Tigecycline Comparison with Minocycline Resistance Pathogens. A Worldwide Perspective

Objectives: Tigecycline, a new glycylcycline is an analogue of tetracycline that demonstrates activity against bacterial strains carrying tetracycline (minocycline) resistance mechanisms. This report documents the activity of TIG against minocycline resistant isolates collected worldwide, 2004–2007, as part of the Tigecycline Evaluation Surveillance Trial (TEST) study. Methods: Between 2004 and 2007, 387 hospital sites in 48 countries collected significant pathogens associated with 8 specimen types, were identified to species level and MICs performed for each strain to a supplied panel of antibiotics and interpreted according to CLSI guidelines. Results: The table below illustrates the activity of tigecycline to minocycline resistant pathogens. Conclusions: Tigecycline MIC90s were ≤0.5 mcg/ml for minocycline resistant gram-positive pathogens such as Enterococcus and S. aureus (including MRSA) and ≤8 mcg/ml for minocycline resistant gram-negative pathogens such as Enterobacteriaceae, including ESBL producers. Tigecycline demonstrated minimal activity against P. aeruginosa. Tigecycline demonstrates enhanced activity to many minocycline resistant pathogens.