Khodabux Rhea Michelle J, Mariappan Shanthi, Sekar Uma
Department of Microbiology, Sri Ramachandra Institute of Higher Education and Research (SRIHER), Porur, Chennai, Tamil Nadu, India.
J Lab Physicians. 2022 Oct 20;15(2):207-211. doi: 10.1055/s-0042-1757419. eCollection 2023 Jun.
has emerged as an important multidrug-resistant nosocomial pathogen. Linezolid is useful in the treatment of severe infections caused by methicillin-resistant . Resistance to linezolid in is due to one or more of the following mechanisms: acquisition of the (chloramphenicol florfenicol resistance) gene, mutation in the central loop of domain V of the 23S rRNA, and mutation in the and genes. This study was carried out to detect and characterize resistance to linezolid among the clinical isolates of . The study included 84 clinical isolates of . Susceptibility to various antibiotics was determined by disc diffusion method. Minimum inhibitory concentration (MIC) was determined by agar dilution method for linezolid. Methicillin resistance was screened using oxacillin and cefoxitin disc. Polymerase chain reaction was done to detect and mutations in the V domain of the 23S rRNA gene. Resistance to linezolid was exhibited by 3 of the 84 study isolates with MIC more than 128 µg/mL. The gene was detected in all the three isolates. The G2603T mutation was observed in the domain V of the 23S rRNA among two isolates, whereas one isolate lacked any mutation. The emergence and spread of linezolid-resistant isolates carrying G2603T mutation in the domain V of the 23S rRNA and harboring the gene pose a threat in clinical practice.
已成为一种重要的多重耐药医院病原体。利奈唑胺可用于治疗由耐甲氧西林的……引起的严重感染。……对利奈唑胺的耐药性归因于以下一种或多种机制：获得……（氯霉素氟苯尼考耐药性）基因、23S rRNA结构域V中心环的突变以及……和……基因的突变。本研究旨在检测和表征……临床分离株对利奈唑胺的耐药性。
该研究包括84株……临床分离株。通过纸片扩散法测定对各种抗生素的敏感性。采用琼脂稀释法测定利奈唑胺的最低抑菌浓度（MIC）。使用苯唑西林和头孢西丁纸片筛选耐甲氧西林情况。进行聚合酶链反应以检测23S rRNA基因V结构域中的……和突变。
84株研究分离株中有3株对利奈唑胺耐药，MIC大于128 µg/mL。在所有三株分离株中均检测到……基因。在两株分离株的23S rRNA结构域V中观察到G2603T突变，而一株分离株未发现任何突变。
携带23S rRNA结构域V中G2603T突变且含有……基因的耐利奈唑胺……分离株的出现和传播在临床实践中构成威胁。
