건강인의 비인강에서 Staphylococcus aureus분리와 Methicillin 내성 Staphylococcus aureus의 항균제 감수성

Abstract

Methicillin - resistant Staphylococcus aureus (MRSA) has been well recognized as a cause agent of nosocomial infection. In this study, 128 strain of S. aureus from healthy students of Wonkwang Health Junior College, which were is이ated during the period from 1994 to 1996, were tested for the investigation of their drug resistance. The method of MRSA detection, methicillin susceptibility by the agar screening, Vitek MIC test and disc diffusion tests were compared. This studies showed the f ollowing : First, 128 (14.8%) strains of S. aureus were isolated from 867 persons, while those were 25 (12.8%) strains in male and 103 (15.4%) strains in female. No differences were noted in the prevalence rate by years and four strains(0.5%) of MRSA were isolated from healthy per sons. Second, MRSA detection by the agar screening test and by the disk dif f usion test were 100% and 96.2% in agreement with agar Vitek MIC test. Third, among the MSSA isolates, resistant to gentamicin and erythromycin were 27% and 7% respectively, while all of the cephalothin, ciprofloxacin, imipenem, teicoplanin and vancomycin were susceptible. However, to ciprofloxacin, 89% of the MRSA was resistant while all were resistant to cephalothin, erythromycin, gentamicin and imipenem , but all of those were susceptible to teicoplanin and vancomycin. The ranges of minium inhibitory concentrations(MIC) of teicoplanin were 0.25~16㎍/ml, MIC50 4㎍/ml and MIC90 16㎍/ml against MRSA, while MIC range of vancomycin were 2~4 명㎍/ml, MIC50 2㎍/ml and MIC90 4 ㎍/ml, and more than 64㎍/ml to other antimicrobial agents. It is concluded that healthy individuals sometimes carry MRSA in their nares, and agar screening test is more accurate than standard disk diffusion method for the detection of MRSA, and teicoplanin and vancomycin could be a useful antibiotic for the treatment of serious infections due to MRSA and MSSA.