Clarithromycin Resistance Rate Research Articles

Vonoprazan Dual or Triple Therapy Versus Bismuth-Quadruple Therapy as First-Line Therapy for Helicobacter pylori Infection: A Three-Arm, Randomized Clinical Trial.

We compared efficacy of vonoprazan-dual or triple therapies and bismuth-quadruple therapy for treatment-naive Helicobacter pylori (HP) infection in Southern China, where primary resistance rates of clarithromycin and levofloxacin are >30%. This was an investigator-initiated, three-arm, randomized clinical trial in Southern China. Between March 2022 and August 2023, treatment-naïve HP-infected adults were randomly assigned to receive one of three 14-day regimens (1:1:1 ratio): vonoprazan-dual (VA-dual; vonoprazan 20 mg twice daily and amoxicillin 1 g thrice daily), vonoprazan-triple (VAC-triple; vonoprazan 20 mg/amoxicillin 1 g/clarithromycin 500 mg twice daily), or bismuth-quadruple therapy containing bismuth, esomeprazole, tetracycline, and metronidazole. Primary outcome was noninferiority in HP eradication, evaluated by UBT 4-6 weeks post-treatment by intention-to-treat (ITT) and per-protocol (PP) analysis (based on subjects who completed 14-day treatment and rechecked UBT). Bonferroni-adjusted p-value of <0.017 was used to determine statistical significance. A total of 298 subjects (mean age: 35.7 ± 8.4 years; male: 134 [45.0%]; VC-dual: 100, VAC-triple: 98, bismuth-quadruple: 100) were enrolled, and 292 (98.0%) had UBT rechecked. ITT analysis showed that both VA-dual (eradication rate of 96.0%) and VAC-triple therapies (95.9%) were noninferior to bismuth-quadruple therapy (92.0%) (difference: 4.0%, 95% CI: -2.9% to 11.5%, p < 0.001; and 3.9%, 95% CI: -3.1% to 11.5%, p < 0.001, respectively). PP analysis also revealed noninferiority (96.7% or 96.7% vs. 97.4%, with difference: -2.9% and -2.9%, p = 0.009 and 0.010, respectively). The frequency of adverse events was 39.0%, 56.1%, and 71.0% in VA-dual, VAC-triple, and bismuth-quadruple therapies, respectively. VA-dual and VA-triple therapies are highly effective and noninferior to bismuth-quadruple therapy in Southern China. Given the lower adverse effects and fewer antibiotic use, VA-dual therapy is the preferred first-line treatment for HP infection. Chinese Clinical Trial Registry (No. ChiCTR2200056375). Registered on February 4, 2022, https://www.chictr.org.cn/showproj.aspx?proj=14131.

Efficacy and safety of tegoprazan- and rabeprazole-based concomitant therapies for Helicobacter pylori infection: Real-world evidence.

Tegoprazan, a novel potassium-competitive acid blocker, has been approved for Helicobacter pylori eradication in Korea. We compared the efficacy and safety of tegoprazan- and rabeprazole-based concomitant therapies for H.pylori eradication in real-world clinical practice. We retrospectively analyzed data from patients with H.pylori infection treated with tegoprazan- or rabeprazole-based concomitant therapies. The primary endpoint was H.pylori eradication rate. The secondary endpoint was adverse events. Among the 1474 included patients, 620 and 854 received tegoprazan- and rabeprazole-based concomitant therapies, respectively. Intention-to-treat analysis showed no significant difference in the eradication rates between the tegoprazan- and rabeprazole-based concomitant therapy groups (74.7% [95% confidence interval [CI], 71.1-78.0%] vs 72.7% [95% CI, 69.7-75.6%], P=0.400). Per-protocol analysis also demonstrated similar eradication rates for the groups (tegoprazan vs rabeprazole: 88.0% [95% CI, 85.0-90.6%] vs 85.9% [95% CI, 83.2-88.3%], P=0.288). Although the overall adverse event rate did not differ between groups (tegoprazan vs rabeprazole, 39.2% vs 40.6%, P=0.578), abdominal discomfort was less frequent in the tegoprazan group than in the rabeprazole group (1.3 vs 4.8%, P=0.001). Tegoprazan- and rabeprazole-based concomitant therapies for H.pylori eradication showed comparable efficacy and overall safety. The effect of tegoprazan on dose increases or other regimens, such as bismuth-containing quadruple therapy, should be further evaluated, because the efficacy of tegoprazan-based concomitant therapy may be suboptimal in regions where the clarithromycin resistance rate is high.

Bismuth-based quadruple therapy versus standard triple therapy for the eradication of Helicobacter pylori in Belgium: a multicentre, non-blinded randomized, prospective study.

Helicobacter pylori (Hp) infection predisposes to malignant and non-malignant diseases warranting eradication. In Belgium, resistance rates for clarithromycin demonstrate regional variations making the use of standard triple therapy (STT) borderline acceptable. According to a recent Belgian survey, STT and bismuth-based quadruple therapy (BQT), are equally frequent prescribed as first line treatment for treatment naïve Hp positive patients. This study aims to evaluate the eradication rates (ER) of BQT versus STT. Multicentre, non-blinded randomized, prospective study comparing ER in treatment-naïve Hp positive patients. ER were compared by intention to treat (ITT) and per protocol (PP) analysis. Overall 250 patients were included (STT 126, BQT 124). Seventeen patients were lost to follow-up (6,8%). No significant difference in ER between BQT and STT was observed in ITT (73% vs 68%, p= 0,54) neither in PP analysis (81% vs 75%, p= 0,33). Side effects and endoscopic findings were comparable between groups. Post-hoc analysis showed no differences according to gender or site allocation. The numerical advantage of BQT did not translate in a significant improvement of ER when compared with STT. These results question the cost-effectiveness of BQT, while confirming the suboptimal eradication rates on STT. A nationwide monitoring of resistance patterns, maximal investments in treatment adherence as well as a detailed follow-up of the changing treatment landscape are mandatory to continuously optimise Hp ER in Belgium.

Impact of primary duodenogastric reflux and Helicobacter pylori infection on gastritis and antibiotic resistance in children

To investigate the risk factors for Helicobacter pylori (HP) infection in children with primary duodenogastric reflux (DGR) and its impact on gastritis and antibioticresistance. A retrospective analysis was performed on the clinical data of 2 190 children who underwent upper gastrointestinal endoscopy in Wuxi Children's Hospital from January 2019 to February 2022, among whom 308 children were diagnosed with primary DGR. According to the presence or absence of HP infection, the children were classified to HP infection group (53 children) and non-HP infection group (255 children). The risk factors for HP infection and its impact on the incidence rate and severity of gastritis were analyzed. According to the presence or absence of primary DGR, 331 children with HP infection were classified to primary DGR group (29 children) and non-primary DGR group (302 children), and then the impact of primary DGR with HP infection on antibiotic resistance was analyzed. The HP infection group had a significantly higher age than the non-HP infection group (P<0.05), and there was a significant difference in the age distribution between the two groups (P<0.05), while there were no significant differences in the incidence rate and severity of gastritis between the two groups (P>0.05). The multivariate logistic regression analysis showed that older age was a risk factor for HP infection in children with DGR (P<0.05). Drug sensitivity test showed that there were no significant differences in the single and combined resistance rates of metronidazole, clarithromycin, and levofloxacin between the primary DGR group and the non-primary DGR group (P>0.05). Older age is closely associated with HP infection in children with DGR. Primary DGR with HP infection has no significant impact on gastritis and antibiotic resistance in children.

Comparison of Helicobacter pylori eradication rates between 7 and 14 days of tailored therapy according to clarithromycin resistance test: A randomized, multicenter, non-inferiority study.

Recently, a simple tailored therapy based on clarithromycin resistance has been implemented as Helicobacter pylori (H. pylori) eradication therapy. Nonetheless, despite the tailored therapy and frequent adverse events, studies on treatment period are lacking. This study aimed to compare the H. pylori eradication rates of 7-day and 14-day tailored therapy regimens according to clarithromycin resistance. This multicenter, prospective, randomized, noninferiority trial enrolled H. pylori-positive patients who were randomly assigned to 7-day and 14-day regimen groups, depending on the presence or absence of clarithromycin resistance by 23S rRNA gene point mutations. Standard triple therapy (STT) (20 mg rabeprazole, 1 g amoxicillin, and 500 mg clarithromycin twice daily) or bismuth quadruple therapy (BQT) (20 mg rabeprazole twice daily, 500 mg metronidazole thrice daily, 120 mg bismuth four times daily, and 500 mg tetracycline four times daily) was assigned by clarithromycin resistance. Eradication rates and adverse events were evaluated. A total of 314 and 278 patients were included in the intention-to-treat (ITT) and per-protocol (PP) analyses, respectively; however, 31 patients were lost to follow-up, whereas five patients violated the protocol. Both the 7-day and 14-day regimens showed similar eradication rates in the ITT (7-day vs. 14-day: 78.3% vs. 78.3%, p > 0.99) and PP (87.9% vs. 89.1%, p = 0.851) analyses. Non-inferiority was confirmed (p < 0.025). A subgroup analysis according to clarithromycin resistance (clarithromycin resistance rate: 28.7%) revealed no significant difference in eradication rates between the 7-day and 14-day STT (90.0% vs. 90.1%, p > 0.99) and BQT (82.5% vs. 86.5%, p = 0.757). Furthermore, adverse events did not significantly differ between the two groups. The 7-day triple and quadruple therapy according to clarithromycin resistance showed similar eradication rates, as compared to the 14-day therapy.

Role of MIC levels and 23S rRNA mutation sites to clarithromycin in 14-day clarithromycin bismuth quadruple therapy for Helicobacter pylori eradication: A prospective trial in Beijing

BackgroundRising clarithromycin resistance undermines Helicobacter pylori (H. pylori) treatment efficacy. We aimed to determine clarithromycin's minimum inhibitory concentration (MIC) levels and identify specific mutation sites in the 23S ribosomal subunit (23S rRNA) that predict treatment outcomes in a 14-day regimen of clarithromycin bismuth quadruple therapy (amoxicillin 1g, clarithromycin 500 mg, rabeprazole 10 mg, and colloidal bismuth pectin 200 mg). Materials and methodsWe included adult H. pylori patients who hadn't previously undergone clarithromycin-based treatment, either as initial or rescue therapy. Exclusions were made for penicillin allergy, recent use of related medications, severe illnesses, or inability to cooperate. Patients underwent a 14-day clarithromycin bismuth quadruple therapy. Gastric mucosa specimens were obtained during endoscopy before eradication. MIC against amoxicillin and clarithromycin was determined using the E-test method. The receiver operating characteristic (ROC) curve helped to find the optimal clarithromycin resistance MIC breakpoint. Genetic sequences of H. pylori 23S rRNA were identified through Sanger Sequencing. (ChiCTR2200061476) ResultsOut of 196 patients recruited, 92 met the inclusion criteria for the per-protocol (PP) population. The overall intention-to-treat (ITT) eradication rate was 80.00 % (84/105), while the modified intention-to-treat (MITT) and PP eradication rates were 90.32 % (84/93) and 91.30 % (84/92) respectively. No amoxicillin resistance was observed, but clarithromycin resistance rates were 36.19 % (38/105), 35.48 % (33/93), and 34.78 % (33/92) in the ITT, MITT, and PP populations respectively. Compared with the traditional clarithromycin resistance breakpoint of 0.25 μg/mL, a MIC threshold of 12 μg/mL predicted better eradication. Among 173 mutations on 152 sites in the 23S rRNA gene, only the 2143A > G mutation could predict eradication outcomes (p < 0.000). ConclusionsInterpretation of elevated MIC values is crucial in susceptibility testing, rather than a binary "susceptible" or "resistant" classification. The 2143A > G mutation has limited specificity in predicting eradication outcomes, necessitating further investigation into additional mutation sites associated with clarithromycin resistance.

High antibiotic resistance rates in Helicobacter pylori strains in Turkey over 20 years: implications for gastric disease treatment.

Helicobacter pylori (Hp) eradication therapy is crucial for preventing the development of gastritis, peptic ulcers, and gastric cancer. An increase in resistance against antibiotics used in the eradication of Hp is remarkable. This meta-analysis aims to examine the resistance rates of Hp strains isolated in Turkey over the last 20 years against clarithromycin (CLR), metronidazole (MTZ), levofloxacin (LVX), tetracycline (TET), and amoxicillin (AMX) antibiotics. Literature search was carried out in electronic databases, by searching articles published in Turkish and English with the keywords ' helicobacter pylori ' or 'Hp' and 'antibiotic resistance' and 'Turkey'. That meta-analysis was carried out using random-effect model. First, the 20-year period data between 2002 and 2021 in Turkey were planned to be analyzed. As a second stage, the period between 2002 and 2011 was classified as Group 1, and the period between 2012 and 2021 as Group 2 for analysis, with the objective of revealing the 10-year temporal variation in antibiotic resistance rates. In gastric biopsy specimens, 34 data from 29 studies were included in the analysis. Between 2002-2021, CLR resistance rate was 30.9% (95% CI: 25.9-36.2) in 2615 Hp strains. Specifically, in Group 1, the CLR resistance rate was 31% in 1912 strains, and in Group 2, it was 30.7% in 703 strains. The MTZ resistance rate was found to be 31.9% (95% CI: 19.8-45.4) in 789 strains, with rates of 21.5% in Group 1 and 46.6% in Group 2. The overall LVX resistance rate was 25.6%, with rates of 26.9% in Group 1 and 24.8% in Group 2. The 20-year TET resistance rate was 0.8%, with 1.50% in Group 1 and 0.2% in Group 2. The overall AMX resistance rate was 2.9%, 3.8% between 2002-2011, and 1.4% between 2012-2021. Hp strains in Turkey exhibit high resistance rates due to frequent use of CLR, MTZ, and LVX antibiotics. However, a significant decrease has been observed in TET and AMX resistance to Hp in the last 10 years. Considering the CLR resistance rate surpasses 20%, we suggest reconsidering the use of conventional triple drug therapy as a first-line treatment. Instead, we recommend bismuth-containing quadruple therapy or sequential therapies (without bismuth) for first-line treatment, given the lower rates of TET and AMX resistance. Regimens containing a combination of AMX, CLR, and MTZ should be given priority in second-line therapy. Finally, in centers offering culture and antibiogram opportunities, regulating the Hp eradication treatment based on the antibiogram results is obviously more appropriate.

Prevalence of Helicobacter pylori infection and clarithromycin resistance rate from 2015 to 2018 using the laboratory information system of the Seegene Medical Foundation in Korea: a repeated cross-sectional study

Background: Numerous studies have examined the prevalence of Helicobacter pylori infection and clarithromycin (CLA) resistance rate of H. pylori. However, in South Korea, there is a lack of research analyzing specimens from local clinics and hospitals using molecular methods. This study aimed to assess the prevalence of H. pylori infection and CLA resistance across sex and age groups, as well as to explore regional variations in CLA resistance and its characteristics. Methods: Data from a laboratory information system from 2015 to 2018 were retrospectively analyzed to determine the prevalence of H. pylori infection and CLA resistance rate. The 23S ribosomal RNA genes of H. pylori were analyzed using a dual priming oligonucleotide-based multiplex polymerase chain reaction method. Results: The overall prevalence of H. pylori infection was 50.5%(12,000/23,773), with a significantly higher prevalence among males (53.5%) than females (47.0%). The CLA resistance rate was 28.3%, with a significantly higher rate among females (34.9%) than males (23.8%). Age group analysis revealed that the highest prevalence of H. pylori infection was among individuals in their 40s, whereas the highest CLA resistance rate was observed among those in their 60s. The CLA resistance rate exhibited an upward trend and varied among patients based on their place of residence, and A2143G mutation was the most prevalent across all regions. Conclusion: The prevalence of H. pylori infection and CLA resistance rate in Korea remain high and vary according to sex, age, and region. To effectively eradicate H. pylori, it is crucial to periodically monitor regional CLA resistance patterns and conduct CLA susceptibility testing before prescription.

Antibiotic resistance in Helicobacter pylori among children and adolescents in East Asia: A systematic review and meta-analysis.

In East Asia, Helicobacter pylori ( H. pylori ) infection and related diseases are common, primarily during childhood and adolescence. The rates of primary antibiotic resistance in H. pylori among East Asian children and adolescents have not been extensively explored; few relevant systematic reviews or meta-analyses have been conducted. We evaluated the rates of antibiotic resistance in H. pylori among East Asian children and adolescents, with the goal of facilitating individualized treatment recommendations. We searched PubMed, Embase, and the Cochrane Library for studies in any language published up to February 2023 that explored antibiotic resistance in H. pylori among East Asian children and adolescents. We used MeSH and non-MeSH terms related to the topic, including terms related to children, adolescents, antibiotic resistance, H. pylori , and nations or regions. Additionally, we reviewed the reference lists of relevant articles. Studies that matched our strict predefined eligibility criteria were included in the screening process. Using established assessment methods, we evaluated the quality of the included studies. We identified 15 observational studies involving 4831 H. pylori isolates, all published between 2001 and 2022. There was substantial primary antibiotic resistance in H. pylori isolates from East Asian children and adolescents. The rates of primary resistance were 51% (95% confidence interval [CI]: 40-62%) for metronidazole; 37% (95% CI: 20-53%) for clarithromycin; 19% (95% CI: 11-28%) for levofloxacin; and less than 3% each for amoxicillin, tetracycline, and furazolidone. Subgroup analysis revealed a prominent increase in metronidazole resistance over time. Clarithromycin and levofloxacin resistance rates fluctuated between 2005 and 2015, then remained stable; other antibiotic resistance rates were generally stable. Metronidazole, clarithromycin, and levofloxacin resistance rates were significantly higher in the Chinese mainland than in other East Asian regions. The rates of dual and multiple antibiotic resistance were 28% (95% CI: 21-36%) and 10% (95% CI: 7-14%), highlighting the potential for diverse resistance patterns. H. pylori isolates from East Asian children and adolescents exhibit high levels of metronidazole and clarithromycin resistance, particularly in the Chinese mainland. The non-negligible rates of dual and multiple resistance highlight the complexity of this problem. PROSPERO, No. CRD42023402510.

Success of susceptibility-guided eradication of Helicobacter pylori in a region with high secondary clarithromycin and levofloxacin resistance rates.

Resistance to clarithromycin (CLA) and levofloxacin (LFX) of Helicobacter pylori (H. pylori) is increasing in severity, and successful eradication is essential. Presently, the eradication success rate has greatly declined, leaving a large number of patients with previous treatment histories. To investigate secondary resistance rates, explore risk factors for antibiotic resistance, and assess the efficacy of susceptibility-guided therapy. We recruited 154 subjects positive for Urea Breath Test who attended The First Affiliated Hospital of China Medical University between July 2022 and April 2023. Participants underwent a string test after an overnight fast. The gastric juice was obtained and transferred to vials containing storage solution. Subsequently, DNA extraction and the specific DNA amplification were performed using quantitative polymerase chain reaction (qPCR). Demographic information was also analyzed as part of the study. Based on these results, the participants were administered susceptibility-guided treatment. Efficacy was compared with that of the empiric treatment group. A total of 132 individuals tested positive for the H. pylori ureA gene by qPCR technique. CLA resistance rate reached a high level of 82.6% (n = 109), LFX resistance rate was 69.7% (n = 92) and dual resistance was 62.1% (n = 82). Gastric symptoms [odds ratio (OR) = 2.782; 95% confidence interval (95%CI): 1.076-7.194; P = 0.035] and rural residence (OR = 5.152; 95%CI: 1.407-18.861; P = 0.013) were independent risk factors for secondary resistance to CLA and LFX, respectively. A total of 102 and 100 individuals received susceptibility-guided therapies and empiric treatment, respectively. The antibiotic susceptibility-guided treatment and empiric treatment groups achieved successful eradication rates of 75.5% (77/102) and 59.0% (59/411) by the intention-to-treat (ITT) analysis and 90.6% (77/85) and 70.2% (59/84) by the per-protocol (PP) analysis, respectively. The eradication rates of these two treatment strategies were significantly different in both ITT (P = 0.001) and PP (P = 0.012) analyses. H. pylori presented high secondary resistance rates to CLA and LFX. For patients with previous treatment failures, treatments should be guided by antibiotic susceptibility tests or regional antibiotic resistance profile.

Antibiotic resistance of Helicobacter pylori in Nanjing, China: a cross-section study from 2018 to 2023.

The increasing prevalence of antibiotic resistance in cases of Helicobacter pylori (H. pylori) infection has emerged as a significant global issue. This study offers a comprehensive examination of the alterations in drug resistance exhibited by H. pylori in the Nanjing region of China during the preceding five years. Another important objective is to investigate the influence of levofloxacin medication history on genotypic and phenotypic resistance. This research screened 4277 individuals diagnosed with H. pylori infection between April 2018 and May 2023. The phenotype and genotypic resistance were evaluated using the Kirby-Bauer disk diffusion and PCR method. The most recent primary resistance rates for metronidazole, clarithromycin, levofloxacin, amoxicillin, furazolidone, and tetracycline were recorded at 77.23% (2385/3088), 37.24% (1150/3088), 27.72% (856/3088), 0.52% (16/3088), 0.19% (6/3088), and 0.06% (2/3088), respectively. For the recent five years, we observed a notable upsurge in the rate of metronidazole resistance and a slight elevation of clarithromycin and levofloxacin resistance. The documented resistance rates to single-drug, dual-drug, triple-drug, and quadruple-drug regimens were 35.39%, 28.32%, 25.72%, and 0.21%, respectively. The prevalence of multidrug-resistant strains escalated, rising from 37.96% in 2018 to 66.22% in 2023. The rate of phenotypic and genotypic resistance rate (57.10% and 65.57%) observed in strains obtained from patients without a levofloxacin treatment history was significantly lower than the rate in strains obtained from those with a history of levofloxacin treatment (88.73% and 94.74%). The prevailing gyrA mutations were primarily N87K (52.35%, 345/659), accompanied by D91N (13.96%, 92/659), and closely followed by D87G (10.77%, 71/659). For gyrA mutations, the 91-amino acid mutants exhibit a higher likelihood of discrepancies between phenotypic and genotypic resistance than the 87-amino acid mutants. The extent of antibiotic resistance within H. pylori remains substantial within the Nanjing region. If levofloxacin proves ineffective in eradicating H. pylori during the initial treatment, its use in subsequent treatments is discouraged. The employment of levofloxacin resistance genotype testing can partially substitute conventional antibiotic sensitivity testing. Notably, predicting phenotypic resistance of levofloxacin through PCR requires more attention to the mutation type of gyrA to improve prediction accuracy.

Pattern of Primary Resistance of Helicobacter pylori to Clarithromycin among Pediatric Patients from North-Eastern Romania.

Helicobacter pylori antibiotic resistance has increased worldwide and affects the effectiveness of current therapies. The recommended first-line empiric treatment should be tailored to the local clarithromycin resistance rate. This study aimed to determine the pediatric patient profile and rate of clarithromycin resistance for patients diagnosed with Helicobacter pylori by gastric biopsy. We studied 84 positive gastric samples for Helicobacter pylori. Positive results were confirmed by a rapid urease test and histopathological examination, with the type of gastritis established according to the Sydney System. Gastric biopsy samples were stored in RNA saver. Clarithromycin resistance was determined by a real-time polymerase chain reaction-based molecular assay after RNA-DNA extraction. Of the 84 biopsy samples analyzed, 35 (41.6%) were resistant to clarithromycin. Clarithromycin resistance was found mainly in girls (80%) with a mean age of 15 years (range 6-17 years). The history of prior exposure to clarithromycin was 91.6%. The concordance between the histopathological examination and the PCR test was 100%. One in 2.4 children infected with Helicobacter pylori had a strain resistant to clarithromycin. This resistant strain may be a reason for treatment failure in Romanian children, yet this is uninvestigated. The high rate of bacterial resistance to this antibiotic among children indicates the need for susceptibility testing before therapy.

The use of non-invasive stool tests for verification of Helicobacter pylori eradication and clarithromycin resistance.

Clarithromycin resistance of Helicobacter pylori (H. pylori) represents a major challenge in eradication therapy. In this study, we assessed if non-invasive stool tests can be used to verify successful H. pylori eradication and determine clarithromycin resistance. In this prospective study, patients undergoing urea breath testing (UBT) for confirmation of H. pylori eradication were asked to collect the stool as both a dry fecal sample and fecal immunochemical test (FIT). Stool H. pylori antigen testing (SAT) was performed on these samples and assessed for its accuracy in eradication verification. Type and duration of antibiotic treatment were retrospectively collected from patient records and compared with clarithromycin resistance determined by PCR of stool samples. H. pylori eradication information was available for a total of 145 patients (42.7% male, median age: 51.2). Successful eradication was achieved in 68.1% of patients. SAT on FIT samples had similar accuracy for eradication assessment compared to dry fecal samples, 72.1% [95% CI 61.4-81.2] versus 72.2% [95% CI 60.9-81.7]. Clarithromycin resistance rate was 13.4%. H. pylori antigen testing on FIT stool samples to verify H. pylori eradication is feasible and has similar accuracy as H. pylori antigen testing on dry stool samples. Dry stool, but not FIT, was suitable for non-invasive identification of H. pylori clarithromycin resistance by rt-PCR personalizing antibiotic treatment strategies without the need for invasive diagnostics is desirable, as the cure rate of first-line empirical H. pylori treatment remains low.

Phenotype and genotype analysis for Helicobacter pylori antibiotic resistance in outpatients: a retrospective study.

To investigate the antibiotic resistance of Helicobacter pylori (H. pylori) in outpatients and to explore the consistency between genotype and phenotype of H. pylori antibiotic resistance. A retrospective study on outpatients screened with urea breath test for H. pylori infection in Nanjing First Hospital from April 2018 to January 2022. Patients who tested positive underwent a consented upper endoscopy, and the H. pylori infection was confirmed by rapid urease test (RUT) and H. pylori culture. For antibiotic resistance phenotype analysis, the H. pylori strains isolated from gastric biopsy were tested for antibiotic resistance phenotype by the Kirby-Bauer disk diffusion test. In addition, the antibiotic resistance genotype of isolated H. pylori was tested with a real-time polymerase chain reaction. A total of 4,399 patients underwent H. pylori infection screening, and 3,306 H. pylori strains were isolated. The antibiotic resistance phenotype test revealed that the resistance rates of metronidazole (MTZ), clarithromycin (CLR), levofloxacin (LEV), amoxicillin (AMX), furazolidone (FR), and tetracycline (TE) were 74.58%, 48.61%, 34.83%, 0.76%, 0.27%, and 0.09%, respectively. Additionally, the antibiotic resistance genotype test revealed that rdxA gene mutation A610G (92.96%), A91G (92.95%), C92A (93.00%), and G392A (95.07%) were predominant in H. pylori with MTZ resistance; 23S rRNA gene mutation A2143G (86.47%) occurred in most H. pylori with CLR resistance; and gyrA gene mutation 87Ile/Lys/Tyr/Arg (97.32%) and 91Asn/Gly/Tyr (90.61%) were the most popular mutations in strains with LEV resistance. The phenotypic resistance and genotypic resistance to CLR (kappa value = 0.824) and LEV (kappa value = 0.895) were in good agreement. The history of eradication with MTZ, CLR, LEV, and AMX was correlated with H. pylori resistance. In short, this study demonstrated that drug resistance of H. pylori was mainly to MTZ, CLR, and LEV in local outpatients. Three drugs can be selected for increased MICs (Minimum Inhibitory Concentration) via single chromosomal mutations. In addition, the genotype could be used to predict the phenotypic H. pylori resistance to CLR and LEV. IMPORTANCE Helicobacter pylori is a key bacterium that causes stomach diseases. There was a high prevalence of H. pylori in the Chinese population. We analyzed the resistance phenotype and genotype characteristics of H. pylori in 4,399 outpatients at the First Hospital of Nanjing, China. We found a higher resistance rate to metronidazole (MTZ) , clarithromycin (CLR), and levofloxacin (LEV), and the genotype could be used to predict the phenotypic H. pylori resistance to CLR and LEV. This study provides information on H. pylori infection and also provides guidance for clinical doctors' drug treatment.

Refractory Helicobacter pylori infection in Australia: updated multicentre antimicrobial resistance.

Helicobacter pylori infection is responsible for considerable morbidity and mortality worldwide and eradication rates are falling globally because of increasing antimicrobial resistance. However, there is a paucity of local data to guide the choice of eradication therapy in Australia. This study aimed to evaluate current Australian rates of H. pylori antibiotic resistance in patients who had failed prior eradication therapy. A retrospective analysis of routine culture and antibiotic susceptibility data from two pathology laboratories servicing multiple tertiary referral hospitals in Western Australia (WA) and South Australia (SA), between 2018 and 2022, was performed. Rates of antimicrobial resistance and prevalence of multiresistant isolates in both SA and WA were calculated and comparison of temporal trends and differences between the two states was conducted. A total of 796 H. pylori isolates revealed a clarithromycin resistance rate of 82%, metronidazole 68%, amoxicillin 4.4% and tetracycline 0.5%. Resistance to levofloxacin was observed in 22% and rifampicin 14%. Rates of resistance to clarithromycin were lower in SA compared with WA (incidence rate ratio [IRR]: 0.69, P = 0.0001). Multiresistant isolates were discovered in 63% of patients, with lower rates in SA compared with WA (IRR: 0.74, P = 0.002). This first multicentre, multistate study of H. pylori resistance in Australian patients exposed to prior therapy demonstrated high rates of antimicrobial resistance, including levofloxacin (>20%). This raises concern about recommending levofloxacin in empirical second-line therapies. Increased monitoring and awareness of current H. pylori resistance rates in Australia are needed to guide local eradication practices.

A comprehensive study of Helicobacter pylori infection: molecular analysis, antibacterial susceptibility, and histopathological examination.

Helicobacter pylori is a pathogen associated with gastroduodenal diseases. This study aimed; (i) to investigate H. pylori presence by invasive tests in adult dyspeptic patients, (ii) to determine antibiotic susceptibility and genotypic characteristics of the H. pylori isolates, and (iii) to investigate the relationship between the H. pylori genotypes and the histopathological findings. In this cross-sectional study, gastric biopsy samples from 208 adult dyspeptic patients were used for culture, tissue Polymerase Chain Reaction (PCR), and histopathological analysis. Antibiotic susceptibility of the H. pylori isolates was analyzed by gradient method. Analysis of the virulence genes was performed by monoplex PCR. Genetic profiles (from A to H) were created based on the virulence genes presence. Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR) was used for the genotyping of the H. pylori isolates. The mean age of the patients was 46 (± 15) years and 128 (61.5%) of them were female. H. pylori positivity was detected by culture, tissue PCR and histopathological examination in 59 (28.4%), 114 (54.8%) and 81 (38.9%) patients, respectively. The overall prevalence of H. pylori was found to be 63% (131/208). All H. pylori isolates were susceptible to tetracycline and amoxicillin. The resistance rates for metronidazole, clarithromycin, levofloxacin, and rifampicin were 67.2%, 27.9%, 34.4% and 13.11%, respectively. Multi drug resistance (MDR) was detected at the rate of 45.9% (28/61). While the most common virulence gene was cagA (93.44%), the least common was vacAm1 (23%). The predominant genetic profile was profile A (47.5%). ERIC-PCR results revealed a total of 26 different patterns. A high prevalence of H. pylori was detected in adult dyspeptic patients as in developing countries. It was observed significant genotypic heterogeneity and virulence gene diversity within the isolates. A considerable resistance rate detected against antibiotics such as clarithromycin, metronidazole, and levofloxacin, which are frequently used in the eradication of H. pylori, should be taken into consideration when creating regional empirical treatment regimens.

Prevalence of Helicobacter pylori Antibiotic Resistance in Patients Enrolled in Guangzhou, China.

Helicobacter pylori (H. pylori) infection is a high-risk factor for the occurrence of gastric cancer. The quadruple therapy has been widely used as the first-line treatment for H. pylori in China. However, the increasing resistance rate to antibiotics has become a major challenge in the treatment of H. pylori. Therefore, there is an urgent need for rapid and cost-effective detection of antibiotic resistance to different antibiotics. To evaluate the prevalence of H. pylori antibiotic resistance in Guangzhou and the diagnostic performance of DOB value of 13C UBT in predicting antibiotic resistance. In this retrospective study, we collected data from 193 H. pylori culture-positive patients in Guangzhou on their DOB values and resistance to antibiotics. We analyzed the antibiotic resistance rate of commonly used antibiotics in quadruple therapy, and the diagnostic efficacy of DOB value was evaluated. The resistance rates of clarithromycin (CLA) and levofloxacin (LEV) were 46.1% and 44.0%, respectively. In the age group under 40, the resistance rate of LEV was lower than that of CLA. However, the diagnostic efficacy of DOB value was found to be low and it could not serve as an independent indicator for diagnosing resistance to CLA and LEV. The high resistance rates of CLA and LEV in H. pylori patients in Guangzhou indicate the urgent need for effective detection methods. The DOB value is not a direct indicator of antibiotic resistance to CLA and LEV. Therefore, it is important to use a combination of diagnostic methods to accurately assess antibiotic resistance in H. pylori infection.

Survey of Helicobacter pylori levofloxacin and clarithromycin resistance rates and drug resistance genes in Ningxia, 2020-2022

Objective: To explore the rate of Helicobacter pylori (Hp) resistance to levofloxacin and clarithromycin and the common mutation patterns of resistance genes in Ningxia, and to assess the concordance between phenotypic resistance and genotypic resistance. Methods: Cross-sectional study. Patients diagnosed with Hp infection in 14 hospitals in Ningxia region from February 2020 to May 2022 were retrospectively selected. Hp strains were isolated from gastric biopsy specimens of Hp-infected patients and subjected to phenotypic drug sensitivity testing and detection of resistance genes to analyze the rate of Hp resistance to levofloxacin and clarithromycin and the common mutation patterns of resistance genes in Ningxia region; and the concordance rate and Kappa concordance test were used to assess the concordance between phenotypic resistance and genotypic resistance. Results: A total of 1 942 Hp strains were isolated and cultured, and among the infections, 1 069 cases (55.0%) were male and 873 cases (45.0%) were female, aged (50.0±12.5) years (15-86 years). The rates of Hp resistance to levofloxacin and clarithromycin in Ningxia were 42.1% (818/1 942) and 40.1% (779/1 942), respectively, and the rate of dual resistance to both was 22.8% (443/1 942). The rate of resistance to levofloxacin and clarithromycin of Hp strains from female patients was higher than in male patients (levofloxacin: 50.4%(440/873) vs 35.4%(378/1 069); clarithromycin: 44.4%(388/873) vs 36.6%(391/1 069), both P<0.001). Among the GyrA gene mutations associated with levofloxacin resistance, the differences in mutation rate of amino acid at positions 87 and 91 were statistically significant in both drug-resistant and sensitive strains(both P<0.001), except for Asn87Thr. Hp strains were statistically significant for levofloxacin (Kappa=0.834, P<0.001) and clarithromycin (Kappa=0.829, P<0.001) had good concordance in resistance at the phenotypic and genotypic levels. Conclusion: The resistance of Hp to levofloxacin and clarithromycin in Ningxia region is severe, and there is good consistency between genotypic and phenotypic resistance.

Surveillance of Helicobacter pylori resistance over 22 Years (2000-2021) in Northern Spain

Helicobacter pylori gastritis is considered an infectious disease, regardless of symptoms and stage of disease. Most consensus documents recommend empirical therapy based on local antimicrobial susceptibility patterns. We aimed to provide clinically useful information about primary and secondary antimicrobial resistance to antimicrobials commonly prescribed for H. pylori. Overall, 31,406 gastroduodenal biopsies and 2,641 string tests from patients over 15 years of age were plated on selective media, isolating H. pylori in 36.7% of biopsies and 50.7% of string tests. Susceptibility testing could be performed in 96.6% (12,399/12,835) of H. pylori isolates. Polymerase chain reaction (PCR) was also used to detect H. pylori and its resistance to clarithromycin, providing susceptibility data for 112 patients with negative culture results. Resistance to amoxicillin and tetracycline was unusual (0.6% and 0.2%, respectively). Rates of primary resistance to clarithromycin and metronidazole remained steady over the 22-year study period, at around 14% for clarithromycin and 30% for metronidazole, while primary resistance to levofloxacin tripled (from 7.6% in 2000 to 21.7% in 2021, P < 0.001) and increased with patient age. Notably, 1.8% of isolates were multiresistant to clarithromycin, metronidazole, and levofloxacin. Overall, secondary resistance rates were higher (P < 0.0001) than primary resistance rates for clarithromycin (42.5% vs 14.1%), metronidazole (40.9% vs 32%), and levofloxacin (21.5% vs 17.1%). Determination of susceptibility for H. pylori by culture and/or PCR in patients undergoing endoscopy could facilitate the implementation of tailored therapy and guide the choice of empirical therapy when susceptibility testing cannot be performed, potentially helping limit the emergence of antimicrobial resistance.

The Helicobacter pylori single nucleotide polymorphisms SNPs associated with multiple therapy resistance in Colombia.

The eradication of Helicobacter pylori (H. pylori) using multiple therapies is used as a prevention strategy. However, its efficacy has been compromised by the emergence of single nucleotide polymorphisms in genes associated with H. pylori's resistance to multiple antibiotics. To estimate antibiotic resistance rates associated with mutations in H. pylori genes in the high-cancer-risk population in Colombia, we included 166 H. pylori whole genome sequences from a cohort of individuals with a high risk of gastric cancer. By using the reference strain ATCC 26695, we identified mutations in specific genes to evaluate resistance rates for different antibiotics: 23S rRNA for clarithromycin, 16S rRNA for tetracycline, pbp1A for amoxicillin, gyrA for levofloxacin, and rdxA for metronidazole. The phylogenomic analysis was conducted using the core genome consisting of 1,594 genes of H. pylori-ATCC 26695. Our findings revealed that the resistance rate of H. pylori to clarithromycin was 3.62%, primarily associated with mutations A2143G and A2142G in the 23S rRNA gene. For tetracycline, the resistance rate was 7.23%, with mutations A926G, A926T, and A928C observed in the 16S rRNA gene. Amoxicillin resistance was found in 25.9% of cases, with observed mutations in the pbp1A gene, including T556S, T593, R649K, R656P, and R656H. In the gyrA gene, mutations N87K, N87I, D91G, D91N, and D91Y were identified, resulting in a resistance rate of 12.04% to levofloxacin. The most common mutations in the rdxA gene associated with metronidazole resistance were a stop codon, and mutations at D59N and D59S, resulting in a resistance rate of 99.3%. The high resistance rate of H. pylori to metronidazole indicated that this drug should be excluded from the eradication therapy. However, the resistance rates for tetracycline and clarithromycin did not exceed the established resistance threshold in Colombia. The increased resistance rate of H. pylori to levofloxacin and amoxicillin may partially explain the observed therapeutic failures in Colombia. The phylogenomic tree showed that the H. pylori isolate belongs to its own lineage (hspColombia). These findings offer valuable insights to enhance the characterization of treatment protocols for the specific H. pylori lineage (hspColombia) at the local level.