Azzaya Dashdorj, Gantuya Boldbaatar, Oyuntsetseg Khasag, Davaadorj Duger, Matsumoto Takashi, Akada Junko, Yamaoka Yoshio
Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Yufu City, Oita 879-5593, Japan.
Department of Gastroenterology, Mongolian National University of Medical Sciences, Ulaanbaatar 14210, Mongolia.
Microorganisms. 2020 Jul 16;8(7):1062. doi: 10.3390/microorganisms8071062.
Mongolia has a high prevalence of infection and the second highest incidence of gastric cancer worldwide. Thus, investigating the prevalence of antibiotic resistance and its underlying genetic mechanism is necessary. We isolated 361 strains throughout Mongolia. Agar dilution assays were used to determine the minimum inhibitory concentrations of five antibiotics; amoxicillin, clarithromycin, metronidazole, levofloxacin, and minocycline. The genetic determinants of antibiotic resistance were identified with next-generation sequencing (NGS) and the CLC Genomics Workbench. The resistance to metronidazole, levofloxacin, clarithromycin, amoxicillin, and minocycline was 78.7%, 41.3%, 29.9%, 11.9% and 0.28%, respectively. Multidrug resistance was identified in 51.3% of the isolates investigated which were further delineated into 9 antimicrobial resistance profiles. A number of known antibiotic resistance mutations were identified including , (missense, frameshift), (N87K, A88P, D91G/N/Y), 23S rRNA (A2143G), (N562Y), and 16S rRNA (A928C). Furthermore, we detected previously unreported mutations in (L610*) and the 23S rRNA gene (A1410G, C1707T, A2167G, C2248T, and C2922T). The degree of antibiotic resistance was high, indicating the insufficiency of standard triple therapy in Mongolia.
蒙古国感染率很高，胃癌发病率位居全球第二。因此，有必要调查抗生素耐药性的流行情况及其潜在的遗传机制。我们在蒙古国各地分离出361株菌株。采用琼脂稀释法测定阿莫西林、克拉霉素、甲硝唑、左氧氟沙星和米诺环素这五种抗生素的最低抑菌浓度。利用下一代测序（NGS）和CLC基因组工作台鉴定抗生素耐药性的遗传决定因素。对甲硝唑、左氧氟沙星、克拉霉素、阿莫西林和米诺环素的耐药率分别为78.7%、41.3%、29.9%、11.9%和0.28%。在所调查的分离株中，51.3%被鉴定为多重耐药，这些分离株进一步被划分为9种抗菌耐药谱。鉴定出许多已知的抗生素耐药性突变，包括 、 （错义、移码）、 （N87K、A88P、D91G/N/Y）、23S rRNA（A2143G）、 （N562Y）和16S rRNA（A928C）。此外，我们在 （L610*）和23S rRNA基因（A1410G、C1707T、A2167G、C2248T和C2922T）中检测到以前未报告的突变。抗生素耐药程度很高，这表明蒙古国标准三联疗法存在不足。
