Recent outbreaks of cardiac surgery-associated Mycobacterium chimaera infections have highlighted the importance of species differentiation within the Mycobacterium avium complex and pointed to a lack of antibiotic susceptibility data for M. chimaera. Using the MGIT 960/EpiCenter TB eXiST platform, we have determined antibiotic susceptibility patterns of 48 clinical M. chimaera isolates and 139 other nontuberculous mycobacteria, including 119 members of the M. avium complex and 20 Mycobacterium kansasii isolates toward clofazimine and other drugs used to treat infections with slow-growing nontuberculous mycobacteria (NTM). MIC₅₀, MIC₉₀, and tentative epidemiological cutoff (ECOFF) values for clofazimine were 0.5 mg/liter, 1 mg/liter, and 2 mg/liter, respectively, for M. chimaera. Comparable values were observed for other M. avium complex members, whereas lower MIC₅₀ (≤0.25 mg/liter), MIC₉₀ (0.5 mg/liter), and ECOFF (1 mg/liter) values were found for M. kansasii. Susceptibility to clarithromycin, ethambutol, rifampin, rifabutin, amikacin, moxifloxacin, and linezolid was in general similar for M. chimaera and other members of the M. avium complex, but increased for M. kansasii. The herein determined MIC distributions, MIC₉₀, and ECOFF values of clofazimine for M. chimaera and other NTM provide the basis for the definition of clinical breakpoints. Further studies are needed to establish correlation of in vitro susceptibility and clinical outcome.

中文翻译：

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嵌合分枝杆菌和其他非结核分枝杆菌的药敏分布

最近爆​​发的与心脏手术相关的嵌合体分枝杆菌感染凸显了鸟分枝杆菌复合体内物种分化的重要性，并指出缺乏嵌合体分枝杆菌的抗生素敏感性数据。使用 MGIT 960/EpiCenter TB eXiST 平台，我们确定了 48 种临床分枝杆菌和 139 种其他非结核分枝杆菌的抗生素敏感性模式，包括 119 种鸟分枝杆菌复合体成员和 20 种堪萨斯分枝杆菌分离株对氯法齐明和其他药物的敏感性模式治疗缓慢生长的非结核分枝杆菌 (NTM) 感染。麦克风₅₀ , 麦克风₉₀和暂定流行病学截止值 (ECOFF) 氯法齐明分别为 0.5 毫克/升、1 毫克/升和 2 毫克/升，分别为M. chimaera。观察到其他鸟分枝杆菌复合体成员的可比值，而M. kansasii的 MIC ₅₀（≤0.25 毫克/升）、MIC ₉₀（0.5 毫克/升）和 ECOFF（1 毫克/升）值较低。对克拉霉素、乙胺丁醇、利福平、利福布汀、阿米卡星、莫西沙星和利奈唑胺的敏感性在大体上与嵌合分枝杆菌和鸟分枝杆菌复合体的其他成员相似，但对堪萨斯分枝杆菌增加。此处确定的 MIC 分布，MIC ₉₀和氯法齐明对嵌合体分枝杆菌和其他 NTM 的 ECOFF 值为临床断点的定义提供了基础。需要进一步的研究来确定体外易感性和临床结果的相关性。