Culture-guided treatment approach for Helicobacter pylori infection: Review of the literature

A whole genome sequencing-based assay to investigate antibiotic susceptibility and strain lineage of Helicobacter pylori

Helicobacter pylori (H. pylori) antibiotic resistance has been widespread and increasing worldwide, which presented a significant challenge to the successful eradication of H. pylori infection. Identification of antibiotic resistance and exploration of potential resistance mechanisms are thus necessary for effective treatment. For this purpose, we herein develop a whole genome sequencing (WGS) assay based on next-generation sequencing (NGS) to detect the entire genome of 73 H. pylori strains isolated from gastric mucosa of patients in Tianjin, China, and analyzed the association between single-nucleotide polymorphism (SNP) in resistance-related genes and phenotypic sensitivity. We discovered the consistent relationship between genotypic and phenotypic resistance by A2143C/G in 23S rRNA for clarithromycin (Kappa: 0.882), N87K/I in gyrA for levofloxacin (Kappa: 0.883), and wild-type of pbp1 for amoxicillin. In addition, we obtained 4 super-resistant clinical strains of H. pylori, which formed thick, sticky biofilms, were extremely resistant to all antibiotics regardless of the present of mutations in antibiotic targets sites. Therefore, biofilm formation is also a mechanism of drug resistance, and biofilm-related proteins or genes are also expected to be used as screening markers for H. pylori resistance.

Amoxicillin, gemifloxacin and rabeprazole, as first-line Helicobacter pylori therapy in clinical practice: A pilot study

Success in eradication of H. pylori is decreasing due to increasing resistant strains. In particular, side-effects due to 4-agent treatment multiple drug use are observed and treatment compliance decreases. The aim of this study was to evaluate the efficacy, reliability, and side-effect profile of the combination of amoxicillin and rabeprazole with gemifloxacin, which is a new generation quinolone, in the treatment of H. pylori infection. This study was conducted on 71 naive patients who received H. pylori eradication. All the patients were administered treatment of Amoxicillin (1000 mg twice a day) + Gemifloxacin (320 mg once a day) + rabeprazole (20 mg twice a day) for 7 days. Drug compliance and treatment tolerance were evaluated after finishing the treatment. At 1 month after the end of the treatment, H. pylori eradication was evaluated in all the patients by examining H. pylori antigen in the feces. In the evaluation after treatment, H. pylori eradication was obtained in 63 (88.7%) patients and eradication was not obtained in 8 (11.3%) patients. The treatment was not completed by 2 patients because of side-effects and noncompliance, so after exclusion of these 2 patients, successful H. pylori eradication was obtained in 63 (91.3%) of 69 patients who completed the treatment. Side-effects were seen in a total of 9 (12.7%) patients. Diarrhea, bloating, abdominal pain, and nausea-vomiting were seen in some patients, but no reflux, constipation, skin rash, listlessness-fatigue, headache, dizziness, palpitations, dry mouth, or weight loss was seen in any patient. In regions with high resistance to clarithromycin and metronidazole in particular, the combination of gemifloxacin with amoxicillin and rabeprazole can be considered for use in first-stage treatment as both the efficacy and tolerability are high.

Sequential therapy versus quadruple therapy for Helicobacter pylori eradication: A prospective double-blinded randomized controlled trial

Backgrounds and Aims

This controlled randomized clinical trial was designed to compare effectiveness, side effects, and severity of symptoms before and after therapy between quadruple (QT) and sequential regimens (SQ) for Helicobacter Pylori (H. pylori).

Methods

Patients were randomly allocated into two groups. Group A received a 14-day QT including pantoprazole 40 mg q12 h, bismuth subcitrate 240 mg q12 h, clarithromycin 500 mg q12 h, and amoxicillin 1000 mg q12 h and group B received ST including pantoprazole 40 mg q12 h and amoxicillin 1000 mg q12 h for the initial 5 days followed by pantoprazole 40 mg q12 h, clarithromycin 500 mg q12 h and tinidazole 500 mg q12 h for the next 5 days. Adverse drug reactions and patients' compliance were assessed after finishing the treatment course and also 4 weeks after. All patients were naive, therefore ST and QT were first-line therapies. To evaluate severity of symptoms we used Short-Form Leeds Dyspepsia Questionnaire (SF-LDQ) before taking the first dose of regimens, at the end of therapy, and also 4 weeks after (follow-up).

Results

The mean age in Group A (n = 83) was 48.55 ± 12.56 and 47.24 ± 12.78 in Group B (n = 79). No statistically significant differences were observed between the two groups regarding age, gender, endoscopic findings, and also eradication rate. The analysis demonstrated a significant decrease in SF-LDQ score between baseline and after therapy and baseline and follow-up in both regimen groups. Both regimens were well tolerated by the majority of patients, and there were no significant differences between the two groups in terms of adverse drug reactions.

Conclusion

This study showed that ST can be used as an alternative first-line therapy to QT in patients with H. pylori infection.

The Influence of Helicobacter pylori on Human Gastric and Gut Microbiota

Helicobacter pylori is a Gram-negative bacterium that is able to colonize the human stomach, whose high prevalence has a major impact on human health, due to its association with several gastric and extra-gastric disorders, including gastric cancer. The gastric microenvironment is deeply affected by H. pylori colonization, with consequent effects on the gastrointestinal microbiota, exerted via the regulation of various factors, including gastric acidity, host immune responses, antimicrobial peptides, and virulence factors. The eradication therapy required to treat H. pylori infection can also have detrimental consequences for the gut microbiota, leading to a decreased alpha diversity. Notably, therapy regimens integrated with probiotics have been shown to reduce the negative effects of antibiotic therapy on the gut microbiota. These eradication therapies combined with probiotics have also higher rates of eradication, when compared to standard treatments, and are associated with reduced side effects, improving the patient's compliance. In light of the deep impact of gut microbiota alterations on human health, the present article aims to provide an overview of the complex interaction between H. pylori and the gastrointestinal microbiota, focusing also on the consequences of eradication therapies and the effects of probiotic supplementation.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Helicobacter pylori Antibiotic Resistance in Egypt: A Single-Center Study

Purpose

Helicobacter pylori (H. pylori) is the most common human bacterial infection worldwide, infecting approximately half of the world’s population. Although antibiotic use is indicated for H. pylori eradication, the recommended type of antibiotic varies from country to country according to the H. pylori resistance pattern; developing countries, such as Egypt, may have different patterns than developed countries. We evaluated the antibiotic resistance of H. pylori in Egypt.

Methods

This cross-sectional study included 134 adult patients with upper gastrointestinal (GI) complaints. Patients with a history of PPI during the last 2 weeks or antibiotics during the last 4 weeks before endoscopy were excluded. Upper GI endoscopies were performed and biopsies were collected for histopathology and H. pylori culture. Demographic, clinical, and endoscopic data were also collected. Antimicrobial susceptibility testing for H. pylori was performed for nine therapeutically relevant antibiotics using the Kirby–Bauer disc diffusion method.

Results

The H. pylori antibiotic resistance rates were as follows: moxifloxacin, 10%; doxycycline, 15%; levofloxacin, 20%; clarithromycin, 40%; azithromycin, 40%; erythromycin, 65%; rifampicin, 90%; amoxicillin, 95%; and metronidazole, 100%. Dual resistance rates were 40% for amoxicillin/clarithromycin, 40% for metronidazole/clarithromycin, and 95% for amoxicillin/metronidazole.

Conclusion

In Egyptian patients, H. pylori had >90% resistance to metronidazole and amoxicillin; modest resistance to erythromycin, azithromycin, and clarithromycin; and low resistance to moxifloxacin, and levofloxacin (≤20%). Dual resistance was high for amoxicillin/clarithromycin and amoxicillin/metronidazole, which prefers using quinolones rather than clarithromycin or metronidazole for first-line treatment of H. pylori in Egypt.

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

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

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.

Antibiotic Resistance Prevalence and Trends in Patients Infected with Helicobacter pylori in the Period 2013-2020: Results of the European Registry on H. pylori Management (Hp-EuReg)

Background: Bacterial antibiotic resistance changes over time depending on multiple factors; therefore, it is essential to monitor the susceptibility trends to reduce the resistance impact on the effectiveness of various treatments. Objective: To conduct a time-trend analysis of Helicobacter pylori resistance to antibiotics in Europe. Methods: The international prospective European Registry on Helicobacter pylori Management (Hp-EuReg) collected data on all infected adult patients diagnosed with culture and antimicrobial susceptibility testing positive results that were registered at AEG-REDCap e-CRF until December 2020. Results: Overall, 41,562 patients were included in the Hp-EuReg. Culture and antimicrobial susceptibility testing were performed on gastric biopsies of 3974 (9.5%) patients, of whom 2852 (7%) were naive cases included for analysis. The number of positive cultures decreased by 35% from the period 2013–2016 to 2017–2020. Concerning naïve patients, no antibiotic resistance was found in 48% of the cases. The most frequent resistances were reported against metronidazole (30%), clarithromycin (25%), and levofloxacin (20%), whereas resistances to tetracycline and amoxicillin were below 1%. Dual and triple resistances were found in 13% and 6% of the cases, respectively. A decrease (p < 0.001) in the metronidazole resistance rate was observed between the 2013–2016 (33%) and 2017–2020 (24%) periods. Conclusion: Culture and antimicrobial susceptibility testing for Helicobacter pylori are scarcely performed (<10%) in Europe. In naïve patients, Helicobacter pylori resistance to clarithromycin remained above 15% throughout the period 2013–2020 and resistance to levofloxacin, as well as dual or triple resistances, were high. A progressive decrease in metronidazole resistance was observed.

Detection of Helicobacter pylori by invasive tests in adult dyspeptic patients and antibacterial resistance to six antibiotics, including rifampicin in Turkey. Is clarithromycin resistance rate decreasing?

Background/aim

The prevalence of Helicobacter pylori is reported to be roughly 80% in Turkey, and only very few culture-based studies are available on antibacterial resistance in adult dyspeptic patients. This study was carried out in adult dyspeptic patients with an aim to: (i) detect H. pylori by invasive tests (culture, polymerase chain reaction, and histopathology) and (ii) determine the current resistance rates of H. pylori isolates to six antibiotics, including rifampicin.

Materials and methods

This study was conducted in 422 adult dyspeptic patients. The presence of H. pylori was demonstrated by culture, polymerase chain reaction, and the histopathology of gastric biopsy material. Antibacterial susceptibility was determined with the E-test.

Results

The mean age of the patients was 50 ± 15 (range 18–90), and 265 (63%) of them were female. By culture, polymerase chain reaction, and histopathology, the presence of H. pylori was detected at rates of 35% (148/422), 67% (281/422), and 53% (224/422), respectively. The prevalence of H. pylori was determined as 75.6% (319/422). Metronidazole, levofloxacin, clarithromycin, and rifampicin resistance rates were 62%, 36%, 19%, and 12%, respectively. Monodrug, dual-drug, and multidrug resistance rates were ascertained as 36.9%, 29.4%, and 10.5%, respectively. All of the isolates were susceptible to amoxicillin and tetracycline.

Conclusion

This study revealed the current prevalence of H. pylori in adult dyspeptic patients as 75.6%, and thereby, showed that infection with this pathogen remains highly prevalent. Although resistance to metronidazole and levofloxacin has increased over time, clarithromycin resistance rate has decreased. The high levels of resistance to metronidazole and levofloxacin limit the empirical use of these antibiotics in the eradication protocol. Owing to the low level of resistance determined for rifampicin, this antibiotic could be included in the eradication protocol, in the event of the need for rescue therapy in Turkey.

Role of Antimicrobial Susceptibility Testing before First-Line Treatment Containing Clarithromycin for Helicobacter pylori Eradication in the Clinical Setting

BACKGROUND

Checking Helicobacter pylori susceptibility tests in the clinical setting before first-line treatment is considered difficult. We compared susceptibility-guided therapy (SGT) with empirical therapy (ET) as a first-line treatment containing clarithromycin and investigated the eradication rate using antimicrobial susceptibility testing (AST).

METHODS

257 patients with H. pylori infection, with AST, performed before the eradication of clarithromycin-containing regimens were enrolled and divided into two groups: the SGT and ET groups.

RESULTS

Eradication rates in the SGT and ET groups were 85.4% and 58.4% (P < 0.01), respectively. In triple therapy (TT), eradication rates of the SGT and ET groups were 85.1% and 56.6% (P < 0.01), respectively. In sequential therapy (SET), eradication rates of the SGT and ET groups were 86.2% and 65.6% (P = 0.06), respectively. According to AST, TT had an eradication rate of 84.6% with strains susceptible to clarithromycin and amoxicillin and 11.1% with strains resistant to both. SET had an eradication rate of 89.5% with strains susceptible to clarithromycin, amoxicillin, and metronidazole, whereas it was 0% with strains resistant to clarithromycin and metronidazole.

CONCLUSIONS

SGT as first-line treatment improved eradication rates of TT and SET by 28.5 (P < 0.01) and 20.6 (P = 0.06) percent points, respectively, compared with ET.

Prospective comparative study of the treatment of Helicobacter pylori with antibiotic susceptibility testing-guided triple therapy compared to quadruple therapy with bismuth-metronidazole-tetracycline subcitrate

INTRODUCTION

the current indicated first-line treatment for Helicobacter pylori (H. pylori) infection is the quadruple therapy with bismuth (Pylera®), or the quadruple concomitant therapy without bismuth. The triple therapy was abandoned due to its low eradication rates, partly derived from an increase in antibiotic resistance. The aim of this study was to compare the H. pylori eradication rates guided by antibiotic susceptibility testing (AST) versus Pylera®.

METHODS

a specimen was taken prospectively for culture and antibiotic susceptibility testing (AST) from all patients diagnosed with H. pylori infection using gastroscopy, and they were randomized to receive triple therapy depending on the results of the AST, or quadruple therapy with Pylera®. The eradication rates of both groups were analyzed using fecal antigen. The adherence and side effects of the treatment were also analyzed.

RESULTS

of the 108 patients with H. pylori infection, 55 received Pylera® and 53 AST-guided triple therapy. The eradication rates were 92.7 % with Pylera® and 90.6 % in the AST-guided group, and the difference was statistically significant. There were also no differences found in adherence or side effects.

CONCLUSIONS

the treatment of H. pylori with AST-guided triple therapy is effective, especially in regions with high rates of antibiotic resistance.

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.

Optimizing proton pump inhibitors in Helicobacter pylori treatment: Old and new tricks to improve effectiveness

The survival and replication cycle of Helicobacter pylori (H. pylori) is strictly dependant on intragastric pH, since H. pylori enters replicative phase at an almost neutral pH (6-7), while at acid pH (3-6) it turns into its coccoid form, which is resistant to antibiotics. On these bases, it is crucial to increase intragastric pH by proton pump inhibitors (PPIs) when an antibiotic-based eradicating therapy needs to be administered. Therefore, several tricks need to be used to optimize eradication rate of different regimens. The administration of the highest dose as possible of PPI, by doubling or increasing the number of pills/day, has shown to be able to improve therapeutic outcome and has often proposed in rescue therapies, even if specific trials have not been performed. A pre-treatment with PPI before starting antibiotics does not seem to be effective, therefore it is discouraged. However, the choice of PPI molecule could have a certain weight, since second-generation substances (esomeprazole, rabeprazole) are likely more effective than those of first generation (omeprazole, lansoprazole). A possible explanation is due to their metabolism, which has been proven to be less dependent on cytochrome P450 (CYP) 2C19 genetic variables. Finally, vonoprazan, a competitive inhibitor of H+/K+-ATPase present on luminal membrane of gastric parietal cells has shown the highest efficacy, due to both its highest acid inhibition power and rapid pharmacologic effect. However current data come only from Eastern Asia, therefore its strong power needs to be confirmed outside this geographic area in Western countries as well as related to the local different antibiotic resistance rates.

Efficacy of tailored therapy for Helicobacter pylori eradication based on clarithromycin resistance and survey of previous antibiotic exposure: A single-center prospective pilot study

BACKGROUND

As the prevalence of antibiotic resistance is increasing, the effectiveness of traditional Helicobacter pylori (H pylori) therapies is gradually declining. We aimed to evaluate the efficacy of tailored therapy (dual priming oligonucleotide [DPO]-based multiplex PCR) and previous antibiotic exposure survey predicting for antibiotic resistance.

MATERIALS AND METHODS

Patients with H pylori infection who did not receive previous treatment were enrolled. The patients were divided into four groups (no resistance [NR] group, clarithromycin resistance [CLA-R] group, metronidazole-resistant [MET-R] group, and CLA- and MET-resistant [Dual-R] group) based on the results of dual priming oligonucleotide (DPO) polymerase chain reaction (PCR) and previous antibiotic exposure survey, and they were treated with tailored therapy based on antibiotic susceptibility.

RESULTS

Consecutive patients were distributed in the NR (n = 36, 70.6%), CLA-R (n = 9, 17.6%), and suspected MET-R (n = 6, 11.8%) group. The overall intention-to-treat/per-protocol eradication rate (ITT/PP) was 92.2%/94.0%. In the subgroup analysis, the ITT and PP of the NR, CLA-R, and MET-R groups were 94.4%/94.4%, 77.8%/87.5%, and 100.0%/100.0%, respectively. Total of 31 patients in all subgroups were evaluated for antibiotic resistance; five (16.1%), two (6.5%), and three (9.7%) participants showed CLA, MET, and dual resistance in culture-based susceptibility test. Compared with culture-based MIC test, the accuracy of DPO-based multiplex PCR in determining CLA resistance was 90.3%, while the accuracy of survey in determining MET resistance was only 77.4%.

CONCLUSION

A tailored therapy based on DPO-PCR and history of previous antibiotic use is useful in clinical practice and well correlated with culture-based susceptibility test.

Primary antimicrobial resistance rates and prevalence of Helicobacter pylori infection in the north of Spain. A 13-year retrospective study

OBJECTIVE

Helicobacter pylori resistance to antimicrobial agents is on the rise and it is thus imperative to be aware of local resistance rates. The main objective of the present study was to describe the evolution of primary antimicrobial resistance in H. pylori, analysing its antibiotic susceptibility over a 13-year period in a region of northern Spain, as well as host-related factors.

PATIENTS AND METHODS

Between 2004 and 2016 a total of 3426 patients who met the H. pylori eradication criteria underwent gastroscopy. The gastric biopsies were processed and those testing positive for H. pylori were identified and tested for clarithromycin, metronidazole and levofloxacin susceptibility using E-test.

RESULTS

H. pylori was isolated in 1604 (47%) patients, ranging from 63% (133/212) in 2004 to 39% (137/347) in 2016. Primary resistances to clarithromycin, metronidazole and levofloxacin were on average 19% (278/1116), 40% (572/865) and 17% (137/669), respectively. Clarithromycin resistance was 24% (167/686) in females and 15% (11/753) in males (p=0.0002); metronidazole resistance was 29% (72/246) in patients over 70 years compared to 42% (499/1190) in younger patients (p=0.0396); levofloxacin resistance increased with age, being 13% (57/439) in patients ≤55 years, 19% (46/236) for those between 56 and 70, and 26% (34/130) in patients >70 years (p=0.0087).

DISCUSSION

A decline in the prevalence of H. pylori infection was observed over the years, along with relatively high rates of primary resistance to clarithromycin, metronidazole and levofloxacin. Variations in resistance rates were found with sex and age.

Comparison of Levofloxacin-Based, 10-day Sequential Therapy with 14-day Quadruple Therapy for Helicobacter Pylori Eradication: A Randomized Clinical Trial

BACKGROUND

Considering the importance of Helicobacter pylori (H. pylori) eradication, this clinical trial was designed to prospectively evaluate the efficacy of levofloxacin-based, sequential therapy in comparison with quadruple therapy for eradicating H. pylori.

METHODS

Overall 156 patients with dyspepsia and H. pylori infection were included in this study and were randomly allocated to either 10-day sequential therapy group (group A) to receive pantoprazole (40 mg twice daily), amoxicillin (1 gr twice daily), levofloxacin (500 mg twice daily), and tinidazole (500 mg twice daily) (PALT) or 14-day quadruple therapy group (group B) to receive pantoprazole, clarithromycin, bismuth subcitrate, and amoxicillin (PABC). At the end of the study the eradication rate in each group was assessed by urea breath test (UBT).

RESULTS

Age range of the participants was 18-65 years (average 36.9 years) and 50% of them (78 patients) were men. 78 patients were allocated to group A and 78 patients to groupe B. After antibiotic therapy, all the patients received acid suppression therapy with Proton Pump Inhibitor (PPI) for 4 weeks and then the eradication rate was confirmed by UBT (Heli FAN plus 13C, Germany). Before performing UBT, all the participants were requested to halt consumption of PPI for at least 1 week. During the treatment there was not any major complication but in group A (sequential therapy), two patients complained of minor complications including musculoskeletal pain. None of the patients in group B had any complaint or side effect. The rate of H. pylori eradication in group A was 78.2% (61 patients) while this rate in group B was 83.3% (65 patients) with no significant difference between the two groups (p = 0.42). In subgroup analysis, the rate of eradication among men in group A and B were 76.9% and 89.7%, respectively (p = 0.22) while the eradication rate among women were 79.4% and 76.9%, respectively (p = 1.00).

CONCLUSION

It seems that levofloxacin base sequential therapy does not have any advantage in comparison with quadruple regimen and until finding any more effective short course therapy for H. Pylori eradication; we encourage quadruple regimen to be used as the first line therapy.

Current Status of the Third-Line Helicobacter pylori Eradication

Antibiotic resistance is growing worldwide, and patients who have failed consecutive 1st- and 2nd-line H. pylori eradication regimens are increasing. Therefore, the role of the bacterial culture with antibiotic susceptibility testing and molecular susceptibility testing is important for avoiding the use of ineffective antibiotics. However, antibiotic susceptibility testing-guided treatment does not necessarily guarantee successful eradication, and there have been mixed results for the effectiveness of a 3rd-line rescue therapy. Therefore, providing patients with pretreatment medication instructions and education is important. It is also crucial to determine the reason of the eradication failure, including host-related factors (poor compliance to eradication regimen, smoking, and cytochrome P450 2C19 genetic polymorphism) or treatment-related factors (inadequate dosage or duration of therapy and gastric acidity), as such factors can be modified for a tailored therapy. Although the indications for H. pylori eradication have widened, patients at a high risk of gastric cancer can gain definitive benefits with a 3rd-line or even 4th-line therapy.

Are the view of Helicobacter pylori colonized in the oral cavity an illusion?

Urea breath test (UBT), as a leading preferred non-invasive diagnostic technology, but may not be able to detect oral H. pylori. With negative results of UBT, the patient may have an oral infection. On the basis of the fact of success, eradication rate may increase by 21% in the 95% Cl range after the elimination of oral H. pylori, the author believes oral H. pylori does exist and the oral cavity is the second colonized site aside its primary site of the stomach. H. pylori migrated out of Africa along with its human host circa 60 000 years ago; they are not lives in stomach only. In this review article, evidence established in recent years studies with use more appropriate technology had been listed and discussed. The author considers the oral cavity is a black hole for H. pylori infection that significant effective on gastroenterology and another medical field. The role of the oral cavity as the source of H. pylori infection is so controvert in past years. It seems like a human being having a second-time face to discover H. pylori in the history.

Efficacy and tolerability of culture-guided treatment for Helicobacter pylori infection

OBJECTIVE

The aim of this study was to evaluate the efficacy/tolerability of a culture-guided approach in the eradication of Helicobacter pylori and identify factors associated with antibiotic resistance/treatment failure.

PATIENTS AND METHODS

This retrospective single-center study included patients who underwent culture-guided treatment for H. pylori infection, after two ineffective eradication attempts, between October 2012 and December 2016. We assessed the following demographic and clinical data of the patients: sex, age, BMI, alcohol and tobacco consumption, history of dyspepsia, peptic ulceration and first-degree relatives with gastric cancer, antibiotic susceptibility results, treatment composition, tolerability, and success. The treatment success was confirmed by a monoclonal stool antigen test.

RESULTS

Culture-guided treatment was performed in 42 patients (57% women, mean age±SD: 48.9±11.4 years). The rates of antibiotic resistance were as follows: clarithromycin 86%, metronidazole 67%; levofloxacin 52%, tetracycline 2%, and amoxicillin and rifampicin 0%. Double resistance to clarithromycin and metronidazole was found in 59.5% of the patients. Most patients showed resistance to less than three antibiotics, but 31% were resistant to three or more. Intention-to-treat and per-protocol eradication rates were 59.5 and 61.5%. Adverse events occurred in 15 (35.7%) patients, but only two (4.8%) patients did not complete treatment because of adverse events. Only age more than 50 years was associated with resistance to three or more antibiotics. Having a first-degree relative with gastric cancer was associated with treatment failure and having a BMI of at least 25 kg/m protected from failure.

CONCLUSION

Third-line culture-guided treatment often fails to eradicate H. pylori infection. We need to find factors other than in-vitro antibiotic resistance to explain these suboptimal results.

In situ targeted MRI detection of Helicobacter pylori with stable magnetic graphitic nanocapsules

Helicobacter pylori infection is implicated in the aetiology of many diseases. Despite numerous studies, a painless, fast and direct method for the in situ detection of H. pylori remains a challenge, mainly due to the strong acidic/enzymatic environment of the gastric mucosa. Herein, we report the use of stable magnetic graphitic nanocapsules (MGNs), for in situ targeted magnetic resonance imaging (MRI) detection of H. pylori. Several layers of graphene as the shell effectively protect the magnetic core from corrosion while retaining the superior contrast effect for MRI in the gastric environment. Boronic-polyethylene glycol molecules were synthesized and modified on the MGN surface for targeted MRI detection. In a mouse model of H. pylori-induced infection, H. pylori was specifically detected through both T₂-weighted MR imaging and Raman gastric mucosa imaging using functionalized MGNs. These results indicated that enhancement of MRI using MGNs may be a promising diagnostic and bioimaging platform for very harsh conditions.

Importance of antimicrobial susceptibility testing for the management of eradication in Helicobacter pylori infection

The management of Helicobacter pylori (H. pylori) infection treatment differs from the common treatment protocol for other infectious diseases. Because culture- or molecular-guided approaches face several practical issues, such as the invasive procedures required to obtain gastric biopsy specimens and the lack of availability of routine laboratory testing in some places, H. pylori treatment includes the administration of two or three empirically selected antibiotics combined with a proton pump inhibitor rather than evidence-based eradication treatment. The efficacy of empirical therapy is decreasing, mostly due to increasing multiple resistance. Multiresistance to levofloxacin, clarithromycin, and metronidazole, which are commonly used in empirical treatments, appears to have increased in many countries. Mutations play a primary role in the antimicrobial resistance of H. pylori, but many different mechanisms can be involved in the development of antibiotic resistance. Determining and understanding these possible mechanisms might allow the development of new methods for the detection of H. pylori and the determination of antimicrobial resistance. A treatment based on the detection of antimicrobial resistance is usually more effective than empirical treatment. Nevertheless, such an approach before treatment is still not recommended in the Maastricht guidelines due to the difficulty associated with the routine application of available culture- or molecular-based susceptibility tests, which are usually administered in cases of treatment failure. The management of first and rescue treatments requires further research due to the steadily increase in antimicrobial resistance.

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.

Characteristics and Risk Factors of Helicobacter pylori Associated Gastritis: A Prospective Cross-Sectional Study in Northeast Thailand

Background and Aim. Risk factors for Helicobacter pylori infection are genetic susceptibility and poor living conditions. This study aimed to investigate the Mdm2 gene, clarithromycin resistance, and possible risk factors for Helicobacter pylori infection. Methods. Risk factors and clinical characteristics were analyzed, including patient demographic data, patient income, personal history, possible source of transmission, patient symptoms, endoscopic findings, patterns of clarithromycin resistance, and patterns of Mdm2 SNIP309. Results. Ingestion of pickled fish (OR = 11.27, 95% CI = 4.31-29.45, p < 0.0001), salt crab (OR = 8.83, 95% CI = 1.99-39.14, p < 0.001), and Papaya salad (OR = 8.73, 95% CI = 4.54-16.79, p < 0.01). The prevalence of clarithromycin resistance was 56% (wild type, A2143/2142A, is 23.8%; mutation, A2143/2142CG, is 35.7%; wild type + mutation is 40.5%). The genetic polymorphisms of Mdm2 SNIP309 were SNIP309 T/T homozygous in 78%, SNIP309 G/T heterozygous in 19%, and SNIP309 G/G homozygous in 3%. Conclusion. Pickled fish, salt crab, and Papaya salad are positive risk factors. There was high prevalence of clarithromycin resistance. The Mdm2 SNIP309 G/G homozygous genotype might be a risk factor for gastric cancer and the fact that it is infrequent in Thailand.

In vitro antimicrobial susceptibility of Helicobacter pylori to nine antibiotics currently used in Central Italy

OBJECTIVE

Helicobacter pylori expresses an increased resistance in respect to antimicrobials currently used in therapy. The aim of this study was to evaluate the antimicrobial profiles of H. pylori isolates to nine conventional antibiotics used in a Central Region (Abruzzo) of Italy.

MATERIALS AND METHODS

Biopsies were taken from antrum and fundus of 112 adult and 3 children with Urea Breath Test positive with dyspeptic symptoms and analyzed for H. pylori culture and antibacterial activity. Antimicrobial susceptibility tests were performed for clarithromycin, metronidazole, levofloxacin, moxifloxacin, ciprofloxacin, tetracycline, amoxicillin, ampicillin, and rifabutin by a modified agar dilution susceptibility test.

RESULTS

Bacterial culture was successful in 100 out of 115 patients. Helicobacter pylori strains were isolated from 98 antrum and 83 fundus samples. The rate of recovery of H. pylori strains was 90.50% (181/200). The percentages of resistance were as follows: clarithromycin 72.44% antrum, 72.28% fundus; metronidazole 34.69% antrum, 42.16% fundus; levofloxacin 42.85% antrum, 53.01% fundus; moxifloxacin 37.35% antrum, 46.57% fundus; ciprofloxacin 39.47% antrum, 44.28% fundus; tetracycline 2.63% antrum, 2.85% fundus; amoxicillin 1.02% antrum, 1.20% fundus; ampicillin 0% antrum and fundus and rifabutin 0% antrum, 1.20% fundus. A total of 35 subjects harbored multi-resistant strains.

CONCLUSIONS

This study underlines the high rate of resistance to clarithromycin, metronidazole and quinolones, which may reflect an overuse of them. Culture and susceptibility test, should be performed to prevent the emergence of multi-resistance and to assess an efficacious regimen.

Comparison of the efficacy of culture-based tailored therapy for Helicobacter pylori eradication with that of the traditional second-line rescue therapy in Korean patients: a prospective single tertiary center study

OBJECTIVE

The effectiveness of Helicobacter pylori therapies has declined with an increase in antibiotic resistance. To overcome this problem, the efficacy of tailored H. pylori eradication therapy based on antimicrobial susceptibility testing was compared with that of empirical second-line rescue regimens.

MATERIAL AND METHODS

Patients who had persistent H. pylori infection after the first eradication were recommended to undergo culture for determining the minimal inhibitory concentration (MIC) via gastroscopy, which increased the cost by 300%. Fourteen-day esomeprazole, tripotassium dicitrate bismuthate, metronidazole and tetracycline (EBMT) therapy or esomeprazole, moxifloxacin and amoxicillin (MEA) therapy was performed according to the results of antibiotic susceptibility testing. In case of refusal to undergo culture, the participants were treated with either 14-day empirical EBMT or MEA regimen for second eradication after explaining the complexity, side effects and costs associated with each regimen. This trial was registered at ClinicalTrials.Gov (NCT 02349685).

RESULTS

In the 219 patients included, the intention to treat (ITT) and per protocol (PP) eradication rates was 75.3% and 79.8% in the 14-day EBMT group (n = 89), 70.8% and 72.4% in the 14-day MEA group (n = 89) and 87.8% and 100.0% in the 14-day tailored therapy group (n = 41), respectively. Based on the PP analysis, the 14-day tailored therapy group showed a significantly higher eradication rate than the 14-day EBMT or MEA group (both p ≤ 0.001).

CONCLUSIONS

Tailored therapy based on H. pylori culture and MIC test could be an option as a second-line eradication regimen in the presence of high level of antimicrobial resistance.

Helicobacter pylori colonization of the oral cavity: A milestone discovery

Over the past several years, the severity of Helicobacter pylori (H. pylori) infections has not significantly diminished. After successful eradication, the annual H. pylori recurrence rate is approximately 13% due to oral H. pylori infection. Established clinical diagnostic techniques do not identify an oral etiologic basis of H. pylori prior to gastric infection. There has been disagreement as to whether oral infection of H. pylori exists or not, with no definite conclusion. In medical practice, negative results with the urea breath test suggest that the stomach infection of H. pylori is cured in these patients. In fact, patients can present negative urea breath test results and yet exhibit H. pylori infection due to oral infection. The present paper provides evidence that H. pylori oral infection is nonetheless present, and the oral cavity represents a secondary site for H. pylori colonization.

Editorial--Avoiding Unethical Helicobacter pylori Clinical Trials: Susceptibility-Based Studies and Probiotics as Adjuvants

As a general rule, any clinical study where the result is already known or when the investigator(s) compares an assigned treatment against another assigned treatment known to be ineffective in the study population (e.g., in a population with known clarithromycin resistance) is unethical. As susceptibility-based therapy will always be superior to empiric therapy in any population with a prevalence of antimicrobial resistance >0%, any trial that randomizes susceptibility-based therapy with empiric therapy would be unethical. The journal Helicobacter welcomes susceptibility or culture-guided studies, studies of new therapies, and studies of adjuvants and probiotics. However, the journal will not accept for review any study we judge to be lacking clinical equipoise or which assign subjects to a treatment known to be ineffective, such as a susceptibility-based clinical trial with an empiric therapy comparator. To assist authors, we provide examples and suggestions regarding trial design for comparative studies, for susceptibility-based studies, and for studies testing adjuvants or probiotics.

Prevalence of antibiotic resistance in Helicobacter pylori: A recent literature review

AIM: To review previous studies (the last 6 years) about the Helicobacter pylori (H. pylori) antibiotic resistance in order to evaluate the trend in antibiotic resistance.

METHODS: In this study, the PubMed, MEDLINE, Science Direct, Google Scholar and Scielo manuscripts were reviewed from 2009 to 2014.

RESULTS: On the whole rates of H. pylori antibiotic resistance were 47.22% (30.5%-75.02%) for metronidazole, 19.74% (5.46%-30.8%) for clarithromycin, 18.94% (14.19%-25.28%) for levofloxacin, and 14.67% (2%-40.87%) for amoxicillin, 11.70% (0%-50%) for tetracycline, 11.5% (0%-23%) for furazolidon and 6.75% (1%-12.45%) for rifabutin. The frequency of tetracycline, metronidazole and amoxicillin resistance was higher in Africa, while clarithromycin and levofloxacin resistance was higher in North America and Asian, respectively.

CONCLUSION: The most sensitive drug is rifabutin and the lowest sensitive drug is metronidazole in the world. The worldwide H. pylori antibiotic resistance to clarithromycin and levofloxacin has increased during the last 6 years. The present systematic review show alarming results and a novel plan is needed for eradication therapy of H. pylori infections.