Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
Health Clinical Sciences Research Center, Zahedan Branch, Islamic Azad University, Zahedan, Iran.
Biomed Res Int. 2020 Mar 27;2020:2304173. doi: 10.1155/2020/2304173. eCollection 2020.
is a common infectious bacterium mostly found in gastroduodenal diseases. The increased prevalence of clarithromycin-resistant strains is a major challenge in the successful treatment of infections caused by this organism. The present study is aimed at detecting the clarithromycin resistance pattern of strains isolated from gastric biopsies and evaluating point mutations of the 23S rRNA gene. . In the present descriptive cross-sectional study, 165 patients with gastrointestinal disorders, who were referred to the Endoscopy Center of Dr. Shariati Hospital of Isfahan, Iran, were enrolled from April to July 2018. infection was diagnosed by culture, and susceptibility of the isolates to clarithromycin was assessed by the E-test. Minimum inhibitory concentration (MIC) values were obtained based on EUCAST recommendations. Also, fluorescence in situ hybridization (FISH) was used to determine point mutations associated with clarithromycin resistance.
By using culturing, was isolated from 50.3% (83/165) gastric biopsy specimens. The overall frequency of resistance to clarithromycin was 25.3% (21/83) by the E-test. In the resistance genotypic analysis, 19 isolates had mutations. The prevalence of A2143G and A2144G mutations was 68.4% (13/19) and 31.5% (6/19), respectively. A2143C mutation was not tracked in any isolate. Two isolates with MIC > 0.5 g/mL had no mutations that could be related to other mechanisms of resistance.
As presented in the study, the high prevalence of clarithromycin-resistant due to point mutations of the 23S rRNA gene indicates the necessity of revising the standard treatment regimen based on antibiotic susceptibility pattern of each region.
是一种常见的感染性细菌，主要存在于胃十二指肠疾病中。克拉霉素耐药菌株的增加是成功治疗该菌感染的主要挑战。本研究旨在检测从胃活检中分离的 菌株的克拉霉素耐药模式，并评估 23S rRNA 基因的点突变。 在本描述性横断面研究中，我们招募了 2018 年 4 月至 7 月期间来自伊朗伊斯法罕沙里亚特医院内镜中心的 165 名胃肠道疾病患者。通过培养诊断 感染，采用 E 试验评估分离株对克拉霉素的敏感性。根据 EUCAST 建议获得最小抑菌浓度（MIC）值。还使用荧光原位杂交（FISH）来确定与克拉霉素耐药相关的点突变。
通过培养，从 50.3%（83/165）的胃活检标本中分离出 。E 试验显示，克拉霉素耐药的总频率为 25.3%（21/83）。在耐药基因型分析中，有 19 个分离株发生突变。A2143G 和 A2144G 突变的发生率分别为 68.4%（13/19）和 31.5%（6/19）。没有一个分离株存在 A2143C 突变。2 株 MIC > 0.5μg/ml 的分离株没有突变，可能与其他耐药机制有关。
正如研究所示，由于 23S rRNA 基因的点突变导致克拉霉素耐药的 发生率较高，表明有必要根据每个地区的抗生素药敏模式修订标准治疗方案。
