Vancomycin 내성 장구균의 분포 및 Vancomycin, penicillin 및 Gentamicin의 병용 효과

Abstract

Infections caused by vancomycin-resistant enterococci (VRE) are becoming increasingly prevalent throughout the world. Because of the resistance of vancomycin resistance is troublesome. The optimum drug regimen for treatment of infections due to VRE is not known. Very few data have been published concerning in VRE-infected patients. The combimed regimen may offer a treatment for patients infected with VRE. The purpose of this study was to examine the incidence of VRE among total enterococci form clinical specimen and investigate the antimicrobial synergistic killing of clinical isolates of VRE belonging to gentoypic resistance classes vanA, vanB, and vanC. A total or 1,286 enterococcal isolates from patients over a period of 12 months were screened for vancomycin resistance using brain heart infusion agar plates supplemented with 6㎍/mL of vancomycin. The incidence of VRE among enterococcal isolates was calculated form microbiology statistics program. Nine strains of VRE and 2 strains of vancomycin-susceptible enterococci were utilized in this study. Minimal inhibitory concentrations (MIC) weredetermined by agar dilution method. Synergistuc inhibition of growth was assessed by assition vancimycin, penicillin, gentamicin, or combinations of these antibiotics to cultures in the early logarithmic phase of growth. Synergy was defined as a decrease in CFU/mL by at least 2 log10 after 24h compared with the effect of the most active single agent. In the 12 months, the incidence of VRE was 3.2%. Among 9 strains, analyses, the frequency of vanB, vanC1, and vanC2 types was, 2, 4, and 3 steains, respectively. Vancom-ycin-penicillin-gentamicin, and vancomucin-penicillin resulted in 2 or more logs of killing above that the most effetive single agent for all vanA and vanB strains. All vanC strains were resistant to any antibiotics combination. Continued vigilanve, strict enforcement of infection control, and curtailment of vancomycin use seen to be our best approaches to controlling this increasungly important problem. For this purposes, accurate and timely detection of vancomycin resistance and periodic investigation for incidence is essential. Triple combination therapy and vancomycin plus penicillin reginen may be effective for the treatment of infections caused by vancomyiin-resistant enterococci belonging to genotypic classes vanA and vanB. Further sutdies are needed for the new therapeutic regimen against vanC strains.