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Ng HY, Leung WK, Cheung KS. Antibiotic Resistance, Susceptibility Testing and Stewardship in Helicobacter pylori Infection. Int J Mol Sci 2023; 24:11708. [PMID: 37511471 PMCID: PMC10380565 DOI: 10.3390/ijms241411708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/12/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
Despite the declining trend of Helicobacter pylori (H. pylori) prevalence around the globe, ongoing efforts are still needed to optimize current and future regimens in view of the increasing antibiotic resistance. The resistance of H. pylori to different antibiotics is caused by different molecular mechanisms, and advancements in sequencing technology have come a far way in broadening our understanding and in facilitating the testing of antibiotic susceptibility to H. pylori. In this literature review, we give an overview of the molecular mechanisms behind resistance, as well as discuss and compare different antibiotic susceptibility tests based on the latest research. We also discuss the principles of antibiotic stewardship and compare the performance of empirical therapies based on up-to-date resistance patterns and susceptibility-guided therapies in providing effective H. pylori treatment. Studies and clinical guidelines should ensure that the treatment being tested or recommended can reliably achieve a pre-agreed acceptable level of eradication rate and take into account the variations in antibiotic resistance across populations. Local, regional and international organizations must work together to establish routine antibiotic susceptibility surveillance programs and enforce antibiotic stewardship in the treatment of H. pylori, so that it can be managed in a sustainable and efficient manner.
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Affiliation(s)
- Ho-Yu Ng
- School of Clinical Medicine, The University of Hong Kong, Hong Kong, China
| | - Wai K Leung
- Department of Medicine, School of Clinical Medicine, The University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China
| | - Ka-Shing Cheung
- Department of Medicine, School of Clinical Medicine, The University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China
- Department of Medicine, The University of Hong Kong-Shenzhen Hospital, Shenzhen 518053, China
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Binmaeil H, Hanafiah A, Mohamed Rose I, Raja Ali RA. Development and Validation of Multiplex Quantitative PCR Assay for Detection of Helicobacter pylori and Mutations Conferring Resistance to Clarithromycin and Levofloxacin in Gastric Biopsy. Infect Drug Resist 2021; 14:4129-4145. [PMID: 34675558 PMCID: PMC8502538 DOI: 10.2147/idr.s325056] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 09/08/2021] [Indexed: 12/12/2022] Open
Abstract
Aims and Objectives More than half of the world's population is infected with Helicobacter pylori, which can cause chronic gastritis. WHO has regarded clarithromycin-resistant H. pylori as a high priority pathogen. Hence, accurate diagnosis and detection of clarithromycin- and levofloxacin-resistant H. pylori strains is essential for proper management of infection. The objective of this study was to develop and optimize multiplex quantitative PCR assay for detection of mutations associated with clarithromycin and levofloxacin resistance in H. pylori directly from the gastric biopsies. Materials and Methods Specific primers and probes were designed to amplify ureA and mutations in 23S rRNA and gyrA genes. Singleplex and triplex qPCR assays were optimized and the assay's sensitivities and specificities were determined. The optimized multiplex qPCR assay was performed on 571 gastric biopsies. Results In this study, 14.7% (84/571) of the gastric biopsies were positive for H. pylori by conventional methods and 23.8% (136/571) were positive by the ureA-qPCR with 96.4% sensitivity and 88.5% specificity, while the +LR and -LR were 8.72 and 0.04, respectively. The ureA-positive samples (n=136) were subjected to multiplex qPCR which detected A2142G and A2143G mutations in the 23S rRNA gene (20.6%, 28/136) conferring clarithromycin resistance and gyrA mutations N87K, N87I, D91N, and D91Y (11.8%, 16/136) leading to levofloxacin resistance. The sensitivity and specificity of qPCR of 23S rRNA gene were 100% and 98.7%, respectively, while 100% and 99.8% for qPCR of gyrA, respectively. Conclusion The effectiveness of this qPCR is that it is sensitive in detecting low bacterial load and will help in timely detection of clarithromycin- and levofloxacin-resistant strains, especially in case of mixed infections. Since it is culture independent, it can inform clinicians about antibiotics to be included in the first-line therapy, thereby improving the management of H. pylori infection at a much greater pace.
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Affiliation(s)
- Hasyanee Binmaeil
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, 56000, Malaysia
| | - Alfizah Hanafiah
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, 56000, Malaysia.,GUT Research Group, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, 56000, Malaysia
| | - Isa Mohamed Rose
- Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, 56000, Malaysia
| | - Raja Affendi Raja Ali
- GUT Research Group, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, 56000, Malaysia.,Department of Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, 56000, Malaysia
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Anis S, Farooqi SR, Niaz SK. Characterization of Domain V Mutations in Clinical Isolates of Helicobacter pylori in Pakistan and Their Effect on Clarithromycin MIC. Infect Drug Resist 2021; 14:3393-3403. [PMID: 34466005 PMCID: PMC8402994 DOI: 10.2147/idr.s306878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/06/2021] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Clarithromycin is commonly prescribed for H. pylori infection. Domain V mutations are responsible for clarithromycin resistance. This study was aimed to characterize the clarithromycin resistance and its associated mutations in clinical isolates of H. pylori in Pakistan. MATERIALS AND METHODS Infection was diagnosed in 93 patients' biopsies using culture, rapid urease test, 16S rRNA, and vacA gene multiplex PCR. Clarithromycin resistance was assessed by the agar dilution method. Mutations were detected by PCR-RFLP using 46 (1.4 kb) domain V fragments. Sequencing was executed for 13 domain V fragments, of which 12 showed unusual amplicon size (1.2 kb) and 01 had a new MboII RFLP pattern. RESULTS A total of 48 (83%) strains were obtained from 58 (62.3%) PCR H. pylori-positive samples. Resistance (MIC ≥ 0.001 mg/mL) and intermediate resistance phenotype (MIC = 0.0005 mg/mL) was observed in 22 (46%), and 10 (21%) isolates, respectively. The primary resistance was found in 23 (39.6%) samples. PCR-RFLP detected A2142G, A2143G, and double mutations in 19, 04, and 01 resistant strain, respectively. Sequencing of 10 amplicons obtained from intermediated resistant strains and 03 amplicons from resistant strains showed 138 new mutations. Among them, T2182C was also seen in 04 intermediated resistant isolates, whereas A2142G, A2143G, and A2143C were observed in resistant isolates. The new MboII RFLP pattern in an intermediated resistant strains was due to A1761G mutation. CONCLUSION H. pylori domain V mutations showed extensive diversity. Multiple mutations in domain V may give endurance to H. pylori against clarithromycin. Further investigations on the molecular mechanism of antibiotic resistance in H. pylori seem crucial at this stage.
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Affiliation(s)
- Shumaiza Anis
- Department of Genetics, University of Karachi, Karachi, Sindh, Pakistan
| | - Shakeel R Farooqi
- Department of Genetics, University of Karachi, Karachi, Sindh, Pakistan
| | - Saad K Niaz
- Surgical Unit IV, Civil Hospital, Karachi, Sindh, Pakistan
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4
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Yin G, Bie S, Gu H, Shu X, Zheng W, Peng K, Zhao H, Li F, Chen B, Botchway BOA, Fang M, Jiang M. Application of gene chip technology in the diagnostic and drug resistance detection of Helicobacter pylori in children. J Gastroenterol Hepatol 2020; 35:1331-1339. [PMID: 31930581 DOI: 10.1111/jgh.14980] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 10/08/2019] [Accepted: 01/05/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Helicobacter pylori (HP) culture for diagnosing HP infection is time-consuming and technologically complex. This study evaluated the clinical significance of gastric mucosal gene chip technology in the rapid diagnosis of HP infection and detection of drug resistance in children. METHODS Patients (between the age of 2.5 and 16.0 years old) manifesting gastrointestinal symptoms were enrolled in this study. HP culture of gastric mucosa and drug sensitivity test were performed. A gene chip of gastric mucosa was used to detect the presence of HP infection, some single nucleotide polymorphisms in HP drug resistance genes, or associated gene mutation. DNA sequencing was investigated and compared with the gene chip test results. RESULTS Out of 267 cases, HP culture was positive in 169 cases and negative in 98 cases. HP detection by the gene chip method was positive in 208 cases and negative in 59 cases. The sensitivity, specificity, and accuracy of the gene chip technology for diagnosing HP infection were 96.1, 85.0, and 93.6%, respectively. HP resistance gene locus using the gene chip showed the main mutation locus of clarithromycin to be 2143A/G, levofloxacin at locus GyrA 91 and GyrA 87, and amoxicillin at PBP1 556ser. Concordance rates between gene chip and DNA sequencing for VacA-S/M, 16S rRNA, 23S rRNA, and GyrA were greater than 95%, and that of PBP1 was greater than 82%. CONCLUSION Gastric mucosal gene chip technology can be used for rapid diagnosis and drug resistance detection of HP infection in children.
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Affiliation(s)
- Guofeng Yin
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.,Department of Pediatrics, Shaoxing Women and Children's Hospital, Shaoxing, China
| | - Shuxian Bie
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Hongdan Gu
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Xiaoli Shu
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Wei Zheng
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Kerong Peng
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Hong Zhao
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Fubang Li
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Bo Chen
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Benson O A Botchway
- Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou, China
| | - Marong Fang
- Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou, China
| | - Mizu Jiang
- Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
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Genotypic and Phenotypic Resistance to Clarithromycin in Helicobacter pylori Strains. J Clin Med 2020; 9:jcm9061930. [PMID: 32575584 PMCID: PMC7356929 DOI: 10.3390/jcm9061930] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/10/2020] [Accepted: 06/17/2020] [Indexed: 12/12/2022] Open
Abstract
Background: The increasing prevalence of antimicrobial resistance, together with the lack of novel treatment options, negatively affects successful eradication of Helicobacter pylori. The aim of this study was to investigate genetic mutations in the 23S rRNA genes, which is associated with clarithromycin resistance, and to determine the clinical impact of genotype on phenotypic antimicrobial resistance. Methods: A total of 46 H. pylori strains were obtained from 13 patients, before and after unsuccessful eradication with clarithromycin-based triple therapy. The phenotypic resistance of each H. pylori strain was determined by minimum inhibitory concentration against clarithromycin using the serial two-fold agar dilution method. The genomic sequences of 23S rRNA genes were identified through next-generation sequencing, and nucleotide variants were determined based on comparison with genome sequences of the reference strain H. pylori 26695. Results: Clarithromycin resistance was found in 9 of 13 subjects before treatment and all subjects after unsuccessful eradication. Whole-genome sequencing of the 23S rRNA genes detected 42 mutations on 40 nonidentical loci, including 2147A>G (formerly 2143A>G) and 2146A>G (formerly 2142A>G). All strains with clarithromycin-resistant phenotype had either 2147A>G or 2146A>G mutation. When comparing genotype and phenotype for clarithromycin resistance, there was a significant association between 2147A>G mutation and clarithromycin-resistant phenotype. Conclusions: All clarithromycin-resistant strains had either 2146A>G or 2147A>G mutation, suggesting that tests targeting these two mutations may be enough for the prediction of clarithromycin resistance in this population.
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Marques AT, Vítor JMB, Santos A, Oleastro M, Vale FF. Trends in Helicobacter pylori resistance to clarithromycin: from phenotypic to genomic approaches. Microb Genom 2020; 6:e000344. [PMID: 32118532 PMCID: PMC7200067 DOI: 10.1099/mgen.0.000344] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 02/10/2020] [Indexed: 12/15/2022] Open
Abstract
For a long time Helicobacter pylori infections have been treated using the macrolide antibiotic, clarithromycin. Clarithromycin resistance is increasing worldwide and is the most common cause of H. pylori treatment failure. Here we review the mechanisms of antibiotic resistance to clarithromycin, detailing the individual and combinations of point mutations found in the 23S rRNA gene associated with resistance. Additionally, we consider the methods used to detect clarithromycin resistance, emphasizing the use of high-throughput next-generation sequencing methods, which were applied to 17 newly sequenced pairs of H. pylori strains isolated from the antrum and corpus of a recent colonized paediatric population. This set of isolates was composed of six pairs of resistant strains whose phenotype was associated with two point mutations found in the 23S rRNA gene: A2142C and A2143G. Other point mutations were found simultaneously in the same gene, but, according to our results, it is unlikely that they contribute to resistance. Further, among susceptible isolates, genomic variations compatible with mutations previously associated with clarithromycin resistance were detected. Exposure to clarithromycin may select low-frequency variants, resulting in a progressive increase in the resistance rate due to selection pressure.
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Affiliation(s)
- Andreia T. Marques
- Host–Pathogen Interactions Unit, Research Institute for Medicines (iMed-ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal
| | - Jorge M. B. Vítor
- Host–Pathogen Interactions Unit, Research Institute for Medicines (iMed-ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, 1649 003 Lisbon, Portugal
| | - Andrea Santos
- National Reference Laboratory for Gastrointestinal Infections, Department of Infectious Diseases, National Institute of Health Dr Ricardo Jorge, Lisbon, Portugal
| | - Mónica Oleastro
- National Reference Laboratory for Gastrointestinal Infections, Department of Infectious Diseases, National Institute of Health Dr Ricardo Jorge, Lisbon, Portugal
| | - Filipa F. Vale
- Host–Pathogen Interactions Unit, Research Institute for Medicines (iMed-ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal
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7
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High prevalence of clarithromycin resistance and effect on Helicobacter pylori eradication in a population from Santiago, Chile: cohort study and meta-analysis. Sci Rep 2019; 9:20070. [PMID: 31882676 PMCID: PMC6934858 DOI: 10.1038/s41598-019-56399-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 12/11/2019] [Indexed: 12/20/2022] Open
Abstract
Helicobacter pylori (H. pylori) eradication using standard triple therapy (STT) with proton pump inhibitors (PPI), amoxicillin and clarithromycin (CLA) has been the standard in Latin America. However, CLA resistance is a rising problem affecting eradication rates. Genetic polymorphisms of CYP2C19, a PPI metabolizer may also affect eradication. The primary aims of this study were to evaluate the effect of clarithromycin resistance on H. pylori eradication in a population from Santiago, and to establish the pooled clarithromycin resistance in Santiago, Chile. Symptomatic adult patients attending a tertiary hospital in Santiago were recruited for this study. CLA resistance and the polymorphisms of CYP2C19 were determined on DNA extracted from gastric biopsies, using PCR. The STT was indicated for 14 days and eradication was determined by a urea breath test 4–6 weeks after therapy. A meta-analysis of CLA resistance studies among adult residents in Santiago was performed. Seventy-three out of 121 consecutive patients had positive rapid urease test (RUT) and received STT. Sixty-nine patients (95%) completed the study. The H. pylori eradication rate was 63% and the prevalence of CLA resistance was 26%. According to the CYP2C19 polymorphisms, 79.5% of the RUT-positive patients were extensive metabolizers. Multivariable analyses showed that only CLA resistance was significantly and inversely associated with failure of eradication (OR: 0.13; 95% confidence interval [95% CI], 0.04–0.49). A meta-analysis of two previous studies and our sample set (combined n = 194) yielded to a pooled prevalence of CLA resistance of 31.3% (95% CI 23.9–38.7). Our study shows that CLA resistance is associated with failure of H. pylori eradication. Given the high pooled prevalence of CLA resistance, consideration of CLA free therapies in Santiago is warranted. We could recommend bismuth quadruple therapy or high-dose dual therapy, according to bismuth availability. Further studies need to evaluate the best therapy.
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Mahant S, Sharma AK, Gehlot V, Mukhopadhyay AK, Chhawchharia A, Dutta S, Agarwal A, Som A, Das K, Das R. Geographically distinct North-East Indian Helicobacter pylori strains are highly sensitive to clarithromycin but are levofloxacin resistant. Indian J Med Microbiol 2019; 37:337-344. [PMID: 32003330 DOI: 10.4103/ijmm.ijmm_19_158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Purpose Helicobacter pylori causes various gastro-intestinal diseases. Antibiotic resistance to commonly used antibiotics for the treatment of H. pylori infection is the major cause for treatment failure. The aim of this study is to determine the antimicrobial susceptibility pattern for clarithromycin and levofloxacin and find the evolutionary relationship of the partial sequence of 23S rRNA and gyraseA gene of H. pylori by phylogenetic analysis. Materials and Methods A total of 46 H. pylori strains were tested for clarithromycin and levofloxacin susceptibility pattern and phylogenetic tree were reconstructed by PhyML software. Results In this study, we observed that only 6.5% of North-East Indian H. pylori strains were resistant for clarithromycin showing mutation at A2143G and T2182C positions of 23S rRNA gene. Resistance for levofloxacin was observed in 89.1% of the H. pylori strains showing mutations at asparagine to lysine at 87 and aspartic acid to glycine/tyrosine/asparagine at 91 positions of gyraseA gene. The phylogenetic tree of the partial sequence of 23S rRNA and gyraseA gene depicts that the North-East Indian strains falls in different cluster when compared to other countries. Conclusions Resistance for clarithromycin was less in North-East Indian strains but high for levofloxacin indicating that first-line therapy may be best and effective for eradication of H. pylori in this region. This study is the first report that showed antibiotic susceptibility pattern for clarithromycin and levofloxacin by mutation analysis. By partial sequencing of 23s rRNA and gyraseA gene, we found that North-East Indian strains are geographically distinct.
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Affiliation(s)
- Shweta Mahant
- Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India
| | - Amresh Kumar Sharma
- Centre of Bioinformatics, University of Allahabad, Allahabad, Uttar Pradesh, India
| | - Valentina Gehlot
- Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India
| | - Asish Kumar Mukhopadhyay
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India
| | - Ayushi Chhawchharia
- Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India
| | - Sangitanjan Dutta
- Department of Gastroenterology, Gauhati Medical College, Guwahati, Assam, India
| | - Anil Agarwal
- Department of Gastroenterology, Gauhati Medical College, Guwahati, Assam, India
| | - Anup Som
- Centre of Bioinformatics, University of Allahabad, Allahabad, Uttar Pradesh, India
| | - Kunal Das
- Department of Gastroenterology and Hepatology, Max Super Specialty Hospital, Vaishali, Ghaziabad, Uttar Pradesh, India
| | - Rajashree Das
- Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India
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Bluemel B, Goelz H, Goldmann B, Grüger J, Hamel H, Loley K, Ludolph T, Meyer J, Miehlke S, Mohr A, Tüffers K, Usadel H, Wagner S, Wenzel H, Wiemer L, Vorreiter J, Eisele B, Hofreuter D, Glocker EO. Antimicrobial resistance of Helicobacter pylori in Germany, 2015 to 2018. Clin Microbiol Infect 2019; 26:235-239. [PMID: 31212078 DOI: 10.1016/j.cmi.2019.06.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 05/31/2019] [Accepted: 06/05/2019] [Indexed: 12/21/2022]
Abstract
OBJECTIVES National 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. METHODS Gastric 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. RESULTS Overall 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). CONCLUSIONS Clarithromycin 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.
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Affiliation(s)
- B Bluemel
- Institute of Medical Microbiology and Hygiene, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - H Goelz
- Institute of Medical Microbiology and Hygiene, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | | | - J Grüger
- Department of Internal Medicine, Heilig-Geist-Hospital, Bensheim, Germany
| | - H Hamel
- Department of Internal Medicine, German Armed Forces Hospital Berlin, Berlin, Germany
| | - K Loley
- Medical Centre for Internal Medicine, Bocholt, Germany
| | - T Ludolph
- Department of Internal Medicine, District Hospital of Frankenberg, Frankenberg, Germany
| | - J Meyer
- Praxis für Gastroenterologie, Berlin, Germany
| | - S Miehlke
- University Centre for Oesophageal Diseases, University Hospital Eppendorf, Hamburg, Germany; Centre of Digestive Diseases, Internal Medicine Center Eppendorf, Hamburg, Germany
| | - A Mohr
- Internistische Gemeinschaftspraxis, Lübeck-Travemünde, Germany
| | - K Tüffers
- Department of Internal Medicine, St Johannes Hospital Dortmund, Dortmund, Germany
| | - H Usadel
- Department of Internal Medicine, Spital Schiers, Schiers, Switzerland
| | - S Wagner
- Department of Internal Medicine, Donau-Isar Clinical Centre, Deggendorf, Germany
| | - H Wenzel
- Gemeinschaftspraxis für Gastroenterologie, Wuppertal, Germany
| | - L Wiemer
- Department of Internal Medicine and Oncology, St Agnes Hospital, Bocholt, Germany
| | - J Vorreiter
- Institute of Medical Microbiology and Hygiene, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - B Eisele
- Institute of Medical Microbiology and Hygiene, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - D Hofreuter
- Institute of Laboratory Medicine, Brandenburg Hospital, Brandenburg Medical School, Brandenburg, Germany; German Federal Institute for Risk Assessment, Department of Biological Safety, Berlin, Germany
| | - E-O Glocker
- Institute of Medical Microbiology and Hygiene, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany; Institute of Laboratory Medicine, Brandenburg Hospital, Brandenburg Medical School, Brandenburg, Germany.
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Genetic Determinants and Prediction of Antibiotic Resistance Phenotypes in Helicobacter pylori. J Clin Med 2019; 8:jcm8010053. [PMID: 30621024 PMCID: PMC6351930 DOI: 10.3390/jcm8010053] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 12/29/2018] [Accepted: 12/31/2018] [Indexed: 12/11/2022] Open
Abstract
Helicobacter pylori is a major human pathogen. Diagnosis of H. pylori infection and determination of its antibiotic susceptibility still mainly rely on culture and phenotypic drug susceptibility testing (DST) that is time-consuming and laborious. Whole genome sequencing (WGS) has recently emerged in medical microbiology as a diagnostic tool for reliable drug resistance prediction in bacterial pathogens. The aim of this study was to compare phenotypic DST results with the predictions based on the presence of genetic determinants identified in the H. pylori genome using WGS. Phenotypic resistance to clarithromycin, metronidazole, tetracycline, levofloxacin, and rifampicin was determined in 140 clinical H. pylori isolates by E-Test®, and the occurrence of certain single nucleotide polymorphisms (SNPs) in target genes was determined by WGS. Overall, there was a high congruence of >99% between phenotypic DST results for clarithromycin, levofloxacin, and rifampicin and SNPs identified in the 23S rRNA, gyrA, and rpoB gene. However, it was not possible to infer a resistance phenotype for metronidazole based on the occurrence of distinct SNPs in frxA and rdxA. All 140 H. pylori isolates analysed in this study were susceptible to tetracycline, which was in accordance with the absence of double or triple nucleotide substitutions in the 16S rRNA gene.
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Genotyping and antimicrobial resistance patterns of Helicobacter pylori in human and dogs associated with A2142G and A2143G point mutations in clarithromycin resistance. Microb Pathog 2018; 123:330-338. [DOI: 10.1016/j.micpath.2018.07.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 07/12/2018] [Accepted: 07/13/2018] [Indexed: 02/07/2023]
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Gonzalez-Hormazabal P, Musleh M, Escandar S, Valladares H, Lanzarini E, Castro VG, Jara L, Berger Z. Prevalence of clarithromycin resistance in Helicobacter pylori in Santiago, Chile, estimated by real-time PCR directly from gastric mucosa. BMC Gastroenterol 2018; 18:91. [PMID: 29925321 PMCID: PMC6011593 DOI: 10.1186/s12876-018-0820-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 06/07/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Current available treatments for Helicobacter pylori eradication are chosen according to local clarithromycin and metronidazole resistance prevalence. The aim of this study was to estimate, by means of molecular methods, both clarithromycin and metronidazole resistance in gastric mucosa from patients infected with H.pylori. METHODS A total of 191 DNA samples were analyzed. DNA was purified from gastric mucosa obtained from patients who underwent an upper gastrointestinal endoscopy at an university hospital from Santiago, Chile, between 2011 and 2014. H.pylori was detected by real-time PCR. A 5'exonuclease assay was developed to detect A2142G and A2143G mutations among H.pylori-positive samples. rdxA gene was sequenced in samples harboring A2142G and A2143G mutations in order to detect mutations that potentially confer dual clarithromycin and metronidazole resistance. RESULTS Ninety-three (93) out of 191 DNA samples obtained from gastric mucosa were H.pylori-positive (48.7%). Clarithromycin-resistance was detected in 29 samples (31.2% [95%CI 22.0-41.6%]). The sequencing of rdxA gene revealed that two samples harbored truncating mutations in rdxA, one sample had an in-frame deletion, and 11 had amino acid changes that likely cause metronidazole resistance. CONCLUSIONS We estimated a prevalence of clarithomycin-resistance of 31.8% in Santiago, Chile. Three of them harbor inactivating mutations in rdxA and 11 had missense mutations likely conferring metronidazole resistance. Our results require further confirmation. Nevertheless, they are significant as an initial approximation in re-evaluating the guidelines for H.pylori eradication currently used in Chile.
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Affiliation(s)
- Patricio Gonzalez-Hormazabal
- Human Genetics Program, Institute of Biomedical Sciences, School of Medicine, University of Chile, Av. Independencia 1027, 8380453, Santiago, CL, Chile.
| | - Maher Musleh
- Department of Gastroenterology, University of Chile Clinical Hospital, Santiago, Chile.,Department of Surgery, University of Chile Clinical Hospital, Santiago, Chile
| | - Susana Escandar
- Department of Gastroenterology, University of Chile Clinical Hospital, Santiago, Chile
| | - Hector Valladares
- Department of Gastroenterology, University of Chile Clinical Hospital, Santiago, Chile.,Department of Surgery, University of Chile Clinical Hospital, Santiago, Chile
| | - Enrique Lanzarini
- Department of Gastroenterology, University of Chile Clinical Hospital, Santiago, Chile.,Department of Surgery, University of Chile Clinical Hospital, Santiago, Chile
| | - V Gonzalo Castro
- Human Genetics Program, Institute of Biomedical Sciences, School of Medicine, University of Chile, Av. Independencia 1027, 8380453, Santiago, CL, Chile
| | - Lilian Jara
- Human Genetics Program, Institute of Biomedical Sciences, School of Medicine, University of Chile, Av. Independencia 1027, 8380453, Santiago, CL, Chile
| | - Zoltan Berger
- Department of Gastroenterology, University of Chile Clinical Hospital, Santiago, Chile
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13
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Arslan N, Yılmaz Ö, Demiray-Gürbüz E. Importance of antimicrobial susceptibility testing for the management of eradication in Helicobacter pylori infection. World J Gastroenterol 2017; 23:2854-2869. [PMID: 28522904 PMCID: PMC5413781 DOI: 10.3748/wjg.v23.i16.2854] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 02/06/2017] [Accepted: 03/30/2017] [Indexed: 02/06/2023] Open
Abstract
The management of Helicobacter pylori (H. pylori) infection treatment differs from the common treatment protocol for other infectious diseases. Because culture- or molecular-guided approaches face several practical issues, such as the invasive procedures required to obtain gastric biopsy specimens and the lack of availability of routine laboratory testing in some places, H. pylori treatment includes the administration of two or three empirically selected antibiotics combined with a proton pump inhibitor rather than evidence-based eradication treatment. The efficacy of empirical therapy is decreasing, mostly due to increasing multiple resistance. Multiresistance to levofloxacin, clarithromycin, and metronidazole, which are commonly used in empirical treatments, appears to have increased in many countries. Mutations play a primary role in the antimicrobial resistance of H. pylori, but many different mechanisms can be involved in the development of antibiotic resistance. Determining and understanding these possible mechanisms might allow the development of new methods for the detection of H. pylori and the determination of antimicrobial resistance. A treatment based on the detection of antimicrobial resistance is usually more effective than empirical treatment. Nevertheless, such an approach before treatment is still not recommended in the Maastricht guidelines due to the difficulty associated with the routine application of available culture- or molecular-based susceptibility tests, which are usually administered in cases of treatment failure. The management of first and rescue treatments requires further research due to the steadily increase in antimicrobial resistance.
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14
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Demiray-Gürbüz E, Yılmaz Ö, Olivares AZ, Gönen C, Sarıoğlu S, Soytürk M, Tümer S, Altungöz O, Şimşek İ, Perez Perez GI. Rapid identification of Helicobacter pylori and assessment of clarithromycin susceptibility from clinical specimens using FISH. JOURNAL OF PATHOLOGY CLINICAL RESEARCH 2016; 3:29-37. [PMID: 28138399 PMCID: PMC5259560 DOI: 10.1002/cjp2.57] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/03/2016] [Accepted: 08/12/2016] [Indexed: 12/21/2022]
Abstract
Helicobacter pylori remains one of the most common bacterial infections worldwide. Clarithromycin resistance is the most important cause of H. pylori eradication failures. Effective antibiotic therapies in H. pylori infection must be rapidly adapted to local resistance patterns. We investigated the prevalence of clarithromycin resistance due to mutations in positions 2142 and 2143 of 23SrRNA gene of H. pylori by fluorescence in situ hybridisation (FISH), and compared with culture and antimicrobial susceptibility testing in 234 adult patients with dyspepsia who were enrolled. Antrum and corpus biopsy specimens were obtained for rapid urease test, histopathology and culture. Epsilometer test was used to assess clarithromycin susceptibility. H. pylori presence and clarithromycin susceptibility were determined by FISH in paraffin‐embedded biopsy specimens. We found that 164 (70.1%) patients were positive for H. pylori based on clinical criteria, 114 (69.5% CI 62.5–76.6%) were culture positive, and 137 (83.5% CI 77.8–89.2%) were FISH positive. Thus the sensitivity of FISH was significantly superior to that of culture. However specificity was not significantly different (91.4 versus 100.0%, respectively). The resistance rate to clarithromycin for both antrum and corpus was detected in H. pylori‐positive patients; 20.2% by FISH and 28.0% by E‐test.The concordance between E‐test and FISH was only 89.5% due to the presence of point mutations different from A2143G, A2142G or A2142C. We conclude that FISH is significantly more sensitive than culture and the E‐test for the detection of H. pylori and for rapid determinination of claritromycin susceptibility. The superior hybridisation efficiency of FISH is becoming an emerging molecular tool as a reliable, rapid and sensitive method for the detection and visualisation of H. pylori, especially when the management of H. pylori eradication therapy is necessary. This is particularly important for the treatment of patients with H. pylori eradication failure.
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Affiliation(s)
- Ebru Demiray-Gürbüz
- Department of Medical Microbiology, Faculty of Medicine Dokuz Eylül University İzmir Turkey
| | - Özlem Yılmaz
- Department of Medical Microbiology, Faculty of Medicine Dokuz Eylül University İzmir Turkey
| | - Asalia Z Olivares
- Departments of Medicine and Microbiology New York University, School of Medicine, NYUSM New York NY USA
| | - Can Gönen
- Departments of Gastroenterology, Faculty of Medicine Dokuz Eylül University Izmir Turkey
| | - Sülen Sarıoğlu
- Pathology, Faculty of Medicine Dokuz Eylül University Izmir Turkey
| | - Müjde Soytürk
- Departments of Gastroenterology, Faculty of Medicine Dokuz Eylül University Izmir Turkey
| | - Sait Tümer
- Medical Biology and Genetics, Faculty of Medicine Dokuz Eylül University İzmir Türkiye
| | - Oğuz Altungöz
- Medical Biology and Genetics, Faculty of Medicine Dokuz Eylül University İzmir Türkiye
| | - İlkay Şimşek
- Departments of Gastroenterology, Faculty of Medicine Dokuz Eylül University Izmir Turkey
| | - Guillermo I Perez Perez
- Departments of Medicine and Microbiology New York University, School of Medicine, NYUSM New York NY USA
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15
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Hu Y, Zhang M, Lu B, Dai J. Helicobacter pylori and Antibiotic Resistance, A Continuing and Intractable Problem. Helicobacter 2016; 21:349-63. [PMID: 26822340 DOI: 10.1111/hel.12299] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Helicobacter pylori, a human pathogen with a high global prevalence, is the causative pathogen for multiple gastrointestinal diseases, especially chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric malignancies. Antibiotic therapies remain the mainstay for H. pylori eradication; however, this strategy is hampered by the emergence and spread of H. pylori antibiotic resistance. Exploring the mechanistic basis of this resistance is becoming one of the major research questions in contemporary biomedical research, as such knowledge could be exploited to devise novel rational avenues for counteracting the existing resistance and devising strategies to avoid the development of a novel anti-H. pylori medication. Encouragingly, important progress in this field has been made recently. Here, we attempt to review the current state and progress with respect to the molecular mechanism of antibiotic resistance for H. pylori. A picture is emerging in which mutations of various genes in H. pylori, resulting in decreased membrane permeability, altered oxidation-reduction potential, and a more efficient efflux pump system. The increased knowledge on these mechanisms produces hope that antibiotic resistance in H. pylori can ultimately be countered.
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Affiliation(s)
- Yue Hu
- Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Meng Zhang
- Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Bin Lu
- Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China.
| | - Jinfeng Dai
- Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
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16
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Zerbetto De Palma G, Mendiondo N, Wonaga A, Viola L, Ibarra D, Campitelli E, Salim N, Corti R, Goldman C, Catalano M. Occurrence of Mutations in the Antimicrobial Target Genes Related to Levofloxacin, Clarithromycin, and Amoxicillin Resistance in Helicobacter pylori Isolates from Buenos Aires City. Microb Drug Resist 2016; 23:351-358. [PMID: 27391421 DOI: 10.1089/mdr.2015.0361] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Domain V of 23S rRNA, gyrA and gyrB Quinolones Resistance-Determining Region (QRDR), and pbp-1A gene point mutations were investigated in Helicobacter pylori-resistant isolates from three centres of Buenos Aires. Minimal inhibitory concentrations (MICs) were performed in 197 isolates from 52 H. pylori-positive naive patients by agar dilution method. Point mutations were achieved by amplification and sequencing of the target genes, and their association with resistance was determined by natural transformation assays. Resistance rates were as follows: metronidazole 28.8%, clarithromycin (CLA) 26.9%, levofloxacin (LEV) 32.7%, and amoxicillin (AMX) 7.6%. Nearly one-third of patients carried multidrug-resistant isolates. A2143G or A2142G in domain V of 23S-rRNA was found in all isolates showing high level of resistance to CLA (MIC >2 mg/L), accounting for 76.0% (38/50) of those with the resistant phenotype. The mutations A2267G or T1861C carried by 8/12 isolates with MIC 1-2 mg/L (low level) did not confer resistance by transformation. Substitutions at GyrA position 87 or 91, mainly N87K and D91G, were found in 92.8% (52/56) of the LEV-resistant isolates: 48 isolates with MIC 4-64 mg/L and 4/8 isolates with MIC 2 mg/L. The remaining four harboured K133N, also present in susceptible isolates. None of the substitutions in GyrB demonstrated to confer resistance. Transformation proved that PBP-1A N562Y and/or T556S substitutions confer the AMX resistance in our isolates, showing an additive effect. In conclusion, the usually reported mutations related to CLA, LEV, and AMX resistance were found in our isolates. However, low-level CLA resistance seems not to be due to mutations in Domain V of 23S rRNA gene.
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Affiliation(s)
- Gerardo Zerbetto De Palma
- 1 Universidad de Buenos Aires, CONICET, Instituto de Microbiología y Parasitología Médica (IMPAM), Facultad de Medicina, Buenos Aires, Argentina
| | - Nicolas Mendiondo
- 1 Universidad de Buenos Aires, CONICET, Instituto de Microbiología y Parasitología Médica (IMPAM), Facultad de Medicina, Buenos Aires, Argentina
| | - Andrés Wonaga
- 2 Centro Integral de Gastroenterología , Buenos Aires, Argentina
| | - Luis Viola
- 2 Centro Integral de Gastroenterología , Buenos Aires, Argentina
| | - Daniela Ibarra
- 3 Servicio de Gastroenterología, Hospital Aeronáutico Central , Buenos Aires, Argentina
| | - Esteban Campitelli
- 3 Servicio de Gastroenterología, Hospital Aeronáutico Central , Buenos Aires, Argentina
| | - Nicolas Salim
- 4 Servicio de Estómago y Esófago, Hospital de Gastroenterología Bonorino Udaondo , Buenos Aires, Argentina
| | - Rodolfo Corti
- 4 Servicio de Estómago y Esófago, Hospital de Gastroenterología Bonorino Udaondo , Buenos Aires, Argentina
| | - Cinthia Goldman
- 5 Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Fisicomatematica, Cátedra de Física, Buenos Aires, Argentina
| | - Mariana Catalano
- 1 Universidad de Buenos Aires, CONICET, Instituto de Microbiología y Parasitología Médica (IMPAM), Facultad de Medicina, Buenos Aires, Argentina
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17
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Low prevalence of clarithromycin-resistant Helicobacter pylori isolates with A2143G point mutation in the 23S rRNA gene in North India. J Glob Antimicrob Resist 2016; 6:39-43. [PMID: 27530837 DOI: 10.1016/j.jgar.2016.02.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 02/11/2016] [Accepted: 02/17/2016] [Indexed: 12/12/2022] Open
Abstract
Resistance of Helicobacter pylori to clarithromycin is associated with a single base substitution in the 23S rRNA gene. In this study, clarithromycin-resistant H. pylori isolates were analysed for the presence of 23S rRNA gene mutations. H. pylori were isolated from 68 patients suffering from various gastroduodenal diseases in North India. Minimum inhibitory concentrations (MICs) were determined by the agar dilution method, and point mutations in clarithromycin-resistant strains were identified by PCR-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. Clarithromycin resistance was observed in 11.8% (8/68) of the H. pylori isolates in North India. The A2143G point mutation in the 23S rRNA gene was found in 87.5% (7/8) of the clarithromycin-resistant strains, and the A2142G mutation in association with the T2182C mutation was found in 12.5% (1/8). In conclusion, the continued high prevalence of clarithromycin-sensitive H. pylori strains (88.2%) observed in this study allows the use of the triple-therapy regimen for the treatment of H. pylori infection in this region. Surveillance studies need to be conducted at regular intervals for clarithromycin resistance in the population. To our knowledge, this is the first study in India to report that point mutations at position A2143G and at A2142G in association with T2182C are associated with clarithromycin resistance, confirming reports from other parts of the world.
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18
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Eghbali Z, Mojtahedi A, Moien Ansar M, Fakhrieh Asl S, Aminian K. Detection of 23SrRNA Mutations Strongly Related to Clarithromycin Resistance in Helicobacter pylori Strains Isolated From Patients in the North of Iran. Jundishapur J Microbiol 2016; 9:e29694. [PMID: 27127590 PMCID: PMC4842254 DOI: 10.5812/jjm.29694] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Revised: 11/23/2015] [Accepted: 12/02/2015] [Indexed: 12/11/2022] Open
Abstract
Background: Helicobacter pylori is curved Gram negative and microaerophilic bacilli that have infected half of the world’s population. It is recognized as the causative agent of duodenal ulcer, gastritis peptic ulcer, mucosa-associated lymphoid tissue (MALT) lymphoma and is associated with gastric adenocarcinoma. Resistance to clarithromycin is related to point mutations in 23SrRNA gene on nt 2143 and 2144, when A turns to G, and A2143G is the most important type. These mutations lead to reduced affinity of antibiotics to their ribosomal target and are considered as the main cause of treatment failure. Objectives: The aim of this study was to determine the frequency of A2143G point mutation in 23SrRNA of H.pylori strains isolated from gastric biopsies of patients in Rasht, north of Iran, by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Patients and Methods: A descriptive study was performed on 89 H.pylori strains, which were isolated from gastric biopsies of patients with gastric disorders such as gastritis, peptic ulcer, duodenal ulcer, non-ulcer dyspepsia and gastric adenocarcinoma. Isolated strains were tested for clarithromycin resistance using as breakpoint a minimum inhibitory concentration (MIC) of ≥ 1 mg/L by the E-test. The presence of H.pylori DNA was confirmed by amplifying the ureC (glmM) gene by PCR. Also, point mutation on 23SrRNA gene (A2142G and A2143G) was detected by PCR-RFLP using MboII and BsaI restriction endonucleases in all extracted DNA. Results: Of the 89 H.pylori isolates, eighty-four were susceptible to clarithromycin, while five (5.6%) were resistant. All DNA samples of resistant strains, which were treated with BsaI had A2143G mutation. There was no point mutation in the sensitive strains of H. pylori. Also, we detected no mutation on nt A2142G of resistant strains. Conclusions: In the present study, the frequency of clarithromycin resistance was lower than the other studies conducted in Iran. Resistance frequency in samples isolated from gastric ulcer was higher than other gastric disorders. Women and patients aged more than 60 years old showed the most resistance frequency in this study. All resistant strains had the A2143G genotype.
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Affiliation(s)
- Zahra Eghbali
- Department of Biology, Rasht Branch, Islamic Azad University, Rasht, IR Iran
| | - Ali Mojtahedi
- Department of Microbiology, Faculty of Medicine, Guilan University of Medical Sciences, Rasht, IR Iran
- Corresponding author: Ali Mojtahedi, Microbiology Department, Faculty of Medicine, Guilan University of Medical Sciences, Rasht, IR Iran. Tel: +98-1333690884, Fax: +98-1333690036, E-mail:
| | - Malek Moien Ansar
- Department of Biochemistry and Biophysics, Faculty of Medicine, Guilan University of Medical Sciences, Rasht, IR Iran
| | - Saba Fakhrieh Asl
- Division of Gastroenterology and Liver Disease, Gastric and Liver Disease Research Center, Guilan University of Medical Sciences, Rasht, IR Iran
| | - Keyvan Aminian
- Division of Gastroenterology and Liver Disease, Gastric and Liver Disease Research Center, Guilan University of Medical Sciences, Rasht, IR Iran
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Improved allele-specific PCR assays for detection of clarithromycin and fluoroquinolone resistant of Helicobacter pylori in gastric biopsies: identification of N87I mutation in GyrA. Diagn Microbiol Infect Dis 2014; 81:251-5. [PMID: 25600075 DOI: 10.1016/j.diagmicrobio.2014.12.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/01/2014] [Accepted: 12/10/2014] [Indexed: 12/18/2022]
Abstract
Molecular testing can rapidly detect Helicobacter pylori susceptibility using gastric biopsies. Allele-specific polymerase chain reaction (ASP-PCR) was used to identify H. pylori 23S rRNA and gyrA mutation using gastric biopsies from Colombian patients and confirmed by PCR and sequencing of the 23S rRNA and gyrA genes. The sensitivity and specificity of ASP-PCR were compared with susceptibilities measured by agar dilution. Samples included gastric biopsies from 107 biopsies with H. pylori infections and 20 H. pylori negative. The sensitivity and specificity of ASP-PCR for the 23S rRNA gene were both 100%. The sensitivity and specificity of ASP-PCR for the gyrA gene, published in 2007 by Nishizawa et al., were 52% and 92.7%, respectively; the lower sensitivity was due to the presence of mutation N87I in our samples, which were not detected by the test. In this study, we designed new primers to detect the mutation N87I in GyrA. The ASP-PCR was performed with the original primers plus the new primers. The molecular test with the new primers improved the sensitivity to 100%. In conclusion, ASP-PCR provides a specific and rapid means of predicting resistance to clarithromycin and levofloxacin in gastric biopsies.
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20
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Khademi F, Faghri J, Moghim S, Esfahani BN, Fazeli H, Poursina F, Adibi P, Madhi M, Safaei HG. The study of mutation in 23S rRNA resistance gene of Helicobacter pylori to clarithromycin in patients with gastrointestinal disorders in Isfahan - Iran. Adv Biomed Res 2014; 3:98. [PMID: 24800187 PMCID: PMC4007339 DOI: 10.4103/2277-9175.129368] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 07/10/2013] [Indexed: 01/13/2023] Open
Abstract
Background: Helicobacter pylori antimicrobial resistance is an important factor responsible for treatment failure. The purpose of this study was evaluating the prevalence of point mutations in clarithromycin-resistant clinical isolates of H. pylori in Isfahan city of Iran. Materials and Methods: Thirty isolates of H. pylori from 130 biopsy specimens were isolated by culture and confirmed by biochemical and PCR tests. The MIC of clarithromycin antibiotic for 30 clinical isolates of H. pylori was determined by E-test method. The point mutations in the 288 bp of 23S rRNA gene of H. pylori were investigated in four clarithromycin-resistant clinical isolates by PCR followed by sequencing. Results: Among 30 isolates of H. pylori, 4 cases were resistant to clarithromycin. One point mutation was found at position T2243C in the 23S rRNA gene in all resistance isolates. Conclusions: In our study, H. pylori resistance to clarithromycin associated with point mutation at position 2243 (T2243C).
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Affiliation(s)
- Farzad Khademi
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Jamshid Faghri
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sharareh Moghim
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Bahram Nasr Esfahani
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hossein Fazeli
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Farkhondeh Poursina
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Peyman Adibi
- Department of Gastroenterology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Masoumeh Madhi
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hajieh Ghasemian Safaei
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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De Francesco V, Zullo A, Giorgio F, Saracino I, Zaccaro C, Hassan C, Ierardi E, Di Leo A, Fiorini G, Castelli V, Lo Re G, Vaira D. Change of point mutations in Helicobacter pylori rRNA associated with clarithromycin resistance in Italy. J Med Microbiol 2013; 63:453-457. [PMID: 24344205 DOI: 10.1099/jmm.0.067942-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Primary clarithromycin resistance is the main factor affecting the efficacy of Helicobacter pylori therapy. This study aimed: (i) to assess the concordance between phenotypic (culture) and genotypic (real-time PCR) tests in resistant strains; (ii) to search, in the case of disagreement between the methods, for point mutations other than those reported as the most frequent in Europe; and (iii) to compare the MICs associated with the single point mutations. In order to perform real-time PCR, we retrieved biopsies from patients in whom H. pylori infection was successful diagnosed by bacterial culture and clarithromycin resistance was assessed using the Etest. Only patients who had never been previously treated, and with H. pylori strains that were either resistant exclusively to clarithromycin or without any resistance, were included. Biopsies from 82 infected patients were analysed, including 42 strains that were clarithromycin resistant and 40 that were clarithromycin susceptible on culture. On genotypic analysis, at least one of the three most frequently reported point mutations (A2142C, A2142G and A2143G) was detected in only 23 cases (54.8%), with a concordance between the two methods of 0.67. Novel point mutations (A2115G, G2141A and A2144T) were detected in a further 14 out of 19 discordant cases, increasing the resistance detection rate of PCR to 88% (P<0.001; odds ratio 6.1, 95% confidence interval 2-18.6) and the concordance to 0.81. No significant differences in MIC values among different point mutations were observed. This study suggests that: (i) the prevalence of the usually reported point mutations may be decreasing, with a concomitant emergence of new mutations; (ii) PCR-based methods should search for at least six point mutations to achieve good accuracy in detecting clarithromycin resistance; and (iii) none of the tested point mutations is associated with significantly higher MIC values than the others.
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Affiliation(s)
| | - Angelo Zullo
- Gastroenterology and Digestive Endoscopy, 'Nuovo Regina Margherita' Hospital, Rome, Italy
| | - Floriana Giorgio
- Section of Gastroenterology, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
| | - Ilaria Saracino
- Department of Clinical Medicine, University of Bologna, Bologna, Italy
| | - Cristina Zaccaro
- Department of Clinical Medicine, University of Bologna, Bologna, Italy
| | - Cesare Hassan
- Gastroenterology and Digestive Endoscopy, 'Nuovo Regina Margherita' Hospital, Rome, Italy
| | - Enzo Ierardi
- Section of Gastroenterology, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
| | - Alfredo Di Leo
- Section of Gastroenterology, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
| | - Giulia Fiorini
- Department of Clinical Medicine, University of Bologna, Bologna, Italy
| | | | - Giovanna Lo Re
- Department of Clinical Medicine, University of Bologna, Bologna, Italy
| | - Dino Vaira
- Department of Clinical Medicine, University of Bologna, Bologna, Italy
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Validation of a fluorescence in situ hybridization method using peptide nucleic acid probes for detection of Helicobacter pylori clarithromycin resistance in gastric biopsy specimens. J Clin Microbiol 2013; 51:1887-93. [PMID: 23596234 DOI: 10.1128/jcm.00302-13] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Here, we evaluated a previously established peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) method as a new diagnostic test for Helicobacter pylori clarithromycin resistance detection in paraffin-embedded gastric biopsy specimens. Both a retrospective study and a prospective cohort study were conducted to evaluate the specificity and sensitivity of a PNA-FISH method to determine H. pylori clarithromycin resistance. In the retrospective study (n = 30 patients), full agreement between PNA-FISH and PCR-sequencing was observed. Compared to the reference method (culture followed by Etest), the specificity and sensitivity of PNA-FISH were 90.9% (95% confidence interval [CI], 57.1% to 99.5%) and 84.2% (95% CI, 59.5% to 95.8%), respectively. In the prospective cohort (n = 93 patients), 21 cases were positive by culture. For the patients harboring clarithromycin-resistant H. pylori, the method showed sensitivity of 80.0% (95% CI, 29.9% to 98.9%) and specificity of 93.8% (95% CI, 67.7% to 99.7%). These values likely represent underestimations, as some of the discrepant results corresponded to patients infected by more than one strain. PNA-FISH appears to be a simple, quick, and accurate method for detecting H. pylori clarithromycin resistance in paraffin-embedded biopsy specimens. It is also the only one of the methods assessed here that allows direct and specific visualization of this microorganism within the biopsy specimens, a characteristic that allowed the observation that cells of different H. pylori strains can subsist in very close proximity in the stomach.
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Cerqueira L, Fernandes RM, Ferreira RM, Carneiro F, Dinis-Ribeiro M, Figueiredo C, Keevil CW, Azevedo NF, Vieira MJ. PNA-FISH as a new diagnostic method for the determination of clarithromycin resistance of Helicobacter pylori. BMC Microbiol 2011; 11:101. [PMID: 21569555 PMCID: PMC3112065 DOI: 10.1186/1471-2180-11-101] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 05/14/2011] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Triple therapy is the gold standard treatment for Helicobacter pylori eradication from the human stomach, but increased resistance to clarithromycin became the main factor of treatment failure. Until now, fastidious culturing methods are generally the method of choice to assess resistance status. In this study, a new genotypic method to detect clarithromycin resistance in clinical samples, based on fluorescent in situ hybridization (FISH) using a set of peptide nucleic acid probes (PNA), is proposed. RESULTS The set of probes targeting the point mutations responsible for clarithromycin resistance was applied to H. pylori suspensions and showed 100% sensitivity and specificity (95% CI, 79.9-100 and 95% CI, 71.6-100 respectively). This method can also be amenable for application to gastric biopsy samples, as resistance to clarithromycin was also detected when histological slides were tested. CONCLUSIONS The optimized PNA-FISH based diagnostic method to detect H. pylori clarithromycin resistance shown to be a very sensitive and specific method for the detection of clarithromycin resistance in the H. pylori smears and also proved to be a reliable method for the diagnosis of this pathogen in clinical samples and an alternative to existing plating methods.
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Affiliation(s)
- Laura Cerqueira
- IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar 4710-057, Braga, Portugal
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Barile KADS, Silva ALDCD, Xavier JN, Assumpção MB, Corvelo TCDO. Characterization of 23S rRNA domain V mutations in gastric biopsy patients from the eastern Amazon. Mem Inst Oswaldo Cruz 2010; 105:314-7. [PMID: 20512246 DOI: 10.1590/s0074-02762010000300012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Accepted: 03/05/2010] [Indexed: 01/25/2023] Open
Abstract
Resistance of Helicobacter pylori to clarithromycin is characterised by simple point mutations in the 23S ribosomal RNA (rRNA) gene and is responsible for the majority of cases of failure to eradicate this bacterium. In this paper, we characterised the variability of the 23S rRNA gene in biopsies of patients with gastric pathologies in the eastern Amazon (Northern Region of Brazil) using PCR and sequencing. A total of 49 sequences of H. pylori strains were analysed and of those, 75.6% presented nucleotide substitutions: A2142G (3.3%), T2182C (12.9%), G2224A (6.45%), T2215C (61.3%), A2192G (3.3%), G2204C (6.4%) and T2221C (6.4%). Of the mutations identified, four are known mutations related to cases of resistance and 16.1% are not yet described, revealing a high prevalence of mutations in the H. pylori 23S rRNA gene among the strains circulating in the in the eastern Amazon. The high prevalence in individuals with gastric pathologies in the Northern Region of Brazil demonstrates the need for characterising the profile of these strains to provide correct therapy for patients, considering that mutations in this gene are normally associated with resistance to the primary medication used in controlling H. pylori infection.
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Boyanova L, Mitov I. Geographic map and evolution of primary Helicobacter pylori resistance to antibacterial agents. Expert Rev Anti Infect Ther 2010; 8:59-70. [PMID: 20014902 DOI: 10.1586/eri.09.113] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Antibiotic resistance in Helicobacter pylori is the major cause of eradication failure. Primary H. pylori susceptibility patterns, however, are becoming less predictable. Currently, high (> or =20%) clarithromycin resistance rates have been observed in the USA and in developed countries in Europe and Asia, while the highest (> or =80%) metronidazole-resistance rates have been reported in Africa, Asia and South America. Primary quinolone-resistance rates of 10% or more have already been reported in developed countries in Europe and Asia. Primary amoxicillin resistance has been low (0 to <2%) in Europe but higher (6-59%) in Africa, Asia and South America. Similarly, tetracycline resistance has been absent or low (<5%) in most countries and higher (9-27%) in Asia and South America. The increasing clarithromycin and quinolone resistance, and multidrug resistance detected in 0 to less than 5% in Europe and more often (14.2%) in Brazil are worrying. Growing resistance often parallels national antibiotic consumption and may vary within patient groups according to the geographic region, patient's age and sex, type of disease, birthplace, other infections and other factors. The geographic map and evolution of primary H. pylori resistance are clinically important, should be considered when choosing eradication regimens, and should be monitored constantly at national and global levels in an attempt to reach the recently recommended goal of eradication of more than 95%.
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Affiliation(s)
- Lyudmila Boyanova
- Department of Medical Microbiology, Medical University of Sofia, Zdrave street 2, 1431 Sofia, Bulgaria.
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Alfaresi MS, Elkoush AA. Characterization of clarithromycin resistance in isolates of Helicobacter pylori from the UAE. Indian J Gastroenterol 2010; 29:116-20. [PMID: 20658326 DOI: 10.1007/s12664-010-0034-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Accepted: 01/07/2010] [Indexed: 02/04/2023]
Abstract
BACKGROUND Clarithromycin therapy is effective in eradicating Helicobacter pylori. However, the resistance of H. pylori to clarithromycin is increasingly reported. The present study aimed to characterize the types of mutations present in the 23S rRNA genes of isolates of clarithromycin-resistant H. pylori from the UAE. METHODS Clarithromycin susceptibility of H. pylori isolates (n = 26) was determined by E tests. Analyses for point mutations in domain V of the 23S rRNA genes in clarithromycin-resistant and-sensitive strains were performed by sequence analysis of amplified PCR products. RESULTS Out of 100 gastric antral biopsy samples, 26 were positive for H. pylori by culture, and 29 were positive by PCR. Of the 26 culture isolates, five (19.2%) were resistant to clarithromycin and 24 were sensitive. The MIC of the resistant strains ranged from 3 to 24 microg/mL (median 24). All of the clarithromycin-resistant isolates had point mutations in the 23S rRNA gene. Two isolates had an A2142G 23S rRNA mutation, and three had A2143G mutations. CONCLUSION Clarithromycin resistance was common in this small collection of H. pylori isolates from the UAE. The A2142G and A2143G mutations were associated with clarithromycin resistance.
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Affiliation(s)
- Mubarak S Alfaresi
- Department of Pathology and Laboratory Medicine, Zayed Military Hospital, Abu Dhabi, United Arab Emirates.
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Toledo H, Lopez-Solis R. Tetracycline resistance in Chilean clinical isolates of Helicobacter pylori. J Antimicrob Chemother 2009; 65:470-3. [DOI: 10.1093/jac/dkp457] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Ahmad N, Zakaria WR, Abdullah SA, Mohamed R. Characterization of clarithromycin resistance in Malaysian isolates of Helicobacter pylori. World J Gastroenterol 2009; 15:3161-5. [PMID: 19575497 PMCID: PMC2705740 DOI: 10.3748/wjg.15.3161] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To characterize the types of mutations present in the 23S rRNA genes of Malaysian isolates of clarithromycin-resistant Helicobacter pylori (H pylori).
METHODS: Clarithromycin susceptibility of H pylori isolates was determined by E test. Analyses for point mutations in the domain V of 23S rRNA genes in clarithromycin-resistant and -sensitive strains were performed by sequence analysis of amplified polymerase chain reaction products. Restriction fragment length polymorphism was performed using BsaI and MboII enzymes to detect restriction sites that correspond to the mutations in the clarithromycin-resistant strains.
RESULTS: Of 187 isolates from 120 patients, four were resistant to clarithromycin, while 183 were sensitive. The MIC of the resistant strains ranged from 1.5 to 24 &mgr;g/mL. Two isolates had an A2142G mutation and another two had A2143G mutations. A T2182C mutation was detected in two out of four clarithromycin-resistant isolates and in 13 of 14 clarithromycin-sensitive isolates. Restriction enzyme analyses with BsaI and MboII were able to detect the mutations.
CONCLUSION: Clarithromycin resistance is an uncommon occurrence among Malaysian isolates of H pylori strains and the mutations A2142G and A2143G detected were associated with low-level resistance.
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Jones KR, Cha JH, Merrell DS. Who's Winning the War? Molecular Mechanisms of Antibiotic Resistance in Helicobacter pylori. CURRENT DRUG THERAPY 2008; 3:190-203. [PMID: 21765819 DOI: 10.2174/157488508785747899] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The ability of clinicians to wage an effective war against many bacterial infections is increasingly being hampered by skyrocketing rates of antibiotic resistance. Indeed, antibiotic resistance is a significant problem for treatment of diseases caused by virtually all known infectious bacteria. The gastric pathogen Helicobacter pylori is no exception to this rule. With more than 50% of the world's population infected, H. pylori exacts a tremendous medical burden and represents an interesting paradigm for cancer development; it is the only bacterium that is currently recognized as a carcinogen. It is now firmly established that H. pylori infection is associated with diseases such as gastritis, peptic and duodenal ulceration and two forms of gastric cancer, gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT) lymphoma. With such a large percentage of the population infected, increasing rates of antibiotic resistance are particularly vexing for a treatment regime that is already fairly complicated; treatment consists of two antibiotics and a proton pump inhibitor. To date, resistance has been found to all primary and secondary lines of antibiotic treatment as well as to drugs used for rescue therapy.
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Affiliation(s)
- Kathleen R Jones
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD 20814, USA
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