High antibiotic resistance of Helicobacter pylori and its effect on tailored and empiric eradication of the organism in Lower Silesia, Poland

Meta-analysis of Helicobacter pylori eradication therapy using vonoprazan as an acid suppressor compared with bismuth quadruple therapy

BACKGROUND

Vonoprazan, a novel acid suppressant, has recently emerged as a regimen for eradicating Helicobacter pylori. However, uncertainties exist about the effectiveness and safety of VPZ-based regimens compared with those of bismuth-based quadruple therapy in eradicating H. pylori. The present meta-analysis was performed to compare the effectiveness and safety of vonoprazan-based regimens with those of bismuth quadruple therapy in eradicating H. pylori.

MATERIALS AND METHODS

All randomized controlled trials and non-randomized controlled trials comparing the vonoprazan-based therapy with the bismuth quadruple therapy were included in this meta-analysis. Information was also extracted by two evaluators, and if heterogeneity existed, a random-effects model was used to calculate the combined relative ratio and 95% confidence interval; otherwise, a fixed-effects model was used. And subgroup analyses were performed to explore the sources of heterogeneity.

RESULTS

A total of 10 studies, comprising 2587 patients were included in the meta-analysis. The results showed that the combined eradication rate of patients treated with the vonoprazan-based regimen was significantly higher than that of patients treated with bismuth quadruple therapy, in both intention-to-treat and per-protocol analyses, and the differences were statistically significant. Among the intention-to-treat analyses results: (90.28% vs. 83.64% [odds ratio (OR) = 1.85, 95% confidence interval (CI) (1.27, 2.70), p = 0.001]); in the per-protocol analyses: (94.80% vs. 89.88%, [OR = 2.25, 95% CI (1.37, 3.69), p = 0.001]). The occurrence of adverse events was significantly lower in patients treated with vonoprazan-based regimens than in those treated with bismuth quadruple therapy, (14.50% vs. 25.89%, [OR = 0.49, 95% CI (0.32, 0.75), p = 0.001]).

CONCLUSIONS

For eradicating H. pylori, vonoprazan-based regimens are remarkably advantageous over bismuth quadruple therapy. Furthermore, vonoprazan-based regimens exhibit a lower rate of adverse events than bismuth quadruple therapy.

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.

The prevalence of clarithromycin-resistant Helicobacter pylori isolates: a systematic review and meta-analysis

Background

Knowledge of global clarithromycin (CLA)-resistant rates of Helicobacter pylori (H. pylori) is crucial for decision of the most appropriate eradication therapies with good clinical outcomes. Therefore, this review and meta-analysis aimed to evaluate the global prevalence of the CLA resistance in H. pylori to provide some guidance for selecting the first-line antibiotics.

Method

A comprehensive search was performed for relevant literature until April 2021 in PubMed, Embase, and Web of Science databases. Freeman-Tukey double arcsine transformation was performed to estimate the weighted pooled prevalence of resistance.

Results

The meta-analysis included 248 articles. The prevalence of CLA-resistant H. pylori was 27.53% (95% CI [25.41-29.69]). The heterogeneity between reports was significant (I² = 97.80%, P < 0.01). The resistance rate increased from 24.28% in 2010-2017 to 32.14% in 2018-2021 (P < 0.01). Iran, with 38 articles, has the most report. Nevertheless, Switzerland, Portugal, and Israel had the highest resistance rates (67.16%, 48.11%, and 46.12%, respectively). The heterogeneity between the continents and the antimicrobial susceptibility methods also interpreted standard guidelines and breakpoints was insignificant (P > 0.05).

Conclusion

Overall CLA resistance rate was 27.53%, worldwide. The difference in CLA resistance rate among the included studies can be due to several reasons such as differences in antibiotic prescription rates in various geographic areas, use of different breakpoints or inaccurate criteria in performed studies, and the emergence of multidrug-resistant (MDR) strains.

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.

The pharmacotherapeutic management of duodenal and gastric ulcers

INTRODUCTION

Although the incidence and prevalence of duodenal and gastric ulcers have been declining, it remains challenging for health care systems. Based on the underlying cause, history, and characteristics of ulcers, management is generally provided by administering proton pump inhibitors (PPIs) or antibiotics.

AREAS COVERED

This article is based on global guidelines and English language literature from the past decade obtained through searches using PubMed, Clinicaltrials.gov, the US FDA, and the Cochrane library. Using a stepwise approach, dose and duration of treatment, drug interactions, warnings and contraindications, adverse effects, and administration points were specified. New drug candidates that may get American and European approvals were also introduced.

EXPERT OPINION

Despite the wide use of PPIs, their development lags behind the clinical need. There is an absolute requirement to develop third-generation PPIs with higher potency and improved pharmacokinetic and safety profiles. Regarding the antibiotic resistance crisis, including those used against H. pylori, conducting more clinical trials and investigating regional antibiotic resistance are warranted. Potassium competitive acid blockers, ilaprazole, and an H. pylori vaccine all show promise for the future.

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.

Primary Resistance Pattern of Helicobacter pylori to Antibiotics in Adult Population: A Systematic Review

Background

Helicobacter pylori is a spiral-shaped gram-negative bacteria associated with peptic ulcer, gastritis and gastric cancer. The global burden and occurrence of H. pylori infection remains prevalent and worldwide. Despite this, the trend of the bacterial resistance is not recently studied which can help in the adoption of global, regional and local prevention strategies.

Objective

The aim of the study was to systematically review the existing published literature that presents the estimate of H. pylori antibiotic resistance.

Methods

A protocol was primarily registered in PROSPERO International prospective register of systematic reviews and has given a registration number CRD42017068710. It was registered after checking whether there was similar study being conducted. A database search (PubMed/Medline and Google scholar) was used to collect relevant articles. A standardized form was prepared for the extraction of relevant data from studies which fulfilled the eligibility criteria. A National Institute for Health research (NIH)-based quality assessment tool was utilized to assess the quality of studies included in the study.

Results

Our searching process has retrieved a total of 288 publications which later resulted in 38 articles for full-text review. Among the 38 articles reviewed in full text, 14 studies were included which fulfilled the inclusion criteria. H.pylori-pooled overall prevalence rate of antibiotic resistance was found to be 4.55% (95% confidence interval (CI): 3.96–5.22%) to amoxicillin, 27.22% (95% CI: 25.89–28.58%) to clarithromycin, 39.66% (95% CI: 38.20–41.15%) to metronidazole, and 22.48% (95% CI: 21.24–23.76%) to levofloxacin.

Conclusion

The primary antibiotic resistance pattern of H. pylori is increasing worldwide. Thus, implementation of local drug susceptibility surveillance program, rational prescribing and use of antibiotics are necessary.

Application of 16S rRNA gene sequencing in Helicobacter pylori detection

Helicobacter pylori is one of the major stomach microbiome components, promoting development of inflammation and gastric cancer in humans. H. pylori has a unique ability to transform into a coccoidal form which is difficult to detect by many diagnostic methods, such as urease activity detection, and even histopathological examination. Here we present a comparison of three methods for H. pylori identification: histological assessment (with eosin, hematoxylin, and Giemsa staining), polymerase chain reaction (PCR) detection of urease (ureA specific primers), and detection by 16S rRNA gene sequencing. The study employed biopsies from the antral part of the stomach (N = 40). All samples were assessed histologically which revealed H. pylori in eight patients. Bacterial DNA isolated from the bioptates was used as a template for PCR reaction and 16S rRNA gene sequencing that revealed H. pylori in 13 and in 20 patients, respectively. Thus, 16S rRNA gene sequencing was the most sensitive method for detection of H. pylori in stomach biopsy samples.

Role of Vonoprazan in Helicobacter pylori Eradication Therapy in Japan

Complete eradication of Helicobacter pylori is important for preventing the development of gastric cancer. The outcome of H. pylori eradication therapy is mainly dependent on bacterial susceptibility to antimicrobial agents and potent neutralization of intragastric pH across 24 h, especially when using acid-sensitive antimicrobial agents such as clarithromycin (CLR), amoxicillin and sitafloxacin. However, conventional regimens comprising twice-daily doses (bid) of proton pump inhibitors (PPIs) are generally insufficient for maintaining the required gastric acid secretion for 24 h for successful eradication in all H. pylori-positive patients. Further, the increasing prevalence of CLR-resistant strains with each year has led to a decrease in eradication rates of first-line PPI- and CLR-containing therapies in developed countries, including Japan. In 2015, the potassium-competitive acid blocker vonoprazan (VPZ) became clinically available in Japan. VPZ competitively inhibits H⁺/K⁺-ATPase activity more potently than PPIs (e.g., omeprazole, lansoprazole, rabeprazole, pantoprazole, and esomeprazole). Therefore, a VPZ-containing H. pylori eradication regimen is expected to increase the eradication rate compared with conventional regimens containing a standard dose of PPI. In fact, a recent meta-analysis that investigated the efficacy of first-line eradication therapy showed that a VPZ-containing regimen achieved a higher eradication rate than a PPI-containing regimen. While the Maastricht V/Florence Consensus Report recommends selecting a bismuth or non-bismuth quadruple therapy and concomitant therapy for patients living in areas with high prevalence of CLR resistance, a VPZ-containing regimen demonstrates effectiveness for patients infected with CLR-resistant strains and patients living in areas where the prevalence of CLR-resistant strains is >15%. As a next step, studies are needed to determine the factors affecting the clinical outcome of VPZ-containing therapy and optimal VPZ-containing alternative regimens for tailored treatments. In this review, we summarize the advantages and disadvantages of VPZ in H. pylori eradication therapy.

Helicobacter pylori infections in Ethiopia; prevalence and associated factors: a systematic review and meta-analysis

BACKGROUND

Helicobacter pylori (H.pylori) infections are prevalent and recognized as major cause of gastrointestinal diseases in Ethiopia. However, Studies conducted on the prevalence, risk factors and other clinical forms of H.pylori on different population and geographical areas are reporting conflicting results. Therefore, this review was conducted to estimate the pooled prevalence of H.pylori infections and associated factors in Ethiopia.

METHODS

PubMed, Embase, Google scholar, and Ethiopian Universities' repositories were searched following the Preferred Items for Systematic review and Meta-analysis (PRISMA) guideline. The quality of included studies was assessed using the Newcastle-Ottawa Scale in meta-analysis. Heterogeneity between studies was assessed using Cochrane Q test and I2 test statistics based on the random effects model. Comprehensive meta-analysis (CMA 2.0) and Review Manager (RevMan 5.3) were employed to compute the pooled prevalence and summary odds ratios of factors associated with of H.pylori infection.

RESULTS

Thirty seven studies with a total of 18,890 participants were eligible and included in the analysis. The overall pooled prevalence of H.pylori infection was 52.2% (95% CI: 45.8-58.6). In the subgroup analysis by region, the highest prevalence was found in Somalia (71%; 95% CI: 32.5-92.6) and the lowest prevalence was reported in Oromia (39.9%; 95% CI: 17.3-67.7). Absence of hand washing after toilet (OR = 1.8, 95% CI; 1.19-2.72), alcohol consumption (OR = 1.34, 95% CI; 1.03-1.74) and gastrointestinal (GI) symptoms (OR = 2.23, 95% CI; 1.59-3.14) were associated with H.pylori infection. The trend of H.pylori infection showed a decreasing pattern overtime from 1990 to 2017 in the meta-regression analysis.

CONCLUSION

The prevalence of H.pylori infection remains high; more than half of Ethiopians were infected. Although the trend of infection showed a decreasing pattern; appropriate use of eradication therapy, health education primarily to improve knowledge and awareness on the transmission dynamics of the bacteria, behavioral changes, adequate sanitation, population screening and diagnosis using multiple tests are required to reduce H.pylori infections. Recognizing the bacteria as a priority issue and designing gastric cancer screening policies are also recommended.

Prevalence of Antibiotic Resistance in Helicobacter pylori: A Systematic Review and Meta-analysis in World Health Organization Regions

BACKGROUND & AIMS

In 2017, the World Health Organization (WHO) designated clarithromycin-resistant Helicobacter pylori a high priority for antibiotic research and development. However, there are no clear data on the global distribution of resistance or its clinical effects. We performed a systematic review and meta-analysis to assess the distribution of H pylori resistance to commonly used antibiotics and to measure the association between antibiotic resistance and treatment failure.

METHODS

We searched publication databases for studies that assessed rates of H pylori resistance to clarithromycin, metronidazole, levofloxacin, amoxicillin, or tetracycline. Pooled estimates of primary and secondary resistance and 95% confidence intervals (CIs) were grouped by WHO region. The association between antibiotic resistance and treatment failure was measured by extracting data on treatment efficacy in patients with resistant and susceptible isolates and pooling odds ratios with 95% CIs.

RESULTS

We identified 178 studies, comprising 66,142 isolates from 65 countries. Primary and secondary resistance rates to clarithromycin, metronidazole, and levofloxacin were ≥15% in all WHO regions, except primary clarithromycin resistance in the Americas (10%; 95% CI, 4%-16%) and South-East Asia region (10%; 95% CI, 5%-16%) and primary levofloxacin resistance in the European region (11%; 95% CI, 9%-13%). There was considerable heterogeneity (I2 > 75%) among all analyses-this might have resulted from the grouping of resistance rates by country. Increasing antibiotic resistance was observed in most WHO regions. Resistance to clarithromycin was significantly associated with failure of clarithromycin-containing regimens (odds ratio, 6.97; 95% CI, 5.23-9.28; P < .001).

CONCLUSIONS

Resistance of H pylori to antibiotics has reached alarming levels worldwide, which has a great effect on efficacy of treatment. Local surveillance networks are required to select appropriate eradication regimens for each region.

Current understanding and management of Helicobacter pylori infection: an updated appraisal

In addition to its role in gastric conditions, Helicobacter pylori has been found to contribute to the development of several non-gastric issues in recent years. Eradication therapy is the only effective management strategy to minimize the H. pylori-related gastric cancer and extra-gastric complications. For an effective “test and treat” strategy, diagnosis and therapy are both important. Because the infection is usually asymptomatic, patient selection is a critical issue for timely diagnosis and many clinical and demographic factors should be considered. Clarithromycin and metronidazole resistance rates also need to be considered while eradication therapy is offered. In this report, we discuss the issues which must be taken into account for the correct and timely diagnosis and for the antibiotic therapy-based management of H. pylori infection.

Furazolidone treatment for Helicobacter Pylori infection: A systematic review and meta-analysis

Antibiotic resistance is a major cause of Helicobacter pylori (H. pylori) treatment failures. Because the resistance rate of H. pylori to furazolidone is low, we aimed to assess the efficacy and safety of furazolidone. We searched the PubMed, Web of Science, Cochrane Library, and Embase databases and included randomized controlled trials (RCT) that either compared furazolidone to other antibiotics or changed the administered dose of furazolidone. A total of 18 articles were included in the meta-analysis. According to the intention-to-treat (ITT) analysis, the total eradication rates of furazolidone-containing therapy were superior to those of other antibiotic-containing therapies (relative risk [RR] 1.07, 95% confidence interval [CI] 1.01-1.14) (13 RCTs). Specifically, the eradication rates of furazolidone-containing therapy were better than those for metronidazole-containing therapy (RR 1.10, 95% CI: 1.01-1.21 for ITT). The eradication rate of furazolidone-containing bismuth-containing quadruple therapy was 92.9% (95% CI: 90.7%-95.1%) (PP). In addition, a higher daily dose of furazolidone increased the eradication rate (RR 1.17, 95% CI: 1.05-1.31). And the incidence of some adverse effects, such as fever and anorexia, was higher in the furazolidone group than in the control group, the overall incidences of total side effects and severe side effects showed no significant differences between the groups. Furazolidone-containing treatments could achieve satisfactory eradication rates and did not increase the incidence of total or severe adverse effects, but the incidence of milder side effects, such as fever and anorexia, should be considered when prescribing furazolidone-containing treatments to patients.

A systematic review and meta-analysis of genotypic methods for detecting antibiotic resistance in Helicobacter pylori

BACKGROUND

Antibiotic susceptibility testing is essential for tailored treatments to cure Helicobacter pylori (H. pylori) infection. However, phenotypic methods have some limitations.

OBJECTIVES

To evaluate the feasibility of genotypic detection methods compared with phenotypic detection methods using samples taken from H. pylori-infected patients.

METHODS

Literature searches were conducted in the following databases (from January 2000 to November 2016): PubMed, Embase, the Cochrane Library, and Web of Science. A meta-analysis and systematic review was performed for studies that compared genotypic methods with phenotypic methods for the detection of H. pylori antibiotic susceptibility.

RESULTS

This meta-analysis showed that the pooled sensitivity, specificity, and diagnostic odds ratio (DOR) for the A2142G/C and/or A2143G combination for the detection of clarithromycin resistance in the strain samples were 0.97 (95% CI: 0.94-0.99), 1.00 (95% CI: 0.99-1.00), and 13 742 (95% CI: 1708-110 554), respectively. The pooled sensitivity, specificity, and DOR for the A2142G/C and/or A2143G combination for the detection of clarithromycin resistance in biopsy samples were 0.96 (95% CI: 0.90-0.99), 0.96 (95% CI: 0.91-0.99), and 722 (95% CI: 117-4443), respectively. The summarized sensitivity, specificity, and DOR value for the ability of the genotypic methods to detect quinolone resistance in biopsy specimens were 0.97 (95% CI: 0.87-0.99), 0.99 (95% CI: 0.92-1.00), and 6042 (95% CI: 486-75 143), respectively.

CONCLUSION

The genotypic detection methods were reliable for the diagnosis of clarithromycin and quinolone resistance in the strain and biopsy specimens. The A2142G/C and/or A2143G combination had the best sensitivity and specificity for the detection of clarithromycin resistance.

Review: A Japanese population-based meta-analysis of vonoprazan versus PPI for Helicobacter pylori eradication therapy: Is superiority an illusion?

BACKGROUND

Vonoprazan (VPZ) is a novel acid suppressant that has been used in Helicobacter pylori (H. pylori) eradication therapies in recent years. However, the efficacy and safety of VPZ vs proton-pump inhibitor (PPI) in H. pylori eradication therapies remain controversial.

OBJECTIVE

To perform a meta-analysis in order to assess the efficacy and safety of VPZ vs PPI for H. pylori eradication.

MATERIALS AND METHODS

The PubMed, EMBASE, and Cochrane Library databases were searched up to July 10, 2017, for relevant randomized controlled trials (RCTs) and nonrandomized clinical studies (NRCTs). The pooled eradication rate (ER) and pooled occurrence rates of adverse events were used to compare the efficacy and safety of VPZ - and PPI-containing regimens.

RESULT

A total of 14 studies with 14 636 patients were included in this meta-analysis. The results showed that the pooled ER of VPZ -containing regimens was much higher than that of PPI-containing regimens when used as first-line therapies. This difference was significant for both intention-to-treat (85.1% vs 68.0%, P < .00001) and per-protocol analyses (89.0% vs 74.2%, P < .00001). Moreover, subgroup analysis indicated significant superiority of VPZ in both patients with clarithromycin-resistant strains (81.5% vs 40.9%, P < .00001) and those with clarithromycin-susceptible strains (94.9% vs 89.6%, P = .006). However, VPZ did not show superiority to PPI as part of a second-line triple therapy based on both intention-to-treat (83.4% vs 82.0%, P = .79) and per-protocol analyses (89.3% vs 90.1%, P = .06). Finally, RCT subgroup analysis showed the safety of VPZ -containing regimens to be better than PPI-containing regimens (26.4% vs 33.3%, P = .008), whereas there was no significant difference in this regard for the NRCT subgroup analysis (5.7% vs 4.7%, P = .08).

CONCLUSIONS

The efficacy of VPZ is superior to PPI in first-line H. pylori triple eradication therapies but not in second-line therapies. The safety of VPZ -containing regimens appears to be equal or even superior to that of PPI. However, most reports included in this study had low levels of evidence. Hence, adequate and high-quality RCTs will be needed to support our results.

Treatment of Helicobacter pylori infection 2017

This review summarizes important studies regarding Helicobacter pylori therapy published from April 2016 to April 2017. The main themes that emerge involve studies assessing the efficacy of bismuth and nonbismuth quadruple regimens. While in recent years, much of the emphasis on the use of bismuth has focussed on its utility in a second-line setting, an increasing number of studies this year have shown excellent efficacy in first-line therapy. The efficacy of bismuth as a second-line after sequential and concomitant therapy was particularly noteworthy. Antibiotic resistance was more intensely studied this year than for a long time, and definite trends are presented regarding an increase in resistance, including the fact that clarithromycin resistance in particular is now at a level where the continued use of clarithromycin triple therapy first-line as a mainstream treatment is not recommended. Another exciting trend to emerge this year is the utility of vonoprazan as an alternative to PPI therapy, especially in resistant and difficult-to-treat groups.

Noninvasive molecular analysis of Helicobacter pylori: Is it time for tailored first-line therapy?

The main problem of Helicobacter pylori (H. pylori) infection management is linked to antibiotic resistances. This phenomenon has grown in the last decade, inducing a dramatic decline in conventional regimen effectiveness. The causes of resistance are point mutations in bacterial DNA, which interfere with antibiotic mechanism of action, especially clarithromycin and levofloxacin. Therefore, international guidelines have recently discouraged their use in areas with a relevant resistance percentage, suggesting first-line schedules with expected high eradication rates, i.e., bismuth containing or non-bismuth quadruple therapies. These regimens require the daily assumption of a large number of tablets. Consequently, a complete adherence is expected only in subjects who may be motivated by the presence of major disorders. However, an incomplete adherence to antibiotic therapies may lead to resistance onset, since sub-inhibitory concentrations could stimulate the selection of resistant mutants. Of note, a recent meta-analysis suggests that susceptibility tests may be more useful for the choice of first than second-line or rescue treatment. Additionally, susceptibility guided therapy has been demonstrated to be highly effective and superior to empiric treatments by both meta-analyses and recent clinical studies. Conventional susceptibility test is represented by culture and antibiogram. However, the method is not available everywhere mainly for methodology-related factors and fails to detect hetero-resistances. Polymerase chain reaction (PCR)-based, culture-free techniques on gastric biopsy samples are accurate in finding even minimal traces of genotypic resistant strains and hetero-resistant status by the identification of specific point mutations. The need for an invasive endoscopic procedure has been the most important limit to their spread. A further step has, moreover, been the detection of point mutations in bacterial DNA fecal samples. Few studies on clarithromycin susceptibility have shown an overall high sensitivity and specificity when compared with culture or PCR on gastric biopsies. On these bases, two commercial tests are now available although they have shown some controversial findings. A novel PCR method showed a full concordance between tissue and stool results in a preliminary experience. In conclusion, despite poor validation, there is increasing evidence of a potential availability of noninvasive investigations able to detect H. pylori resistances to antibiotics. These kinds of analysis are currently at a very early phase of development and caution should be paid about their clinical application. Only further studies aimed to evaluate their sensitivity and specificity will afford novel data for solid considerations. Nevertheless, noninvasive molecular tests may improve patient compliance, time/cost of infection management and therapeutic outcome. Moreover, the potential risk of a future increase of resistance to quadruple regimens as a consequence of their use on large scale and incomplete patient adherence could be avoided.