Mascellino M T, Iona E, Fattorini L, De Gregoris P, Hu C Q, Santoro C, Orefici G
Institute of Infectious Disease, University La Sapienza, Rome, Italy.
J Chemother. 1991 Dec;3(6):357-62. doi: 10.1080/1120009x.1991.11739120.
The activity of clarithromycin and five other antimicrobial agents, namely amikacin, rifampicin, rifabutin, clofazimine and ciprofloxacin, was assessed both by an agar dilution and a radiometric method in broth on 11 Mycobacterium avium-intracellulare complex (MAC) strains, recently isolated from AIDS patients. Minimum inhibitory concentrations (MICs) radiometrically determined were, in general, several times lower than MICs assessed in agar, probably because of a partial degradation of antimicrobials during the long incubation period needed for tests in solid medium. When tested in broth, rifabutin and clofazimine showed very low MICs 90 (0.24 and 0.78 microgram/ml, respectively). Ciprofloxacin and clarithromycin also had MICs90 in the range of peak serum levels (1.93 and 3.76 micrograms/ml, respectively). Moreover, all these antimicrobials are known to concentrate several times in macrophages. MICs90 were higher for amikacin (11 micrograms/ml) and for rifampicin (8 micrograms/ml). When clarithromycin was tested against three MAC strains in combination with another drug, it showed a synergistic effect only when combined with rifampicin. Some synergistic effect was observed also when combining clarithromycin with rifampicin and amikacin, whereas in combination with rifabutin and clofazimine there was only an additive effect.
采用琼脂稀释法和液体培养基中的放射测定法，对从艾滋病患者中最近分离出的11株鸟分枝杆菌 - 胞内分枝杆菌复合菌（MAC）菌株，评估了克拉霉素及其他五种抗菌剂（即阿米卡星、利福平、利福布汀、氯法齐明和环丙沙星）的活性。通过放射测定法测定的最低抑菌浓度（MIC）通常比琼脂法测定的MIC低几倍，这可能是由于在固体培养基中进行测试所需的长时间孵育期间抗菌剂发生了部分降解。在液体培养基中进行测试时，利福布汀和氯法齐明的MIC90非常低（分别为0.24和0.78微克/毫升）。环丙沙星和克拉霉素的MIC90也处于血清峰值水平范围内（分别为1.93和3.76微克/毫升）。此外，已知所有这些抗菌剂在巨噬细胞中会浓缩几倍。阿米卡星（11微克/毫升）和利福平（8微克/毫升）的MIC90较高。当克拉霉素与另一种药物联合针对三株MAC菌株进行测试时，仅与利福平联合时显示出协同作用。克拉霉素与利福平和阿米卡星联合时也观察到了一些协同作用，而与利福布汀和氯法齐明联合时仅存在相加作用。
