Antimicrobial resistance of H. pylori to the outcome of 10-days vs. 7-days Moxifloxacin based therapy for the eradication: a randomized controlled trial

Optimization Strategies Aimed to Increase the Efficacy of Helicobacter pylori Eradication Therapies with Quinolones

H. pylori infection is the main cause of gastritis, gastroduodenal ulcer disease, and gastric cancer. Fluoroquinolones such as levofloxacin, or more recently moxifloxacin or sitafloxacin, are efficacious alternatives to standard antibiotics for H. pylori eradication. The aim of the present review is to summarize the role of quinolone-based eradication therapies, mainly focusing on the optimization strategies aimed to increase their efficacy. Several meta-analyses have shown that, after failure of a first-line eradication treatment, a levofloxacin-containing rescue regimen is at least equally effective, and better tolerated, than the generally recommended bismuth quadruple regimen. Compliance with the levofloxacin regimens is excellent, and the safety profile is favourable. Higher cure rates have been reported with longer treatments (>10-14 days), and 500 mg levofloxacin daily is the recommended dose. Adding bismuth to the standard triple regimen (PPI-amoxicillin-levofloxacin) has been associated with encouraging results. Unfortunately, resistance to quinolones is easily acquired and is increasing in most countries, being associated with a decrease in the eradication rate of H. pylori. In summary, a quinolone (mainly levofloxacin)-containing regimen is an encouraging second-line (or even third-line) strategy, and a safe and simple alternative to bismuth quadruple therapy in patients whose previous H. pylori eradication therapy has failed.

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

BACKGROUND & AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Susceptibility of Helicobacter pylori to antibiotics in Chinese patients

OBJECTIVE

Antibiotic resistance to Helicobacter pylori (H. pylori) has been increasing worldwide. The study aimed to evaluate in vitro susceptibility and resistance patterns to antibiotics in empirical H. pylori eradication regimens, and to determine the optimal antibiotics for treatment.

METHODS

H. pylori strains (n =181) were obtained from gastric biopsies of patients with upper gastrointestinal symptoms who underwent esophagogastroduodenoscopy from March to December 2013. The susceptibility of H. pylori strains to amoxicillin (AMX), metronidazole (MTZ), clarithromycin (CLR), amoxicillin-clavulanate (AMC), cephalothin (CEP), cefuroxime (CXM), cefixime (CFM), moxifloxacin (MFX) and minocycline (MNO) was determined.

RESULTS

Dual resistance to MTZ + CLR was detected in 48 (26.5%) isolates, MTZ + MFX in 94 (51.9%), and CLR + MFX in 49 (27.1%). Overall, 41 (22.7%) were resistant to MTZ + CLR + MFX. MTZ and CLR resistance rates were significantly associated with the history of H. pylori eradication but there was no significant difference in MFX resistance rates between treated and untreated patients (P = 0.674). No significant relationship was found between antibiotic resistance and patient's gender, age, endoscopic findings, inflammatory severity or gastric atrophy.

CONCLUSIONS

AMX, AMC, MNO and cephalosporins, but not MTZ, CLR and MFX, showed good in vitro anti-H. pylori activity. Among cephalosporins, CXM was the most active. H. pylori resistance is higher in patients with previous H. pylori eradication.

Two-week, high-dose proton pump inhibitor, moxifloxacin triple Helicobacter pylori therapy after failure of standard triple or non-bismuth quadruple treatments

BACKGROUND

Aim was to evaluate the efficacy and tolerability of a moxifloxacin-containing second-line triple regimen in patients whose previous Helicobacter pylori eradication treatment failed.

METHODS

Prospective multicentre study including patients in whom a triple therapy or a non-bismuth-quadruple-therapy failed. Moxifloxacin (400mg qd), amoxicillin (1g bid), and esomeprazole (40 mg bid) were prescribed for 14 days. Eradication was confirmed by (13)C-urea-breath-test. Compliance was determined through questioning and recovery of empty medication envelopes.

RESULTS

250 patients were consecutively included (mean age 48 ± 15 years, 11% with ulcer). Previous (failed) therapy included: standard triple (n = 179), sequential (n = 27), and concomitant (n = 44); 97% of patients took all medications, 4 were lost to follow-up. Intention-to-treat and per-protocol eradication rates were 82.4% (95% CI, 77-87%) and 85.7% (95% CI, 81-90%). Cure rates were similar independently of diagnosis (ulcer, 77%; dyspepsia, 82%) and previous treatment (standard triple, 83%; sequential, 89%; concomitant, 77%). At multivariate analysis, only age was associated with eradication (OR = 0.957; 95% CI, 0.933-0.981). Adverse events were reported in 25.2% of patients: diarrhoea (9.6%), abdominal pain (9.6%), and nausea (9.2%).

CONCLUSION

14-day moxifloxacin-containing triple therapy is an effective and safe second-line strategy in patients whose previous standard triple therapy or non-bismuth quadruple (sequential or concomitant) therapy has failed, providing a simple alternative to bismuth quadruple regimen.

Pharmacological therapy used in the elimination of Helicobacter pylori infection: A review

The optimal therapy for Helicobacter pylori (H. pylori) infection should combine a high cure rate and a short treatment duration with a favorable side-effect profile and should maintain a low cost. Several strategies have been proposed to increase the H. pylori eradication rate, including the extension of the treatment duration to 14 d, the use of a four-drug regimen (quadruple, sequential, and concomitant treatments), and the use of novel antibiotics, such as levofloxacin. However, triple therapy remains the most widely accepted first-line treatment regimen in Brazil and the United States and throughout Europe. Because this therapy is limited by resistance to clarithromycin, other therapeutic regimens have been investigated worldwide. This review describes the current literature involving studies directly comparing these different therapies and their efficacies.

The efficacy of moxifloxacin-containing triple therapy after standard triple, sequential, or concomitant therapy failure for Helicobacter pylori eradication in Korea

Background/Aims

Retreatment after initial treatment failure for Helicobacter pylori is very challenging. The purpose of this study was to evaluate the efficacies of moxifloxacin-containing triple and bismuth-containing quadruple therapy.

Methods

A total of 151 patients, who failed initial H. pylori treatment, were included in this retrospective cohort study. The initial regimens were standard triple, sequential, or concomitant therapy, and the efficacies of the two following second-line treatments were evaluated: 7-day moxifloxacin-containing triple therapy (rabeprazole 20 mg twice a day, amoxicillin 1,000 mg twice a day, and moxifloxacin 400 mg once daily) and 7-day bismuth-containing quadruple therapy (rabeprazole 20 mg twice a day, tetracycline 500 mg 4 times a day, metronidazole 500 mg 3 times a day, and tripotassium dicitrate bismuthate 300 mg 4 times a day).

Results

The overall eradication rates after moxifloxacin-containing triple therapy and bismuth-containing quadruple therapy were 69/110 (62.7%) and 32/41 (78%), respectively. Comparison of the two regimens was performed in the patients who failed standard triple therapy, and the results revealed eradication rates of 14/28 (50%) and 32/41 (78%), respectively (p=0.015). The frequency of noncompliance was not different between the two groups, and there were fewer adverse effects in the moxifloxacin-containing triple therapy group (2.8% vs 7.3%, p=0.204 and 25.7% vs 43.9%, p=0.031, respectively).

Conclusions

Moxifloxacin-containing triple therapy, a recommended second-line treatment for initial concomitant or sequential therapy failure, had insufficient efficacy.

Functional and molecular surveillance of Helicobacter pylori antibiotic resistance in Kuala Lumpur

BACKGROUND

Helicobacter pylori is the etiological agent for diseases ranging from chronic gastritis and peptic ulcer disease to gastric adenocarcinoma and primary gastric B-cell lymphoma. Emergence of resistance to antibiotics possesses a challenge to the effort to eradicate H. pylori using conventional antibiotic-based therapies. The molecular mechanisms that contribute to the resistance of these strains have yet to be identified and are important for understanding the evolutional pattern and selective pressure imposed by the environment.

METHODS AND FINDINGS

H. pylori was isolated from 102 patients diagnosed with gastrointestinal diseases, who underwent endoscopy at University Malaya Medical Centre (UMMC). The isolates were tested for their susceptibility on eleven antibiotics using Etest. Based on susceptibility test, 32.3% of the isolates were found to have primary metronidazole resistance; followed by clarithromycin (6.8%) and fluoroquinolones (6.8%). To further investigate the resistant strains, mutational patterns of gene rdxA, frxA, gyrA, gyrB, and 23S rRNA were studied. Consistent with the previous reports, metronidazole resistance was prevalent in the local population. However, clarithromycin, fluoroquinolone and multi-drug resistance were shown to be emerging. Molecular patterns correlated well with phenotypic data. Interestingly, multi-drug resistant (MDR) strains were found to be associated with higher minimum inhibitory concentration (MIC) than their single-drug resistant (SDR) counterparts. Most importantly, clarithromycin-resistant strains were suggested to have a higher incidence for developing multi-drug resistance.

CONCLUSION

Data from this study highlighted the urgency to monitor closely the prevalence of antibiotic resistance in the Malaysian population; especially that of clarithromycin and multi-drug resistance. Further study is needed to understand the molecular association between clarithromycin resistance and multi-drug resistance in H. pylori. The report serves a reminder that a strict antibiotic usage policy is needed in Malaysia and other developing countries (especially those where H. pylori prevalence remained high).

Resistotype of Helicobacter pylori isolates: the impact on eradication outcome

Antibiotic resistance is increasing worldwide, and it has been regarded as the main factor reducing the efficacy of Helicobacter pylori therapy. The aim of this study was to determine the phenotype and genotype of antibiotic-resistant strains of H. pylori in the Malaysian population and to evaluate the impact of antibiotic resistance to eradication outcome. One hundred and sixty-one H. pylori isolates were analysed in this study. Metronidazole, clarithromycin, fluoroquinolone, amoxicillin and tetracycline susceptibilities were determined by Etest. PCR followed by DNA sequencing was carried out to determine mutations. The medical records of the patients infected with resistant strains were reviewed to determine the eradication outcome. Metronidazole resistance was encountered in 36.6 % of H. pylori isolates, whereas clarithromycin and fluoroquinolone resistance was observed in 1.2  and 1.9 % of isolates, respectively. All strains tested were susceptible to amoxicillin and tetracycline. Frameshift and nonsense mutations in rdxA and frxA genes resulting in stop codons contributed to metronidazole resistance, which leads to reduced eradication efficacy. A2142G and A2143G mutations of 23S rRNA were identified as causing failure of the eradication therapy. Mutation at either codon 87 or 91 of the gyrA gene was identified in fluoroquinolone-resistant strains. However, the effect of resistance could not be assessed. This study showed that frameshift and nonsense mutations in rdxA or frxA genes and point mutations in the 23S rRNA affected the efficacy of H. pylori eradication therapy.

The efficacy of moxifloxacin-based triple therapy in treatment of Helicobacter pylori infection: a systematic review and meta-analysis of randomized clinical trials

Recent evidence shows that moxifloxacin could exert an antimicrobial effect against Helicobacter pylori in both in vitro and in vivo models. To systematically evaluate whether moxifloxacin-containing triple therapy could improve eradication rates and reduce side effects in first-line or second-line anti-H. pylori treatment, eligible articles were identified by searches of electronic databases. We included all randomized trials comparing moxifloxacin-based triple therapy with standard triple or quadruple therapy during H. pylori eradication treatment. Statistical analysis was performed with Review Manager 5.0.10. Subanalysis/sensitivity analysis was also performed. We identified seven randomized trials (n=1263). Pooled H. pylori eradication rates were 79.03% (95%CI: 75.73-82.07) and 68.33% (95%CI: 64.44-72.04) for patients with moxifloxacin-based triple therapy or with standard triple or quadruple therapy, respectively (intention-to-treat analysis). The odds ratio (OR) was 1.82 (95%CI: 1.17-2.81), the occurrence of total side effects was 15.23% (95%CI: 12.58-18.20) and 27.17% (95%CI: 23.64-30.92) for groups with or without moxifloxacin, and the summary OR was 0.45 (95%CI: 0.26-0.77). In subgroup analyses, we noted that the second-line eradication rate in the moxifloxacin group was significantly higher than that in the quadruple therapy group (73.33 vs 60.17%, OR: 1.78, 95%CI: 1.16-2.73, P<0.001). However, there was no difference in first-line eradication treatment. Findings from this meta-analysis suggest that moxifloxacin-based triple therapy is more effective and better tolerated than standard triple or quadruple therapy. Therefore, a moxifloxacin-based triple regimen should be used in the second-line treatment of H. pylori infection.

Guidelines for treatment of Helicobacter pylori in the East and West

Infection with Helicobacter pylori remains a major healthcare burden, with persistently high prevalence rates, especially in less-developed countries. H. pylori infection is causally related to non-malignant and malignant gastroduodenal diseases, such as peptic ulcer diseases, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. Current international guidelines recommend a standard triple therapy as first-line therapy, including a proton pump inhibitor and a combination of amoxicillin and clarithromycin. Standard triple therapy has shown a decreasing efficacy over the years. The main reason is the increasing antibiotic resistance, particular to clarithromycin of H. pylori strains. Several new treatment options or modifications of already established regimens have been introduced to overcome treatment failure. In this article, we intend to report the reasons for treatment failure, and furthermore we give an overview of new treatment options as alternatives to the current treatment regimens. Finally, the strategy for the future is considered.

Increasing gastric juice pH level prior to anti-Helicobacter pylori therapy may be beneficial to the healing of duodenal ulcers

The aim of this study was to observe the efficacy of clarithromycin-based triple therapy for Helicobacter pylori (Hp)-infected duodenal ulcer when combined with different pH levels of gastric juices. A total of 160 patients with Hp-infected duodenal ulcers were randomly allocated into two groups. Patients in the treatment group (n=80) were administered a 20-mg dose of omeprazole twice daily for 1 week and then the treatment and control groups (n=80) received therapy for Hp infection and duodenal ulcers. We observed the ulcer healing stage, the content of anti-Hp IgA in gastric juice and the Hp eradication rate before and after proton pump inhibitor therapy in the two groups. Results revealed that the Hp eradication rate in the treatment group was 93% compared with 81% in the control group, and the difference was statistically significant (P<0.05). The ulcer healing rate in the treatment group was 93%, compared with 70% in the control group (P<0.05). A positive linear correlation was observed between gastric pH and the content of anti-Hp IgA in gastric juice (P<0.05). Increasing gastric pH prior to anti-Hp therapy may be beneficial to the eradication of Hp and for promoting the healing of duodenal ulcers.

Quadruple therapy with moxifloxacin and bismuth for first-line treatment of Helicobacter pylori

AIM: To compare triple therapy vs quadruple therapy for 10 d as first-line treatment of Helicobacter pylori (H. pylori) infection.

METHODS: Consecutive H. pylori positive patients never treated in the past for this infection were randomly treated with triple therapy of pantoprazole (PAN) 20 mg bid, amoxicillin (AMO) 1 g bid and moxifloxacin (MOX) 400 mg bid for 10 d (PAM) or with quadruple therapy of PAN 20 mg bid, AMO 1 g bid, MOX 400 mg bid and bismuth subcitrate 240 mg bid for 10 d (PAMB). All patients were found positive at 13 C-Urea breath test (UBT) performed within ten days prior to the start of the study. A successful outcome was confirmed with an UBT performed 8 wk after the end of treatment. χ² analysis was used for statistical comparison. Per protocol (PP) and intention-to-treat (ITT) values were also calculated.

RESULTS: Fifty-seven patients were enrolled in the PAM group and 50 in the PAMB group. One patient in each group did not return for further assessment. Eradication was higher in the PAMB group (negative: 46 and positive: 3) vs the PAM group (negative: 44 and positive: 12). The H. pylori eradication rate was statistically significantly higher in the PAMB group vs the PAM group, both with the PP and ITT analyses (PP: PAMB 93.8%, PAM 78.5%, P < 0.02; ITT: PAMB 92%, PAM 77.1 %, P <0.03).

CONCLUSION: The addition of bismuth subcitrate can be considered a valuable adjuvant to triple therapy in those areas where H. pylori shows a high resistance to fluoroquinolones.

Treatment of Helicobacter pylori

PURPOSE OF REVIEW

The article will give an overview on reasons for treatment failure and tries to show new concepts for Helicobacter pylori treatment.

RECENT FINDINGS

Several new treatment options or modifications of already established regimens have been introduced to overcome treatment failure. Antibiotic resistance to H. pylori is the key factor for treatment failure. At the moment, standard triple therapy remains the primary choice in regions with proven low clarithromycin resistance rates. In areas with high clarithromycin resistance, four drug treatment regimens, including quadruple and sequential therapy, have proven the best results as first-line regimens. The options for second-line treatment regimens are manifold. Second-line treatment regimens need to be adapted accurately to local resistance rates.

SUMMARY

Treatment of H. pylori infection is challenged by a dramatic fall in eradication rates all over the world. Newer regimens have been introduced including sequential, quadruple therapies and those regimens provide promising results, but the knowledge about local resistance rates remains the key to an effective therapy.

Should quinolones come first in Helicobacter pylori therapy?

New generations of fluoroquinolones, like levofloxacin and moxifloxacin, exhibit a broad-spectrum activity against Gram-positive and Gram-negative bacteria, and have been successfully introduced into the treatment of Helicobacter pylori infection. Based on a large body of evidence, current guidelines recommend the use of levofloxacin- or moxifloxacin-containing proton-pump inhibitor (PPI) triple therapies in second-line or rescue treatment of H. pylori infection. The efficacy of standard PPI triple therapies has substantially declined during the last decade, mainly due to increasing resistance against the key antibiotics clarithromycin and metronidazole. Therefore, alternative strategies for first-line therapy of H. pylori infection have been evaluated in a considerable number of clinical trials including sequential regimens, nonbismuth quadruple regimens, and quinolone-containing PPI triple therapy regimens. The aim of this paper is to summarize the current body of evidence of levofloxacin- and moxifloxacin-containing regimens in first-line treatment of H. pylori infection, and to discuss the risks and benefits of these strategies in the light of increasing resistance of H. pylori to quinolones.

The effectiveness of systemic eradication therapy against oral Helicobacter pylori

BACKGROUND

Helicobacter pylori infection is associated with numerous gastroduodenal diseases. The oral cavity could be a potential extragastric reservoir for H. pylori, and oral H. pylori might cause gastric reinfection after the eradication therapy. The aim of the study was to evaluate the presence of H. pylori in oral cavity of patients with gastric H. pylori infection and to examine the effectiveness of the eradication therapy against H. pylori in stomach and in the oral cavity.

METHODS

Fifty-six patients with chronic periodontitis and gastric H. pylori were enrolled in the study. Gastric H. pylori infection was determined using (13) C-urea breath test before and 3 months after eradication therapy. The presence of the oral H. pylori was assessed using polymerase chain reaction before and 3 months after eradication therapy. The 1-week eradication therapy consisted of amoxycilin 1 g, clarithromycin 500 mg, and proton pump inhibitor 20 mg twice a day.

RESULTS

Of 56 subjects with gastric infection, 23 (41.1%) harbored H. pylori in the oral cavity. Eradication rate in stomach was 78.3%, whereas in the oral cavity, H. pylori was not detected from any sample after the eradication therapy.

CONCLUSION

Almost half of the patients with gastric H. pylori harbored the bacterium in the oral cavity. After the eradication therapy, H. pylori was not detected in the oral cavity, what suggests high effectiveness of the therapy protocol in the oral cavity, or it is possible that oral H. pylori is of a transient character.