Department of Pathobiology, School of Public Health and Biotechnology Research Center, Tehran University of Medical Sciences, Tehran, Iran.
Department of Internal Medicine, Shahid Mostafa Khomeini Hospital, Shahed University, Tehran, Iran.
Microb Drug Resist. 2020 Mar;26(3):245-250. doi: 10.1089/mdr.2019.0223. Epub 2019 Sep 23.
Increasing macrolide resistance of strains is becoming a public health concern worldwide. Nevertheless, no comprehensive genomic background of circulating isolates is available in our region. We aimed to study the genetic diversity of this microorganism using the multiple-locus variable-number tandem-repeat analysis method and to investigate the relationships between MLVA types and macrolide susceptibility profiles of the isolates. A total of 270 patients attending Tehran general university hospitals were included in this study. One throat swab was taken from each patient. was identified using culture and PCR assay. Macrolide resistance was determined using the broth microdilution method. The MLVA was performed by amplification of four variable-number tandem-repeat loci. Of 270 specimens, was detected in 25.2% ( = 68) and 21.8% ( = 59) samples using PCR and culture, respectively. Approximately 56.9% of isolates were resistant to macrolides. Fifty-one of 59 isolates were divided into 6 distinct MLVA types. The macrolide-resistant (MRMP) rate in this study was relatively high and most of the MRMP isolates were assigned into the type 4/5/7/2. Since a significant association between MLVA type 4/5/7/2 and macrolide resistance of isolates was observed, further monitoring of genetic diversity of MRMP isolates might facilitate better understanding of epidemiology of this microorganism. Besides surveillance of the antibiotic susceptibility might be helpful to make necessary reconsiderations on guidelines for treatment of infection.
菌株中大环内酯类耐药性的增加正成为全球关注的公共卫生问题。然而，我们所在地区尚未获得有关循环分离株的全面基因组背景信息。我们旨在使用多位点可变数目串联重复分析方法研究该微生物的遗传多样性，并研究分离株的 MLVA 类型与大环内酯类药物敏感性之间的关系。
本研究纳入了 270 名前往德黑兰综合大学附属医院就诊的患者。从每位患者中采集一个咽拭子。通过培养和 PCR 检测鉴定为 。采用肉汤微量稀释法测定大环内酯类药物耐药性。通过扩增四个可变数目串联重复位点进行 MLVA。
在 270 个标本中，PCR 和培养分别检测到 25.2%（=68）和 21.8%（=59）的标本中存在 。约 56.9%的分离株对大环内酯类药物耐药。59 株分离株中有 51 株分为 6 种不同的 MLVA 型。
本研究中，耐大环内酯类肺炎链球菌（MRMP）的比率相对较高，大多数 MRMP 分离株被分为 4/5/7/2 型。由于观察到 MLVA 型 4/5/7/2 与 分离株对大环内酯类药物的耐药性之间存在显著相关性，因此进一步监测 MRMP 分离株的遗传多样性可能有助于更好地了解该微生物的流行病学。此外，监测抗生素敏感性可能有助于对治疗 感染的指南进行必要的重新考虑。
