Deguchi K, Yokota N, Koguchi M, Suzuki Y, Suzuki K, Fukayama S, Ishihara R
Section of Studies, Tokyo Clinical Research Center.
Jpn J Antibiot. 1993 Feb;46(2):115-22.
We assessed the bacteriological efficacies of cefotiam (CTM) plus imipenem (IPM) and CTM plus vancomycin (VCM) therapies against methicillin-resistant Staphylococcus aureus (MRSA) in an in vitro system. The results are summarized as follows. 1. It appeared that the bacteriological efficacies of CTM+IPM therapy against MRSA strains were different against different target MRSA strains. In other words, the FIC indices of CTM+IPM were distributed in a wide range of < or = 0.5- > 2.0. The strains showing MIC levels of < or = 8 micrograms/ml in IPM concentrations showed a strong correlation with FIC index values of < or = 0.5, and the strains showing the MIC level of > or = 128 micrograms/ml in IPM concentration showed a strong correlation with FIC index values of > 2.0. Hence, the strains showing FIC indices < or = 0.5 were considered to be newborn strains with penicillin-binding protein 2' (PBP-2'), those showing FIC indices > 0.5- < or = 2.0 were considered to be strains with increasing production in PBP-2', and those showing FIC indices > 2.0 were considered to be strains with increasing productions in both PBP-2' and PBP-m2. In strains with FIC indices higher than 2.0, the 2 drugs may possibly share the action mechanism and the activity center thus they compete with each other.(ABSTRACT TRUNCATED AT 250 WORDS)
我们在体外系统中评估了头孢替安（CTM）联合亚胺培南（IPM）以及CTM联合万古霉素（VCM）治疗耐甲氧西林金黄色葡萄球菌（MRSA）的细菌学疗效。结果总结如下。1. CTM + IPM治疗对MRSA菌株的细菌学疗效因不同的目标MRSA菌株而异。换句话说，CTM + IPM的FIC指数分布在广泛的范围，即≤0.5至＞2.0。IPM浓度下最低抑菌浓度（MIC）水平≤8微克/毫升的菌株与FIC指数值≤0.5有很强的相关性，而IPM浓度下MIC水平≥128微克/毫升的菌株与FIC指数值＞2.0有很强的相关性。因此，FIC指数≤0.5的菌株被认为是具有青霉素结合蛋白2'（PBP - 2'）的新生菌株；FIC指数＞0.5至≤2.0的菌株被认为是PBP - 2'产量增加的菌株；FIC指数＞2.0的菌株被认为是PBP - 2'和PBP - m2产量均增加的菌株。在FIC指数高于2.0的菌株中，这两种药物可能共享作用机制和活性中心，因此它们相互竞争。（摘要截短于250字）
