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Kebotsamang T, Munkombwe D, Bwalya L, Kelly P, Kayamba V. Prevalence of Clarithromycin-Resistant Helicobacter pylori Strains in Zambia: A Sub-Saharan African Country. Dig Dis 2024; 42:154-160. [PMID: 38185098 PMCID: PMC10997253 DOI: 10.1159/000535454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/19/2023] [Indexed: 01/09/2024]
Abstract
INTRODUCTION Helicobacter pylori (H. pylori) is one of the most important infections globally, affecting more than 50% of the human population. Clarithromycin (CLA)-containing regimens are recommended for empirical eradication of H. pylori in populations with less than 15% resistance. The aim of this study was to estimate the prevalence of CLA resistance in samples collected from Zambian patients to determine if CLA is suitable for first-line H. pylori empirical treatment. METHODOLOGY We used archival biopsy samples collected from dyspeptic patients undergoing endoscopy. The samples had been snap-frozen immediately after collection and stored at -80°C. We performed multiplex real-time PCR using Bosphore Helicobacter pylori Genotyping Kits v1, Istanbul, Turkey, to determine the presence of wild-type H. pylori and three mutations, A2142G, A2142C, and A2143G, of domain V in 23s rRNA gene. RESULTS We tested 259 gastric biopsy samples from patients with dyspepsia, of which 136 (53%) were from females. The median age was 48 years (IQR 40-61 years). Endoscopically, most of the patients, 164 (63%), had a normal gastric mucosa. CLA resistance was found in 48 (28%) samples, with A2142G mutation in 23 (13%), A2143G mutation in 32 (18%), and double mutations A2142C and A2143G in 6 (3%). CONCLUSIONS The presence of significant levels of CLA resistance in Zambia suggests that it should not be used as first-line empirical treatment for H. pylori infection. However, with a limitation of suitable alternatives, there is an urgent need to formulate new treatment approaches.
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Affiliation(s)
| | | | - Lalusha Bwalya
- Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia
| | - Paul Kelly
- Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Violet Kayamba
- Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia
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Nguyen TC, Le GKN, Pham DTH, Pham BV, Nguyen LTH, Che TH, Nguyen HT, Truong DQ, Robert A, Bontems P, Nguyen PNV. Antibiotic resistance and heteroresistance in Helicobacter pylori isolates from symptomatic Vietnamese children: A prospective multicenter study. Helicobacter 2023; 28:e13009. [PMID: 37497797 DOI: 10.1111/hel.13009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/26/2023] [Accepted: 07/19/2023] [Indexed: 07/28/2023]
Abstract
BACKGROUND Antibiotic resistance of Helicobacter pylori (H. pylori) is increasing worldwide, with geographical variations, impacting the treatment outcomes. This study assessed the antibiotic resistance patterns of H. pylori in Vietnamese children. MATERIALS AND METHODS Symptomatic children undergoing gastroduodenoscopy at two tertiary Children's Hospitals in Ho Chi Minh City were recruited. Antral and corpus biopsies were obtained and cultured separately. Susceptibility to amoxicillin (AMO), clarithromycin (CLA), metronidazole (MET), levofloxacin (LEV), and tetracycline (TET) was determined using E-test. Polymerase chain reaction was performed on another antral biopsy to detect the urease gene, cytotoxin-associated gene A (cagA), vacuolating cytotoxin A (vacA) genotypes, and 23S rRNA mutations conferring CLA resistance. RESULTS Among 123 enrolled children, a high primary resistance rate was found for CLA (68.5%, 61/89), followed by LEV (55.1%), MET (31.5%), AMO (25.8%), and TET (1.1%). Secondary resistance rates were 82.1% (7/28), 71.4%, 53.6%, and 3.6% for CLA, LEV, MET, and TET, respectively. Multidrug resistance was frequent (67.7%), with common patterns including CLA + LEV (20.3%) and CLA + MTZ + LEV (15.2%). Heteroresistance was detected in eight children (6.5%). The A2143G mutation was detected in 97.5% (119/122) of children. 86.1% of children had positive cagA strains and 27.9% had multiple vacA genotypes. No factor was significantly associated with antibiotic resistance. CONCLUSIONS The alarming rate of antibiotic resistance for H. pylori, especially for CLA, with emerging multi- and hetero-resistant strains, pose a major treatment challenge that precludes CLA use as empirical therapy. Biopsies from both antrum and corpus can improve H. pylori culture, allowing tailored treatment based on antimicrobial susceptibility.
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Affiliation(s)
- Tu Cam Nguyen
- Department of Gastroenterology, City Children's Hospital, Ho Chi Minh City, Vietnam
- Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Giao Kim Ngoc Le
- Department of Microbiology and Parasitology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Dao Thi Hong Pham
- Department of Genetics, University of Science - Vietnam National University Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Bao Van Pham
- Department of Microbiology and Parasitology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Loan Thi Hong Nguyen
- Department of Gastroenterology, Children's Hospital 2, Ho Chi Minh City, Vietnam
| | - Thai Hoang Che
- Department of Biostatistics and Informatics, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam
| | - Hiep Thanh Nguyen
- Faculty of Public Health, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam
| | - Dinh Quang Truong
- Department of Surgery, City Children's Hospital, Ho Chi Minh City, Vietnam
| | - Annie Robert
- Institut de recherche expérimentale et clinique, Pôle d'épidémiologie et Biostatistique, Université catholique de Louvain, Brussels, Belgium
| | - Patrick Bontems
- Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
- Department of Gastroenterology, Hôpital Universitaire des Enfants Reine Fabiola, Brussels, Belgium
| | - Phuong Ngoc Van Nguyen
- Department of Biostatistics and Informatics, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam
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Monroy FP, Brown HE, Acevedo-Solis CM, Rodriguez-Galaviz A, Dholakia R, Pauli L, Harris RB. Antibiotic Resistance Rates for Helicobacter pylori in Rural Arizona: A Molecular-Based Study. Microorganisms 2023; 11:2290. [PMID: 37764134 PMCID: PMC10536767 DOI: 10.3390/microorganisms11092290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/29/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
Helicobacter pylori (H. pylori) is a common bacterial infection linked to gastric malignancies. While H. pylori infection and gastric cancer rates are decreasing, antibiotic resistance varies greatly by community. Little is known about resistance rates among rural Indigenous populations in the United States. From 2018 to 2021, 396 endoscopy patients were recruited from a Northern Arizona clinic, where community H. pylori prevalence is near 60%. Gastric biopsy samples positive for H. pylori (n = 67) were sequenced for clarithromycin- and metronidazole-associated mutations, 23S ribosomal RNA (23S), and oxygen-insensitive NADPH nitroreductase (rdxA) regions. Medical record data were extracted for endoscopic findings and prior H. pylori history. Data analysis was restricted to individuals with no history of H. pylori infection. Of 49 individuals, representing 64 samples which amplified in the 23S region, a clarithromycin-associated mutation was present in 38.8%, with T2182C being the most common mutation at 90%. While the prevalence of metronidazole-resistance-associated mutations was higher at 93.9%, the mutations were more variable, with D95N being the most common followed by L62V. No statistically significant sex differences were observed for either antibiotic. Given the risk of treatment failure with antibiotic resistance, there is a need to consider resistance profile during treatment selection. The resistance rates in this population of American Indian patients undergoing endoscopy are similar to other high-risk populations. This is concerning given the high H. pylori prevalence and low rates of resistance testing in clinical settings. The mutations reported are associated with antibiotic resistance, but clinical resistance must be confirmed.
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Affiliation(s)
- Fernando P. Monroy
- Department of Biological Sciences, College of the Environment, Forestry and Natural Sciences, Northern Arizona University, 617 South Beaver Street, Flagstaff, AZ 86011, USA
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Heidi E. Brown
- Department of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, 1295 N Martin Ave, Tucson, AZ 85724, USA (R.B.H.)
| | - Claudia M. Acevedo-Solis
- Department of Biological Sciences, College of the Environment, Forestry and Natural Sciences, Northern Arizona University, 617 South Beaver Street, Flagstaff, AZ 86011, USA
| | - Andres Rodriguez-Galaviz
- Department of Biological Sciences, College of the Environment, Forestry and Natural Sciences, Northern Arizona University, 617 South Beaver Street, Flagstaff, AZ 86011, USA
| | - Rishi Dholakia
- Winslow Indian Health Care Center, 500 North Indiana Avenue, Winslow, AZ 86047, USA (L.P.)
| | - Laura Pauli
- Winslow Indian Health Care Center, 500 North Indiana Avenue, Winslow, AZ 86047, USA (L.P.)
| | - Robin B. Harris
- Department of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, 1295 N Martin Ave, Tucson, AZ 85724, USA (R.B.H.)
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Alavifard H, Nabavi-Rad A, Baghaei K, Sadeghi A, Yadegar A, Zali MR. Pyrosequencing analysis for rapid and accurate detection of clarithromycin resistance-associated mutations in Iranian Helicobacter pylori isolates. BMC Res Notes 2023; 16:136. [PMID: 37415212 DOI: 10.1186/s13104-023-06420-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 06/27/2023] [Indexed: 07/08/2023] Open
Abstract
BACKGROUND Treatment of Helicobacter pylori (H. pylori) infection has become challenging following the development of primary antibiotic resistance. A primary therapeutic regimen for H. pylori eradication includes clarithromycin; however, the presence of point mutations within the 23S rRNA sequence of H. pylori contributes to clarithromycin resistance and eradication failure. Thus, we aimed to develop a rapid and precise method to determine clarithromycin resistance-related point mutations using the pyrosequencing method. METHODS AND RESULTS H. pylori was isolated from 82 gastric biopsy samples and minimal inhibitory concentration (MIC) was evaluated using the agar dilution method. Clarithromycin resistance-associated point mutations were detected by Sanger sequencing, from which 11 isolates were chosen for pyrosequencing. Our results demonstrated a 43.9% (36/82) prevalence in resistance to clarithromycin. The A2143G mutation was detected in 8.3% (4/48) of H. pylori isolates followed by A2142G (6.2%), C2195T (4.1%), T2182C (4.1%), and C2288T (2%). Although the C2195T mutation was only detected by Sanger sequencing, the overall results from pyrosequencing and Sanger sequencing platforms were comparable. CONCLUSIONS Pyrosequencing could be used as a rapid and practical platform in clinical laboratories to determine the susceptibility profile of H. pylori isolates. This might pave the way for efficient H. pylori eradication upon detection.
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Affiliation(s)
- Helia Alavifard
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ali Nabavi-Rad
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kaveh Baghaei
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Sadeghi
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Yadegar
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Mohammad Reza Zali
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Lormohammadi L, Nikkhahi F, Bolori S, Karami AA, Hajian S, Rad N, Peymani A, Samimi R. High level of resistance to metronidazole and clarithromycin among Helicobacter pylori clinical isolates in Qazvin province, Iran. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2022.101494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Park CG, Kim S, Jeon HS, Han S. Validation of loop-mediated isothermal amplification to detect Helicobacter pylori and 23S rRNA mutations: A prospective, observational clinical cohort study. J Clin Lab Anal 2020; 35:e23563. [PMID: 32893424 PMCID: PMC7843275 DOI: 10.1002/jcla.23563] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/13/2020] [Accepted: 05/19/2020] [Indexed: 12/15/2022] Open
Abstract
Background Identifying point mutations in 23S rRNA closely associated with clarithromycin resistance can increase the eradication rate of Helicobacter pylori (H pylori). In this study, we verified the sensitivity, specificity, and reliability of a newly developed loop‐mediated isothermal amplification (LAMP) assay kit to detect H pylori and 2143G and 2182C mutations in 23S rRNA. Methods LAMP assay to detect H pylori and a mutant strain with 2143G and 2182C was conducted with the Isopollo®H pylori & ClaR kit. A prospective, open‐label, observational study was conducted to validate the reliability of the LAMP assay in both a development cohort and a bedside direct LAMP cohort. Results The LAMP assay had good sensitivity, as it could detect as few as 10–100 copies of H pylori and mutants with 2143G and 2182C in 23S rRNA, and good specificity, as it did not react with other bacterial species. In the development cohort with 622 participants, the LAMP assay showed good agreement with RUT for detecting H pylori (kappa value 0.923, P < .001) and had exactly the same results as sequencing analysis for 2143G and 2182C point mutations. The direct LAMP cohort including 93 patients had 97.7% (42/43) of concordance in detecting 2143G and 2182C point mutations compared to the PCR‐based sequencing analysis. Conclusion The Isopollo®H pylori & ClaR LAMP assay was a valid method for detecting H pylori and for 2143G and 2182C point mutations in 23S rRNA in a clinical setting.
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Affiliation(s)
- Chang-Geun Park
- Department of Internal Medicine, Daegu Fatima Hospital, Daegu, Korea
| | | | | | - Seungwoo Han
- Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea
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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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Santos-Cortez RLP, Bhutta MF, Earl JP, Hafrén L, Jennings M, Mell JC, Pichichero ME, Ryan AF, Tateossian H, Ehrlich GD. Panel 3: Genomics, precision medicine and targeted therapies. Int J Pediatr Otorhinolaryngol 2020; 130 Suppl 1:109835. [PMID: 32007292 PMCID: PMC7155947 DOI: 10.1016/j.ijporl.2019.109835] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE To review the most recent advances in human and bacterial genomics as applied to pathogenesis and clinical management of otitis media. DATA SOURCES PubMed articles published since the last meeting in June 2015 up to June 2019. REVIEW METHODS A panel of experts in human and bacterial genomics of otitis media was formed. Each panel member reviewed the literature in their respective fields and wrote draft reviews. The reviews were shared with all panel members, and a merged draft was created. The panel met at the 20th International Symposium on Recent Advances in Otitis Media in June 2019, discussed the review and refined the content. A final draft was made, circulated, and approved by the panel members. CONCLUSION Trans-disciplinary approaches applying pan-omic technologies to identify human susceptibility to otitis media and to understand microbial population dynamics, patho-adaptation and virulence mechanisms are crucial to the development of novel, personalized therapeutics and prevention strategies for otitis media. IMPLICATIONS FOR PRACTICE In the future otitis media prevention strategies may be augmented by mucosal immunization, combination vaccines targeting multiple pathogens, and modulation of the middle ear microbiome. Both treatment and vaccination may be tailored to an individual's otitis media phenotype as defined by molecular profiles obtained by using rapidly developing techniques in microbial and host genomics.
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Affiliation(s)
- Regie Lyn P. Santos-Cortez
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, 12700 E. 19 Ave., Aurora, CO 80045, USA
| | - Mahmood F. Bhutta
- Department of ENT, Royal Sussex County Hospital, Eastern Road, Brighton BN2 5BE, UK
| | - Joshua P. Earl
- Center for Genomic Sciences, Institute for Molecular Medicine and Infectious Disease; Department of Microbiology and Immunology; Drexel University College of Medicine, 245 N. 15 St., Philadelphia, PA 19102, USA
| | - Lena Hafrén
- Department of Otorhinolaryngology, Head & Neck Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Tukholmankatu 8A, 00290 Helsinki, Finland
| | - Michael Jennings
- Institute for Glycomics, Gold Coast campus, Griffith University, QLD 4222, Australia
| | - Joshua C. Mell
- Center for Genomic Sciences, Institute for Molecular Medicine and Infectious Disease; Department of Microbiology and Immunology; Drexel University College of Medicine, 245 N. 15 St., Philadelphia, PA 19102, USA
| | - Michael E. Pichichero
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, 1425 Portland Ave., Rochester, NY 14621, USA
| | - Allen F. Ryan
- Department of Surgery/Otolaryngology, University of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA
| | - Hilda Tateossian
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell, Oxford, Didcot OX11 0RD, UK
| | - Garth D. Ehrlich
- Center for Genomic Sciences, Institute for Molecular Medicine and Infectious Disease; Department of Microbiology and Immunology; Drexel University College of Medicine, 245 N. 15 St., Philadelphia, PA 19102, USA
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Palmitessa V, Monno R, Panarese A, Cuppone R, Burattini O, Marangi S, Curlo M, Fumarola L, Petrosillo A, Parisi A, Capozzi L, Bianco A, Lippolis A. Evaluation of Antibiotic Resistance of Helicobacter pylori Strains Isolated in Bari, Southern Italy, in 2017-2018 by Phenotypic and Genotyping Methods. Microb Drug Resist 2020; 26:909-917. [PMID: 32101078 DOI: 10.1089/mdr.2019.0262] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Objective: Helicobacter pylori antibiotic resistance is a constantly evolving process and local surveillance is warranted to guide clinicians in the choice of therapy. Materials and Methods: Antibiotic susceptibility testing was performed by E-test on 92 H. pylori strains, and resistance to clarithromycin and levofloxacin was also evaluated using a commercially available genotyping method. Results: In naïve patients the resistance to clarithromycin, levofloxacin, and metronidazole was 37.7%, 26.2%, and 16.4%, respectively, significantly lower than the percentage found in treated patients. Concomitant resistance to ≥2 antibiotics was also observed in naïve patients. The A2143G mutation of the 23S-rRNA gene was the most frequently detected, also in naïve patients. The highest minimum inhibitory concentration (MIC)50 value (256 mg/L) was associated with A2142 mutations in all the patients carrying them. For levofloxacin resistance a mutation in codon 87 was detected in 63.9% and in codon 91 in 36.1% of the H. pylori strains, without significant differences in the patients groups. A mutation in codon 87 was associated with the highest MIC50 value (32 mg/L). Conclusions: In our area, a high prevalence of H. pylori primary resistance was detected; these rates were higher in patients who had experienced failure of several courses of therapy. A better knowledge of the local epidemiology of resistance, and the genotypes responsible, will improve the H. pylori eradication rates.
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Affiliation(s)
- Valeria Palmitessa
- Laboratory of Microbiology and Virology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy
| | - Rosa Monno
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro," Bari, Italy
| | - Alba Panarese
- Department of Gastroenterology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy
| | - Renato Cuppone
- Department of Gastroenterology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy
| | - Osvaldo Burattini
- Department of Gastroenterology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy
| | - Stefania Marangi
- Department of Gastroenterology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy
| | - Margherita Curlo
- Department of Gastroenterology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy
| | - Luciana Fumarola
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro," Bari, Italy
| | - Antonella Petrosillo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro," Bari, Italy
| | - Antonio Parisi
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, Sezione di Putignano, Bari, Italy
| | - Loredana Capozzi
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, Sezione di Putignano, Bari, Italy
| | - Angelica Bianco
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, Sezione di Putignano, Bari, Italy
| | - Antonio Lippolis
- Laboratory of Microbiology and Virology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy
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Saranathan R, Levi MH, Wattam AR, Malek A, Asare E, Behin DS, Pan DH, Jacobs WR, Szymczak WA. Helicobacter pylori Infections in the Bronx, New York: Surveying Antibiotic Susceptibility and Strain Lineage by Whole-Genome Sequencing. J Clin Microbiol 2020; 58:e01591-19. [PMID: 31801839 PMCID: PMC7041580 DOI: 10.1128/jcm.01591-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/27/2019] [Indexed: 12/16/2022] Open
Abstract
The emergence of drug resistance in Helicobacter pylori has resulted in a greater need for susceptibility-guided treatment. While the alleles associated with resistance to clarithromycin and levofloxacin have been defined, there are limited data regarding the molecular mechanisms underlying resistance to other antimicrobials. Using H. pylori isolates from 42 clinical specimens, we compared phenotypic and whole-genome sequencing (WGS)-based detection of resistance. Phenotypic resistance correlated with the presence of alleles of 23S rRNA (A2142G/A2143G) for clarithromycin (kappa coefficient, 0.84; 95% confidence interval [CI], 0.67 to 1.0) and gyrA (N87I/N87K/D91Y/D91N/D91G/D99N) for levofloxacin (kappa coefficient, 0.90; 95% CI, 0.77 to 1.0). Phenotypic resistance to amoxicillin in three isolates correlated with mutations in pbp1, pbp2, and/or pbp3 within coding regions near known amoxicillin binding motifs. All isolates were phenotypically susceptible to tetracycline, although four bore a mutation in 16S rRNA (A926G). For metronidazole, nonsense mutations and R16H substitutions in rdxA correlated with phenotypic resistance (kappa coefficient, 0.76; 95% CI, 0.56 to 0.96). Previously identified mutations in the rpoB rifampin resistance-determining region (RRDR) were not present, but 14 novel mutations outside the RRDR were found in rifampin-resistant isolates. WGS also allowed for strain lineage determination, which may be important for future studies in associating precise MICs with specific resistance alleles. In summary, WGS allows for broad analyses of H. pylori isolates, and our findings support the use of WGS for the detection of clarithromycin and levofloxacin resistance. Additional studies are warranted to better define mutations conferring resistance to amoxicillin, tetracycline, and rifampin, but combinatorial analyses for rdxA gene truncations and R16H mutations have utility for determining metronidazole resistance.
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Affiliation(s)
- Rajagopalan Saranathan
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Michael H Levi
- Department of Pathology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - Alice R Wattam
- Biocomplexity Institute and Initiative, University of Virginia, Charlottesville, Virginia, USA
| | - Adel Malek
- Provincial Public Health Laboratory, Eastern Health Microbiology Services, St. John's, New Foundland and Labrador, Canada
| | - Emmanuel Asare
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
- Department of Pathology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - Daniel S Behin
- Department of Medicine, Division of Gastroenterology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - Debra H Pan
- Department of Pediatrics, Division of Gastroenterology and Nutrition, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - William R Jacobs
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Wendy A Szymczak
- Department of Pathology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
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Gao C, Du SY, Fang L, Fan YH, Song AP, Chen H. Eradication Treatment of Helicobacter pylori Infection Based on Molecular Pathologic Antibiotic Resistance. Infect Drug Resist 2020; 13:69-79. [PMID: 32021321 PMCID: PMC6954831 DOI: 10.2147/idr.s232169] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/17/2019] [Indexed: 12/11/2022] Open
Abstract
Background Unfortunately, the eradication rate of Helicobacter pylori (H. pylori) treatment is markedly decreasing in recent years and the major reason is antibiotic resistance. Our study was designed to determine the effect and safety of H. pylori eradication treatment based on the molecular pathologic antibiotic resistance. Methods 261 patients were analyzed retrospectively, including 111 patients who were treated for the first time (one group as First-treated) and 150 patients who failed at least once in bismuth quadruple therapy (another group as Re-treatment). Antibiotic resistance was examined by Real-time PCR detection and conventional PCR and sequencing method. The eradication rate (ER) was compared per intention to treat (ITT) and per protocol (PP) between the two groups. Results The resistance rates to amoxicillin, clarithromycin, fluoroquinolone and tetracycline were 5.5%, 42.1%, 41.7% and 12.9% in the 111 first-treated patients, and 11.7%, 79.7%, 70.7% and 30.0% in the 150 re-treatment patients. The ERs in the ITT and PP analyses were 92.79% (95% CI, 87.98–97.60%, n=111) and 98.10% (95% CI, 95.48–100%, n=105), respectively, in the first-treated patients and 90.67% (95% CI, 86.01–95.32%, n=150) and 95.10% (95% CI, 91.57–98.64%, n=143), respectively, in the re-treatment patients. No significant differences were shown in the ERs between two group patients, and no serious adverse events were found. Conclusion H. pylori eradication treatment based on molecular pathologic antibiotic resistance showed good effect and safety in both first and re-treated patients.
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Affiliation(s)
- Chun Gao
- Department of Gastroenterology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, People's Republic of China
| | - Shi-Yu Du
- Department of Gastroenterology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, People's Republic of China
| | - Long Fang
- Department of Gastroenterology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, People's Republic of China
| | - Yan-Hua Fan
- Department of Gastroenterology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, People's Republic of China
| | - Ai-Ping Song
- Department of Pathology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, People's Republic of China
| | - Huang Chen
- Department of Pathology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, People's Republic of China
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Helicobacter pylori Eradication According to Sequencing-Based 23S Ribosomal RNA Point Mutation Associated with Clarithromycin Resistance. J Clin Med 2019; 9:jcm9010054. [PMID: 31881688 PMCID: PMC7019680 DOI: 10.3390/jcm9010054] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 12/19/2019] [Accepted: 12/23/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND/AIMS Clarithromycin resistance in Helicobacter pylori is associated with point mutations in the 23S ribosomal RNA (rRNA) gene. We investigated the point mutations in the 23S rRNA genes of patients with clarithromycin-resistant H. pylori and compared the H. pylori eradication rates based on the point mutations. METHODS A total of 431 adult patients with H. pylori infection were recruited in Kangdong Sacred Heart Hospital in 2017 and 2018. Patients who did not have point mutations related to clarithromycin resistance and/or had clinically insignificant point mutations were treated with PAC (proton pump inhibitor, amoxicillin, clarithromycin) for seven days, while patients with clinically significant point mutations were treated with PAM (proton pump inhibitor, amoxicillin, metronidazole) for seven days. H. pylori eradication rates were compared. RESULTS Sequencing-based detection of point mutations identified four mutations that were considered clinically significant (A2142G, A2142C, A2143G, A2143C). The clarithromycin resistance rate was 21.3% in the overall group of patients. A2143G was the most clinically significant point mutation (84/431, 19.5%), while T2182C was the most clinically insignificant point mutation (283/431, 65.7%). The overall H. pylori eradication rate was 83.7%, and the seven-day PAM-treated clarithromycin-resistance group showed a significantly lower eradication rate than the seven-day PAC-treated nonresistance group (ITT; 55.4% (51/92) vs. 74.3% (252/339), p = 0.001, PP; 66.2% (51/77) vs. 88.4% (252/285), p = 0.0001). CONCLUSIONS There were significantly lower eradication rates in the patients with clarithromycin-resistant H. pylori when treated with PAM for seven days. A future study comparing treatment regimens in clarithromycin-resistant H. pylori-infected patients may be necessary.
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Choi YI, Chung JW, Park DK, Kim KO, Kwon KA, Kim YJ, Seo JY. Tailored eradication vs empirical bismuth-containing quadruple therapy for first-line Helicobacter pylori eradication: A comparative, open trial. World J Gastroenterol 2019; 25:6743-6751. [PMID: 31857776 PMCID: PMC6920661 DOI: 10.3748/wjg.v25.i46.6743] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/30/2019] [Accepted: 12/06/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Few studies have compared the efficacy and safety profile of a tailored eradication (TR) strategy based on the presence of a 23S ribosomal RNA point mutation with those of empirical bismuth-based quadruple therapy (EBQT) for first-line eradication of Helicobacter pylori (H. pylori) in Korean patients.
AIM To compare the efficacy and safety of a TR strategy and those of EBQT regimen as first-line eradication therapy for H. pylori.
METHODS This is an open-label, comparative study in which we prospectively enrolled patients over 18 years of age with H. pylori infection and retrospectively reviewed their data. H. pylori-positive patients diagnosed by rapid urease test, Giemsa staining, or dual priming oligonucleotide polymerase chain reaction (DPO-PCR) were enrolled from May 2016 to September 2018 at Gil Medical Center. Patients with H. pylori infection received either a TR regimen or the EBQT regimen. In the tailored therapy group that underwent DPO-PCR testing, patients with A2142G and/or A2143G point mutations were treated with a bismuth-containing quadruple regimen. The eradication rate, patient-reported side effect rate, and H. pylori eradication success rate were evaluated and compared between the groups.
RESULTS A total of 150 patients were assigned to the TR (n = 50) or EBQT group (n = 100). The first-line eradication rate of H. pylori did not differ between the groups (96.0% vs 95.7%, P = 0.9). The rate of eradication-related side effects for TR was 12.0%, which differed significantly from that of EBQT (43.0%) for first-line treatment (P < 0.001).
CONCLUSION DPO-PCR-based TR for H. pylori eradication may be equally efficacious, with less treatment-related complications, compared to EBQT in Korea, where clarithromycin resistance is high.
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Affiliation(s)
- Youn I Choi
- Department of Gastroenterology, Gil Medical Center, Gachon University, Incheon 21565, South Korea
| | - Jun Won Chung
- Department of Gastroenterology, Gil Medical Center, Gachon University, Incheon 21565, South Korea
| | - Dong Kyun Park
- Department of Gastroenterology, Gil Medical Center, Gachon University, Incheon 21565, South Korea
| | - Kyoung Oh Kim
- Department of Gastroenterology, Gil Medical Center, Gachon University, Incheon 21565, South Korea
| | - Kwang An Kwon
- Department of Gastroenterology, Gil Medical Center, Gachon University, Incheon 21565, South Korea
| | - Yoon Jae Kim
- Department of Gastroenterology, Gil Medical Center, Gachon University, Incheon 21565, South Korea
| | - Ja Young Seo
- Department of Laboratory Medicine, Gil Medical Center, Gachon University, Incheon 21565, South Korea
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Abstract
PURPOSE OF REVIEW Helicobacter pylori eradication has become more challenging over the past decade due to increasing antimicrobial resistance, especially to clarithromycin and levofloxacin. We identified 508 recent publications on H. pylori treatment (published between January 2018 and June 2019), focusing on the most highly clinically relevant for this review. RECENT FINDINGS Declining H. pylori eradication rates with clarithromycin triple therapy have led to most guidelines recommending 14 days bismuth-based quadruple therapy or concomitant therapy as the best initial empiric regimen. Substituting amoxicillin for tetracycline or metronidazole in quadruple therapy, and a three-in-one pill version of the regimen, also appear effective. Vonoprazan, a potent acid inhibitor, can overcome much clarithromycin resistance in triple therapy. High-dose dual therapy (proton pump inhibitor with amoxicillin) is a promising alternative approach. Reviewing resistance patterns to select suitable first-line empiric therapies is important in high resistance regions. Molecular methods to evaluate H. pylori antimicrobial susceptibility promise to be simpler than standard microbiological culture. The cost-effectiveness of antimicrobial susceptibility testing in refractory cases remains unproven. SUMMARY Updating clinicians treating H. pylori is important to combat the emerging problems of multidrug antimicrobial resistance in H. pylori strains. Truly novel approaches to H. pylori eradication are needed.
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Ong S, Kim SE, Kim JH, Yi NH, Kim TY, Jung K, Park MI, Jung HY. Helicobacter pylori eradication rates with concomitant and tailored therapy based on 23S rRNA point mutation: A multicenter randomized controlled trial. Helicobacter 2019; 24:e12654. [PMID: 31411793 DOI: 10.1111/hel.12654] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 07/01/2019] [Accepted: 07/14/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND We evaluated the efficacy of tailored therapy based on point mutation presence identified with the dual-priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) method compared with concomitant therapy. MATERIALS AND METHODS Subjects were randomly assigned concomitant therapy (amoxicillin 1 g, clarithromycin 500 mg, metronidazole 500 mg, and lansoprazole 30 mg twice/day for 14 days) or tailored therapy (amoxicillin 1 g, clarithromycin 500 mg, and lansoprazole 30 mg twice/day for 14 days in point mutation-negative subjects; and amoxicillin 1 g, metronidazole 500 mg, and lansoprazole 30 mg twice/day for 14 days in point mutation-positive subjects). RESULTS A total of 397 and 352 subjects were included in the intention-to-treat (ITT) and per-protocol (PP) analyses, respectively. Point mutations were identified in 25.9% of the subjects. The overall eradication rate was not significantly different between the groups by ITT (86.2% vs 81.6%, P = .132) and PP analyses (90.2% vs 86.5%, P = .179). There was no significant difference in the eradication rates between the groups in both the point mutation-negative subjects (91.7% vs 87.3%, P = .154) and the point mutation-positive subjects (71.2% vs 64.7%, P = .312). The eradication rates were significantly lower in the point mutation-positive subjects than in the point mutation-negative subjects in both the concomitant and tailored therapy groups. CONCLUSIONS Tailored therapy based on point mutation presence identified with the DPO-based multiplex PCR method was as effective as concomitant therapy. The eradication rates of both therapy regimens were suboptimal in point mutation-positive subjects.
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Affiliation(s)
- Sungmoon Ong
- Department of Gastroenterology, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Sung Eun Kim
- Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea
| | - Ji Hyun Kim
- Department of Gastroenterology, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Nam Hee Yi
- Department of Gastroenterology, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Tae Young Kim
- Department of Gastroenterology, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Kyoungwon Jung
- Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea
| | - Moo In Park
- Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea
| | - Hwoon-Yong Jung
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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Fernández Salazar L, Valle Muñoz J. Treating Helicobacter pylori infection in the face of growing antibiotic resistance. REVISTA ESPANOLA DE ENFERMEDADES DIGESTIVAS 2019; 111:653-654. [PMID: 31476871 DOI: 10.17235/reed.2019.6575/2019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Helicobacter pylori eradication cures most peptic ulcers and non-atrophic chronic gastritis, and may potentially prevent over 70% of gastric cancers. In the late 1980s, shortly after the discovery of H. pylori, eradication therapy was established based on the use of two antibiotics (amoxicillin and clarithromycin) and one proton-pump inhibitor for 7 or 10 days (OCA7, OCA10). This therapy, recommended during the first Maastricht Consensus Conference, obtained eradication rates above 90%, and was equally effective everywhere around the world. However, over time, H. pylori has developed resistance to several antibiotics.
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Boltin D, Ashorov O, Benejat L, Hamouda D, Belfer RG, Niv Y, Dickman R, Perets TT. Novel high resolution melt curve assay for the analysis of predominance of Helicobacter pylori clarithromycin resistance. Pathog Dis 2019; 77:5543216. [DOI: 10.1093/femspd/ftz042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 07/31/2019] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
Clarithromycin resistance is the most common cause of Helicobacter pylori treatment failure and it is attributed to three point mutations, A2142G, A2142C and A2143G, within the 23S rRNA gene. We aimed to determine the prevalence of H. pylori clarithromycin resistance using a novel high resolution melt assay. A total of 151 stool samples were collected from treatment-naïve patients with general gastric discomfort who also performed 13CO2 breath tests. Stool antigen tests were also performed on 126 of the 151 stool samples collected. Bacterial DNA was extracted from the stool and analyzed by comparing it with four reference plasmids incorporating the three mutations and the wild type (WT) sequences. The melt assay detected 106 H. pylori positive samples, of which 54 had a WT sequence, and 52 had a point mutation associated with clarithromycin resistance, including A2142G in 10, A2142C in 13, A2143G in 18 and heterozygosity (multiple peaks) in 11. Compared with the gold standards (13CO2 breath and stool antigen tests), the melt assay had a sensitivity of 100% and 99% and a specificity of 82% and 78%, respectively. Therefore, our stool-based molecular assay is able to identify H. pylori infection and clarithromycin resistance. It could be used for screening prior to administration of clarithromycin eradication therapy.
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Affiliation(s)
- Doron Boltin
- Gastroenterology Laboratory and the Division of Gastroenterology, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Olga Ashorov
- Gastroenterology Laboratory and the Division of Gastroenterology, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel
| | - Lucie Benejat
- Centre National de Référence des Campylobacters et Hélicobacters, Laboratoire de Bactériologie, CHU Pellegrin, Bordeaux, France
| | - Dalal Hamouda
- Gastroenterology Laboratory and the Division of Gastroenterology, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel
| | - Rachel Gingold Belfer
- Gastroenterology Laboratory and the Division of Gastroenterology, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yaron Niv
- Gastroenterology Laboratory and the Division of Gastroenterology, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ram Dickman
- Gastroenterology Laboratory and the Division of Gastroenterology, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Tsachi Tsadok Perets
- Gastroenterology Laboratory and the Division of Gastroenterology, Rabin Medical Center, Beilinson Campus, Petach Tikva, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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