Antimicrobial Activities of Arbekacin against Recent Isolates of Staphylococcus aureus in Korean Hospitals / 대한임상미생물학회지

ABSTRACT

BACKGROUND: As clinical isolates of Staphylococcus aureus with reduced inhibition zone of arbekacin in disk diffusion susceptibility tests are observed frequently, we examined their susceptibility to the antibiotic by comparing the results of the agar dilution testing with those of disk diffusion testing. METHODS: During the period of May through July, 2004, 88 isolates of methicillin-resistant and 11 methicillin-susceptible S. aureus were collected from clinical specimens in Pusan National University Hospital and Kosin University Gospel Hospital. Minimal inhibitory concentrations (MICs) of arbekacin were determined by the agar dilution method, and inhibition zones by the disk diffusion method. RESULTS: All of the 99 isolates were tested susceptible to arbekacin by the agar dilution method (MIC < or = 8 mg/L). By the disk diffusion method, however, 5 isolates (5.1%) were intermediate (minor error) and 2 isolates (2.0%) resistant (major error). CONCLUSION: All isolates were susceptible to arbekacin, but the disk diffusion method showed 7 per cent of minor or major errors.