In vitro-activity of tigecycline and daptomycin against vancomycin-resistant enterococci and meticillin-resistant staphylococci

Abstract number: P1719

Tsiringa A., Skandami-Epitropaki B., Xanthaki A., Arida P., Marounga E., Toutouza M.

Objective: Tigecycline, a glycylcycline and daptomycin, a lipopeptide are novel antibacterial compounds undergoing clinical development. The aim of this study was to assess the in vitro-activity of Tigecycline and Daptomycin against VRE and Meticillin-resistant Staphylococci from patients with positive cultures in our hospital.

Methods: A total of 32 clinical isolates of VRE (28 E. faecium and 4 E. faecalis) and 30 Staphylococci (20 MRSA and 10 MRSE) were isolated from various clinical specimens in one year. Identification was determined with the use of VITEK-II system (BIOMERIEUX-France). The antimicrobial susceptibility was determined by Kirby-Bauer, CLSI guidelines. Phenotypically all isolates of Enterococci were VanA type (MIC Vancomycin >256 mg/ml,MIC Teicoplanin >16 mg/ml). They were also susceptible to linezolid, except one, and expressed various susceptibility patterns to other antibiotics. All isolates of Staphylococci were susceptible to Vancomycin, Teicoplanin Linezolid and expressed various susceptibility patterns to other antibiotics. MICs were determined by E-test method (AB Biodisk). The susceptible breakpoints, according to CLSI guidelines were:.MIC Tigecyclineleqslant R: less-than-or-eq, slant0.25 mg/l, MIC Daptomycin leqslant R: less-than-or-eq, slant4 mg/l for enterococci and MIC Tigecycline leqslant R: less-than-or-eq, slant0.5 mg/l, MIC Daptomycin <1 mg/l for Staphylococci.

Results: The isolates of enterococci and staphylococci were all susceptible to tigecycline. All the isolates of enterococci were susceptible to daptomycin, except one. All the MRSA and all the MRSE, except one, were susceptible to daptomycin.

Tigecycline MIC values:

For VRE faecium (28): 42.9% at 0.064 mg/l and 57.1% at 0.094 mg/l

For VRE faecalis (4): 75% at 0.064%mg/l and 25% at 0.094% mg/l

For MRSA(20): 20% at 0.19 mg/l, 40% at 0.25 mg/l, 35% at 0.38 mg/l and 5% at 0.5 mg/l

For MRSE (10): 20% at 0.064 mg/l, 20% at 0.094 mg/l, 10% at 0.19 mg/l, 20% at 0.25 mg/l, 10% at 0.38 mg/l and 20% at 0.5 mg/l.

Daptomycin MIC values:

For VRE faecium (28): 39.4% at 2 mg/l, 35.7% at 3 mg/l, 21.5% at 4 mg/l and 3.4% at 8 mg/l.

For VRE faecalis (40): 25% at 1 mg/l, 25% at1.5 mg/l, 25% at 2 mg/l and 25% at3 mg/l.

For MRSA (20): 5% at 0.38 mg/l, 10% at 0.5 mg/l, 45% at 0.75 mg/l and 40% at1 mg/l.

For MRSE (10): 11.2% at 0.38 mg/l, 22.2% at 0.75 mg/l and 66.6% at 1 mg/l.

Conclusion: These results suggest that both tigecycline and daptomycin may play important roles in the treatment of infections caused by VRE and meticillin-resistant staphylococci including drug-resistant strains.

Session Details

Date: 19/04/2008
Time: 00:00-00:00
Session name: 18th European Congress of Clinical Microbiology and Infectious Diseases
Location: Barcelona, Spain
Presentation type:
Back to top