Clarithromycin-amoxycillin-containing triple therapy: a valid empirical first-line treatment for Helicobacter pylori eradication in Hong Kong?

Benefit and Harm of Aspirin on Mortality From Gastrointestinal Cancers Vs Bleeding in Helicobacter pylori-Eradicated Patients

BACKGROUND & AIMS

We investigated the benefit-risk profile of aspirin on mortality reduction from chemoprevention of gastrointestinal (GI) cancer vs excess mortality from bleeding among Helicobacter pylori-eradicated patients, and its interaction with proton pump inhibitors (PPIs).

METHODS

H pylori-eradicated patients (between 2003 and 2016), identified from a territory-wide database, were observed from the date of H pylori therapy until death or the end of the study (July 2020). Primary exposure was aspirin use as time-varying variable. The primary outcome was GI cancer-related (gastrointestinal, hepatobiliary, or pancreatic cancer) death and the secondary outcome was bleeding-related (gastrointestinal bleeding or intracranial bleeding) death. The adjusted hazard ratio (aHR) of outcomes was calculated by multivariable Cox model after adjusting for age, sex, comorbidities, and concomitant medications. The benefit-risk profile was expressed as the adjusted absolute risk difference of cancer-related deaths and bleeding-related deaths between aspirin users and nonusers.

RESULTS

A total of 87,967 subjects were followed up for a median of 10.1 years, with 1294 (1.5%) GI cancer-related deaths and 304 (0.3%) bleeding-related deaths. Aspirin was associated with lower GI cancer-related mortality (aHR, 0.51; 95% CI, 0.42-0.61), but higher bleeding-related mortality (aHR, 1.52; 95% CI, 1.11-2.08). Among PPI users, the aHR of bleeding-related mortality with aspirin was 1.06 (95% CI, 0.70-1.63). For the whole cohort, the adjusted absolute risk difference between aspirin users and nonusers was 7 (95% CI, 5-8) fewer cancer-related and 1 (95% CI, 0.3-3) more bleeding-related death per 10,000 person-years. Among concomitant PPI-aspirin use, there were 9 (95% CI, 8-10) fewer cancer-related deaths per 10,000 person-years without an increase in bleeding-related deaths.

CONCLUSIONS

GI cancer mortality benefit from aspirin outweighs bleeding-related mortality in H pylori-eradicated subjects, which is enhanced further by PPI use.

Age of eradication and failure rates of clarithromycin-containing triple therapy for Helicobacter pylori: A 15-year population-based study

BACKGROUND

Failure rates of clarithromycin-containing triple therapy for H. pylori are rising. To determine the trend of failure rates of clarithromycin-containing triple therapy in different age groups in Hong Kong over the past 15 years.

MATERIALS AND METHODS

This is a population-based retrospective age-period-cohort study involving all adult H. pylori-infected patients who had received the first course of clarithromycin-containing triple therapy in 2003-2017. Failed eradication was identified by the need of retreatment within 2 years of eradication. Logistic regression model was used to characterize the risk of retreatment.

RESULTS

113,526 H. pylori-infected patients were included. The overall failure rate increased from 4.83% in 2003 to 10.2% in 2016 (p for linear trend <0.001). When stratified by age of eradication, patients 75 years or above had the lowest retreatment rate of 5.11%, which progressively increased in younger patients (60-74 years: OR 1.26, 95% CI 1.15-1.38; 45-59 years: OR 1.36, 95% CI 1.24-1.48; 18-44 years: OR 1.55, 95% CI 1.41-1.69). The results remained consistent when stratified by year of birth, and period of eradication. Other risk factors for retreatment included female (OR 1.24, 95% CI 1.18-1.30), triple therapy containing metronidazole (OR 2.30, 95% CI 2.12-2.50), and shorter duration of therapy (10 days: OR 0.88, 95% CI 0.79-0.97; 14 days: OR 0.67, 95% CI 0.58-0.77 vs 7 days).

CONCLUSIONS

While failure rates of clarithromycin-containing triple therapy progressively increased over the past 15 years, the failure rate was particularly high among younger patients, which could undermine the potential benefits of early H. pylori eradication.

Timing of prior exposure to antibiotics and failure of Helicobacter pylori eradication: a population-based study

BACKGROUND

The success rate of conventional Helicobacter pylori eradication therapy is declining, due to rising antibiotic resistance.

OBJECTIVES

To determine the temporal effects of prior antibiotic exposure on eradication outcome.

PATIENTS AND METHODS

This is a retrospective cohort study including all H. pylori-infected patients who received their first course of clarithromycin-containing triple therapy in 2003-18. Prior antibiotic exposures before H. pylori eradication therapy (up to 180 days, 1 year or 3 years) were retrieved. A logistic regression model was used to evaluate the association between different timings of previous antibiotic exposure, recent (within 30/60 days) or distant period, and the need for retreatment for H. pylori.

RESULTS

A total of 120 787 H. pylori-infected patients were included. Prior exposure to any antibiotics within 180 days was associated with a higher risk of retreatment (OR 1.18, 95% CI 1.13-1.24) and the risk progressively increased with longer duration of antibiotic use. The results were consistent for prior exposure up to 1 year (OR 1.26, 95% CI 1.20-1.31) or 3 years (OR 1.30, 95% CI 1.25-1.35). However, when compared with those without prior antibiotic exposure, recent exposure (within 30 days) did not increase the risk of retreatment, which was consistent for analysis with prior antibiotic exposure up to 3 years. Notably, recent use of cephalosporins within 30/60 days and nitroimidazole within 30 days had significantly lower risks of retreatment.

CONCLUSIONS

Any prior antibiotic exposure increased the risk of treatment failure of clarithromycin-containing triple therapy. Recent exposures to some classes of antibiotics may paradoxically increase treatment success.

Influence of adding vitamin D3 to standard clarithromycin-based triple therapy on the eradication rates of Helicobacter pylori infection

BACKGROUND AND STUDY AIMS

The successful eradication rates with standard clarithromycin-based triple therapy are declining concerning the high antibiotic resistance rate and adverse drug reactions. This study aims to evaluate the effect of adding 1,25-hydroxyvitamin D3 on the eradication rates of the standard clarithromycin-based triple therapy for Helicobacter pylori infection.

PATIENTS AND METHODS

This is a randomized prospective comparative study of 150 patients diagnosed with H. pylori gastritis using magnifying narrow-band imaging endoscopy and supported by a stool antigen test. Patients were divided into two groups: group A (n = 75) treated with amoxicillin, clarithromycin, and esomeprazole for 2 weeks; group B (n = 75) treated with 1,25-hydroxyvitamin D3 for 1 month plus amoxicillin, clarithromycin, and esomeprazole for 2 weeks. The H. pylori eradication rates were assessed using stool antigen test conducted 4 weeks after the end of therapy. Furthermore, the H. pylori eradication rates were assessed with per-protocol (PP) and intention-to-treat (ITT) analyses.

RESULTS

The current results showed that H. pylori eradication was achieved in 46 of 62 (74.19%) and 46 of 75 (61.33%) patients via PP and ITT analyses, respectively, in group A. However, eradication was achieved in 60 of 68 (88.23%) and 60 of 75 (80%) patients via PP and ITT analyses, respectively, in group B. Therefore, the H. pylori eradication rates in the group where vitamin D3 was added to the clarithromycin-based triple therapy were significantly higher than in the other groups (p = 0.012 and p = 0.029 in ITT and PP analyses, respectively).

CONCLUSIONS

Adding vitamin D3 to the standard clarithromycin-based triple therapy could provide an additional advantage to achieve significantly higher eradication rates for H. pylori infection.

Comparative Effectiveness of Multiple Different First-Line Treatment Regimens for Helicobacter pylori Infection: A Network Meta-analysis

BACKGROUND & AIMS

A number of double, triple, and quadruple therapies have been proposed as first-line empiric treatments for Helicobacter pylori infection. However, knowledge of their worldwide and regional comparative efficacy is lacking. We examined the comparative effectiveness of all empirically used first-line regimens tested against standard triple treatment using a network meta-analysis of published randomized controlled trials.

METHODS

Data extracted from eligible randomized controlled trials were entered into a Bayesian network meta-analysis to investigate the comparative efficacy of H pylori infection empiric first-line regimens and to explore their effectiveness rank order. The ranking probability for each regimen was evaluated by means of surfaces under cumulative ranking values.

RESULTS

Sixty-eight eligible randomized controlled trials were included, giving a total of 92 paired comparisons with 22,975 patients randomized to 8 first-line regimens. The overall results showed that only vonoprazan triple therapy and reverse hybrid therapy achieved cure rates of >90%. Levofloxacin triple therapy performed best in Western countries (eradication rate 88.5%). The comparative effectiveness ranking showed that vonoprazan triple therapy had the best results, whereas standard triple therapy was the least efficacious regimen (surfaces under cumulative ranking 92.4% vs 4.7% respectively; odds ratio, 3.80; 95% credible interval, 1.62-8.94).

CONCLUSIONS

For first-line empiric treatment of H pylori infection, vonoprazan triple therapy and reverse hybrid therapy achieved high eradication rates of >90%. Levofloxacin triple therapy achieved the highest eradication rates in Western countries. Standard triple therapy was the least efficacious regimen in this network meta-analysis.

Divergent trends of hospitalizations for upper and lower gastrointestinal bleeding based on population prescriptions of aspirin, proton pump inhibitors and Helicobacter pylori eradication therapy: Trends of upper and lower gastrointestinal bleeding

BACKGROUND

With the increasing use of medications that alter the risk of gastrointestinal bleeding (GIB), comprising aspirin, proton pump inhibitors (PPIs), and Helicobacter pylori eradication therapies, the trends of GIB are evolving.

OBJECTIVE

The aim of this study is to determine and predict the trends of GIB and to evaluate the effects of population prescriptions of these medications on GIB incidences.

METHODS

We retrieved patients hospitalized for GIB in all public hospitals in Hong Kong between 2009 and 2019. Monthly age- and sex-standardized GIB data were fitted and predicted, based on population prescriptions of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), anticoagulants, other antiplatelet drugs, PPIs, and H. pylori therapies, using autoregressive integrated moving average model for time series analysis.

RESULTS

The incidence of upper GIB (UGIB) showed a clear declining trend while lower GIB (LGIB) decreased slightly. Older population (>80 years) had the greatest decline in UGIB but was associated with an increase in LGIB. Prescriptions of PPIs and aspirin increased significantly with time. PPIs prescriptions were negatively associated with UGIB incidence (coefficient log(PPIs) -4.58; 95% confidence interval [CI]: -5.69, -3.47). H. pylori eradication in the previous month showed a nonsignificant trend on UGIB (coefficient -0.14; 95% CI: -0.30, 0.02). In contrast, aspirin increased the incidences of UGIB (coefficient 0.06; 95% CI: 0.04, 0.07) and LGIB (coefficient 0.04; 95% CI: 0.03, 0.05). NSAIDs, anticoagulants, and other antiplatelet drugs were not significantly associated with the trend of either UGIB or LGIB. UGIB is predicted to decline continuously but LGIB is projected to rise, particularly with increasing use of aspirin.

CONCLUSIONS

UGIB incidences were decreasing and had been surpassed by LGIB. Based on population prescriptions of aspirin and PPIs, divergent trends of upper and lower GIB are expected, especially in elderly.

Delay in Retreatment of Helicobacter pylori Infection Increases Risk of Upper Gastrointestinal Bleeding

BACKGROUND & AIMS

Little is known about risk of upper gastrointestinal bleeding (UGIB) in patients failed by Helicobacter pylori eradication therapy. We investigated the effects of different time until retreatment, after failure of initial H pylori eradication therapy, on subsequent risk of UGIB.

METHODS

We performed a territory-wide retrospective cohort study of 70,518 patients with H pylori infection who had received their first course of clarithromycin-based triple therapy from January 2003 through December 2012 in Hong Kong. Patients who required retreatment after failed initial therapy (n = 8330, 11.8%) were categorized based on time between initial and final H pylori eradication (3 months or less, 3-12 months, and more than 12 months). We collected clinical data from 30 days after prescription of the last course of H pylori therapy until hospitalization for non-variceal UGIB, death, or the end of the study (30 Jun 2016; median follow-up time, 7.65 years). The primary outcome was difference in development UGIB (determined from ICD-9 codes) between patients who required retreatment and those who did not (reference group).

RESULTS

Compared with the reference group, patients who required retreatment had an overall higher risk of UGIB, even after last eradication therapy (adjusted hazard ratio (HR), 1.50, 95% CI, 1.34-1.69). There was a progressive increase in risk of UGIB with longer time from initial until final eradication therapy: hazard ratio for time less than 3 months, 1.16; 95% CI, 0.88-1.54, hazard ratio for time 3-12 months, 1.35; 95% CI, 1.07-1.69, and hazard ratio for time more than 12 months, 1.68; 95% CI, 1.46-1.94 (P for trend = .038).

CONCLUSION

In a retrospective study of patients in Hong Kong, we found that those failed by initial H pylori eradication have an increased risk of UGIB, compared to patients who responded to the initial therapy. Risk increased progressively with longer time until retreatment. Early retreatment within 3 months should be considered to minimize subsequent UGIB risk.

Nonaspirin nonsteroidal anti-inflammatory drugs and gastric cancer risk after Helicobacter pylori eradication: A territory-wide study

BACKGROUND

Despite Helicobacter pylori (HP) eradication, individuals can still develop gastric cancer (GC). Prior studies have demonstrated that nonaspirin nonsteroidal anti-inflammatory drugs (NA-NSAIDs) reduce the risk of GC, but this may be caused by immortal time bias and failure to adjust for HP status. The objective of this study was to investigate whether NA-NSAIDs reduced the risk of GC in patients who undergo H. pylori eradication.

METHODS

Adult patients who had received clarithromycin-based triple therapy between 2003 and 2016 were identified from a territory-wide health care database. Exclusion criteria included prior GC or GC diagnosed <6 months after HP eradication, prior gastrectomy, gastric ulcer after HP eradication, and failure of triple therapy. Covariates included age, sex, prior peptic ulcer disease, other comorbidities, and concurrent medications (aspirin, proton pump inhibitors, statins, and metformin). To avoid immortal time bias, NA-NSAID use (≥90 days) was treated as a time-dependent variable in a multivariable Cox model (time-dependent analysis). Time-independent analysis was also performed.

RESULTS

During a median follow-up of 8.9 years (interquartile range, 5.4-12.6 years), 364 of 92,017 patients (0.4%) who underwent HP eradication developed GC. NA-NSAID use was associated with a significant reduction in the risk of GC in time-fixed analysis (adjusted hazard ratio [aHR], 0.65; 95% CI, 0.47-0.90), but not in time-dependent multivariable analysis (aHR, 1.35; 95% CI, 0.97-1.87). Time-dependent subgroup analyses also did not indicate any significant association between NA-NSAID use and either cardia GC (aHR, 0.75; 95% CI, 0.27-2.06) or noncardia GC (aHR, 1.28; 95% CI, 0.83-1.98).

CONCLUSIONS

NA-NSAID use was not associated with a reduced risk of GC among patients who underwent HP eradication. The chemopreventive effect of NA-NSAIDs observed in prior studies may have been confounded by immortal time bias.

Calcium channel blockers are associated with lower gastric cancer risk: A territory-wide study with propensity score analysis

Prior studies showed that calcium channel blockers (CCBs) could modify cancer risk, but data on gastric cancer (GC) are limited. We aimed to investigate whether CCBs could modify GC risk in Helicobacter pylori-eradicated patients. H pylori-infected patients with hypertension who are aged ≥50 and had received clarithromycin-based triple therapy between 2003 and 2016 were identified from a territory-wide healthcare database. Patients with eradication failure, GC diagnosed within 6 months after HP eradication, and gastric ulcer were excluded. Time-fixed Cox model with one-to-one propensity score matching was used to calculate hazard ratio (HR) of GC with CCBs. Sensitivity analysis using time-dependent multivariable Cox model in which CCB use was treated as time-varying covariate was also performed to address immortal time bias. 17 622 (29.6%) H pylori-eradicated patients with hypertension were included. During a median follow-up of 8.6 years, 105 (0.6%) developed GC. After PS matching, CCBs were associated with a lower GC risk (HR: 0.56; 95% CI: 0.32-0.97). Time-dependent analysis showed consistent result (aHR: 0.50; 95% CI: 0.33-0.75). A longer duration of CCB use was associated with even lower GC risk (adjusted HR [aHR]: 0.69; 95% CI: 0.61-0.79 for every 1-year increase in use). Long-acting CCBs (aHR: 0.47; 95% CI: 0.29-0.76) and dihydropyridines (aHR: 0.49; 95% CI: 0.32-0.73) conferred greater benefit than short-acting ones (aHR: 0.60; 95% CI: 0.36-1.03) and nondihydropyridines (aHR: 0.76; 95% CI: 0.24-2.48). The aHR was 0.57 (95% CI: 0.34-0.97) for noncardia and 0.59 (95% CI: 0.27-1.31) for cardia cancer. Use of CCBs was associated with lower risk of GC development in H pylori-eradicated patients, in a duration- and dose-response manner.

Bovine lactoferrin enhances the efficacy of levofloxacin-based triple therapy as first-line treatment of Helicobacter pylori infection: an in vitro and in vivo study

Objectives

To evaluate the in vitro antimicrobial/antivirulence action of bovine lactoferrin and its ability to synergize with levofloxacin against resistant Helicobacter pylori strains and to analyse the effect of levofloxacin, amoxicillin and esomeprazole with and without bovine lactoferrin as the first-line treatment for H. pylori infection.

Methods

The bovine lactoferrin antimicrobial/antivirulence effect was analysed in vitro by MIC/MBC determination and twitching motility against six clinical H. pylori strains and a reference strain. The synergism was evaluated using the chequerboard assay. The prospective therapeutic trial was carried out on two separate patient groups, one treated with esomeprazole/amoxicillin/levofloxacin and the other with esomeprazole/amoxicillin/levofloxacin/bovine lactoferrin. Treatment outcome was determined with the [¹³C]urea breath test.

Results

In vitro, bovine lactoferrin inhibited the growth of 50% of strains at 10 mg/mL and expressed 50% bactericidal effect at 40 mg/mL. The combination of levofloxacin and bovine lactoferrin displayed a synergistic effect for all strains, with the best MIC reduction of 16- and 32-fold for levofloxacin and bovine lactoferrin, respectively. Bovine lactoferrin at one-fourth MIC reduced microbial motility significantly for all strains studied. In the in vivo study, 6 of 24 patients recruited had treatment failure recorded with esomeprazole/amoxicillin/levofloxacin (75% success, 95% CI 57.68%–92.32%), and in the group with esomeprazole/amoxicillin/levofloxacin/bovine lactoferrin, 2 out of 53 patients recruited had failure recorded (96.07% success, 95% CI 90.62%–101.38%).

Conclusions

Bovine lactoferrin can be considered a novel potentiator for restoring susceptibility in resistant H. pylori strains. Bovine lactoferrin added to a triple therapy in first-line treatment potentiates the therapeutic effect.

Metformin Use and Gastric Cancer Risk in Diabetic Patients After Helicobacter pylori Eradication

BACKGROUND

Although prior studies showed metformin could reduce gastric cancer (GC) risk in patients with diabetes mellitus, they failed to adjust for Helicobacter pylori infection and glycemic control. We aimed to investigate whether metformin reduced GC risk in H. pylori-eradicated diabetic patients and its association with glycemic control.

METHODS

This was a territory-wide cohort study using hospital registry database, recruiting all diabetic patients who were prescribed clarithromycin-based triple therapy for H. pylori infection from 2003 to 2012. Subjects were observed from H. pylori therapy prescription until GC diagnosis, death, or end of study (December 2015). Exclusion criteria included GC diagnosed within first year of H. pylori therapy, prior history of GC or gastrectomy, and failure of H. pylori eradication. The hazard ratio (HR) of GC with metformin (defined as at least 180-day use) was estimated by Cox model with propensity score adjustment for covariates (age, sex, comorbidities, medications [including insulin], and time-weighted average hemoglobin A1c [HbA1c]). All statistical tests were two-sided.

RESULTS

During a median follow-up of 7.1 years (IQR = 4.7-9.8), 37 (0.51%) of 7266 diabetic patients developed GC at a median age of 76.4 years (IQR = 64.8-81.5 years). Metformin use was associated with a reduced GC risk (adjusted HR = 0.49, 95% CI = 0.24 to 0.98). There was a trend towards a lower GC risk with increasing duration (Ptrend = .01) and dose of metformin (Ptrend = .02). HbA1c level was not an independent risk factor for GC.

CONCLUSIONS

Metformin use was associated with a lower GC risk among H. pylori-eradicated diabetic patients in a duration- and dose-response manner, which was independent of HbA1c level.

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.

Is tailored therapy based on antibiotic susceptibility effective ? a multicenter, open-label, randomized trial

An effective eradication therapy of Helicobacter pylori (H. pylori) should be used for the first time. In this study, we assessed whether tailored therapy based on antibiotic susceptibility testing is more effective than traditional therapy. We also evaluated the factors that cause treatment failure in high-resistance areas. For this multicenter trial, we recruited 467 H. pylori-positive patients. The patients were randomly assigned to receive tailored triple therapy (TATT), tailored bismuth-containing quadruple therapy (TABQT), or traditional bismuth-containing quadruple therapy (TRBQT). For the TATT and TABQT groups, antibiotic selection proceeded via susceptibility testing using an agar-dilution test. The patients in the TRBQT group were given amoxicillin, clarithromycin, esomeprazole, and bismuth. Successful eradication was defined as a negative ¹³C-urea breath test at least eight weeks after the treatment ended. Susceptibility testing was conducted using an agar-dilution test. The eradication rate was examined via intention-to-treat (ITT) and per-protocol (PP) analyses. The clarithromycin, levofloxacin, and metronidazole resistance rates were 26.12%, 28.69%, and 96.79%, respectively. Resistance against amoxicillin and furazolidone was rare. The eradication rates for TATT, TRBQT, and TABQT were 67.32%, 63.69%, and 85.99% in the ITT analysis (P 0.001) and 74.64%, 68.49%, and 91.22% in the PP analysis (P 0.001), respectively. The efficacy of TABQT was affected by clarithromycin resistance, and bismuth exerted a direct influence on TATT failure. TABQT was the most efficacious regimen for use in high-resistance regions, especially among clarithromycin-susceptible patients.

Statins Were Associated with a Reduced Gastric Cancer Risk in Patients with Eradicated Helicobacter Pylori Infection: A Territory-Wide Propensity Score Matched Study

BACKGROUND

Individuals may still develop gastric cancer even after Helicobacter pylori eradication. We aimed to investigate statin effect on gastric cancer development in H. pylori-eradicated subjects.

METHODS

All adult subjects who were prescribed clarithromycin-based triple therapy between 2003 and 2012 were identified in this retrospective cohort study utilizing a territory-wide electronic healthcare database. Patients were observed from index date of H. pylori therapy, and censored at gastric cancer diagnosis, death, or December 2015 (study end date). Statin use was defined as ≥180-day use after index date. Exclusion criteria included gastric cancer diagnosed within the first year after index date, previous gastric cancer or gastrectomy, and H. pylori treatment failure. Subdistribution hazard ratio (SHR) of gastric cancer with statins was calculated by competing risk regression with propensity score (PS) analysis matching 19 variables (age, sex, comorbidities, and other drug usage, including proton pump inhibitors, nonsteroidal anti-inflammatory drugs, aspirin, cyclooxygenase-2 inhibitors, and metformin).

RESULTS

During a median follow-up of 7.6 years (interquartile range = 5.1-10.3), 169 (0.27%) of 63,605 patients developed gastric cancer at an incidence rate of 3.5 per 10,000 person-years. Among 22,870 PS-matched subjects, statins were associated with a lower gastric cancer risk (SHR = 0.34; 95% confidence interval, 0.19-0.61), in a duration- and dose-response manner (P _trend < 0.05).

CONCLUSIONS

Statins were associated with a lower gastric cancer risk in a duration- and dose-response manner among H. pylori-eradicated patients.

IMPACT

This study provides evidence on the additional benefits of statins as chemopreventive agents against gastric cancer among H. pylori-eradicated patients.

Diabetes Increases Risk of Gastric Cancer After Helicobacter pylori Eradication: A Territory-Wide Study With Propensity Score Analysis

OBJECTIVE

Whether diabetes mellitus (DM) increases risk of gastric cancer (GC) remains controversial because of inadequate adjustments for important risk factors, including Helicobacter pylori (HP) infection status, concomitant medication use, and cancer site. We investigated whether type 2 DM increased risk of GC in patients after they received treatment for HP infection.

RESEARCH DESIGN AND METHODS

This was a territory-wide cohort study of patients aged ≥45 years who had received clarithromycin-based triple therapy for HP infection between 2003 and 2012 in Hong Kong. Data were retrieved from a public electronic health database. Observation started from receipt of therapy for HP infection to GC diagnosis, death, or the end of the study (December 2015). Exclusion criteria included type 1 DM, GC diagnosed within the 1st year of HP therapy, prior GC or gastrectomy, and retreatment for HP infection. The adjusted hazard ratio (aHR) of GC with type 2 DM was calculated by using a Cox model that adjusted for 20 covariates (age, sex, comorbidities, and medications) through propensity score regression.

RESULTS

During a median follow-up of 7.1 years (interquartile range 4.8-9.3 years), 153 of 46,460 patients (0.33%) developed GC at a median age of 72.4 years. Type 2 DM was associated with an increased risk of GC (aHR 1.73 [95% CI 1.08-2.79]). Stratified analysis showed an increase in risk for cardia cancer only (aHR 3.40 [95% CI 1.45-7.97]) and in those with suboptimal DM control (time-weighted mean HbA_1c ≥6.0% [42 mmol/mol]; aHR 1.68 [95% CI 1.07-2.63]).

CONCLUSIONS

Type 2 DM is associated with an increased risk of GC among patients in whom HP was eradicated, in particular gastric cardia cancer and in those with suboptimal DM control.

Aspirin and Risk of Gastric Cancer After Helicobacter pylori Eradication: A Territory-Wide Study

Background

Despite successful H. pylori (HP) eradication, some individuals remain at risk of developing gastric cancer (GC). Previous studies showed that aspirin was associated with a reduced GC risk. However, whether aspirin can reduce GC risk in HP-eradicated subjects remains unknown. We aimed to determine the chemopreventive effect of aspirin in HP-eradicated subjects.

Methods

We identified subjects who had received a prescription of clarithromycin-based triple therapy for HP between 2003 and 2012 from a territory-wide health care database. The observation period started from commencement of HP therapy (index date), and the follow-up was censored at the end of the study (December 2015), death, or GC diagnosis. Aspirin use was defined as use once or more often weekly. Subjects who failed HP eradication or were diagnosed with GC within 12 months of HP therapy were excluded. The hazard ratio (HR) of GC with aspirin use was calculated by Cox model with Propensity Score adjustment for age, sex, comorbidities, and concurrent medications. All statistical tests were two-sided.

Results

The median follow-up was 7.6 years (interquartile range [IQR] = 5.1-10.3 years), and 169 (0.27%) out of 63 605 patients developed GC. The incidence rate of GC was 3.5 per 10 000 person-years. Aspirin use was associated with a reduced GC risk (HR = 0.30, 95% confidence interval [CI] = 0.15 to 0.61). The risk of GC decreased with increasing frequency, duration, and dose of aspirin (all Ptrend < .001).

Conclusions

Aspirin use was associated with a frequency-, dose-, and duration-dependent reduction in GC risk after HP eradication. The effect was most prominent in those who used aspirin daily or for five or more years.

Effects of Helicobacter pylori Treatment on Incidence of Gastric Cancer in Older Individuals

BACKGROUND & AIMS

Although eradication of Helicobacter pylori infection reduces the risk of gastric cancer, few data are available on its effects in older subjects. We compared the age-specific risk of gastric cancer in a large cohort of subjects who received H pylori eradication therapy vs a matched general population.

METHODS

We searched the Hospital Authority database of Hong Kong to identify individuals with H pylori infection who had received a course of clarithromycin-containing eradication therapy from January 2003 through December 2012. We compared the gastric cancer incidence in this cohort with the expected incidence for the local general population by retrieving the gastric cancer incidence of the age- and sex-matched population from 2003 through 2014 (the latest available year) from the Hong Kong Cancer Registry. The primary outcome was the incidence of gastric cancer development in the cohort treated for H pylori infection vs the expected number of gastric cancer cases in the general population. Analyses were conducted by a priori age groups of less than 40 years, 40-59 years, and 60 years or older.

RESULTS

Among 73,237 subjects infected with H pylori who received eradication therapy, 200 (0.27%) developed gastric cancer during a median follow-up time of 7.6 years. Compared with the matched general population, the gastric cancer risk was significantly lower in subjects 60 years or older who had received H pylori treatment (standardized incidence ratio [SIR], 0.82; 95% confidence interval [CI], 0.69-0.97; P = .02) but not in younger groups. When data were stratified based on time from H pylori treatment (less than 5 years, 5-9 years, and 10 or more years), the risk of gastric cancer was significantly lower than the general population 10 or more years after eradication in the group 40-59 years old (SIR 0.32; 95% CI, 0.08-0.88; P = .04) and the group 60 years or older (SIR, 0.42; 95% CI, 0.42-0.84; P = .02) than the other age groups.

CONCLUSIONS

In an analysis of data from a public hospital database on Hong Kong, we associated treatment of H pylori infection with a lower risk of gastric cancer, particularly in older subjects, 10 or more years after treatment.

Long-term proton pump inhibitors and risk of gastric cancer development after treatment for Helicobacter pylori: a population-based study

OBJECTIVE

Proton pump inhibitors (PPIs) is associated with worsening of gastric atrophy, particularly in Helicobacter pylori (HP)-infected subjects. We determined the association between PPIs use and gastric cancer (GC) among HP-infected subjects who had received HP therapy.

DESIGNS

This study was based on a territory-wide health database of Hong Kong. We identified adults who had received an outpatient prescription of clarithromycin-based triple therapy between year 2003 and 2012. Patients who failed this regimen, and those diagnosed to have GC within 12 months after HP therapy, or gastric ulcer after therapy were excluded. Prescriptions of PPIs or histamine-2 receptor antagonists (H2RA) started within 6 months before GC were excluded to avoid protopathic bias. We evaluated GC risk with PPIs by Cox proportional hazards model with propensity score adjustment. H2RA was used as a negative control exposure.

RESULT

Among the 63 397 eligible subjects, 153 (0.24%) developed GC during a median follow-up of 7.6 years. PPIs use was associated with an increased GC risk (HR 2.44, 95% CI 1.42 to 4.20), while H2RA was not (HR 0.72, 95% CI 0.48 to 1.07). The risk increased with duration of PPIs use (HR 5.04, 95% CI 1.23 to 20.61; 6.65, 95% CI 1.62 to 27.26 and 8.34, 95% CI 2.02 to 34.41 for ≥1 year, ≥2 years and ≥3 years, respectively). The adjusted absolute risk difference for PPIs versus non-PPIs use was 4.29 excess GC (95% CI 1.25 to 9.54) per 10 000 person-years.

CONCLUSION

Long-term use of PPIs was still associated with an increased GC risk in subjects even after HP eradication therapy.

The Changing Profile of Helicobacter pylori Antibiotic Resistance in Singapore: A 15-Year Study

BACKGROUND

Antibiotic resistance is an important cause of H. pylori treatment failure. This study aimed to examine the change in H. pylori antibiotic resistance profile in Singapore over the course of 15 years.

MATERIALS AND METHODS

The study period was from 2000 to 2014. Gastric mucosal biopsies obtained from H. pylori-positive patients were cultured. Antibiotic susceptibility to metronidazole, clarithromycin, levofloxacin, tetracycline, and amoxicillin was tested. The change in resistance rates over time was analyzed.

RESULTS

A total of 708 H. pylori isolates were cultured. There was a significant increase in resistance rates for metronidazole (2000-2002: 24.8%; 2012-2014: 48.2%; p < .001), clarithromycin (2000-2002: 7.9%; 2012-2014: 17.1%; p = .022), and levofloxacin (2000-2002: 5%; 2012-2014: 14.7%; p = .007). The resistance rates for tetracycline (2000-2002: 5%; 2012-2014: 7.6%) and amoxicillin (2000-2002: 3%; 2012-2014: 4.4%) remained stable. Increase in dual (2000-2002: 6.9%; 2012-2014: 9.4%; p = .479) and triple antibiotic resistance rates (2000-2002: 0; 2012-2014: 7.6%; p < .001) were observed. Overall, the most common dual and triple resistance patterns were metronidazole/clarithromycin (4.4%) and metronidazole/clarithromycin/levofloxacin (1.8%), respectively.

CONCLUSIONS

Over 15 years, H. pylori resistance rates to metronidazole, clarithromycin and levofloxacin had increased. There was increased resistance to multiple antibiotics.

The Association of Age and Antibiotic Resistance of Helicobacter Pylori: A Study in Jiaxing City, Zhejiang Province, China

The antibiotic resistance of Helicobacter pylori (H pylori) is steadily increasing worldwide, resulting in the low efficiency of the current therapeutic approaches for eradication. In this study, we investigated the relationship between antibiotic resistances, the year of sample collection, and the ages of the infected individuals.A total of 29,034 gastric mucosa biopsy samples were randomly collected from January 1, 2009 to December 9, 2014 in Jiaxing City, Zhejiang Province, China. An antibiotic susceptibility testing was determined using an agar-dilution method. The statistical significance was tested using the chi-squared (χ) test.A total of 9687 strains were isolated. The resistance rate to clarithromycin, levofloxacin, and metronidazole were 17.76%, 19.66%, and 95.5%, respectively. Resistance was rare against amoxicillin, gentamicin, and furazolidone. The metronidazole resistance rate stayed at a consistently high level. In contrast, the resistance rates of clarithromycin and levofloxacin increased rapidly from 2009 to 2011, gradually decreased from 2012 to 2013, and then increased again in 2014. Although patients ages 31 to 50 and 71 to 80 years had lower infection rates of H pylori, they also had higher resistance rates to clarithromycin and levofloxacin. The highest antibiotic resistance rate was observed in patients' ages 71 to 80 years old. Younger patients (below 30 years old) had a lower resistance to levofloxacin. Patients' ages 51 to 60 years old may thus represent an important category for the future study of H pylori infection.Age plays a key element in H pylori resistance to clarithromycin and levofloxacin. It is therefore necessary to consider individualized therapy for the optimized treatment of H pylori-infected patients.

Seven-day triple therapy is a better choice for Helicobacter pylori eradication in regions with low antibiotic resistance

AIM: To investigate whether 7-d triple therapies are still valid in populations with low levels of resistance.

METHODS: A total of 1106 Helicobacter pylori (H. pylori)-positive patients were divided into three groups, each of which received one type of 7-d triple therapy. Therapeutic outcomes of the patients were assessed by the ¹³C-urea breath test at 8 wk after treatment. The susceptibility of H. pylori to antibiotics was determined by an agar-dilution method. Data analysis was performed by χ² tests.

RESULTS: The eradication rates in groups A, B and C were 90.71% (332/366), 90.46% (313/346) and 90.87% (189/208), respectively (P = 0.986). The resistance rates were 8.91% for clarithromycin, 14.78% for levofloxacin and 0% for amoxicillin. The eradication rate was significantly different between clarithromycin- and levofloxacin-resistant patients (P < 0.05) in group A. Patients whose treatment failed in group A also had a higher clarithromycin resistance rate than did successive patients (P = 0.034). However, levofloxacin resistance had no obvious influence on the eradication rate. Furthermore, three main antibiotics (clarithromycin, levofloxacin and amoxicillin) had lower DID (defined daily dose per 1000 inhabitants per day) in this city.

CONCLUSION: Clarithromycin resistance is the main reason for the failure of 7-d triple therapy. In populations with low levels of resistance, a 7-d triple therapy is a viable choice. The choice of therapy should not be influenced by conditions in high antibiotic resistance regions.

Comparative effectiveness and tolerance of treatments for Helicobacter pylori: systematic review and network meta-analysis

OBJECTIVE

To determine the most efficacious treatment for eradication of Helicobacter pylori with the lowest likelihood of some common adverse events among pre-recommended and newer treatment regimens.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Cochrane Library, PubMed, and Embase without language or date restrictions.

STUDY SELECTION

Full text reports of randomised controlled trials that compared different eradication treatments for H pylori among adults.

RESULTS

Of the 15,565 studies identified, 143 were eligible and included. Data on 14 kinds of treatments were available. Of 91 possible comparisons for the efficacy outcome, 34 were compared directly and the following treatments performed better: seven days of concomitant treatment (proton pump inhibitor and three kinds of antibiotics administered together), 10 or 14 days of concomitant treatment, 10 or 14 days of probiotic supplemented triple treatment (standard triple treatment which is probiotic supplemented), 10 or 14 days of levofloxacin based triple treatment (proton pump inhibitor, levofloxacin, and antibiotic administered together), 14 days of hybrid treatment (proton pump inhibitor and amoxicillin used for seven days, followed by a proton pump inhibitor, amoxicillin, clarithromycin, and 5-nitroimidazole for another seven days), and 10 or 14 days of sequential treatment (five or seven days of a proton pump inhibitor plus amoxicillin, followed by five or seven additional days of a proton pump inhibitor plus clarithromycin and 5-nitroimidazole or amoxicillin). In terms of tolerance, all treatments were considered tolerable, but seven days of probiotic supplemented triple treatment and seven days of levofloxacin based triple treatment ranked best in terms of the proportion of adverse events reported.

CONCLUSION

Comparison of different eradication treatments for H pylori showed that concomitant treatments, 10 or 14 days of probiotic supplemented triple treatment, 10 or 14 days of levofloxacin based triple treatment, 14 days of hybrid treatment, and 10 or 14 days of sequential treatment might be better alternatives for the eradication of H pylori.

Is levofloxacin-based triple therapy an alternative for first-line eradication of Helicobacter pylori? A systematic review and meta-analysis

OBJECTIVES

To evaluate the available data on the efficacy and safety of levofloxacin-based triple therapy compared with standard triple therapy in first-line treatment for Helicobacter pylori infection.

METHODS

By searching MEDLINE, The Cochrane Central Register of Controlled Trials, and Web of Knowledge, two independent reviewers systemically identified randomized controlled trials comparing levofloxacin-based triple regimen with standard triple therapy for first-line treatment of H. pylori infection. The pooled risk ratios (RR) and 95% confidence intervals were calculated.

RESULTS

Overall, nine randomized controlled trials including 1275 patients have been treated with levofloxacin-based triple therapy and 1237 patients with standard regimen. Eradication rate in the levofloxacin-based therapy group was slightly higher than that in the standard triple therapy group regardless of treatment duration (80.2% vs. 77.4%, RR=1.03, 95% CI=0.94-1.13). Subgroup analysis related to different geographic areas found that efficacy of 7-day standard triple regimen was statistically superior to 7-day levofloxacin-based scheme in Asian group (RR=0.91, 95% CI=0.86-0.97), but levofloxacin-based triple therapy was predominant regardless of treatment time in European countries (RR=1.15, 95% CI=1.06-1.23). There was no significant difference between two groups in the incidence of overall adverse events or in the occurrence of discontinuing therapy due to side effects.

CONCLUSIONS

The 10-day levofloxacin-based triple therapy may be considered as an alternative for increasing cure rate of H. pylori infection in European areas. But in Asian countries, standard triple regimen is still superior to levofloxacin-based therapy as first-line regimen for H. pylori eradication.

Levofloxacin and proton pump inhibitor-based triple therapy versus standard triple first-line therapy for Helicobacter pylori eradication

BACKGROUND

Standard triple therapy for Helicobacter pylori infection fails in up to one quarter of patients. Levofloxacin-based triple therapy may be more efficacious.

OBJECTIVE

The aim of this paper was to compare levofloxacin and proton pump inhibitor-based triple therapy with standard triple therapy for H. pylori infection.

METHODS

PubMed, Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Google Scholar, and Ovid were systematically searched to identify randomized controlled trials comparing levofloxacin and proton pump inhibitor-based therapy with standard triple therapy in treatment-naive patients with H. pylori infection until August 2013.

RESULTS

Ten randomized controlled trials involving 2676 patients (1357 in the levofloxacin group and 1319 in the control group) met the inclusion criteria. The pooled odds ratio by intention-to-treat analysis and by per protocol analysis in the levofloxacin regimen versus standard regimen was 1.28 [95% confidence interval (CI): 0.88-1.85] and 1.23 (95% CI: 0.82-1.84) by the random effects model, respectively. There was no statistical significance of the incidence of total side effects between the groups, but levofloxacin-based therapy was associated with a significant reduction in the incidence of taste disturbance compared with standard third therapy.

CONCLUSION

Levofloxacin-based therapy was as safe and effective as triple therapy for H. pylori infection and could be considered as an additional treatment option. However, more rigorous research is required to accurately assess the role of levofloxacin in eradicating H. pylori infection.

Levofloxacin-based first-line therapy versus standard first-line therapy for Helicobacter pylori eradication: meta-analysis of randomized controlled trials

Background

First-line levofloxacin-based treatments eradicate Helicobacter pylori with varying success. We examined the efficacy and safety of first-line levofloxacin-based treatment in comparison to standard first-line therapy for H pylori eradication.

Materials and Methods

We searched literature databases from Medline, EMBASE, and the Cochrane Register of Randomized Controlled Trials through March 2013 for randomized controlled trials comparing first-line levofloxacin and standard therapy. We included randomized controlled trials conducted only on naïve H pylori infected patients in adults. A systematic review was conducted. Meta-analysis was performed with Review Manager 5.2. Treatment effect was determined by relative risk with a random or fixed model by the Mantel-Haenszel method.

Results

Seven trials were identified with 888 patients receiving 7 days of first-line levofloxacin and 894 treated with standard therapy (Amoxicillin, Clarithromycin and proton pump inhibitor) for 7 days. The overall crude eradication rate in the Levofloxacin group was 79.05% versus 81.4% in the standard group (risk ratio 0.97; 95% CI; 0.93, 1.02). The overall dropout was 46 (5.2%) in the levofloxacin group and 52 (5.8%) for standard therapy. The dizziness was more common among group who took Levofloxacin based treatment and taste disturbance was more common among group who took standard therapy. Meta-analysis of overall adverse events were similar between the two groups with a relative risk of 1.06 (95% CI 0.72, 1.57).

Conclusion

Helicobacter pylori eradication with 7 days of Levofloxacin-based first line therapy was safe and equal compared to 7 days of standard first-line therapy.

Levofloxacin-containing triple and sequential therapy or standard sequential therapy as the first line treatment for Helicobacter pylori eradication in China

AIMS

To compare the efficacy and the adverse effects of levofloxacin-containing triple therapy, standard sequential therapy, and levofloxacin-containing sequential therapy as first-line treatment for Helicobacter pylori eradication.

METHODS

Three hundred and forty-five naive H. pylori-positive patients were randomized to receive levofloxacin-containing 7-day triple therapy (Levo triple, i.e., esomeprazole, 20 mg, twice daily, amoxicillin, 1 g, twice daily, and levofloxacin, 500 mg, once daily for 7 days, n = 114), standard sequential therapy (SST-10, 5-day esomeprazole, 20 mg, twice daily and amoxicillin, 1 g, twice daily followed by 5-day esomeprazole, 20 mg, twice daily, clarithromycin, 500 mg, twice daily and tinidazole, 500 mg, twice daily for 5 days, n = 115) or levofloxacin-containing sequential therapy (Levo-ST-10, 5-day esomeprazole, 20 mg, twice daily and amoxicillin, 1 g, twice daily for 5 days followed by 5-day esomeprazole, 20 mg, twice daily, levofloxacin, 500 mg, once daily and tinidazole, 500 mg, twice daily, n = 116). Eradication was confirmed by a (13) C-urea breath test 4 weeks after completion of treatment.

RESULTS

Intention to treat (ITT) eradication rates were 78.1% (95% CI: 69.4, 85.3%), 78.3% (95% CI: 69.6, 85.4%), and 82.8% (95% CI: 74.6, 89.1%) for Levo triple, SST-10, Levo-ST-10, respectively (p = .599). Per protocol (PP) eradication rates were 80.9% (95% CI: 72.3, 87.8%), 82.6% (95% CI: 74.1, 89.2%), and 86.5% (95% CI: 78.7, 92.2%), respectively, for the three therapies (p = .513). Overall, 3.8% experienced mild to moderate adverse events; the rates were 1.75, 4.35, and 5.17%, respectively, in the three groups (p = .325).

CONCLUSIONS

Standard sequential therapy and 7-day levofloxacin triple therapy produced unacceptably therapeutic efficacy in China. Only levofloxacin-containing sequential therapy achieved borderline acceptable result. None of the regimens tested reliably achieved 90% or greater therapeutic efficacy in China.

Eradication of Helicobacter pylori for prevention of ulcer recurrence after simple closure of perforated peptic ulcer: a meta-analysis of randomized controlled trials

BACKGROUND

Eradication of Helicobacter pylori has become part of the standard therapy for peptic ulcer. However, the role of H pylori eradication in perforation of peptic ulcers remains controversial. It is unclear whether eradication of the bacterium confers prolonged ulcer remission after simple repair of perforated peptic ulcer.

METHODS

A systematic review and meta-analysis of randomized controlled trials was performed to evaluate the effects of H pylori eradication on prevention of ulcer recurrence after simple closure of perforated peptic ulcers. The primary outcome to evaluate these effects was the incidence of postoperative ulcers; the secondary outcome was the rate of H pylori elimination.

RESULTS

The meta-analysis included five randomized controlled trials and 401 patients. A high prevalence of H pylori infection occurred in patients with perforated peptic ulcers. Eradication of H pylori significantly reduced the incidence of ulcer recurrence at 8 wk (risk ratio 2.97; 95% confidence interval: 1.06-8.29) and 1 y (risk ratio 1.49; 95% confidence interval: 1.10-2.03) postoperation. The rate of H pylori eradication was significantly higher in the treatment group than in the nontreatment group.

CONCLUSIONS

Eradication therapy should be provided to patients with H pylori infection after simple closure of perforated gastroduodenal ulcers.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

High Helicobacter pylori resistance to metronidazole but zero or low resistance to clarithromycin, levofloxacin, and other antibiotics in Malaysia

OBJECTIVE

Bacterial resistance to antibiotics is the single most important determinant of treatment success. The objective of this study was to determine the prevalence of Helicobacter pylori resistance to clarithromycin, amoxicillin, metronidazole, tetracycline, levofloxacin, rifabutin, and furazolidone in our local bacterial strains.

METHODS

Samples from consecutive ninety patients were obtained for culture and sensitivity testing. Resistance to individual antibiotics were tested using the E-test and MIC(90) read from the strips. Resistance to rifampicin and nitrofurantoin were used as a surrogate for rifabutin and furazolidine.

RESULTS

There was a high prevalence of resistance to metronidazole 68/90 (75.5%). No male (34/45 (75.5%) versus female (35/45 (77.7%) difference in frequency of metronidazole resistance was noted (p = 1.000). There was zero resistance (0) to clarithromycin, levofloxacin, amoxicillin, and nitrofurantoin/furazolidone. Resistance to rifampicin/rifabutin was for breakpoints of 1 and 4 μg/mL of 14.4 and 2.2% respectively.

CONCLUSIONS

Although there was high bacterial resistance to metronidazole, the absence of resistance particularly to the key antibiotics used in H. pylori eradication therapy: clarithromycin and levofloxacin is reassuring to note. Continued monitoring of antibiotic resistance should be carried out.

Levofloxacin susceptibility testing for Helicobacter pylori in China: comparison of E-test and disk diffusion method

BACKGROUND

 The aims of this study were to compare disk diffusion with E-test method for levofloxacin susceptibility testing of Helicobacter pylori and standardized breakpoints for disk diffusion as a stable and reliable method for determining qualitative levofloxacin susceptibility.

MATERIALS AND METHODS

 We determined the levofloxacin susceptibility of 45 H. pylori strains isolated from Chinese patients by the E-test method. Disk diffusion was evaluated as an alternative method to determine susceptibility and compared with the E-test results by linear regression analysis.

RESULTS

 The minimum inhibitory concentration (MIC) values tested by E-test method ranged from 0.047 to 32 μg/mL. Resistance to levofloxacin was detected in 16 (35.6%) isolates. The levofloxacin disk zone sizes obtained by disk diffusion method correlated well (r² = .877) with the MICs obtained by E-test method. As a consequence of regression analysis, isolates with inhibition diameters < 12 mm were considered resistant to levofloxacin. There was 100% agreement between the two methods for levofloxacin, applying the regression-based breakpoints.

CONCLUSIONS

The disk diffusion method is equivalent to the E-test method for testing levofloxacin susceptibility of H. pylori strains; it is more practical and inexpensive, and it is suitable for the analysis of a small number of isolates compared with the E-test method.