Antimicrobial Resistance Of Helicobacter Pylori Research Articles

Treatment failure of Helicobacter pylori in primary care: a retrospective cohort study.

Owing to increasing antibiotic resistance, the worldwide efficacy of Helicobacter pylori (HP) eradication treatment has decreased. To determine antimicrobial resistance of HP in primary care. Retrospective cohort study using real-world routine healthcare data from 80 general practices in the Netherlands. Patients with International Classification of Primary Care (ICPC) codes for gastric symptoms or Anatomical Therapeutic Chemical (ATC) codes for acid inhibition in the period 2010-2020 were selected. Main outcomes were antimicrobial resistance of HP, defined as the prescription of a second eradication treatment within 12 months, and clinical remission of gastric symptoms, defined as no usage of acid inhibition 1 year following eradication therapy. We identified 138 455 patients with gastric symptoms and/or acid inhibition use (mean age 57 years [standard deviation 18.2 years], 43% male). A total of 5224 (4%) patients received an HP eradication treatment. A second treatment was prescribed to 416 (8%) of those patients. From these, 380 patients received amoxicillin-clarithromycin, 16 amoxicillin-metronidazole, and 11 clarithromycin-metronidazole as first regimen and were considered antimicrobial resistant. We observed a 0.8% increment per year of patients requiring a second eradication treatment (P = 0.003, 95% confidence interval = 0.33 to 1.22). After successful eradication, 2329/4808 (48%) patients used acid inhibition compared with 355/416 (85%) patients following treatment failure (P<0.001). Antimicrobial treatment is not successful in almost one-tenth of HP infections in primary care after a first treatment containing clarithromycin and/or metronidazole. Although the treatment failure rate is not as high as reported in secondary care, the increasing trend is concerning and may require revision of the current guidelines.

Antimicrobial combinations against Helicobacter pylori including benzoxadiazol-based flavodoxin inhibitors: in vitro characterization.

The antimicrobial resistance of Helicobacter pylori (Hp) currently poses a threat to available treatment regimens. Developing antimicrobial drugs targeting new bacterial targets is crucial, and one such class of drugs includes Hp-flavodoxin (Hp-fld) inhibitors that target an essential metabolic pathway in Hp. Our study demonstrated that combining these new drugs with conventional antibiotics used for Hp infection treatment prevented the regrowth observed with drugs used alone. Hp-fld inhibitors show promise as new drugs to be incorporated into the treatment of Hp infection, potentially reducing the development of resistance and shortening the treatment duration.

Antimicrobial-Resistance Profile of Helicobacter pylori, Obtained from Endoscopic Patients in Bahir Dar, North West Ethiopia.

Antimicrobial resistance for Helicobacter pylori infection is a highly emerging problem throughout the world to treat gastric-associated diseases. People living in developing countries are more likely to acquire a Helicobacter pylori infection and less likely to gate treatment after infection due to poverty. Therefore, the current study was aimed at determining the magnitude and antibiotic-resistance profile of Helicobacter pylori isolated from patients who underwent endoscopic examination. A cross-sectional study was conducted from January to May 2019 at endoscopy service-providing health facilities that are found in Bahir Dar, Ethiopia (Gamby teaching general hospital, Kidane Mihret specialty higher clinic, and Eyasta specialty higher clinic). Data were collected using a pretested, structured questionnaire. Antibiotic susceptibility of Helicobacter pylori isolates from gastric biopsies was determined. Data were analyzed using SPSS version 23. The 17.8% proportion of Helicobacter pylori was isolated from 135 endoscopy-examined patients (24/135). The majority of isolates (71% of 17/24) were from males, while only 29% of 7/24) were from females. Antimicrobial-resistance of Helicobacter pylori was high to all commonly prescribed antibiotics: amoxicillin and metronidazole (91.7%), clarithromycin and ciprofloxacin (66.7% each), and tetracycline (37.5%). Helicobacter pylori isolates from the current study participants were rather low in number. But the highest antibiotic-resistance profile of Helicobacter pylori was observed. Therefore, these findings alarmingly indicate that routine antimicrobial susceptibility testing against Helicobacter pylori isolates is crucial for better patient management.

Susceptibility-guided vs. empirical 10-day quadruple treatment for Helicobacter pylori-infected patients: A prospective clinical trial of first-line therapy.

BackgroundThe increasing antimicrobial resistance of Helicobacter pylori (H. pylori) has resulted in a fall in cure rates. We aimed to assess the effectiveness of first-line susceptibility-guided therapy and furazolidone-based quadruple therapy for H. pylori-infected patients.MethodsSubjects with H. pylori-infection were randomly assigned to either 10-day susceptibility-guided treatment or empiric treatment in a 2:1 ratio. Susceptibility-guided therapy was based on susceptibility to clarithromycin, and patients with susceptible strains received clarithromycin 500 mg twice daily and otherwise minocycline 100 mg twice a day was administered. Patients in the empiric therapy group was treated with furazolidone 100 mg twice a day. During treatment, all patients were given esomeprazole 20 mg twice daily, colloidal bismuth pectin 200 mg twice daily, and amoxicillin 1 g twice daily.ResultsA total of 248 patients were screened and 201 were finally included. Empiric and susceptibility-guided regimens were both successful with per-protocol eradication rates of 90.5% (57/63) vs. 88.5% (108/122) (p = 0.685) and intent-to-treat eradication rates of 85.1% (57/67) vs. 80.6% (108/134) (p = 0.435). No significant difference in eradication rates were observed among the furazolidone group, clarithromycin group and minocycline group.ConclusionBoth susceptibility-guided therapy and quadruple therapy containing furazolidone can achieve good eradication rates. For population with a high rate of resistance, quadruple therapy containing furazolidone and bismuth may be a more practical choice for first-line treatment.

Therapeutic Guidelines and Antimicrobial Resistance of Helicobacter Pylori in Patients with Peptic Ulcer at Tertiary Care Hospitals of Rawalpindi and Islamabad

Objective: The purpose of this study was to investigate the prevalence of antibiotic resistance among Helicobacter pylori isolates obtained from patients suffering from peptic ulcer disease in Rawalpindi and Islamabad, Pakistan, and to propose a novel anti-H. pylori therapy strategy for use in these locations. Methodology: A total of 132 H. pylori from the patients suffering with peptic ulcer disease were reported for clinical treatment in institutions in the twin Cities that provide tertiary care. Antibiotics such as ciprofloxacin, clarithromycin, amoxycillin, metronidazole, and tetracycline were tested on the isolates to determine their levels of susceptibility to these drugs. The Epsilometer test, often known as the E-test, is a quantitative disc diffusion method that is used to determine antibiotic sensitivity. This test was utilised for the purpose of verifying isolates. Results: The overall rate of resistance among H. pylori was found to be 27.9% for amoxycillin, 38.9% for clarithromycin, and 73.6% for metronidazole. 47 out of 132 isolates exhibited multiple drug resistance, with metronidazole, clarithromycin, and amoxycillin showing the highest frequency of two, three, and four drug resistance patterns. Ciprofloxacin had a low level of tetracycline resistance, ranging from 1.2 to 4%, whereas metronidazole resistance was substantial. In the population of Pakistan, the frequency of H. pylori resistance to metronidazole is quite high, whereas it is moderate in response to clarithromycin and amoxycillin, and low in response to ciprofloxacin and tetracycline. The rates of resistance to clarithromycin and amoxycilin were higher in Rawalpindi than they were in Islamabad. It is imperative, for the sake of the public's health, that Pakistan make an adjustment to its policy regarding antibiotics, one that will permit the use of antibiotic rotation in the treatment of H. pylori. Keywords: Peptic ulcer, Helicobacter pylori, antibiotic susceptibility.

Correlation Analysis Among Genotype Resistance, Phenotype Resistance, and Eradication Effect After Resistance-Guided Quadruple Therapies in Refractory Helicobacter pylori Infections.

ObjectivesThe antimicrobial resistance of Helicobacter pylori (H. pylori) in most countries and regions has increased significantly. It has not been fully confirmed whether the detection of H. pylori resistance gene mutation can replace antibiotic drug sensitivity test to guide the clinical personalized treatment. The objective of this study was to assess and compare the efficacy of different antimicrobial resistance-guided quadruple therapies in refractory H. pylori-infected individuals who had undergone unsuccessful prior eradication treatments.MethodsFrom January 2019 to February 2020, genotypic and phenotypic resistances were determined by polymerase chain reaction (PCR), whole genome sequencing (WGS) and broth microdilution test, respectively, in 39 H. pylori-infected patients who have failed eradication for at least twice. The patients were retreated with bismuth quadruple therapy for 14 days according to individual antibiotic resistance results. Eradication status was determined by the 13C-urea breath test.ResultsThe overall eradication rate was 79.5% (31/39, 95% CI 64.2–89.5%) in the intention-to-treat (ITT) analysis and 88.6% (31/35, 95% CI 73.5–96.1%) in the per- protocol analysis (PP) analysis. The presence of amoxicillin resistance (OR, 15.60; 95% CI, 1.34–182.09; p = 0.028), female sex (OR, 12.50; 95% CI, 1.10–142.31; p = 0.042) and no less than 3 prior eradication treatments (OR, 20.25; 95% CI, 1.67–245.44; p = 0.018), but not the methods for guiding therapy (p > 0.05) were associated with treatment failure. Resistance-guided therapy achieved eradication rates of more than 80% in these patients. The eradication rate of H. pylori in the phenotypic resistance-guided group was correlated well with genotype resistance-guided groups, including PCR and WGS.ConclusionCulture or molecular method guiding therapy can enable personalized, promise salvage treatments, and achieve comparably high eradication rates in patients with refractory H. pylori infection. The detection of H. pylori resistance mutations has a good clinical application prospect.Protocol Study Register[clinicaltrials.gov], identifier [ChiCTR1800020009].

Antimicrobial resistance of Helicobacter pylori in West Flanders – Belgium: an observational cross-sectional study

ABSTRACT Objectives Data on Helicobacter pylori (HP) resistance in Belgium are largely based on the patient population of Brussels and Wallonia. Notably Brussels harbours a large proportion of patients with a migration background which might not be representative for other parts of the country. Methods An observational cross-sectional study was performed in the province of West Flanders, Belgium for collecting gastric biopsies to examine the resistance of HP. The study population consisted of patients who underwent a gastroduodenoscopy for any medically indicated purpose. Rapid urease testing (RUT) was performed on all biopsies and cultures were only started if the RUT showed positive. Results 512 patients participated of whom 495 were eligible for analysis: 438 in first line testing and 57 in second line. The growth of HP was successful in 88.9% (n = 88/99) of which 52.3% (n = 46/88) resulted in an antibiogram. The resistance rate in first line was based on 37 succeeded antibiograms and showed 13.5% resistance for clarithromycin (95% confidence interval; 2.5% to 24.5%); 29.7% for metronidazole; 29.7% for levofloxacin; 11.4% for rifampicin; 2.7% for amoxicillin and 0% for tetracycline. Conclusion The primary clarithromycin resistance rate of HP could still be slightly under 15% in West Flanders, Belgium. This might implicate a clarithromycin-based triple therapy is an option for first line empiric eradication in this region according to the Maastricht V/Florence consensus although conclusions must be interpreted with caution due to the rather small sample size. Further testing in Flanders is recommended to confirm these results.

The increasing antimicrobial resistance of Helicobacter pylori in Iran: A systematic review and meta-analysis.

Antimicrobial resistance of Helicobacter pylori can result in eradication failure. Metadata on the antimicrobial resistance of H pylori in Iran could help to formulate H pylori eradication strategies in Iran. A systematic review was performed after searching in MEDLINE, Scopus, Embase, Web of Science, and the Cochrane Library. A meta-analysis was performed, and a comparison of the rates between children and adults; time periods (1999-2010, 2011-2016, 2017-2019); and the methods used was carried out. A total of 66 studies investigating 5936 H pylori isolates were analyzed. The weighted pooled resistance (WPR) rates were as follows: clarithromycin 21% (95% CI 16-26), metronidazole 62% (95% 57-67), clarithromycin in combination with metronidazole 16% (95% CI 10-23), ciprofloxacin 24% (95% CI 15-33), levofloxacin 18% (95% CI 9-30), erythromycin 29% (95% CI 12-50), furazolidone 13% (95% CI 4-27), tetracycline 8% (95% CI 5-13), and amoxicillin 15% (95% CI 9-22). During the three time periods, there was an increased resistance to amoxicillin, clarithromycin, ciprofloxacin, furazolidone, and tetracycline (P˂.05). Furazolidone and a clarithromycin/metronidazole combination had the higher resistance rates in children (P˂.05). An increasing rate of resistance to amoxicillin, clarithromycin, ciprofloxacin, furazolidone, and tetracycline in Iranian H pylori isolates was identified. In children, the resistance to furazolidone and a combination of clarithromycin and metronidazole is higher compared to adults. As a stable, high resistance to metronidazole was found in children and adults in all Iranian provinces, we suggest that metronidazole should not be included in the Iranian H pylori eradication scheme.

Genetic Antibiotic Resistance of Helicobacter pylori in South-Eastern Romania.

Helicobacter pylori infection is very common worldwide, and it is associated with an important gastric pathology. Treatment of this infection is difficult and consists of the combination of two or three antibiotics. However, the rate of resistance to treatment is high. Antimicrobial resistance of Helicobacter pylori is based on its cultivation in the laboratory and testing of phenotypic susceptibility, a time-consuming, laborious method. This study aimed to detect the genetic resistance to antibiotics of Helicobacter pylori in the south-eastern region of Romania. Ninety patients with positive rapid urease test gastric biopsy samples were tested. Genetic resistance to antibiotics (fluoroquinolone and clarithromycin) was tested by GenoType HelicoDR kit (Hain Lifescience GmbH, Germany). Clarithromycin resistance mutations were detected in 20% of patients, the commonest mutation in our study beeing A2147G (associated with high level of clarithromycin resistance and lower cure rates). Fluoroquinolones resistance mutations were detected in 30% of patients, and the most common mutations were D91N, D91G, and N87K. There was no correlation with patients gender or age, with the exception of fluoroquinolone resistance, which was detected more frequently in females. Conclusions. Clarithromycin and fluoroquinolone resistance of Helicobacter pylori is moderately high in our study. There is a need for monitoring Helicobacter resistance patterns in Romania to provide data that can guide empirical treatment. This is the first published study on the genetic resistance of Helicobacter pylori in Romania.

Primary and secondary antibiotic resistance of Helicobacter pylori in Korea from 2003 to 2018.

Antimicrobial resistance of Helicobacter pylori (Hpylori) affects the efficacy of eradication therapy. The aim of this study was to estimate the prevalence of primary and secondary resistance of Hpylori isolates to antibiotics in Korea. The present study was performed from 2003 to 2018. Primary resistance was evaluated in 591 patients without any history of eradication and secondary resistance in 149 patients from whom Helicobacter pylori was cultured after failure of eradication. A minimal inhibitory concentration test was performed for amoxicillin, clarithromycin, metronidazole, tetracycline, levofloxacin, and rifabutin using the agar dilution method. An increase in the primary resistance rate was found in clarithromycin (P<.001), metronidazole (P<.001), and both levofloxacin (P<.001) during the study period. The primary resistance rates of amoxicillin and tetracycline were low and stable during the study period. The secondary resistance rate significantly increased in metronidazole and levofloxacin (P=.022 and .039, respectively). The primary and secondary resistance rates of clarithromycin, metronidazole, and levofloxacin for Helicobacter pylori in Korea were high and increased over time. However, the primary and secondary resistance rates of amoxicillin and tetracycline were low and stable over time. These results will help in selecting effective eradication regimens of Hpylori in Korea in the future.

The Study of the Antimicrobial Resistance of Helicobacter Pylori in Shandong Province

The Study of the Antimicrobial Resistance of Helicobacter Pylori in Shandong Province

Increasing antimicrobial resistance to clarithromycin and metronidazole in pediatric Helicobacter pylori infection in southern Taiwan: A comparison between two decades.

Antimicrobial resistance of Helicobacter pylori reduces the eradication rate. This study aimed to investigate changes in antimicrobial susceptibility of Hpylori isolated from children in Taiwan in the past two decades. This study enrolled children receiving esophagogastroduodenoscopy for upper gastrointestinal diseases in a national tertiary referring hospital from 1998 to 2018. Hpylori infection was diagnosed by culture. The minimal inhibitory concentrations (MICs) of antibiotics were tested using the E test. The antibiotic resistance rates and MICs of amoxicillin, clarithromycin, metronidazole, levofloxacin, and tetracycline were compared between 1998-2008 and 2009-2018. A total of 70 Helicobacter pylori isolates (29 from 1998 to 2008 and 41 from 2009 to 2018) were identified. The esophagogastroduodenoscopy findings included duodenal ulcers (n=31), gastric ulcers (n=9), and gastritis (n=30). The overall antimicrobial resistance rates of clarithromycin and metronidazole were 22.9% and 21.4%, respectively. The dual resistance rate of clarithromycin and metronidazole was 10%. Resistance rates of levofloxacin and amoxicillin were 8.3% and 2.9%, respectively. None of the isolates were resistant to tetracycline. Compared with the isolates from 1998 to 2008, those from 2009 to 2018 had higher MICs and resistance rates of clarithromycin (26.8% vs 17.2%, P=0.35) and metronidazole (26.8% vs 13.8%, P=0.19), but not levofloxacin (9.8% vs 5.3%, P=1.0) or coresistance to clarithromycin and metronidazole (12.2% vs 6.9%, P=0.69). The antimicrobial resistance rates of pediatric Hpylori isolates to clarithromycin and metronidazole increased during the past decade. The selection of antimicrobial agents other than clarithromycin and metronidazole is crucial to increase pediatric Hpylori eradication rates.

Antimicrobial resistance of Helicobacter pylori in Germany, 2015 to 2018

ObjectivesNational and international guidelines recommend empiric first-line treatments of individuals infected with Helicobacter pylori without prior antimicrobial susceptibility testing. For this reason, knowledge of primary resistance to first-line antibiotics such as clarithromycin is essential. We assessed the primary resistance of H. pylori in Germany to key antibiotics by molecular genetic methods and evaluated risk factors for the development of resistance. MethodsGastric tissue samples of 1851 yet treatment-naïve H. pylori-positive patients were examined with real-time PCR or PCR and Sanger sequencing for mutations conferring resistance to clarithromycin, levofloxacin and tetracycline. Clinical and epidemiological data were documented and univariable and multivariable logistic regression analyses were conducted. ResultsOverall primary resistances were 11.3% (210/1851) to clarithromycin, and 13.4% (201/1497) to levofloxacin; resistance to tetracycline (2.5%, 38/1497) was as low as combined resistance to clarithromycin/levofloxacin (2.6%, 39/1497). Female sex and prior antimicrobial therapies owing to unrelated bacterial infections were risk factors for clarithromycin resistance (adjusted OR (aOR) 2.3, 95% CI 1.6–3.4; and 2.6, 95% CI 1.5–4.5, respectively); older age was associated with levofloxacin resistance (aOR for those ≥65 years compared with those 18–35 years: 6.6, 95% CI 3.1–14.2). ConclusionsClarithromycin might still be recommended in first-line eradication therapies in yet untreated patients, but as nearly every tenth patient may carry clarithromycin-resistant H. pylori it may be advisable to rule out resistance ahead of treatment by carrying out susceptibility testing or prescribing an alternative therapy.

Antimicrobial Resistance of Helicobacter pylori Isolates in Korea

This corrects the article "Antimicrobial Resistance of Helicobacter pylori Isolates in Korea" on page 82.

Prospective multicentre clinical study on inter- and intrapatient genetic variability for antimicrobial resistance of Helicobacter pylori

ObjectivesWe report on a large prospective, multicentre clinical investigation on inter- and intrapatient genetic variability for antimicrobial resistance of Helicobacter pylori. MethodsTherapy-naive patients (n = 2004) who had undergone routine diagnostic gastroscopy were prospectively included from all geographic regions of Austria. Gastric biopsy samples were collected separately from antrum and corpus. Samples were analysed by histopathology and real-time PCR for genotypic resistance to clarithromycin and quinolones. Clinical and demographic information was analysed in relation to resistance patterns. ResultsH. pylori infection was detected in 514 (26%) of 2004 patients by histopathology and confirmed in 465 (90%) of 514 patients by real-time PCR. PCR results were discordant for antrum and corpus in 27 (5%) of 514 patients, indicating inhomogeneous infections. Clarithromycin resistance rates were 17% (77/448) and 19% (84/455), and quinolone resistance rates were 12% (37/310) and 10% (32/334) in antrum and corpus samples, respectively. Combination of test results per patient yielded resistance rates of 21% (98/465) and 13% (50/383) for clarithromycin and quinolones, respectively. Overall, infection with both sensitive and resistant H. pylori was detected in 65 (14%) of 465 patients. ConclusionsAnatomically inhomogeneous infection with different, multiple H. pylori strains is common. Prospective clinical study design, collection of samples from multiple sites and microbiologic methods that allow the detection of coinfections are mandatory for collection of reliable data on antimicrobial resistance patterns in representative patient populations. (ClinicalTrials.gov identifier: NCT02925091).

Prospective, multicenter clinical trial on inter- and intra-patient genetic variability for antimicrobial resistance of Helicobacter pylori

Prospective, multicenter clinical trial on inter- and intra-patient genetic variability for antimicrobial resistance of Helicobacter pylori

Helicobacter pylori resistance to antibiotics in 2014 in France detected by phenotypic and genotypic methods

A large survey of antimicrobial resistance of Helicobacter pylori was performed in France in 2014: 984 patients were enrolled by 75 gastroenterologists all over the country. Among the 783 patients who had never received eradication treatment before, 266 (33.9%) were H. pylori positive. The strains showed a high rate of clarithromycin resistance (22.2%), moderate rate of resistance to levofloxacin (15.4%) and high rate of resistance to metronidazole (45.9%). In all, 187 patients had received previous treatment, of which 115 were H. pylori positive with very high resistance to clarithromycin (73.9%) and metronidazole (78.3%). None of the patients receiving PYLERA (Bismuth salt-Tetracycline HCl-Metronidazole) proton-pump inhibitor developed resistance to tetracycline. A real-time PCR applied to gastric biopsy specimens detected all the cases that were positive by culture as well as 30 additional cases. A good correlation was found between the clarithromycin resistance detected by phenotypic methods and the associated mutations for clarithromycin resistance, which has continued to increase in the last decade but at a lower rate than previously observed.

Evaluation of antimicrobial resistance of Helicobacter pylori in the last 15 years in West Poland.

Increasing resistance to drugs represents a serious problem in treatment of infections with Helicobacter pylori, providing cause of frequent therapeutic failures. Present study aimed at analysis of changes in resistance of H. pylori to antibiotics in West Poland within the recent 15 years. 108 strains of H. pylori were analysed, isolated from gastric mucosa of adult patients. Group 1 involved 66 strains isolated in years of 1998/1999. Group 2 comprised 42 isolates obtained in years of 2013/2014. Susceptibility to amoxicillin (AMX), clarithromycin (CL), tetracycline (TC) and metronidazole (MTZ) was determined by E-test (AB Biodisc). All strains on both studied groups were susceptible to AMX. In group 1 all strains proved to be susceptible to TC, while 9% and 36% of tested strains were resistant to CL and MTZ, respectively. By contrast, in group 2, 31% and 83% of strains were resistant to CL and MTZ, respectively. In parallel, 14% strains were found to be resistant to TC (according to EUCAST interpretations). In West Poland, within recent 15 years a dramatic increase was noted in H. pylori strains resistant to metronidazole. In parallel, a significant increase was noted in proportion of strains resistant to clarithromycin.

Prospective multicentre study on antimicrobial resistance of Helicobacter pylori in Germany.

Antimicrobial resistance of Helicobacter pylori endangers the successful eradication of the bacteria. The aim of this prospective surveillance study (ResiNet) is to continuously keep antimicrobial resistance of H. pylori in Germany under surveillance and to identify risk factors for its development. From July 2001 until December 2012, we tested the antimicrobial susceptibility of H. pylori strains isolated from 1651 prospectively enrolled patients. We analysed clinical and epidemiological data and identified risk factors for the development of resistance. Average primary resistances were 29.4% for metronidazole, 6.7% for clarithromycin and 3.1% for both antimicrobials. Prior unsuccessful eradication treatments, female sex and country or continent of origin were identified as independent risk factors for development of resistance. H. pylori-positive patients without prior eradication therapy can be treated empirically; antimicrobial susceptibility testing is recommended in previously unsuccessfully treated patients and in patients who have received antimicrobial chemotherapies due to unrelated bacterial infections.

GenoType HelicoDR test in the determination of antimicrobial resistance of Helicobacter pylori in Korea

Objective. Antimicrobial resistance of Helicobacter pylori is most important factor in eradication success. GenoType HelicoDR test has been developed for rapid detection of antimicrobial resistance. The present study evaluated the clinical usefulness of GenoType HelicoDR test in Korea. Materials and methods. To detect 23S rRNA for clarithromycin resistance and gyrA mutations for fluoroquinolone resistance, both DNA sequencing after minimal inhibitory test (MIC) and GenoType HelicoDR test were performed in H. pylori isolates from the gastric mucosa of 101 patients. The eradication results of clarithromycin and moxifloxacin-containing triple therapy were evaluated by the 23S rRNA and gyrA mutations. Results. For 42 isolates with A2143G mutation by GenoType HelicoDR, 83.3% (35/42) of concordance rate was estimated with DNA sequencing method and 85.7% (36/42) for MIC test. For 43 isolates with N87K mutation by GenoType HelicoDR, 71.1% (31/43) of concordance rate was estimated with DNA sequencing and 88.4% (38/43) for MIC test. The sensitivity and specificity of GenoType HelicoDR test in determination of 23S rRNA mutation were 94.9% and 87.1%, and those of gyrA 98.2% and 80.0%. The sensitivity and specificity of GenoType HelicoDR test in determination of clarithromycin resistance based on MIC test were 55.0% and 80.0%, for fluoroquinolone 74.4% and 70.0%. Conclusion. GenoType HelicoDR test is useful to determine mutations responsible for clarithromycin or fluoroquinolone-containing eradication failure but has a limitation for the clinical applicability in determination of resistance.