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 Mar;46(3):234-41.
Against 200 strains of methicillin-resistant Staphylococcus aureus (MRSA) isolated from 1990 to 1991, minimum inhibitory concentrations (MICs) of a total of 15 antibacterial agents including arbekacin (ABK) were determined. In addition coagulase types of the tested strains were determined and classified according on their origins. 1. Among the coagulase types of 200 strains, type II were 63.5%, type IV 18.5%, type VII 11.0% and the other types 7.0%. Type II strains were prevailing among those isolated from the respiratory tract specimens and type IV among those from the surgical specimens. These results were in agreement with other recent reports including our previous ones. 2. The MIC50 of methicillin, 6 cephalosporins (CEPs), imipenem, fosfomycin (FOM), gentamicin, tobramycin and clindamycin for 200 strains ranged from 50 to > 100 micrograms/ml. On the other hand, MIC50 and MIC90 of ABK, minocycline (MINO) and vancomycin (VCM) were 0.78 and 3.13 micrograms/ml for ABK, 0.39 and 50 micrograms/ml for MINO, and 0.78 and 1.56 micrograms/ml for VCM. 3. The MIC90 of ABK against coagulase type IV strains was rather high, 12.5 micrograms/ml. However, the strains inhibited by 6.25 to 12.5 micrograms/ml of ABK were isolated even in our studies performed in 1986, 1988 and 1989. Further studies are therefore required to confirm whether appearance of these strains used in the present study inhibited at relatively high concentrations of ABK is due to the use of ABK. 4. It is reported that, at present, most of the MRSAs spreading in Japan are acceleratedly acquiring resistance to many drugs, and especially, they are developing high resistance against beta-lactams. ABK showed potent antibacterial activities even against these strains. Since ABK has been shown to display potent activities against MRSA in combination with beta-lactams or FOM, we believe ABK is one of the useful aminoglycoside antibiotics for the treatment of MRSA infections.
针对1990年至1991年分离出的200株耐甲氧西林金黄色葡萄球菌（MRSA），测定了包括阿贝卡星（ABK）在内的总共15种抗菌药物的最低抑菌浓度（MIC）。此外，还测定了受试菌株的凝固酶类型，并根据其来源进行了分类。1. 在200株菌株的凝固酶类型中，II型占63.5%，IV型占18.5%，VII型占11.0%，其他类型占7.0%。II型菌株在呼吸道标本分离株中占主导地位，IV型在手术标本分离株中占主导地位。这些结果与包括我们之前报告在内的其他近期报告一致。2. 甲氧西林、6种头孢菌素（CEP）、亚胺培南、磷霉素（FOM）、庆大霉素、妥布霉素和克林霉素对200株菌株的MIC50范围为50至>100微克/毫升。另一方面，ABK、米诺环素（MINO）和万古霉素（VCM）的MIC50和MIC90分别为：ABK为0.78和3.13微克/毫升，MINO为0.39和50微克/毫升，VCM为0.78和1.56微克/毫升。3. ABK对凝固酶IV型菌株的MIC90相当高，为12.5微克/毫升。然而，即使在我们1986年、1988年和1989年进行的研究中，也分离出了被6.25至12.5微克/毫升ABK抑制的菌株。因此，需要进一步研究来确认本研究中使用的这些在相对高浓度ABK下被抑制的菌株的出现是否归因于ABK的使用。4. 据报道，目前在日本传播的大多数MRSA正在加速获得对多种药物的耐药性，尤其是对β-内酰胺类药物产生高度耐药性。ABK即使对这些菌株也显示出强大的抗菌活性。由于ABK已被证明与β-内酰胺类药物或FOM联合使用时对MRSA具有强大活性，我们认为ABK是治疗MRSA感染有用的氨基糖苷类抗生素之一。
