{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T08:56:13Z","timestamp":1783587373953,"version":"3.55.0"},"reference-count":50,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2017,5,3]]},"abstract":"Helicobacter pylori<\/jats:italic> antibiotic susceptibility in the Dominican Republic has not been monitored. We assessed H. pylori<\/jats:italic> antibiotic susceptibility in the Dominican Republic, and analyzed H. pylori<\/jats:italic> mutations associated with antibiotic resistance. We recruited 158 dyspeptic patients in Santo Domingo and used agar dilution to test susceptibility to five antibiotics. Polymerase chain reaction\u2013based sequencing was used to assess gyrA<\/jats:italic>, gyrB<\/jats:italic>, rdxA<\/jats:italic>, frxA<\/jats:italic>, and 23S rRNA mutations; next-generation sequencing was used to identify other metronidazole resistance\u2013associated genes. Among 64 H. pylori<\/jats:italic> strains isolated, we identified two (3.1%), one (1.6%), and no strains with clarithromycin, amoxicillin, and tetracycline resistance, respectively. Moreover, high frequency of metronidazole resistance (53\/64, 82.8%) was observed, whereas levofloxacin resistance is emerging (23\/64, 35.9%). We identified many rdxA<\/jats:italic> and frxA<\/jats:italic> mutations in metronidazole-resistant strains, but no synergistic effect was apparent. We revealed novel mutations in dppA<\/jats:italic>, dppB<\/jats:italic>, fdxA<\/jats:italic>, and fdxB<\/jats:italic>, irrespective of rdxA<\/jats:italic> and frxA<\/jats:italic> mutations. Novel mutations at Ser-14 of trx1<\/jats:italic> and Arg-221 of dapF<\/jats:italic> were associated with different levels of metronidazole resistance. Most levofloxacin-resistant strains had a substitution at Asn-87 of gyrA<\/jats:italic>, including the strain with the highest levofloxacin resistance, whereas only three substitutions were found at Ser-479 of gyrB<\/jats:italic> with no synergistic effect. Besides the 23S rRNA A2142G mutation, we observed another mutation at T1958G in both clarithromycin-resistant strains. We confirmed high metronidazole and levofloxacin resistance associated with genetic mutations in the Dominican Republic. However, prevalence of clarithromycin resistance was low, suggesting that standard clarithromycin-based triple therapy remains useful as initial treatment of H. pylori<\/jats:italic> infection.<\/jats:p>","DOI":"10.4269\/ajtmh.16-0729","type":"journal-article","created":{"date-parts":[[2017,2,14]],"date-time":"2017-02-14T01:40:26Z","timestamp":1487036426000},"page":"1050-1059","source":"Crossref","is-referenced-by-count":14,"title":["Clarithromycin-Based Triple Therapy is Still Useful as an Initial Treatment for Helicobacter pylori Infection in the Dominican Republic"],"prefix":"10.4269","volume":"96","author":[{"given":"Muhammad","family":"Miftahussurur","sequence":"first","affiliation":[{"name":"Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan."},{"name":"Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, Texas."},{"name":"Gastroentero-Hepatology Division, Department of Internal Medicine, Faculty of Medicine-Dr. Soetomo Teaching Hospital-Institute of Tropical Disease, Universitas Airlangga, Surabaya, Indonesia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Modesto","family":"Cruz","sequence":"additional","affiliation":[{"name":"Institute of Microbiology and Parasitology, Faculty of Science, Autonomous University of Santo Domingo, Santo Domingo, Dominican Republic."},{"name":"Department of Biomedical Research, National Institute of Medicine and Diagnostic Imaging, Santo Domingo, Dominican Republic."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Phawinee","family":"Subsomwong","sequence":"additional","affiliation":[{"name":"Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9 A.","family":"Jim\u00e9nez Abreu","sequence":"additional","affiliation":[{"name":"Dominican\u2013Japanese Digestive Disease Center, Dr. Luis E. Aybar Health and Hygiene City, Santo Domingo, Dominican Republic."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Celso","family":"Hosking","sequence":"additional","affiliation":[{"name":"Institute of Microbiology and Parasitology, Faculty of Science, Autonomous University of Santo Domingo, Santo Domingo, Dominican Republic."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroyuki","family":"Nagashima","sequence":"additional","affiliation":[{"name":"Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junko","family":"Akada","sequence":"additional","affiliation":[{"name":"Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshio","family":"Yamaoka","sequence":"additional","affiliation":[{"name":"Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Japan."},{"name":"Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, Texas."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2795","reference":[{"key":"ref1","series-title":"J Gastroenterol Hepatol","first-page":"1587","article-title":"Second Asia-Pacific Consensus Guidelines for Helicobacter pylori infection","volume":"24","author":"Fock","year":"2009"},{"key":"ref2","series-title":"Gut","first-page":"646","article-title":"Management of Helicobacter pylori infection: the Maastricht IV\/ Florence Consensus Report","volume":"61","author":"Malfertheiner","year":"2012"},{"key":"ref3","series-title":"World J Gastroenterol","first-page":"9898","article-title":"Treatment of Helicobacter pylori infection: meeting the challenge of antimicrobial resistance","volume":"20","author":"Papastergiou","year":"2014"},{"key":"ref4","series-title":"Molecules","first-page":"6068","article-title":"Appropriate first-line regimens to combat Helicobacter pylori antibiotic resistance: an Asian perspective","volume":"20","author":"Miftahussurur","year":"2015"},{"key":"ref5","series-title":"BMC Gastroenterol","first-page":"164","article-title":"Low Helicobacter pylori primary resistance to clarithromycin in gastric biopsy specimens from dyspeptic patients of a city in the interior of Sao Paulo, Brazil","volume":"13","author":"Suzuki","year":"2013"},{"key":"ref6","series-title":"Helicobacter","first-page":"227","article-title":"Identification of a 23S rRNA gene mutation in clarithromycin-resistant Helicobacter pylori","volume":"1","author":"Stone","year":"1996"},{"key":"ref7","series-title":"Mol Microbiol","first-page":"383","article-title":"Metronidazole resistance in Helicobacter pylori is due to null mutations in a gene (rdxA) that encodes an oxygen-insensitive NADPH nitroreductase","volume":"28","author":"Goodwin","year":"1998"},{"key":"ref8","series-title":"J Bacteriol","first-page":"5082","article-title":"Sequential inactivation of rdxA (HP0954) and frxA (HP0642) nitroreductase genes causes moderate and high-level metronidazole resistance in Helicobacter pylori","volume":"182","author":"Jeong","year":"2000"},{"key":"ref9","series-title":"Antimicrob Agents Chemother","first-page":"2343","article-title":"Search for novel candidate mutations for metronidazole resistance in Helicobacter pylori using next-generation sequencing","volume":"59","author":"Binh","year":"2015"},{"key":"ref10","series-title":"World J Gastroenterol","first-page":"1847","article-title":"Screening for metronidazole-resistance associated gene fragments of H. pylori by suppression subtractive hybridization","volume":"13","author":"Li","year":"2007"},{"key":"ref11","series-title":"Biochem Biophys Res Commun","first-page":"785","article-title":"Isolation of a genetic locus associated with metronidazole resistance in Helicobacter pylori","volume":"236","author":"Chang","year":"1997"},{"key":"ref12","series-title":"J Bacteriol","first-page":"2927","article-title":"The fdxA ferredoxin gene can down-regulate frxA nitroreductase gene expression and is essential in many strains of Helicobacter pylori","volume":"185","author":"Mukhopadhyay","year":"2003"},{"key":"ref13","series-title":"Antimicrob Agents Chemother","first-page":"2133","article-title":"Analysis of rdxA and involvement of additional genes encoding NAD(P)H flavin oxidoreductase (FrxA) and ferredoxin-like protein (FdxB) in metronidazole resistance of Helicobacter pylori","volume":"44","author":"Kwon","year":"2000"},{"key":"ref14","series-title":"J Bacteriol","first-page":"1961","article-title":"Essential thioredoxin-dependent peroxiredoxin system from Helicobacter pylori: genetic and kinetic characterization","volume":"183","author":"Baker","year":"2001"},{"key":"ref15","series-title":"Curr Drug Ther","first-page":"190","article-title":"Who's winning the war? 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Hygiene"],"original-title":[],"link":[{"URL":"https:\/\/www.ajtmh.org\/view\/journals\/tpmd\/96\/5\/article-p1050.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.ajtmh.org\/downloadpdf\/journals\/tpmd\/96\/5\/article-p1050.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/www.ajtmh.org\/downloadpdf\/journals\/tpmd\/96\/5\/article-p1050.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,8,7]],"date-time":"2024-08-07T22:32:56Z","timestamp":1723069976000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ajtmh.org\/view\/journals\/tpmd\/96\/5\/article-p1050.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,5,3]]},"references-count":50,"journal-issue":{"issue":"5"},"URL":"https:\/\/doi.org\/10.4269\/ajtmh.16-0729","relation":{},"ISSN":["0002-9637","1476-1645"],"issn-type":[{"value":"0002-9637","type":"print"},{"value":"1476-1645","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,5,3]]}}}