In-vitro antimicrobial activity of linezolid and tigecycline against colonized vancomycin-resistant enterococci

Enterococci, in spite of the fact that their virulance are low, important nosocomial causative agents. Because of the facts that they are able to grow and survive under hard conditions and they have intrinsic resistance to many antimicrobial agents and able to acquire new mechanisms of resistance, they are one of the most freuquent isolated microorganisms from hospital infection in recently.Our study was performed between 01.09.2007 and 01.09.2009. The aim of this study is to determine in-vitro susceptibility of tigecycline which alternatives that may be in vancomycin-resistant enterococci (VRE) infections and linezolid which is being used since the year 2005 in Turkey.In this study in-vitro susceptibility of tigecycline and linezolid from isolated VRE strains and VRE colonization was investigated in the patients hospitalized in Fırat University Hospital Anesthesiology and Reanimation Clinic and Oncology Clinic for 2-year period. From 680 patients VRE positivity was determined in 105 patients. Of the strains isolated as VRE, 80 (%76.2) were identified as E. faecium and 25 (%23.8) as E. faecalis. Antibiotic use was present in 105 patients. Mostly used antibiotics were glycopeptide antibiotics and broad-spectrum cephalosporins. According to linezolid and tigecycline MIC values which were determined by broth microdilution, resistance to this antibiotics was not detected in colonized VRE strains.As a result, enterococci are important nosocomial pathogens in the clinics where the patients have long-term treatment and the widespread antibiotic use. For this reason the antibiotic susceptibility of enterococci, isolated species determination and vancomycin susceptibility should be investigated. For the patients in whom VRE has been detected, infection control and prevention must be done.Keywords: Vancomycine resistant enterococcus, linezolid, tigecycline