Mataracı-Kara Emel, Damar-Çelik Damla, Özbek-Çelik Berna
Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Istanbul University, 34116, Beyazit-Istanbul, Turkey.
Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Marmara University, Başıbüyük-Istanbul, Turkey.
Eur J Clin Microbiol Infect Dis. 2025 Mar;44(3):587-596. doi: 10.1007/s10096-024-05017-0. Epub 2024 Dec 20.
Achromobacter spp. may form biofilm in patients' respiratory tracts and cause serious infections. This research examined the bactericidal and synergistic effects of ceftazidime/avibactam (CZA) alone and in combination with different antibiotics against Achromobacter spp.
MICs of 52 Achromobacter spp. were determined by broth microdilution. In-vitro time-kill curve experiments assessed CZA's bactericidal and synergistic properties alone and in combination with other antibiotics. Moreover, the antibiofilm activity of CZA alone or in combination with the antibiotics was assessed with using microplate method.
Based on MIC values, CZA exhibited four times greater in-vitro activity against tested strains than ceftazidime. The most effective agent was meropenem, with a 92% susceptibility level on the tested strains. On the other hand, ciprofloxacin was found to be bactericidal at both 1 × and 4xMIC concentrations. CZA, chloramphenicol and meropenem were observed to have bactericidal effects alone at 4xMIC concentrations against the tested isolates. CZA + CS and CZA + MEM showed synergy in three out of five and two out of five strains tested at 1xMIC, respectively. Furthermore, the pairing of CZA with colistin, CZA with meropenem and CZA with ciprofloxacin exhibited a synergistic impact at 4xMIC. Moreover, combination therapy CZA with the tested antibiotics showed reduced biofilm formation in a concentration-dependent manner at 24 h.
The outcomes of this research also suggest that CZA plus colistin, meropenem, or ciprofloxacin were more productive against Achromobacter strains. To our knowledge, this is the first article to evaluate the synergistic and antibiofilm activities of CZA alone or in combination with different agents against Achromobacter species.
无色杆菌属可能在患者呼吸道形成生物膜并导致严重感染。本研究检测了头孢他啶/阿维巴坦（CZA）单独及与不同抗生素联合对无色杆菌属的杀菌及协同作用。
采用肉汤微量稀释法测定52株无色杆菌属的最低抑菌浓度（MIC）。体外时间杀菌曲线实验评估CZA单独及与其他抗生素联合的杀菌及协同特性。此外，采用微孔板法评估CZA单独或与抗生素联合的抗生物膜活性。
基于MIC值，CZA对受试菌株的体外活性比头孢他啶高4倍。最有效的药物是美罗培南，受试菌株的敏感率为92%。另一方面，发现环丙沙星在1×和4×MIC浓度下均具有杀菌作用。观察到CZA、氯霉素和美罗培南在4×MIC浓度下对受试分离株单独具有杀菌作用。CZA + CS和CZA + MEM在1×MIC测试的五株菌株中分别有三株和两株显示协同作用。此外，CZA与黏菌素、CZA与美罗培南以及CZA与环丙沙星的组合在4×MIC时表现出协同作用。此外，CZA与受试抗生素的联合治疗在24小时时以浓度依赖方式减少生物膜形成。
本研究结果还表明，CZA加黏菌素、美罗培南或环丙沙星对无色杆菌菌株更有效。据我们所知，这是第一篇评估CZA单独或与不同药物联合对无色杆菌属的协同和抗生物膜活性的文章。
