A clinical practice viewpoint: to culture or not to culture Helicobacter pylori?

Sequential versus Standard Triple Therapy for First-Line Helicobacter pylori Eradication: An Update

BACKGROUND

non-bismuth sequential therapy (SEQ) was suggested as a first-line anti-Helicobacter pylori treatment alternative to standard triple therapy (STT).

METHODS

We conducted a systematic review with a meta-analysis of randomized controlled trials (RCTs) comparing the efficacy of 10-day SEQ vs. STT (of at least 7 days) using bibliographical searches up to July 2021, including treatment-naïve adult or children. The intention-to-treat (ITT) eradication rate and the risk difference (RD) were calculated.

RESULTS

Overall, 69 RCTs were evaluated, including 19,657 patients (9486 in SEQ; 10,171 in STT). Overall, SEQ was significantly more effective than STT (82% vs. 75%; RD 0.08; p < 0.001). The results were highly heterogeneous (I2 = 68%), and 38 studies did not demonstrate differences between therapies. Subgroup analyses suggested that patients with clarithromycin resistance only and all geographical areas but South America could benefit more from SEQ. Both therapies have evolved over the years, showing similar results when STT lasted 14 days; however, a tendency toward lower SEQ efficacy was noted from 2010 onwards.

CONCLUSIONS

Prior to 2010, SEQ was significantly more effective than STT, notably when 7-day STT was prescribed. A tendency toward lower differences between SEQ and STT has been noted, especially when using 10-day STT. None of the therapies achieved an optimal efficacy and therefore cannot be recommended as a valid first-line H. pylori treatment.

Helicobacter pylori: A Contemporary Perspective on Pathogenesis, Diagnosis and Treatment Strategies

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the gastric mucosa and is associated with various gastrointestinal disorders. H. pylori is a pervasive pathogen, infecting nearly 50% of the world's population, and presents a substantial concern due to its link with gastric cancer, ranking as the third most common cause of global cancer-related mortality. This review article provides an updated and comprehensive overview of the current understanding of H. pylori infection, focusing on its pathogenesis, diagnosis, and treatment strategies. The intricate mechanisms underlying its pathogenesis, including the virulence factors and host interactions, are discussed in detail. The diagnostic methods, ranging from the traditional techniques to the advanced molecular approaches, are explored, highlighting their strengths and limitations. The evolving landscape of treatment strategies, including antibiotic regimens and emerging therapeutic approaches, is thoroughly examined. Through a critical synthesis of the recent research findings, this article offers valuable insights into the contemporary knowledge of Helicobacter pylori infection, guiding both clinicians and researchers toward effective management and future directions in combating this global health challenge.

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.

Genotypic detection of metronidazole and clarithromycin resistance in dyspeptic patients with helicobacter pylori

In Egypt, antibiotic sensitivity analysis for Helicobacter pylori is not routinely performed. We aimed to identify the clarithromycin and metronidazole resistance directly from gastric biopsies for better guide treatment regimens. This cross-sectional descriptive study included 75 adult dyspeptic patients referred to the upper endoscopy unit in Suez Canal University Hospital, Ismailia, Egypt. Gastric biopsies were taken for rapid urease test (RUT) and cultured on brucella agar with antibiotic supplements. Genomic DNA was extracted directly from the specimen, and PCR was performed for direct detection of H. pylori. Also, to explore clarithromycin and metronidazole resistance, mutations in the 23S rRNA gene and the rdxA gene were investigated. We found that 60 samples were positive to RUT (80%), and only 4 samples were positive by culture. UreC gene was detected in 45 specimens. Meanwhile, 26 isolates were contained mutations at positions 2142 and 2143. Amplification of the metronidazole rdx gene was performed by conventional PCR. Out of 45 isolates, DNA sequence analysis of PCR product showed the wild type (ACA) in 9 isolates, while the mutant type (ATA) was detected in 28 isolates. We found a significant proportion of clarithromycin and metronidazole resistance among H. pylori infected patients in our region.

Future challenges in gastroenterology and hepatology, between innovations and unmet needs: A SIGE Young Editorial Board's perspective

Gastroenterology, Digestive Endoscopy and Hepatology have faced significant improvements in terms of diagnosis and therapy in the last decades. However, many fields still remain poorly explored, and many questions unanswered. Moreover, basic-science, as well as translational and clinical discoveries, together with technology advancement will determine further steps toward a better, refined care for many gastroenterological disorders in the future. Therefore, the Young Investigators of the Italian Society of Gastroenterology (SIGE) joined together, offering a perspective on major future innovations in some hot clinical topics in Gastroenterology, Endoscopy, and Hepatology, as well as the current pitfalls and the grey zones.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifier is NCT05002595.

Helicobacter pylori eradication following first-line treatment failure in Europe: What, how and when chose among different standard regimens? A systematic review

Cure rate following standard first-line regimens for Helicobacter pylori eradication is decreasing so several patients require two or more treatments. Antibiotic susceptibility-based therapy, advised in current guidelines, is largely impracticable in clinical practice. Some 'standard' regimens (triple therapies based on either levofloxacin or rifabutin, bismuth-based quadruple therapies, sequential, concomitant and hybrid therapies) were empirically used as rescue therapies. We performed a systematic review on recent studies carried out in European countries dealing with these regimens. A total of 24 studies, with 3804 patients, were identified. As second-line therapy, Pylera (89.2%) and sequential therapy (92.5%) achieved significantly higher cure rates as compared to all the other regimens. As third-line therapy, levofloxacin-based therapy (84.1%) and Pylera (83.6%) achieved similarly high cure rates, whereas standard, bismuth-based quadruple therapy (64.1%) achieved the lowest. As a rescue therapy, the success rate was close to 75% following all therapies used, with data on rifabutin-based regimen consolidated in the larger sample size. Overall, levofloxacin-amoxicillin triple therapy achieved higher eradication rates when the 14- rather than 10-day regimen was used (87.1 vs. 72.2%; P = 0.003). Among bismuth-based therapies, Pylera achieved a significantly higher eradication rate than standard quadruple therapy (88 vs. 67%; P < 0.0001). These data suggest that a wise 'therapeutic package' following first-line therapy could be Pylera, levofloxacin- and rifabutin-based therapy, as long as Pylera therapy was not used as a first-line regimen and levofloxacin-based regimen was administered for 14 days.

Rescue Therapies for H. pylori Infection in Italy

Background/Aims: Curing Helicobacter pylori infection remains challenging for clinicians, as no proposed first-line therapy achieves bacterial eradication in all treated patients so that several patients need two or more consecutive treatments. Bacterial culture with antibiotics susceptibility testing is largely unachievable in Italy, and empiric second-line and rescue therapies are generally used. This study aimed to identify what eradication regimens perform better in Italy, following first-line therapy failure. Methods: We performed a literature search on PubMed for studies on standard therapy regimens used as second-line or rescue treatments performed in adult patients. Studies including modified drug combinations were not considered. Both intention-to-treat and per- protocol analyses were computed for each therapy subgroup. Results: Data from 35 studies with a total of 4830 patients were eventually considered. As a second-line therapy, Pylera® (90.6%) and a sequential regimen (89.8%) achieved eradication rates significantly higher than other therapies. For third-line therapy, a levofloxacin-based regimen and Pylera® achieved comparable eradication rates (88.2% vs. 84.7%; p = 0.2). Among therapies used as fourth (or more) attempts, Pylera® and a rifabutin-based therapy achieved 77.4% and 66.4% cure rates, respectively (p = 0.013). A therapy sequence based on the type of first-line therapy used was proposed. Conclusions: Data obtained through our review indicate that standard therapies for H. pylori eradication can be used when following an appropriate sequence, allowing clinicians to improve the cure rate without resorting to bacterial culture.

Next Generation Sequencing for the Prediction of the Antibiotic Resistance in Helicobacter pylori: A Literature Review

Background and aims: Only a few antimicrobials are effective against H. pylori, and antibiotic resistance is an increasing problem for eradication therapies. In 2017, the World Health Organization categorized clarithromycin resistant H. pylori as a "high-priority" bacterium. Standard antimicrobial susceptibility testing can be used to prescribe appropriate therapies but is currently recommended only after the second therapeutic failure. H. pylori is, in fact, a "fastidious" microorganism; culture methods are time-consuming and technically challenging. The advent of molecular biology techniques has enabled the identification of molecular mechanisms underlying the observed phenotypic resistance to antibiotics in H. pylori. The aim of this literature review is to summarize the results of original articles published in the last ten years, regarding the use of Next Generation Sequencing, in particular of the whole genome, to predict the antibiotic resistance in H. pylori.Methods: a literature research was made on PubMed. The research was focused on II and III generation sequencing of the whole H. pylori genome. Results: Next Generation Sequencing enabled the detection of novel, rare and complex resistance mechanisms. The prediction of resistance to clarithromycin, levofloxacin and amoxicillin is accurate; for other antimicrobials, such as metronidazole, rifabutin and tetracycline, potential genetic determinants of the resistant status need further investigation.

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.

Helicobacter pylori Primary and Secondary Genotypic Resistance to Clarithromycin and Levofloxacin Detection in Stools: A 4-Year Scenario in Southern Italy

Antibiotic resistance has become an emerging problem for treating Helicobacter pylori (H. pylori) infection. Clarithromycin and levofloxacin are two key antibiotics used for its eradication. Therefore, we reviewed our experience with genotypic resistance analysis in stools to both clarithromycin and levofloxacin in the last four years to evaluate time trends, both in naive and failure patients. Patients collected a fecal sample using the THD fecal test device. Real-time polymerase chain reaction was performed to detect point mutations conferring resistance to clarithromycin (A2142C, A2142G, and A2143G in 23S rRNA) and levofloxacin (substitutions at amino acid position 87 and 91 of gyrA). One hundred and thirty-five naive patients were recruited between 2017-2020. Clarithromycin resistance was detected in 37 (27.4%). The time trend did not show any significant variation from 2017 to 2020 (p = 0.33). Primary levofloxacin resistance was found in 26 subjects (19.2%), and we observed a dramatic increase in rates from 2017 (10%) to 2018 (3.3%), 2019 (20%), and 2020 (37.8%). Ninety-one patients with at least one eradication failure were recruited. Secondary resistance to clarithromycin and levofloxacin was found in 59 (64.8%) and 45 patients (59.3%), respectively. In conclusion, our geographic area has a high risk of resistance to clarithromycin. There is also a progressive spreading of levofloxacin-resistant strains.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Systematic review: Would susceptibility-guided treatment achieve acceptable cure rates for second-line Helicobacter pylori therapy as currently practiced?

BACKGROUND

Susceptibility-guided treatment has been proposed as a way to improve Helicobacter pylori eradication rates. Evidence on its efficacy for rescue therapy is very scarce. The aim of this study was to indirectly assess the applicability and effectiveness of susceptibility-guided treatment by evaluating (a) the rate of acceptance of endoscopy, (b) its success in detecting resistances, and (c) infection cure rates in patients harboring strains found to be susceptible to the antibiotics administered in clinical trials in which the efficacy of second-line treatments was reported.

METHODS

A systematic review of studies evaluating second-line H pylori treatment was carried out in multiple databases. Studies reporting antibiotic susceptibility evaluation and/or cure rates in patients harboring sensitive and resistant strains were selected. Data were extracted in duplicate.

RESULTS

The systematic review identified 36 eligible studies. Acceptance was evaluated in only one study of 60 patients, of whom only 38 agreed to endoscopy. Among the 2890 patients who received endoscopy and culture, resistances were finally determined in 86.5%. Cure rate was 72.5% in the 113 patients harboring a clarithromycin-susceptible strain after previous clarithromycin treatment, 93.5% in the 765 patients harboring a metronidazole-susceptible strain, and 83.8% in the 192 patients harboring a levofloxacin-susceptible strain. No studies with repeated administration of levofloxacin or metronidazole were found.

CONCLUSION

Even if the culture shows a clarithromycin-sensitive strain, repeating clarithromycin after a first failure should be discouraged. Susceptibility-guided treatment alone did not achieve adequate cure rates for rescue therapies. Additional measures are needed to design rescue treatments that consistently achieve excellent cure rates.

Cost-effectiveness of a tailored Helicobacter pylori eradication strategy based on the presence of a 23S ribosomal RNA point mutation that causes clarithromycin resistance in Korean patients

BACKGROUND AND AIM

The Helicobacter pylori eradication rate using conventional triple therapy has decreased due to clarithromycin (CAM) resistance in H. pylori. Recently, dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) can be used to detect H. pylori and point mutations in the 23S ribosomal RNA gene causing CAM resistance. This study aimed to evaluate the success rate and cost-effectiveness of tailored H. pylori eradication using DPO-PCR.

METHODS

The H. pylori-positive patients diagnosed by a rapid urease test or DPO-PCR were enrolled from a single academic hospital. The patients with positive rapid urease test results received a CAM-based triple regimen. In the tailored therapy group that underwent DPO-PCR testing, patients with A2142G and/or A2143G point mutations were treated with a bismuth-containing quadruple regimen. The cost-effectiveness of H. pylori eradication success was evaluated according to the average cost per patient and the incremental cost-effectiveness ratio.

RESULTS

A total of 243 patients were allocated to the triple therapy group and 124 patients to the tailored therapy group. The first-line eradication rate of H. pylori was significantly higher in the tailored therapy group than in the conventional triple therapy group (92.7% vs 76.5%, P < 0.001). The average costs per patient for tailored therapy were $307.37 and $299.59 for first-line and second-line treatments, respectively. Compared with triple therapy, the incremental cost-effectiveness ratios of tailored therapy were $3.96 and -$3.81 per patient for first-line and second-line treatments, respectively.

CONCLUSION

In Korea, tailored H. pylori eradication using DPO-PCR may be more cost-effective than conventional triple therapy.

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.

Helicobacter pylori DNA isolation in the stool: an essential pre-requisite for bacterial noninvasive molecular analysis

PURPOSE

Real-time polymerase chain reaction (RT-PCR) is a widely used technique for bacterial and viral infection diagnosis. Herein, we report our preliminary experience in retrieving H. pylori genetic sequences in stools and analyzing genotypic clarithromycin resistance by RT-PCR (noninvasive), with the aim of comparing this procedure with that performed on biopsy samples (invasive).

MATERIALS AND METHODS

After 'in vitro' demonstration of H. pylori DNA detection from pure and stool-mixed bacteria, 52 consecutive patients at the first diagnosis of infection were investigated. DNA was extracted from biopsy tissue and stool samples (THD^® Fecal Test, Italy). RT-PCR was performed to detect 23S rRNA encoding bacterial subunit gene and search A2143G, A2142C, A2142G point mutations for clarithromycin resistance assessment.

RESULTS

RT-PCR showed H. pylori positive DNA in all infected patients with full concordance between tissue and stool detection (100%). We found A2143G mutation in 10 (19.2%), A2142G in 4 (7.7%) and A2142C in 5 (9.6%) patients; there was a full agreement between biopsy and fecal samples. A2143G was found in all the four A2142G positive cases and in three out of the five A2142C positive strains. Overall clarithromycin resistance rate in our series was 23%.

CONCLUSIONS

Despite the need of confirmation on large sample, stool RT-PCR analysis could represent a feasible tool to detect H. pylori DNA sequences and antibiotic resistance point mutations. As compared to tissue molecular analysis, this technique is noninvasive, with potential advantages such as improvement of patient compliance, reduction of diagnostic procedure time/cost and improvement of therapeutic outcome.

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.

Sequential versus standard triple first-line therapy for Helicobacter pylori eradication

BACKGROUND

Non-bismuth quadruple sequential therapy (SEQ) comprising a first induction phase with a dual regimen of amoxicillin and a proton pump inhibitor (PPI) for five days followed by a triple regimen phase with a PPI, clarithromycin and metronidazole for another five days, has been suggested as a new first-line treatment option to replace the standard triple therapy (STT) comprising a proton pump inhibitor (PPI), clarithromycin and amoxicillin, in which eradication proportions have declined to disappointing levels.

OBJECTIVES

To conduct a meta-analysis of randomised controlled trials (RCTs) comparing the efficacy of a SEQ regimen with STT for the eradication of H. pylori infection, and to compare the incidence of adverse effects associated with both STT and SEQ H. pylori eradication therapies.

SEARCH METHODS

We conducted bibliographical searches in electronic databases, and handsearched abstracts from Congresses up to April 2015.

SELECTION CRITERIA

We sought randomised controlled trials (RCTs) comparing 10-day SEQ and STT (of at least seven days) for the eradication of H. pylori. Participants were adults and children diagnosed as positive for H. pylori infection and naïve to H. pylori treatment.

DATA COLLECTION AND ANALYSIS

We used a pre-piloted, tabular summary to collect demographic and medical information of included study participants as well as therapeutic data and information related to the diagnosis and confirmatory tests.We evaluated the difference in intention-to-treat eradication between SEQ and STT regimens across studies, and assessed sources of the heterogeneity of this risk difference (RD) using subgroup analyses.We evaluated the quality of the evidence following Cochrane standards, and summarised it using GRADE methodology.

MAIN RESULTS

We included 44 RCTs with a total of 12,284 participants (6042 in SEQ and 6242 in STT). The overall analysis showed that SEQ was significantly more effective than STT (82% vs 75% in the intention-to-treat analysis; RD 0.09, 95% confidence interval (CI) 0.06 to 0.11; P < 0.001, moderate-quality evidence). Results were highly heterogeneous (I² = 75%), and 20 studies did not demonstrate differences between therapies.Reporting by geographic region (RD 0.09, 95% CI 0.06 to 0.12; studies = 44; I² = 75%, based on low-quality evidence) showed that differences between SEQ and STT were greater in Europe (RD 0.16, 95% CI 0.14 to 0.19) when compared to Asia, Africa or South America. European studies also showed a tendency towards better efficacy with SEQ; however, this tendency was reversed in 33% of the Asian studies. Africa reported the closest risk difference (RD 0.14 , 95% 0.07 to 0.22) to Europe among studied regions, but confidence intervals were wider and therefore the quality of the evidence showing SEQ to be superior to STT was reduced for this region.Based on high-quality evidence, subgroup analyses showed that SEQ and STT therapies were equivalent when STT lasted for 14 days. Although, overall, the mean eradication proportion with SEQ was over 80%, we noted a tendency towards a lower average effect with this regimen in the more recent studies (2008 and after); weighted linear regression showed that the efficacies of both regimens evolved differently over the years, having a higher reduction in the efficacy of SEQ (-1.72% yearly) than in STT (-0.9% yearly). In these more recent studies (2008 and after) we were also unable to detect the superiority of SEQ over STT when STT was given for 10 days.Based on very low-quality evidence, subgroup analyses on antibiotic resistance showed that the widest difference in efficacy between SEQ and STT was in the subgroup analysis based on clarithromycin-resistant participants, in which SEQ reached a 75% average efficacy versus 43% with STT.Reporting on adverse events (AEs) (RD 0.00, 95% CI -0.02 to 0.02; participants = 8103; studies = 27; I² = 26%, based on high-quality evidence) showed no significant differences between SEQ and STT (20.4% vs 19.5%, respectively) and results were homogeneous.The quality of the studies was limited due to a lack of systematic reporting of the factors affecting risk of bias. Although randomisation was reported, its methodology (e.g. algorithms, number of blocks) was not specified in several studies. Additionally, the other 'Risk of bias' domains (such as allocation concealment of the sequence randomisation, or blinding during either performance or outcome assessment) were also unreported.However, subgroup analyses as well as sensitivity analyses or funnel plots indicated that treatment outcomes were not influenced by the quality of the included studies. On the other hand, we rated 'length of STT' and AEs for the main outcome as high-quality according to GRADE classification; but we downgraded 'publication date' quality to moderate, and 'geographic region' and 'antibiotic resistance' to low- and very low-quality, respectively.

AUTHORS' CONCLUSIONS

Our meta-analysis indicates that prior to 2008 SEQ was more effective than STT, especially when STT was given for only seven days. Nevertheless, the apparent advantage of sequential treatment has decreased over time, and more recent studies do not show SEQ to have a higher efficacy versus STT when STT is given for 10 days.Based on the results of this meta-analysis, although SEQ offers an advantage when compared with STT, it cannot be presented as a valid alternative, given that neither SEQ nor STT regimens achieved optimal efficacy ( ≥ 90% eradication rate).

Review article: the global emergence of Helicobacter pylori antibiotic resistance

BACKGROUND

Helicobacter pylori is one of the most prevalent global pathogens and can lead to gastrointestinal disease including peptic ulcers, gastric marginal zone lymphoma and gastric carcinoma.

AIM

To review recent trends in H. pylori antibiotic resistance rates, and to discuss diagnostics and treatment paradigms.

METHODS

A PubMed literature search using the following keywords: Helicobacter pylori, antibiotic resistance, clarithromycin, levofloxacin, metronidazole, prevalence, susceptibility testing.

RESULTS

The prevalence of bacterial antibiotic resistance is regionally variable and appears to be markedly increasing with time in many countries. Concordantly, the antimicrobial eradication rate of H. pylori has been declining globally. In particular, clarithromycin resistance has been rapidly increasing in many countries over the past decade, with rates as high as approximately 30% in Japan and Italy, 50% in China and 40% in Turkey; whereas resistance rates are much lower in Sweden and Taiwan, at approximately 15%; there are limited data in the USA. Other antibiotics show similar trends, although less pronounced.

CONCLUSIONS

Since the choice of empiric therapies should be predicated on accurate information regarding antibiotic resistance rates, there is a critical need for determination of current rates at a local scale, and perhaps in individual patients. Such information would not only guide selection of appropriate empiric antibiotic therapy but also inform the development of better methods to identify H. pylori antibiotic resistance at diagnosis. Patient-specific tailoring of effective antibiotic treatment strategies may lead to reduced treatment failures and less antibiotic resistance.

Loop-Mediated Isothermal Amplification as a Fast Noninvasive Method of Helicobacter pylori Diagnosis

BACKGROUND

Helicobacter pylori infection is etiologically associated with some important health problems such as gastric cancer. Because of the high clinical importance of H. pylori infection, development of a noninvasive test for the detection of H. pylori is desirable.

METHODS

In this study, a loop-mediated isothermal amplification (LAMP) targeted ureC of H. pylori was evaluated on 100 stool specimens and compared with a stool antigen test. Culture and rapid urease test were considered as gold standards.

RESULTS

The overall detection rate of the fecal antigen test and LAMP was 58% and 82%, respectively. The analytical sensitivity of the fecal antigen test and LAMP was 500 and 10 H. pylori cells/g and 10 fg DNA/reaction, which is equal to six H. pylori genome.

CONCLUSION

LAMP technique has been characterized by high sensitivity and low detection limit for the detection of H. pylori in stool specimen. Clinical diagnostic performance of LAMP was better than the stool antigen test.

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.

Efficacy of hybrid therapy as first-line regimen for Helicobacter pylori infection compared with sequential therapy

BACKGROUND AND AIM

Recent prospective studies have shown that the sequential therapy has not achieved the target Helicobacter pylori eradication rate of > 80% in Korea. The aim of this study was to therefore assess the efficacy of the hybrid therapy as a first-line treatment for H. pylori eradication in a prospective trial.

METHODS

From December 2012 to August 2013, 184 patients with confirmed H. pylori infections received either the 14-day hybrid therapy or the 14-day sequential therapy. Eradication outcomes were evaluated using a 13C-urea breath test at least 4 weeks after treatment cessation.

RESULTS

A total of 184 patients (90 receiving hybrid treatment and 94 receiving sequential treatment) completed the study. The eradication rates of the hybrid and sequential therapy groups were 81.1% (73/90; 95% confidence interval [CI] = 73.0-89.2%) and 79.8% (75/94; 95%CI = 71.7-87.9%), respectively, by intention-to-treat analysis (P = 0.821). By per protocol analysis, eradication rates were 85.9% (73/85; 95%CI = 78.5-93.3%) and 82.0% (73/89; 95%CI = 74.0-89.9%; P = 0.489), respectively. There were no significant intergroup differences in treatment compliance or discontinuation induced by severe side effects.

CONCLUSIONS

The hybrid therapy achieved acceptable eradication rate (85.9%), but not statistically significantly higher rates than the sequential therapy (82.0%). Further studies are therefore needed to identify first-line treatments with even better eradication rates in the Korean population.

Third-line rescue therapy with bismuth-containing quadruple regimen after failure of two treatments (with clarithromycin and levofloxacin) for H. pylori infection

BACKGROUND

Helicobacter pylori eradication therapy with a proton pump inhibitor (PPI), clarithromycin, and amoxicillin fails in >20 % of cases. A rescue therapy with PPI-amoxicillin-levofloxacin still fails in >20 % of patients.

AIM

To evaluate the efficacy and tolerability of a bismuth-containing quadruple regimen in patients with two consecutive eradication failures.

METHODS

Prospective multicenter study of patients in whom 1st treatment with PPI-clarithromycin-amoxicillin and 2nd with PPI-amoxicillin-levofloxacin had failed. A 3rd eradication regimen with a 7- to 14-day PPI (standard dose b.i.d.), bismuth subcitrate (120 mg q.i.d. or 240 mg b.i.d.), tetracycline (from 250 mg t.i.d. to 500 mg q.i.d.) and metronidazole (from 250 mg t.i.d. to 500 mg q.i.d.). Eradication was confirmed by (13)C-urea-breath-test 4-8 weeks after therapy. Compliance was determined through questioning and recovery of empty medication envelopes. Adverse effects were evaluated by means of a questionnaire.

RESULTS

Two hundred patients (mean age 50 years, 55 % females, 20 % peptic ulcer/80 % uninvestigated-functional dyspepsia) were initially included, and two were lost to follow-up. In all, 97 % of patients complied with the protocol. Per-protocol and intention-to-treat eradication rates were 67 % (95 % CI 60-74 %) and 65 % (58-72 %). Adverse effects were reported in 22 % of patients, the most common being nausea (12 %), abdominal pain (11 %), metallic taste (8.5 %), and diarrhea (8 %), none of them severe.

CONCLUSION

A bismuth-containing quadruple regimen is an acceptable third-line strategy and a safe alternative after two previous H. pylori eradication failures with standard clarithromycin- and levofloxacin-containing triple therapies.

Change of point mutations in Helicobacter pylori rRNA associated with clarithromycin resistance in Italy

Primary clarithromycin resistance is the main factor affecting the efficacy of Helicobacter pylori therapy. This study aimed: (i) to assess the concordance between phenotypic (culture) and genotypic (real-time PCR) tests in resistant strains; (ii) to search, in the case of disagreement between the methods, for point mutations other than those reported as the most frequent in Europe; and (iii) to compare the MICs associated with the single point mutations. In order to perform real-time PCR, we retrieved biopsies from patients in whom H. pylori infection was successful diagnosed by bacterial culture and clarithromycin resistance was assessed using the Etest. Only patients who had never been previously treated, and with H. pylori strains that were either resistant exclusively to clarithromycin or without any resistance, were included. Biopsies from 82 infected patients were analysed, including 42 strains that were clarithromycin resistant and 40 that were clarithromycin susceptible on culture. On genotypic analysis, at least one of the three most frequently reported point mutations (A2142C, A2142G and A2143G) was detected in only 23 cases (54.8%), with a concordance between the two methods of 0.67. Novel point mutations (A2115G, G2141A and A2144T) were detected in a further 14 out of 19 discordant cases, increasing the resistance detection rate of PCR to 88% (P<0.001; odds ratio 6.1, 95% confidence interval 2-18.6) and the concordance to 0.81. No significant differences in MIC values among different point mutations were observed. This study suggests that: (i) the prevalence of the usually reported point mutations may be decreasing, with a concomitant emergence of new mutations; (ii) PCR-based methods should search for at least six point mutations to achieve good accuracy in detecting clarithromycin resistance; and (iii) none of the tested point mutations is associated with significantly higher MIC values than the others.

Primary clarithromycin resistance to Helicobacter pylori: Is this the main reason for triple therapy failure?

Conventional triple therapies for Helicobacter pylori (H. pylori) eradication have recently shown a disappointing reduction in effectiveness in many countries. The main reason for failure was found to be bacterial resistance to one of the most commonly used antibiotics, clarithromycin. An additional problem for conventional triple therapy is the high rate of resistance to metronidazole found in Europe, America and Asia. In Italy, in the last 15 years a 2-fold increase in resistance has occurred. A recent study of the whole of Italy included about 20 patients from each region at the first endoscopic diagnosis of H. pylori infection. The most surprising result was the patchy distribution of resistance, which was almost absent in two regions (one northern and one southern), although the highest prevalence was found in some regions of the South. In the paediatric population we found a 25% prevalence of resistance in a sample of H. pylori positive children observed between 2002 and 2007, mirroring data obtained in southern European countries. Clarithromycin resistance assessment is currently based on phenotypic detection performed after culture the agar dilution method or E-test, and genotypic methods based on polymerase chain reaction (PCR). In a recent comparative study we found a 71.2% agreement between the two methods. Culture-free techniques are highly accurate in finding even minimal traces of genotypically resistant strains. Moreover, PCR-based tools are accurate in detecting a heteroresistant status, defined as the co-existence of some strains that are susceptible and some resistant to the same antibiotic in an individual patient. Three point mutations, namely A2143G, A2142G and A2142C, are responsible for 90% of cases of primary clarithromycin resistance in H. pylori strains isolated in Western countries, although we previously demonstrated that the presence of the A2143G mutation, but not A2142G or A2142C, significantly lowered the H. pylori eradication rate. Treatment failure has considerable cost/benefit implications because of “waste” of National Health System and patient resources, in terms of drugs, further diagnostic tests and medical examination expenses. Therefore, in future it would be very useful to be able to test for clarithromycin resistance before starting conventional triple therapy. Hopefully, fast, effective non-invasive tests may soon be devised to determine this condition.

Fourth-line rescue therapy with rifabutin in patients with three Helicobacter pylori eradication failures

BACKGROUND

In some cases, Helicobacter pylori infection persists even after three eradication treatments.

AIM

To evaluate the efficacy of an empirical fourth-line rescue regimen with rifabutin in patients with three eradication failures.

DESIGN

Multicentre, prospective study.

PATIENTS

In whom the following three treatments had consecutively failed: first (PPI + clarithromycin + amoxicillin); second (PPI + bismuth + tetracycline + metronidazole); third (PPI + amoxicillin + levofloxacin).

INTERVENTION

A fourth regimen with rifabutin (150 mg b.d.), amoxicillin (1 g b.d.) and a PPI (standard dose b.d.) was prescribed for 10 days.

OUTCOME

Eradication was confirmed by (13) C-urea breath test 4-8 weeks after therapy. Compliance and tolerance: Compliance was determined through questioning and recovery of empty medication envelopes. Adverse effects were evaluated using a questionnaire.

RESULTS

One-hundred patients (mean age 50 years, 39% men, 31% peptic ulcer/69% functional dyspepsia) were included. Eight patients did not take the medication correctly (in six cases due to adverse effects). Per-protocol and intention-to-treat eradication rates were 52% (95% CI = 41-63%) and 50% (40-60%). Adverse effects were reported in 30 (30%) patients: nausea/vomiting (13 patients), asthenia/anorexia (8), abdominal pain (7), diarrhoea (5), fever (4), metallic taste (4), myalgia (4), hypertransaminasemia (2), leucopenia (<1,500 neutrophils) (2), thrombopenia (<150,000 platelets) (2), headache (1) and aphthous stomatitis (1). Myelotoxicity resolved spontaneously in all cases.

CONCLUSIONS

Even after three previous H. pylori eradication failures, an empirical fourth-line rescue treatment with rifabutin may be effective in approximately 50% of the cases. Therefore, rifabutin-based rescue therapy constitutes a valid strategy after multiple previous eradication failures with key antibiotics, such as clarithromycin, metronidazole, tetracycline and levofloxacin.

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.

Review article: the effectiveness of standard triple therapy for Helicobacter pylori has not changed over the last decade, but it is not good enough

BACKGROUND  A decrease in the Helicobacter pylori eradication rate after standard triple therapy has been suggested in recent years. AIM  To assess the efficacy of standard triple therapy in the eradication of H. pylori through an epidemiological analysis of all published Spanish trials. A secondary aim was to review the prevalence of clarithromycin resistance in Spain. METHODS  Articles on H. pylori eradication in Spain published in peer-reviewed journals were identified through MEDLINE searches. Studies that included a triple therapy consisting of any proton pump inhibitor with clarithromycin (500 mg b.d.) and amoxicillin (1 g b.d.) for up to 14 days were selected. Spanish studies evaluating the prevalence of clarithromycin resistance were also reviewed. Meta-analysis was performed using the generic inverse variance method. RESULTS The pooled eradication rates by year from Spanish studies evaluating the efficacy of the standard triple regimen revealed a relatively constant rate over the years. Overall, the analysis of the 32 studies (4727 patients) showed a mean H. pylori cure rate of 80% (95% CI = 77-82%) by intention-to-treat and 83% (81-86%) by per-protocol. When only peptic ulcer disease or 7-day regimens were considered, results were similar. Based on 13 studies (3293 patients), mean clarithromycin resistance rate was 8% (5-10%). CONCLUSION Although a decrease in the H. pylori eradication rate after triple therapy has been suggested in recent years, cure rates with this regimen did not change in Spain between 1997 and 2008. However, this by no means indicates that the efficacy of standard triple therapy in Spain is acceptable, as it has been calculated to be around only 80%. Therefore, it is evident that new strategies to improve first-line treatment are urgently needed.

Dual therapy trial using esomeprazole and amoxicillin as third-line rescue therapy for Helicobacter pylori infection

BACKGROUND/AIMS

The purpose of this study was to evaluate the efficacy and tolerability of dual therapy consisting of esomeprazole and amoxicillin as a rescue therapy for Helicobacter pylori infection.

METHODS

From December 2009 to August 2010, 21 patients who experienced two consecutive eradication failures were included. They received esomeprazole (40 mg, b.i.d.) and amoxicillin (1,000 mg, b.i.d.) for 14 days as a third eradication regimen. Compliance and side effects were determined from an interview. H. pylori status was evaluated using the (13)C urea breath test at least 6 weeks after treatment.

RESULTS

The mean age of the patients was 59 years and included 52% males. Indications for treatment were functional dyspepsia (61.9%), peptic ulcer disease (28.6%), and gastric adenoma (9.5%). H. pylori was eradicated in 14 of 21 (66.7%) patients. Minor side effects were reported in three of the 21 patients (14.3%). These side effects consisted mainly of nausea and epigastric discomfort.

CONCLUSIONS

A 2-week course of dual therapy failed to show satisfactory results in third-line H. pylori eradication, but it was very safe and tolerable. Therefore, dual therapy constitutes an encouraging empirical strategy for the elderly and infirm patients with multiple previous eradication failures.

Management of Helicobacter pylori infection

Helicobacter pylori is the cause of peptic ulcer, gastric cancer and gastric lymphoma. Diagnosis of H. pylori infection can be made using invasive and noninvasive tests. Invasive tests based on endoscopy, such as histology, are recommended when a gastric malignancy is suspected. Alternatively, noninvasive tests, such as the urea breath test and stool tests are useful for H. pylori diagnosis and follow-up. Triple therapy with either amoxicillin or metronidazole, clarithromycin and proton pump inhibitor given twice daily for 7-14 days is the recommended first-line treatment, after having checked the individual clarithromycin antimicrobial susceptibility. A triple therapy with levofloxacin, amoxicillin and proton pump inhibitor for 10-14 days should be used as second-line treatment, where the strains are susceptible to fluoroquinolone. Alternatively, bismuth-based quadruple therapy is recommended.

Efficacy of H. pylori eradication with a sequential regimen followed by rescue therapy in clinical practice

BACKGROUND

Current Italian guidelines suggest sequential therapy as first-line therapy and a levofloxacin-based rescue therapy for Helicobacter pylori eradication. We evaluated the efficacy of these therapies in clinical practice.

METHODS

84 consecutive patients with dyspeptic symptoms and proven H. pylori infection by either UBT or upper endoscopy with biopsies were enrolled. Patients received a 10-day sequential therapy with lansoprazole 30mg plus amoxycillin 1g (all twice daily) for the first 5 days, followed by lansoprazole 30mg, clarithromycin 500mg, and metronidazole 500mg (all twice daily) for the remaining 5 days. Eradication failure patients received triple therapy with lansoprazole 30mg, levofloxacin 250mg, and amoxycillin 1g (all twice daily) for 10 days.

RESULTS

Following the sequential therapy H. pylori eradication was achieved in 70/84 (83.3%; 95% CI=75.4-91.3) patients, and in 70/77 (90.9%; 95% CI=84.5-97.3) patients at ITT and PP analyses, respectively. The infection was cured in all 7 eradication failure patients by using second-line therapy.

CONCLUSIONS

A sequential regimen as first-line therapy and a 10-day levofloxacin-based triple regimen in those patients who failed to clear the infection, appear to be a valid therapeutic strategy for management of H. pylori infection in clinical practice.

Helicobacter pylori antibiotic resistance and [13C]urea breath test values

A correlation between delta over baseline (DOB) values of the [(13)C]urea breath test (UBT) and Helicobacter pylori clarithromycin resistance has been reported, suggesting a possible predictive role of UBT in therapeutic outcome. However, available data are limited and conflicting. This study aimed to clarify this issue, assessing the possible relationship between H. pylori resistance towards different antibiotics (clarithromycin, metronidazole and levofloxacin) and UBT values. The data showed similar DOB values between susceptible and resistant strains for clarithromycin (46.9+/-32.3 vs 45.7+/-30.6; P=0.8), metronidazole (46.4+/-29.6 vs 47.4+/-37.9; P=0.8), and levofloxacin (45.0+/-30.2 vs 54.2+/-38.4; P=0.08). Likewise, comparable DOB values were observed between susceptible and multidrug-resistant strains (45.4+/-29.6 vs 54.8+/-44.8; P=0.1). In conclusion, our data failed to find a significant correlation between UBT values and H. pylori antibiotic resistance.

A novel compound from celery seed with a bactericidal effect against Helicobacter pylori

Objectives

The aim was to purify and characterise an antimicrobial component from celery (Apium graveolens) seeds, which have been used for centuries as a herbal medicine with reported antibacterial effects.

Methods

A crude alcoholic extract of celery seeds was fractionated by organic solvent extractions, column chromatography and HPLC. Fractions were assayed for antimicrobial activity against the gastric pathogen Helicobacter pylori and other bacteria. The purified antibacterial component was characterised via MS and NMR. Preliminary investigation of its mechanism of action included morphological studies, incorporation of macromolecular precursors, membrane integrity and two-dimensional protein electrophoresis.

Key findings

The purified component, termed ‘compound with anti-Helicobacter activity’ (CAH), had potent bactericidal effects against H. pylori; the minimum inhibitory concentration and minimum bactericidal concentration were 3.15 μg/ml and 6.25–12.5 μg/ml, respectively. CAH (Mr = 384.23; empirical formula C24H32O4) had specific inhibitory effects on H. pylori and was not active against Campylobacter jejuni or Escherichia coli. MS and NMR data were consistent with a dimeric phthalide structure. The results appeared to rule out mechanisms that operated solely by loss of membrane integrity or inhibition of protein or nucleic acid synthesis.

Conclusions

CAH may be suitable for further investigation as a potent agent for treating H. pylori infections.

Phenotypic and genotypic Helicobacter pylori clarithromycin resistance and therapeutic outcome: benefits and limits

INTRODUCTION

Primary clarithromycin resistance is increasing worldwide, and it has been regarded as the main factor reducing the efficacy of Helicobacter pylori therapy. However, the clinical consequence of either phenotypic or genotypic resistance still remains unclear. This study aimed to evaluate: (i) the concordance between phenotypic (culture) and genotypic (real-time PCR) tests in assessing primary clarithromycin resistance; and (ii) the role of both in therapeutic outcome.

METHODS

A post hoc subgroup study was selected from a double-blind, placebo-controlled trial, enrolling 146 patients with dyspepsia or peptic ulcers never previously treated. Real-time PCR and Etest on bacterial culture for assessing clarithromycin resistance were performed. [(13)C]urea breath test (UBT), histology and rapid urease tests at entry and UBT after 4-8 weeks were used to assess infection and eradication. All patients received a 10 day therapy.

RESULTS

Prevalence of clarithromycin phenotypic resistance was significantly lower as compared with genotypic resistance (18.4% versus 37.6%, P < 0.001). A concordance between the two methods was present in 71.2% of cases. A significant difference in the eradication rate was seen between clarithromycin-susceptible and -resistant strains, when assessed with either Etest (92.4% versus 55.5%, P < 0.001) or a PCR-based method (94.5% versus 70.9%; P < 0.001). Of note, the eradication rate showed the lowest value (30.7%) when phenotypic bacterial resistance was genetically linked to the A2143G point mutation.

CONCLUSIONS

This study showed that: (i) there is a relevant discordance between the two methods; and (ii) phenotypic clarithromycin resistance markedly reduces H. pylori eradication when it is linked to a specific point mutation.

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.

Dual-priming oligonucleotide-based multiplex PCR for the detection of Helicobacter pylori and determination of clarithromycin resistance with gastric biopsy specimens

BACKGROUND

Assessment of Helicobacter pylori (H. pylori) clarithromycin resistance has rarely been performed routinely despite an increasing resistance rate. Our aim was to develop and evaluate the use of dual-priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) to detect point mutations in the 23S rRNA gene responsible for clarithromycin resistance of H. pylori.

MATERIALS AND METHODS

Gastric biopsy specimens from 212 untreated patients with dyspepsia were examined by culture, histology, and DPO-based multiplex PCR. A disk diffusion test and E-test were used for performing phenotypic antibiotic susceptibility tests.

RESULTS

Among the biopsy specimens tested, 22.2% (47/212), 42.5% (90/212), and 41.5% (88/212) of the specimens were classified as H. pylori positive by culture, histology, and DPO-based multiplex PCR, respectively. Among 96 strains identified by either culture or DPO-based multiplex PCR, 80 strains were clarithromycin-susceptible and 16 strains (16.7%) were clarithromycin-resistant. There was 94.1% (32/34) concordance between phenotypic susceptibility tests and DPO-based multiplex PCR. In two patients with discrepant results, only DPO-based multiplex PCR detected clarithromycin-resistant strains. DPO-based multiplex PCR identified additional 49 clarithromycin-resistant or clarithromycin-susceptible H. pylori among 165 culture-negative specimens.

CONCLUSIONS

DPO-based multiplex PCR can be used as a practical method for the detection of H. pylori infection and the determination of clarithromycin susceptibility in addition to phenotypic antimicrobial susceptibility tests.

Cumulative H. pylori eradication rates in clinical practice by adopting first and second-line regimens proposed by the Maastricht III consensus and a third-line empirical regimen

OBJECTIVES

The European Helicobacter Study Group has recently issued the current concepts in the management of Helicobacter pylori infection (Maastricht III Consensus Report, 2005). The aim of the study was to examine the cumulative H. pylori eradication rates that can be achieved in clinical practice by adopting first and second regimens as proposed by the Maastricht III consensus and a third-line empirical levofloxacin-based regimen.

METHODS

H. pylori-positive patients were treated initially with a first-line eradication triple regimen consisting of omeprazole, amoxicillin, and clarithromycin and subsequently with a second-line quadruple regimen consisting of omeprazole, bismuth, metronidazole, and tetracycline. Finally, after two previous H. pylori eradication failures, patients received omeprazole, amoxicillin, and levofloxacin, as a third-line empirical strategy. The success rate was calculated by both intention-to-treat (ITT) and per protocol (PP) analyses.

RESULTS

In total, 540 consecutive H. pylori-positive patients received first-line treatment (omeprazole, amoxicillin, and clarithromycin). H. pylori were eradicated in 380 patients and 40 patients were withdrawn (ITT, 70.3%; PP, 76%). The remaining 120 H. pylori-positive patients received second-line treatment (omeprazole, bismuth, metronidazole, and tetracycline). H. pylori were eradicated in 83 patients and 7 patients were withdrawn (ITT, 69.1%; PP, 73.45%). Finally, the remaining 30 H. pylori-positive patients received third-line treatment (omeprazole, amoxicillin, and levofloxacin). H. pylori were eradicated in 21 patients and 0 patients were withdrawn (ITT, 70%; PP, 70%). Thus, out of 540 patients initially included in the study, H. pylori were eradicated in 484 patients, 47 were withdrawn, and only 9 remained positive. These results give 89.6% ITT and 98.1% PP cumulative H. pylori eradication rates.

CONCLUSIONS

By adopting first- and second-line regimens, as proposed by the Maastricht III consensus and a third-line levofloxacin-based empirical regimen, high cumulative H. pylori eradication rates can be achieved. Thus, a substantial number of cultures to determine sensitivity to antibiotics can be avoided with beneficial consequences concerning cost.

“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.

Helicobacter pylori eradication therapy: indications, efficacy and safety

BACKGROUND

Helicobacter pylori infects up to half of the world's population. It remains the major cause of peptic ulcer disease and is recognised as a carcinogen for its role in gastric carcinogenesis. Successful eradication of the bacteria is associated with improved health outcomes including fewer dyspeptic symptoms, reduced peptic ulcer recurrence and rebleeding, reduced peptic ulcer risk with NSAIDs and as a cure for low-grade gastric MALT lymphoma. The risk of gastric cancer is reduced in those without premalignant mucosal abnormalities at the time of eradication.

OBJECTIVE

This review outlines the current indications and options for therapy of H. pylori with particular reference to drug-induced adverse events associated with treatment.

METHODS

The indications for H. pylori eradication are evidence-based and in accordance with recent consensus statements and recommendations. The eradication treatment is based on numerous clinical trials and meta-analyses.

RESULTS/CONCLUSION

Eradication therapy, in general, is safe and well tolerated. Antibiotic therapy may be associated with significant drug adverse reactions, especially gastrointestinal symptoms.

Empirical rescue therapy after Helicobacter pylori treatment failure: a 10-year single-centre study of 500 patients

BACKGROUND

Several 'rescue' therapies have been recommended to eradicate Helicobacter pylori, but they still fail in >20% of the cases, and these patients constitute a therapeutic dilemma.

AIM

To evaluate the efficacy of different 'rescue' therapies empirically prescribed during 10 years to 500 patients in whom at least one eradication regimen had failed to cure H. pylori infection.

DESIGN

Prospective single-centre study.

PATIENTS

Consecutive patients in whom at least one eradication regimen had failed.

INTERVENTION

Rescue regimens included: (i) quadruple therapy with omeprazole-bismuth-tetracycline-metronidazole; (ii) ranitidine bismuth citrate-tetracycline-metronidazole; (iii) omeprazole-amoxicillin-levofloxacin; and (iv) omeprazole-amoxicillin-rifabutin. Antibiotic susceptibility was unknown (rescue regimens were chosen empirically).

OUTCOME

Eradication was defined as a negative (13)C-urea breath test 4-8 weeks after completing therapy.

RESULTS

Five hundred patients were included (76% functional dyspepsia, 24% peptic ulcer). Compliance rates with first-, second- and third-line regimens were 92%, 92%, and 95%, respectively. Adverse effects were reported by 30%, 37%, and 55% of the patients receiving second-, third-, and fourth-line regimens. Overall, H. pylori cure rates with the second-, third-, and fourth-line rescue regimens were 70%, 74%, and 76%, respectively. Cumulative H. pylori eradication rate with four successive treatments was 99.5%.

CONCLUSION

It is possible to construct an overall treatment strategy to maximize H. pylori eradication, on the basis of administration of four consecutive empirical regimens; thus, performing bacterial culture even after a second or third eradication failure may not be necessary.

"Cervia II Working Group Report 2006": guidelines on diagnosis and treatment of Helicobacter pylori infection in Italy

Proper management of Helicobacter pylori infection in clinical practice--when supported by evidence-based data--is expected to produce substantial cost-efficacy advantages. This consideration has prompted the Cervia Working Group to organise a meeting of experts to update the National Guidelines on the diagnosis and treatment of H. pylori infection in Italy. Recommendations in the new European Guidelines were considered in the National setting, here in the light of factors such as the incidence of gastric cancer and gastric lymphoma, the accessibility to different diagnostic tools, the prevalence of bacterial resistance against antibiotics, and the availability of different drugs. The main revisions in respect to the previous guidelines include H. pylori eradication in non-ulcer dyspepsia patients and in non-steroidal, anti-inflammatory drug users, as well as in patients with idiopathic thrombocytopenic purpura and iron deficiency anaemia. The stool antigen test is now accepted as a valid test for confirmation of H. pylori eradication following therapy. New therapeutic approaches have been recommended for both first- (sequential therapy) and second-line (levofloxacin-based) treatment in our country.

Third-line rescue therapy with levofloxacin is more effective than rifabutin rescue regimen after two Helicobacter pylori treatment failures

BACKGROUND

In patients with a first eradication failure, a second (rescue) therapy still fails in > 20% of cases.

AIM

To compare rifabutin and levofloxacin rescue regimens in patients with two consecutive Helicobacter pylori eradication failures.

METHODS

Patients, in whom first treatment with omeprazole-clarithromycin-amoxicillin and a second trial with omeprazole-bismuth-tetracycline-metronidazole (or ranitidine bismuth citrate with these antibiotics) had failed, received 10 days of treatment with either rifabutin (150 mg b.d.) or levofloxacin (500 mg b.d.), plus amoxicillin (1 g b.d.) and omeprazole (20 mg b.d.). Cure rates were evaluated by the (13)C-urea breath test.

RESULTS

Twenty patients received rifabutin, and 20 levofloxacin. All the patients returned for follow-up. Compliance in the rifabutin group was 100%. Four patients in the levofloxacin group did not take the medication correctly (in two cases due to adverse effects: myalgia and rash). Side effects in the rifabutin and levofloxacin groups were reported in 60% and 50% of the cases, respectively. Five patients (25%) treated with rifabutin presented with leucopenia, and six (30%) treated with levofloxacin presented with myalgias. Per-protocol cure rates were 45% (95% confidence interval, 26-66%) in the rifabutin group, and 81% (57-93%) in the levofloxacin group (P < 0.05). Intention-to-treat cure rates were, 45% (26-66%) and 85% (64-95%), respectively (P < 0.01).

CONCLUSIONS

After two previous H. pylori eradication failures, a 10-day triple levofloxacin-based rescue regimen is more effective than the same regimen with rifabutin.