Broad spectrum resistance in Helicobacter pylori isolated from gastric biopsies of patients with dyspepsia in Cameroon and efflux-mediated multiresistance detection in MDR isolates

Abstract Background Antibiotic resistance is a leading cause of treatment failure in Helicobacter pylori infection. In Africa, there are very little data concerning the susceptibility of Helicobacter pylori isolates to antibiotics. The purpose of this study was to evaluate the resistance prevalence of Helicobacter pylori strains circulating in Cameroon, and to assess overexpression of efflux pump as a possible multi-drug resistance mechanisms. Methods A total of 140 H. pylori isolates were recovered from gastric biopsies of dyspeptic patients in two reference hospitals in Cameroon and analyzed for their antimicrobial susceptibility to amoxicillin, co-amoxiclav, ampicillin, penicillin, imipenem, metronidazole, rifabutin, erythromycin, clarithromycin, azithromycin, levofloxacin, ciprofloxacin, norfloxacin, tetracycline, doxycycline and minocycline. Antibiotic sensitivity was tested by disk diffusion method. Phe-Arg-naphthylamide (PAßN) was used as efflux pump inhibitor. INT broth microdilution method in supplemented Brain Heart Infusion broth was used to determine the MIC of ampicillin, amoxicillin, metronidazole, erythromycin, clarithromycin and doxycycline in the absence and the presence of PAßN against 32 selected MDR isolates. Results Overall H. pylori resistance rate was 100% to ampicillin, penicillin and co-amoxiclav; 97.14% to amoxicillin, 97.85% to metronidazole, 47.85% to erythromycin, 13.57% to clarithromycin; 5, 2.86 and 0.71% to doxycycline, tetracycline and minocycline respectively. No resistance to azithromycin, rifabutin, imipenem, ciprofloxacin, norfloxacin and levofloxacin was detected among H. pylori isolates. Seventy percent (70%) of the tested isolates elicited a multiple drugs resistance pattern; 42.57% double, 15.71% triple and 5.71% quadruple drugs resistance. Metronidazole and amoxicillin were more concerned with double resistance pattern (86.76%). The spectrum of activity recorded with metronidazole, doxycycline, clarithromycin and erythromycin ranged from 0 to 100% in the absence to the presence of PAßN against the tested MDR isolates. An 8 to 128-fold increase in potency was also noticed with these antibiotics in the presence of PAßN. Conclusion With regard to the high resistance rate to both amoxicillin and metronidazole, these drugs should be avoided as components of triple therapy in our milieu. In contrast, ciprofloxacin, norfloxacin, levofloxacin and tetracyclines could be used to achieve a better eradication rate and to reduce the risk of selection of H. pylori resistant strains.

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Antibiotic Resistance of Helicobacter Pylori and Influencing Factors in Yangzhou, China: a Cross-sectional Study

10.21203/rs.3.rs-198405/v1 ◽

2021 ◽

Author(s):

Yun Zhang ◽

Xinyi Feng ◽

Lijun Bian ◽

Yan Zhang ◽

Qian Li ◽

...

Keyword(s):

Helicobacter Pylori ◽

Antibiotic Resistance ◽

Gastrointestinal Symptoms ◽

Cross Sectional Study ◽

Resistance Rate ◽

Resistance Pattern ◽

Cross Sectional ◽

Chip Technology ◽

Resistance Patterns ◽

H Pylori

Abstract Background: The Helicobacter pylori (H. pylori) antibiotic resistance pattern differs geographically, knowledge of local antimicrobial resistance pattern is key to successful eradication. The current study was performed to investigate the resistance of H. pylori to 5 commonly used antibiotics in Yangzhou.Methods: A total of 461 H. pylori strains were collected from April 2018 to September 2019 in Yangzhou and tested for their susceptibility to clarithromycin, levofloxacin, metronidazole, amoxicillin, tetracycline using gene chip technology.Results: The resistance rates of H. pylori to clarithromycin, levofloxacin, metronidazole, amoxicillin and tetracycline were 41.0%, 44.9%, 38.8%, 6.3% and 1.1%. In addition, sixteen multiple resistance patterns were detected, and fortunately there were no strains resistant to all five antibiotics. The vacA s1 allele was detected in each strain, 64.0% of the isolates were s1/m2 genotype, 36.0% s1/m1 genotype. In multivariate analysis, history of chronic superficial gastritis was significantly associated with clarithromycin resistance, strains isolated from subjects with gastrointestinal symptoms had a significantly higher likelihood of metronidazole resistance, and antibiotic resistance of H. pylori was independent of both sex and age.Conclusion: The resistance rate of H. pylori to clarithromycin, levofloxacin and metronidazole were very high in Yangzhou, the results will help in selecting effective eradication regimens.

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Helicobacter pylori antibiotic susceptibility patterns in Bangladesh: Emerging levofloxacin resistance

The Journal of Infection in Developing Countries ◽

10.3855/jidc.7713 ◽

2016 ◽

Vol 10 (03) ◽

pp. 245-253 ◽

Cited By ~ 13

Author(s):

Hafeza Aftab ◽

Muhammad Miftahussurur ◽

Phawinee Subsomwong ◽

Faruque Ahmed ◽

AK Azad Khan ◽

...

Keyword(s):

Helicobacter Pylori ◽

Triple Therapy ◽

Antibiotic Susceptibility ◽

Resistance Rate ◽

Resistance Pattern ◽

Dilution Method ◽

Agar Dilution Method ◽

Peptic Ulcers ◽

H Pylori ◽

Resistance Rates

Introduction: The most recent study to report Helicobacter pylori antibiotic resistance rates in Bangladesh was published 15 years ago and did not include levofloxacin. We therefore aimed to determine the current antibiotic susceptibility of H. pylori to amoxicillin, clarithromycin, metronidazole, tetracycline and levofloxacin in Bangladesh. Methodology: This study included 133 consecutive patients who underwent endoscopy examination at Dhaka Medical College in November 2014. The serial two-fold agar dilution method was used to determine the minimum inhibitory concentrations of the five antibiotics. Results: Among 56 cultured strains, H. pylori showed high rates of resistance to clarithromycin and metronidazole (39.3% and 94.6%, respectively). Moreover, levofloxacin showed an emerging antimicrobial resistance pattern (66.1%), which was higher in patients with gastritis than that in those with peptic ulcers (p = 0.02). The resistance rate of levofloxacin was significantly higher in patients living in Dhaka city compared to those living in the village (p = 0.049). However, amoxicillin and tetracycline resistance rates were very low. Resistance to both metronidazole and levofloxacin was most commonly observed. Conclusions: The rates of resistance to clarithromycin, metronidazole, and levofloxacin were high in Bangladesh, which suggests that triple therapy based on these drugs may not be useful as first-line therapies in Bangladesh. Alternative strategies such as furazolidone-based triple therapy, bismuth-based quadruple therapies, or sequential therapy may be more effective for patients in in Bangladesh.

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Health Care Associated Multidrug Resistant Acinetobacter Infections in a Tertiary Critical Care Center of Dhaka, Bangladesh

Journal of Bangladesh College of Physicians and Surgeons ◽

10.3329/jbcps.v38i2.45628 ◽

2020 ◽

Vol 38 (2) ◽

pp. 59-63

Author(s):

Md Faruk Mia ◽

Arif Ahmed Khan ◽

Anjana Chakraborty

Keyword(s):

Health Care ◽

Critical Care ◽

Care Center ◽

Resistance Rate ◽

Diffusion Method ◽

Multi Drug Resistance ◽

Military Hospital ◽

Resistance Pattern ◽

Cross Sectional ◽

High Dependency

Introduction: Acinetobacter spp, emerged as important pathogen exhibiting increasing antimicrobial resistance. Worldwide, multi-drug resistant Acinetobacter is being established as a significant cause of health-care-associated infections along with their resistant trait. Methods:This retrospective, cross-sectional study was done in critical care centers (CCC) of Combined Military Hospital (CMH) from May to September 2016. Total 69 patients with infection by Acinetobacter were included in this study. Center for Disease Control (CDC) criteria for selection of nosocomial infection were used. Specimen were inoculated in blood and MacConkey agar, incubated 24 hours at 37°C in aerobic condition and yield in plates were examined. Antibiotic resistance of isolated organisms were observed in Mueller Hinton agar sensitivity media by using Kirby Bauer disc diffusion method. Results:Among the total 69 (males 27, females 42,) and age range 2-75 years, Acinetobacter infected patients, 31 were from medical, 23 from surgical and 15 were from high dependency unit (HDU). Specimens were tracheal aspirate (24, 34.80%), urine (18, 26.90%), wound swab (12, 17.40%), pus (6, 8.70%), high vaginal swab (6, 8.70%) and bronchoalveolar lavage (3, 4.35%). Empiric antibiotics were given in all, one course of antibiotic was used in one, in others two or more courses were given. In the study, total 17 antibiotics were used for identifying resistance pattern of Acinetobacter isolates. Ceftazidime (91.30%), ceftriaxone (91.30%), amikacin(52.20%), gentamicin (33.33%), cotrimoxazole (50%) and ciprofloxacin (65.22%) were mostly resistant. Colistin appeared as most effective antibiotic with only 7.70% resistance rate. Conclusion: Acinetobacter, isolated in this study were resistant to most antibiotics. Colistin was the most sensitive one. Multi drug resistance (DR), extended DR and pan DR Acinetobacter organisms are reported worldwide, work on clinical presentation, trends of drug use in particular set up is important to combat the situation of ‘Going out of drug state’. J Bangladesh Coll Phys Surg 2020; 38(2): 59-63

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Bifunctional enzyme SpoT is involved in biofilm formation of Helicobacter pylori with multidrug resistance by upregulating efflux pump Hp1174 (gluP)

10.1101/321026 ◽

2018 ◽

Author(s):

Xiaoran Ge ◽

Yuying Cai ◽

Zhenghong Chen ◽

Sizhe Gao ◽

Xiwen Geng ◽

...

Keyword(s):

Drug Resistance ◽

Helicobacter Pylori ◽

Multidrug Resistance ◽

Biofilm Formation ◽

Efflux Pump ◽

Efflux Pumps ◽

Multi Drug Resistance ◽

Bifunctional Enzyme ◽

Average Expression Level ◽

H Pylori

ABSTRACTThe drug resistance of Helicobacter pylori (H. pylori) is gradually becoming a serious problem. Biofilm formation is an important factor that leads to multidrug resistance in bacteria. The ability of H. pylori to form biofilms on the gastric mucosa has been known. However, there are few studies on the regulation mechanisms of H. pylori biofilm formation and multidrug resistance. Guanosine 3’-diphosphate 5’-triphosphate and guanosine 3’,5’-bispyrophosphate [(p)ppGpp] are global regulatory factors and are synthesized in H. pylori by the bifunctional enzyme SpoT. It has been reported that (p)ppGpp is involved in the biofilm formation and multidrug resistance of various bacteria. In this study, we found that SpoT also plays an important role in H. pylori biofilm formation and multidrug resistance. Therefore, it is necessary to carry out some further studies regarding its regulatory mechanism. Considering that efflux pumps are of great importance in the biofilm formation and multidrug resistance of bacteria, we tried to find if efflux pumps controlled by SpoT participate in these activities. Then, we found that Hp1174 (glucose/galactose transporter, gluP), an efflux pump of the MFS family, is highly expressed in biofilm-forming and multi-drug resistance (MDR) H. pylori and is upregulated by SpoT. Through further research, we determined that gluP involved in H. pylori biofilm formation and multidrug resistance. Furthermore, the average expression level of gluP in clinical MDR strains was considerably higher than that in clinical drug-sensitive strains. Taken together, our results revealed a novel molecular mechanism of H. pylori tolerance to multidrug.

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In Vitro Activity of 3-Bromopyruvate, an Anticancer Compound, Against Antibiotic-Susceptible and Antibiotic-Resistant Helicobacter pylori Strains

Cancers ◽

10.3390/cancers11020229 ◽

2019 ◽

Vol 11 (2) ◽

pp. 229 ◽

Cited By ~ 7

Author(s):

Paweł Krzyżek ◽

Roman Franiczek ◽

Barbara Krzyżanowska ◽

Łukasz Łaczmański ◽

Paweł Migdał ◽

...

Keyword(s):

Helicobacter Pylori ◽

Bactericidal Activity ◽

Detection Threshold ◽

Diffusion Method ◽

Antibiotic Resistant ◽

Killing Assay ◽

Broth Microdilution Method ◽

Checkerboard Assay ◽

H Pylori ◽

Anticancer Compound

Helicobacter pylori (H. pylori) is a bacterium capable of inducing chronic active gastritis, which in some people, develops into gastric cancers. One of the substances that may be useful in the eradication of this microorganism is 3-Bromopyruvate (3-BP), an anticancer compound with antimicrobial properties. The aim of this article was to determine the activity of 3-BP against antibiotic-susceptible and antibiotic-resistant H. pylori strains. The antimicrobial activity was determined using a disk-diffusion method, broth microdilution method, time-killing assay, and checkerboard assay. The research was extended by observations using light, fluorescence, and scanning electron microscopy. The growth inhibition zones produced by 2 mg/disk with 3-BP counted for 16–32.5 mm. The minimal inhibitory concentrations (MICs) ranged from 32 to 128 μg/mL, while the minimal bactericidal concentrations (MBCs) for all tested strains had values of 128 μg/mL. The time-killing assay demonstrated the concentration-dependent and time-dependent bactericidal activity of 3-BP. The decrease in culturability below the detection threshold (<100 CFU/mL) was demonstrated after 6 h, 4 h, and 2 h of incubation for MIC, 2× MIC, and 4× MIC, respectively. Bacteria treated with 3-BP had a several times reduced mean green/red fluorescence ratio compared to the control samples, suggesting bactericidal activity, which was independent from an induction of coccoid forms. The checkerboard assay showed the existence of a synergistic/additive interaction of 3-BP with amoxicillin, tetracycline, and clarithromycin. Based on the presented results, it is suggested that 3-BP may be an interesting anti-H. pylori compound.

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Minimum inhibitory concentrations of commonly used antibiotics against Helicobacter Pylori: A multicenter study in South China

PLoS ONE ◽

10.1371/journal.pone.0256225 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0256225

Author(s):

Xueping Huang ◽

Yuan Liu ◽

Zhihui Lin ◽

Baihe Wu ◽

Gaohui Nong ◽

...

Keyword(s):

Helicobacter Pylori ◽

South China ◽

Resistance Rate ◽

Minimum Inhibitory Concentrations ◽

Microdilution Method ◽

Broth Microdilution Method ◽

Gastric Biopsies ◽

Overall Resistance ◽

Resistance Rates

Aim To determine the minimum inhibitory concentrations (MICs) of commonly used antibiotics against Helicobacter Pylori (H. pylori) in South China and compare their resistance rates by using EUCAST breakpoints and other breakpoints. Methods Patients who had not previously received H. pylori treatment in clinical centers in South China were enrolled in this study from 2017 to 2020. Gastric biopsies were obtained for H. pylori culture. The MICs of amoxicillin (AMX), clarithromycin (CLA), metronidazole (MTZ), levofloxacin (LEV), tetracycline (TET) and furazolidone (FZD) were tested by broth microdilution method and assessed by two different breakpoints. ATCC43504 standard strain served as a control. Results A total of 208 H. pylori strains were isolated from patients’ biopsy samples. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for H. pylori were 0.0156-256mg/L (MIC50 0.125mg/L, MIC90 4mg/L), 0.0156- >256 mg/L (MIC50 0.0312mg/L, MIC90 64mg/L), 0.0156- >256mg/L (MIC50 8mg/L, MIC90 256mg/L), 0.0156-256mg/L (MIC50 0.25mg/L, MIC90 16mg/L), 0.0156-256mg/L (MIC50 0.0625mg/L, MIC90 4mg/L), and 0.0156- >256mg/L (MIC50 0.0312mg/L, MIC90 2mg/L), respectively. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for ATCC43504 strain were 0.25mg/L, 0.0625mg/L, 64mg/L, 0.5mg/L, 1mg/L and 0.25mg/L, respectively. The resistance rate of FZD was 11.05%. The overall resistance rates according to EUCAST breakpoints and other breakpoints were 57.21% and 14.90% for AMX (p<0.001), 38.94% and 38.94% for CLA (p = 1), 39.42% and 50.96% for MTZ (p<0.001), 12.98% and 10.58% for TET (p = 0.025), 35.10% and 35.10% for LEV (p = 1), respectively. Conclusions Our results demonstrate that AMX, FZD, and TET, but not MTZ, CLR or LEV, showed good anti-H. pylori activity in vitro in South China. When different breakpoints were used, similar results were found with CLA, and LEV, but not with AMX, MTZ, or TET.

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Synthesis and In Vitro Enzymatic Studies of New 3-Aryldiazenyl Indoles as Promising Helicobacter pylori IMPDH Inhibitors

Current Topics in Medicinal Chemistry ◽

10.2174/1568026619666190227212334 ◽

2019 ◽

Vol 19 (5) ◽

pp. 376-382 ◽

Cited By ~ 4

Author(s):

Sachin Jangra ◽

Gayathri Purushothaman ◽

Kapil Juvale ◽

Srimadhavi Ravi ◽

Aishwarya Menon ◽

...

Keyword(s):

Helicobacter Pylori ◽

Bacterial Infections ◽

Immunosuppressive Drugs ◽

Multi Drug Resistance ◽

Metabolic Enzyme ◽

World Population ◽

Inhibitor Molecule ◽

Nucleotide Synthesis ◽

H Pylori

Background & Objective:Helicobacter pylori infection is one of the primary causes of peptic ulcer followed by gastric cancer in the world population. Due to increased occurrences of multi-drug resistance to the currently available antibiotics, there is an urgent need for a new class of drugs against H. pylori. Inosine 5′-monophosphate dehydrogenase (IMPDH), a metabolic enzyme plays a significant role in cell proliferation and cell growth. It catalyses guanine nucleotide synthesis. IMPDH enzyme has been exploited as a target for antiviral, anticancer and immunosuppressive drugs. Recently, bacterial IMPDH has been studied as a potential target for treating bacterial infections. Differences in the structural and kinetic parameters of the eukaryotic and prokaryotic IMPDH make it possible to target bacterial enzyme selectively.Methods:In the current work, we have synthesised and studied the effect of substituted 3-aryldiazenyl indoles on Helicobacter pylori IMPDH (HpIMPDH) activity. The synthesised molecules were examined for their inhibitory potential against recombinant HpIMPDH.Results:In this study, compounds 1 and 2 were found to be the most potent inhibitors amongst the database with IC50 of 0.8 ± 0.02µM and 1 ± 0.03 µM, respectively.Conclusion:When compared to the most potent known HpIMPDH inhibitor molecule C91, 1 was only four-fold less potent and can be a good lead for further development of selective and potent inhibitors of HpIMPDH.

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Analysis of babA, cagE and cagA Genes in Helicobacter pylori from Upper Gastric Patients in the North of Iran

Infectious Disorders - Drug Targets ◽

10.2174/1871526518666180515113218 ◽

2019 ◽

Vol 19 (3) ◽

pp. 274-278 ◽

Cited By ~ 1

Author(s):

Saba Fakhrieh Asl ◽

Mehrnaz Pourvahedi ◽

Ali Mojtahedi ◽

Mohammad Shenagari

Keyword(s):

Helicobacter Pylori ◽

Gastric Diseases ◽

Specific Primers ◽

The North ◽

Different Types ◽

North Of Iran ◽

Gastric Biopsies ◽

Pcr Method ◽

Non Ulcer Dyspepsia ◽

H Pylori

Objective:Helicobacter pylori is a Gram-negative bacterium which has a serious effect on up to half of the world’s population and has been related to different gastric diseases. The goal of this study was to assess the frequency of babA, cagE and cagA genotypes among H. pylori strains isolated from gastric biopsies of endoscopic patients in the north of Iran.Methods:The present study was performed on 90 strains of H. pylori isolated from patients with gastric diseases (Gastric ulcer (GU), Duodenal ulcer (DU), Gastritis (G), Non-ulcer dyspepsia (NUD) and Gastric adenocarcinoma (GC)). DNA was extracted from all isolated strains and PCR method was performed to detect the prevalence of babA2, cagE and cagA genes using specific primers.Results:Among 90 samples of H. pylori, babA2, cagE, and cagA genes were detected in 42.2%, 30% and 82.2% of strains respectively. The statistical analysis showed that the prevalence of cagA gene in GU, G, DU, and NUD was significantly higher than other genes. Moreover, cagA, and babA2 genes were significantly more prevalent in GC patients compared to cagE gene. Our isolates exhibited 8 distinct arrangements of virulence patterns. The occurrence of cagA (35.6%) was the most prevalent pattern followed by cagA/babA2 (20%) and cagA/babA2/cagE (14.4%).Conclusion:In summary, as first report from Guilan province in the north of Iran, we showed significant association between the presence of babA2, cagE, and cagA genes in different types of gastric disorders.

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Frequency of rdx A Deletion Mutation Conferring Metronidazole Resistance in Helicobacter pylori

10.51429/ejmm29308 ◽

2020 ◽

Vol 29 (3) ◽

pp. 59-64

Author(s):

Hanaa M. El Maghraby ◽

Samar Mohaseb

Keyword(s):

Helicobacter Pylori ◽

Epigastric Pain ◽

Deletion Mutation ◽

Rapid Urease Test ◽

Rrna Gene ◽

University Hospitals ◽

Metronidazole Resistance ◽

Urease Test ◽

Gastric Biopsies ◽

H Pylori

Background: Metronidazole is one of the antimicrobial drugs that can be used in combination with other drugs for eradication of Helicobacter pylori (H. pylori).Unfortunately, metronidazole resistance in H. plori is an increasing health problem which may be attributed to inactivation of many genes as rdx A gene. Objective: To determine the frequency of rdx A deletion mutation in H. pylori detected in infected patients attending at the Gastroenterology Unit, Zagazig University Hospitals. Methodology: Two gastric biopsies were taken from each enrolled patient by endoscopy. H.pylori detection was done by rapid urease test and polymerase chain reaction (PCR) amplification of 16S rRNA gene. Deletion mutation in rdx A gene was detected by conventional PCR. Results: Out of 134 doubled gastric biopsies obtained from 134 patients, 52.2% were positive for H. pylori. Epigastric pain, vomiting and gastritis were significantly associated with detection of H. pylori infection (p˂ 0.05). Deletion mutation of rdx A gene was detected in 28.6% of H. pylori positive specimens obtained from infected patients. Conclusion: Deletion mutation of rdx A gene is a frequent determinant of rdx A inactivation conferring metronidazole resistance among H. pylori.

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E-Test or Agar Dilution for Metronidazole Susceptibility Testing of Helicobacter Pylori: Importance of the Prevalence of Metronidazole Resistance

10.21203/rs.3.rs-677597/v1 ◽

2021 ◽

Author(s):

Jinnan Chen ◽

Yu Huang ◽

Zhaohui Ding ◽

Xiao Liang ◽

Hong Lu

Keyword(s):

Helicobacter Pylori ◽

Susceptibility Testing ◽

Resistance Rate ◽

Test Method ◽

Major Error ◽

Metronidazole Resistance ◽

Agar Dilution ◽

H Pylori ◽

High Level ◽

Level Resistance

Abstract Background: A number of studies have shown that E-test overestimated the presence of Helicobacter pylori (H. pylori) resistance compared to agar dilution.Objective: The purpose of this study was to explore whether E-test could be an alternative for agar dilution to detect the metronidazole susceptibility of H. pylori.Method: E-test and agar dilution were used to assess susceptibility of H. pylori to metronidazole, clarithromycin and levofloxacin in 281 clinical isolates obtained from China where resistance was high. Cohen kappa analysis, McNemar test, essential and categorical agreement analysis were performed for these two methods. Results: Overall, the result of E-test showed similar prevalence of resistance rate to all antibiotics compared with agar dilution. The essential agreement (EA) of E-test method and agar dilution in the evaluation susceptibility of H. pylori to clarithromycin and levofloxacin were moderate, with 89.0% and 79.7% respectively, but only 45.9% for metronidazole. Results showed categorical agreement (CA) between E-test and agar dilution were 100% for both clarithromycin and levofloxacin. As for metronidazole, the CA was 98.7%, no major error was identified, and rate of very major error was 1.8%.Conclusion: E-test can be an alternative method to detect the metronidazole susceptibility of H. pylori in regions where high-level resistance is common.

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