ABSTRACT

Novel antimicrobial agents are necessary for the treatment of infections caused by gram positive pathogens, especially by Meticillin resistant Staphylococcus aureus (MRSA), because of the increas-ing worldwide resistance. Daptomycin; which has activity against a wide spectrum of gram posi-tive organisms, is a novel cyclic lipopeptide antimicrobial. It is indicated for the treatment of com-plicated skin and soft tissue infections, bacteremia and right side infective endocarditis caused by S. aureus. Beside once daily 4-6 mg/kg infusion dosing regimen it has a rapid bactericidal activity. MICs of daptomycin was compared with those of three antimicrobial agents (vancomycin, line-zolid, quinupristin-dalfopristin) which has a activity against gram positive bacteriae. MIC50 and MIC90 values of daptomycin, vancomycin, linezolid and quinupristin-dalfopristin were determined as 0.125mg/L-0.25mg/L, 1mg/L-1.5mg/L, 0.5mg/L-0.75mg/L and 0.5mg/L-0.75mg/L, respectively. With having the lowest MIC values, daptomycin may represent a therapeutic option for the infec-tions caused by gram positive pathogens.