Helicobacter pylori resistance to metronidazole and clarithromycin in Ireland

Helicobacter pylori: High dose amoxicillin does not improve primary or secondary eradication rates in an Irish cohort

BACKGROUND

Helicobacter pylori (H. pylori) eradication rates have fallen globally, likely in large part due to increasing antibiotic resistance to traditional therapy. In areas of high clarithromycin and metronidazole resistance such as ours, Maastricht VI guidelines suggest high dose amoxicillin dual therapy (HDADT) can be considered, subject to evidence for local efficacy. In this study we assess efficacy of HDADT therapy for H. pylori eradication in an Irish cohort.

AIM

To assess the efficacy of HDADT therapy for H. pylori eradication in an Irish cohort as both first line, and subsequent therapy for patients diagnosed with H. pylori.

METHODS

All patients testing positive for H. pylori in a tertiary centre were treated prospectively with HDADT (amoxicillin 1 g tid and esomeprazole 40 mg bid × 14 d) over a period of 8 months. Eradication was confirmed with Urea Breath Test at least 4 wk after cessation of therapy. A delta-over-baseline > 4% was considered positive. Patient demographics and treatment outcomes were recorded, analysed and controlled for basic demographics and prior H. pylori treatment.

RESULTS

One hundred and ninety-eight patients were identified with H. pylori infection, 10 patients were excluded due to penicillin allergy and 38 patients refused follow up testing. In all 139 were included in the analysis, 55% (n = 76) were female, mean age was 46.6 years. Overall, 93 (67%) of patients were treatment-naïve and 46 (33%) had received at least one previous course of treatment. The groups were statistically similar. Self-reported compliance with HDADT was 97%, mild side-effects occurred in 7%. There were no serious adverse drug reactions. Overall the eradication rate for our cohort was 56% (78/139). Eradication rates were worse for those with previous treatment [43% (20/46) vs 62% (58/93), P = 0.0458, odds ratio = 2.15]. Age and Gender had no effect on eradication status.

CONCLUSION

Overall eradication rates with HDADT were disappointing. Despite being a simple and possibly better tolerated regime, these results do not support its routine use in a high dual resistance country. Further investigation of other regimens to achieve the > 90% eradication target is needed.

Forty years of Helicobacter pylori infection and changes in findings at esophagogastroduodenoscopy

BACKGROUND

It is 40 years since the discovery of Helicobacter pylori infection. Over that time major changes have occurred in esophagogastroduodenoscopy (EGD) findings. The aim of this review is to describe these changes, and the important role H. pylori infection has played in their evolution.

METHODS

References were identified through searches of PubMed using the search terms-endoscopy time trends, peptic ulcer disease, gastroesophageal reflux disease, upper gastrointestinal cancer, gastric polyps, H. pylori, eosinophilic gastrointestinal disorders, and celiac disease, from 1970 through December 2021.

RESULTS

The prevalence of H. pylori infection has fallen and consequently, H. pylori-positive peptic ulcer disease has become rare. Gastroesophageal reflux disease is now the commonest disorder diagnosed at EGD, and Barrett's esophagus has increased in parallel. Cancer of the distal stomach has fallen while esophageal adenocarcinoma and reflux-related cardia cancer have risen. Gastric polyps have changed from hyperplastic and adenomas to sporadic fundic gland polyps. Antimicrobial resistance has made H. pylori infection more difficult to eradicate. Eosinophilic gastrointestinal disorders, particularly eosinophilic esophagitis, have emerged as important new allergic disorders. Celiac disease has changed and increased.

CONCLUSIONS

EGD findings appear to have changed from features suggesting a H. pylori-positive "phenotype" 40 years ago to a H. pylori-negative "phenotype" today. These changes have major implications for the management of gastrointestinal disorders.

High incidence of antibiotic resistance amongst isolates of Helicobacter pylori collected in Nottingham, UK, between 2001 and 2018

Introduction. Helicobacter pylori is the leading cause of peptic ulcers and gastric cancer. The most common treatment regimens use combinations of two or three antibiotics and a proton pump inhibitor (PPI) to suppress stomach acid. The World Health Organization designated clarithromycin-resistant H. pylori as a high priority pathogen for drug development, due to increasing antibiotic resistance globally.Hypothesis/Gap Statement. There is no routine surveillance of H. pylori primary antimicrobial sensitivities in the UK, and published data are lacking.Aim. This study aimed to characterize antimicrobial sensitivities of isolates collected in Nottingham, UK, between 2001 and 2018.Methodology. Gastric biopsy samples were collected, with informed written consent and ethics approval, from 162 patients attending the Queen's Medical Centre in Nottingham for an upper GI tract endoscopy. Antibiotic sensitivity was assessed using E-Tests and a more cost-effective disc diffusion test.Results. The clarithromycin, amoxicillin and levofloxacin disc diffusion tests provided identical results to E-Tests on a subset of 30 isolates. Disparities were observed in the metronidazole test results, however. In total, 241 isolates from 162 patients were tested using at least one method. Of all isolates, 28 % were resistant to clarithromycin, 62 % to metronidazole and 3 % to amoxicillin, which are used in first-line therapies. For those antibiotics used in second- and third-line therapies, 4 % were resistant to levofloxacin and none of the isolates were resistant to tetracycline. Resistance to more than one antibiotic was found in 27 % of isolates. The frequency of patients with a clarithromycin-resistant strain increased dramatically over time: from 16 % between 2001 and 2005 to 40 % between 2011 and 2018 (P=0.011). For the same time periods, there was also an increase in those with a metronidazole-resistant strain (from 58 to 78 %; P=0.05). The frequencies of clarithromycin and metronidazole resistance were higher in isolates from patients who had previously received eradication therapy, compared to those who had not (40 % versus 77 %, and 80 % versus 92 %, respectively). Of 79 pairs of isolates from the antrum and corpus regions of the same patient's stomach, only six had differences in their antimicrobial susceptibility profiles.Conclusion. Although there was high and increasing resistance to clarithromycin and metronidazole, there was no resistance to tetracycline and the frequencies of amoxicillin and levofloxacin resistance were very low.

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.

Microbial nitroreductases: A versatile tool for biomedical and environmental applications

Nitroreductases, enzymes found mostly in bacteria and also in few eukaryotes, use nicotinamide adenine dinucleotide (NADH) or nicotinamide adenine dinucleotide phosphate (NADPH) as a cofactor for their activity and metabolize an enormous list of a diverse nitro group-containing compounds. Nitroreductases that are capable of metabolizing nitroaromatic and nitro heterocyclic compounds have drawn great attention in recent years owing to their biotechnological, biomedical, environmental, and human impact. These enzymes attracted medicinal chemists and pharmacologists because of their prodrug selectivity for activation/reduction of nitro compounds that wipe out pathogens/cancer cells, leaving the host/normal cells unharmed. It is applied in diverse fields of study like prodrug activation in treating cancer and leishmaniasis, designing fluorescent probes for hypoxia detection, cell imaging, ablation of specific cell types, biodegradation of nitro-pollutants, and interpretation of mutagenicity of nitro compounds. Keeping in view the immense prospects of these enzymes and a large number of research contributions in this area, the present review encompasses the enzymatic reaction mechanism, their role in antibiotic resistance, hypoxia sensing, cell imaging, cancer therapy, reduction of recalcitrant nitro chemicals, enzyme variants, and their specificity to substrates, reaction products, and their applications.

Sociodemographic characteristics and clinical risk factors of Helicobacter pylori infection and antibiotic resistance in the Eastern Black Sea region of Turkey

BACKGROUND/AIMS

The aim of this study was to assess the clinical and sociodemographic risk factors of Helicobacter pylori infection and antibiotic resistance in the eastern Black Sea region of Turkey.

MATERIALS AND METHODS

In total, 344 patients with dyspeptic symptoms who completed an extended questionnaire were enrolled in the study. Diagnosis of H. pylori infection was made by rapid urease test, histopathological investigation, and culture. Susceptibility of H. pylori strains was assessed by agar dilution (amoxicillin, tetracycline, metronidazole, levofloxacin) and E-test (clarithromycin) methods.

RESULTS

The H. pylori positivity rate was 40.4% (139/344). Logistic regression analysis indicated that age and the presence of duodenal ulcer were independent risk factors associated with H. pylori positivity (odds ratio (OR): 0.96, 95% CI: 0.93-0.99, p=0.013; OR: 5.42, 95% CI: 1.96-14.98, p=0.001, respectively). Of 104 H. pylori-positive cultures, 43 strains (41%) were susceptible to all antibiotics, whereas 61 (59%) were resistant to at least one antibiotic. H. pylori resistance rates were 34% for levofloxacin, 31.1% for metronidazole, 28.2% for clarithromycin, 2.9% for amoxicillin, and 1% for tetracycline. Logistic regression analysis indicated that previous use of clarithromycin was the only independent risk factor for H. pylori resistance (OR: 6.25, 95% CI: 1.59-24.52, p=0.009).

CONCLUSION

An understanding of the risk factors for H. pylori positivity and antibiotic resistance in an extended anamnesis may affect treatment choice and facilitate H. pylori eradication. In regions where antibiotic resistance rates are elevated, performing antibiotic susceptibility tests may lead to effective eradication treatment.

Management of Antibiotic-Resistant Helicobacter pylori Infection: Perspectives from Vietnam

Antibiotic resistance is the most important factor leading to the failure of eradication regimens. This review focuses on the prevalence of Helicobacter pylori primary and secondary resistance to clarithromycin, metronidazole, amoxicillin, levofloxacin, tetracycline, and multidrug in Vietnam. We searched the PubMed, EMBASE, Vietnamese National Knowledge Infrastructure, and Vietnamese Biomedical databases from January 2000 to December 2016. The search terms included the following: H. pylori infection, antibiotic (including clarithromycin, metronidazole, amoxicillin, levofloxacin, tetracycline, and multidrug) resistance in Vietnam. The data were summarized in an extraction table and analyzed manually. Finally, Excel 2007 software was used to create charts. Ten studies (three studies in English and seven in Vietnamese) were included in this review. A total of 308, 412, 523, 408, 399, and 268 H. pylori strains were included in this review to evaluate the prevalence of H. pylori primary resistance to amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and multidrug resistance, respectively. Overall, the primary resistance rates of amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and multidrug resistance were 15.0%, 34.1%, 69.4%, 27.9%, 17.9% and 48.8%, respectively. Secondary resistance rates of amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and multidrug resistance were 9.5%, 74.9%, 61.5%, 45.7%, 23.5% and 62.3%, respectively. In Vietnam, primary and secondary resistance to H. pylori is increasing over time and affects the effectiveness of H. pylori eradication.

Antibiotic dispensation rates among participants in community-driven health research projects in Arctic Canada

Background

Community-driven projects that aim to address public concerns about health risks from H. pylori infection in Indigenous Arctic communities (estimated H. pylori prevalence = 64%) show frequent failure of treatment to eliminate the bacterium. Among project participants, treatment effectiveness is reduced by antibiotic resistance of infecting H. pylori strains, which in turn, is associated with frequent exposure to antibiotics used to treat other infections. This analysis compares antibiotic dispensation rates in Canadian Arctic communities to rates in urban and rural populations in Alberta, a southern Canadian province.

Methods

Project staff collected antibiotic exposure histories for 297 participants enrolled during 2007–2012 in Aklavik, Tuktoyaktuk, and Fort McPherson in the Northwest Territories, and Old Crow, Yukon. Medical chart reviews collected data on systemic antibiotic dispensations for the 5-year period before enrolment for each participant. Antibiotic dispensation data for urban Edmonton, Alberta (average population ~ 860,000) and rural northern Alberta (average population ~ 450,000) during 2010–2013 were obtained from the Alberta Government Interactive Health Data Application.

Results

Antibiotic dispensation rates, estimated as dispensations/person-years (95% confidence interval) were: in Arctic communities, 0.89 (0.84, 0.94); in Edmonton, 0.55 (0.55, 0.56); in rural northern Alberta, 0.63 (0.62, 0.63). Antibiotic dispensation rates were higher in women and older age groups in all regions. In all regions, the highest dispensation rates occurred for β-lactam and macrolide antibiotic classes.

Conclusions

These results show more frequent antibiotic dispensation in Arctic communities relative to an urban and rural southern Canadian population.

Molecular diagnosis of Helicobacter pylori antibiotic resistance in the Taif region, Saudi Arabia

Success in eradication of Helicobacter pylori is declining globally because H. pylori has developed resistance against most of the antibiotics proposed for eradication regimens, mainly through point mutations. The present study included 200 patients with dyspepsia attending Taif Hospital. Gastric biopsies were obtained during gastroscopy and subjected to rapid urease testing. Molecular methods were used to confirm diagnoses of H. pylori infection and to identify resistance gene variants of four antibiotics; namely, clarithromycin, metronidazole, fluoroquinolones and tetracycline (23S rRNA, gyrA, rdxA and 16S rRNA respectively). Of all investigated patients, Molecular diagnoses were made in 143 of all investigated patients; thus, the prevalence was .5%. The overall rate of resistance to clarithromycin among the H. pylori-positive patients was high (39.9%) and the rate of resistance significantly greater (48.2%) among the secondary resistance group, secondary resistance being defined as resistance as a result of previous exposure to the relevant antibiotic. The rate of resistance to fluoroquinolones was considered moderate; the difference in rate of resistance between the primary and secondary resistance groups (8.4% and 9.5%, respectively) was not significant Also, there was a low prevalence of both primary and the secondary tetracycline resistance in the study cohort. In contrast, the prevalence of metronidazole resistance was considered high with no significant difference between the two resistance groups. H. pylori showed an increased prevalence of resistance to all four of the commonly used therapeutic agents. Thus, eradication therapy should be based on the regional results of susceptibility testing. Moreover, treatment tailored according to individually determined H. pylori susceptibility may be a reasonable future goal.

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.

Can bacterial virulence factors predict antibiotic resistant Helicobacter pylori infection?

AIM

To evaluate the association between virulence factor status and antibiotic resistance in Helicobacter pylori (H. pylori)-infected patients in Ireland.

METHODS

DNA was extracted from antral and corpus biopsies obtained from 165 H. pylori-infected patients. Genotyping for clarithromycin and fluoroquinolone-mediating mutations was performed using the Genotype HelicoDR assay. cagA and vacA genotypes were investigated using PCR.

RESULTS

Primary, secondary and overall resistance rates for clarithromycin were 50.5% (n = 53/105), 78.3% (n = 47/60) and 60.6% (n = 100/165), respectively. Primary, secondary and overall resistance rates for fluoroquinolones were 15.2% (n = 16/105) and 28.3% (n = 17/60) and 20% (n = 33/165), respectively. Resistance to both antibiotics was 12.4% (n = 13/105) in treatment-naïve patients, 25% (n = 15/60) in those previously treated and 17% (n = 28/165) overall. A cagA-positive genotype was detected in 22.4% (n = 37/165) of patient samples. The dominant vacA genotype was S1/M2 at 44.8% (n = 74/165), followed by S2/M2 at 26.7% (n = 44/165), S1/M1 at 23.6% (n = 39/165) and S2/M1 at 4.8% (n = 8/165). Primary clarithromycin resistance was significantly lower in cagA-positive strains than in cagA-negative strains [32% (n = 8/25) vs 56.3% (n = 45/80) P = 0.03]. Similarly, in patients infected with more virulent H. pylori strains bearing the vacA s1 genotype, primary clarithromycin resistance was significantly lower than in those infected with less virulent strains bearing the vacA s2 genotype, [41% (n = 32/78) vs 77.8% (n = 21/27) P = 0.0001]. No statistically significant association was found between primary fluoroquinolone resistance and virulence factor status.

CONCLUSION

Genotypic H. pylori clarithromycin resistance is high and cagA-negative strains are dominant in our population. Less virulent (cagA-negative and vacA S2-containing) strains of H. pylori are associated with primary clarithromycin resistance.

Primary antibiotic resistance of Helicobacter pylori strains among adults and children in a tertiary referral centre in Lithuania

The study evaluated primary antibiotic resistance of Helicobacter pylori within the period 2013-2015 and trends of antibiotic consumption over the last decade in Lithuania; 242 adults and 55 children were included in the study. E-tests were performed for amoxicillin, metronidazole, clarithromycin, ciprofloxacin, rifampicin and tetracycline. The presence of H. pylori and clarithromycin resistance was additionally tested by PCR. Helicobacter pylori culture was positive in 67 of 242 (28%) adult and in 12 of 55 (21.8%) children samples. Resistance rates among adults by E-tests were as follows: metronidazole - 32.8% (95% confidence interval (CI): 22.7-44.7%), ciprofloxacin - 7.5% (95% CI: 3.2-16.3%), rifampicin - 7.5% (95% CI: 3.2-16.3%), amoxicillin - 0%, whereas resistance rates in children were as follows: metronidazole - 25% (95% CI: 8.9-53.2%), rifampicin - 8.3% (CI: 1.5-35.4%), amoxicillin and ciprofloxacin - 0%. Accumulated clarithromycin resistance rates by E-tests and PCR were 8.2% (95% CI: 4.1-16.0%) in adults and 17.7% (95% CI: 6.2-41.0%) in children. Total use of macrolides and lincosamides in Lithuania increased from 1.26 to 1.86 defined daily dose (DDD)/1000 inhabitants/day among adults, while it has doubled from 1.10 to 2.22 DDD/1000/children/day in children within 2003-2015. There are no significant changes in the susceptibility of H. pylori to the most widely used antibiotics in adults over the last years in Lithuania; however, clarithromycin resistance among children exceeds 15% and mandates further larger-scale studies in paediatric population.

High primary antibiotic resistance of Helicobacter Pylori strains isolated from dyspeptic patients: A prevalence cross-sectional study in Spain

BACKGROUND

The rate of H. pylori resistance to different antibiotics is increasing and determines the selection of eradication therapy. The aim of this study was to determine the resistance patterns of H. pylori strains in our area.

METHODS

Biopsies from gastric corpus for microbiological culture and antibiotic resistance were obtained in patients undergoing upper gastrointestinal endoscopy for dyspepsia. Selective Agar Pylori for isolation of the bacteria and Agar Mueller-Hinton supplemented with blood to test the sensitivity to antibiotics were used. Presence of H. pylori was confirmed using direct observation with phase-contrast microscopy and/or smears stained with acridine orange. In vitro bacterial susceptibility to amoxicillin, clarithromycin, rifampicin, tetracycline, metronidazole, and levofloxacin was tested using diffusion MIC test strips. Minimum inhibitory concentration values were determined based on the 6th version of the EUCAST (European Committee on Antimicrobial Susceptibility Testing) Clinical Breakpoint (2016).

RESULTS

Two hundred and seventeen patients were included (58.1% female, median age 64 years, range 25-92). H. pylori was identified in 108 patients (49.8%); culture and antibiogram were completed in 77 of them (71.3% of H. pylori-positive patients). The resistance rates were as follows: levofloxacin 38.7%, rifampicin 33.3%, metronidazole 27% and clarithromycin 22.4%. No case of amoxicillin or tetracycline resistance was identified. Dual clarithromycin-metronidazole resistance was observed in 10% of strains, whereas multiple drug-resistant was observed in 14.2%.

CONCLUSIONS

Resistance rate of H. pylori to antibiotics is high in the northwest of Spain. The high resistance to levofloxacin and clarithromycin advises against their wide empirical use of these antibiotics in eradication regimens.

Influence of Dietary Factors on Helicobacter pylori and CagA Seroprevalence in Bulgaria

The aim of this study was to assess the association between some dietary factors and prevalence of H. pylori infection or strain virulence in 294 adult asymptomatic blood donors. Methods. Seroprevalence was evaluated using ELISA. Logistic regression was used. Results. Anti-H. pylori IgG prevalence was 72.4%, and CagA IgG seroprevalence was 49.3%. In the multivariate analyses, the frequent (>5 days per week) honey consumption was associated with both reduced H. pylori seroprevalence OR, 0.68 with 95% confidence interval (CI), 0.473-0.967 and reduced CagA IgG seroprevalence OR, 0.65 with 95% CI, 0.486-0859. Frequent (>5 days per week) yoghurt consumption also was associated with lower H. pylori virulence of the strains (CagA IgG OR, 0.56 with 95% CI, 0.341-0.921). Smoking and consumption of the other dietary factors resulted in no significant differences in the prevalence of H. pylori IgG and CagA IgG within the subject groups. Conclusion. To the best of our knowledge, this is the first report revealing reverse associations between honey or yoghurt consumption and CagA IgG prevalence as well as between frequent honey consumption and lower prevalence of the H. pylori infection. Regular honey and yoghurt consumption can be of value as a supplement in the control of H. pylori therapy.

The Irish Helicobacter pylori Working Group consensus for the diagnosis and treatment of H. pylori infection in adult patients in Ireland

BACKGROUND

Irish eradication rates for Helicobacter pylori are decreasing and there is an increase in the prevalence of antibiotic-resistant bacteria. These trends call into question current management strategies.

OBJECTIVE

To establish an Irish Helicobacter pylori Working Group (IHPWG) to assess, revise and tailor current available recommendations.

METHODS

Experts in the areas of gastroenterology and microbiology were invited to join the IHPWG. Questions of relevance to diagnosis, first-line and rescue therapy were developed using the PICO system. A literature search was performed. The 'Grading of Recommendations Assessment, Development and Evaluation' approach was then used to rate the quality of available evidence and grade the resulting recommendations.

RESULTS

Key resultant IHPWG statements (S), the strength of recommendation and quality of evidence include S8: standard triple therapy for 7 days' duration can no longer be recommended (strong and moderate). S9: 14 days of clarithromycin-based triple therapy with a high-dose proton pump inhibitor (PPI) is recommended as first-line therapy. Bismuth quadruple therapy for 14 days is an alternative if available (strong and moderate). S12: second-line therapy depends on the first-line treatment and should not be the same treatment. The options are (a) 14 days of levofloxacin-based therapy with high-dose PPI, (b) 14 days of clarithromycin-based triple therapy with high-dose PPI or (c) bismuth quadruple therapy for 14 days (strong and moderate). S13: culture and antimicrobial susceptibility testing should be performed following two treatment failures (weak and low/very low).

CONCLUSION

These recommendations are intended to provide the most relevant current best-practice guidelines for the management of H. pylori infection in adults in Ireland.

A randomized-controlled study to compare the efficacy of sequential therapy with standard triple therapy for Helicobacter pylori eradication in an Irish population

INTRODUCTION

Eradication rates for the standard first-line triple therapy for Helicobacter pylori infection have decreased in recent years. Sequential therapy has been suggested as an alternative. The efficacy of sequential therapy has not been assessed to date in an Irish population.

OBJECTIVE

The aim of this study was to compare the efficacy of standard triple therapy with sequential therapy for H. pylori eradication.

PATIENTS AND METHODS

A prospective randomized-controlled study was carried out. Treatment-naive H. pylori-infected patients were randomized to receive either standard triple therapy or sequential therapy.

RESULTS

In all, 87 eligible patients were recruited into the study, one of whom dropped out. Fifty-one per cent (N=44) patients received standard triple therapy and 49% (N=42) patients received sequential therapy. The eradication efficacy by intention-to-treat analysis was 56.8% [N=25/44; 95% confidence interval (CI) 42.2-71.4%] for standard triple therapy and 69% (N=29/42; 95% CI 55.0-83.0%) for sequential therapy. The eradication rates by per-protocol analysis for standard triple therapy and sequential therapy were 61% (N=25/41; 95% CI 46.1-76.0%) and 69% (N=29/42; 95% CI 55.0-83.0%), respectively. The differences in eradication rates for each treatment by either intention-to-treat or per-protocol analysis were not statistically significant (P=0.24 and 0.44, respectively). In addition, incidence in adverse events was not significantly different between the study groups. The most common adverse event reported was mild nausea at 15% (95% CI 7.5-22.6%).

CONCLUSION

Sequential therapy had a nonstatistically significant advantage over standard triple therapy in our patient cohort. However, eradication rates for both standard triple therapy and sequential therapy were suboptimal. Further studies are required to identify potential alternatives to standard first-line triple therapy.

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.

Antimicrobial susceptibility testing for Helicobacter pylori in times of increasing antibiotic resistance

The gram-negative bacterium Helicobacter pylori (H. pylori) causes chronic gastritis, gastric and duodenal ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Treatment is recommended in all symptomatic patients. The current treatment options for H. pylori infection are outlined in this review in light of the recent challenges in eradication success, largely due to the rapid emergence of antibiotic resistant strains of H. pylori. Antibiotic resistance is a constantly evolving process and numerous studies have shown that the prevalence of H. pylori antibiotic resistance varies significantly from country to country, and even between regions within the same country. In addition, recent data has shown that previous antibiotic use is associated with harbouring antibiotic resistant H. pylori. Local surveillance of antibiotic resistance is warranted to guide clinicians in their choice of therapy. Antimicrobial resistance is assessed by H. pylori culture and antimicrobial susceptibility testing. Recently developed molecular tests offer an attractive alternative to culture and allow for the rapid molecular genetic identification of H. pylori and resistance-associated mutations directly from biopsy samples or bacterial culture material. Accumulating evidence indicates that surveillance of antimicrobial resistance by susceptibility testing is feasible and necessary to inform clinicians in their choice of therapy for management of H. pylori infection.

In vitro and in vivo activities of HPi1, a selective antimicrobial against Helicobacter pylori

A high-throughput screen (HTS) was performed to identify molecules specifically active against Helicobacter pylori, the causative agent of peptic ulcer and gastric carcinoma. Currently, treatment of H. pylori infection is suboptimal, with failure rates approaching 25%, despite triple therapy with two broad-spectrum antibiotics and a proton pump inhibitor or quadruple therapy with added bismuth. The HTS was performed in 384-well plates, and reduction of the metabolic indicator resazurin was used as a reporter for cell growth. Diverse molecules from commercial sources were identified as hits, and in vitro validations included measurements of MIC and time-dependent killing as well as anaerobic susceptibility testing against a panel of gut microbes. In vivo validation included testing in the mouse model of H. pylori infection. The small molecule HPi1 (3-hydrazinoquinoxaline-2-thiol) had excellent potency, with an MIC of 0.08 to 0.16 μg/ml and good selectivity for H. pylori compared to a panel of commensal bacteria. HPi1 was also effective in a mouse model of H. pylori infection, reducing colony counts to below the limit of detection after oral dosing of 25 mg/kg/day for 3 days. HPi1 is a promising lead in the search for more effective and specific H. pylori therapeutics.

Epidemiology and pattern of antibiotic resistance in Helicobacter pylori: scenario from Saudi Arabia

Helicobacter pylori is recognized as a major cause of gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoma. Infection with this gram-negative microaerophile has been treated using combination of antibiotics and proton pump inhibitors for different gastrointestinal diseases. The most commonly used treatment is triple therapy which consists of administration of a proton pump inhibitor, clarithromycin, and amoxicillin. Many factors contribute to treatment failure, but one of the main reasons is development of bacterial antibiotic resistance. The percent prevalence of antibiotic resistance varies among different countries; it appears to be partly determined by the geographic factors and its ability to undergo frequent homologous recombination. The aim of this paper is to review the prevalence of H. pylori infection, association of clinical outcomes with H. pylori genotypes, and current status of antibiotic resistance in H. pylori in Saudi Arabia. It also discusses the different alternative approaches for the treatment of H. pylori using antibiotics. In addition, association of antibiotic resistance with H. pylori virulent genotypes in Saudi population and its underlying resistance mechanism will also be discussed.

Helicobacter pylori infection in Europe: current perspectives

There is a commonly held perception that Helicobacter pylori related diseases are declining, however these are still associated with a high risk of morbidity and mortality. In recent years worrying themes have emerged such as increasing levels of antibiotic resistance and falling cure rates which illustrate there is no room for complacency with respect to H. pylori. In addition there are many significant issues which have not been elucidated regarding the role played by H. pylori in very serious pathologies such as gastric and esophageal cancer and other more benign disorders common in the developed world such as gastroesophageal reflux disease, functional dyspepsia and perhaps obesity which carry a significant impact both economically and as regards to symptoms. Future guidelines aimed at European practitioners and patients will need to address the questions raised by these issues as well as the more familiar areas such as constituents and duration of therapy.

Helicobacter pylori resistance rates for levofloxacin, tetracycline and rifabutin among Irish isolates at a reference centre

INTRODUCTION

Helicobacter pylori eradication rates using conventional triple therapies are falling, making viable second-line and rescue regimens necessary. Levofloxacin, tetracycline and rifabutin are three efficacious antibiotics for rescue therapy.

AIM

We aimed to assess the resistance rates for H. pylori against these antibiotics in an Irish cohort.

METHODS

Gastric biopsies were collected from 85 patients infected with H. pylori (mean age 46 years) in the Adelaide and Meath Hospital, Dublin in 2008 and 2009. Susceptibility to antibiotics was tested using the Etest. Clinical information was obtained from endoscopy reports and chart review.

RESULTS

50.6 % of patients were females. Mean age was 47 years. Ten had prior attempts at eradication therapy with amoxicillin-clarithromycin-PPI, two had levofloxacin-based second-line therapy. 11.7 % [95 % CI (6.5-20.3 %)] (N = 10) had strains resistant to levofloxacin. There were no strains resistant to rifabutin or tetracycline. Levofloxacin resistance in the under 45 age group was 2.6 % (1/38) compared to 19.1 % (9/47) of above 45 age group (p = 0.02).

DISCUSSION

The levofloxacin rates illustrated in this study are relatively low by European standards and in line with other studies from the United Kingdom and Germany, with younger patients having very low levels of resistance. Levofloxacin, tetracycline and rifabutin are all valid options for H. pylori eradication in Irish patients but the importance of compliance cannot be underestimated.

Identification of two novel immunodominant UreB CD4(+) T cell epitopes in Helicobacter pylori infected subjects

An epitope-based vaccine is a promising option for treating Helicobacter pylori (H. pylori) infection. Epitope mapping is the first step in designing an epitope-based vaccine. A pivotal role of CD4(+) T cells in protection against H. pylori has been accepted, but few Th epitopes have been identified. In this study, two novel UreB CD4(+) T cell epitopes were identified using PBMCs obtained from two H. pylori infected subjects. We determined the restriction molecules by antibody blocking and used various Epstein-Barr virus-transformed B lymphocyte cell lines (BLCLs) with different HLA alleles as APCs to present peptides to CD4(+) T cells. These epitopes were DRB1*1404-restricted UreB(373-385) and DRB1*0803-restricted UreB(438-452). The T cells specific to these epitopes not only recognized autologous DCs loaded with recombinant UreB but also those pulsed with H. pylori whole cell lysates, suggesting that these epitope peptides are naturally processed. These epitopes have important value for designing an effective H. pylori vaccine.

High-dose, ten-day esomeprazole, amoxicillin and metronidazole triple therapy achieves high Helicobacter pylori eradication rates

BACKGROUND

Strong acid inhibition using esomeprazole increases cure rates with triple therapy and 10-day treatments are more effective than 7-day ones. The combination of amoxicillin plus metronidazole at full doses, and using a physiologically-correct schedule three times a day, and has been shown to overcome metronidazole resistance and to achieve good eradication rates.

AIMS

To assess the eradication rate of a new first-line treatment regimen associating strong acid inhibition, amoxicillin and metronidazole and to evaluate tolerance.

METHODS

Patients from eight hospitals were included. Helicobacter pylori status was assessed by at least one of the following: histology, culture, rapid urease test or urea breath test (UBT). Ten-day treatment was prescribed comprising esomeprazole 40 mg twice a day plus amoxicillin 1 g and metronidazol 500 mg both three times a day. Helicobacter pylori cure was assessed by UBT.

RESULTS

A hundred and thirty-six patients were enrolled. Mean age was 52.6 ± 16 years and 59.6% of patients were men. Main indications for treatment were: uninvestigated dyspepsia (13.6%); functional dyspepsia (18.2%); gastric ulcer (21.8%); and duodenal ulcer (39.8%). Helicobacter pylori eradication was achieved in 112 of the 127 patients who returned for follow-up. Eradication rates were 82.4% (95% CI: 74.7-88.1) by intention-to-treat analysis and 88.2% (95% CI: 81.2-92.8) by per protocol. Treatment was well tolerated and no major side effects were reported. Nine patients complained of mild side effects.

CONCLUSIONS

Cure rates of the combination of esomeprazole, amoxicillin and metronidazole are high and the treatment was well tolerated. This pilot study warrants the comparison of this schedule with current standards.

The Optimal First-Line Therapy of Helicobacter pylori Infection in Year 2012

This paper reviews the literature about first-line therapies for H. pylori infection in recent years. First-line therapies are facing a challenge because of increasing treatment failure due to elevated antibiotics resistance. Several new treatment strategies that recently emerged to overcome antibiotic resistance have been surveyed. Alternative first-line therapies include bismuth-containing quadruple therapy, sequential therapy, concomitant therapy, and hybrid therapy. Levofloxacin-based therapy shows impressive efficacy but might be employed as rescue treatment due to rapidly raising resistance. Rifabutin-based therapy is also regarded as a rescue therapy. Several factors including antibiotics resistance, patient compliance, and CYP 2C19 genotypes could influence the outcome. Clinicians should use antibiotics according to local reports. It is recommended that triple therapy should not be used in areas with high clarithromycin resistance or dual clarithromycin and metronidazole resistance.

Antibiotic resistance and cagA gene correlation: A looming crisis of Helicobacter pylori

AIM: To determine antibiotic resistance of Helicobacter pylori (H. pylori) in Pakistan and its correlation with host and pathogen associated factors.

METHODS: A total of 178 strains of H. pylori were isolated from gastric biopsies of dyspeptic patients. Susceptibility patterns against first and second-line antibiotics were determined and trends of resistance were analyzed in relation to the sampling period, gastric conditions and cagA gene carriage. The effect of cagA gene on the acquisition of resistance was investigated by mutant selection assay.

RESULTS: The observations showed that monoresistant strains were prevalent with rates of 89% for metronidazole, 36% for clarithromycin, 37% for amoxicillin, 18.5% for ofloxacin and 12% for tetracycline. Furthermore, clarithromycin resistance was on the rise from 2005 to 2008 (32% vs 38%, P = 0.004) and it is significantly observed in non ulcerative dyspeptic patients compared to gastritis, gastric ulcer and duodenal ulcer cases (53% vs 20%, 18% and 19%, P = 0.000). On the contrary, metronidazole and ofloxacin resistance were more common in gastritis and gastric ulcer cases. Distribution analysis and frequencies of resistant mutants in vitro correlated with the absence of cagA gene with metronidazole and ofloxacin resistance.

CONCLUSION: The study confirms the alarming levels of antibiotic resistance associated with the degree of gastric inflammation and cagA gene carriage in H. pylori strains.

The status of antimicrobial resistance of Helicobacter pylori in Eastern Azerbaijan, Iran: comparative study according to demographics

Helicobacter pylori-associated infections are extremely common in Iran, but few data about antibiotic sensitivity of H. pylori are available for this region. The purpose of this study was to investigate the prevalence of resistance in isolates against commonly used antibiotics in Eastern Azerbaijan, Iran, and the dependence of prevalence on the sex and age of patients. H. pylori isolates were collected by culture from gastric biopsies. Antibiotic susceptibility of isolates was determined by use of the disk agar diffusion test, and the minimum inhibitory concentration of clarithromycin was established by use of the Etest. A total 395 of biopsy specimens were studied; 112 samples of H. pylori were isolated (28.3 %), 55 (49 %) from males and 57 (51 %) from females. The prevalence of resistance to clarithromycin, metronidazole, erythromycin, amoxicillin, ciprofloxacin, rifampin, nitrofurantoin, and tetracycline were 16 (14.3 %), 86 (76.8 %), 29 (26.0 %), 32 (28.6 %), 37 (33.0 %), 32 (28.6 %), 13 (11.6 %), and 21 (18.7 %), respectively. Antimicrobial resistance was not statistically significantly associated with sex or age. Furthermore, the prevalence of resistance to metronidazole was high and that to clarithromycin was reasonable, consistent with reported low success in H. pylori treatment in this area. Therefore, continuous surveillance of antibiotic resistance of H. pylori is essential.

Is Helicobacter pylori antibiotic resistance surveillance needed and how can it be delivered?

BACKGROUND

Most patients are prescribed Helicobacter pylori treatment without culture and antibiotic susceptibility testing, as current guidance recommends that patients with recurrent dyspepsia should be tested for H. pylori using a non-invasive breath or faecal antigen test.

AIMS

To determine the prevalence of H. pylori antibiotic resistance in patients attending endoscopy in England and Wales, and the feasibility of an antibiotic resistance surveillance programme testing.

METHODS

We tested the antibiotic susceptibility of H. pylori isolates from biopsy specimens from 2063 of 7791 (26%) patients attending for endoscopy in Gloucester and Bangor, and 339 biopsy specimens sent to the Helicobacter Reference Unit (HRU) in London. Culture and susceptibility testing was undertaken in line with National and European methods.

RESULTS

Helicobacter pylori were cultured in 6.4% of 2063 patients attending Gloucester and Bangor hospitals. Resistance to amoxicillin, tetracycline and rifampicin/rifabutin was below 3% at all centres. Clarithromycin, metronidazole and quinolone resistance was significantly higher in HRU (68%, 88%, 17%) and Bangor isolates (18%, 43%, 13%) than Gloucester (3%, 22%, 1%). Each previous course of these antibiotics is associated with an increase in the risk of antibiotic resistance to that agent [clarithromycin: RR = 1.5 (P = 0.12); metronidazole RR = 1.6 (P = 0.002); quinolone RR = 1.8 (P = 0.01)].

CONCLUSIONS

Helicobacter pylori infection is now uncommon in dyspeptic patients at endoscopy. A surveillance system is feasible and necessary to inform dyspepsia management guidance. Clinicians should take a thorough antibiotic history before prescribing metronidazole, clarithromycin or levofloxacin for H. pylori.

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.

Effect of Helicobacter pylori eradication therapy on risk of hospitalization for a major ulcer event

STUDY OBJECTIVE

To compare Helicobacter pylori eradication therapy with antisecretory therapy alone on the risk of hospitalization for a major ulcer event.

DESIGN

Retrospective, population-based cohort study.

DATA SOURCE

The 2000-2006 National Health Insurance database in Taiwan.

PATIENTS

A total of 838,176 patients diagnosed with a gastrointestinal ulcer and who filled at least one prescription for antiulcer therapy, either H. pylori eradication therapy (331,364 patients [39.53%]) or antisecretory therapy alone (506,812 patients [60.47%]), between January 1, 2001, and December 31, 2006.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was hospitalization for a major ulcer event, defined as a gastrointestinal ulcer with hemorrhage and/or perforation. Cox proportional hazards models, adjusted for demographic and clinical characteristics, were used to compare the risk of hospitalization for a major ulcer event between the group receiving H. pylori eradication therapy (triple or quadruple combination therapy that includes an antisecretory agent) and the group receiving antisecretory therapy alone (histamine₂-receptor blocker or proton pump inhibitor). The H. pylori eradication therapy group was divided into initial users (combination therapy received immediately after gastrointestinal ulcer diagnosis) and late users (combination therapy received after antisecretory therapy with time lag ≤ 180 days, 181-365 days, or > 365 days from ulcer diagnosis). A secondary analysis was conducted in the three late H. pylori eradication therapy subgroups to determine if risk of hospitalization for major ulcer events differed by timing of receipt of therapy. Compared with the antisecretory therapy alone group, the H. pylori therapy group (initial users) had a significantly decreased risk of hospitalization for major ulcer events (adjusted hazard ratio [AHR] 0.57, 95% confidence interval [CI] 0.54-0.59, p<0.001). However, later use of H. pylori therapy was associated with a higher risk of hospitalization for major ulcer events (time lag 181-365 days, AHR 1.68, 95% CI 1.51-1.86, p<0.001; > 365 days, AHR 1.74, 95% CI 1.67-1.80, p<0.001) compared with those who received H. pylori therapy within 6 months (≤ 180 days) after gastrointestinal ulcers were diagnosed.

CONCLUSION

Helicobacter pylori therapy given within 6 months of a diagnosis of gastrointestinal ulcer was associated with a reduced risk of hospitalization for major ulcer events. Our findings extend the evidence from clinical trials that report the value of H. pylori eradication therapy in reducing ulcer recurrence by documenting the real-world benefit of reducing the risk of hospitalization for major gastrointestinal ulcer events.

Numerous risk factors for Helicobacter pylori antibiotic resistance revealed by extended anamnesis: a Bulgarian study

The aim of this study was to assess risk factors for primary Helicobacter pylori antibiotic resistance by an extended anamnesis. In total, 519 H. pylori strains from untreated symptomatic adults who answered a questionnaire were evaluated. Strain susceptibility was assessed by a breakpoint susceptibility test. Primary resistance rates were 29.5 % for metronidazole, 17.9 % for clarithromycin, 7.3 % for metronidazole+clarithromycin, 4.0 % for tetracycline and 10.8 % for ciprofloxacin. On multivariate analysis, younger (≤65 years) age was an independent predictor for metronidazole resistance. To our knowledge, for the first time, being a member of the health-care profession was revealed as a risk factor for H. pylori resistance to metronidazole and both metronidazole and clarithromycin. Respiratory and urinary tract infections were independent predictors of clarithromycin and ciprofloxacin resistance, respectively. The presence of co-infections was an independent risk factor for clarithromycin, metronidazole and ciprofloxacin resistance. Surprisingly, female sex was the only predictor for tetracycline resistance. The antibiotic resistance rates were not associated with disease type, place of residence, birthplace, educational level, non-steroidal anti-inflammatory drug or proton pump inhibitor use, smoking or dietary factors, such as consumption of coffee, yogurt, green tea, raw garlic, raw onion, honey or meat. There was a trend for higher metronidazole resistance in strains from diabetic patients. In conclusion, the extended anamnesis of H. pylori-positive patients should include data on patient age, sex, whether they are in the health-care profession, co-infections and possibly diabetes to improve the choice of empiric therapy. Tailored treatment based on the extended anamnesis is suggested, and susceptibility testing of the strains is recommended for patients at risk for antibiotic resistance, especially to clarithromycin, fluoroquinolones or both metronidazole and clarithromycin.

High eradication rates of Helicobacter pylori infection following sequential therapy: the Israeli experience treating naïve patients

BACKGROUND

Helicobacter pylori eradication rates following triple therapy are decreasing. Cure rates as low as 57%, mainly to claritromycin resistance, have been reported in Israel. Studies performed in Italy have shown eradication rates of 93%, following sequential therapy. Our aim was to evaluate the effect of sequential therapy on eradication rates of H. pylori in naïve Israeli patients.

MATERIAL AND METHODS

Consecutive patients referred for esophagogastroduodenoscopy with a positive rapid urease test and positive (13) C urea breath test were included. Patients received omeprazole 20 mg bid and amoxicillin 1 g bid for 5 days followed by omeprazole 20 mg bid, clarithromycin 500 mg bid and tinidazole 500 mg bid for the subsequent 5 days. A second (13) C urea breath test was performed at least 4 weeks after completion of therapy. Patients were asked to avoid antibiotics, bismuth compounds or proton pump inhibitor until after the second (13) C urea breath test. Adverse effects were documented by a questionnaire.

RESULTS

One hundred and twenty-four patients (mean age 56.1 ± 12.5 years, 55.6% women) were included; 120/124 (96.8%) completed treatment and performed the second (13) C urea breath test. Two patients (1.6%) were lost to follow-up; 2 (1.6%) were noncompliant with study regulations. One hundred and fifteen patients achieved eradication of H. pylori. The eradication rate was 95.8% by per protocol analysis and 92.7% by intention to treat analysis.

CONCLUSION

The sequential regimen attained significantly higher eradication rates in naïve patients than usually reported for conventional triple therapy. Sequential therapy may be an alternative first-line therapy in eradicating H. pylori in Israel.

Treatment of Helicobacter pylori infection 2010

It is accepted that the success of Helicobacter pylori eradication treatment using standard triple therapy is declining. Resistance, particularly to clarithromycin, has been shown in numerous countries to be rising to a level where the use of standard triple therapy in its current form may no longer be justified. The two major factors influencing resistance are prior exposure to the antibiotic and compliance with therapy. Regimes based on bismuth and levofloxacin, which had previously been mainly second-line options, are now emerging as superior first-line options. Trials of sequential and concomitant therapies are also showing the usefulness of these treatments in different populations. Options for third and subsequent line therapies include furazolidone and rifabutin-based regimes. Susceptibility testing should be performed to maintain accurate data on resistance levels, and has also clinical utility in difficult to eradicate cases. None of these, however, will be successful unless compliance is improved upon. If compliance is assured and eradication confirmation pursued, it has been repeatedly illustrated that near full eradication is achievable.