Epidemiology of the antibiotic resistance of Helicobacter pylori in Canada.

BACKGROUND: The rate of Helicobacter pylori resistance to antibiotics determines the cure rate of treatment regimens containing such antibiotics. AIMS: To review the literature to determine the rates of H pylori resistance to metronidazole and clarithromycin in Canada, and whether these rates vary in different regions of Canada. METHODS: The literature was reviewed extensively for the prevalence of antibiotic-resistant H pylori in Canada by searching MEDLINE from January 1980 to May 1999, as well as abstracts of the American Gastroenterology Association Digestive Disease Week, Canadian Digestive Disease Week and The European H pylori Study Group Meetings from January 1995 to May 1999. RESULTS: Eleven studies that estimated H pylori resistance to metronidazole resistance and nine that estimated resistance to clarithromycin in Canada were identified. Rates of resistance for metronidazole and clarithromycin varied from 11% to 48% and 0% to 12%, respectively. Studies that obtained their estimates using the E-test and those that did not clearly exclude patients who had undergone previous attempts at H pylori eradication had higher estimates of resistance, accounting for this variability in results. CONCLUSIONS: The prevalence of primary H pylori resistance in Canada appears to be 18% to 22% for metronidazole and less than 4% for clarithromycin. These rates appear to be consistent across the different regions studied in Canada, but many regions have not been studied.     

The trend of eradication rates of first-line triple therapy for Helicobacter pylori infection: single center experience for recent eight years]

BACKGROUND/AIMS: The prevalence of antibiotic resistance in Helicobacter pylori (H. pylori) infection has been reported to be increasing. However, the recent trend of eradication rates of H. pylori using first-line triple regimens has been rarely issued. Therefore, we aimed to determine the trend of H. pylori eradication rates in single center for recent eight years. METHODS: From January 1998 through October 2005, H. pylori eradication rates in 525 patients with H. pylori-positive peptic ulcer disease who received one-week triple regimens were retrospectively evaluated according to years, regimens, and ulcer locations. RESULTS: The overall H. pylori eradication rate was 78.7%. Yearly eradication rates from the year 1998 to 2005 were 83.7%, 80.4%, 81.4%, 78.8%, 75.3%, 77.6%, 78.9% and 77.6% consecutively by per-protocol analysis, However, no definite evidence of decreasing tendency of eradication rate was seen during the past eight years (p=0.419). Furthermore, there was no significant difference in the eradication rates according to the ulcer locations and regimens. CONCLUSIONS: Although it is found that there is no definite statistical evidence of decreasing trend for H. pylori eradication rate during past eight years, those for recent 5 years were lower than 80%, which suggests that we should scrutinize the trend of first-line H. pylori eradication rate, and concern for the expected lower rates in the near future.     

Poor efficacy of ranitidine bismuth citrate-based triple therapies for Helicobacter pylori eradication.

BACKGROUND: Helicobacter pylori eradication rates have tended to decrease recently possibly related with increasing antibiotic resistance. The present study investigated the efficacy of three different ranitidine bismuth citrate (RBC) based triple regimens in a population with high prevalence of H. pylori. METHODS: 300 consecutive H. pylori positive patients with non-ulcer dyspepsia were randomized into three regimens: (1) RBC 400 mg, amoxicillin 1000 mg and tetracycline 500 mg [RBC-AT], (2) RBC 400 mg, amoxicillin 1000 mg and clarithromycin 500 mg [RBC-AC], (3) RBC 400 mg, metronidazole 500 mg and tetracycline 500 mg [RBC-MT]. Tetracycline was given q.i.d, all other drugs were given b.i.d. for 14 days. Gastroscopy and (14)C-Urea breath test (UBT) were performed before enrollment and UBT only was repeated 6 weeks after the end of treatment. RESULTS: 274 patients completed the protocols. The overall 'intention to treat' and 'per protocol' H. pylori eradication rates in all subjects were 57.6% (95% CI: 52-63) and 63.1% (95% CI: 57-68), respectively. The eradication rates achieved in the groups (RBC-AT, RBC-AC and RBC-MT) were 64.4% (95% CI: 54-74), 66.2% (95% CI: 56-76), and 58.9% (95% CI: 49-68) on 'per protocol' analyses, respectively. There was no difference in eradication rates, compliance and major side effects between the groups. CONCLUSION: The current RBC-based H. pylori eradication therapy is not adequately effective.     

Institutional difference of antibiotic resistance of Helicobacter pylori strains in Korea

GOALS: This study was performed to evaluate whether the prevalence rates of primary antibiotic resistance in Helicobacter pylori isolates could be different between 2 institutions, which are located in the different areas in Korea, and to evaluate the effect of antibiotic resistance on the eradication rate of H. pylori. STUDY: H. pylori were isolated from gastric mucosal biopsy specimens obtained from 113 Koreans, who did not have any eradication history. The susceptibilities of the H. pylori isolates to amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, and moxifloxacin were examined according to the agar dilution method by 1 technician. RESULTS: All of these patients were treated with the same regimen, proton pump inhibitor-amoxicillin-clarithromycin triple therapy. There was a statistical difference in resistance to metronidazole, levofloxacin, and moxifloxacin among 6 antibiotics between 2 institutions located in Seoul and Gyeonggi province. The rates of eradication were 94.2% for the clarithromycin and amoxicillin-susceptible strains, and 42.8% for the amoxicillin-susceptible and clarithromycin-resistant strains. In contrast, eradication rate was 100% for the amoxicillin-resistant strains. CONCLUSIONS: These results show that there is institutional difference of antibiotic resistance of H. pylori, explaining the institutional difference of eradication rate of H. pylori. The resistance to clarithromycin seems to be an important determinant for the eradication by proton pump inhibitor triple therapy but resistance to amoxicillin does not have any effect.     

One-week ranitidine bismuth citrate versus colloidal bismuth subcitrate-based anti-Helicobacter triple therapy: a prospective randomized controlled trial

OBJECTIVE: The efficacy of 1 wk bismuth triple therapy is adversely influenced by the presence of metronidazole resistance. In vitro studies suggest that ranitidine bismuth citrate (RBC) plus metronidazole exhibit synergistic activity against metronidazole resistant strains of Helicobacter pylori (H. pylori). Whether this confers a superior clinical efficacy remains unproven. This study compared the efficacy of RBC-based triple therapy with bismuth triple therapy in eradication of H. pylori. METHODS: Patients with H. pylori-related ulcer disease or gastritis were randomized to receive either 400/mg of RBC twice daily plus 400/mg of metronidazole and 500/mg of tetracycline four times daily for 1 wk (RMT) or 120/mg of colloidal bismuth subcitrate, 400/mg of metronidazole, and 500/mg of tetracycline, all given four times daily for 1 wk (BMT). Metronidazole susceptibility was determined by the E-test and pretreatment resistance was defined as minimum inhibitory concentration > or = 32/mg/L. RESULTS: Of 100 consecutive patients randomized, two patients were lost to follow-up in each group. Forty-three of 85 (51%) H. pylori isolates were metronidazole resistant. Per-protocol cure rate for RMT and BMT was 40 of 41 (98%) and 37 of 44 (84%), respectively (p = 0.058). Intent-to-treat cure rate for RMT and BMT was 46 of 50 and 41 of 50, respectively (92% vs 82%, p = 0.23). A significantly higher eradication of metronidazole resistant H. pylori was observed in the RMT group (25 of 25, 100%) than in the BMT group (12 of 16, 75%), (p = 0.018). Side effects observed in the two treatment groups were comparable. CONCLUSIONS: One week of RBC triple therapy with metronidazole and tetracycline is an effective anti-Helicobacter therapy. This regimen is more appropriate in areas of high prevalence of metronidazole resistance.     

Resistance to metronidazole, clarithromycin and levofloxacin of Helicobacter pylori before and after clarithromycin-based therapy in Taiwan

Background and Aim:  Clarithromycin-based triple therapy has been commonly applied as the first-line therapy for Helicobacter pylori eradication. Levofloxacin could serve as an alternative in either first-line or second-line regimens. This study surveyed the prevalence of levofloxacin resistance of H. pylori isolates in naive patients and in patients with a failed clarithromycin-based triple therapy.
Methods:  The study collected the H. pylori isolates from 180 naive patients and 47 patients with a failed clarithromycin-based triple therapy. Their in vitro antimicrobial resistance was determined by E -test.
Results:  The naive H. pylori isolates had resistance rates for amoxicillin, levofloxacin, clarithromycin and metronidazole of 0%, 9.4%, 10.6% and 26.7%, respectively. An evolutional increase of the primary levofloxacin resistance was observed in isolates collected after 2004, as compared to isolates collected before 2004 (16.3% vs 3.2%, P  = 0.003). There was no evolutional increment of the primary clarithromycin resistance. The clarithromycin resistance elevated significantly after a failed clarithromycin-based triple therapy (78.7% vs 10.6%, P  < 0.001). The post-treatment isolates remained to have a levofloxacin resistance rate of near 17%, but the levofloxacin-resistant isolates were correlated with a higher incidence of metronidazole resistance ( P  = 0.023). No strain was found to be resistant to amoxicillin even after eradication failure.
Conclusion:  The levofloxacin resistance of naive H. pylori remains less than 10% in Taiwan. With relatively lower resistance to levofloxacin than to metronidazole of the H. pylori isolates collected after a failed clarithromycin-based therapy, proton pump inhibitor–levofloxacin–amoxicillin may be an alternative choice to serve as the second-line therapy.     

Development of Helicobacter pylori treatment: How do we manage antimicrobial resistance?

Helicobacter pylori(H. pylori) antimicrobial resistance is an urgent, global issue. In2017, the World Health Organization designated clarithromycin-resistant H.pylori as a high priority bacterium for antibiotic research and development. In addition to clarithromycin, resistance to metronidazole and fluoroquinolones has also increased worldwide. Recent international guidelines for management of H.pylori infection recommend bismuth or non-bismuth quadruple therapy for 14 d as a first-line treatment for H. pylori in areas of high clarithromycin and/or metronidazole resistance. Although these treatment regimens provide acceptable H. pylori eradication rates, the regimens used should not contribute to future resistance of H. pylori to antimicrobials. Moreover, these regimens can promote resistance, due to prolonged therapy with multiple antibiotics. A new strategy that can eradicate H. pylori as well as reduce the antibiotics used is required to prevent future antimicrobial resistance in H. pylori. Dual-therapy with vonoprazan and amoxicillin could be a breakthrough for H. pylori eradication in an era of growing antimicrobial resistance. This regimen may provide a satisfactory eradication rate of H. pylori and also minimize antimicrobial resistance due to single antibiotic use and the strong inhibitory effect of vonoprazan on gastric acid secretion.     

Risk factors for Helicobacter pylori resistance in the United States: the surveillance of H. pylori antimicrobial resistance partnership (SHARP) study, 1993-1999

BACKGROUND: Pretreatment antimicrobial resistance has an important impact on the efficacy of many Helicobacter pylori treatment regimens. OBJECTIVE: To estimate the prevalence of H. pylori resistance to antimicrobials in the United States, to characterize risk factors associated with H. pylori antimicrobial resistance, and to explore the association between drug utilization and antimicrobial resistance patterns over time. DESIGN: Meta-analysis using patient-level data. SETTING: 20 nationwide trials of H. pylori eradication. PATIENTS: 3624 men and women, each of whom contributed one isolate. MEASUREMENTS: Rates of H. pylori resistance to clarithromycin, metronidazole, and amoxicillin, according to geographic region, age, sex, study year, ethnicity, ulcer status, test method, and study. RESULTS: Overall resistance to clarithromycin, metronidazole, and amoxicillin was 10.1% (95% CI, 9.1% to 11.1% [360 of 3571 patients]), 36.9% (CI, 35.1% to 38.7% [1063 of 2883 patients]), and 1.4% (CI, 1.0% to 1.8% [48 of 3486 patients]), respectively. In multivariable analyses, multiple risk factors were associated with resistance to individual agents. Clarithromycin resistance was significantly associated with geographic region (P = 0.050), older age (P < 0.001), female sex (P < 0.001), inactive ulcer disease (P < 0.001), and study (P = 0.010). Metronidazole resistance was significantly associated with female sex (P < 0.001), earlier year of study enrollment (P = 0.036), Asian ethnicity (P < 0.001), use of an epsilometer test (P = 0.002), and study (P < 0.001). Amoxicillin resistance was low and was not significantly associated with any risk factor. In the 1990s, when rates for use of oral macrolides and metronidazole were relatively stable, clarithromycin resistance rates were stable and metronidazole resistance rates varied. CONCLUSIONS: Clinicians should consider risk factors for antimicrobial resistance when deciding which patients should have susceptibility testing and when choosing appropriate H. pylori treatments in the empirical setting.     

Usefulness of vonoprazan,a potassium ion-competitive acid blocker,for primary eradication of Helicobacter pylori

AIM To investigate usefulness of triple therapy with vonoprazan,a potassium ion-competitive acid blocker and antibiotics,for Helicobacter pylori(H.pylori) eradication.METHODS The H.pylori eradication rate was examined in 2507 patients(2055 undergoing primary eradication and 452 undergoing secondary eradication,excluding patients with subtotal gastrectomy) at the Japanese Red Cross Kyoto Daiichi Hospital from March 2013 to September 2015.For patients treated from March 2013 to February 2015,a proton pump inhibitor(PPI) was used to reduce acid secretion,while vonoprazan was used after March 2015.The success rates of the 2 regimens(PPI + amoxicillin + clarithromycin/metronidazole,or vonoprazan + amoxicillin + clarithromycin/metronidazole) were compared.RESULTS The success rate of primary H.pylori eradication was significantly higher in the vonoprazan group.When stratified by the underlying disease,a significant increase of the H.pylori eradication rate was observed in patients with chronic gastritis.A significantly lower H.pylori eradication rate was observed in younger patients compared to older patients in the PPI group,but there was no difference according to age in the vonoprazan group.On the otherhand,the success rate of secondary eradication was similar at approximately 90% in both groups.CONCLUSION Vonoprazan is very useful for primary eradication of H.pylori,and may become a first-line acid secretion inhibitor instead of PPIs.     

Evaluation of three different proton pump inhibitors with amoxicillin and metronidazole in retreatment for Helicobacter pylori infection

GOALS: We compared the eradication results of retreatment of eradication with proton pump inhibitor (PPI) plus amoxicillin and metronidazole for patients with Helicobacter pylori infection not eradicated by initial treatment with PPI plus amoxicillin and clarithromycin. BACKGROUND: In Japan, the guideline proposes that the use of metronidazole in a triple therapy containing PPI, PPI plus amoxicillin and metronidazole is desirable in retreatment. However, there are no reports comparing various retreatment using different PPIs. METHODS: After initial treatment failure with a PPI plus amoxicillin and clarithromycin, 169 patients were randomized to a PPI (rabeprazole, lansoprazole, or omeprazole) plus amoxicillin and metronidazole given b.i.d. for 7 days. RESULTS: Pretreatment susceptibility testing showed a high level of clarithromycin resistance (78%). The over all eradication rates were similar with the 3 PPIs, 91.1% range 90.1 to 91.4 with intention-to-treat analysis. The presence of metronidazole resistance reduced the eradication rate by approximately 40% (from 96.6% to 57.1%, P<0.05). CONCLUSIONS: In Japan, the combination of a PPI plus amoxicillin and metronidazole provide excellent eradication rates after initial treatment failure with a PPI plus amoxicillin and clarithromycin. The results with metronidazole resistant strains are less satisfactory and pretreatment susceptibility testing may become needed if the prevalence of metronidazole resistant H. pylori increase.     

Implications of antibiotic resistance in the management of Helicobacter pylori infection: Canadian Helicobacter Study Group.

Eradication of Helicobacter pylori from the gastric and duodenal mucosa is an important clinical goal in the treatment of infected patients with peptic ulcer disease and other H pylori-associated conditions. Although several oral drug combination regimens are associated with eradication rates of approximately 85% in controlled trials, the success rate in patients infected with a resistant strain of H pylori is closer to 75%. Resistance to metronidazole and clarithromycin, which are common components of combination treatment regimens, is of greatest concern. Reported rates of H pylori resistance to various antibiotics vary considerably. In Canada, the data documenting H pylori susceptibility are limited but suggest that resistance to these antibiotics varies geographically and within specific treatment groups. Although susceptibility testing is not a prerequisite for initial treatment of individual patients infected with H pylori, formal efforts to identify and monitor both the causes and prevalence of antibiotic resistance across Canada are a much needed step in the ongoing management of this important infection. Recommended treatment regimens may be useful, even for treating apparently resistant H pylori strains. However, it is important to understand the mechanisms of the development of resistant strains to manage patients with treatment failure better.     

Cost-Effectiveness of Treatment Regimens for the Eradication of Helicobacter pylori in Duodenal Ulcer

Background: Eradication of Helicobacter pylori with antimicrobials was recommended by a recent NIH consensus panel for all infected patients with peptic ulcer disease. The precise regimen that should be used for eradication of the infection remains uncertain because of the variety of regimens described, variable results with the regimens, and difficulties in predicting drug compliance outside clinical trials. Methods: A decision analysis tree was developed with three regimens that are widely used regimens for the eradication of H. pylori: 1 ) 2-wk triple drug therapy (metronidazole, bismuth, tetracycline with H2 receptor antagonist), 2) 2-wk omeprazole and amoxicillin, and 3) 2-wk omeprazole and clarithromycin. Traditional H2 receptor antagonist therapy was used for comparison. A 2-yr time period was chosen for study to allow sufficient time for relapse and to evaluate its effect on the treatment strategy. Probabilities for eradication, compliance, and metronidazole resistance were determined from published data, and assumptions were tested by sensitivity analysis. Results: Standard 2-wk triple drug therapy was the least expensive strategy ($720), and conventional H2 receptor antagonist therapy was the most expensive ($1791). Costs with 2-wk therapy with omeprazole and clarithromycin ($768) were lower than with omeprazole and amoxicillin ($1028). Conclusions. Treatment to eradicate H. pylori in infected patients with duodenal ulcer is a less expensive strategy than traditional therapy with H2 receptor antagonists. Triple drug therapy is the optimal regimen in areas where metronidazole resistance rates are <36% and compliance is >53%. Omeprazole and amoxicillin is not cost-effective unless eradication rates are greater than 74%. Dual drug therapy with omeprazole and clarithromycin is effective in regions where metronidazole resistance is high or where it is anticipated that there would be poor compliance with the more complicated triple drug therapy regimen.     

Low eradication rate of Helicobacter pylori with triple 7-14 days and quadriple therapy in Turkey

AIM:The eradication rate of Helicobacter pylori (H pylon) shows variation among countries and regimens of treatment.We aimed to study the eradication rates of different regimens in our region and some factors affecting the rate of eradication.METHODS:One hundred and sixty-four Hpylori positivepatients (68 males, 96 females; mean age:48&#177;12 years)with duodenal or gastric ulcer without a smoking history were included in the study. The patients were divided into three groups according to the treatment regimens. Omeprazole 20mg, clarithromycin 500mg, amoxicillin 1g were given twice daily for 1 week (Group I) and 2 weeks (Group Ⅱ).Patients in Group Ⅲ received bismuth subsitrate 300mg,tetracyline 500 mg and metronidazole 500mg four times daily in addition to Omeprazole 20mg twice daily.Two biopsies each before and after treatment were obtained from antrum and corpus, and histopathologically evaluated.Eradication was assumed to be successful if no Hpylorus was detected from four biopsy specimens taken after treatment. The effects of factors like age, sex, Hpyloridensity on antrum and corpus before treatment, the total Hpylori density, and the inflammation scores on the rate of Hpylori eradication were evaluated.RESULTS:The overall eradication rate was 42%. The rates in groups Ⅱ and Ⅲ were statistically higher than that in group I (P&lt;0.05). The rates of eradication were 24.5%,40.7% and 61.5% in groups Ⅰ, Ⅱ and Ⅲ, respectively. The eradication rate was negatively related to either corpus Hpylori density or total Hpyloridensity (P&lt;0.05).The median age was older in the group in which the eradication failed in comparison to that with successful eradication (55yr vs 39yr, P&lt;0.001). No correlation between sex and Hpylori eradication was found.CONCLUSION: Our rates of eradication were significantly lower when compared to those reported in literature.We believe that advanced age and high Hpyloridensity are negative predictive factors for the rate of Hpylorieradication.     

克拉霉素、甲硝唑和兰索拉唑联合治疗幽门螺杆菌感染的临床疗效观察

目的：本文报道克拉霉素与甲硝唑及兰索拉唑联合应用治疗ＨＰ阳性的十二指肠溃疡。方法：５９例符合条件的病人随机分成两个治疗组，其中３０例口服充拉霉素２５０ｍｇ，甲硝唑４００ｍｇ，兰索拉唑３０ｍｇ。另一组２９例口服克拉霉素５００ｍｇ，甲硝唑４００ｍｇ．兰索拉唑３０ｍｇ，用法均为每日２次，疗程１周，继而口服兰索拉唑３０ｍｇ，每日１次，共１周。疗程结束后１个月复查胃镜。结果：克拉霉素１０００ｍｇ组ＨＰ根除率及溃疡愈合率分别为９３．１％及８９．７％，稍高于克拉霉素５００ｍｇ组的７６．７％及８０．０％，但差异无显著性（Ｐ＞０．０５）。体外检测。克拉霉素ＨＰ耐药发生率仅４．８％，而甲硝唑ＨＰ耐药发生率则达３３．３％，且甲硝唑耐药对ＨＰ根除率有较大影响。两组病人副反应总发生率为１５．３％，克拉霉素两个剂量组间副反应发生率无明显差别，未发现严重副反应。病人依从性良好。结论：克拉霉素与甲硝唑及兰索拉唑合用１周疗法有较理想的溃疡愈合率与ＨＰ根除率；克拉霉素用量以每日１０００ｍｇ为佳。     

Antibiotic resistance of Helicobacter pylori isolated from Korean patients in 2003]

BACKGROUND/AIMS: Development of antibiotic resistance is a significant clinical problem in the eradication of H. pylori. To select an appropriate regimen, systematic information on antibiotic resistance is mandatory. Thus, we investigated the distribution of minimal inhibitory concentration (MIC) and evaluated the antibiotic resistance of H. pylori isolates from Korean patients in 2003. METHODS: The susceptibility of 65 isolates obtained in 2003 to amoxicillin, clarithromycin, metronidazole, tetracycline, azithromycin, and ciprofloxacin were determined by agar dilution method. RESULTS: Resistance rates of H. pylori to amoxicillin, clarithromycin, metronidazole, tetracycline, azithromycin, and ciprofloxacin were 18.5%, 13.8%, 66.2%, 12.3%, 32.3%, and 33.8%, respectively. Multi-drug resistance rate of H. pylori was 47.7%. Especially, 6.2% of the H. pylori isolates were resistant to both amoxicillin and clarithromycin. In addition, resistance to amoxicillin and clarithromycin resulted in decreasing tendency of the eradication efficacy for H. pylori. CONCLUSIONS: These results indicate that the antibiotics used for H. pylori eradication show high resistance rates in Korea. Furthermore, continuous surveillance of antibiotic susceptibilities should be needed and further increases in antibiotic resistance would require susceptibility testing before treatment to maximize the efficacy of H. pylori treatment.     

Antibiotic susceptibility of Helicobacter pylori in the Chinese population

AIM: To assess antibiotic susceptibility of Helicobacter pylori (H. pylori) strains to metronidazole, clarithromycin and tetracycline in the Chinese population, and to test the stability of antibiotic resistance in H. pylori 1 year after storage at -80 degrees C. METHODS: Fifty H. pylori strains isolated from patients with peptic ulcer disease were recovered from storage at -80 degrees C. Susceptibility of these strains to metronidazole, clarithromycin and tetracycline was determined by using validated disk diffusion tests, which was repeated 1 year after storage at -80 degrees C. The DNA profiles of each strain were determined by using the polymerase chain reaction-based-random amplified polymorphic DNA fingerprinting technique (PCR-RAPD). This was repeated if any change in antibiotic susceptibility pattern was noticed. RESULTS: The resistance rate was 50% to metronidazole and 8% to clarithromycin. None of the strains was resistant to tetracycline. A dual resistance to metronidazole and clarithromycin was demonstrated in three H. pylori strains. The antibiotic susceptibility test reproduced itself in 92% (36 of 39) of the strains 1 year later; the three strains with dual resistance exhibited susceptibility to both antibiotics. Variation in antibiotic susceptibility pattern in the three H. pylori strains was associated with change in the RAPD fingerprint. CONCLUSION: The prevalence of resistance in H. pylori is high to metronidazole but low to clarithromycin in the Chinese population. The disk diffusion test appears to be a simple and reliable test, while antibiotic resistance in some H. pylori strains may disappear after long-term storage at -80 degrees C.     

Primary antibiotic resistance and effectiveness of Helicobacter pylori triple therapy in ulcero-inflammatory pathologies of the upper digestive tract

OBJECTIVES: To determine firstly, the rates of primary antimicrobial resistance for Helicobacter pylori-associated upper-digestive lesions in relation to the success rate of triple therapy; and secondly, the performance of HpSA stool antigen detection test for control of eradication after treatment. METHODS: Prospective open study of 436 patients who underwent upper-digestive tract endoscopy with biopsies for histological examination and culture between January 1 and July 31, 2002 at a University hospital in Brussels, Belgium. The primary resistance to antibiotics of H. pylori isolates was determined by disc diffusion method. Seventy of 164 infected patients agreed to be included in the treatment study with standard triple therapy with amoxicillin + clarithromycin + omeprazole adjusted on the basis of antibiogram results. Control of eradication was tested by 14C-Urea breath test and H. pylori Stool Antigen test (HpSA test). RESULTS: Primary resistance to clarithromycin and metronidazole was observed in 3% and 31% of the isolates, respectively. No primary resistance to amoxicillin and tetracycline was observed. By intention to treat analysis, H. pylori was eradicated in 56 (80%) patients included in the therapeutic study. Three (4%) patients were lost to follow-up. The rate of eradication failure was 20% (14/70), included 11 cases documented by a positive control test (14C-Urea breath test). In comparison with 14C-Urea breath test, the H. pylori Stool Antigen test showed a sensitivity of 100%, a specificity of 91%, PPV of 69%, and NPV of 100%. CONCLUSION: Standard triple therapy achieved 80% bacterial eradication in this patient population with a low prevalence of H. pylori primary antibiotic resistance. Our data confirm that the H. pylori Stool Antigen test displays a diagnostic performance similar to the breath test for control of eradication.     

药敏试验在三联疗法根除幽门螺杆菌中的作用

背景：近年幽门螺杆菌（H．pylori）对硝基咪唑类和大环内酯类抗生素的耐药率快速增高,导致目前推荐的H．p？tori根除方案疗效降低。目的：观察体外实验中Hpylori对甲硝唑和克拉霉素的敏感性,评估药敏试验基础上的个体化治疗方案能否提高根除率。方法：对260例连续Hpylori阳性患者的内镜胃窦部活检标本行H．pylori培养和药敏试验。患者随机分为两组,A组（n=135）使用奥美托唑、甲硝唑和克拉霉素治疗10d,B组（n=125）在药敏试验的基础上接受10d个体化治疗。治疗结束1个月后．根据14C-尿素呼气试验结果评价根除率。结果：共248例患者（A组129例,B组119例）完成治疗和疗效评价,甲硝唑、克拉霉素单一和联合耐药率分别为31．0％、11．7％和3．6％。A组按方案（PP）分析和意向治疗（ITT）分析的H．pylori根除率分别为82．9％和79．3％,B组分别为98.3％和93．6％,B组根除率显著高于A组（P〈0．01）。结论：药敏试验基础上的个体化治疗可有效提高H．pylori的根除率。     

Pooled analysis of Helicobacter pylori eradication regimes in Asia

BACKGROUND AND AIMS: Differences in Helicobacter pylori strains and their resistance to antimicrobials between Asian and Western countries may affect the success in eradicating this bacterium. Our objective was to systematically review the regimens that have been tested in Asia. METHODS: Data on anti-H. pylori therapies reported from Asia in a large number of publications identified up to December 1998 were pooled into a few groups based on the combination of drugs used. A comparison of different groups was made by calculating the pooled eradication rates. RESULTS: Seventy-three studies with 134 treatment arms were reviewed. Pooled eradication rates of dual, triple and quadruple therapies were 61.0, 86.5 and 93.4%, respectively. Proton pump inhibitor (PPI)-based combinations were more widely used and effective, with overall eradication rates of 90.7% in triple therapy and 93.4% in quadruple therapy. Bismuth combined with tetracycline and metronidazole also showed a high eradication rate of 92.0%. CONCLUSIONS: Proton pump inhibitor-based triple therapy with either clarithromycin, amoxycillin or metronidazole was one of the most commonly used and effective anti-H. pylori triple therapy regimens in Asia. The classical triple therapy with a bismuth, tetracycline and metronidazole combination has a similar efficacy. The results of anti-H. pylori treatment in Asia are not different from those in Western countries.     

Helicobacter pylori antibiotic resistance in a Dutch region: trends over time

AIM: Most patients treated for H. pylori infection receive empirical therapy based on epidemiological data of antibiotic resistance. However, previous European studies indicate that resistance patterns may be changing. Therefore, the aim of this study was to investigate the prevalence of primary clarithromycin and/or metronidazole resistant H. pylori strains over a six-year period (1997-2002) in a regional hospital. METHODS: All patients visiting Slingeland Hospital in Doetinchem, the Netherlands between 1997 and 2002 with a positive H. pylori culture were included in this study. Susceptibility to metronidazole and clarithromycin was determined by disk diffusion. RESULTS: Of the 1355 patients with an H. pylori positive culture, 1127 did not have a history of H. pylori eradication, 58 did, and for 170 this information was not available. Mean rates of primary resistance to metronidazole and clarithromycin were 14.4% (162/1125) and 1.0% (11/1123), respectively. Primary metronidazole resistance was stable throughout the study period and primary clarithromycin resistance showed a decreasing trend. Patients of foreign descent and from secondary care had a higher chance of harbouring primary metronidazole-resistant H. pylori (adjusted OR (95% CI) 1.75 (1.1 to 2.8), and 1.60 (1.1 to 2.2), respectively). Patients with failed H. pylori eradication had a higher chance of harbouring metronidazole-resistant H. pylori (43 vs 14%, p<0.0001) and clarithromycin-resistantH. pylori (5.3 vs 1.0%, p=0.004) than untreated patients.CONCLUSION: Primary metronidazole resistance is stableat a low level, while primary clarithromycin resistance isvirtually absent in the eastern part of the Netherlands.Therefore, triple therapy with a proton pump inhibitor,clarithromycin and amoxicillin can remain the empiricaltreatment of choice in the Netherlands.