鸟分枝杆菌复合群对16种抗感染药物药敏试验的分析

目的 通过比较3种新型喹诺酮类药物(西他沙星、加替沙星和莫西沙星)与其他13种抗感染药物对鸟分枝杆菌复合群(MAC)分离株的体外活性,初步探讨喹诺酮类药物用于治疗MAC疾病的可能性.方法 琼脂梯度稀释法测定上述16种抗感染药物对MAC分离株的最低抑菌浓度(MIC),比较其能抑制90%菌株生长的MIC(MIC90).结果 与胞内分枝杆菌相比,鸟分枝杆菌菌株的MIC范围分布更广,且MIC90多高于胞内分枝杆菌.4种大环内酯类药物中,克拉霉素对鸟分枝杆菌和胞内分枝杆菌的MIC90最低,分别为32和16 mg/L;4种利福霉素类化合物中利福拉齐对鸟分枝杆菌和胞内分枝杆菌的MIC90最低,分别为0.5和0.25 mg/L;5种喹诺酮类药物中西他沙星对鸟分枝杆菌和胞内分枝杆菌的MIC90最低,均为4 mg/L,加替沙星和莫西沙星均为8 mg/L.2株克拉霉素敏感株(MIC=0.5 mg/L)对其他抗感染药物均接近或达到MIC范围的下限,3株克拉霉素不敏感株(MIC=64 mg/L)对除喹诺酮类以外的抗感染药物均接近MIC范围的上限.结论 利福拉齐、西他沙星、加替沙星和莫西沙星对MAC分离株具有较强的体外活性.

Susceptibility test of the Mycobacterium avium complex to sixteen anti-infective agents

Objective To compare the in vitro activities of 13 anti-infective agents and 3 new quinolones (sitafloxacin, gatifloxacin and moxifloxacin ) against Mycobacterium avium complex (MAC)isolates ,and therefore to explore the possibility of using these quinolones to treat MAC diseases. Methods The minimal inhibitory concentration (MIC) of the above 16 anti-infective agents, including sitafloxacin,gatifloxacin and moxifloxacin against MAC isolates was determined by using agar dilution methods, and then the MIC90s of the different anti-infective agents were compared. Results The MICs of M. avium isolates showed a wider range and was less sensitive to most of the anti-infective agents as compared with M.intracellulare isolates. The MIC90s of clarithromycin against M. avium and M. intracellulare isolates were 32mg/L and 16 mg/L, respectively, which were the lowest among 4 macrolide compounds. The MIC90 of rifalazil were 0.5 mg/L and 0. 25 mg/L, respectively, which were the lowest among 4 rifamycin compounds.The MIC90 of sitafloxacin against M. avium and M. intracellulare isolates were both 4 mg/L, which were the lowest among 5 quinolones. For gatifloxacin and moxifloxacin, the MIC9o against M. avium and M.intracellulare isolates were both 8 mg/L Two clarithromycin-sensitive strains(MIC = 0.5 mg/L)showed a similar MIC of the lower limit for other compounds. Three clarithromycin-insensitive strains(MIC = 64 mg/L) showed a similar MIC of the upper limit for other compounds except quinolones. Conclusion Rifalazil,sitafloxacin, gatifloxacin and moxifloxacin showed acceptable in vitro activities against MAC isolates.