This study aimed at investigating the in vitro effectiveness of aztreonam/avibactam, colistin/avibactam, colistin/apramycin, and meropenem/apramycin combinations against carbapenemase-producing, extensively drug-resistant (XDR) Klebsiella pneumoniae strains. This study evaluated 38 carbapenem-resistant, carbapenemase-producing, and XDR K. pneumoniae strains. The checkerboard method was used to examine the efficacy of aztreonam/avibactam, and meropenem/apramycin combinations in all strains and the colistin/apramycin combination in colistin-resistant strains (n = 26). It was found that when used alone, aztreonam and avibactam had high minimum inhibitory concentration values in all strains and that all strains were resistant to aztreonam. Nevertheless, the aztreonam/avibactam combination was found to have a synergistic effect against all strains. Apramycin alone was effective against 30 K. pneumoniae strains (79%); however, 8 strains (21%) were found to be resistant. In the synergy testing of 26 colistin-resistant strains with the checkerboard method, the colistin/apramycin combination was found to have a synergistic effect against 4 strains (15.3%), an antagonistic effect against 8 strains (30.7%), and an additive effect against 14 strains (54%). By comparison, the meropenem/apramycin combination had a synergistic effect against 20 strains (52%) and an additive effect against 12 strains (31%). The aztreonam/avibactam combination showed a high in vitro synergistic effect on carbapenemase-producing and XDR K. pneumoniae strains, such as Metallo-β-lactamase, and provided good prospects for the successful treatment. The meropenem/apramycin combination was also highly synergistic. The synergistic effects were low for the colistin/apramycin combination that was tested on colistin-resistant strains. However, it is promising that apramycin has low minimal inhibitory concentration values.

中文翻译：

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氨曲南/阿维巴坦，阿霉素，阿霉素和美罗培南/阿霉素联合用药对产生碳青霉烯酶，广泛耐药的肺炎克雷伯菌的体外作用研究。

这项研究旨在调查氨曲南/ avibactam，costin / avibactam，costin / apramycin和meropenem / apramycin组合对产生碳青霉烯酶，广泛耐药（XDR）的肺炎克雷伯菌肺炎菌株的体外有效性。这项研究评估了38株耐碳青霉烯，产生碳青霉烯酶和XDR肺炎克雷伯菌的菌株。棋盘格方法用于检查氨曲南/ avibactam和美罗培南/ apramycin组合在所有菌株中的功效，以及大肠杆菌素/ apramycin组合在对大肠杆菌素耐药的菌株中的功效（n = 26）。发现单独使用氨曲南和阿维巴坦在所有菌株中均具有较高的最小抑菌浓度值，并且所有菌株均对氨曲南具有抗性。然而，发现氨曲南/阿维巴坦组合对所有菌株具有协同作用。单独的安普霉素可有效抵抗30 K.肺炎毒株（79％）; 但是，发现有8株（21％）具有抗药性。在用棋盘法对26个大肠菌素耐药菌株进行协同测试中，发现大肠菌素/ apramycin组合对4个菌株（15.3％）具有协同作用，对8个菌株（30.7％）具有拮抗作用，并且具有累加作用。对抗14株（54％）。相比之下，美罗培南/ apramycin组合对20个菌株（52％）具有协同作用，对12个菌株（31％）具有累加作用。氨曲南/ avibactam组合对产生碳青霉烯酶和XDR肺炎克雷伯菌具有很高的体外协同作用菌株，如Metallo-β-内酰胺酶，为成功治疗提供了良好的前景。美罗培南/ apramycin的组合也是高度协同的。在大肠菌素抗性菌株上测试的大肠菌素/ apramycin组合的协同效应很低。但是，有希望的是阿普霉素的最低抑菌浓度值低。