 112 resultant strains showed MTZ-sensitive and MTZ-resistant phenotypes, respectively. Comparative analysis of single nucleotide polymorphisms (SNPs) in the functional and inactivated RdxA revealed 14 novel mutations in RdxA, 5 of which conferred MTZ resistance: S18F, D59S, L62I, S79N, and A187V.

Conclusion

The occurrence of MTZ resistance induced by site-mutation of RdxA in patients with H. pylori infection was 83.6% (112/134) in the Shanghai region. The major form of loss-of-function mutation was truncation of RdxA translation at a rate of 58/112 (51.8%). Molecular detection reliably determined the resistance of H. pylori to MTZ. Thus, the functional mutants involved in MTZ resistance facilitate clinical diagnosis and medication based on sequence analysis.

Point Mutations in Furazolidone and Rifampicin Resistance Genes in Helicobacter pylori Strains from Colombia

The eradication of Helicobacter pylori is a valid strategy for preventing gastric cancer; however, the therapeutic failure of first-line treatments in Colombia is associated with high resistance to metronidazole and amoxicillin. This study explored alternative antibiotics and analyzed point mutations in resistance genes to furazolidone and rifampicin in order to include them in rescue therapy regimens. A total of 239 complete genomes of Helicobacter pylori Colombian strains were compared to that of the ATCC 26695 strain to identify mutations in the rpoB and porD genes for rifampicin and furazolidinone resistance, respectively. While rifampicin resistance mutations were not found, only 0.84% of the isolates showed the porD gene, suggesting that Helicobacter pylori is sensitive to these antibiotics. A phylogenomic analysis of Helicobacter pylori revealed an independent lineage in Colombia (hspColombia). The absence of point mutations in the rpoB gene, together with the scarce mutations identified in the porD gene of Helicobacter pylori, suggest that the hspColombia isolates are sensitive to rifampicin and furazolidone, which could be key to including these antibiotics in the rescue therapies against Helicobacter pylori.

Peptic ulcer disease

Annual prevalence estimates of peptic ulcer disease range between 0·12% and 1·5%. Peptic ulcer disease is usually attributable to Helicobacter pylori infection, intake of some medications (such as aspirin and non-steroidal anti-inflammatory medications), or being critically ill (stress-related), or it can be idiopathic. The clinical presentation is usually uncomplicated, with peptic ulcer disease management based on eradicating H pylori if present, the use of acid-suppressing medications-most often proton pump inhibitors (PPIs)-or addressing complications, such as with early endoscopy and high-dose PPIs for peptic ulcer bleeding. Special considerations apply to patients on antiplatelet and antithrombotic agents. H pylori treatment has evolved, with the choice of regimen dictated by local antibiotic resistance patterns. Indications for primary and secondary prophylaxis vary across societies; most suggest PPIs for patients at highest risk of developing a peptic ulcer, its complications, or its recurrence. Additional research areas include the use of potassium-competitive acid blockers and H pylori vaccination; the optimal approach for patients at risk of stress ulcer bleeding requires more robust determinations of optimal patient selection and treatment selection, if any. Appropriate continuation of PPI use outweighs most possible side-effects if given for approved indications, while de-prescribing should be trialled when a definitive indication is no longer present.

Self-Correcting Method for Highly Effective Office-Based Helicobacter pylori Therapy Using Cumulative Test of Cure Data

BACKGROUND AND AIM

Helicobacter pylori infections have become resistant to many previously highly effective antimicrobial regimens resulting in clarithromycin, metronidazole, or fluoroquinolone-containing therapies becoming unsuccessful. Pretreatment susceptibility testing is only widely available in the United States but is still rarely done. Here, we propose a framework to monitor H. pylori eradication in small clinical settings by routinely assessing the effectiveness of therapy.

METHODS

Because of the small sample size in individual practice's, we assume an acceptable cure rate of ≥80% (preferred cure rate ≥85%) in adherent patients, with a dichotomous outcome (cured vs. failed) and consecutive patient enrollment. To obtain results (feedback) in a timely manner, for individual practices, cure rates can be estimated after 10 patients. Large practices which acquire patients more rapidly can delay analysis until a total of 104 H. pylori-infected patients, assuming a baseline cure rate of at least 85% with the preferred regimen.

RESULTS

We show how data from individual practices can be utilized to improve the effectiveness of H. pylori treatment decisions. The method consists of recording and accumulating the confirmation of cure data for successive small groups of patients. These data are then analyzed as binary outcomes (pass-fail) and serve as the basis for studying and improving the effectiveness of H. pylori treatment decisions.

CONCLUSION

A simple actuarial method can serve outpatient clinics to ensure a reliable test-to-cure method and avoid futile Hp regimens.

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.

Current and Future Perspectives on the Management of Helicobacter pylori: A Narrative Review

The prevalence of Helicobacter pylori (H. pylori), a pathogen, has decreased globally in the last decade. To date, the management of H. pylori has focused on a reactive approach, whereby those diagnosed are treated with antimicrobials and acid suppression in combination. This review article provides an overview of the shift in the management of H. pylori from a reactive approach towards a proactive 'screen and treat' approach; the article reflects the current pharmacological landscape for H. pylori treatment by exploring similarities such as the first-line prescription of quadruple therapy in most countries and provides a summary table of the best practice guidance from Europe, Asia, and North America. It explores significant ongoing challenges in management, such as rising antimicrobial resistance rates, and explores a potential 'work smart' approach to antimicrobial susceptibility testing. We explore the role of registry databases in providing data on treatment efficacy and safety and how they can support a strategic approach to H. pylori treatment. We question if such a database's availability, update, and regular audit should serve as a key quality indicator in a population screening programme. Despite a call for vaccination against H. pylori and decades of research, not many have made it to a phase-three clinical trial. We explore the challenges that have complicated the development of such a vaccine, such as the genetic diversity of H. pylori, immunotolerance, and limitations of mouse models in research; we reflect on how these challenges are contributing to a low likelihood of having a vaccine in the short-medium term. Lastly, it explores the heterogeneity in research on probiotics and their role as an adjunct in the management of H. pylori.

Helicobacter pylori Diagnosis and Treatment in Africa: The First Lagos Consensus Statement of the African Helicobacter and Microbiota Study Group

BACKGROUND

Helicobacter pylori (H. pylori) infection is the most prevalent type of bacterial infection. Current guidelines from different regions of the world neglect specific African conditions and requirements. The African Helicobacter and Microbiota Study Group (AHMSG), founded in 2022, aimed to create an Africa-specific consensus report reflecting Africa-specific issues.

SUMMARY

Eighteen experts from nine African countries and two European delegates supported by nine African collaborators from eight other countries prepared statements on the most important African issues in four working groups: (1) epidemiology, (2) diagnosis, (3) indications and prevention, and (4) treatment. Limited resources, restricted access to medical systems, and underdeveloped diagnostic facilities differ from those of other regions. The results of the individual working groups were presented for the final consensus voting, which included all board members.

KEY MESSAGES

There is a need for further studies on H. pylori prevalence in Africa, with diagnosis hinged on specific African situation. Treatment of H. pylori in the African setting should be based on accessibility and reimbursement, while indication and prevention should be defined in specific African countries.

H. Pylori Treatment in the COVID-19 Era. What Have We Learned So Far?

PURPOSE OF REVIEW

CoronaVirus Disease of 2019 (COVID-19) has negatively influenced the management of multiple conditions in regards to the gastroenterology patient. An equivalent change in the management of Helicobacter pylori (H. pylori)-related diseases was reported, as practically no eradication treatment was offered during most of the pandemic. Given the scarcity of published data, we performed a literature review trying to elucidate the effect of COVID-19 on H. pylori treatment.

RECENT FINDINGS

COVID-19 has produced more questions than answers as to the outcome of COVID-19 in H. Pylori infected patients, post-COVID-19 patients treated for H. pylori, acid suppression and COVID-19 incidence and outcomes, and H. pylori eradication treatment in patients having recovered from COVID-19. We strongly believe that this scientific uncertainty produced by the COVID-19 pandemic has set up the stage for an incremental change in H. pylori treatment as COVID-19 has offered us the chance to speed up how we will, in the near future, approach patients with a possible Η. pylori infection.

Best Practices for Helicobacter pylori Management

For decades, antimicrobial therapy for Helicobacter pylori infection has been given empirically, and the results of therapy (success or failure) have either not been confirmed or when confirmed have not been used to modify prescribing behavior. These practices coupled with increasing antibiotic resistance have resulted in low cure rates overall. Susceptibility testing for H pylori has increasingly become available, especially in the United States. Availability of susceptibility-based therapy has encouraged adoption of the principles of antimicrobial stewardship for H pylori infection (eg, limiting antibiotic choice to antibiotics for which the infection is susceptible given at optimal doses, formulations, frequency of administration, and duration). Antimicrobial regimens can now be classified as empiric therapies, susceptibility-based therapies, potentially effective therapies requiring optimization, and therapies containing unneeded antibiotics that should not be used. This article describes current best practices and recommendations for integrating culture-based and molecular-based susceptibility testing into H pylori therapy.

Testing for Helicobacter pylori in an era of antimicrobial resistance

Antimicrobial resistance in Helicobacter pylori has reached alarming levels and is compromising traditional empiric treatment of H. pylori. Antimicrobial susceptibility testing is routinely performed for infectious diseases when there is a risk of resistance and is now recommended to guide therapy for H. pylori. This mini-review overviews the current diagnostics for H. pylori with a focus on tests that enable susceptibility-guided treatment, including molecular tests performed directly on stool and endoscopically collected specimens.

Evolving Concepts in Helicobacter pylori Management

Helicobacter pylori is the most common chronic bacterial infection worldwide and the most significant risk factor for gastric cancer, which remains a leading cause of cancer-related death globally. H pylori and gastric cancer continue to disproportionately impact racial and ethnic minority and immigrant groups in the United States. The approach to H pylori case-finding thus far has relied on opportunistic testing based on symptoms or high-risk indicators, such as racial or ethnic background and family history. However, this approach misses a substantial proportion of individuals infected with H pylori who remain at risk for gastric cancer because most infections remain clinically silent. Moreover, individuals with chronic H pylori infection are at risk for gastric preneoplastic lesions, which are also asymptomatic and only reliably diagnosed using endoscopy and biopsy. Thus, to make a significant impact in gastric cancer prevention, a systematic approach is needed to better identify individuals at highest risk of both H pylori infection and its complications, including gastric preneoplasia and cancer. The approach to H pylori eradication must also be optimized given sharply decreasing rates of successful eradication with commonly used therapies and increasing antimicrobial resistance. With growing acceptance that H pylori should be managed as an infectious disease and the increasing availability of susceptibility testing, we now have the momentum to abandon empirical therapies demonstrated to have inadequate eradication rates. Molecular-based susceptibility profiling facilitates selection of a personalized eradication regimen without necessitating an invasive procedure. An improved approach to H pylori eradication coupled with population-level programs for screening and treatment could be an effective and efficient strategy to prevent gastric cancer, especially in minority and potentially marginalized populations that bear the heaviest burden of H pylori infection and its complications.

Success of susceptibility-guided eradication of Helicobacter pylori in a region with high secondary clarithromycin and levofloxacin resistance rates

BACKGROUND

Resistance to clarithromycin (CLA) and levofloxacin (LFX) of Helicobacter pylori (H. pylori) is increasing in severity, and successful eradication is essential. Presently, the eradication success rate has greatly declined, leaving a large number of patients with previous treatment histories.

AIM

To investigate secondary resistance rates, explore risk factors for antibiotic resistance, and assess the efficacy of susceptibility-guided therapy.

METHODS

We recruited 154 subjects positive for Urea Breath Test who attended The First Affiliated Hospital of China Medical University between July 2022 and April 2023. Participants underwent a string test after an overnight fast. The gastric juice was obtained and transferred to vials containing storage solution. Subsequently, DNA extraction and the specific DNA amplification were performed using quantitative polymerase chain reaction (qPCR). Demographic information was also analyzed as part of the study. Based on these results, the participants were administered susceptibility-guided treatment. Efficacy was compared with that of the empiric treatment group.

RESULTS

A total of 132 individuals tested positive for the H. pylori ureA gene by qPCR technique. CLA resistance rate reached a high level of 82.6% (n = 109), LFX resistance rate was 69.7% (n = 92) and dual resistance was 62.1% (n = 82). Gastric symptoms [odds ratio (OR) = 2.782; 95% confidence interval (95%CI): 1.076-7.194; P = 0.035] and rural residence (OR = 5.152; 95%CI: 1.407-18.861; P = 0.013) were independent risk factors for secondary resistance to CLA and LFX, respectively. A total of 102 and 100 individuals received susceptibility-guided therapies and empiric treatment, respectively. The antibiotic susceptibility-guided treatment and empiric treatment groups achieved successful eradication rates of 75.5% (77/102) and 59.0% (59/411) by the intention-to-treat (ITT) analysis and 90.6% (77/85) and 70.2% (59/84) by the per-protocol (PP) analysis, respectively. The eradication rates of these two treatment strategies were significantly different in both ITT (P = 0.001) and PP (P = 0.012) analyses.

CONCLUSION

H. pylori presented high secondary resistance rates to CLA and LFX. For patients with previous treatment failures, treatments should be guided by antibiotic susceptibility tests or regional antibiotic resistance profile.

Management of Helicobacter pylori treatment failures: A large population-based study (HP treatment failures trial)

BACKGROUND

Helicobacter pylori treatment failure remains a challenging problem. This study aimed to identify predictive factors for successful eradication in patients following treatment failures.

METHODS

This was a retrospective cohort study. This study included 1,050 dyspeptic patients diagnosed with H. pylori infection at tertiary care center in Thailand between March 2014 and October 2021. Patients' demographic data, endoscopic findings, H. pylori culture, antimicrobial susceptibility testing (AST), treatment regimens and outcomes were analysed.

RESULTS

Of 1,050 patients with H. pylori infections, 302 (28.7%) experienced treatment failure (mean age 58.4 years; 44.7% males). AST was performed in 192. Resistance was observed for metronidazole (43.2%), levofloxacin (33.9%), clarithromycin (24%), and amoxicillin (2.1%). There was no tetracycline resistance. Multidrug-resistance (MDR) was significantly more common following treatment failure (45.5% vs. 15.7%, p<0.001). Baseline characteristics were similar between treatment successes and failures. Eradication rates after first-line and second-line regimens were 71.2% and 54.5%, respectively. Medication nonadherence [OR 36.6 (95%CI 8.65-155.03, p<0.001)] and MDR [OR 4.49 (95%CI 2.29-8.81, p<0.001)] were associated with treatment failure. Over time, resistance increased for metronidazole, levofloxacin, and clarithromycin, while eradication rates with triple therapy declined. Tailored antibiotic therapy [OR 4.92 (95%CI 1.61-14.99, p = 0.005)] and a regimen including 4-times-daily dosing of amoxicillin (2 grams/day) [OR 3.05 (95%CI 1.10-8.41, p = 0.032)] were significantly associated with treatment success after first-line failure. Eradication rates when using tailored therapy and 4-times-daily dosing of amoxicillin (2 grams/day) were 91.1% and 89.4%, respectively. Performing AST before first-line therapy resulted in the highest cure rates. AST performed after multiple treatment failures was also associated with higher eradication rates compared with the group without AST (94.4% vs. 50%,p = 0.008).

CONCLUSIONS

AST either before or after treatment failure correlated with a higher proportion of successful eradication. Nonadherence and the MDR infections predicted treatment failure. Tailored therapy and 4-times-daily dosing of amoxicillin after treatment failure were likely to be successful.

Eradicating Helicobacter pylori via 13C-urea breath screening to prevent gastric cancer in indigenous communities: a population-based study and development of a family index-case method

OBJECTIVE

Screening and eradication of Helicobacter pylori help reduce disparities in the incidence of gastric cancer. We aimed to evaluate its acceptability and feasibility in the indigenous communities and develop a family index-case method to roll out this programme.

DESIGN

We enrolled residents aged 20-60 years from Taiwanese indigenous communities to receive a course of test, treat, retest and re-treat initial treatment failures with the 13C-urea breath tests and four-drug antibiotic treatments. We also invited the family members of a participant (constituting an index case) to join the programme and evaluated whether the infection rate would be higher in the positive index cases.

RESULTS

Between 24 September 2018 and 31 December 2021, 15 057 participants (8852 indigenous and 6205 non-indigenous) were enrolled, with a participation rate of 80.0% (15 057 of 18 821 invitees). The positivity rate was 44.1% (95% CI 43.3% to 44.9%). In the proof-of-concept study with 72 indigenous families (258 participants), family members of a positive index case had 1.98 times (95% CI 1.03 to 3.80) higher prevalence of H. pylori than those of a negative index case. The results were replicated in the mass screening setting (1.95 times, 95% CI 1.61 to 2.36) when 1115 indigenous and 555 non-indigenous families were included (4157 participants). Of the 6643 testing positive, 5493 (82.6%) received treatment. According to intention-to-treat and per-protocol analyses, the eradication rates were 91.7% (89.1% to 94.3%) and 92.1% (89.2% to 95.0%), respectively, after one to two courses of treatment. The rate of adverse effects leading to treatment discontinuation was low at 1.2% (0.9% to 1.5%).

CONCLUSION

A high participation rate, a high eradication rate of H. pylori and an efficient rollout method indicate that a primary prevention strategy is acceptable and feasible in indigenous communities.

TRIAL REGISTRATION NUMBER

NCT03900910.

Helicobacter pylori Antimicrobial Resistance Using Next-Generation Sequencing in Stool Samples in a Pediatric Population

Helicobacter pylori ( H pylori ) eradication rates have declined globally, stressing the importance of antimicrobial susceptibility testing to inform treatment. Molecular tests such as next-generation sequencing (NGS) provide susceptibility data for the antibiotics used in the treatment of H pylori in a noninvasive, effective, and rapid manner. We obtained stool susceptibility testing using a novel NGS-based analysis and compared results with the current "gold standard" of gastric biopsy culture via agar dilution in 20 pediatric patients with evidence of H pylori in gastric biopsies. Stool NGS-based antimicrobial susceptibility analysis was highly concordant with agar dilution for no resistance (100% agreement), as well as clarithromycin, levofloxacin, and amoxicillin resistance (100%, 67%, and 100% agreement, respectively) but not concordant for metronidazole in our cohort of patients. Future studies involving a larger number of patients and geographical regions are needed to further validate this analysis.

Controversies regarding management of Helicobacter pylori infections

PURPOSE OF REVIEW

The recognition that Helicobacter pylori should be considered and treated as an infectious disease has yet to fundamentally change diagnostic and treatment practices and has resulted in many controversies.

RECENT FINDINGS

We discuss the following controversies: whether the current 'per-patient' approach to H. pylori testing based on symptoms should be expanded to include achieving population-level H. pylori eradication, whether H. pylori should be approached as an infectious gastrointestinal disease similar to that of other infectious diseases of similar severity and outcome, whether treatment of H. pylori should be primarily empiric or based on antibiotic susceptibility and locally proven successful therapies as are other infectious diseases, whether it is necessary to obtain confirmation of treatment success in every patient treated for H. pylori , and whether potassium-competitive acid blockers should replace proton pump inhibitors in H. pylori therapy.

SUMMARY

Available guidelines and meta-analyses do not yet address H. pylori as an infectious disease. The diagnosis and management and treatment success of H. pylori infections trails behind that of other important infectious diseases. We provide new insights and propose changes in the traditional understanding required to modernize the management of H. pylori infections.

The association between periodontal diseases and helicobacter pylori: an updated meta-analysis of observational studies

INTRODUCTION

Various studies have examined the association between periodontitis and helicobacter pylori and reported conflicting results. The aimed of this systematic review and meta-analysis estimating the association between these two variables.

METHODS

Electronic databases including PubMed (Medline), Scopus, Web of Sciences and Medline (Elsevier) were searched using the relevant keywords. All observational studies comparing the association between periodontitis and helicobacter pylori were considered. The Newcastle - Ottawa Quality Assessment Scale (NOS) checklist was used for assessing quality of included studies. All statistical analyses were completed using STATA (Version 16).

RESULTS

Twenty-three studies with 8,638 patients (15 case-control with 2,366 patients and 8 cross-sectional with 6,272 patients) were included in this meta-analysis. After combining the selected studies, the odds of presence the Helicobacter pylori infection in patients with the periodontal disease was 2.47 (OR: 2.47; 95% CI: 2.01, 3.03; I²: 50.87%; P: 0.001). Also, the odds after combining case-control studies was 2.77 (OR: 2.77; % 95 CI: 2.11, 3.66; I²: 37.16%; P: 0.049) and after combining cross-sectional analytical ones, it was equal to 2.07 (OR: 2.07; 95% CI: 1.62, 2.65; I²: 43.25%; P: 0.050).

CONCLUSION

Based on the results of this meta-analysis, the association between Helicobacter pylori infection and the periodontal disease is evident.

Advances in the pharmacological and regulatory management of multidrug resistant Helicobacter pylori

INTRODUCTION

Antibiotic resistance of Helicobacter pylori (H. pylori) hampers the success of eradication and in recent years multidrug resistance (MDR) shows an increase worldwide.

AREAS COVERED

This review covers current aspects of pharmacological and regulatory management of MDR-resistant H. pylori infection.

EXPERT OPINION

MDR H. pylori is increasing worldwide and its prevalence varies both between continents and countries. High consumption and misuse of antibiotics, H. pylori treatment failures and bacterial factors such as mutations, efflux pumps and biofilms are among the factors associated with MDR. Important steps for confronting the rise of MDR H. pylori strains should follow the principles of antibiotic stewardship, i.e. eradication regimens should be optimized with regard to all aspects of therapy, including drugs, doses, formulation, frequency of administration, administration in relation to meals and duration of therapy that reliably achieve at least 90% (preferably >95%) cure rates in adherent patients with susceptible infections.

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.

Colloidal bismuth pectin-containing quadruple therapy as the first-line treatment of Helicobacter pylori infection: A multicenter, randomized, double-blind, non-inferiority clinical trial

BACKGROUND

Bismuth-containing quadruple therapy is an effective regimen for Helicobacter pylori (H. pylori) treatment. No head-to-head comparison trials have been conducted to evaluate the efficacy of colloidal bismuth pectin (CBP) in quadruple therapy for eradicating H. pylori. We aimed to compare the efficacy and safety of CBP quadruple therapy and bismuth potassium citrate (BPC) quadruple therapy for 14 days in the first-line treatment of H. pylori.

METHODS

In this multicenter, randomized, double-blind, non-inferiority clinical trial, H. pylori-infected subjects without eradication history were randomized to receive amoxicillin 1 g twice daily, tetracycline 500 mg three time daily, esomeprazole 20 mg twice daily in combination with CBP 200 mg three time daily or BPC 240 mg twice daily for 14 days. ¹³ C-urea breath tests were used to access the eradication rate at least 4 weeks after treatment.

RESULTS

Between April 2021 and July 2022, 406 patients were assessed for eligibility and 339 subjects were randomized. The cure rates (primary outcome) of CBP and BPC quadruple therapy were 90.5% and 92.3% (p = 0.56) by intention-to-treat analysis, respectively, and 96.1% and 96.2% (p = 1.00) by per-protocol analysis, respectively. CBP quadruple therapy was non-inferior to BPC quadruple therapy in the intention-to-treat and per-protocol analysis (p < 0.025). The frequency of adverse events and compliance were not different among the two groups (p > 0.05).

CONCLUSIONS

Both CBP and BPC quadruple therapy for 14 days provide high efficacy, good compliance, and safety in the first-line treatment of H. pylori in China.

Helicobacter pylori Infection: Antibiotic Resistance and Solutions for Effective Management in Africa

Helicobacter pylori (H. pylori) infection is ubiquitous worldwide, with prevalence rates of greater than 70% in Africa. Symptomatic patients present with foregut gastrointestinal symptoms which can be readily diagnosed with standardized non-invasive or invasive tests. The biggest challenge, however, is in the management of this condition with rising antimicrobial resistance rates to most of the antibiotics recommended for therapy. This is a problem worldwide, but more specifically in Africa, where the socio-economic and political climate is such that eradication of this organism seems impossible. Furthermore, the recommended antimicrobial susceptibility testing for drug resistance is not widely available in Africa due to the lack of infrastructural as well as human resources. With the widespread unregulated use of antibiotics in some parts of Africa, the figures of antimicrobial resistance are likely to soar. In the face of these significant challenges, this 'perspectives' article aims to address the issue of antimicrobial resistance in Africa, by providing achievable and targeted goals to curb the spread of infection and rising antimicrobial resistance.

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

Controlling Gastric Cancer in a World of Heterogeneous Risk

Gastric cancer (GC) is a leading cause of global mortality but also a cancer whose footprint is highly unequal. This review aims to define global disease epidemiology, critically appraise strategies of prevention and disease attenuation, and assess how these strategies could be applied to improve outcomes from GC in a world of variable risk and disease burden. Strategies of primary prevention focus on improving the detection and eradication of the main environmental risk factor, Helicobacter pylori. In certain countries of high incidence, endoscopic or radiographic screening of the asymptomatic general population has been adopted as a means of secondary prevention. By contrast, identification and targeted surveillance of individuals with precancerous lesions (such as intestinal metaplasia) is being increasingly embraced in nations of low incidence. This review also highlights existing knowledge gaps in GC prevention as well as the role of emerging technologies for early detection and risk stratification.

Implications of the paradigm shift in management of Helicobacter pylori infections

The recent availability of susceptibility testing for Helicobacter pylori infections in the United Sates has resulted in paradigm shifts in the diagnosis, therapy, and follow-up of H. pylori infections. Here, we reviewed the English literature concerning changes in H. pylori diagnosis and therapy with an emphasis on the last 3 years. We focus on the new methods that offer rapid and convenient susceptibility testing using either invasive (endoscopic) or noninvasive (stool) methods of obtaining test material. We also discuss the implications of this availability on therapy and follow-up after therapy. The approach to therapy was categorized into four groups: (1) therapies that can be used empirically, (2) therapies that should be restricted to those that are susceptibility-based, (3) potentially effective therapies that have yet to be optimized for local use, and (4), therapies that contain unneeded antibiotics that should not be prescribed. The most convenient and efficient method of susceptibility testing is by using reflexive stool testing in which if the sample is positive, it is automatically also used for determination of susceptibility. Reflexive testing can also be done via reflexive ordering (e.g., for all positive urea breath tests). The post therapy test-of-cure has emerged as a critical component of therapy as it not only provides feedback regarding treatment success but when combined with susceptibility testing also provide evidence regarding the cause of failure (e.g., poor adherence versus emergence of resistance during therapy. Susceptibility testing has made even the most current H. pylori guidelines for diagnosis and therapy generally obsolete. Clarithromycin, metronidazole, and levofloxacin triple therapies should only be administered as susceptibility-based therapy. Regimens containing unneeded antibiotics should not be given. We provide recommendations regarding the details and indications for all current therapies.

Why the Vonoprazan Helicobacter pylori Therapies in the US-European Trial Produced Unacceptable Cure Rates

INTRODUCTION

Helicobacter pylori infects a large percentage of the world's population and is etiologically related to gastric cancer. The U.S. Food and Drug Administration recently approved two 14-day vonoprazan-containing regimens (vonoprazan-amoxicillin with or without clarithromycin) for H. pylori infections in the United States/Europe.

METHODS

We critically reviewed the trial methods to discover why the results were unacceptable low [i.e., no regimen achieved clinically acceptable (≥ 90%) or even conditionally acceptable cure rates (≥ 85%)]. Cure rates with antibiotic susceptible strains were 84.7 for vonoprazan triple therapy, 78.5 for vonoprazan-amoxicillin, and 78.7 for lansoprazole triple therapy, respectively. As was previously shown in Japan, the benefit from adding clarithromycin to vonoprazan-amoxicillin was minimal and the majority of the clarithromycin administered was unnecessary.

RESULTS

The possible reasons for failure to achieve high cure rates discussed include (a) reduced intragastric antibiotic concentrations, (b) an increase in heteroresistance, and (c) failure to achieve an intragastric pH conducive for amoxicillin to eradicate the infection. In addition, there was no pilot study or other attempt to optimize any regimen.

CONCLUSION

The most likely reason for failure was failure to achieve high intragastric concentrations of antibiotics or to achieve an intragastric pH conducive for amoxicillin to be active. Importantly, vonoprazan triple therapy resulted in > 10 tons of unneeded clarithromycin/million courses of vonoprazan triple therapy. Antibiotic misuse combined with low cure rates suggest that vonoprazan-clarithromycin triple therapies should not be prescribed for H. pylori infection. Dual vonoprazan-amoxicillin therapy has proven effective elsewhere and after optimization may eventually prove useful in the U.S./Europe.

Individualized diagnosis and eradication therapy for Helicobacter pylori infection based on gene detection of clarithromycin resistance in stool specimens: A systematic review and meta-analysis

BACKGROUND

Empiric therapy for Helicobacter pylori infection results in significantly increased antibiotic resistance and decreased eradication efficacy. The genotypic testing of clarithromycin resistance from stool specimens is a promising method for individualized diagnosis and treatment. This study aimed to determine the status of research and application on this method through a systematic review and meta-analysis.

METHODS

PubMed, Embase, MEDLINE, and WAN FANG database were searched for relevant literature. The quality of included diagnostic articles was evaluated using the quality Assessment of Diagnostic Accuracy Studies-2 tool. A bivariate random-effect model was conducted to calculate the diagnostic accuracy of genotypic testing of clarithromycin resistance.

RESULTS

A total of 16 diagnostic-related were included and analyzed after exclusions. The pooled sensitivity and specificity of diagnostic meta-analysis were 0.93 (95% confidence interval [CI]: 0.90-0.96) and 0.98 (95% CI: 0.93-1.00), respectively. The area under the curve (AUC) of the summary receiver operating characteristic was 0.97 (95% CI: 0.95-0.98). The genotypic testing in stool samples had heterogeneous sensitivity (Q = 37.82, p < .01, I²  = 37.82) and specificity (Q = 60.34, p < .01, I²  = 93.72) in detecting clarithromycin resistance. Purification method, stool sample weight, real-time PCR, and antimicrobial susceptibility testing as reference accounted for the heterogeneity of pooled sensitivity, while patient age, purification method, stool sample weight, and real-time PCR for the heterogeneity of pooled specificity.

CONCLUSION

The genotypic testing of clarithromycin resistance from stool specimens is an accurate, convenient, noninvasive, and rapid detection technology, providing a definitive diagnosis of clarithromycin resistance and guiding the rational antibiotic selection.

Tailored Treatment Based on Helicobacter pylori Genetic Markers of Resistance Is Associated With Higher Eradication Success

INTRODUCTION

Increasing antimicrobial resistance with Helicobacter pylori infection has focused efforts to tailor eradication therapy based on identifying genetic markers of resistance to predict antimicrobial susceptibility.

METHODS

In this retrospective study, we report the effect of routine inclusion of antimicrobial susceptibility testing and recommendations for eradication therapy with gastric specimens with H. pylori .

RESULTS

The use of a recommended treatment regimen based on genetic markers of resistance was associated with an 84% rate of eradication success and 4.4 greater odds of eradication relative to unrecommended treatment.

DISCUSSION

This is the first study describing the use of H. pylori genetic resistance testing as standard of care.

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.

A Simplified Low-Dose 10-Day Quadruple Therapy with a Galenic Formulation of Bismuth Salicylate Is Highly Effective for Helicobacter pylori Eradication

BACKGROUND

Earlier studies have shown that a modified low-dose bismuth quadruple therapy given for 10 to 14 days is highly effective for the treatment of Helicobacter pylori infection in Sardinia. However, bismuth is not universally available.

AIM

We aimed to investigate the efficacy of a simplified low-dose 10-day quadruple therapy containing a galenic formulation of bismuth salicylate for H. pylori infection.

PATIENTS AND METHODS

Adult patients positive for H. pylori infection were assigned to a quadruple therapy containing a galenic formulation of bismuth salicylate (200 mg) plus tetracycline 500 mg, metronidazole 500 mg and rabeprazole 20 mg, given twice a day with the midday and evening meals for 10 days. A negative stool antigen test or 13C-Urea Breath Test defined successful eradication. Compliance and adverse events were recorded 30-40 days after the end of treatment.

RESULTS

In this open-label pilot study, 42 patients were enrolled (mean age 54.1 ± 12.0 years; 64% female). Among the study participants, 35 were naïve to H. pylori treatment. The treatment regimen was completed by 41 patients, with an overall success rate of 95.1%. More specifically, the eradication rate was 95.1% PP; 95% confidence interval (CI) = 86.6-100 and 92.9% by ITT; 95%CI = 85.1-100%, respectively. For naïve patients, the cure rate was 97.1%. Compliance was excellent. Side effects were absent or mild overall.

CONCLUSIONS

The modified low-dose 10-day quadruple therapy provided high eradication rates of H. pylori infection, despite the replacement of colloidal bismuth subcitrate with bismuth salicylate. In regions where bismuth is unavailable in the market, the galenic formulation should be a valid option.

Tailored triple plus bismuth therapy based on previous antibiotic medication history for first-line Helicobacter pylori eradication: A randomized trial

INTRODUCTION

There are no randomized controlled trials that demonstrate the role of tailored therapy based on past medication history in improving efficacy of H. pylori eradication compared to empiric therapies. The objective of this study was to determine whether tailored triple plus bismuth therapy (TBT) can achieve higher eradication rates based on previous antibiotic history than empiric TBTs.

METHODS

800 treatment-naïve patients were randomly assigned to four groups receiving clarithromycin-, levofloxacin- or metronidazole-containing empiric TBT and tailored TBT (clarithromycin and levofloxacin chosen based on previous macrolides and quinolones medication history). Correlation analyses were performed between past medication history and resistance or eradication rate.

RESULTS

The eradication rates of tailored TBT were significantly higher than clarithromycin-, levofloxacin- and metronidazole-containing empiric TBT in both intention-to-treat (89.5%, 80.8%, 81.5% and 81.5%) and per-protocol (95.1%, 86.7%, 86.5% and 87.8%) analyses (P<0.05). In patients with previous macrolides, quinolones or nitroimidazoles medication history, the resistance rates of corresponding clarithromycin, levofloxacin or metronidazole were significantly higher than patients without past medication history, and the eradication rates of corresponding clarithromycin- or levofloxacin-containing empiric TBT were significantly lower.

CONCLUSION

Tailored TBT based on previous antibiotic history can achieve higher eradication rates than empiric TBT for first-line H. pylori eradication.

Effectiveness of 7-day triple therapy with half-dose clarithromycin for the eradication of Helicobacter pylori without the A2143G and A2142G point mutations of the 23S rRNA gene in a high clarithromycin resistance area

Background

Tailored therapy has been widely used for patients with Helicobacter pylori (H. pylori) infection in South Korea. Herein, we evaluated the treatment outcomes of tailored clarithromycin-based triple therapy (TT) in patients infected with H. pylori.

Methods

We enrolled 460 patients without A2142G and A2143G point mutations by dual priming oligonucleotide-based polymerase chain reaction who had taken TT and undergone the urease breath test to evaluate eradication in clinical practice. Eradication rates according to the treatment duration and dose of clarithromycin were analyzed.

Results

Among 460 patients (164 women, median age 63.0 years), 250 patients underwent TT with full-dose clarithromycin (TT-full CLA), and 216 patients underwent TT with half-dose clarithromycin (TT-half CLA). The eradication rates were 88.0% (220/250) in patients with TT-full CLA and 85.2% (179/210) in patients with TT-half CLA. In 250 patients with TT-full CLA, the eradication rates were 86.8% (33/38) in patients with 7-day TT-full CLA and 88.2% (187/212) in patients with 10-day or 14-day TT-full CLA (P = 0.788). In 210 patients with TT-half CLA, the eradication rates were 84.2% (139/165) in those with a 7-day TT-half CLA and 88.9% (40/45) in those with a 10-day or 14-day TT-half CLA (P = 0.436).

Conclusion

For patients with H. pylori infection without A2142G and A2143G point mutations by DPO-PCR in clinical practice, treatment extension above 7-day TT with full CLA did not improve the eradication rates. Future studies on the treatment outcomes of TT-half CLA considering effectiveness and compliance are warranted.

How widespread and convenient H. pylori susceptibility testing will result in pharmacological opportunities

INTRODUCTION

Until recently, antimicrobial therapy for Helicobacter pylori infections was almost universally empirical and based on a combination of expert opinion and local effectiveness. However, the new requirement that all therapeutic regimens reliably achieve high cure rates, the introduction of potassium competitive acid blockers and the availability of susceptibility testing many pharmacological opportunities particularly since all current therapies will require optimization. The ability to rapidly and inexpensively obtain H. pylori susceptibility data using stool samples makes obtaining susceptibility data practical and allows using susceptibility-based therapy routinely for both treatment-naïve patient and treatment failures.

AREAS COVERED

We searched the literature from 1990 to current to identify studies reporting the effect of susceptibility testing on H. pylori treatment. This review examines how widespread and convenient H. pylori susceptibility testing will result in pharmacological opportunities. . Many pharmacological opportunities will emanate from a renewal of efforts to develop, propagate, confirm, and update best practices based on local and regional susceptibility/resistance patterns.

EXPERT OPINION

The ability to evaluate treatment decisions and outcomes in susceptible infections and reliably achieve high cure rates should foster precise tailoring of pharmacologic therapy and should achieve the goals of high cure rates while preventing antimicrobial misuse and extending the useful life of current antibiotics.

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.

Clinical Implication of Drug Resistance for H. pylori Management

Rates of antimicrobial-resistance among H. pylori strains are increasing worldwide, resulting in declining eradication rates with current therapies, especially those containing clarithromycin or levofloxacin. To improve H. pylori management, a paradigm shift is needed, from the empiric approaches formerly employed, to regimen selection based upon knowledge of local and patient-level antimicrobial susceptibility data. We review the mechanisms of H. pylori antimicrobial resistance and the available worldwide pattern of resistance to key antimicrobials used in H. pylori therapy. The practicalities and challenges of measuring susceptibility in clinical practice is discussed, including not only conventional culture-based techniques but also novel sequencing-based methods performed on gastric tissue and stool samples. Though clinical trials of "tailored" (susceptibility-based) treatments have yet to show the clear superiority of tailored over empiric regimen selection, the ability to measure and modify treatment based upon antimicrobial susceptibility testing is likely to become more frequent in clinical practice and should lead to improved H. pylori management in the near future.

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

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

Helicobacter pylori Antibiotic Resistance in the United States Between 2011 and 2021: A Systematic Review and Meta-Analysis

INTRODUCTION

Antimicrobial resistance among Helicobacter pylori strains has been rising globally, leading to declining eradication rates. We performed a systematic review and meta-analysis of the resistance patterns of H. pylori strains in the United States between 2011 and 2021.

METHODS

Ovid MEDLINE, Embase, CINAHL, and Cochrane CENTRAL databases were searched for manuscripts and conference abstracts published between 2011 and 2021 reporting H. pylori antibiotic resistance. A mixed-effects model estimated pooled rates of resistance to clarithromycin, amoxicillin, metronidazole, tetracycline, rifabutin, levofloxacin, or a combination of these, with 95% confidence intervals (CIs).

RESULTS

A total of 19 studies including 2,660 samples, met inclusion criteria. The pooled rate of resistance to metronidazole was 42.1% (95% CI 27.3%-58.6%), levofloxacin 37.6% (95% CI 26.3%-50.4%), clarithromycin 31.5% (95% CI 23.6%-40.6%), amoxicillin 2.6% (95% CI 1.4%-5.0%), tetracycline 0.87% (95% CI 0.2%-3.8%), rifabutin 0.17% (95% CI 0.00%-10.9%), and dual clarithromycin and metronidazole 11.7% (95% CI 0.1%-94.0%). Considerable data heterogeneity was evident for pooled resistance prevalence rates (I 2 &gt; 50%), with the exception of rifabutin resistance.

DISCUSSION

Metronidazole, levofloxacin, and clarithromycin resistance rates each exceed 30%; thus, choosing an empiric antibiotic regimen without knowledge of the likely pattern of antibiotic resistance is not appropriate. Resistance to tetracycline, rifabutin, and amoxicillin remains low. Given the scarcity of available data with considerable heterogeneity among studies, continued surveillance, ideally with a more systematic approach to data collection, is an increasingly important goal in H. pylori management.

Helicobacter pylori Treatment Regimens: A US Perspective

Helicobacter pylori infects nearly one-third of the US population. H pylori is a significant cause of gastroduodenal disease, including peptic ulcers and cancers. However, rising antibiotic resistance has complicated management of H pylori. This article provides a practical review of management strategies, including first-line empiric therapies and how to treat patients when prior therapies fail. Bismuthbased quadruple therapy remains the standard initial empiric regimen, although a rifabutin-based triple regimen is another approach for empiric therapy in the United States. Clarithromycin and levofloxacin therapies should be avoided except when treating a strain of known susceptibility. When therapies fail, resistance should be tested with molecular or culture-based methods. Knowing local resistance patterns and/or using practice-based eradication rates is important for devising logic-based clinical choices. Ultimately, shared decision-making, patient counseling, and careful attention to drug type and dosage are essential for refractory cases.