Bayer A S, Chow A W, Concepcion N, Guze L B
Antimicrob Agents Chemother. 1978 Nov;14(5):720-2. doi: 10.1128/AAC.14.5.720.
The minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of 40 lactobacillus strains were determined against six antibiotics with broad anaerobic spectra. Penicillin, ampicillin, clindamycin, and cephalothin were the most active inhibitory agents, with 95 to 100% of the strains inhibited at clinically achievable serum levels. However, despite the inhibitory efficacy of these four agents, only 5 to 22% of the isolates were killed at achievable concentrations. MBC:MIC ratios were high, ranging from 30:1 for cephalothin to 266:1 for ampicillin. Cefoxitin and metronidazole were generally ineffective against lactobacilli, with 87.5 to 100% of strains having unachievable MICs and/or MBCs. These findings may partially explain the clinical observations noting the inability to eradicate endocarditic lactobacillemias despite readily achievable MICs.
测定了40株乳酸杆菌对六种具有广泛厌氧谱抗生素的最低抑菌浓度（MIC）和最低杀菌浓度（MBC）。青霉素、氨苄西林、克林霉素和头孢噻吩是最有效的抑菌剂，在临床可达到的血清水平下，95%至100%的菌株受到抑制。然而，尽管这四种药物具有抑制作用，但在可达到的浓度下，只有5%至22%的分离株被杀死。MBC:MIC比值很高，头孢噻吩为30:1，氨苄西林为266:1。头孢西丁和甲硝唑通常对乳酸杆菌无效，87.5%至100%的菌株其MIC和/或MBC无法达到。这些发现可能部分解释了临床观察结果，即尽管MIC很容易达到，但仍无法根除心内膜炎乳酸杆菌血症。
