Methicillin 내성포도구균에 미치는 항균제 병용효과

Abstract

One hundred and thirty-one strains of staphylococci isolated from various clinical specimens in 1985 were tested for antimicrobial susceptibility to 16 drugs by microdilution broth method, and 24 strains were found to be resistant to methicillin (Mt). Mt-resistani staphylococci (MRS) were in most cases resistant to the other drugs tested except vancomycin (Vc) in high frequency, but most Mt-susceptible staphylococci were susceptible to the drugs cxccpt erythromycin (Em), tetracycline, gentamicin (Gm), and kanamycin (Km).

The combined activity of with the other drugs was tested on MRS by checkerboard and time-killing methods. Km showed marked synergistic activity with Alt with fractional inhibitory concentration (FIC) index of 0.05 to 0. o in 95% of strains. Vc, ampicillin, cephalothin, and penicillin also showed synergistic effects in more than 5(ol. strains. The combination of oxacillin also showed the synergistic activity with some other drugs, such as Em, rifampin, and trimethoprim. Gm was antagonistic with Mt in some strains, ；m(1 Km was antagonistic with Mt in most strains. Vc was synergistic with Mt, and moxalactam.