Is antimicrobial susceptibility testing necessary before second-line treatment for Helicobacter pylori infection?

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

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

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.

High-dose dual therapy versus culture-based susceptibility-guided therapy as a rescue regimen for Helicobacter pylori infection: a randomized controlled trial

BACKGROUND

Although the Maastricht VI/Florence consensus report recommended high-dose proton pump inhibitor-amoxicillin dual therapy as possible rescue therapy for Helicobacter pylori infection, clinical evidence of its efficacy was lacking.

OBJECTIVES

To compare the efficacy, safety, patient compliance, and cost between high-dose dual therapy (HDDT) and culture-based susceptibility-guided therapy (CB-SGT) as a rescue regimen for H. pylori infection.

DESIGN

A single-center, open-label, randomized controlled clinical trial.

METHODS

In all, 146 patients with a history of eradication failure were enrolled and randomly assigned to receive HDDT or CB-SGT. HDDT consisted of esomeprazole 20 mg and amoxicillin 750 mg, both given four times per day (qid). CB-SGT consisted of esomeprazole 20 mg twice daily (bid), amoxicillin 1000 mg bid plus clarithromycin 500 mg bid, metronidazole 400 mg bid, or levofloxacin 500 mg daily (qd) for sensitive patients, in that order. For patients with triple resistance, a bismuth-containing regimen with a high dose of metronidazole was chosen, including esomeprazole 20 mg bid, bismuth 220 mg bid, amoxicillin 1000 mg bid, and metronidazole 400 mg qid. All regimens were given for 14 days.

RESULTS

The eradication H. pylori rates achieved with HDDT in the intention-to-treat (ITT), per-protocol, and modified ITT analyses were all 84.9% [62/73, 95% confidence interval (CI): 76.5-93.9%], compared with 83.6% (61/73, 95% CI: 74.9-92.3%), 84.7% (61/72, 95% CI: 76.2-93.2%), and 84.7% (61/72, 95% CI: 76.2-93.2%) with CB-SGT, respectively. For patients with CYP2C19 polymorphisms of intermediate/poor metabolizers, the eradication rates of HDDT and CB-SGT were 90.70% (39/43, 95% CI: 77.86-97.41%) and 84.21% (32/38, 95% CI: 68.75-93.98%), respectively. The difference between groups was 6.49% (95% CI: -8.00% to 20.97%), and the non-inferiority p value was 0.0128. For patients with a treatment interval of more than 3 months, the eradication rates of the two regimens reached 88.71% (95% CI: 78.11-95.34%) and 71.97% (95% CI: 70.02-90.64%). The difference between groups was 6.74% (95% CI: -5.71% to 19.20%), with a non-inferiority p value of 0.0042. Patient adherence was high in both groups. The HDDT had a lower cost and rate of side effects (p < 0.001) compared with CB-SGT.

CONCLUSIONS

HDDT can reach an eradication rate of 85% in treatment-experienced patients of H. pylori infection and 91% in patients with CYP2C19 polymorphisms of intermediate/poor metabolizers, with good compliance, lower side effects and costs, and less use of antibiotics. In conclusion, HDDT offers an effective rescue regimen for H. pylori infection.

REGISTRATION

This clinical trial was registered at the Chinese Clinical Trail Registry (trail registration number: ChiCTR1900025044).

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

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

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

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

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

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.

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

BACKGROUND AND AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Effectiveness of Helicobacter pylori eradication established on the basis of examination of antibiotic resistance of the bacteria

INTRODUCTION

The treatment of Helicobacter pylori (HP) tends to be empirical despite a high number of failures (over 20%). The efficacy of eradication therapies is declining, reaching in some countries 60%, which correlates inversely with the growing drug resistance of the bacteria.

AIM

Given the frequent inefficacy of the hitherto proposed treatment schemes for HP infection, an attempt was made to assess the efficacy of a therapy based on the antibiotic resistance of the cultured bacteria, and to analyse factors with possible contribution to the inefficacy of HP eradication treatment.

MATERIAL AND METHODS

The study covered patients from one region of Central Poland in the years 2005-2015. The total material for bacteriological assessment was collected from 154 patients who had previously been subject to HP eradication treatment at least two times, including 80 women and 74 men, reporting subsequently to the Clinic.

RESULTS

The efficacy of the antibiogram-based treatment was merely 65.62%. A low, but slightly higher than expected, resistance to amoxicillin (3.48%) and tetracycline (2.27%), as well as to clarithromycin (27.27%) and metronidazole (70.69%), was established.

CONCLUSIONS

In Polish patients resistance to clarithromycin and metronidazole of HP is high and becoming increasingly resistant; however, we found low bacterial resistance to tetracycline.

Antibiotic susceptibility, heteroresistance, and updated treatment strategies in Helicobacter pylori infection

In this review, we discuss the problem of antibiotic resistance, heteroresistance, the utility of cultures and antibiotic susceptibility tests in Helicobacter pylori (Hp) eradication, as well as the updated treatment strategies for this infection. The prevalence of antibiotic resistance is increasing all over the world, especially for metronidazole and clarithromycin, because of their heavy use in some geographical areas. Heteroresistance (simultaneous presence of both susceptible and resistant strains in different sites of a single stomach) is another important issue, as an isolate could be mistakenly considered susceptible if a single biopsy is used for antimicrobial tests. We also examined literature data regarding eradication success rates of culture-guided and empiric therapies. The empiric therapy and the one based on susceptibility testing, in Hp eradication, may depend on several factors such as concomitant diseases, the number of previous antibiotic treatments, differences in bacterial virulence in individuals with positive or negative cultures, together with local antibiotic resistance patterns in real-world settings. Updated treatment strategies in Hp infection presented in the guidelines of the Toronto Consensus Group (2016) are reported. These suggest to prolong eradication therapy up to 14 days, replacing the old triple therapy with a quadruple therapy based on proton pump inhibitor (PPI), bismuth, metronidazole, and tetracycline for most of the patients, or as an alternative quadruple therapy without bismuth, based on the use of PPI, amoxicillin, metronidazole, and clarithromycin. The new drug vonoprazan, a first-in-class potassium-competitive acid blocker recently approved in Japan, is also considered to be a promising solution for Hp eradication, even for clarithromycin-resistant strains. Furthermore, there is growing interest in finding new therapeutic strategies, such as the development of vaccines or the use of natural resources, including probiotics, plants, or nutraceuticals.

Usefulness of vonoprazan, a potassium ion-competitive acid blocker, for primary eradication of Helicobacter pylori

AIM

To investigate usefulness of triple therapy with vonoprazan, a potassium ion-competitive acid blocker and antibiotics, for Helicobacter pylori (H. pylori) eradication.

METHODS

The H. pylori eradication rate was examined in 2507 patients (2055 undergoing primary eradication and 452 undergoing secondary eradication, excluding patients with subtotal gastrectomy) at the Japanese Red Cross Kyoto Daiichi Hospital from March 2013 to September 2015. For patients treated from March 2013 to February 2015, a proton pump inhibitor (PPI) was used to reduce acid secretion, while vonoprazan was used after March 2015. The success rates of the 2 regimens (PPI + amoxicillin + clarithromycin/metronidazole, or vonoprazan + amoxicillin + clarithromycin/metronidazole) were compared.

RESULTS

The success rate of primary H. pylori eradication was significantly higher in the vonoprazan group. When stratified by the underlying disease, a significant increase of the H. pylori eradication rate was observed in patients with chronic gastritis. A significantly lower H. pylori eradication rate was observed in younger patients compared to older patients in the PPI group, but there was no difference according to age in the vonoprazan group. On the other hand, the success rate of secondary eradication was similar at approximately 90% in both groups.

CONCLUSION

Vonoprazan is very useful for primary eradication of H. pylori, and may become a first-line acid secretion inhibitor instead of PPIs.

Systematic review: third-line susceptibility-guided treatment for Helicobacter pylori infection

BACKGROUND

Susceptibility-guided therapies (SGTs) have been proposed as preferable to empirical rescue treatments after two treatment failures. The aim of this study was to perform a systematic review and meta-analysis evaluating the effectiveness and efficacy of SGT as third-line therapy.

METHODS

A systematic search was performed in multiple databases. Studies reporting cure rates of Helicobacter pylori with SGT in third-line therapy were selected. A qualitative analysis describing the current evidence and a pooled mean analysis summarizing the cure rates of SGT in third-line therapy was performed.

RESULTS

No randomized controlled trials or comparative studies were found. Four observational studies reported cure rates with SGT in third-line treatment, and three studies which mixed patients with second- and third-line treatment also reported cure rates with SGT. The majority of the studies included the patients when culture had been already obtained, and so the effectiveness of SGT and empirical therapy has never been compared. A pooled mean analysis including four observational studies (283 patients) showed intention-to-treat and per-protocol eradication rates with SGT of 72% (95% confidence interval 56-87%; I(2) : 92%) and 80% (95% confidence interval 71-90%; I(2) : 80%), respectively.

CONCLUSIONS

SGT may be an acceptable option as rescue treatment. However, cure rates are, at best, moderate and this approach has never been compared with a well-devised empirical therapy. The evidence in favor of SGT as rescue therapy is currently insufficient to recommend its use.

Tailored Therapy Versus Empiric Chosen Treatment for Helicobacter pylori Eradication: A Meta-Analysis

Although various regimens are empirically accepted for Helicobacter pylori eradication, the efficacy might be declined by multiple individual factors. The necessity of a personalized eradication therapy still remains controversial. The aim of the study was to compare tailored therapy with empiric chosen regimens. Databases of PUBMED, EMBASE, and MEDLINE were searched for eligible studies, published up to October 2015. All relevant controlled clinical trials were included. A random-effect model was applied to compare pooled relative risk (RR) with related 95% confidence intervals (CIs).Thirteen controlled clinical trials integrating 3512 participants were assessed. Overall, the pooled eradication rates of tailored groups were higher than those of empiric ones (intention-to-treat: RR = 1.16, 95% CI 1.10-1.22; preprotocol: RR = 1.14, 95% CI 1.08-1.21). In subgroup analysis, tailored therapy was superior to 7-day standard triple therapy (RR = 1.22, 95% CI 1.16-1.29) and bismuth-quadruple therapy (RR = 1.14, 95% CI 1.07-1.22) on eradication rates; first-line tailored therapy achieved higher eradication rates than first-line empirical regimens (pooled RR = 1.18, 95%CI 1.14-1.22), whereas tailored rescue regimen showed no difference with empirical ones (pooled RR = 1.16, 95% CI 0.96-1.39). Moreover, among different tailored designs, susceptibility-guided tailored therapy obtained higher eradication rates than empiric groups, independent of CYP2C19 genotype detection (with CYP: RR = 1.16, 95% CI 1.09-1.23; without CYP: RR = 1.14, 95% CI 1.01-1.28). Both molecular test-based and culture-based tailored groups were better on eradication rates than empiric groups (molecular: RR = 1.23, 95% CI 1.11-1.35; culture: RR = 1.13, 95% CI 1.06-1.20). Compared with empiric chosen treatments, tailored therapy is a better alternative for H pylori eradication.

Systematic review and meta-analysis: susceptibility-guided versus empirical antibiotic treatment for Helicobacter pylori infection

BACKGROUND

The cure rate of standard triple therapy for Helicobacter pylori infection is unacceptably low. Susceptibility-guided therapies (SGTs) have been proposed as an alternative to standard empirical treatments. The aim of this study was to perform a systematic review and meta-analysis evaluating the efficacy of SGTs.

METHODS

A systematic search was performed in multiple databases. Randomized controlled trials comparing cure rates of SGTs versus those of empirical therapy were selected and analysed separately for first- and second-line treatments. A meta-analysis was performed using risk ratio (RR) and number needed to treat (NNT) to measure the effect.

RESULTS

Twelve studies were included in the meta-analysis. In first-line treatment, SGT was more efficacious than empirical 7-10 day triple therapy (RR 1.16, 95% CI 1.10-1.23, I (2) = 33%; NNT = 8). Most studies used a 7-10 day triple therapy and randomized the patients after endoscopy and/or culture, thus precluding the comparison of SGT versus non-invasive testing and empirical treatment in clinical practice. For second-line therapy, only four studies were found. Results were highly heterogeneous and no significant differences were found (RR 1.11, 95% CI 0.82-1.51, I (2) = 87%).

CONCLUSIONS

Once endoscopy and culture have been performed, SGT is superior to empirical 7 or 10 day triple therapy for first-line treatment. Further studies are needed to evaluate the effectiveness of SGT in clinical practice, especially when compared with currently recommended first-line quadruple therapies.

Ten-year trend of the cumulative Helicobacter pylori eradication rate for the 'Japanese eradication strategy'

BACKGROUND/AIMS

In Japan, a systematic eradication strategy for Helicobacter pylori has been constructed, and consists of a proton pump inhibitor/amoxicillin and clarithromycin (PPI/AC) therapy as the first-line regimen and proton pump inhibitor/amoxicillin and metronidazole (PPI/AM) therapy as the second-line regimen. The cumulative rate of H. pylori eradication has not been reported. Therefore, we investigated the annual and cumulative eradication rate to verify the efficacy of the 'Japanese eradication strategy'.

METHODS

Patients who received first-line PPI/AC therapy and, if necessary, second-line PPI/AM therapy between 2000 and 2009 were retrospectively analyzed. The annual cumulative eradication rate was calculated. Data were subjected to intention-to-treat analysis.

RESULTS

PPI/AC was administered to 1973 patients (male n = 1,162, female n = 811; mean age: 55.8 years, range: 15–87), and 250 patients received PPI/ AM. The eradication rate for the PPI/AC regimen was 65.3%, and it gradually but significantly decreased over 10 years (p < 0.05). For the PPI/AM regimen, the eradication rate was 84.0%, with no change in the annual eradication rate. The cumulative eradication rates were 76.0% in intention-to-treat analysis and 98.4% in per-protocol analysis, respectively, which provided a consistent annual eradication rate without decreases in effectiveness.

CONCLUSION

Although the eradication rate for the first-line PPI/AC regimen decreased over time, the 'Japanese eradication strategy' provided a sufficient eradication rate.

A review of rescue regimens after clarithromycin-containing triple therapy failure (for Helicobacter pylori eradication)

INTRODUCTION

Helicobacter pylori infection is generally treated with therapies that include a proton pump inhibitor (PPI) and, at least, two antibiotics being clarithromycin one of the most used. Antibiotic resistance, mainly to clarithromycin, seems to be increasing in many geographical areas, and this factor is considered a main cause leading to a treatment failure when the later therapies contain this antibiotic again. As clarithromycin is a key antibiotic in the eradication of H. pylori, the election of the rescue treatment is a matter of debate.

AREAS COVERED

The aim of this study is to systematically review the efficacy of the second-line rescue therapies after the failure of a first-line clarithromycin-containing regimen, and to link this information with the previous first-line treatment. Also, authors performed meta-analyses and inverse variance analyses with studies that met the inclusion criteria: first-line treatment must specify type and dosage; diagnosis and eradication confirmation must be performed by generally accepted tests; and second-line treatment must not be assigned depending on the antibiotic susceptibility or resistance.

EXPERT OPINION

In a routine clinical practice setting, the most adequate second-line treatment consists in a 10-day regimen of levofloxacin- amoxicillin-PPI given twice daily, unless regional or new data show high quinolone resistance. Other good options are the bismuth quadruple regimen and a metronidazole-amoxicillin-PPI therapy.

Comparison of 10 day bismuth quadruple therapy with high-dose metronidazole or levofloxacin for second-line Helicobacter pylori therapy: a randomized controlled trial

OBJECTIVES

This prospective study was designed to compare the efficacies of levofloxacin-containing and high-dose metronidazole-containing quadruple therapies after failure of standard triple therapies.

METHODS

A total of 150 Helicobacter pylori-infected patients were enrolled in our study and randomly assigned to levofloxacin-containing quadruple therapy (EBTL group) (40 mg of esomeprazole twice daily, 300 mg of bismuth subcitrate four times daily, 500 mg of tetracycline four times daily and 500 mg of levofloxacin once daily for 10 days) (n = 76) or high-dose metronidazole-based quadruple therapy (EBTM group) (40 mg of esomeprazole twice daily, 300 mg of bismuth subcitrate four times daily, 500 mg of tetracycline four times daily and 500 mg of metronidazole four times daily for 10 days) (n = 74). Follow-up endoscopy or urea breath test was done 16 weeks later to assess the treatment response. Patients' responses, CYP2C19 genotypes and antibiotic resistances were also examined. All participants, caregivers and those assessing the outcomes were blinded to group assignment.

RESULTS

Intention-to-treat analysis revealed that both groups showed similar eradication rates: EBTL, 78.9% (60/76) (95% CI 69.7%-88.1%) and EBTM, 79.7% (59/74) (95% CI 70.5%-88.7%) [risk ratio (RR) 0.97, 95% CI 0.44-2.14]. Per-protocol results were EBTL = 87.0% (60/69) (95% CI 79.4%-94.9%) and EBTM = 90.8% (59/65) (95% CI 83.8%-97.8%) (RR 0.68, 95% CI 0.23-2.0). We did not find significant differences in compliance (RR 0.5, 95% CI 0.54-2.3) and adverse events (RR 1.11, 95% CI 0.54-2.3) between the two groups. Logistic regression analysis showed that only compliance was an important predictor for eradication failure. CYP2C19 polymorphism did not influence the eradicating effect.

CONCLUSIONS

The 10 day bismuth quadruple therapies with high-dose metronidazole or levofloxacin were effective even in areas with high resistance. These two therapies were equally safe and tolerated. Besides this, the metronidazole-containing therapy was cheaper. So it is persuasive that high-dose metronidazole-containing quadruple therapy could be a good choice for second-line H. pylori eradication in areas with high resistance.

Rescue Therapy for Helicobacter pylori Infection 2012

Helicobacter pylori infection is the main cause of gastritis, gastroduodenal ulcer disease, and gastric cancer. After 30 years of experience in H. pylori treatment, however, the ideal regimen to treat this infection has still to be found. Nowadays, apart from having to know well first-line eradication regimens, we must also be prepared to face treatment failures. In designing a treatment strategy, we should not only focus on the results of primary therapy alone but also on the final-overall-eradication rate. The choice of a "rescue" treatment depends on which treatment is used initially. If a first-line clarithromycin-based regimen was used, a second-line metronidazole-based treatment (quadruple therapy) may be used afterwards, and then a levofloxacin-based combination would be a third-line "rescue" option. Alternatively, it has recently been suggested that levofloxacin-based "rescue" therapy constitutes an encouraging 2nd-line strategy, representing an alternative to quadruple therapy in patients with previous PPI-clarithromycin-amoxicillin failure, with the advantage of efficacy, simplicity and safety. In this case, quadruple regimen may be reserved as a 3rd-line "rescue" option. Even after two consecutive failures, several studies have demonstrated that H. pylori eradication can finally be achieved in almost all patients if several "rescue" therapies are consecutively given.

A clinician's guide to salvage therapy for persistent Helicobacter pylori infection

Since its discovery in 1982, Helicobacter pylori has been established as a common cause of gastritis and peptic ulcer disease. H pylori infection is also closely associated with several gastric malignancies and has consequently been designated a human carcinogen. As these associations have become increasingly recognized and pursued, a growing challenge facing today's clinicians is the management of patients with persistent H pylori despite previous attempts to treat the infection. In developed countries, the most popular treatment regimen remains traditional triple therapy consisting of a proton pump inhibitor, clarithromycin, and amoxicillin for 7 to 14 days. Unfortunately, eradication rates with traditional triple therapy are disappointing, with infection persisting in as many as 25% of those treated. This article addresses the management of patients with persistent H pylori infection, including indications for confirmatory testing, reasons for treatment failure, and established and emerging salvage regimens for patients with persistent infection.

Rabeprazole can overcome the impact of CYP2C19 polymorphism on quadruple therapy

OBJECTIVES

The prospective study was designed to clarify the impact of CYP2C19 on quadruple therapies and survey the efficacies of rabeprazole-based quadruple therapy for Helicobacter pylori infection after failure of standard triple therapies.

PATIENTS AND METHODS

From January 2007 to March 2009, 1055 H. pylori-infected patients received standard triple regimens (proton-pump inhibitor (PPI), clarithromycin, and amoxicillin). Helicobacter pylori eradication was achieved in 865 (81.9%) subjects. One hundred ninety eradication-failure patients were enrolled and randomly assigned to receive a 7-day eradication therapy. Ninety-six patients were treated with esomeprazole-based quadruple rescue therapies (EB), while 94 patients were treated with rabeprazole-based quadruple rescue therapies (RB). Follow-up endoscopy was done 16 weeks later to assess the treatment response. Patients' responses, CYP2C19 genotypes, and antibiotics resistances were also examined.

RESULTS

Intention-to-treat analysis revealed that RB had better eradication rates than EB (EB: 72.9%; 95% CI: 64.9-80.9% and RB: 78.7%; 95% CI 72.5-84.9%) (p value = .543). Per-protocol results were EB = 75.3%; 95% CI: 70.3-80.3% and RB = 85.1%; 95% CI: 80.6-89.6% (p value = .0401). Both regimens had similar compliance (p value = 0.155) and adverse events (p value = 0.219). We also surveyed those patients without resistance of any antibiotics. RB still showed better outcome than EB. Our data showed that esomeprazole-based regimen and CYP2C19 Hom EM genotype were important predictors for eradication failure.

CONCLUSIONS

In quadruple therapy, rabeprazole-based regimens had better efficacy than esomeprazole-based regimens. CYP2C19 polymorphism also played an important role in quadruple therapy. It seems advisable to change PPI to rabeprazole in second-line quadruple therapy.

Guidelines for the management of Helicobacter pylori infection in Japan: 2009 revised edition

BACKGROUND

Over the past few years, the profile of Helicobacter pylori infection has changed in Japan. In particular, the relationship between H. pylori and gastric cancer has been demonstrated more clearly. Accordingly, the committee of the Japanese Society for Helicobacter Research has revised the guidelines for diagnosis and treatment of H. pylori infection in Japan.

MATERIALS AND METHODS

Four meetings of guidelines preparation committee were held from July 2007 to December 2008. In the new guidelines, recommendations for treatment have been classified into five grades according to the Minds Recommendation Grades, while the level of evidence has been classified into six grades. The Japanese national health insurance system was not taken into consideration when preparing these guidelines.

RESULTS

Helicobacter pylori eradication therapy achieved a Grade A recommendation, being useful for the treatment of gastric or duodenal ulcer, for the treatment and prevention of H. pylori-associated diseases such as gastric cancer, and for inhibiting the spread of H. pylori infection. Levels of evidence were determined for each disease associated with H. pylori infection. For the diagnosis of H. pylori infection, measurement of H. pylori antigen in the feces was added to the tests not requiring biopsy. One week of proton-pump inhibitor-based triple therapy (including amoxicillin and metronidazole) was recommended as second-line therapy after failure of first-line eradication therapy.

CONCLUSION

The revised Japanese guidelines for H. pylori are based on scientific evidence and avoid the administrative restraints that applied to earlier versions.

Is antimicrobial susceptibility testing necessary before first-line treatment for Helicobacter pylori infection? Meta-analysis of randomized controlled trials

BACKGROUND

With the wide use of antibiotics, antibiotic-resistant Helicobacter pylori strains are becoming increasingly prevalent. It has been hypothesized that culture-guided therapy might help to increase treatment success. But the effects and the costs still remain controversial.

AIMS

To systematically review the efficacy and the cost of culture-guided triple therapy, compared to standard triple regimen for first-line treatment of Helicobacter pylori infection.

METHODS

A search of the Cochrane Library, PubMed, EMBASE, Science Citation Index Expanded and CBM was performed. Randomized controlled trials comparing culture-guided triple therapy to standard triple therapy in the first-line treatment of Helicobacter pylori infection were selected for meta-analysis. Relative risk was used as a measure of the effect of two regimens mentioned above with a fixed-effects model using the methods of DerSimonian and Laird.

RESULTS

Five randomized controlled trials totaling 701 patients were included. The meta-analysis showed that culture-guided triple therapy was superior referring to a higher eradication rate from intention-to-treat analyses (RR, 0.84; 95% CI,0.77, 0.90; p<0.00001) and a lower overall cost.

CONCLUSION

Culture-guided triple therapy was more effective than standard triple therapy for first-line treatment of Helicobacter pylori infection. Based on the only paper focused on the overall cost, the culture-guided triple therapy was also more cost saving. Antimicrobial susceptibility testing is necessary before first-line treatment for Helicobacter pylori infection.

Second-line rescue therapy of helicobacter pylori infection

Helicobacter pylori infection is the main known cause of gastritis, gastroduodenal ulcer disease and gastric cancer. After more than 20 years of experience in H. pylori treatment, however, the ideal regimen to treat this infection has still to be found. Nowadays, apart from having to know well first-line eradication regimens, we must also be prepared to face treatment failures. Therefore, in designing a treatment strategy we should not focus on the results of primary therapy alone, but also on the final (overall) eradication rate. The choice of a 'rescue' treatment depends on which treatment is used initially. If a first-line clarithromycin-based regimen was used, a second-line metronidazole-based treatment (quadruple therapy) may be used afterwards, and then a levofloxacin-based combination would be a third-line 'rescue' option. Alternatively, it has recently been suggested that levofloxacin-based 'rescue' therapy constitutes an encouraging second-line strategy, representing an alternative to quadruple therapy in patients with previous PPI-clarithromycin-amoxicillin failure, with the advantage of efficacy, simplicity and safety. In this case, quadruple regimen may be reserved as a third-line 'rescue' option. Finally, rifabutin-based 'rescue' therapy constitutes an encouraging empirical fourth-line strategy after multiple previous eradication failures with key antibiotics such as amoxicillin, clarithromycin, metronidazole, tetracycline, and levofloxacin. Even after two consecutive failures, several studies have demonstrated that H. pylori eradication can finally be achieved in almost all patients if several 'rescue' therapies are consecutively given. Therefore, the attitude in H. pylori eradication therapy failure, even after two or more unsuccessful attempts, should be to fight and not to surrender.

Impact of quadruple regimen of clarithromycin added to metronidazole-containing triple therapy against Helicobacter pylori infection following clarithromycin-containing triple-therapy failure

BACKGROUND

The establishment of an optimal second-line regimen for Helicobacter pylori infection is required. Although quadruple therapy should overcome resistance to either clarithromycin or metronidazole, the effects of a quadruple regimen in second-line therapy are unknown. This study aims to evaluate the efficacy of triple therapy composed of proton pump inhibitor/amoxicillin plus metronidazole with the combined additive effects of clarithromycin as a second-line quadruple therapy against H. pylori infection.

MATERIALS AND METHODS

Participants were 104 patients in whom first-line therapy containing proton pump inhibitor-amoxicillin-clarithromycin failed. Before starting second-line therapy, patients underwent endoscopy to obtain H. pylori strain for antibiotic susceptibility tests. Patients were randomized to receive rabeprazole (10 mg), amoxicillin (750 mg), and metronidazole (250 mg), either with clarithromycin (200 mg; RAMC group) or without (RAM group); all treatments were administered twice daily for 7 days. H. pylori eradication was confirmed by (13)C-urea breath tests performed 2 to 3 months post-therapy.

RESULTS

As shown by intention-to-treat/per-protocol analyses, the cure rates for H. pylori infection were 88.5%/93.9% and 82.7%/84.3% for the RAMC and RAM groups. Although the study probably had an insufficient power to show a significant difference between the cure rates of the two regimens, the eradication rates showed a clear trend in favor of the RAMC group. There were no severe side-effects in any group.

CONCLUSIONS

In Japan, the RAMC regimen is thought to be a promising alternative strategy for second-line eradication of H. pylori infection.

Identification and molecular characterization of triple- and quadruple-resistant Helicobacter pylori clinical isolates in Germany

OBJECTIVES

The aim of this study was to estimate the frequency of triple- and quadruple-resistant Helicobacter pylori isolated in Germany, to characterize those isolates molecular genetically and to identify risk factors for the development of multiresistance.

METHODS

Antimicrobial susceptibility to metronidazole, clarithromycin, amoxicillin, tetracycline, ciprofloxacin/levofloxacin and rifampicin in 1118 clinical isolates obtained between July 2006 and December 2007 was tested by the Etest method. For patients harbouring triple- or quadruple-resistant strains (n = 169), data on prior eradication therapies and underlying diseases were collected and evaluated. A select number of quadruple- and triple-resistant strains were examined for resistance-mediating mutations in their 23S rRNA, 16S rRNA, gyrA and rpoB genes, respectively.

RESULTS

From 1118 clinical isolates, 13.4% (n = 150) showed phenotypic resistance to metronidazole, clarithromycin and quinolones and 0.9% (n = 10) to metronidazole, clarithromycin and rifampicin; one isolate exhibited resistance to clarithromycin, quinolones and rifampicin. In eight isolates (0.7%), we detected phenotypic quadruple resistance to metronidazole, clarithromycin, quinolones and rifampicin or tetracycline. Triple- and quadruple-resistant strains harboured resistance-associated mutations in their 23S rRNA, 16S rRNA, gyrA or rpoB genes and were nearly exclusively isolated from patients who had already been unsuccessfully treated on multiple occasions.

CONCLUSIONS

We show that more than 15% of H. pylori strains isolated from routine samples in the German National Reference Centre are resistant to three or more antimicrobials and identified prior unsuccessful eradication therapies as a key factor for the development of multiresistance. Our data emphasize the need for further comprehensive surveillance studies monitoring the role of treatment regimens in antimicrobial resistance in H. pylori.

“Rescue” regimens after Helicobacter pylori treatment failure

Helicobacter pylori (H pylori) infection is the main cause of gastritis, gastroduodenal ulcer disease, and gastric cancer. After more than 20 years of experience in H pylori treatment, in my opinion, the ideal regimen to treat this infection is still to be found. Currently, apart from having to know first-line eradication regimens well, we must also be prepared to face treatment failures. Therefore, in designing a treatment strategy we should not focus on the results of primary therapy alone, but also on the final (overall) eradication rate. The choice of a “rescue” treatment depends on which treatment is used initially. If a clarithromycin-based regimen was used initially, a subsequent metronidazole-based treatment (quadruple therapy) may be used afterwards, and then a levofloxacin-based combination would be a third “rescue” option. Alternatively, it has recently been suggested that levofloxacin-based rescue therapy constitutes an encouraging second-line strategy, representing an alternative to quadruple therapy in patients with previous PPI-clarithromycin-amoxicillin failure, with the advantage of efficacy, simplicity and safety. In this case, a quadruple regimen may be reserved as a third-line rescue option. Finally, rifabutin-based rescue therapy constitutes an encouraging empirical fourth-line strategy after multiple previous eradication failures with key antibiotics such as amoxicillin, clarithromycin, metronidazole, tetracycline, and levofloxacin. Even after two consecutive failures, several studies have demonstrated that H pylori eradication can finally be achieved in almost all patients if several rescue therapies are consecutively given. Therefore, the attitude in H pylori eradication therapy failure, even after two or more unsuccessful attempts, should be to fight and not to surrender.

One-week once-daily triple therapy with esomeprazole, moxifloxacin, and rifabutin for eradication of persistent Helicobacter pylori resistant to both metronidazole and clarithromycin

AIM

To investigate a 1-week once-daily triple therapy with esomeprazole, moxifloxacin, and rifabutin for rescue therapy of Helicobacter pylori infection.

METHODS

Consecutive patients (n = 103) with at least one previous treatment failure and H. pylori infection resistant to both metronidazole and clarithromycin were treated with esomeprazole 40 mg, moxifloxacin 400 mg, and rifabutin 300 mg, given once daily for 7 days. Eradication was confirmed by histology and culture. CYP2C19 status was determined by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Intention-to-treat and per-protocol eradication rates were 77.7% (68.4-85.3) and 83.3% (74.4-90.2). Five patients discontinued prematurely (4.8%). Eradication was achieved in 93.1% of poor/intermediate metabolizers and in 78.8% of homozygous extensive metabolizers (p = .14). Eradication rates in patients with one, two, three, and four or more previous failures were 78.3%, 89.6%, 68.6%, and 88.9%, respectively (p = .21). The regimen was effective in seven of nine patients who previously failed quadruple therapy. Post-treatment resistance to moxifloxacin and rifabutin was detected in two (12.5%) and five (31%) patients after treatment failure.

CONCLUSION

Once-daily triple therapy with esomeprazole, moxifloxacin, and rifabutin is a promising, safe, and convenient regimen for rescue therapy of H. pylori infection that may serve as a valuable alternative to quadruple therapy, particularly for patients with intolerance to amoxicillin.

Treatment of Helicobacter pylori

Triple therapy, consisting of two antibiotics, clarithomycin and amoxicillin or metronidazole in combination with a proton pump inhibitor (PPI) has become the first-line option for infection with Helicobacter pylori and has been recommended at several consensus conferences. In clinical practice, approximately 20% of patients will fail to obtain H. pylori eradication with the recommended treatment regimens. Major causes of treatment failure are insufficient patient compliance and antibiotic resistance. Because of antibiotic resistance, bismuth-based quadruple therapy has also become a first-line regimen in areas with exceedingly high rates of clarithromycin and metronidazole resistance, and is the preferred second-line option otherwise. Triple therapies based on levofloxacin and/or rifabutin mainly with combination of amoxicillin are options if multiple eradication failure occurs. However, following therapy failure beyond a second treatment attempt requires antibiotic resistance testing. New drugs and adjuvant agents have been reported but their efficacy needs further evaluation.

Susceptibility-guided vs. empiric retreatment of Helicobacter pylori infection after treatment failure

Successful eradication of Helicobacter pylori after failure of standard triple therapy is difficult because of the higher resistance to metronidazole and clarithromycin. We evaluated the efficacy of susceptibility-guided vs. empiric retreatment for H. pylori after at least one treatment failure and determined the prevalence of posttreatment antibiotic resistance. Forty-nine patients in whom at least one treatment regimen for H. pylori eradication had failed underwent gastric biopsy and culture and were retreated according to the in vitro susceptibility results. Findings were compared with those for 49 control patients referred to our center for a (13)C-urea breath test. H. pylori eradication was assessed by urea breath test at least 6 weeks after retreatment in both groups. Susceptibility-guided retreatment was associated with better eradication rates than empiric treatment. The difference remained significant in stratified and multivariate analysis. Susceptibility-guided retreatment appears to be significantly more effective than empiric retreatment in eradicating H. pylori after at least one previous treatment failure.

Quinolone resistance in Helicobacter pylori isolates in Germany

We show that quinolone resistance in Helicobacter pylori has reached an alarming level in Germany. Our data suggest that the use of quinolones requires prior antimicrobial susceptibility testing, especially for isolates from patients who have already undergone previous unsuccessful eradication treatments, and also underline the further need for surveillance studies to monitor antibiotic resistance in H. pylori.

Randomized trial of rifabutin-based triple therapy and high-dose dual therapy for rescue treatment of Helicobacter pylori resistant to both metronidazole and clarithromycin

BACKGROUND

The clinical management of Helicobacter pylori infected patients who failed standard eradication therapies remains a challenge.

AIM

To investigate the efficacy of rifabutin-based triple therapy and high-dose dual therapy for rescue treatment of H. pylori, and the correlation between cytochrome P450 2C19 (CYP2C19) polymorphisms and treatment outcome.

METHODS

Patients infected with H. pylori resistant to both metronidazole and clarithromycin (n = 145) were randomized to either esomeprazole 20 mg, rifabutin 150 mg and amoxicillin 1 g, each given b.d. for 7 days (ERA), or to omeprazole 40 mg and amoxicillin 1000 mg, each given t.d.s. for 14 days (OA). Crossover therapy was offered in cases of persistent infection. CYP2C19 polymorphisms were determined by polymerase chain reaction restriction fragment length polymorphism.

RESULTS

Intention-to-treat and per-protocol eradication rates were: ERA 74% (62.4-83.6) and 78% (66.7-87.3); high-dose OA 70% (57.5-79.7) and 75% (62.5-84.5). Crossover therapy was successful in seven of 10 patients with ERA and in eight of 10 patients with OA. Premature discontinuation of treatment occurred in 2% and 5% of patients, respectively. There was only a non-significant trend to lower eradication rates in homozygous extensive metabolizers.

CONCLUSIONS

Triple therapy with esomeprazole, rifabutin and amoxicillin and high-dose omeprazole/amoxicillin are comparable and effective and safe for rescue therapy of H. pylori regardless of the patient's CYP2C19 genotype.

Efficacy of metronidazole as second-line drug for the treatment of Helicobacter pylori Infection in the Japanese population: a multicenter study in the Tokyo Metropolitan Area

BACKGROUND

With the increase in the frequency of clarithromycin-resistant Helicobacter pylori (H. pylori), there is rising concern about the decline of the eradication rate of this infection following treatment. The Tokyo Hp Study Group examined the eradication rate in response to a second-line regimen consisting of proton pump inhibitor (PPI), amoxicillin, and metronidazole by conducting a multicenter study in the Tokyo Metropolitan Area.

MATERIALS AND METHODS

Two hundred and twenty-eight patients with H. pylori infection, in whom the first-line therapy with a PPI, amoxicillin, and clarithromycin administered for 1 week had failed to eradicate the infection, were enrolled in this study. These cases were randomly assigned to one of the two second-line regimens containing metronidazole (PPI/AM500 or PPI/AM750) administered for 1 week. 13C-urea breath test was performed as a diagnostic method test for H. pylori infection not earlier than 8 weeks after the second-line therapy.

RESULTS

Intention-to-treat (ITT) and per-protocol (PP) analyses revealed an eradication rate of 87.6 and 90.6%, respectively, following PPI/AM500 treatment, and 86.9 and 88.6%, respectively, following PPI/AM750 treatment. Neither analysis revealed any significant difference in the eradication rate between PPI/AM500 and PPI/AM750 (p = .876 and .621, respectively). According to ITT and PP analyses, the eradication rates following treatment with PPI/AM500 were 85.2 and 88.5% with the use of lansoprazole, 62.5 and 62.5% with the use of omeprazole, and 93.2 and 96.5% with the use of rabeprazole, respectively. There was a significant difference in the eradication rates between PPI (omeprazole)/AM500 and PPI (rabeprazole)/AM500. In the case of PPI/AM750, the corresponding eradication rates were 84.8 and 87.0% with the use of lansoprazole, 92.9 and 92.9% with the use of omeprazole, and 92.9 and 92.9% with the use of rabeprazole, respectively. There were no significant differences in the eradication rates obtained with the use of the three PPIs.

CONCLUSIONS

Both PPI/AM500 and PPI/AM750 administered for 1 week appeared to be highly effective second-line regimens for the treatment of H. pylori infection in Japanese patients. From the viewpoint of adverse events, PPI/AM500 appeared to be safe compared with PPI/AM750.

Update on Therapeutic Options for Helicobacter pylori-related Diseases

Triple therapy including clarithromycin, amoxicillin, and a proton pump inhibitor (PPI) has been recommended as the treatment of choice for Helicobacter pylori eradication. This regimen is now challenged by an increasing level of clarithromycin resistance that jeopardizes the treatment success. When clarithromycin resistance has been detected, or when its rate is known to be high in the geographic area, this drug cannot be used. It can be replaced by metronidazole, the resistance of which has a limited clinical relevance. Another option is to prescribe tetracycline and metronidazole with a PPI or ranitidine bismuth citrate. New antibiotics such as levofloxacin or rifabutin can also be used in combination with amoxicillin and a PPI. Probiotics can be added to all of these regimens to improve compliance by decreasing adverse events. But some authors advocate a quadruple therapy as a first-line treatment. Solutions to improve the limitations of this last regimen are now being proposed. Clarification of the controversial treatment indications such as gastroesophageal reflux disease or prevention of nonsteroidal anti-inflammatory drug gastroduodenal symptoms has been made. The question of prevention of gastric carcinoma by H. pylori eradication remains unanswered.

Amoxicillin resistance in Helicobacter pylori: studies from Tokyo, Japan from 1985 to 2003

BACKGROUND

Previous reports revealed no resistant strains of amoxicillin (AMPC), which is usually used in eradication therapy for H. pylori infection. However, the frequency and evolution of natural AMPC-resistant strains in the Japanese population remains unknown.

AIM

To assess the prevalence of H. pylori resistance against AMPC in the Tokyo area, a collection of 648 H. pylori strains isolated from patients with GI diseases from 1985 to 2003 was tested for their sensitivity to AMPC.

METHODS

The susceptibility of the strains was assessed by determination of the minimal inhibitory concentration (MIC) using the E-test and/or the Dry-plate method. The susceptibility breakpoints of AMPC for H. pylori were: sensitive (AMPC-S); MIC < 0.04 microg/ml, intermittent resistance (AMPC-I); 0.04-1, resistant (AMPC-R); > 1.

RESULTS

No AMPC-R strains were detected in the strains isolated between 1985 and 1996, while the rate of resistance was determined to be 1.1%, 2.1%, 5.4%, 5.6%, 0%, 8.8%, and 1.5% every year, respectively, from 1997 to 2003. The percentage of AMPC-I strains increased from 2000 to 2003. The total eradication rate of H. pylori in the patients who received triple therapy containing AMPC was 81.4% (214/263). Classified as above, the rates of AMPC-S, AMPC-I, and AMPC-R were 84.6%, 77.8%, 25%, respectively.

CONCLUSION

H. pylori resistance to AMPC is still rare in Japan, although the percentage of AMPC-I strains has increased over the last 4 years. The frequency of isolation of strains showing true resistance to AMPC may increase in the future, along with an increase in the frequency of isolation of AMPC-I strains.

Therapy of Helicobacter pylori

This represents an overview of the main data published over the last year on the therapy of Helicobacter pylori. The problem of increasing failure of H. pylori eradication has been the main focus, with increasing resistance and poor patient compliance being the main culprits. Simple regimens are necessary to improve patient compliance. New antibiotics and novel agents are appraised with mixed results.